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Publication numberUS3715902 A
Publication typeGrant
Publication dateFeb 13, 1973
Filing dateFeb 10, 1971
Priority dateFeb 10, 1971
Also published asCA947016A1, DE2205734A1, DE2205734C2
Publication numberUS 3715902 A, US 3715902A, US-A-3715902, US3715902 A, US3715902A
InventorsFuchs Francis Joseph Jr
Original AssigneeWestern Electric Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method and apparatus for operating on a blank of material,e.g.,deep drawing
US 3715902 A
Images(6)
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Description  (OCR text may contain errors)

United States Patent 1191 Fuchs, Jr.

1451 Feb. 13, 1973 [54] METHOD AND APPARATUS FOR OPERATING ON A BLANK OF MATERIAL, E.G., DEEP DRAWING [75] Inventor: Francis Joseph Fuchs, Jr., Princeton Junction, NJ. [73] Assignee: Western Electric Co. The, New

York, NY.

:52 riled; -mi. mini [21] Appl.No.: 114,198

[52] US. Cl. ..72l60, 72/347, 29/421 3,349,153 10/1967 Beck 72/351 3,459,021 8/1969 Fuchs, Jr ..72/60 3,490,265 1/1970 Marcovitch ..72I348 FOREIGN PATENTS OR APPLICATIONS 625,011 6/1949 Great Britain ..72/349 Primary llg inerR ich ard J. Herbst Att0meyW. M. Ka im R. P. Mill e rand R: C. Winter [5 7] ABSTRACT Pressurized viscous fluid, pumped by annular pistons, flows in contact with one surface of a blank inwardly from ,the periphery thereof, thereby to force the opposite surface of the blank against a low friction surface, thereby to pressurize the blank and exert viscous drag force on the surface of the blank to extrude the peripheral portion of the blank inwardly, in cooperation with a ram perpendicularly engaging the central portion of the blank, to deep draw the blank through a die opening. In a modification, a heating element is provided in contact with the flow of viscous fluid opposite the surface of the blank contacted by the viscous fluid to raise the efficiency of the operation. In another modification, by proper staging, the average pressure in the viscous fluid can be made to increase in the overall direction of flow of the viscous fluid.

The viscous fluid can be applied to inwardly extrude the blank uniformly or non-uniformly. In yet another modification, pressurized viscous fluid, pumped by annular pistons, flows in contact with both faces of a blank inwardly from the periphery thereof, thereby to pressurize the blank and exert viscous drag force on both surfacesof the blank to extrude the peripheral portion of the blank inwardly.

192 Claims, 14 Drawing Figures PATENIED FEB 1 3 I975 SHEET 0F 6 iii g i M w; 3%

Jam? 3 P PATENTEDFEBHISYS 3,715,902

SHEET 6 0F 6 METHOD AND APPARATUS FOR OPERATING ON A BLANK OF MATERIAL, E.G., DEEP DRAWING BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates, broadly speaking, to method and apparatus for moving material in a blank toward a station on a face of the blank. This invention relates, in a particular sense, to method and apparatus for deep drawing a blank of material. More specifically, this invention relates to method and apparatus for deep drawing a blank of material, particularly solid plastic material, which increases in ductility under high hydrostatic pressure, wherein the peripheral portion of the blank is fed radially inwardly by a highly pressurized flow of viscous fluid exerting viscous drag on the surface of the blank.

2. Description of the Prior Art Prior art methods of deep drawing typically include several successive drawing operations which generally require intermediate annealing operations to remove the unwanted effects of work hardening. Further, such prior art deep drawing methods typically require the employment of a different die set for each drawing operation. These prior art deep drawing methods are time consuming and expensive when utilized to deep draw ductile material, and are even more expensive and time consuming when utilized to draw the less ductile or brittle materials.

In typical prior art deep drawing operations, the material is stretch drawn, and, as is well-known, stretch-drawing can result in unwanted, uneven, and even ruinous, thinning of the walls of the deep drawn material.

Furthermore, as is known in the deep drawing art, a most significant measurement of the effectiveness of any method of deep drawing is the ratio of the diameter of the blank of material to be drawn to the diameter of the deep drawn shell produced in a single draw. Typically, a ratio of 2:1 is considered quite good for a single draw. Obviously, however, such a ratio is quite limited when the depth of the various shell structures in present commercial usage is considered. Thus, the typical prior art method of deep drawing in a single deep draw, is not available in the production of many shell, tubular, or shell-like structures which are much in demand.

Deficiencies in prior art methods and apparatus for deep drawing have been solved in an eminently satisfactory manner by methods and apparatus disclosed in recent patents issued to the present inventor and a colleague, e.g., U. S. Pat. No. 3,379,043, U. S. Pat. No. 3,452,566, U. S. Pat. No. 3,459,021, U. S. Pat. No. 3,495,433 and U. S. Pat. No. 3,509,785.

The present invention is directed broadly to method and apparatus for operating on a blank of material, specifically to apparatus and method for moving material in a blank toward a station on the blank (e.g., to thicken the blank at said station, or to force material gathered at said station into a die), and particularly to a further improved solution to the deficiencies in prior art methods and apparatus for deep drawing.

SUMMARY OF THE INVENTION One of the objects of the present invention is to provide improved method and apparatus for moving material in a blank toward a station on the face of the blank.

Another of the objects of the present invention is to provide improved method and apparatus for deep drawing.

Yet another of the objects of the present invention is to provide improved method and apparatus for deep drawing solid plastic materials which increase in duetility under high hydrostatic pressure.

Other and further objects of the present invention will become apparent during the course of the following description and by reference to the accompanying drawings and the appended claims.

Other and further objects of the present invention will become apparent during the course of the following description and by reference to the accompanying drawings and the appended claims.

Briefly, I have discovered that the foregoing objects may be attained in one embodiment by mounting the blank to be drawn within a chamber, one face of the blank being supported by a low-friction surface, by applying a highly pressurized flow of viscous fluid along the other face of said blank, said flow of viscous fluid being directed peripherally inwardly of the blank toward a station on the face of the blank, whereby said flow pressurizes the blank sufficiently to increase the normal ductility of the blank and at the same time said flow by viscous drag action forces the material of the blank peripherally inwardly toward the station. A drawing force is applied to the station normal to the surface of the face of the blank to deep draw the blank at the station.

The foregoing objects may also be obtained, in a modification, by applying highly pressurized flows of viscous fluid along both faces of the blank directed peripherally inwardly.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 6 represents a partial vertical medial section of another form of apparatus embodying the present invention;

FIG. 7 represents a transverse section taken along the line 77 of FIG. 6;

FIG. 8 represents a chart showing pressure relationships in the viscous fluid at various radial positions in the apparatus of FIG. 6;

FIG. 9 represents a view in plan of apparatus for nonuniform drawing of material;

FIG. 10 represents a view in elevation of a representative article produced by the apparatus of FIG. 9;

FIG. 11 represents a partial vertical medial section of yet another modification;

FIG. 12 represents a section taken along the line 12-12 of FIG. 11;

FIG. 13 represents a fragmentary partial vertical medial section of a modification of the embodiment of FIG. 11; and

FIG. 14 represents a fragmentary partial vertical medial section of a further modification of the embodiment of FIG. 11.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to that form of apparatus shown in FIGS. 1 and 2, it will be seen that annular housing 1 is positioned in surrounding concentric relationship to annular housing 2, and that both annular housings l and 2 are secured by suitable means, such as welding, to end plate 3. Inner wall 4 of housing 1 and outer wall 5 of housing 2 are circularly cylindrical and define therebetween annular exterior chamber 6. Housing 2 surrounds an inner tubular member 7 which is circularly cylindrical and which defines a central bore 8. Inner wall 9 of housing 2 is circularly cylindrical and defines with tubular member 7 a circularly cylindrical annular interior chamber 10. It will be noted, particularly and for reasons which will hereinafter appear, that the tops of annular housing 1 and tubular member 7 lie in a plane which is spaced above the plane of the top of annular housing 2.

An annular driving piston 11 is closely slidably fitted within annular exterior chamber 6 and is adapted to be reciprocated in a vertical direction within said annular exterior chamber 6. A plurality of piston rods 12 is uniformly spaced around the annular driving piston 11, the upper ends of said piston rods 12 being suitably secured to said annular driving piston 11. Piston rods 12 closely slidably extend through openings 13 in end plate 3, and the lower ends of piston rods 12 are suitably secured to plate 14. Plate 14 in turn is secured to piston 15 of hydraulic cylinder 16 operated by fluid lines 17 and 18 as shown diagrammatically in FIG. 1.

It will be apparent that, when the fluid in hydraulic cylinder 16 below piston 15 is pressurized, as by con necting fluid lines 18 and 17 to the discharge and intake ports, respectively, of a pump (not shown), piston 15 and piston rods 12 will be forced upwardly, thereby forcing annular driving piston 11 upwardly within annular exterior chamber 6. Conversely, when the fluid lines 18 and 17 are connected to the intake and discharge ports, respectively, of a pump (not shown), piston 15 and piston rods 12 will be forced downwardly, thereby lowering annular driving piston l 1 downwardly within annular exterior chamber 6.

It will, of course, be understood that end plate 3 is fixedly supported by a stationary foundation (not shown).

An annular piston 19 is closely slidably fitted within annular interior chamber 10 and is adapted to be reciprocated in a vertical direction within said annular interior chamber 10. A plurality of piston rods 20 is uniformly spaced around the annular piston 19, the upper ends of said piston rods 20 being suitably secured to said annular piston 19. Piston rods 20 closely slidably extend through openings 21 in end plate 3. The lower ends of piston rods 20 are suitably secured to plate 22. Plate 22 is in turn secured to piston 23 of forcing annular piston 19 upwardly within annular in terior chamber 10. Conversely, when the fluid lines 26 and 25 are connected to the intake and discharge ports, respectively, of a pump (not shown), piston 23 and piston rods 20 will be forced downwardly, thereby lowering annular piston 19 downwardly within annular interior chamber 10.

Ram 28 is closely slidably fitted within central bore 8 and is adapted to be reciprocated within said central bore 8 between a position below the top of inner wall 7 and a position far enough above the top of inner wall 7 to perform the desired drawing operation as hereinafter described. The length of ram 28 is sufficient to permit the ram 28 to be extended upwardly sufficient to perform the desired drawing operation as hereinafter described without the bottom of ram 28 rising above the top of tubular member 7. Piston rod 29 is secured to ram 28 and closely slidably extends through opening 30 in end plate 3, through central aperture 31 in plate 22, and through central aperture 32 in piston 23. Piston rod 29 is connected to piston 33 in hydraulic cylinder 34 operated by fluid lines 35 and 36 as shown diagrammatically in FIG. 1.

Hydraulic cylinders 16, 24 and 34 are preferably constructed as sections or stages of a single housing 37 with transversely disposed dividing plates 38 mounted within the said housing 37 to define the said hydraulic cylinders 16, 24 and 34. Housing 37 is fixedly supported by a stationary foundation (not shown).

It will be apparent that, when the fluid in hydraulic cylinder 34 below piston 33 is pressurized, as by connecting lines 36 and 35 to the discharge and intake ports, respectively, of a pump (not shown), piston 33 and piston rod 29 will be forced upwardly, thereby forcing ram 28 upwardly within central bore 8. Conversely, when the fluid lines 36 and 35 are connected to the intake and discharge ports, respectively, of a pump (not shown), piston 33 and piston rod 29 will be forced downwardly, thereby lowering ram 28 within central bore 8.

End plate 3 is suitably secured to foundation plate 39 provided with opening 40 through which extend piston rods 12, 20 and 29 as shown. Columns 41, spaced around opening 40, are secured to foundation plate 39 and extend upwardly therefrom. Plate 42, secured to the upper ends of columns 41, is provided with an opening 43. Ring member 44, provided with inwardly extending upper lip and lower lip 46, is secured to plate 42 within the said opening 43.

Die member 47, positioned within ring member 44, has an outwardly extending peripheral lip 48 which projects between upper and lower lips 45 and 46 of ring member 44. Lips 45 and 46 extend inwardly to closely slidably contact the peripheral surface of die member 47. Lip 48 extends outwardly to closely slidably contact the inner peripheral surface of ring member 44. It will be seen that an expandible and contractable upper chamber 49 is defined above lip 48 and an expandible and contractable lower chamber 50 is defined below lip 48. Fluid supply lines 51 and 52 communicate with said upper and lower chambers, respectively. It will be apparent that, when fluid supply lines 51 and 52 are connected to the discharge and intake ports, respectively, of a pump (not shown), die member 47 will be forced downwardly, and, conversely, when fluid supply lines 51 and 52 are connected to the intake and discharge ports, respectively, of a pump (not shown), die member 47 will be raised.

Die member 47 has a central die opening 53 registering with ram 28 and through which a blank of material is drawn as hereinafter described.

Die member 47 is provided with a circularly cylindrical recess 54 exteriorly bounded by a sharply formed downwardly extending circular lip 55 and interiorly by a flared lip 56. Annular housing 1 is provided with a sharply formed upwardly extending circular lip 57 which is adapted to closely fit within recess 54 and to cooperate with lip 55 to form a circular punch or shear. The vertical distance between facing surfaces of lips 45 and 46 is sufficient to permit vertical displacement of die member 47 in the manner aforesaid, between a lower position in which the bottom of lip 55 is below the top of lip 57 and an upper position in which the bottom of lip 55 is above the top of tubular member 7 sufficiently to permit the insertion of a strip of material. The roof of recess 54 is provided with a lining of lowfriction material 58 such as Teflon, interposed between lips 55 and 56, the bottom surface of said low-friction material 58 preferably being coplanar with the bottom edge oflip S6.

The upper surface of die member 47 is provided, as shown diagrammatically in FIG. 1, with a plurality of spring loaded catches 59 spaced uniformly around die opening 53 and adapted to engage the surface of a drawn article and prevent the drawn article from being pulled back into the die opening 53 when ram 28 is lowered. Catches 59 have ratchet or detent portions 60 resiliently urged toward the center of die opening 53 and adapted to extend within the perimeter of said die opening 53.

Fluid pump 61 is adapted to force viscous fluid 62 from supply tank 62a through check valve 63 and opening 64 in annular housing 1 into annular exterior chamber 6, for a purpose to be described hereinafter.

A plurality of openings 65 uniformly spaced around tubular member 7 is provided through the upper wall of annular housing 2. Each opening 65 is provided with a check valve 66, as indicated diagrammatically in FIGS. 1 and 2, adapted to permit the passage of viscous fluid 62 only from annular exterior chamber 6 to annular interior chamber 10. A plurality of uniformly spaced openings 67 is provided through the upper end of the side wall of annular housing 2. Each opening 67 is provided with a check valve 68, as indicated diagrammatically in FIG. 1, adapted to permit the passage of viscous fluid 62 only from annular interior chamber to annular exterior chamber 6. It will be seen that check valves 66 and 68 are so arranged that viscous fluid 62 upon operation of annular pistons 11 and 19, as hereinafter described, will be caused to flow radially inwardly under pressure in the space 69 lying between the plane of the top of the upper wall of annular housing 2 and the plane of the top of lip 57 and tubular member 7.

Openings 67 and 64 are preferably located above the highest position of annular pistons 11 and 19.

Suitably arranged seals 70 are employed on the several pistons and elsewhere as is known in the art.

The preferred mode of operation of the apparatus shown in FIGS. 1 and 2 will now be described, it being assumed that die member 47 has been elevated to its uppermost position thereby to permit the lowermost portion of said die member 47 to clear the peripheral lip 57 around the top of annular housing 1, that annular piston 11 is in its lowermost position (as shown in solid lines in FIG. 1) and that annular piston 19 is in its uppermost position (as shown in solid lines in FIG. 1

Annular chamber 10 is filled completely with viscous fluid 62. Annular chamber 6 is filled with viscous fluid 62 up to the level of the plane of the top of tubular member 7 and lip 57. Conveniently, this may be done by removing plugs 71 in the top wall of annular housing 2, filling chamber 10 with viscous fluid 62 through openings in the top wall of annular housing 2 adapted to receive said plugs 71, by replacing said plugs 71 in said openings, and by starting pump 61 to pump viscous fluid 62 into chamber 6 to the hereinabove mentioned level. Viscous fluid 62 may advantageously be a silicone putty, which is fairly thick, in which event check valves 66, 68, 63 and pump 61 are suitably designed to handle such fluid.

Thereafter, a sheet or strip 72 of material to be drawn is placed upon lip 57 and the top of tubular member 7. Such material may advantageously be a solid plastic material, metallic or non-metallic, which term is understood by those skilled in the art as describing a material which increases in ductility, or exhibits an increased capacity for deformation without fracture, when subjected to high hydrostatic pressure, as described in Large Plastic Flow and Fracture, P. W. Bridgman (McGraw-Hill) New York 1952. The term solid plastic material," when employed in the specification and claims, is intended to refer to the material described in the immediately preceding sentence.

Die member 47 is now forcibly lowered to its bottommost position, whereupon lip 55 of die member 47 and lip 57 of annular housing 1 cooperate to shear or punch a circular blank 73 of material from sheet or strip 72, the said blank 73 bearing upwardly against low friction lining 58, the said lips 55 and 57 overlapping vertically as shown in FIG. 1.

Hydraulic cylinder 16 is operated to raise annular driving piston 11 to the position shown in phantom and simultaneously hydraulic cylinder 24 is operated to lower annular piston 19 to the position shown in phantom, the rate of decrease in volume in chamber 6 resulting from the elevation of annular driving piston 11 equaling the rate of increase in volume in chamber 10 resulting from the lowering of annular piston 19. In such manner, viscous fluid 62 in chamber 6 is highly pressurized and caused to flow through space 69 radially inwardly toward tubular member 7, and thence through check valves 66 into chamber 10. Pressurized viscous fluid 62, in flowing radially inwardly of the apparatus along the lower surface of blank 73, forces the upper surface of blank 73 against the low friction lining 58 and highly pressurizes the said blank 73, and, where the material is a solid plastic material as hereinbefore defined, the ductility of the blank 73 is thereby increased. Moreover, viscous fluid 62, in flowing radially inwardly of the apparatus, exerts a radially inwardly directed viscous drag force along the lower surface of blank 73. Inasmuch as the upper surface of blank 73 is in contact with low friction lining 58, blank 73 will be drawn or extruded radially inwardly. When the inwardly moving peripheral edge of blank 73 clears inner wall 4 of housing 1, the pressurized viscous fluid 62 acting directly on the peripheral edge of blank 73 will further assist in the inward extrusion or drawing of blank 73.

Simultaneously with the operation of hydraulic cylinders l6 and 24, hydraulic cylinder 34 is operated thereby to advance or raise ram 28 toward die opening 53. Ram 28 will engage blank 73 at a station thereon, viz., the central portion of blank 73 and will force the same through die opening 53. Ratchets or detents 60 will engage the surface of the drawn shell 74 to hold the said shell 74 while ram 28 is withdrawn, whereupon ratchets or detents 60 may be retracted and the finished shell 74 removed from the apparatus. Suitable trimming apparatus (not shown) may be mounted above die opening 53, in addition to or in place of detents 60, to trim the lower edge of shell 74 as desired.

Advantageously, the apparatus is proportioned so that only one upward stroke of annular driving piston 11 is sufficient to completely inwardly extrude blank 73 to form the finished shell 74. Alternatively, after one driving stroke as hereinbefore described, annular driving piston 11 may be lowered to the full-line position shown and annular piston 19 may be elevated to the full-line position shown, the rate of decrease of volume within annular chamber 10 resulting from the elevation of annular piston 19 equaling the rate of increase of volume within annular chamber 6 resulting from the lowering of annular driving piston 11. In this manner, viscous fluid 62 is passed from annular chamber 10 through check valves 68 to annular chamber 6. Thereupon, annular driving piston l I may be raised and annular piston 19 lowered, as first described above, to further radially inwardly extrude blank 73, it being understood that ram 28 is raised to draw blank 73 only when annular driving piston 11 is raised to force viscous fluid 62 through space 69 as hereinbefore described.

After shell 74 has been formed, ram 28 is lowered below the top of tubular member 7, and die member 47 is elevated so that lips 55 and 57 clear each other. Another portion of strip or sheet 72 may be positioned over lip 57 and the top of tubular member 7 and the operation repeated. If required, additional viscous fluid 62 may be added in an appropriate manner to chambers 6 and 10 to fill them to the desired level (viz., to the plane of the top of annular housing I and tubular member 7).

In the modification shown in FIGS. 4-and 5, means are illustrated which increase the efficiency of the system. An electrically insulating disc 75 is mounted to the top of annular housing 2. Disc 75 has a central aperture 76 which receives tubular member 7. An electrically operated heating element in the form of a disc 77, which may, for example, be made ofa nichrome alloy, is mountedto the upper surface of insulating disc 75.

Heating disc 77 has a central aperture 78 which receives tubular member 7. It will be seen that heating disc 77 is electrically insulated from annular housing 2 and structure contiguous thereto except at the area of contact between the inner faceof aperture 78 and the perimeter of tubular member 7. A plurality of apertures 79 is provided through end plate 3, annular housing 2 and insulating disc 75, said apertures being spaced uniformly around and under the peripheral portionof heating disc 77. Electrical conductors 80, electrically connected to the peripheral portion of heating disc 77 extend through apertures 79 and are electrically connected to main 81 which, in turn, is connected one side of a source 82 of electricity. An electrical connector 83 extends between the other side of the source 82 of electricity and a convenient portion of the structure'which may, for example, be end plate 3.

It will be seen that heating disc 77 is connected across the source 82 of electricity, and that electrical current will accordingly flow between the peripheral and central portions of heating disc 77 thereby to elevate the temperature thereof as desired.

With annular driving piston 11 elevated at any particular velocity, thereby to pressurize viscous fluid 62 to a particular level corresponding to said velocity, the total viscous drag force generated by the viscous fluid 62 along the lower surface of blank 73 and the upper surface of heating disc 77 will be essentially constant, a certain proportion of the viscous drag force being exerted along the lower surface of blank 73 and the balance of said viscous drag force being exerted along the upper surface of heating disc 77. When an electrical current is passed through heating disc 77 through the hereinbefore described circuitry, the temperature of disc 77 is raised, thereby raising the temperature of, and thus reducing the viscosity of, that portion of viscous fluid 62 flowing adjacent the upper surface of heating disc 7 7. In this manner, the viscous drag force exerted along disc 77 is decreased and, with annular driving piston 11 being elevated at the same particular velocity, a greater proportion of viscous drag force available at such particular velocity is now exerted along the lower surface of blank 73 thereby increasing the efficiency of the operation. It will be seen that, with annular driving piston 11 being elevated at a particular velocity, the amount of viscous drag force exerted along the lower surface of blank 73 can be adjusted by adjusting the flow of electricity through heating disc 77. It will also be seen that if a constant viscous drag force is required to be exerted along the lower surface of blank 73, by elevating the temperature of disc 77 such constant viscous drag force can be achieved with less pumping effort by annular driving piston 11 then if disc 77 were not heated (i.e., less than if there were no disc 77).

Suitable apertures 84 and 85 are provided through discs and 77, providing access to plugs 71 and communication with openings 65.

In the embodiments heretofore described, it will be apparent that the pressure in viscous fluid 62 decreases as the said fluid 62 flows radially inward in space 69.

It may be desirable, in the drawing of some materials, to employ fluid circuitry such that the average fluid pressure in viscous fluid 62 increases as the said fluid 62 flows radially inward in space 69. Such increase in average fluid pressure may be obtained by the embodiment shown in FIGS. 6 and 7 wherein two stages of fluid travel are provided, at different pressures, the higher pressure stage being located radially inward of the lower pressure stage. Thus, it will be seen that while the fluid pressure decreases in each stage as the fluid 62 flows radially inward, the overall effect is that of increasing average fluid pressure.

Apparatus for obtaining the result described in the preceding paragraph, comprises annular housing 86 positioned in surrounding concentric relationship to annular housing 87 and tubular housing 88. Housings 86, 87 and 88 are secured by suitable means, such as welding, to an end plate similar to end plate 3 of FIG. 1. The spaces between housings 86, 87 and 88 are circularly cylindrical, annular exterior chamber 89 being defined by housings 86 and 87, and annular interior chamber 90 being defined by housings 87 and 88. Housing 88 also defines a central bore 91.

An annular piston 92 is closely slidably fitted within annular exterior chamber 89 and is adapted to be reciprocated in a vertical direction within said annular exterior chamber 89. A plurality of piston rods 93 is uniformly spaced around the annular piston 92, the upper ends of said piston rods 93 being suitably secured to said annular piston 92.

An annular driving piston 94 is closely slidably fitted within annular interior chamber 90, and is adapted to be reciprocated in a vertical direction within said annular interior chamber 90. A plurality of piston rods 95 is uniformly spaced around the annular driving piston 94, the upper ends of said piston rods 95 being suitably secured to said annular driving piston 94.

Ram 96 is closely slidably fitted within central bore 91 and is provided with piston rod 97.

Piston rods 93, 95 and 97 are operatively connected to hydraulic cylinders in the same manner as the operative connection of piston rods 12, and 29 to hydraulic cylinders 16, 24 and 34, respectively, as illustrated in FIG. 1.

Annular pistons 92 and 94 are raised and lowered within their respective chambers 89 and 90, and ram 96 is raised and lowered, by operation of the hydraulic cylinders respectively operatively connected through piston rods 93, 95 and 97, to the said annular pistons 92 and 94 and ram 96.

Die member 47, only a portion of which is shown, cooperates with the structure hereinabove described, and is adapted to be reciprocated vertically as hereinbefore described. Specifically, lip 55 of die member 47 cooperates with sharply formed upwardly extending circular lip 98 on annular housing 86 to form a circular punch or shear.

A plurality of uniformly radially spaced openings 99 is provided through the upper end of housing 87 preferably located above the highest position of annular pistons 92 and 94. Each opening 99 is provided with a check valve 100, as indicated diagrammatically in FIG. 6, adapted to permit the passage of viscous fluid 62 only from annular exterior chamber 89 to annular interior chamber 90.

It will be seen, from an examination of FIG. 6, that the tops of housings 87 and 88 and the top of housing 86 whence projects lip 98 lie in a common plane. Plate 101 having a central aperture 102 adapted to closely slidably receive ram 96 is mounted in a suitable manner on the tops of housings 86, 87 and 88 so that aperture 102 registers with central bore 91. An annular ring 103 is suitably mounted to the inner periphery of lip 98 and r to the upper peripheral face of plate 101, the top of annular ring 103 being in the same plane as the top of lip 98. An annular ring 104, having a central aperture 105 adapted to closely slidably receive ram 96,'is mounted in a suitable manner to the upper face of plate 101 so that aperture 105 registers with aperture 1-02.

Annular plate 106, formed with upwardly extending annular projection 107, is suitably mounted on plate 101 between annular rings 103 and 104. It will be seen from an examination of FIG. 6, that the tops of lip 98, rings 103 and 104, and projection 107 lie in a common plane.

The upper surface of annular plate 106 is divided by projection 107 into an inner chamber 108 lying between projection 107 and annular ring 104 and an outer chamber 109 lying between annular ring 103 and projection 107. Projection 107 registers with housing 87. A plurality of radially spaced apertures 110 formed vertically through plate 106 adjacent the inner periphery of projection 107, registers with a plurality of radially spaced apertures 111 formed vertically through plate 101, thereby affording communication between annular interior chamber 90 and inner chamber 108 at a plurality of points radially spaced adjacent the inner periphery of projection 107. A plurality of radially spaced apertures 112 formed vertically through plate 106 adjacent the outer periphery of projection 107 registers with a plurality of radially spaced apertures 113 formed vertically through plate 101, thereby affording communication between annular exterior chamber 89 and outer chamber 109 at a plurality of points radially spaced adjacent the outer periphery of projection 107.

A plurality of radially spaced apertures 114 is formed vertically through plate 106 adjacent the outer periphery of ring 104. A plurality of radially spaced apertures 115 is formed vertically through plate 106 adjacent the inner periphery of ring 103. A plurality of radially spaced passages 116 is formed in plate 106 radially thereof, as best shown in FIG. 7, each passage 116 communicating at its inner end with one of apertures 114 and at its outer end with one of apertures 115.

It will be seen from the foregoing that inner chamber 108 is in communication at a plurality of points radially spaced adjacent the outer periphery of ring 104, through passages 116, with outer chamber 109 at a plurality of points radially spaced adjacent the inner periphery of ring 103.

Each opening 113 is provided with a check valve 117, as indicated diagrammatically in FIG. 6, adapted to permit the passage of viscous fluid 62 only from outer chamber 109 to annular exterior chamber 89.

It will be seen that check valves 100 and 117 are so arranged that viscous fluid 62 upon operation of annular pistons 92 and 94, as hereinafter described, will be caused to flow from annular interior chamber 90 radially inwardly under pressure in inner chamber 108 (viz., from the outer peripheral portion of inner chamber 108 adjacent the inner periphery of projection 107 toward the inner peripheral portion of inner chamber 108 adjacent the outer periphery of ring 104), thence through passages 116 radially outwardly to outer chamber 109, thence radially inwardly under lower pressure (because of pressure drop) in outer chamber 109 viz., from the outer peripheral portion of outer chamber 109 adjacent the inner periphery of ring 103 toward the inner peripheral portion of outer chamber 109 adjacent the outer periphery of projection 107), and thence to annular exterior chamber 89.

In order to fill the apparatus as hereinafter described, fluid pump 61 is connected through check valve 63 to opening 64 in housing 86 communicating with annular exterior chamber 89 for the introduction of viscous fluid 62 thereto from supply tank 62a. Venting means required in the filling operation are provided by openings 118 through plates 101 and 106, which shown in FIGS. 6- and 7 is generally similar to the operation previously described for the apparatus of FIGS. 1 and 2.

Thus, annular chambers 89 and 90 are filled completely with viscous fluid 62, and inner and outer chambers 108 and 109 are also filled with viscous fluid 62 up to the level of the tops of rings 103 and 104 and projection 107..

Thereafter, a sheet or strip 72 of material isplaced upon lip 98 and the tops of rings 103 and 104 and projection 107. Then, die member 47 is forcibly lowered to its bottommost portion, whereupon lip 55 of die member 47 and lip 98 of housing 86 shear a circular blank 73 of material from sheet or strip 72,. the said blank 73 bearing upwardly against low friction lining 58, the said lips 55 and 98 overlapping as shown in FIG. 6.

Annular driving piston 94 has until this point been at its lowermost position, and annular piston 92'at its uppermost position. The hydraulic cylinders operatively associated with annular pistons 94 and 92 are now actuated to raise annular driving piston 94 and simultaneously to lower annular piston 92, the rate of decrease in volume in annular chamber 90 equaling the rate of increase in volume in annular chamber 89. In such manner, viscous fluid 62 in the hereinbefore described chambers is highly pressurized and caused to flow radially inwardly in inner chamber 108 and thence radially inwardly in outer chamber 109. Viscous fluid 62, in flowing radially inwardly in inner chamber 108 against the lower surface of blank 73, forces the upper surface of blank 73 against the low friction lining 58 and highly pressurizes the said blank 73 and where the material is a solid plastic material as hereinbefore defined, the ductility of the blank 73 is thereby increased. At the same time, viscous fluid 62 in flowing radially inwardly in inner chamber 108, exerts a radially inwardly directed viscous drag force along the lower surface of blank 73. Viscous fluid 62, in flowing radially inwardly in outer chamber 109, likewise highly pressurizes the said blank 73 (but to a lesser degree because of pressure drop in the viscous fluid 62) and exerts a radially inwardly directed viscous drag force along the lower surface of blank 73.

Simultaneously with the foregoing, ram 96 is advanced toward die opening 53 in die member 47, thereby to draw blank 73 in the said die opening 53.

An idealized plot of pressure as a function of radial distance is shown in FIG. 8. The solid lines represent the pressure in viscous fluid 62 when in contact with blank 7'3. The dashed line represents the pressure in viscous fluid 62 when flowing through passages 116 from the inner peripheral portion of inner chamber 108 to the outer peripheral portion of outer chamber 109. FIG. 8 is vertically superposed over FIG. 6 so that zero on the X-axis registers with the longitudinal axis of the apparatus. If the center of each solid line is taken as the average fluid pressure in each of chambers 108 and 109, and if such centers are joined by a line as shown in phantom so as to indicate relative average fluid pressures in the chambers 108 and 109, it will be seen that the average fluid pressure in the viscous fluid 62 moving radially inwardly of the apparatus while contacting and exerting viscous drag force on blank 73 increases in such direction of movement.

In the embodiments heretofore described, the preferred configuration of die opening 53 is cylindrical, and the material in blank 73 has been drawn uniformly radially inwardly into the said die opening 53 to produce circularly cylindrical shell 74.

It should be understood that the invention is not to be limited to the production of circularly cylindrical shells 74. Rather, cylindrical shells of other shapes, regular or irregular, can be drawn by means of the present invention. In such instance, die opening 53 and matching rams 28 and 96, would have the appropriate configuration.

It should also be understood that the present invention may be employed to draw material into a die opening in a non-uniform manner, which is of particular interest when the depth of the product may not be uniform. Such application is shown in FIGS. 9 and 10. In FIG. 9, fluid inlet apertures 120 and fluid outlet apertures 121 are provided within a chamber 122 of apparatus indicated generally as 123. It will be understood that apparatus 123 may otherwise generally conform to the apparatus shown in FIG. 1, that suitable means are provided to force pressurized viscous fluid throughapertures 120 into chamber 122, that suitable means are provided to withdraw viscous fluid from apertures 122, that a sheet of material to be drawn is supported over apparatus 123, that a ram 124 may be extended from opening 125 in apparatus 123 to draw material into a corresponding die opening in a die member superposed over apparatus 123 and having a low friction lining against the bottom surface of which bears the upper surface of the material. It will be seen that the flow of pressurized viscous fluid in chamber 122, from apertures 120 to apertures 121, pressurizes the said material and exerts inwardly directed viscous drag force along the lower surface of the material in the direction of the arrows shown in FIG. 9. The ram 124, having an inclined upper force draws the material as shown in FIG. 10. The non-uniform path of the viscous fluid permits more of the material to be inwardly extruded toward the deeper end of the drawn portion 126 of the finished article 127 In the modification shown in FIGS. 11 and 12, flows of viscous fluid 62 are applied along both faces of blank' 73. Those elements of structure shown below strip 72 in FIG. 1 are employed in this modification, except that it is now preferred that annular housing 1 be provided with sharply formed upwardly extending circular lip 128 about its outer perimeter as shown.

Die member 129, positioned within ring member 44, has an outwardly extending peripheral lip 48 cooperating with upper and lower lips 45 and 46 of ring member 44 in the manner described for the embodiment of FIG. 1, so that, upon suitably connecting fluid supply lines 51 and 52 to the discharge and intake ports, respectively, of a pump (not shown), die member 129 will be forced downwardly or upwardly, as desired.

Die member 129 essentially duplicates the structure shown below strip 72, as will be apparent from an inspection of FIG. 11.

Thus, die member 129 comprises annular housing 130 positioned in surrounding concentric relationship to annular housing 131, the latter being secured by suitable means, such as welding, to transverse element 132. Inner wall 133 of housing 130 and outer wall 134 of housing 131 are circularly cylindrical and define therebetween annular exterior chamber 135. Housing 131 surrounds an inner tubular member 136 which is circularly cylindrical and which defines a central die opening 137. Inner wall 138 of housing 131 is circularly cylindrical and defines with tubular member 136 a circularly cylindrical annular interior chamber 139. It will be noted, particularly and for reasons which will hereinafter appear, that the bottoms of annular housing 130 and tubular member 136 lie in a plane which is spaced below the plane of the bottom of annular housing 131.

An annular driving piston 140 is closely slidably fitted within annular exterior chamber 135 and is adapted to be reciprocated in a vertical direction within said annular exterior chamber 135. Four piston rods 141 are uniformly spaced around the annular driving piston 140, the lower ends of said piston rods 141 being suitably secured to said annular driving piston 140. Piston rods 141 closely slidably extend through openings 142 in transverse element 132, and the upper ends of piston rods 141 are suitably secured to plate 143. Plate 143, in turn, is secured to piston 144 of hydraulic cylinder 145 operated by fluid lines 146 and 147 as shown diagrammatically in FIG. 1 1.

In will be apparent that, when the fluid in hydraulic cylinder 145 above piston 144 is pressurized, as by connecting fluid lines 146 and 147 to the discharge and intake ports, respectively, of a pump (not shown), piston 144 and piston rods 141 will be forced downwardly, thereby forcing annular driving piston 140 downwardly within annular exterior chamber 135. Conversely, when the fluid lines 146 and 147 are connected to the intake and discharge ports, respectively, of a pump (not shown), piston 144 and piston rods 141 will be forced upwardly, thereby raising annular driving piston 140 within annular exterior chamber 135.

An annular piston 148 is closely slidably fitted within annular interior chamber 139 and is adapted to be reciprocated in a vertical direction within said annular interior chamber 139. Four piston rods 149 are uniformly spaced around the annular piston 148, the lower ends of said piston rods being suitably secured to said annular piston 148. Piston rods 149 closely slidably extend through openings 150 in transverse element 132. The upper ends of piston rods 149 are suitably secured to plate 151. Plate 151 is in turn secured to piston 152 of hydraulic cylinder 153 operated by fluid lines 154 and 155 as shown diagrammatically in FIG. 11. Piston 152' closely slidably extends through central aperture 156 in piston 144.

It will be apparent that when the fluid in hydraulic cylinder 153 above piston 152 is pressurized as by connecting fluid lines 154 and 155 to the discharge and in take ports, respectively, of a pump (not shown), piston 152 and piston rods 149 will be forced downwardly, thereby forcing annular piston 148 downwardly within annular interior chamber 139. Conversely, when the fluid lines 154 and 155 are connected to the intake and discharge ports, respectively, of a pump (not shown), piston 152 and piston rods 149 will be forced upwardly, thereby raising annular piston 148 upwardly within annular interior chamber 139.

Central die opening 137 within tubular member 136 is sufficient to accommodate finished shell 74 being advanced upwardly therethrough by ram 28, as shown in phantom in FIG. 11. In this regard, it should be noted that ram 28 is of length sufficient to permit the said ram 28 to be extended upwardly to perform the desired drawing operation as hereinafter described without the bottom of ram 28 rising above the top of tubular member 7. In other words, ram 28 is long enough to permit the top thereof to project above transverse element 132 to the underside of the head of topmost shell 74 shown in phantom in FIG. 11 while the bottom of ram 28 is below the top of tubular member 7.

Hydraulic-cylinders 145 and 153 are preferably constructed as sections or stages of a single housing 157 with transversely disposed dividing plate 158 mounted within the said housing 157 'to define the said hydraulic cylinders 145 and 153. Housing 157 is fixedly supported on die member 129 by suitable means (not shown).

Die member 129 is provided with a sharply form-ed downwardly extending lip 159 adapted to cooperate with lip 128 to form a circular punch or shear. The vertical distance between joining surfaces of lips 45 and 46 is sufficient to permit vertical displacement of die member 129, in the manner aforesaid, between a lower position in which the bottom of lip 159 is below the top of lip 128 and an upper position in which the bottom of lip 159 is above the top of lip 128 and tubular member 7 sufficiently to permit the insertion of a strip of material.

The upper surface of transverse element 132 is provided, as shown diagrammatically in FIGS. 11 and 12, with a pair of spring loaded catches 59 adapted to engage the surface of shell 74 and prevent shell 74 from being pulled back into the die opening 137 when ram 28 is lowered. Catches 59 have ratchet or detent portions 60 resiliently urged toward the center of die opening 137 and adapted to extend within the perimeter of said die opening 137.

Fluid pump 160 is adapted to force viscous fluid 62 from supply tank 62b through check valve 161 and opening 162 in annular housing 130 into annular exterior chamber 135, for a purpose to be described hereinafter.

A plurality of openings 163 uniformly spaced around tubular member 136 is provided throughthe lower wall of annular housing 134. Each opening 163 is provided with a check valve 164, as indicated diagrammatically in FIG. 11, adapted to permit the passage of viscous fluid 62 only from annular exterior chamber 135 to annular interior chamber 139. A plurality of uniformly spaced openings 165 is provided through the lower end of the side wall of annular housing 131. Each opening 165 is provided with a check valve 166, as indicated diagrammatically in FIG. 11, adapted to permit the passage of viscous fluid 62 only from annular interior chamber 139 to annular exterior chamber 135. It will be seen that check valves 164 and 166 are so arranged that viscous fluid, upon operation of annular pistons 140 and 148 as hereinafter described, will be caused to flow radially inwardly under pressure in the space 167 lying between the plane of the bottom of the lower wall of annular housing 131 and the plane of the bottom of tubular member 136.v

Openings 163 and 165 are preferably located below the lowest position of annular pistons 140 and 148.

Check valves 161, 164 and 166, and pump 160 are suitably designed to handle viscous fluid 62 which may, as hereinbefore mentioned, advantageously be a silicone putty.

The preferred mode of operation of the apparatus shown in FIGS. 11 and 12 will now be described, it being assumed that die member 129 has been elevated to its uppermost position thereby to permit the lowermost portion of said die member 129 to clear the peripheral lip 128 around the top of annular housing 1, that annular piston 11 is in its lowermost position, that annular piston 19 is in its uppermost position (as shown in solid lines in FIG. 11), and that annular chambers 6 and 10 have been filled with viscous fluid 62 as hereinbefore described.

Hydraulic cylinders 145 and 153 are operated to elevate annular piston 148 to its uppermost position (as shown in phantom in FIG. 11) and to lower annular piston 140 to its lowermost position (as shown in phantom in FIG. 11). Annular interior chamber 139 is now filled with viscous fluid .62 through a suitable opening (not shown), suitable venting means (likewise not shown) being provided in the upper portion of annular interior chamber 139.

Thereafter, a sheet or strip of material 72 to be drawn is placed upon lip 128 and the top of tubular member 7.

Die member 129 is now forcibly lowered to its bottommost position whereupon lip 159 of die member 129 and lip 128 of annular housing 1 cooperate to shear or punch a circular blank 73 of material from sheet or strip 72, the bottom edge of tubular member 136 engaging the upper surface of blank 73, and lips 128 and 159 overlapping as shown.

Hydraulic cylinders 145 and 153 are now operated to elevate annular piston 140 to its uppermost position (as shown in solid lines in FIG. 11) and to lower annular piston 148 to its lowermost position (as shown in solid lines in FIG. 11), whereupon the major portion of viscous fluid 62 in annular interior chamber 139 enters annular exterior chamber 135 and thence space 167 through openings 165 and check valves 166. Pump 160 is then operated to complete the filling of annular exterior chamber with viscous fluid 62, suitable venting means (not shown) being provided in the upper portion of annular exterior chamber 135.

The actual drawing operation is now commenced. Annular driving pistons 11 and are respectively raised and lowered, simultaneously and at the same rate, and, simultaneously, annular pistons 19 and 148 are respectively lowered and raised, simultaneously and at the same rate, the rate of decrease in volume in chambers 6 and 135 resulting from the respective raising and lowering of annular driving pistons 11 and 140 equaling the rate of increase in volume, respectively, of chambers 10 and 139 resulting from the respective lowering and raising of annular pistons 19 and 148. In such manner, viscous fluid 62 in chambers 6 and 135 is highly pressurized and caused to flow through space 69 below blank 73 and space 167 above blank 73 radially inwardly of said blank 73 towards tubular members 7 and 136, viscous fluid 62 in space 69 then flowing through check valves 66 into chamber 10 and viscous fluid in space 167 then flowing through check valves 164 into chamber 139. Pressurized viscous fluid 62, in flowing radially inwardly of the apparatus along the upper and lower surfaces of blank 73 highly pressurizes the blank 73, and, where the material is a-solid plastic material as h ereinbefore defined, the ductility of the blank is thereby increased. Moreover, viscous fluid 62, in flowing radially inwardly of the apparatus, exerts radially inwardly directed viscous drag force along the upper and lower surfaces of blank 73, thereby drawing or extruding blank 73 radially inwardly. When the inwardly moving peripheral edge of blank '73 clears inner wall 4 of housing 1, viscous fluid 62 acting directly on the peripheral edge of blank 73 will further assist in the inward extrusion or drawing of blank 73.

Simultaneously with the foregoing, ram 28 is advanced or raised toward die opening 137. Ram 28 will engage blank 73 at a station thereon, viz., the central portion of blank 73 and will force the same up through die opening 137. As the peripheral edge of blank 73 is about to clear the space between the upper end of tubular members 7 and 136, the upward and downward movements, respectively, of annular driving pistons 11 and 140 are stopped, thereby to avoid driving viscous fluid 62 into die opening 137. The upward movement of ram 28 is continued until shell 74 emerges from the top of die opening 137 (as shown in phantom in FIG. 11). .Ratchets or detents 60 engage the surface of the drawn shell 74 to hold the said shell 74 whereupon ram 28 is withdrawn from shell 74 and lowered to a position below the top of tubular member 7. Ratchets or detents 60 may be retracted, and the finished shell 74 removed from the apparatus between piston rod 149 in the general direction indicated by the arrow in FIG. 12. Alternatively, finished shell 74, while engaged by ratchets or detents 60, can be forced out from such engagement by a force directed along the arrow indicated in FIG. 12.

Advantageously, the apparatus of FIG. 11 is so proportioned that only one upward stroke of annular driving piston 11 and only one simultaneous downward stroke of annular driving piston 140 are necessary to completely inwardly extrude blank 73 to form the finished shell 74. Alternatively, after the initial driving strokes hereinbefore described, annular driving pistons 11 and 140 may be lowered and raised, respectively, and annular pistons 19 and 148 may be simultaneously raised and lowered, respectively, the rate of decrease of volume within chambers and 139 resulting from the respective raising and lowering of annular pistons 19 and 148 equaling the rate of increase of volume within annular chambers 6 and 135 resulting from the respective lowering and raising of annular pistons 11 and 140. In this manner, viscous fluid 62 is passed from annular chamber 10 through check valves 68 to annular chamber 6 and from annular chamber 139 through check valves 166 to annular chamber 135. Thereupon, annular driving pistons 11 and 140 may be raised and lowered respectively, and annular pistons 19 and 148 simultaneously lowered and raised, respectively, as first described above, to further radially inwardly extrude blank 73, it being understood that ram 28 is raised to draw blank 73 only when viscous fluid 62 is forced through spaces 69 and 167 as hereinbefore described.

It will be recognized at this point that, as blank 73 is radially inwardly drawn and the peripheral edge thereof clears the inner wall 4 of housing 1, viscous fluids 62 from above and below the blank 73 will be in contact.

After shell 74 has been formed and ram 28 lowered below the top of tubular member 7, die member 129 is elevated so that lips 128 and 159 clear each other. Depending upon the fluidity of viscous fluid 62, some of the viscous fluid 62 may run out of chamber 135 during this operation, and any such losses are readily subsequently made up by means of pump 160. With very stiff viscous fluid 62, such as silicone putty, virtually none will be lost during this operation. Forceful upward movement of die member 129 will cause the merged bodies of viscous fluid 62 within joined spaces 69 and 167 to shear therewithin; by providing constriction 168 at the bottom of chamber 135 as shown in FIG. 11, the merged bodies of viscous fluid 62 will always separate at such minimum area location.

Another portion of strip or sheet 72 may be positioned over housing 1, and the operation, commencing with the lowering of die member 129 repeated. Pump 160 is operated to supply any required makeup of viscous fluid 62 to chamber 135.

An excess of viscous fluid 62 may accumulate in chamber 10 below blank 73, caused by the heretofore merged bodies of viscous fluid 62 separating above the normal level of blank 73 viz., at the level of constriction 168). That volume of viscous fluid lying between the level of constriction 168 and the normal level of blank 73 must be vented from chamber 10 when die member 129 is lowered so as to punch blank 73 from strip 72 and force blank 73 to its normal level as shown in FIG. 11. Suitable means for venting are well known. One such means may employ valve 169 in the line between check valve 63 and opening 64, which valve 169 is opened only during this stage of operation (viz., when die member 129 is lowered).

Electrically operated heating elements similar to, and for the same purpose as, that illustrated in the modification of FIGS. 4 and 5 may likewise be employed in a modification of the embodiment of FIGS. 11 and 12, as shown in FIG. 13. That portion of the apparatus shown below blank 73 in FIG. 13 corresponds with that portion of apparatus shown below blank 73 in FIG. 4. Apparatus elements identified by prime numerals above blank 73in FIG. 13 correspond respectively with and are operated in the same manner and for the same purpose as, apparatus elements identified by unprimed numerals below blank 73 in FIG. 13. The operation and purpose of heating element 77 have already been fully described in connection with FIGS. 4 and 5.

The plural staging of fluid circuitry shown in the embodiment of FIGS. 6 and 7, whereby average fluid pressure in viscous fluid 62 is caused to increase inwardly, may likewise be employed in a modification of the embodiment of FIGS. 11 and 12, as shown in FIG. 14. That portion of the apparatus shown below blank 73 in FIG. 14 corresponds with that portion of apparatus shown below blank 73 in FIG. 6. Apparatus elements identified by primed numerals above blank 73 in FIG. 14 correspond respectively with, and are operated in the same manner and for the same purpose as, apparatus elements identified by unprimed numerals below blank 73 in FIG. 13. The principle of operation has been adequately described in connection with FIGS. 6and 7.

Further, the modification of FIGS. 11 and 14 may be employed to draw material into a die opening in a nonuniform manner according to FIGS. 9 and 10.

It will be seen from all of the foregoing that novel method and apparatus are disclosed for moving material in a blank toward a station on the blank and for deep drawing the blank by exerting a drawing force normal to the blank at the said station.

What is claimed is:

1. Method of moving material in a blank, having a substantially planar first face and a substantially planar second face opposite said first face, toward a station on the first face of said blank, said method comprising:

a. frictionally exerting drag force along the first face of said blank directed inwardly from the periphery of said blank toward said station;

b. simultaneously with step (a), applying supporting force normal to the second face of said blank while permitting said second face to move freely in the plane of said second face.

2. Method as in claim 1, wherein:

c. said drag force is directed toward said station around the entire perimeter of said station.

3. Method as in claim 1, wherein:

c. said blank is circular,

d. said station is at the center of said blank and has a circular perimeter,

. said drag force is directedradially inwardly from the edge of said blank toward the perimeter of said station around the entire said perimeter of said station.

4. Method as in claim 1, wherein:

c'. the material constituting the said blank is solid plastic material;

said method further comprising:

(1. simultaneously with steps (a) and (b), subjecting said blank to pressure of magnitude sufficient to increase the ductility of said blank.

5. Method as in claim 4, wherein:

e. the magnitude of said pressure is increased in the direction of said station.

6. Method of moving material in a blank, having a substantially planar first face and a substantially planar second face opposite said first face, toward a station on the first face of said blank, said method comprising:

e. the magnitude of said pressure is increased in the direction of said station.

17. Method as in claim 11, wherein:

c. said viscous fluid is flowed between the first face of a. frictionally exerting drag force along the first face of said blank directed inwardly from the periphery of said blank toward said station;

b. simultaneously with step (a), supporting the second face of said blank with a low-friction sur face.

7. Method as in claim 6, wherein:

c. said drag force is directed toward said. station around the entire perimeter of said station.

8. Method as in claim 6, wherein:

c. said blank is circular,

11. said station is at the center of said blank and has a circular perimeter,

e. said drag force is directed radially inwardly from the edge of said blank toward the perimeter of said station around the entire said perimeter of said station.

9. Method as in claim 6, wherein:

c. the material constituting the said blank is solid plastic material;

said method further comprising:

(1. simultaneously with steps (a) and (b), subjecting said blank to pressure of magnitude sufficient to increase the ductility of said blank.

10. Method as in claim 9, wherein:

e. the magnitude of said pressure is increased in the direction of said station.

11. Method of moving material in a blank, having a said blank and a second surface spaced from said first face of said blank;

said method further comprising:

d. adjusting the viscosity of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

18. Method as in claim 11, wherein:

c. said viscous fluid is flowed between the first face of said blank and a second surface spaced from said first face of said blank,

said method further comprising:

d. adjusting the temperature of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the viscosity of said portion of viscous fluid adjacent said second surface whereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

19. Method as in claim 11, wherein:

c. said viscous fluid is flowed between the first face of said blank and a second surface spaced from said first face of said blank,

said method comprising:

d. adjusting the temperature of said second surface thereby to adjust the temperature of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the viscosity of said portion of said viscous fluid adjacent said second surface whereby to adjust the magnitude of viscous substantially planar first face and a substantially planar second face opposite said first face, toward a station on the first face of said blank, said method comprising:

drag force exerted along the first face of said blank. 20. Method as in claim 11, wherein:

a. applying a flow of viscous fluid along the first face of said blank directed toward said station, said flow of viscous fluid exerting viscous drag force along the first face of said blank directed toward said station;

b. simultaneously with step (a), applying supporting force normal to the second face of said blank while permitting said second face to move freely in the plane of said second face.

12. Method as in claim 1 1, wherein:

c. said flow of viscous fluid is directed inwardly from the periphery of said blank toward said station.

13. Method as in claim 11, wherein:

c. said flow of viscous fluid is directed toward said station around the entire perimeter of said station.

14. Method as in claim 11, wherein:

c. said flow of viscous fluid is applied in cyclically interrupted flow portions along the flrst face of said blank.

21. Method as in claim 20, wherein:

d. the average fluid pressure in a flow portion adjacent said station is greater than the average fluid pressure in a flow portion remote from said station.

22. Method as in claim 20, wherein:

d. said flow portions surround said station.

23. Method as in claim 20, wherein:

d. a flow portion remote from said station surrounds a flow portion adjacent said station,

c. said flow portion adjacent said station surrounds said station.

24. Method of moving material in a blank, having a c. said blank is circular, d. said station is at the center of said blank and has a circular perimeter,

substantially planar first face and a substantially planar second face opposite said first face, toward a station on 5 the first face of said blank, said method comprising:

e. said flow of viscous fluid is directed radially inwardly from the edge of said blank toward the perimeter of said station around the entire said perimeter of said station.

15. Method as in claim 11, wherein:

c. the material constituting the said blank is solid plastic material,

said method further comprising:

d. pressurizing said flow of viscous fluid sufficiently to subject said blank to pressure of magnitude sufficient to increase the ductility of said blank.

16. Method as in claim 15, wherein:

a. applying a flow of viscous fluid along the first face of said blank directed toward said station, said flow of viscous fluid exerting viscous drag force along the first face of said blank directed toward said station;

b. simultaneously with step (a), supporting that portion of the second face of said blank with a lowfriction surface.

25. Method as in claim 24, wherein:

c. said flow of viscous fluid is directed inwardly from the periphery of said blank toward said station.

26. Method as in claim 24, wherein:

c. said flow of viscous fluid is directed toward said station around the entire perimeter of said station.

27. Method as in claim 24, wherein:

c. said blank is circular,

d. said station is at the center of said blank and has a circular perimeter,

e. said flow of viscous fluid is directed radially inwardly from the edge of said blank toward the perimeter of said station.

28. Method as in claim 24, wherein:

c. the material constituting the blank is solid plastic material,

said method further comprising:

d. pressurizing said flow of viscous fluid sufficiently to subject said blank to pressure of magnitude sufficient to increase the ductility of said blank.

29. Method as in claim 28, wherein:

e. the magnitude of said pressure is increased in the direction of said station.

30. Method as in claim 24, wherein:

c. said viscous fluid is flowed between the first face of said blank and a second surface spaced from said first face of said blank,

said method further comprising:

d. adjusting the viscosity of that portion of said viscous fluid flowing adjacent said second surface whereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

31. Method as in claim 24, wherein:

c. said viscous fluid is flowed between the first face of said blank and a second surface spaced from said first face of said blank,

said method further comprising:

d. adjusting the temperature of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the viscosity of said portion of viscous fluid adjacent said second surface whereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

32. Method as in claim 24, wherein:

c. said viscous fluid is flowed between the first face of said blank and a second surface spaced from said first face of said blank,

said method further comprising:

d. adjusting the temperature of said second surface thereby to adjust the temperature of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the viscosity of said portion of viscous fluid adjacent said second surface whereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

33. Method as in claim 24, wherein:

c. said flow of viscous fluid is applied in cyclically interrupted flow portions along the first face of said blank.

34. Method as in claim 33, wherein:

d. the average fluid pressure in a flow portion adjacent said station is greater than the average fluid pressure in a flow portion remote from said station.

35. Method as in claim 33, wherein:

d. said flow portions surround said station.

36. Method as in claim 33, wherein:

d. a flow portion remote from said station surrounds a flow portion adjacent said station.

e. said flow portion adjacent said station surrounds said station.

37. Method of deep drawing a blank of material, said blank having a substantially planar first face and a substantially planar second face opposite said first face, said method comprising:

a. frictionally exerting drag force along the first face of said blank toward a station on said blank to move material of said blank toward said station;

b. simultaneously with step (a), exerting a drawing force on said blank at said station thereby to deep draw said blank.

38. Method as in claim 37, wherein:

c. said drag force is directed inwardly from the periphery of said blank toward said station.

39. Method as in claim 37, wherein:

c. said drag force is exerted toward said station around the entire perimeter of said station.

40. Method as in claim 37, wherein:

c. said blank is circular,

d. said station is at the center of said blank and has a circular perimeter,

. said drag force is directed radially inwardly from the edge of said blank toward the perimeter of said station around the entire perimeter of said station.

41. Method as in claim 37,

said method further comprising:

c. simultaneously with step (a), applying supporting force normal to that portion of the second face of said blank outside the perimeter of said station while permitting said portion to move freely in the plane of said second face.

42. Method as in claim 37,

said method further comprising:

c. simultaneously with step (a), supporting that portion of the second face of said blank outside the perimeter of said station with a low-friction surface.

43. Method as in claim 37 wherein:

c. the material constituting the said blank is solid plastic material;

said method further comprising:

d. simultaneously with steps (a) and (b), subjecting said blank to pressure of magnitude sufficient to increase the ductility of said blank.

44. Method as in claim 43, wherein:

e. the magnitude of said pressure is increased in the direction of said station.

45. Method of deep drawing a blank of material, said blank having a substantially planar first face and a substantially planar second face opposite said first face, said method comprising:

a. applying a flow of viscous fluid along the first face of said blank, directed toward a station on said blank, said flow of viscous fluid exerting viscous drag force along the first face of said blank directed toward said station, said viscous drag force moving material of said blank toward said station;

b. simultaneously with step (a), exerting a drawing force on said blank at said station thereby to deep draw said blank.

46. Method as in claim 45, wherein:

c. said flow of viscous fluid is directed inwardly from the periphery of said blank toward said station.

47. Method as in claim 45, wherein:

c. said flow of viscous fluid is directed toward said station around the entire perimeter of said station.

48. Method as in claim 45, wherein:

c. said blank is circular, v

d. said station is at the center. of said blank and has a circular perimeter,

e. said flow of viscous fluid is directed radially inwardly from the edge of said blank toward the perimeter of said station around the entire perimeter of said station.

49. Method as in claim 45,

said method further comprising:

c. applying supporting force normal to that portion of the second face of said blank outside the perimeter of said station while permitting said portion to move freely in the plane of said second face.

50. Method as in claim 45,

said method further comprising:

c. supporting that portion of the second face of said blank outside the perimeter of said station with a low-friction surface.

51. Method as in claim 45, wherein:

c. the material constituting the said blank is solid plastic material,

said method further comprising:

d. pressurizing said flow of viscous fluid sufficiently to subject said blank to pressure of magnitude sufficient to increase the ductility of said blank.

52. Method as in claim 51, wherein:

e. the magnitude of said pressure is increased in the direction of said station.

53. Method as in claim 45, wherein:

c. said viscous fluid is flowed between the first face of the blank and a second surface spaced from said first face of the blank,

said method further comprising:

(1. adjusting the viscosity of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

54. Method as in claim 45, wherein:

c. said viscous fluid is flowed between the first face of the blank and a second surface spaced from said first face of the blank,

said method further comprising:

d. adjusting the temperature of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the viscosity of said portion of said viscous fluid adjacent said second surface whereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

55. Method as in claim 45, wherein:

c. said viscous fluid is flowed between the first face of the blank and a second surface spaced from said first face of the blank,

said method further comprising:

d. adjusting the temperature of said second surface thereby to adjust the temperature of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the viscosity of said portion of said viscous fluid adjacent said second surface whereby to adjust the magnitude of viscous drag force exerted along the first face of said blank.

56. Method as in claim 45, wherein:

c. said flow of viscous fluid is applied in cyclically interrupted flow portions along the first face of said blank.

57. Method as in claim 56, wherein:

d. the average fluid pressure in a flow portion adjacent said station is greater than the average fluid pressure in a flow portion remote from said station.

58. Method as in claim 56, wherein:

d. said flow portions surround said station.

59. Method as in claim 56, wherein:

d. a flow portion remote from said station surrounds a flow portion adjacent said station,

e. said flow portion adjacent said station surrounds said station.

60. Apparatus for moving material in a blank, having a substantially planar first face and a substantially planar second face opposite said first face, toward a station on the first face of said blank, said apparatus comprising: i

a. first means adapted to frictionally exert drag force along the first face of said blank directed inwardly from the periphery of said blank toward said station;

b. second means adapted to support the second face of said blank, said second means being further adapted to permit said second face to move freely in the plane of said second face.

61. Apparatus as in claim 60, wherein:

c. said first means is adapted to exert said drag force toward said station around the entire perimeter of said station.

62. Apparatus as in claim 60 for operating on a circular blank having a station with a circular perimeter at the center of said blank, wherein:

c. said first means is adapted to exert said drag force redially inwardly from the edge of said blank toward the perimeter of said station around the entire said perimeter of said station.

63. Apparatus as in claim 60 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means for applying pressure to said blank to increase the ductility of said blank.

64. Apparatus as in claim 60 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means for applying pressure to said blank increasing in the direction of said station to increase the ductility of said blank.

65. Apparatus for moving material in a blank, having a substantially planar first face and a substantially planar second face opposite said first face, toward a station on the first face of said blank, said apparatus comprising:

a. first means adapted to frictionally exert drag force along the first face of said blank directed inwardly from the periphery of said blank toward said station,

b. a low-friction surface adapted to engage and support the second face of said blank.

66. Apparatus as in claim 65, wherein:

c. said first means is adapted to exert said drag force toward said station around the entire perimeter of said station.

67. Apparatus as in claim 65, wherein:

c. said first means is adapted to exert said drag force radially inwardly from the edge of a circular blank toward the perimeter of a circular station around the entire said perimeter of said station.

68. Apparatus as in claim 65 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means for applying pressure to said blank to increase the ductility of said blank.

69. Apparatus as in claim 65 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means for applying pressure to said blank in-. creasing in the direction of said station to increase the ductility of said blank.

70. Apparatus for moving material in a blank, having a substantially planar first face and a substantially planar second face opposite said first face, toward a station on the first face of said blank, said apparatus comprising:

a. first means adapted to apply a flow of viscous fluid along the first face of said blank directed toward said station thereby to exert viscous drag force along the first face of said blank directed toward said station;

. second means adapted to support the second f ce of said blank, said second means being further adapted to permit said second face to move freely in the plane of said second face.

71. Apparatus as in claim 70, wherein:

c. said first means is adapted to direct said flow inwardly from the periphery of said blank toward said station.

72. Apparatus as in claim 70, wherein:

c. said first means is adapted to direct said flow toward said station around the entire perimeter of said station.

73. Apparatus as in claim 70, for operating on a circular blank having a station with -a circular perimeter in the center of said blank, wherein:

c. said first means is adapted to direct said flow radially inwardly from the edge of said blank toward the perimeter of said station around the entire said perimeter of said station.

74. Apparatus as in claim 70 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means adapted to pressurize said flow of viscous fluid to apply sufficient pressure to said blank to increase the ductility of said blank.

75. Apparatus as in claim 70 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means adapted to pressurize said flow of viscous fluid to apply sufficient pressure to said blank increasing in the direction of said station to increase the ductility of said blank.

76. Apparatus as in claim '70, said apparatus further comprising:

c. a second surface spaced from said first face of said blank,

(1. said first means being adapted to direct said flow between said second surface and said first face of said blank,

e. viscosity adjustment means to adjust the viscosity of that portion of said viscous fluid flowing adjacent said second surface thereby to adjust the 6 f. said viscosity adjustment means comprises means to adjust the temperature of that portion of said viscous fluid flowing adjacent said second surface.

78. Apparatus as in claim 76, wherein:

f. said viscosity adjustment means comprises means to adjust the temperature of said second surface thereby to adjust the temperature of that portion of said viscous fluid flowing adjacent said second surface.

79. Apparatus as in claim 70, wherein:

c. said first means is adapted to apply said flow of viscous fluid in cyclically interrupted flow portions along said first face of said blank.

80. Apparatus as in claim 79, wherein:

d. said cyclically interrupted flow portions comprise a first flow portion adjacent said station and having a first average pressure and a second flow portion remote from said station and having a second average pressure, said second average pressure being lower than said first average pressure.

81. Apparatus as in claim 79, wherein:

d. said flow portions surround said station.

82. Apparatus as in claim 80, wherein:

e. said first flow portion surrounds said station,

f. said second flow portion surrounds said first flow portion.

83. Apparatus for moving material in a blank, having a substantially planar first face and a substantially planar second face opposite said first face, toward a station on the first face of said blank, said apparatus comprising:

a. first means adapted to apply a flow of viscous fluid along the first face of said blank directed toward said station thereby to exert viscous drag force along the first face of said blank directed toward said station,

(b) a low-friction surface adapted to engage and support the second face of said blank. 84. Apparatus as in claim 83, wherein:

c. said first means is adapted to direct said flow inwardly from the periphery of said blank toward said station.

85. Apparatus as in claim 83, wherein:

c. said first means is adapted to direct said flow toward said station around the entire perimeter of said station.

86. Apparatus as in claim 83 for operating on a circular blank having a station with a circular perimeter in the center, wherein:

c. said first means is adapted to direct said flow radially inwardly from the edge of a circular blank toward the perimeter of a circular station around the entire said perimeter of said station.

87. Apparatus as in claim 83 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means to pressurize said flow of viscous fluid to apply sufficient pressure to said blank to increase the ductility of said blank.

88. Apparatus as in claim 83 for operating on a blank of solid plastic material, said apparatus further comprising:

c. third means adapted to pressurize said flow of viscous fluid to apply sufficient pressure to said blank increasing in the direction of said station to increase the ductility of said blank.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3910086 *Oct 19, 1973Oct 7, 1975Vladislav Ivanovich ErshovMethod and means for shaping parts by hydraulic extrusion
US4011744 *Feb 25, 1975Mar 15, 1977Ivanovich Ershov VladislavMethod and means for shaping parts by hydraulic extrusion
US5157969 *Nov 29, 1989Oct 27, 1992Armco Steel Co., L.P.Apparatus and method for hydroforming sheet metal
US5372026 *Mar 23, 1992Dec 13, 1994Armco Steel CompanyApparatus and method for hydroforming sheet metal
US5413118 *Aug 20, 1990May 9, 1995Baxter International Inc.Surgical drapes for covering appendages
US5555761 *May 30, 1995Sep 17, 1996Minster Machine CoBodymaker tool pack
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Classifications
U.S. Classification72/60, 72/347
International ClassificationB21D22/20
Cooperative ClassificationB21D22/20
European ClassificationB21D22/20
Legal Events
DateCodeEventDescription
Mar 19, 1984ASAssignment
Owner name: AT & T TECHNOLOGIES, INC.,
Free format text: CHANGE OF NAME;ASSIGNOR:WESTERN ELECTRIC COMPANY, INCORPORATED;REEL/FRAME:004251/0868
Effective date: 19831229