|Publication number||US2622874 A|
|Publication date||Dec 23, 1952|
|Filing date||Aug 21, 1948|
|Priority date||Aug 21, 1948|
|Publication number||US 2622874 A, US 2622874A, US-A-2622874, US2622874 A, US2622874A|
|Original Assignee||John Haller|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (12), Referenced by (19), Classifications (5)|
|External Links: USPTO, USPTO Assignment, Espacenet|
J. HALLER 2,622,874
INTERMITTENT RECIPROCATORY FEEDING APPARATUS 2 SHEETS-SHEET 1 Dec. 23, 1952 Filed Aug. 21, 1948 mQ @9 S QQ Dec. 23, 1952 J. HALLER INTERMITTENT RECIPRCCATORY FEEDING APPARATUS 2 SHEETS--Sl-IEET 2 Filed Aug. 21, 1943 Illllllx Patented Dec. 23, 1952 UNITED STATES PATENT OFFICE INTERMITTENT RECIPROCATORY FEEDING APPARATUS This invention relates to material feeding arrangements and, in particular to arrangements for feeding sheet material or coil stock intermittently to processing machines utilizing such material, such as punch presses, or stamping or shearin machines.
One object of this invention is to provide an intermittent feedin arrangement for sheet or coil material wherein the material is engaged by clamps actuated by hydraulic fluid, the flow of which is controlled by a hydraulic device attached to the machine, thereby bringing about an almost instantaneous response of the feeding mechanism to the motion of the machine.
Another object is to provide an intermittent feeding arrangement of the foregoing character for sheet or coil material wherein the machine being served is provided with a pair of hydraulically operated clamping devices, one of which is station-arily mounted on the machine bed and the other mounted on a reciprocable slide, the clamping devices being alternately engaged so that the sheet material is advanced intermittently, the clamping devices being operated by hydraulic fluid, the flow of which is controlled in response to the action of a hydraulic pump attached to a moving part of the machine being served.
Another object is to provide an intermittent feeding arrangement of the foregoin character for sheet or coil material wherein the pressure fluid for intermittently actuating the material clamping devices is supplied from a hydraulic pump or other suitable source, the flow of pressure fluid being controlled by a valve which in turn is actuated by a servo-motor hydraulically connected to a hydraulic piston and cylinder device connected to a moving part of the machine being served, a sequence valve being preferably included in the circuit to defer operation of the hydraulic feeding motor until a predetermined pressure has been built up in the clamping circuit.
In the drawings:
Figure 1 is a side elevation, partly in section, of a feeding arrangement for sheet material, attached to a punch press, accordin to a preferred form of the invention;
Figure 2 is a top planview of the feeding arrangement shown in Figure 1;
Figure 3 is a vertical cross-section taken along the line 3-3 in Figure 1, showing the details of one of the hydraulic clamps;
Figure 4 is a diagrammatic central longitudinal section through the four-way valve shown 5 Claims. (Cl. 271-25) '2 in side elevation at the lower right-hand of Figure 1;
Figure 5 is a fragmentary Side elevation of a control device slightly modified from that shown in the upper left-hand corner of Figure 1 so as to operate the feeding mechanism on the downstroke of the machine, rather than on the upstroke as in Figure 1; and
Figure 6 is a side elevation, partly in longitudinal section, of a sequence valve preferably used in the hydraulic circuit shown in Figures 1 and 2.
Referring to the drawingsin detail, Figure v1 shows a sheet metal working machine, generally designated Ill, such as a punching or stamping press, adapted to be served by an automatic feeding arrangement, generally designated ll, according to a preferred form of the present invention. The machine It) is conventional andthe details form no part of the present invention. As shown diagrammatically in Figure 1, the ma.- chine l 6 consists of a bed l2 having vertical guide members l3 secured thereto by means not shown and serving to reciprocably guide a platen [4. The machine in is provided with a base or bed [5 to which is bolted a die .unit It having a pair of die cavities l1 and I8 cooperable with punches l9 and 20 of a punch unit 21 secured to the lower end of the platen I4.
Bolted or otherwise secured to the platen I 4 is the horizontal arm 22 of an L-shaped bracket 23 to the vertical arm 24 of which a cam plate 25 is adjustably secured. For this purpose the .cam plate 25 is provided with a pair of vertically? spaced arms 26 bored to receive the bracket arm 24 and having set screws 21 threaded into the ends thereof to engage and clamp thecam plate 25 in any position of adjustment vertically along the bracket 23. The cam plate 25. is provided with a zig-zag cam groove 28 having an upper horizontal portion 29 connected by an inclined portion 30 to a lower horizontal portion 3|. v,
Mounted in the cam groove 28 is a roller or cam follower 32 which in turn rotates upon an axle 33 mounted on the end of a piston rod. 34 of a motive device generally designated 35. The latter is connected to the guide member l3 by a bracket 36 bolted thereto, and consists of a casing 31 having a reservoir 38 in the upper portion thereof closed by a cover plate 39 and connected by a passageway 4!} to a valve chamber 5! containing a check valve or relief valve 42. The latter is urged downwardly into a seat 43 by a coil corner spring 441, the upper end of which engages a plug 45 threaded into the upper end of the valve chamthe cylinder 52.
her 4|. The valve chamber 4| below the valve seat 43 is connected by a passageway 45 to the right-hand end of a cylinder bore 41 having an outlet port 48 in one end thereof. Reciprocably mounted in the cylinder bore 41 is a piston head 49 which, in turn, is mounted upon the piston rod 34. The reservoir 39 is directly connected to the left-hand end of the cylinder bore 4'! by a passageway 50; 'I'heireservoir 33 contains a suitable hydraulic liquid, such as oil.
Extending downwardly from the port 48 to a port 5| in the cylinder 52 of a servomotor 53 is a fluid supply pipe 54 which servesto convey hydraulic fluid to and from the motive device 35. The servomotor 53 has a cylinder bore 55 which is considerably less in volume. than. the cylinder bore 47 of the motive device 35, so that a crowding effect is obtained. By this crowding effect, the excess fluid not required to operate the servomotor 53 is discharged through theportsAS: and and-thecheck valve back into the reservoir 38, an extremely rapid action beingobtained by-this arrangement. The servomotor bore 55 contains a piston. 55 mounted on a piston rod- 5'! extending through one end of The piston-56 is urged toward the right by a coil spring 58, the opposite end of which is engaged by the end of an adjusting screw 50 which is threaded through a bore 60 in one end ofthe servomotor cylinder 52.
The servomotor piston 5! is connected to the outer end of a valve rod 6| which isreciprocably mounted in a standard four-way control valve 62. The four-way control valve 62 is conventional and well-known among hydraulic engineers, and its'detail s form no part of the present invention. A'ny suitable type of reversing valve may be used in place of thefour-way valve 62 and a brief description of. its principal features, as shown in Figure 4, will suffl'ce. The three-headed hollow valve spool 63 reciprocates in a valve bore 64 Figu-re 4) which is provided with spaced ports 'to which are connected a central pressure fluidsupply. pipe 65, pressure fluid service pipes 65 andGI on opposite sides thereof, and a pressure' fluid discharge or exhaust pipe 68 connected to the-cylinder bore 64 near the ends thereof so as to be covered by the end heads of the valve spool 63 when the valve is in its neutral position. The pressure fluid supply pipe 65 is connected to a suitable hydraulic pump (not shown) and the pipe 68 leads to a fluid reservoir (not shown) from-which the pump draws its fluid. The control valve 62 and servomotor 53 areboth mounted on a bracketfifl which is bolted. to the underside of the feeding mechanism bed 70' (Figure 1) which in turn is bolted to the machine bed I5. The feeding mechanism bed 10' supports the feeding mechanism, generally designated II, by which the sheet stock or coil stock S is fed to the machine I 0.
Rising from the left-hand end of the bed I is an-upright I2 in the form of a metal block having a flat'top surface I3 over which the sheet stock S slides. The stock S is guided by grooved guide wheels 14 mounted on studs I which are in turn threaded into slides 16 slidably mounted inT-shaoed grooves 11 so as to adapt the guide wheels I4 to varying widths of stock S. Set screws 18 serve to secure the slides E6 in the r adjusted positions. The T-shaped grooves 11 are'formed in a forwardly-extending and overhanging.- p'ortionlS forming a part of the upright 12 The upright 12 and its surface 13 form the lower portion of a stationary clamp generally designated which is intermittently operated to alternately clamp and release the stock S in cooperation with a movable clamp BI of similar construction. The clamps 80 and 8| are disclosed and claimed in my co-pending application Serial No. 734,904 filed March 15, 1947 on which was granted the Haller patent No. 2,467,740 issued April 19, 1949 for Step-by StepFeeding Device. and. their details form no part of the present invention.
The clamps 80 and 8I are of similar construction, hence a single description will be suflicient for both. Each clamp is provided with a blocklike' casing 82 having a port 83 into which is threaded a pipe connection 84. The pipe connection 04 of the stationary clamp 80 is connected to the service pipe 61, whereas the connection 84 of the movable clamp BI is connected by a flexible pipe 85 to the service pipe 66. The movable clamp 8| has a block-like base 86 corresponding-to the block-like upright 12 and having a similar flat surface 81 at the top thereof over which the stock S slides.
The port 83 opens into a downwardly-inclined passageway-88 (Figure 1) leading to a laterallyelongated chamber 89 closed by an elongated plate 90 bolted to the casing 82. Leading downwardly from the chamber 89 are inclined multiple bores 9| containing reciprocable plunger pins 92 (Figure 2). The plungers 92 are urged downward in the bores 9| by coil springs 93, and their lower ends engage an elongated roller 94 which is mounted in a tapering recess 95 having an upper wall surface 96 inclined downward toward the walls or surfaces 13 or 81 over which the stock S slides. The clamps 80 and N are each provided with a slot 01 extending therethrough for the passage of the stock S (Figure 3). Bolts 98 extend downward through the casing 82' to secure it to the upright 12 or base 88 as the case maybe (Figure 1).
The upright 12' is provided with horizontallyspaced sockets 99 for receiving'the forward ends of spaced parallel guide rods I00, the rearward ends of which are mounted in bores IOI in arms I02 extending laterally outward from the cylinder I03 of the hydraulic feeding cylinder or motor I04. The motor I04 is of the variable stroke type disclosed and claimed in my Patent No. 2,428,493 issued Oct. 7, 1947 for Stock Feeding Mechanism for Punching, Stamping and Cutting Machines.
The cylinder I03 of the motor I04 has a cylinder bore I05 in which reciprocates a compound adjustable stroke piston generally designated I06. The latter consists of a hollow piston rod I01 (Figure l) the outer end of which is reduced in diameter and, after passing through a bore I08 in the clamp base 86, terminates in a threaded portion carrying a nut I09. The inner end of. the piston rod I01 carries a head H0.
The piston rod I01 is provided with an internally-threaded bore III into which is threaded a threaded stem I I2 of a movable piston head I i 3, this, in turn, being bored longitudinally with a bore of square cross-section adapted to slidably receive a square shaft H4 carrying a hand wheel H5 at its outer end and a similarly-bored collar I I 0 located on the inner side of the cylinder head Ill. The opposite ends of the cylinder bore I05 are provided with ports H8 and IIS into which are threaded branches of the service pipes 66 and 6! respectively. Thus, by rotating the hand wheel II5, the piston heads H0 and II 3 may be '5 caused to move toward or away from one another, thereby lengthening or shortening the stroke of the compound piston I06 in the cylinder bore I05.
In order to guide the movable clamp 8| in its reciprocation, the base thereof is bored as at I20 (Figure 3) for the passage of the guide rods 00. The rearward portion of the stock S is also guided by grooved guide wheels 14 similar to those previously described and similarly numbered and similarly mounted on studs 15 carried by slides 16 reciprocating in T-slots 11 formed in arm portions I2I extending laterally outward from the upper rearward end of the cylinder I02 (Figure 2).
To insure that the sheet or strip S of material will be grasped with sufficient pressure to prevent slippage before the feeding stroke commences, a sequence valve, generally designated I25 (Figures 1 and 6) is preferably inserted in each of the service pipes 66 and 61, along with a check valve I23. The sequence valve I25 consists of a casing I21 having a longitudinal bore I28 terminating at one end in a plunger lifting bore I29 of reduced diameter having a passageway I30 extending from the outer end thereof back to the intake port I 3! which leads into an annular enlargement E32 from which the outlet port I33 leads outward. Both of these ports are connected to gaps in the service pipes 66 and 61 so as to be in series therewith. The annular enlargement I32 forms a part of the lower end of the bore I28, which portion, for convenience, will be designated as the chamber I32.
Surrounding the bore I28 above the chamber I32 and spaced away from it is an annular enlargement I34 from which an auxiliary port or sequence port I35 opens outward. Pipes I36 and I31 run from the sequence valves I25 in the service pipes 66 and 61 respectively to the opposite end ports H8 and III! of the hydraulic feeding motor I04 (Figure 2). Bolted to the upper end of the bore I28 is a cap I38 having a smaller threaded bore I39 extending longitudi nally thereof co-axial with the bore I28. Threaded into the bore I39 is an adjusting screw I40 having a socket MI in the lower end thereof adapted to receive the upper end of a coil spring I42, the lower end of which engages the upper end of a valve plunger I43 and urges it downward. A lock nut I44 locks the screw I40 in its adjusted position for regulating the force exerted by the coil spring I42 upon the valve plunger I43 whereas a cap I45 with a socket I46 therein covers the otherwise exposed end I41 of the screw I40.
The valve plunger I43 is of approximately cylindrical form with heads I48 and I49 separated from one another by a reduced diameter neck I50 lying within the chamber I32. The lower end of the valve plunger I43 is engaged by a plunger-lifting piston I5I which is reciprocable in the plunger-lifting bore I29.
In the operation of the clamping arrangement shown in Figures 1 to 4 inclusive, the sheet or coil stock S is threaded through the slots 91 in the movable and stationary clamps 8| and 80 as shown in Figure 1, and the hand wheel II5 rotated to adjust the stroke of the hydraulic motor I04 to the desired feeding stroke for the stock S, depending upon the size of workpiece to be stamped or punched out by the punch unit 2 I. The operator then starts the hydraulic pump (not shown) which supplies hydraulic pressure fluid through the supply pipe 65 to the four-way con- 6 trol valve 62, which in turn actuates the fixed and movable clamps and 8I alternately as well as actuating the hydraulic motor I04 to advance the stock S.
The operator now starts the machine I0 causing the platen I4 to descend and punch out a workpiece from the stock S. As the platen I4 rises, it carries the cam plate 25 upward, causing the inclined portion 30 of the cam groove 28 to engage the roller 32 on the end of the piston rod 34 and shift the piston 49 to the right. Assuming the cylinder bore 41 to be full of fluid, this fluid is forced under pressure through the pipe 54 into the right-hand end of the cylinder bore 55 of the servo-motor 53, shifting its piston 56 and piston rod 51, as well as the valve rod SI of the four-way control valve 62 to the left, compressing the coil spring 58. When the valve rod 6| and three-headed spool 63 are thus shifted to the left to the opposite position from that shown in Figure 4, pressure fluid from the supply pipe 55 can pass directly into the service pipe 68, since the middle head of the valve spool 53 is now to the left of the supply pipe 85.
The pressure fluid passing through the pipe 66 enters the annular enlargement or chamber I32 through the inlet port I3I and passes outward through the outlet port I 33 into the remainder of the pipe 89 and thence through the flexible pipe into the clamp chamber 89 of the movable clamp BI. There it acts against the upper ends of the plungers 92, forcing them downward and causing the roller 94 to be wedged tightly into the converging chamber 95. This causes the roller 04 to react against the inclined surface 98 so as to force the stock S tightly into frictional engagement with the surface 81 of the base 86 of the movable clamp 8 I.
Meanwhile, a portion of the pressure fluid in the service pipe 56 has passed through the passageway I30 (Figure 6) of the first (right hand) sequence valve I 25 (Figure 2) into the lower end of the plunger-lifting bore 529 where it acts against the lower end of the piston I5I. When the pressure has risen to a point where the force exerted on the piston i5i is able to overcome the force of the coil spring I42, it shifts the valve plunger I43 upward, causing the head I49 to pass above the annular enlargement or chamber I34 so that the space around the neck I50 interconnects the annular enlargements or chambers I32 and I34. Pressure fluid then flows from the chamber I32 through this spaced and outward through the auxiliary port I35, thence through the pipe line I33 to the port H8. The pressure thus entering the right-hand end of the cylinder bore 505 of the feeding motor I04, acts against the compound piston head H3 and shifts it, the piston rod I01 and the movable clamp BI to the left, shifting the stock S to the left.
The clamp BI continues to move the stock S a distance equal to the length of stroke of the compound piston I06, whereupon it halts. Throughout all of this feeding movement, of course, the stationary clamp 80 has been in its released position because the service pipe 51 leading thereto has been connected through the second sequence valve I25 and through the control valve 52 to the exhaust pipe 68. Thus, there is no pressure at this time in the chamber 89 of the stationary clamp 80, hence the roller 94 thereof fails to tightly grip the stock S as it slides past, propelled by the moving clamp 81. At the same time, the fluid displaced from the left-hand end of the, motor cylinder Hi3 escapes through the pipe I31 and check valve E26 into the service pipe 6'! and thence, in the manner stated above, to the exhaust pipe 58.
When the platen l4 reaches the top of its stroke and starts downward upon a punching stroke, the foregoing motions are reversed. The downward travel of the platen l4 causes the cam groove of the cam plate 25 to move the piston rod 34 of the motive device 35 to its left-hand position as shown in Figure 1. This, in turn, creates a suction in the pipe 54 and right-hand end of the servo-motor cylinder bore 55, permitting the coil spring 58 to shift the servo-motor piston rod El, valve rod ti and valve spool 53 of the control valve 82 to the right into the position shown in Figures 1 and 4. This reverses the flow of the pressure fiuid in the supply pipe (35 from the service pipe 5 to the service pipe 3?.
This action actuates the clamp to cause its roller 94 to tightly grip the stool: S and hold it stationary against the surface it on the upright 12. When the pressure within the chamber 89 of the fixed clamp 8i! rises to an amount sufficient for the piston Edi to overcome the force of the coil spring M2 and lift the plunger i i-S thereof, in the second sequence valve 525 located in the service pipe pressur fluid is then enabled to flow from the pipe through the bore 28 to the enlargement lite and out through the auxiliary port Hi5 and pipe #3? to the port H9 at the left-hand Cl" the cylinder I03 of the hydraulic motor 1%. Thus, the fixed clamp 851 securely grips the stool: S before the hydraulic motor 5 becomes operativc to retract the movable clamp Ell back to its starting point. When pressure fluid from the branch 13? of the pipe 6? enters the port HS the left-hand end of the cylinder bore of the feeding motor lot, it retracts the compound piston l 6% and the movable clamp 85 to the right into the positions shown in Figure 1. Since the service pipe 65 is now connected to the discharge or exhaust line '58, no pressure exists in the chamber 85 of the movable clamp 8!, hence the roller 9 thereof releases its grip on the stock. S now temporarily held by the stationary clamp 89 and permits it to slide thereof while the movable clamp 8! is being retracted. Meanwhile, the fluid displaced from the right-hand end of the cylinder 33 of the hydraulic motor lu l escapes through the port HE, auxiliary line Hi8 and check valve I26 into the service pipe now connected to the exhaust pipe 68, as stated above. The platen I l continues its downward. stroke and the punch unit 2! punches out another workpiece, after which the platen i4 moves upward and the foregoing cycle of operations is repeated.
As previously stated, the cylinder bore 3? of the motive device 35 is of considerably larger capacity than the servo-motor cylinder bore Accordingly, during the first part of the stroke of the piston head t9, the servo-motor cylinder bore 55 is rapidly filled as its piston head moves to the left. The excess fluid in the cyl nder bore a? is then discharged through the port 66, lifting the ball check valve or relief valve 42 against the thrust of the coil spring and causing the excess fluid to escape through the port into the reservoir 33.
The modification shown in Figure 5 is similar to the corresponding portion shown in the upper left-hand corner of Figure 1, except that the direction of the cam groove 28 is reversed in the cam plate 25. The motive device 35 remains exactly the same. In the operation of the modi-. fication shown in Figure 5, however, the motive piston 39 moves to the left on the upstroke of the platen M and to the right on the downstroke thereof, exactly the reverse of the motion in Figures 1 to 4 inclusive. The remainder of the circuit and mechanism of Figure 5 are the same, except that the stock S is advanced on the downstroke of the platen l4 and held stationary on the upstroke thereof. It is, of course, obvious that all motion of the stock S should cease before the punches I9 and 20 reach it.
What I claim is:
1. An intermittent feeding arrangement for feeding sheet material to a press having a 'reciprocable material-processing member, said arrangement comprising a stationary material support, a movable material support, a pressure-fluid-actuated clamp mounted adjacent each support and having a clamping member movable hydraulically into clamping engagement with said material against its respective support, a hydraulic motor operatively connected to said movable support to move the same, a pressure-fluid distributor hydraulically connected to said clamps and to said hydraulic motor, a servo-motor operatively connected to said pressure fluid distributor to shaft the same, a pressure-fluid pump hydraulically connected to said servo-motor and mechanism operatively connecting said material processing member to said pump whereby the motion of said materialprocessing member shifts said servo-motor to responsively shift said distributor and, supply pressure fluid alternately to said clamps and to the opposite sides of said motor.
2. An intermittent feeding arrangement for feeding sheet material to a press having a reciprocable material-processing member, said arrangement comprising a stationary material support, a movable material support, a pressure-fluid-actuated clamp mounted adjacent each support and having a clamping member movable hydraulically into clamping engagement with said material against its respective sup port, a hydraulic motor operatively connected to said movable support to move the same, a pressure-fluid distributor hydraulically connected to said clamps and to said hydraulic motor, a cam device operatively connected to said material-processing member, a sermo-motor operatively connected to said pressure fluid distributor to shift the same, and a pressure fluid pump hydraulically connected to said servomotor and operatively engageable with said cam device whereby the motion of said materialprocessing member shifts said servo-motor ;to responsively shift said distributor and supply pressure fluid alternately to said clamps and to the opposite sides of said motor.
3. An intermittent feeding arrangement for feeding sheet material to a press having a reciprocable material-processing member, said arrangement comprising a stationary material support, a movable material support, a pressure-fluid-actuated clamp mounted adjacent each support and having a clamping member movable hydraulically into clamping engagement with said material against its respective support, a hydraulic motor having a cylinder and a reciprocable piston therein operatively connected to said movable support to m th same, a pressure-fluid distributor hydraulically connected to said clamps and to said hydraulic motor, said pressure-fluid distributor having a pair or" alternatively selective service ports either of which becomes a pressure-fluid delivery port while the other service port becomes a fluid return port, a servo-motor operatively connected to said pressure-fluid distributor to shift the same, a pressure-fluid pump hydraulically connected to said servo-notor, mechanism operatively connecting said material processing member to said pump whereby the motion of said material-processing member shifts said'distributor to supply pressure fluid alternately to said clamps and to the opposite ends of said cylinder, one of said service ports being hydraulically connected to one end of said cylinder and to one of said clamps and the other service port being hydraulically connected to the other end of said cylinder and to the other of said clamps.
4. An intermittent feeding arrangement for feeding sheet material to a press having a reciprocable material-processing member, said arrangement comprising a stationary material support, a movable material support, a pres sure-fluid-actuated clamp mounted adjacent each support and having a clamping member movable hydraulically into clamping engagement with said material against its respective support, a hydraulic motor having a cylinder and a reciprocable piston therein operatively connected to said movable support to move the same, a pressure-fluid distributor hydraulically connected to said clamps and to said hydraulic motor, a servo-motor operatively connected to said pressure fluid distributor to shift the same, a pressure fluid pump hydraulically connected to said sermo-motor and mechanism operatively connecting said material processing member to said pump whereby the motion of said material-processing member shifts said servo-motor to responsively shift said distributor and supply pressure fluid alternately to said clamps and to the opposite ends of said cylinder.
5. An intermittent feeding arrangement for feeding sheet material to a press having a reciprocable material-processing member, said arrangement comprising a stationary material support, a movable material support, a pressure-fluid-actuated clamp mounted adjacent each support and having a clamping member movable hydraulically into clamping engagement with said material against its respective support, a hydraulic motor operatively connected .to said movable support to move the same, a pressure-fluid distributor hydraulically connected to said clamps and to said hydraulic motor, said pressure-fluid distributor having a pair of alternatively selective service ports either of which becomes a pressure-fluid delivery port while the other service port becomes a fluid return port, a servomotor operatively connected to said pressure-fluid distributor to shift the same, a pressure-fluid pump hydraulically connected to said servomotor, mechanism operatively connecting said material processing member to said pump whereby the motion of said material-processing member shifts said distributor to supply pressure fluid alternately to said clamps and to the opposite sides of said motor, one of said service ports being hydraulically connected to one side of said motor and to one of said clamps and the other service port being hydraulically connected to the other side of said motor to the other clamp, and a sequence valve connected between each clamp and its respective side of said motor and having a yieldingly-urged valve member therein shiftable in response to a predetermined rise in pressure in said clamp to divert pressure fluid to said motor whereby to exert a predetermined clamping grip on said material before permitting said motor to shift said material.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 2,096,073 Spencer Oct. 19, 1937 2,166,428 Clark July 18, 1939 2,301,028 Esch Nov. 3, 1942 2,347,261 Harrington et al. Apr. 25, 1944 2,354,860 Hartsock et al. Aug. 1, 1944 2,367,248 Vickers et al Jan. 16, 1945 2,379,002 Haller June 26, 1945 2,406,508 Papsdorf Aug. 27, 1946 2,409,968 Welsch Oct. 22, 1946 2,428,493 Haller Oct. 7, 1947 2,467,740 Haller Apr. 19, 1949 2,470,252 Kyle May 17, 1949
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US2096073 *||Nov 23, 1935||Oct 19, 1937||Western Electric Co||Work holding device|
|US2166423 *||May 4, 1936||Jul 18, 1939||Max J Clark||Hydraulic device|
|US2301028 *||Jul 27, 1940||Nov 3, 1942||Vickers Inc||Power transmission|
|US2347261 *||Sep 23, 1939||Apr 25, 1944||Vickers Inc||Power transmission|
|US2354860 *||Apr 23, 1942||Aug 1, 1944||Mid West Hydro Pierce Inc||Tube perforating machine|
|US2367248 *||Jun 29, 1939||Jan 16, 1945||Vickers Inc||Oil well pumping machinery|
|US2379002 *||Apr 26, 1944||Jun 26, 1945||John Haller||Automatic feed mechanism for punching and stamping presses|
|US2406508 *||Mar 2, 1945||Aug 27, 1946||Papsdorf Robert A||Self-acting stock feed|
|US2409968 *||Aug 24, 1945||Oct 22, 1946||American Hoist & Derrick Co||Machine for operating on materials|
|US2428493 *||Feb 8, 1945||Oct 7, 1947||John Haller||Stock feeding mechanism for punching, stamping, and cutting machines|
|US2467740 *||Mar 15, 1947||Apr 19, 1949||John Haller||Step-by-step feeding device|
|US2470252 *||Nov 9, 1945||May 17, 1949||Pelton Water Wheel Co||Hydraulic pumping jack with control responsive to abnormal conditions|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US2711818 *||Dec 9, 1953||Jun 28, 1955||Western Electric Co||Apparatus for feeding simultaneously a plurality of wires|
|US2727236 *||Jun 22, 1953||Dec 20, 1955||Klumpp Jr Ferdinand||Apparatus for assembling terminals with a twin conductor cable|
|US2776048 *||Jul 19, 1952||Jan 1, 1957||Nat Machinery Co||Stock feeding apparatus|
|US2825560 *||Aug 19, 1955||Mar 4, 1958||Danly Mach Specialties Inc||Grip feed|
|US2871911 *||Jan 13, 1953||Feb 3, 1959||Glastrusions||Apparatus for producing elongated articles from fiber-reinforced plastic material|
|US2978158 *||Oct 24, 1955||Apr 4, 1961||Herr Equipment Corp||Feed apparatus|
|US2978160 *||Sep 21, 1956||Apr 4, 1961||Special Engineering Service In||Press feed mechanism|
|US3035813 *||Apr 18, 1960||May 22, 1962||Alois Horel||Tensioning device for wires or cables|
|US3038645 *||Jul 6, 1959||Jun 12, 1962||Mechanical Tool & Engineering||Stock feed mechanism|
|US3051361 *||Aug 10, 1959||Aug 28, 1962||Design Ct Inc||Feeding apparatus and method|
|US3073499 *||Oct 28, 1958||Jan 15, 1963||Warner Brothers Co||Press for forming continuous planar thermoplastic sheet material|
|US3094263 *||May 9, 1961||Jun 18, 1963||Wills||Constant control material feeding mechanism|
|US3123270 *||Apr 19, 1962||Mar 3, 1964||figures|
|US3125270 *||Mar 15, 1962||Mar 17, 1964||Press feed mechanism|
|US3140032 *||Jun 5, 1962||Jul 7, 1964||Power Control Products Inc||Pneumatic stock feed arrangement|
|US3157334 *||Sep 24, 1962||Nov 17, 1964||Special Engineering Service In||Stock feeder|
|US4312469 *||Feb 1, 1980||Jan 26, 1982||Rune Nilsson||Feeding apparatus|
|US4444346 *||Mar 1, 1982||Apr 24, 1984||Scribner Albert W||Pneumatic feeder for punch presses|
|US4513899 *||Aug 10, 1982||Apr 30, 1985||Plessey Incorporated||Stock feeder with adjustable width feed path|
|International Classification||B21D43/11, B21D43/04|