US 3304757 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
3,304,757 MACHINE FOR ROLLING ARCUATE SHEET METAL SHAPES Filed April 6, 1964 Feb. 21-, 1967 H. s. ACHLER ETAL 2 Sheets-Sheet 1 @Yoward warold 92% 9X @Qys.
2 Sheets-Sheet 2 H. S. ACHLER ET AL lllllll.
MACHINE FOR ROLLING ARCUATE SHEET METAL SHAPES TQM Feb. 21, 1967 Filed April 6, 1964 United States Patent 3,304,757 MACHINE FOR ROLLING ARCUATE SHEET METAL SHAPES Howard S. Achler and Harold Kaufmann, both of (1hrcago, EL, assignors to Kaufmann Tool and Engineering (Zorp., a corporation of Illinois Filed Apr. 6, 1964, Ser. No. 357,413 4 Claims. (Cl. 72-166) This invention relates to a machine for rolling arcuate sheet metal shapes and more particularly to a two-roller machine for rolling sheet metal substantially without flat spots.
The rolling of sheet metal to obtain arcuate forms has been in use for many years. Except for roll-type forming of very thin metal foils, in the range of thickness of .0005 inch or only slightly more, where the mere advancing of the foils around or against a hard tool or forming member causes the sheet to take a set leading to the easy forming of generally cylindrical shapes, or where the metal foil because of its thinness or other characteristics very easily conforms to and practically adheres to the surface of a mandrel or roller being used to effect the forming of the sheet, the only machine heretofore for successfully rolling heavier sheet metal in gauge size, such as up to a thickness of 16 gauge steel have required at least three rollers, such as in a pinch roll machine or in a pyramid roll machine.
With both pinch roll machines and pyramid roll machines, the metal sheet that has been rolled is not truly arcuate and the apparently arcuate shape actually comprises a series of distinct flat segments that only tend to approximate an arcuate shape. The use of such three roller machines always produces flats whose lengths are relatively long since they are a function of either the spacing between the points of tangency between pairs of rollers where the three rolls have two pairs of tangents, or the spacing from the feed rollers to a deflecting roller. Many attempts have been made to correct the condition of flats obtaining from such machines, but such attempts cause additional expenses and frequently do not fully correct the condition.
Another deficiency with three-roller machines is that the ends of the sheet are never properly subjected to the simultaneous bending action of all three rollers and, therefore, the ends are always relatively elongated flats which require special consideration.
Thus, one object of this invention is to provide a tworoller machine for rolling sheet metal where the machine operates to achieve improved arcuity of shape in the formed sheet metal, where the arcuity is different in kind from that previously achievable in that with lighter gauge sheets the flats virtually cannot be noticed and with heavier gauge sheets such as 20 gauge the flats are only 3 to 5 times the thickness of the metal.
Another object of this invention is to provide a tworoller machine for rolling sheet metalwhere the entire sheet which is passed through the machine is uniformly formed or rolled, thereby avoiding the straight segments at the ends of sheets that occur with three-roller machines.
A further object of this invention is to provide a new and improved two-roller machine for rolling sheet metal, which machine is characterized by its simplicity and inexpensiveness of construction and by its superiority of performance.
Further objects of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.
3,304,757 Patented Feb. 21, 1967 For a better understanding of the invention, reference may be had to the accompanying drawing, in which:
FIGURE 1 is a top plan fragmentary view of a sheet metal rolling machine embodying the features of our invention;
FIGURE 2 is a cross-sectional view taken on line 2-2 of FIG. 1 and showing the rollers in full open position;
FIGURE 3 is a cross-section View of the two rollers of the machine illustrating their action on a piece of sheet metal;
FIGURE 4 is an enlarged fragmentary cross-sectional view taken substantially on line 44 of FIG. 1.
One of the important factors in being able to design the improved two-roller sheet metal rolling machine hereinafter described is the use of urethane rubber as the working surface of the driving roller of the machine. Urethane rubber, manufactured and sold by Du Pont under the trademark Adiprene has certain desirable characteristics such as unusually high load bearing capacity, abrasion resistance and oil resistance. Under loadings from relatively rigid, non-deformable members, the extreme resiliency of urethane rubber permits it to temporarily deform to a precise shape corresponding to the shape of the deforming member, and furthermore, the non-compressible characteristic of the urethane rubber and its ability to perform like a confined hydraulic fluid exerting pressure substantially uniformly along its area of contact with a deforming member provides for attaining arcuity in bends not previously attainable with any other resilient or deformable material.
Referring now the drawings, there is shown in FIGS. 1 and 2 a two-roller machine for rolling sheet metal. The machine, generally indicated at 10, includes a base 12, a drive means 14, the two-roller assembly 16, and a support shelf, or feed table, 18. The drive means includes an electric motor 20, a gear reducer 22 and a drive sprocket 24. A chain drive 26 interconnects drive sprocket 24 and driven sprockets 28.
The two-roller assembly 16 includes a pair of upright frames 30 and 32 appropriately secured by bolts 34 to base 10. A lower drive roller shaft 36 is journalled in bearings 38 and 40 mounted on frames 30 and 32. One end 36a of shaft 36 extends outwardly of frame 32 and has driven sprocket 28 drivingly mounted thereon. A portion of shaft 36 between the bearings is enlarged as at 36b and has a roughened periphery for drivingly engaging the interior periphery of a urethane rubber sleeve 38 that is tightly fitted thereonto. As typical dimensions only, the shaft portion 36b may be 2 /2 inches in diameter and the thickness of sleeve 38 may be 1% inches, so that the overall diameter of the lower roller is about 5 inches.
The upper roller of assembly 16 which is movable in a vertical plane toward and away from the lower roller includes an elongated non-rotating support shaft 40 whose ends are fixed in slide blocks 42 and 44 by means of set screws 43 and 45. The slide blocks 42 and 44 are arranged for vertical sliding in rectangular recesses formed in frames 30 and 32. -Mounted on support shaft 40 inwardly of frames 30 and 32 are bearings 46 and 48, and rotatably mounted on bearings 46 and 48 is an annular rigid work-engaging roller member 50. Again, as a typical dimension only, the outer diameter of roller 50 is 3 inches. As best seen in FIGS. 1 and 4, the axial length of roller 50 is greater than the axial length of urethane rubber sleeve 38, so that the ends of sleeve 38 are always spaced inwardly of the ends of roller member 50.
A pair of springs 52 and 54 are provided in frames 30 and 32 for normally resiliently biasing slide blocks 42 and 44 and roller 50 upwardly, so that normally roller 50 is spaced from the sleeve 38. The spacing of roller 50 from sleeve 38 is adjustable through threaded bolts 56 and 58 which are screwed into the frames 30 and 32 and which present tips that bear against blocks 42 and 44 for purposes of overcoming the bias of the springs 52 and 54 and for moving roller 50 toward sleeve 38. I am nuts 57 and 59 cooperate with frames 30 and 32 to lock the bolts 56 and 58 in selected positions. Appropriate plates 60 and 62 are secured to the exterior of frames 30 and 32 to retain and cover the bearings 38 and 40 and slide blocks 42 and 44.
Mounted on frames 30 and 32 to the feed side of the machine are brackets 64 and 66 which carry thereon, for bridging extension therebetween, a feed table, or support shelf 68. The shelf is provided on its upper surface with guide bars 70 for engaging edges of metal sheets that are to be fed to the rolling rollers. As shown, the guide bars are adjustable through clamp bolt 72 and slot 74 arrangements. The shelf has downwardly extending flanges 69 which are pivoted at 76 to brackets 64 and 66, and angular adjustment for shelf 68 is afforded by pressure clamp bolts 78 carried on flanges 69 cooperating with arcuate adjustment slots 80 in brackets 64 and 66.
In the operation of the machine, it will be understood that the lower roller is the driven roller and an appropriate control for the motor (not shown) may be provided including means for varying the rotational speed of the lower roller. The upper roller 50 is moved through bolts 56 and 58 toward engagement with sleeve 38, and a sheet of metal such as steel is fed to the bite of the rollers. The sleeve 38 takes the sheet 82 between the bite of the rollers, and roller 50 rotates on its mounting as the sheet 82 is taken through the roller bite. The pressure of roller 50 against sheet 82 and the corresponding deformation of the sleeve 38 acts to roll the sheet to a substantially continuous arcuate form with relatively no flats, the arcuate form extending over the entire length of the sheet. The tightest arcuate shape which sheet 82 could achieve would tend to approach the radius of curvature of roller 50. If the curvature attained in a sheet 82 is not sufficient, a greater curvature can be obtained by forcing roller 50 further against sleeve 38 within the permissible deformability limits of the urethane rubber.
It will be understood that machines constructed in accordance with the principles hereinabove depend upon the size of the rollers and the load bearing capacity of the urethane rubber roller to determine the maximum capacity of sheet metal that may be rolled. However, the machine as described hereinabove is capable of effecting rolling sheet steel in gauge sizes, up to 20 gauge (.0375 inch).
While there has been shown and described a particular embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention and, therefore, it is intended in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.
1. A two-roller machine for rolling, by utilization of only two rollers to roll into arcuate form, with virtually unnoticeable flats, sheet metal, such as steel, having thicknesses in the range of gauge sizes; said two-roller machine comprising, in combination: first roller means providing a sheet metal engaging periphery of urethane rubber; second roller means including a roller with a relatively rigid periphery; means for maintaining a fixed pre-selected spacing between the axes of said first and second roller means, so that said periphery of urethane rubber is caused to deform and acts to roll the sheet metal passing between said roller means to a desired final arcuate form with substantially uniform radius of curvature and with relatively no flats; drive means coupled to only said first roller means for selectively rotating said first roller means; and the hard periphery roller of the second roller means being caused to rotate by the relative movement of a metal sheet as it passes between said first and second roller means.
2. A device as set forth in claim 1 wherein said means for maintaining a fixed pre-selected spacing includes support means for supporting each roller means separately from the other roller means, means for selectively moving and adjusting the position of one of said roller means and its support means along a path extending radially of the other roller means, the locating of the axis of one of said roller means at a pre-selected spacing from the axis of the other of said roller means operating to provide a desired fixed amount of pressure between the rigid periphery of the second roller means and the urethane rubber periphery of the first roller means during the operation of rolling a metal sheet, a variation in spacing between the axes of the roller means providing for variation in such pressure so as to obtain selective curvatures of the metal sheet, and the selected pressure being dependent solely upon the selected spacing of the axes of the roller means and of the thickness of the metal sheet passing between the roller means for being formed.
3. A device as in claim 1 where the two-roller machine includes a pair of spaced frames, and said second roller means includes a support shaft supported on the spaced frames independently of the first roller means and bridging the space between the frames, and an annular roller rotatably mounted on said support shaft between said spaced frames.
4. A device as in claim 1 wherein the axis of one of the two roller means is located at a level above the axis of the other roller means, and the means for maintaining a fixed pre-selected spacing includes frame means for supporting each of the roller means independently of the other roller means, and so that the spacing between the axes of the roller means is independent of any of gravity forces, or the thickness of the sheet of metal passing between the roller means, or engagement or support between the roller means.
References Cited by the Examiner UNITED STATES PATENTS 2,397,608 4/ 1946 Johnson.
2,454,282 11/ 1948 Johnson.
2,662,573 12/ 1953 Cichoski et al.
2,719,562 10/1955 Beegle 72-166 2,815,779 12/ 1957 Higgins.
3,205,689 9/1965 Joseph.
RICHARD J. HERBST, Primary Examiner.
R. D. GREFE, Assistant Examiner.