US2454758A

US2454758A - Flexible cover forming machine

Info

Publication number: US2454758A
Application number: US608105A
Authority: US
Inventors: Jr Alfred Vischer
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-08-01
Filing date: 1945-08-01
Publication date: 1948-11-23
Anticipated expiration: 1965-11-23

Description

Nov. 23, 1948. A. vlscHER, JR

FLEXIBLE COVER FORMING MACHINE Filed Aug. 1, 1945 NOV. 23, 1948. A#VlsqgplER' JR v 2,454,758v

FLJIXIBLE` COVER FRMING MACHINE Filed Aug. l, 1945' 7 Sheets-Sheet 2 Nov. 23, 1948. A, VISCHER, JR f 2,454,758

FLEXIBLE covER FORMING MACHINE Filed Aug. 1, 1945 7 sheets-sheet 3 NOV. 23, 1948. A VlscHER, JR 2,454,758

FLEXIBLE COVER FORMING MACHINE Filed Aug. l, 1945 v 7 Sheets-Sheet 4 Nov. 23, 1948. A. vlscHER, JR

FLEXIBLE COVER FORMING MACHINE Filed Aug. l, 1 945 '7 sheets-sheet 5 Www] NOV. 23, 1948. A, VISCHER, JR

FLEXIBLE COVER FORMING MACHINE Filed Aug. 1, 1945 7 Sheets-Sheet 6 Nov. 23, 1948. A, WSC-HER, JR n 2,454,758 v FLEXIBLE covEE EORMING MACHINE 'Filed Aug. l, 1945 7 Sheets-Sheet '7 Patented Nov. 23, 1948 FLEXIBLE FORMING MACHINE Alfred Vischer, Jr., Park Ridge,v Ill., assgnor, by mesne assignments, of 4twelve-thirtieths to Alfred Vischer, Jr., two-thirtieths to William Vischer, two-thirtieths to Alfred Vischer, III, two-thirtieths to Alfred Vischer, Jr., as trustee, four-thirtieths to Walter W. Zitzewitz, fourthirtieths to Elmer K. Zitzewitz,`onethirtieth Ato Gertrude J. Zitzewitz, one-thirtieth to Barbara 0. Zitzewitz, and two-thirtieths to Gertrude V. Bouton ApplicationvAugust 1, 1945, Serial No. 608,105

s claims; (o1. 15s-54) My invention relates generally to flexible cover forming machines, and more particularly to' a machine for the quantity production of flexible covers of the type disclosedin'my `prior Patent No. 2,232,011. j

In themanufacture of the covers of pressure cookers of the type shown in the aforesaid patent, some difficulty has been encountered in forming the covers to render them flexible and to introduce the stresses necessaryto cause the cover to snap from its closed to open position, and vice versa. In the. past, such stresses were. introduced by securing the dished cover in the chuck of a lathe and applying theeiiing force. by means of rollers in the manner of a conventionalspinf ning operation. While such forming of the covers by a spinning process was practical for covers of smaller diameters, it was inadequate for covers of larger size. Even though the lathe was equipped with special tools and fixtures for applying the pressure through the rollers, it was found that the application of the torque to` the cover at its center tended, to distort the shape of the cover, and Was therefore not satisfactory, especially for covers of larger diameters. f

It is therefore an `object of the invention to provide an improved `machine for substantially automatically ,flexing covers of the type shown in said patent, to introduce the necessary stresses and flexibility. l Y.

A further object is to provide an improved cover flexing machine in which the torque is applied to the cover near the peripheral edge thereof.

Other objects will appear from the following description, reference being had to the accompanying drawings, in which: l,

Fig. 1 is a plan `View of the machine;

Fig. 2 is an end elevational view thereof Figs. 3 and 4 are transverse sectional views thereof, taken on the lines 3-3` and 4 4, respectively, of Fig. 1; y V

Figs. 5 and 6 are sectional ,viewsl of the gear drive, taken on the lines 5-5 and 6 6, respectively, of Fig. 7;

Fig. 7- is a. horizontal sectional view, ,tekenen l= 2 the plane of the main drive shaft, and showing particularly the means for operating the pressure hails;

Fig. Sis a horizontal sectional view showing the drive gearing;

Fig. 9 is a fragmentary sectional View showing the clutch tripping mechanism;

Figil) is a fragmentary sectional view, taken enfthe mi loq-m of Figi; and

Fig. 11n is a fragmentary sectional view, taken on the line Il-II of Fig. 2.

In general, `the purpose of the machine is to flexadished circular cover 2l) of the general shape shown in full lines in Fig. 3, to the shape shown in' dotted' lines in said figure, such lexure taking place While the cover is rotating, and thus by cold Working removing and imparting stresses to the -coverwhich will render it exible and cause it to snap from its Warped to its relatively nat shape, and vice versa, upon release and applicat'io'njof the requisite forces at its center and at least. two diametri'cally opposite points along its periphery.

` `The cover 2D is made of stainless steel, thus having :the necessary elasticity and strength t0 serve" asa cover for pressure cookers, in which the aggregate force applied may be in the order of '2000 pounds.` j' `The machine comprises a'frame 22 preferably oifc'ast iron,]having a bearing bracket 24 bolted thereto. The bracket 24 has a pair of bearings 26 fora shaft 28. A double V belt pulley 30 is adapted to be coupled to the shaft 28 by a suitable .clutch mechanism contained Within a housing 321` `This clutch mechanism includes a stop lug 34 which,`ivhen arrested by the end of a controlrod 36, declutches the pulley 3i) from the s'naftz's-.v p'

,'I'he. clutch control rod 35 is slidably mounted infapai'r of bearings `555 which are suitably mounted on the bearing portions 26 of the bracket 24. The -rodS has an operating knob Ml secured to one'.y endand is normally urged to the right (Fig. 2,), to cause-its end` to lie Within the path of the stopwll, byte coil spring a2, compressed between one of the bearing blocks 38 and a collar 44, the latter being suitably secured to the rod 36. The rod 36 also has a bushing 46 secured thereto, this bushing having a frusto conical latching portion 46 engageable in a notch 50 formed in a latch 52. The latch 52 is pivoted on a stud 54 and is biased to move counterclockwise (Fig. 2) by a tension spring 55.

The latch 62 has a sidewardly extending lug 58 adapted to be engaged by a clutch release arm 68 secured to the end of a shaft extension 62 on shaft |3l.

As shown most clearly in Fig. 8, the shaft 28 has frictional drag applied thereto by a clamp 64 having a suitable liner 66 of leather or the like. l'ihe clamp 64 is held from rotation by a projection 68 thereof, which fits in a slot 10 formed in an anchor plate 12, the latter being suitably secured to the bearing bracket 26. The degree of friction applied by the clamp 64 may be adjusted by means of a bolt 14. By virtue of the friction applied to the shaft 28 by the clamp 64, a small load is continuously placed on the shaft 28 to assure proper operation of the clutch mechanism contained in the housing 32.

The shaft 28 has a drive pinion 16 (Fig. 8) pinned thereto, this pinion meshing with a spur gear 18 pinned to a counter-shaft 80. The shaft 60 is mounted in suitable bushed bearings 82, and has a bevel pinion 84 pinned to the end thereof. The bevel pinion 84 meshes with a pair of bevel gears 86, 8l', the gear 81 being pinned to a shaft 80, while the hub of the bevel gear 86 interlocks with a sleeve 90 which is rotatably mounted on the shaft 88. The sleeve 90 forms part of a driving roller 9|, having an annulus 92 of suitable friction material, such as ber or compacted fabric, clamped thereto by a pair of rings 94, 95, the clamping being effected by hollow head cap screws 96 threaded in the clamping ring 95. The sleeve 90 is maintained in interlocking engagement with the bevel gear 86 by a collar 98 secured to the shaft 88.

As best shown in Fig. 1, a second driving roller 99 is provided by a sleeve member |00 pinned to the shaft 88 and having its frictionally driving annulus |02 clamped to the sleeve |00 by clamping rings |04, |05, the clamping pressure being applied by hollow head cap screws |06 threaded in the flange of the sleeve |00. From the foregoing, it will appear that the friction driving rollers 9| and 99 will be driven in opposite directions.

The cover 20 to be flexed has a central perforation which is engaged by a locating pin |08 (Fig. 3) guided for vertical movement in a bushing I0. The bushing I is secured in the upper end of a pedestal ||2 forming part of the frame 22, and the locating pin |08 is held in its uppermost position by a compressed coil spring I4. The pedestal ||2 also provides a central support for the main shaft 88, a suitable bearing bushing ||6 being secured in the pedestal ||2 by set screws I8. The upper end of the bushing l0 is chainfered to provide a bearing surface for the central portion of the cover 20.

The cover 20 is adapted to be clamped against the driving rollers 9|, 99, by a. pair of idler rollers |20, |2I, (Figs. 1 and 3). These idler rollers are mounted for free rotation upon a shaft |22, the ends of the shaft being eccentric and suitably journaled in bearings |24, |25. A handle |26 is secured to the shaft |22 so that when it is swung from the position in which it is shown in Fig. 3

Each of the balls |28, |29 has a gear segment |34 formed integrally therewith at each end, these segmental gears being in mesh as shown in Fig. 6; The bails are rocked upon their pivots by a link |36 (Figs. 3 and 4), the link being pivoted to the bail |28 lby an eccentric stud |38 which is locked in adjusted position by a set screw |40. The link |36 is held in position by a lug |4| secured to the bail 28. The other end ofthe link 36 has a large bore |42 (Fig. '1) to receive an eccentric |44, the link being held on the eccentric by a keeper plate |46. The eccentric |44 is formed' integrally with a sleeve |48 which extends through a suitable bearing opening in the frame 22, and has a plate splined thereto. An integral gear |52 is riveted to the plate |50. A similar internal gear |54 is secured to a fixed gear housing |56 and the latter is closed by a plate |58 which is secured to the frame 22.

In forming a cover, the dished disc is placed in the position indicated in full lines in Fig. 3, with the locating .pin |08 extending but a short distance through the perforation at the center of the cover. Diametrically opposite portions near the edge of the cover rest upon the driving rollers 9|, 99. The handle |26 is then swung to the position in which it is shown in Fig. 3, thereby, due to the eccentric mounting of the shaft |22, bringing the idler rollers |20, |2| into engagement with the cover and pressing the latter firmly against the driving rollers 9|, 99. The machine is then started by pulling on the knob 40 (Fig. 2) to remove the end portion of the rod 36 from engagement with the lug 34, thereby permitting the clutch lto operate and effect a driving connection between pulley 30 and the shaft 28. The rod 36 is latched in retracted position by the engagement of the conical portion 48 of the collar 46 in the notch 50 of latch 52. The main shaft 88 is thus driven through the pinion 16, spur gear 18, bevel pinion 84 (Fig. 8) and bevel gear 81. The driving roller 9| is driven inl a ydirection opposite to that of the shaft 88 aanwas through'the bevel gear 86. 'The cover, clamped against the-driving rollers 9|, 99, Ais thus rotated, and asit rotates the eccentric |44 (Fig. 7) isfrotated through the speed reducing gearing |52, |54, |60, at a speed 1&5@ of that of the `shaft 88. The bails |28, |29 are thus slowly swung from the positions in which they are shown in full lines in Fig. 3, successively to the positions in which they are shown in dotted lines'- The cover isY thereby flexed along successive diameters to the intermediate and fully warped shapes in which it is-shownin dotted-lines in Fig. 3, such flexure being accomplished by the engagement of the forming rollers |12 with the cover 2|) at substantially diametrically opposite points near the edge thereof. The flexure of the cover is continued as the bails |28, |29 return to their normal positions, as shown in full lines in Fig. 3.

As the bails approach their normal positions, the arm 6|] (secured to the end 62 of the shaft |3I, Fig. 9) engages the sidewardly extending lug 58 (Fig. 2) of the latch 52, swinging the latter clockwise and permitting the spring 42 to move the end of the rod 36 into position for engagement with the lug 34, thereby tripping the clutch within the housing 32 and stopping the machine. After swinging the handle |28 clockwise approximately 180 from the position in which it is shown in Fig. 3, to disengage the idler rollers |20, |2|, the cover may be removed from the machine, since now in its warped condition it easily clears the locating pin |08.

It has been found that covers flexed in this machine are uniformly worked to introduce stresses which give it the requisite properties to make it snap to its closed position when it is used, and to cause it to assume a normally warped shape. This makes it possible for the cover to be inserted in an inwardly flanged container having an opening of lesser diameter than that of the cover, as more fully disclosed in my aforesaid patent.

While I have shown and described a preferred embodiment of my invention, it will be apparent that numerous variations and modifications thereof may be made without departing from the underlying principles of the invention. I therefore desire, by the following claims, to include within the scope of the invention all such variations and modications by which substantially the results of my invention may be obtained through the use of substantially the same or equivalent means.

I claim:

1. In a machine of the class described, the combination of a pair of spaced driving rollers, means to press a disc against said rollers to secure frictional engagement therewith and thus to cause rotation of the disc, a drive shaft, a train of gearing connecting said drive shaft to said rollers to cause the latter to rotate in opposite directions, a pulley mounted on said drive shaft, a disengageable clutch connecting said pulley to the drive shaft, a manual control element, means for latching said element in a position to cause engagement of the clutch, a pair of forming rollers engageable with the upper surface of the disc at points near the periphery thereof and intermediate the points at which the driving roller engages the disc, means driven through said gearing for swinging said forming rollers downwardly and inwardly with respect to the center of the disc thereby to bend the disc into inverted trough shape successively along angularly incremental y diameters asfthe disc is rotated and thereafter t0 swing the forming rollers upwardly and outwardly, and a latch releasing member operated by lsaid last named means when the forming rollers have passed through a complete oscillatory cycle, thereby to release said manual control element and cause disengagement of said clutch.

2. In a machine of the classdescribed, a central vertically extending locating pin, a horizontal shaft beneath said locating pin, a driving roller fixed to said shaft, a second driving roller rotatable on said shaft, means for driving said rollers in oppositel directions a pair of balls mounted for pivotal movement and interconnected so as to swing in opposite directions, an eccentric for swinging said bails, a speed reducing gearing connecting said eccentric and said shaft, a roller mounted for free rotation on each of said bails, a pair of idler rollers for pressing a disc to be warped against said driving rollers, and means for moving said idler rollers toward said driving rollers to cause the idler rollers to press the disc against the driving rollers.

3. The combination set forth in claim 2, in which said speed reducing gearing for driving said eccentric comprises a fixed internal gear, a rotatable internal gear connected to the eccentric, said internal gears being of the same size but having different numbers of teeth, a pinion meshing with both of said internal gears, and an eccentric connected to said shaft and forming a bearing for said pinion whereby said pinion will roll around said internal gears and cause the movable internal gear to rotate through a small angle upon each revolution of the shaft.

4. In a machine of the class described, the combination of a pair of driving rollers, means for rotating said rollers at the same speed in opposite directions, idler rollers movable toward and away from said driving rollers for maintaining a cover to be formed in frictional contact with said driving rollers at diametrically opposite points of the cover, a pair of forming rollers engageable with a cover rotated by said driving rollers at substantially diametrically opposite points near the periphery of the cover and spaced intermediate the points at which the cover is engaged by the driving rollers, and means for swinging said forming rollers inwardly and downwardly with respect to the center of the cover, thereby to warp the cover into a generally troughlike shape along successive angularly incremental diameters as the cover is rotated by the driving rollers.

5. In a machine for warping flexible generally circular covers, the combination of means for gripping the cover at two diametrically opposite spaced points and rotating the cover about a central polar axis, a pair of elements engageable with the cover at substantially diametrically opposite points intermediate the points at which the cover is engaged by the gripping and rotating means, and means for swinging said elements downwardly and inwardly thereby to warp the cover into a generally inverted trough-like shape as it is rotated by the driving means.

6. In a machine for cold working generally circular flexible covers, the combination of means for frictionally engaging the cover at diametrically opposite points adjacent the edges thereof, said means being driven to rotate the cover about its center, a pair of elements engageable with said cover at points spaced substantially from the points at which said frictional means engage the cover, and means for slowly moving said ele- 7 ments downwardly and inwardly thereby to ex said cover successfully about angularly incremental diameters as the cover rotates.

ALFRED VISCHER, JR.

REFERENCES CITED The -following references are of record in the l111e of this patent:

Kollberg July 4, 1899 Number Number 8 Name Date Hjorth Aug. 9, 1904 Worth Sept. 19, 1911 Grin Apr. 16, 1918 Grotnes Oct. 26, 1926 Adams, Jr. May 6, 1930 Watkins Sept. 15, 1931 Cushwa et al. June 23, 1942 FOREIGN PATENTS Country Date Great Britain Mar. 17, 1920