US2319896A - Machine for cutting sheet material - Google Patents

Description

2 Sheets-Sheet 1 ..v a w\\ Q May 25, 1943.

E. E. WINKLEY MACHINE FOR CUTTING SHEET MATERIAL Filed Sept. 4, 1942 y 1943. E. E. WINKLEY 2,319,896

MACHINE FOR CUTTING SHEET MATERIAL Filed Sept. 4, 1942 2 Sheets-Sheet 2 Patented May 25, 1943 UNITED STATES PATENT OFFICE MACHINE FOR CUTTING SHEET MATERIAL Application September 4, 1942, Serial No. 457,365

8 Claims.

This invention relates to machines for operating upon sheet material, and is herein illustrated as embodied in a machine for cutting blanks, such as shoe part blanks from leather or fabric by the use of cutting dies.

It is an object of the present invention to provide an improved machine, for dieing out blanks, which is especially adapted to form blanks rapidly and economically with comparatively little expenditure of power and without excessive vibration.

To this end and as illustrated, the machine comprises two spaced rolls and a movable work support for presenting a piece of work with a die positioned thereon to the rolls, and to force the die through the work to produce a blank. Preferably and as shown, means is provided for separating the rolls upon the return movement of the die and work, to prevent a second operation upon the work which might tend to damage the same.

These and other features of the invention are disclosed in the-following specification and in the accompanying drawings, and are pointed out in the claims;

In the drawings,

Fig. 1 is a view in side elevation of a machine embodying one-form of the invention;

Fig. 2 is a view in end elevation of a portion of the machine shown in Fig. 1; and

Fig. 3 is a cross-sectional View, taken along line III--III of Fig, 2, showing the relation of the rolls to work being operated upon.

The invention contemplates the cutting of blanks from sheet material by the use of dies, in such manner that pressure is progressively applied along the cutting edge of a die positioned upon work. To this end, the machine comprises a lower pressure roll l and an upper pressure roll 12, which are normally spaced apart by a predetermined distance corresponding closely to the height of a particular die, such as die M, which is to produce a blank from sheet material Hi, there being an endless belt l8 having portions which extend at right angles to the axis of the roll 10 and at opposite sides of the roll forwardly and rearwardly of the machine from points closely adjacent to the upper face of the roll to form flat horizontal work receiving and supporting surfaces. The belt and the rolls are driven al ternately in opposite directions to advance the die and work past the rolls, and then to return the die and work to their original positions at one side of the roll.

The lower pressure roll in is carried by a shaft 20 mounted in suitable bearings 22 in the frame 24 of the machine.

The upper pressure roll I2 is carried by trunnions 26 mounted in blocks 28 slidably positioned in Vertical guideways 30 formed in a head casting 32. The blocks 28 are carried by links 34 and 36 connected by pins 38, the upper links 36 being pivoted at 40 on the upper portion of the head. The links 34 and 36 form toggles which are normally arranged to be held in straightened condition by links 42 under the action of pistons 44, but are arranged to be broken at a predetermined time by links 46 under action of pistons 48, both sets of pistons being fitted to slide in cylinders or bores 50 in the head 32. This arrangement is such that, when the toggles are straightened, the upper roll I2 is held in predetermined spaced position relatively to the lower roll ID, in order to effect a dieing-out operation as the die M and work It are advanced between the rolls. The toggles are arranged to be broken prior to a return movement of the belt, thus to raise the upper roll far enough so that it will exert no pressure upon the die and the work during the return movement of the belt,

In order to adjust the distance between the rolls in accordance with the height of various dies to be used in the machine, the head 32 which carries the upper roll I2 is mounted in the machine frame so that it may be adjusted to vary the position of the upper roll I2 relatively to the lower roll H] as desired. To this end, depending portions 52 of the head, in which the guideways 39 are formed, are arranged slidably to engage guideways 54 formed in brackets 56 secured to or formed integral with the frame 24. Opposite sides of the head 32 carry screw shafts 58, which are threaded into the upper portions of the brackets and which can be rotated by hand wheels 60 to adjust the height of the head, and consequently to vary the position of the upper roll relatively to the lower roll.

The endless belt l8 extends over two supporting rolls 62, located forwardly and rearwardly of the machine at opposite sides of the lower pressure roll l0 and each at some distance therefrom. The belt It extends from each roll 52 horizontally inward toward the roll l5 and at points adjacent to the upper surface of the lower pressure roll the belt passes over auxiliary supporting rolls 34 and thence downwardly over idler pulleys 66. Below the pulleys 66 and located substantially midway between them is an idler pulley 6B for maintaining the belt in spaced relation to the rolls 66.

The lower pressure roll is driven first in one direction and then in the opposite direction alternately, through an angular distance of about 180, by means of an oscillating segmental rack I (Fig. 1) which engages a pinion 12 carried by the pressure roll shaft 20. The lower pressure roll I0 also carries a gear I4, which is connected by a chain belt IE-to a sprocket I8 on the righthand supporting pulley 62, thus to drive the belt I8. The upper roll I2 is driven synchronously with the lower roll I0 by means of a gear 80 and intermediate gears 82, 84, 86 and 83, the lastmentioned gear being connected by a chain belt 90 to a gear 92 fast on the upper roll. Thegear ratios are so taken that the surface speeds of the belt I8 and the lower and upper pressure rolls I0 and I2 are the same, with the result that work presented to the machine at a point to the left of the pressure rolls, as shown in Fig. 1, will be advanced at uniform speed past the rolls and, upon reversal of direction of movement of the rack III, will return the Work to its original position.

The segmental rack I0 is preferably driven by hydraulic means. The rack-itself is carried upon a lever 04, pivoted on the frame at 96, the lever having an arm 08 carrying asegmental rack I00 in engagement'with a straight rack I62 carried by a piston Hi l-mounted in a hollow cylinder I06. The piston is reciprocated by a fluid under pressure, arrangedto enter the cylinder through one or the other of valveports I08 0r IIO, the fluid being supplied-by a pump IIZ through a connection-I I4 and a valve chamber II6. In the valve chamber is a piston I I8 having enlarged end portions forming valves I20 and I22, which, upon reciprocation of the piston I I8 by a valve rod I24, admit fluid under pressure, either to the port I08 or the'port H0, or, when in neutral position, closes-both the ports, in which case the fluid supplied through the connection I III will pass around the piston H3 and out through exhaust ports I26 and1I2'I.

The Valve rod is controlled by athree-arm lever I28 mounted upon a pivot I30, there being a latch I32 normally operative to engage one arm I34 of the lever I28 tohold the valve rod I24 in such position thatthe valve ports are closed. In the neutral position,.the lever I28 is urged about its pivot by a spring-pressed plunger I36, carried by a slide I38 mounted in a bracket I40 on the frame and'connected by arod I62 to the lever 94. The latch I32, is urged in a clockwise direction by a spring I44 and engages an abutment I46 on the arm I34 tohold the sam against rotation. In order to initiateoperation of the machine, the latch is arrangedtobe released by operation of a rod I48 under control of a hand lever I50 located at the front of themachine. Upon depression of .thevhand lever, thelatch I32 is rotated in a counterclockwise direction, releasing the arm I34 which, under the action of the plunger I36 upon an arm II of the lever I28, willrotate in a clockwisedirection, thus to force the piston I III to the left in Fig. 1, in which case the port I08 becomes an inlet port and the port I I0 becomes an outlet port. During this time the exhaust port I26 is closed and the exhaust port I2] is opened. Fluid passing through the port I03 will operate to move the piston I04 to the right and effect a counterclockwise movement of the segmental rack I0, with the result that the belt I8 and both pressure rolls will be moved toadvance the work and the die I4 in adirection from left to right between and past the pressure rolls. When the parts have moved through a suflicient distance to advance the die into a position rearwardly beyond the rolls, the rod IE2 and the slide I38 will have been moved to the left through a sufiicient distance to move a spring-pressed plunger I52, carried by the slide, into engagement with the arm I5I of the lever I28 and to swing the lever in a counterclockwise direction. As the lever I28 is swung thus itacts to move the piston II8 to th right, causing the port I08 to become an outlet port and the port [I0 to become an inlet port. At the same time the port I26 is opened and the port I21 is closed. This results in reversing the direction of movement of the piston I04 and the belt I8, and the pressure rolls are moved in the direction to move the work from right to left in Fig. 1, thereby to return it to its original position. When the machine is at rest, the piston is in neutral position with the valves closing both ports I08 and III), thus preventing flow of fluid in the system.

In order to ensure accuracy in the control of the opening and closing of the ports I 08 and I I0, the lever I28 is provided with an arm I54 having a projection I56 thereon which, when the machine is initially at rest, is arranged to engage an abutment I58 on the slide I36. When an operation of the machine is initiated, the lever I28 moves in a clockwise direction and the projection I56 will enter a U-shaped groove I60 to lock the lever I28 against rotation which would cause a change in the position of the valves. During movement of the slide I38 to the left, the projection I56 passes along the lower arm of the groove until it passes beyond the abutment I58. The plunger I52 then rotates the lever I28 in a clockwise direction, at which time the projection I56 will pass from the lower to the upper arm of the U and will then be again locked against rotation until the stroke is completed in the other direction.

As shown in Fig. 1, the toggle links 34, 36 are in nonparallel relation, with the result that the upper roll I2 is in its raised position, therefore inoperative to apply pressure to the Work. After the cycle of operation of the machine has commenced, fluid under pressure passing through connection I62 will force the pistons 44 to the right to effect a straightening of the toggle formed by the links, thereby to lower the pressure roll I2 into its operative position and maintain it there during movement of the die and work between the two rolls. Upon return movement of the die and work, when the valve port I08 is closed and the port H0 is opened, fluid pressure passing through the connection I64 will move the piston 50 to the left in Fig. 1, thereby breaking the toggle and-raising the upper roll I2 into inoperative position, So that it will not apply pressure to the die and Work, as the latter are returned to their original position.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. Ina machine for operating upon sheet material, a plurality of spaced pressure rolls, an endless belt for supporting thereon a piece of work and a die, means for moving the belt in a direction to advance the work and the die past the rolls to produce a cutting operation upon the work, means for subsequently moving the belt in a direction to move the work and the die past the rolls in a reverse direction, and means operative in timed relation to the movements of the belllt for raising or lowering one of the pressure re s.

, 2. In a machine for operating upon sheet material, a plurality of spaced pressure rolls, an endless belt having portions closely adjacent to one of the rolls for supporting a piece of work and a die adjacent to the rolls, means for moving the belt in directions successively to advance the work and die past the rolls to produce a cutting operation upon the work and to return the work and die to their original positions, and means operative in timed relation to the movements of the belt for effecting relative movement of the rolls into and out of pressure-applying relation to the work and die.

3. In a machine for operating upon sheet material, a plurality of spaced pressure rolls, a belt for feeding a piece of work and a die back and forth between the rolls, and power means for rotating the rolls and moving the belt.

4. In a machine for operating upon sheet material, a plurality of spaced pressure rolls, a belt for feeding a piece of work and a die back and forth between the rolls, and fluid-operated means for rotating the rolls and moving the belt.

5. In a machine for operating upon sheet material, a plurality of spaced pressure rolls, a belt for feeding a piece of work and a die back and forth between the rolls, power means for rotating the rolls and moving the belt, and automatic means for effecting relative movement of the rolls out of pressure-applying relation to the work and die upon return movement thereof.

6. A machine for operating upon sheet material comprising a pair of spaced rolls, an endless belt having portions located adjacent to the rolls for supporting a work piece and a die, means for rotating the rolls and moving the belt successively in directions to move the work and the die back and forth between the rolls, a control member for reversing the direction of movement of the rolls and the belt, and automatic means for operating the control member at the end of a cycle of movement of the belt.

7. In a machine for operating upon sheet material comprising a plurality of spaced pressure rolls, a work support having portions adjacent to the rolls on opposite sides thereof and comprising an endless belt, fluid pressure operated means for rotating the rolls and for moving the belt in a direction to advance it past the rolls, a work piece and a die positioned upon the belt, a control member for reversing the direction of movement of the rolls and belt, and automatic means for actuating the control member at the end of each advance movement of the work and die.

8. A machine for operating upon sheet material comprising a plurality of spaced pressure rolls, means for supporting a work piece and a die, fluid pressure operated means for rotating the rolls and for moving the work supporting means in directions to move the work piece and die back and forth between the rolls, and fluid pressure operated means for effecting relative movement of the rolls into and out of pressureapplying relation to the work piece and die in timed relation to rotation of the rolls.

ERASTUS E. WINKLEY.

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