US2096073A - Work holding device - Google Patents

Description

Oct. 19, 1937. c SPENCER 2,096,073

WORK HOLDING DEVICE Filed Nov. 23, 1955 3 Sheets-Sheet 1 FIG. I.

65 66 w w W 67 55 a I g8 36 HVVENTOR EC- SPENCER A T TORNE) Filed Nov. 23, 1935 3 Sheets-Sheet 2 FIG. 6'.

l I 77 I02 54 /NVENTOR I F. c. SPENCER 104 '/o9 RDfiB-W ATTORNEY Oct. 19, 1937.

F. C. SPENCER WORK HOLDING DEVICE 5 Sheets-Sheet 3 Filed NOV. 23, 1955 FIG. 9.

FIG. /0.

IN mm" F. c. SPENCER A TTORNE Y Patented Oct. 19, 1937 UNITED STATES WORK HOLDING DEVICE Frank 0. Spencer, VVestfield,-N. J., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application November 23, 1935, Serial No. 51,257

14 Claims.

This invention relates to work holding devices and more particularly to devices for holding,

measuring and positioning material or stock in strip or rod form to automatic material working machines, such for example as punch presses, automatic screw machines, and the like It may be desirable in such machines as punch presses to feed stock or material to the press in such a manner that successive applications of the working tools to the material will be made at successive accurately predetermined points or intervals on a strip of material being fed, and to hold the material securely but without damage thereto while being worked on.

One object of the invention is to provide a device for holdingstrip or rod or other elongated material firmly but without damage thereto.

Another object of the present invention is to provide apparatus for feeding strip, rod or other longitudinally extended material or stock automatically and intermittently or cyclically in step by step fashion, with ,accurate and dependable predetermination of successive positions of the material, the material being firmly held both while in motion between operations and while being operated on, and without damage thereto.

To these ends one embodiment of the invention presents the combination of a movable de- 30 vice for gripping a strip of material to be fed to a punch press and a fixed device for gripping the material while being punched, with a device actuated by the motion of the press to operate the two gripping devices, the two gripping devices or all three devices being fluid actuated, i. e. hydraulically or pneumatically operated and interconnected, the gripping devices comprising fluid pressed diaphragms to press the mate rial against an opposed solid member.

Other objects and features of the invention will appear from the following detailed description of an embodiment thereof in several modifications of a work holding and feeding device for a punch press constructed in accordance with 45 the invention, taken in connection with the accompanying drawings in which the same reference numerals are appended to identical parts in the several figures and in which Fig. 1 is a partly diagrammatic view in front elevation of a punch press having a material feeding device constructed in accordance with the invention;

Fig. 2 is an enlarged broken view of a control cam thereof taken on the line 22 of Fig. 1;

Fig. 3 is a section on the line 33 of Fig. 1;

Fig. 4 is a section on the line 44 of Fig. 1;

Fig. 5 is a section on the line 55 of Fig. 1;

Fig. 6 is a view like Fig. 1 of a modified form;

Fig. 7 is a section on the line l--'l of Fig. 6;

Fig. 8 is a view on the line 8-8 of Fig. 6;

Fig. 9 is a view like Fig. 1 of another modified form;

Fig. 10 is a diagrammatic dissected view of the control cams and fluid control pipes of Fig. 9;

Fig. 11 is a plan view enlarged of a modified form of diaphragm; 1

Fig. 1'2 isa section on the line l2-l2 of Fig. 11, and p Fig. 13 is a view similar to Fig. 3 of a modified form of gripping device.

In the embodiment disclosed in Figs. 1 to 5 inclusive, there is shown a punch press of any approved general construction and arrangement,

having a working bed in which a die, not shown, may be mounted in the customary fashion, and having a ram or reciprocatory head 2| in which a punch to coact with the die may be mounted. The head 2| may be driven by a connecting rod 22 from a crank 23, and a flywheel 24 is mounted on the shaft ll) of the crank 23, this shaft being driven in any approved mannerby means not shown.

The base 25 of the machine, on which the bed 20 is supported, and the bed 20 extend to the right as shown in Fig. 1, to support the material gripping and advancing means. A block 26 is rigidly mounted on or formed integral with the bed and has in its upper surface a trough-like groove or channel 21 (Fig. 3) oriented to point toward the axis of the punch and die of the machine, and adapted to receive and guide a strip 28 of material to be fed to the punch and die. A diaphragm 30 of suitably elastically flexible material such as thin sheet metal, which may also be corrugated if desired, is held in place across the top of the channel 21 by being firmly clamped between the block 26 and a cover-plate 3| held together by screws 29 as best shown in Fig. 3. I

The cover-plate 3| has a recess 32 in its under face, entirely closed below by the diaphragm 30 and laterally by the downwardly extending side walls of the cover-plate which are peripherally continuous around the recess; The roof of the recess formed by the cover-plate is also complete except for a passageway 33 extending through the cover-plate and through a nipple 34 integral with the cover-plate, which passageway 33 is for the admission of fluid to the recess 32 as hereinafter described.

A rail 3v is mounted on or formed integral with the bed 26 and is oriented toward the axis of the punch and die. A movable block 36 is mounted on the rail with freedom to slide therealong. The

- upper face of this block is formed with a channel 31 to receive the strip 26, like the channel 21, and which is closed by a diaphragm 46 clamped by screws 36 between the block 36 and a cover-plate 4| The cover-plate 4| is formed with a recess 42, passageway 43 and nipple 44 like the corresponding parts 32, 33, and 34 of the block 26.

A link 45 is pivotally attached to the block 36 by a pin 46 (Fig. 5) and to a pin mounted in one arm 41 of a bell crank lever pivotally mounted by a pin 56 on a rear vertical face of the bed 26 or base 25. The other arm of the bell crank lever is double comprising two arms or parts 46 and 49, the arms 41, 46, and .49 being integral or rigidly united in the relative positions shown in Fig. 1.

A lever 5| is also pivotally mounted on the pin 56 to be rotatable relatively to the bell crank lever and extends between the arms 46 and 49 thereof. A link or connecting rod 52 is connected at one end to the lever 5| and at'the other end to a crank 53 on the main crank-shaft l9 of the machine. v

The nipple 34 is connected by a pipe 54, through a T 55 (Fig. 2), to a nipple 56 formed on a coverplate 51 secured by screws 56 to a block 6| with a diaphragm 66 interposed between the block and cover-plate. The cover-plate 51 is formed with a recess 59 similar to the recess 32 in the cover-plate 3|, which recess 59 communicates through the bore 62 of the nipple 56 with the bore of the pipe 54 and so through the bore 33 with the recess 32.

The stem of the T 55 communicates with a chamber 63 in an accumulator body 64. The chamber 63 is closed except for the bore of the T stem and for a valve passage 65 in the roof of the chamber. A ball valve member 66 is held against the lower opening of the passage 65 by a compression spring 61 in the chamber 63. The passage 65 opens at its upper end into. a cylinder chamber 66 in the upper part of the body 64. A piston 69 in the cylinder is urged downwardly by a compression spring 16 within the cylinder.

In the block 6| is a recess I2 above and complementary to the recess 59 and separated therefrom only by the diaphragm 66. A plunger 13 housed in a suitable bore in the block 6| abuts at its lower end against the diaphragm 66 and is yieldingly urged up away from the diaphragm by a compression spring 14. A cam roller 15 is rotatably mounted in the upper end of the plunger and rolls on a cam 16 rigidly mounted on the main crank-shaft |9 of the machine.

.The nipple 44 is similarly connected by a flexible tube l6 and a pipe 11 through'a second T 18 with another nipple 19 formed on the block 6|. The T 16 and nipple l9 connect respectively with apparatus duplicating that just described as connected to the T 55 and nipple 56, including a cam roller 66 which rolls on a second cam 6| also rigidly mounted on the main crank-shaft l9 of the machine.

In describing the operation it should be kept in mind that the drawings are more or less'diagrammatic, and that the various parts are so proportioned and connected as to perform their several functions in the sequence and at the relative times described. In operation, a strip 26 of material to be operated on is fed through the channel 31 under the diaphragm 46 and entered intothe channel 21 under the diaphragm 36, the block 36 being then at the extreme right end Of its reciprocatory travel on the rail 35.

The machine is then started, i. e. the main crank-shaft I9 is set in rotation. At this time the press head 2| is at the bottom of its stroke and begins to rise withdrawing its punch from the die; above the top surface of the work strip 26, the cam 6| forces the roller 66 down and thus, in a manner explained in detail hereinafter, forces fluid under pressure into the recess 42 in the cover-plate 4|. This forces the diaphragm 46 down, clamping the strip 26 firmly and harmlessly between the diaphragm 46 and the floor of the channel 31. Meantime the crank 53 and connecting rod 52 are moving the lever 5| idly down.

from contact with the arm 49 to contact with the arm 46 while the above is taking place. The lever 5| then depresses the arm 46 drawing the block 36 to the left by means of the arm 41 and link 45. The block 36 having the strip 26 temporarily clamped thereto as described, draws the strip along from a supply thereof not shown at the right and pushes the left end of the strip along under the diaphragm 36 and between the punch and die. To permit this, there is at this time no pressure on the diaphragm 36.

When the block 36 has reached its extreme I left position, the crank 53 and rod 52 raise the lever 5| idly from contact with the arm 46 to contact with the arm 49. Meantime the cam 6| allows the roller 86 to rise releasing the pres-' sure on the diaphragm 46. 'At about the same time, the cam 16 forces the roller 15 and plunger 13 down against the tension of the spring 14. The plunger exerts downward pressure on the diaphragm 66 'and thus on a body of substantially incompressible fluid such as water, oil, mercury or the like which fills the recess 59, the bore of the pipe 54 and the recess 32, and which transmits the pressure to the diaphragm 36. Thus the diaphragm 36 is forced down and clamps the strip 26 firmly and harmlessly against the vfloor of the channel 21 in the stationary block 26.

Parenthetically, it is to be noted that the cam 6| and roller 66 actuate the diaphragm 46 by means and in a manner substantially similar to those just described for cam 16, roller I5 and diaphragm 36.

The strip 26 is thus firmly held by the block 26 while the punch descends to the bottom of its stroke. and returns the block 36 to its extreme right position. The above operations are then repeated in cyclic sequence until the machine is again stopped.

In many cases the diaphragms 36, 46, and 66 may be merely thin fiat septa as shown in Figs. 2, 3, and 4. In other instances it may be desirable toform one or more of them, as shown in Figs. 11 and 12, with a flat central pressure or contact portion 92 a fiat peripheral flange portion 93 to be clamped and an intermediate annularly corrugated portion 94 to provide increased 'flexibility and greater latitude of motion.

The accumulator structure disclosed in the housing 66 operates to keep the recess 59, T 56, pipe 54 and recess 32 full of fluid in case of minor leakages. This is a well known device whose mode of operation and structure willbe clear without further detailed description.

The cam 16 comprises a principal cam disk 62 rigidly keyed to the main crank-shaft I9 and an auxiliary disk 63 rotatably mounted on the crankshaft and clamped adjustably to the disk 62 by.

means of clamp screws 64 passing through an arcuate slot in the disk 63. .Thus the period of' As the punch clears the die and rises Meanwhile, the lever 5| lifts the arm 49 depression of the plunger 13 may be varied by adjusting the disk 83 on the disk 82. This also is a well known device which needs no further elucidation. The cam M has a similar structure.

The apparatus as above described comprises a closed hydraulic system to actuate and control the feeding of the strip 28. In Figs. 6, 7, and 8 there is disclosed a modified form of the apparatus having a pneumatic system in place of the hydraulic system above described, and also having a modified form of mechanical drive to reciprocate the block 36.

In this'*- arrangement, a cam 85 on the crankshaft I9 drives a cam rod 86 held against the ver is connected to the link 45 to drive the block 36 as in the preceding machine, the block 36 being thus drawn to the left by the cam 85 and returned to the right by the spring 95.

The pipe 54 is connected to an intake and exhaust valve housed in the block IOI. This comprises a poppet valve stem. and head I02 with a compression spring I03, which controls the inflow of compressed air through a pipe I04 leading from a compressed air supply not shown; and a combined actuator and exhaust valve member I05 resting on a compression spring I06 and adapted when depressed to close an exhaust port I01. The actuator I05 abuts against the cam 16 for actuation thereby. The pipe 11 leads to a duplicate intake and exhaust valve having an actuator I08 and a supply'line I09.

In operation, at the proper -moment of the cycle of events, the cam 16 depresses the member I05, which first closes the exhaust port I01 and then comes against and depresses the valve stem I02 thus allowing compressed air to pass from the supply line I04 into the pipe 54 andthence to the diaphragm 30 in the block 26. When the cam 16 releases the member I05, the poppet valve I02 closes and shuts off the supply of air, and then the member uncovers the port I01 allowing the air in the pipe 54 to exhaust therethrough and relieve the pressure on the diaphragm 30 in the block 26. In the same way the cam 8I and member I08 control the action of the diaphragm 40 in the block 36.

Figs. 9 and 10 disclose another modification of the apparatus in Which the reciprocation of the block 36 is hydraulically effected as well as the action of the clamping diaphragms. In this apparatus the general features are as before, the blocks 26 and 36 being substantially identically the same as in the preceding. Here however a hydraulic cylinder III is mounted at the right end of the track 35, and contains a piston II2 having a piston rod II3 connected at one end to the piston and at its other end to the block 36. Pipes H4 and H5 lead from the right and left ends of the cylinder respectively. A pressure pump H6 is mounted on the machine at a convenient point and may be driven as shown from the shaft I9, or. independently. The pump has a delivery or pressure line II1, an intake II8 drawing from a sump H9, and an overload relief line I20 delivering through a relief valve I2I into the sump.

The cam 16 drives the cam roller as before, but the cam roller is mounted on the stem I22 of a three port slide valve I23 of which the first port is connected to the pressure pipe II1, the middle port to the pipe 54 leading to the block 26, and the third port to a fluid return line I24. The cam 8| similarly actuates the stem I25 of. a three port slide valve I26 having its ports connected respectively to the lines H1, 11, and I24.

A third cam I21 also mounted on the shaft I9 I coacts with a cam roller I28 mounted on the valve stem I29 of a seven port slide valve I30 to actuate the valve. The first port of this valve is connected to the line I24, the second and third to the line II4, the fourth to the line II1, the fifth and sixth to the line H5 and the seventh to the line I24. 4

In operation, assume the block 36 to be in its extreme right position, and a strip to bein position, and the machine in action. At this. time the valve I26 connects the pressure line II1 to the supplyline 11 which transmits the pressure to the diaphragm 40 in the block 36 and so clamps the strip 28 in the block. The punch head 2| is now in its uppermost position. The I valve I30 then connects the pressure line II1 to the supply line H4 and, the return line 124 to the supply line I I5, thus causing the piston to drive the block 36 from its extreme right toits extreme left position carrying the strip 28 with it.

At this time also, the valve I23 has connected the supply line 54 to the return line I24, thereby relieving all pressure on the diaphragm in the block 26, so that the strip 28 may'slide freely thereunder.

A moment after the block 36 has come to rest in its extreme left position, the valve I23 disconnects the supply line 54 from the return line.

The valve I30 then disconnects the supply line II 4 from the pressure line H1 and connects it to the return line I24, while at the same time the valve disconnects the supply line II5 from the return line I24 and connects it to the pressure line I I I, thus causing the piston I I2 to drive the block 36 back to its extreme right position.

The above cycle of events will then be repeated so long as the machine is allowed to run.

The arrangement last described is thought of as using a substantiallyincompressible liquid as the pressure transmitting medium. However, if a supply of compressed air instead of the pump II6, be connected to the supply line I I1 and the return line I24, or the valve ports to which it is connected, be allowed to vent into the open atmosphere, the apparatus will function in substantially the same fashion.

In each case, if desired, a second diaphragm might be mounted opposite either of'the dla phragms 30 or 40 in place of the floor of the respective channels 21 or 31 if it be desirable to apply active pressure to both sides of the strip 28. Such an arrangement is shown in Fig. '13

which shows a modified form of the device shown in Fig. 3. Here a second diaphragm 'I3I is 4 a nipple 133 to the supply pipe 54, to which the nipple 34 is also connected.

,The embodiments of the invention herein disclosed are illustrative only and may be widely departed from and modified in many ways without departing from the spirit and scope of the invention as pointed out in and limited only by the appended claims.

What is claimed is:

1. In a material feeding apparatus the combination with a movable device for gripping material and a stationary device for gripping material, of a device to actuate the two gripping devices alternately to grip and release material, the two gripping devices being fluid actuated.

2. In a material feeding apparatus the combination with a movable device for gripping material and a stationary device for gripping material, of a device to actuate the two gripping devices alternately to grip and release material, the three devices being fluid actuated.

3. In a material feeding apparatus the combination with a movable device for gripping material and a stationary device for gripping material, of a device to actuate the two gripping devices alternately to grip and release material, the two gripping devices being fluid actuated, and each gripping device comprising a movable diaphragm and a member to coact therewith to grip material therebetween.

4. In a material feeding apparatus the combination with a movable device for gripping material and a stationary device for gripping material, of a device to actuate the two gripping devices alternately to grip and release material, the two gripping devices being fluid actuated, and each gripping device comprising a pair of movable diaphragms to grip material therebetween.

5.'In an apparatus for feeding material to an intermittently operating machine having a stationary material positioning means and a movable material positioning means, fluid actuated material gripping means on the stationary means, fluid actuated material gripping means on the movable means, means to move the movable means, and means actuated by the machine in accordance with the operationthereof to actuate the two fluid actuated gripping means andthe moving means.

6. In an apparatus for feeding material to an intermittently operating machine having a stationary material positioning means and a movable material positioning means, fluid actuated material gripping means on the stationary means, fluid actuated material gripping means on the movable means, fluid actuated means to move the movable means, and means actuated by the machine in accordance with the operation thereof to actuate the two fluid actuated gripping means and the fluid actuated moving means.

7. In an apparatus for feeding material to an intermittently operating machine having a stationary'material positioning means and a movable material positioning means, fluid actuated material gripping means on the stationary means, fluid actuated material gripping means on the movable means, means to move the. movable means, and means actuated by the machine in accordance with the operation thereof to actuate the two fluid actuated gripping means and the moving means, each of the fluid actuated gripping means comprising a movable diaphragm and a member to coact therewith to grip material therebetween.

8. In an apparatus for feeding material to an intermittently operating machine having a stationary material positioning means and a movable material positioning means, fluid actuated material gripping means on the stationary means, fluid actuated material gripping means on the movable means, fluid actuated means to move the movable means, and means actuated by the machine in accordance with the operation thereof to actuate the two fluid actuated gripping means i and the fluid actuated moving means, each of the fluid actuated gripping means comprising a movable diaphragm and a member to coact therewith to grip material therebetween.

10. In apparatus for feeding material to an intermittently operating machine having a stationary material positioning means and a movable material positioning means, fluid actuated material gripping means on the stationary means, fluid actuated material gripping means on the movable means, means to move the movable means, a source of fluid under pressure, and means actuated by the machine in accordance with the operation thereof to connect the two fluid actuated means to the source to actuate the same, each of the fluid actuated gripping means comprising a movable diaphragm and a member to coact therewith to grip material therebetween. 11.In apparatus for feeding material to an intermittently operating machine having'a stationary material positioning means and a movable material positioning means fluid actuated material gripping means on the stationary means, fluid actuated material gripping means on the movable means, fluid actuated means to move the movable means, a source of fluid under pressure, and means actuated by the machine in accordance with the operation thereof to connect the two fluid actuated means to the source to actuate the same, each of the fluid actuated gripping means comprising a pair of movable diaphragms to grip material therebetween.

12. An apparatus for intermittently feeding continuous material, the said apparatus comprising a stationary device for gripping material and including a diaphragm member directly actuable by fluid pressure to press directly on material to be gripped against a coacting member, a movable device for gripping material and including a diaphragm member directly actuable b-y fluid pressure to press directly on material to be gripped against a coacting member, and means to apply fluid pressure to the first and second named diaphragms in alternation for gripping and releasing material.

13. An apparatus for intermittently feeding continuous material, the said apparatus comprising a stationary device for gripping material and including a diaphragm member directly actuable byfluid pressure to press directly on material to be gripped against a coacting member, a reciprocable fluid actuated device for gripping material and including a diaphragm member directly actuable by fluid pressure to press directly on material to be gripped against a coacting member,

' and means to apply fluid pressure to the first and second named diaphragms in alternation for gripping and releasing material-and toapply fluid pressure to the reciprocable device to reciprocate the same.

14. In an apparatus having a continuously moving driving member and an intermittently operative material working tool, means to supply continuous material to the tool comprising a reciprocable device for gripping material and including a diaphragm member directly actuable by fluid pressure to press directly on material to be gripped against a coacting member, a stationary device for gripping material and including a diaphragm member directly actuable by fluid pressure to press directly on material to be gripped by the drivingmember to apply fluid pressure to the first and second named diaphragms in alternation for gripping and releasing material and to apply fluid pressure to the reciprocable device 10 to reciprocate the same.

FRANK C. SPENCER.

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