US1178168A - Guard for punch-presses. - Google Patents

Description

C. A. MACDONALD & M. P. DOUGHERTY.

GUARD FOR PUNCH PRESSES. APPLICATION FILED MAR. 9.19 14.

Patented Apr. 4,1916.

3 SHEETSSHEET I.

C. A. MACDONALD & M. P. DOUGHERTY.

' I GUARD FOR PUNCH PRESSES.

APPLICATION FILED MAR. 9" I914. Ll78fl68. Pmmmdmm4JMfi 3 SHEETS-SHEET 2.

C. A. MAcDONALD & M. P. DOUGHERTY. GUARD FOR PUNCH PRESSES;

APPLICATION FILED MAR. 9' 1914. 1,178,168,

Patented Apr. 4, 1916.

3 SHEETS-SHEET 3.

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CHARLES ADDISON MACDONALD AND MARTTN P. DOUGHERTY, OF ROCHESTER, NEW YORK.

GUARD FOR PUNCH-PRESSE S.

Specification of Letters Patent.

Application filed March 9, 1914. Serial No. 823,556.

To all whom it may concern:

Be it known that CHARLES ADDIS N MAC- DONALD and MARTIN P. DOUG ERTY, citi- Zens of the United States, residing at ROChStBI, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Guards for Punch-Presses, of which the following is a specification.

The object of this invention is to provide a guard for punch presses. This and other objects of the invention will. be illustrated in the drawings, described in the specification and pointed out in the claims at the end thereof.

In the accompanying drawings, Figure 1 is a front elevation of my improved guard in position on a punch press. Fig. 2 is a perspective view of the actuating cam for one of the guards. Fig. 3 is a side elevation of the guards in the frame of the press. Fig. at is a section taken on-the line i -1 of Fig. 3. Fig. '5 is a detail view of the ad justme'nt slide for the actuator. Fig. 6 is a perspective view of the actuator., Fig. 7 is a detail view of the bolt for holding together the parts shown in Figs. 5 and 6. Fig. 8 is a diagrammatic view of the lever of the punch press and the connections between it and one ofthe guards. Fig. 9 is an elevation of the top portion of an ordinary punch press. Fig. 10 is a section on the line 1010" of Fig. 9 looking to the left. Fig. 11 is a section on the line 1(l*'-10 of Fig. 9 looking to'the right. Fig. 12 is a section on the line 1'2 12' of Fig. 9. Fig. 13 shows details of the small parts of the clutch.

in the accompanying drawings like reference numerals indicate like parts.

in the drawings reference numeral 1 indicates the frame of the punch press having the two upright members 2 and 3 between which travels the ram t. The punch press is of the ordinary type having a shaft 67 at the top thereof. which shaft is provided with an eccentric or crank (l by which the ram l of the press is driven. .On this shaft (37 is mounted to run looselyia balance wheel =31 having a clutch 5 through which clutch said balance wheel drivesthe-shaft. This clutch S is connected by a link 0 to a lever 10 at the bottom of the machine nected the operating lever 13 pivoted at HQ At the short endof this lever is connected the link 15, the opposite end of which is connected to the short end 16 of the arm 16 pivoted on the stud 17 On the long arm of the lever 16 is mounted a guard plate 17, which is preferably of transparent material such as celluloid, but may be of metal or other material. The guard 17 is mounted so as to swing in frontof the die on the bed of the punch press, which would ordinarily be located near the bottom of the parts shown in Fig. 1 immediately behind the guard 17. These parts are so related that when the operator presses down the treadle 18 on the lever 10 it raises the link f) and moves the guard 17 from the left to the right to the position shown in Fig. 1. \Vhen the operator withdraws his foot so as to release the treadle 18. the link 9 is drawn down by the spring 19 which is attached to the lcv at one end and the frame of the machine at the other end and causes the guard 17 to move to the left to the position shown in Fig. 1.

If the operators hand is in contact with the die when the treadle is thrown, the parts heretofore described will operate to knock or push his hand and his arm out of the road and out of danger the speed with which the guard acts depending on the speed with which the treadle operates. If, however. the treadle is instantly released as soon as the clutch operates the guard 17 may not complete its movement or may be withdrawn before the ram descends to punch the meta l'. in which case there is still a possibility of the operators hand either not being re- .moved from danger or being allowed to getinto danger again before the ram has descended. Accidents may also happen due to other causes as will hereinafter be described. To'supplement the operation of the guard 17, and prevent danger to the hands of the operator during the movement of the ram and independently of the guard 17, the guard 20 is provided. This guard is carried on a lever 21 mounted on the same stud 17 Connected to this arm 21 is the link .22 carrying the stud 23 on which is mounted the anti-friction roller 24. This roller engages with the, cam 25 formed in the block 26, mounted upon a bridge 27,

which bridge is supported by the brackets 28 and 29, which brackets are attached to the frame of the press.

Mounted on the stud 23 is the anti-friction roller 30 which is engaged by the actuator 31, which actuator is carried by the ram of the press as follows; The adjustment slide 32 is attached to the ram of .the press by screws such as are shown in full and dotted lines in Fig. 4. The adjustment slide 32 is provided with a groove 36' in which engages the flange 37 on the actuator 31. T UU actuator 31 and the adjustment slide are clamped together by the clamping" bolt 38 which has a head 39 that engages with the slot 40 on the back of the adjustment slide 32. The adjustment slide is provided with a slot 41 and the actuator'is provided with a slot 42. The bolt 38extends through the slots 41 and 42 of the adjustment slide and the actuator and clamps them together and it is obvious that a considerable range .of

adjustment of the actuator 31 on the adjustment slide 32 is thereby permitted. The.

adjustment of the actuator 31- on the adjustment slide determines the travel of the lever 21 and guard 20.

The operation of the lever 21 and guard I 20 depends on the. operation of the ram of its the press and by setting the actuator .the 1 guard 20 can be given along travel or a short one. The time of the operation of the guard relative to the movement of the ram is determined by the shape of thecam 2%.

which cam is so shaped as to cause the, guar 2.0 to sweep in front of the die before theram has moved more than one third orone half of its stroke, thus causing the guard to push aside the hand of the operator before the punch can come into contacta-avi thfit.

As shown in Figs. 1 and 3, the .'.lever 16 is made up of two parts which are adjusted relatively to each other; and whichwill now be described.

The part 16 is provided with the up turned end 45 and the part 16*.isprovided with the upturned end 46. The upturned end 45 is slotted and the upturnedend 46 may be slotted or threaded, the two being clamped together by the bolts 47 so that the from the die.

that is in use on punch presses may be used in connection withmy invention. As there is a co5peration between the clutch and the guard, a particular form 'of clutch is illustrated in Figs. 9 to 13 inclusive, which clutch may be described as follows: The press isby the latch 63 which is normally pressed into engagement with the pin 60 by the spring 6-4.- The 'pin 60 is provided with the lug 65 with which the latch 63 can engage to hold it back. Mounted on the frame of the press is the latch 66 which is pressed toward the shaft 67 by the spring-68.- This latch carries at its outer end the segment 69 which bears against the periphery of the collar 70 keyed on the shaft 67. The collar 70 has a segmental recess 71 therein, at the rear side of which is a segmental piece made of-extra hard material to take the blow of the clutch delivered by the pin 60 on the wheel 61. The pin60 is also. made of extra hard material. The segment 69 is slightly eccentric on its outer surface and has the cam 72 on its inner surface (see Fig. 10). The latch 66 is operated from the treadle by the bell crank 73 mounted on the frame of the press. The clutch operates as follows: When the treadle 18 isdepremed the bell crank 73 is rockedand the latch 66 is, withdrawn. As the wheel 61' turns, the latch 63 carried thereby, .comes into contact with the outer surface of'the segment 69 and is moved outwardly thereby releasing the pin )50- which is pressed forward by the spring .62. into the recess 71, causing the shaft 67 to rotate with the wheel. When the treadle 18 is released the pin 66 and segment 69- move inward and the cam 65 on thepin 60 rides up on the cam'72 on the segment 69 until it is withdrawn from the recess 71, after'which it is held back by the latch 63. As long as the treadle18 is depressed the latch 66 will remain out. The ram of the press will operate and the guard 17 will .remain in the position shown in Fig. 1 and with each reciprocation of the ram the guard 20 swings forward and back. The position of the guard 17 .in Fig. 1 will be referred to as thesafety position while the position of the guard 20 will be referred to as the danger position.- he operators hand is normally placed b'e ween the punch and die in feeding the press and this will be referred to as the danger position. The guard sweeps the hand horizontally 6r laterally to the right to the so called safety position. A

strip of rubber or the other soft material 75 may be put at the forward edge of each of the guards to cushion the blow that thev the fly wheel 61 which rotates continuously power is transmitted from this wheel to the crank shaft 67 by the clutch. The clutch will remain closed and drive the crank shaft as long as the treadle 18 is held down. In the ordinary, operation of the press the operator first puts a blank on the die in the press and then presses the treadle down-with his foot to start the press and then lifts his foot to permit the treadle to rise again at once,'so that the ram of the press will make a single complete stroke and then stop, permitting his hand to be safely placed above the die to remove the finished piece and insert a fresh blank. The rain will regularly stop because the springs in the clutch will act to open the clutch and disconnect the crank shaft from the iiy wheel. If, however, one or the other of these springs break the clutch will remain closed regardless of the position of the treadle and the ram will keep on operating until the belt of the press is thrown. In such case the ram is apt to catch the hand of the operator on its next downward stroke which is unexpected by the operator because he expects the clutch to open and stop theram at the top of its stroke. He,

;, therefore, puts his hand into the press;

above the die to change the stock without any thought of danger. As the ram de-. sceuds at once it will catch hishand before he can think to remove it. The press may not operate this way more than once in several hundred thousand or even several million times and its action when it does come is therefore the more unexpected and the more dangerous on that account. During the second and subsequent movements of the ram due to the broken clutch the trcadle will be in normal position holding the guard 17 in idle pqosition or danger position. It will tl'ierefore be seen that in such r'ncrgencies the guard 17 is useless because it is driven by the treadle which remains idle. "if the guard is driven by the ram instead of the treadle the breaking of the spring in the clutch will no longer affect the operation of the guard because the guard and rain will erate together and the guard will knock the hand out of danger each time as the ram descends and before it gets down far enough to catch the hand. When the guard is driven by the ram it will move rapidly and will strike the hani or arm a y heavy blow. This is due to the fact that the 17am moves very fast and the guard must move very much faster still if it is to reach the hand and throw it out from the diebefore the ram closes in on the die. If these blows are repeated very often the hand or the arm of the o erator will be severely bruised. It is therefbre objectionable to depend primarily on the guard driven by the ram to protect the operators hand. The guard operated by the treadle will push the hand out of danger more gently especially as the speed of its movement is largely within the control of the operator. Therefore the guard moved by the treadle must be primarily depended on to protect the operator in the ordinary operation of the press and as. this will not protect the operator under such abnormal conditions as above described, the guard operated by the ram must also be used to give complete protection to the operator.

I claim:

1. In a guard for a punch press, the combination of a punch press frame, a plurality of guards pivotally supported from said frame, a ram reciprocating in said punch press, means for driving said ram and means for'controlling the operation of said driving means, one of said guards being operated to safety position by said controlling means and the other of said guards being operated to safety position in sequence therewith by the operation of said driving means.

2. In a punch press the combination of an upright frame and a bed, a ram working toward and away from said bed, a bridge mounted on said frame, a lever pivotally said lever, a stud mounted on said link, a

cam mounted on the bridge with which one end of said studengages, an actuator mounted on the ram with which the other end of said stud engages, said stud being adapted to move up and down with the ram and sidewise according to the pitch of the cam causing the lever to swing accordingly.

3. In a punch press the combination of a frame, a ram mounted to reciprocate in said frame, an adjustment slide fastened to said ram, an actuator adjustably mounted on said slide, a cam mounted on said frame opposite said actuator, a stud engaging with both said actuator and said cam and adapted to be moved vertically and laterally thereby on the reciprocation of said ram.

4. In a punch press the combination of a. frame, a ram mounted to reciprocate in said frame, an adjustment slide fastened to said ram, an actuator adjustably mounted on said slide, a cam mounted on said frame opposite said actuator, a stud engaging with both said actuator and said cam and adapted to be moved vertically and laterally thereby on the reciprocation of said ram, a lever and a connection between said stud and said lever whercbv the lever is oscillated on the reciprocation of said ram.

mounted on said bridge, a link connected to Y both said uance ed to be moved vertically and laterally said lever whereby .the reciprocation of said cillate thereon,

thereby on the reciprocation of said ram, a lever and a connection between said stud and the lever is oscillated on ram, said actuator being adjustable to vary the length of the stroke of the lever or its time-of operation with reference to theoperation of the ram.

6. In a guard for a punch press the combination of a' frame, a lever mountedto ostwo sections, each 0 said sections having an upturned end, said sections being clamped aid upturned ends, one

together through of said sections b on the other ends.

ing adjustable laterally press head and dies, of

press to move transversely across the front of the press dies, said device being normally positioned at a. distance to one side" of the vertical center of the front of the press dies and an actuating connection between said device and the press head for positively oscillating the device across said vertical center of the front of the dies at Copies a ram mounted to reciprocate in said ated press having a nation of crank saidlever being made up "of thereby and a frame therefor,

section through saidupturned v side of the operators arms and 7. The combination with a power-oper -ated ress having a a sa ety device pivotally mounted on the each stroke of the press; substantially as described. 7

8. The combination with a power opera guard member pivoted to swing transversely across the front of the press dies, and an actuating. connection between said member and a part'of the press which moves with each stroke of the press for positively oscillating both directions across the face of the press, said guard member and its. actuating consaid guard member in press head and dies, of

nection being normally positioned at a distance laterally from the vertical centerof the front of the press dies, substantially as described.

9. In a guard for a punchipre'ss the combishaft and a' ram driven a. vertically disposed gate mounted on sald frame, connections between said gate and said xcrank shaft whereby said gate is caused "tomove across in front of said ram and from one thereto whereby the operators be pushed away from said ram,.as thcshaft operates to push the ram down.

In testimony whereof we affix our'signaof this patent may be obtained for five cents each, by addressing th'e Commissioner or latents,

Washington, D 43."

transversely hands will

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