US1525645A - Press guard - Google Patents

Description

F. A. FULLER PRESS GUARD F b, 10. 7192s. 1,525.64;

Filed Aug. 25. 1923 Sheets-Sheet 1 INVENTOR ATTORNEY Feb. 10. 1925.

F. A. FULLER PRESS GUARD Filed Aug. 25. 1923 2 Sheets-Sheet 2 N Q 9 Q um Iii; Iv

ATTORNEY I YENTQR lichdfw BY together with others, such as convenience in.

Patented Feb. 10, i925.

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FRANZ A, FULLER, 0F NEWARK, NEW JERSEY.

ERESS GUARD.

Application filed August 25, 1923. Serial No. 659,281.

To all whom it may concern:

Be it known that I, FRANZ A. FULLER, a citizen of the United States, residing at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in. Press Guards, of which the following is a specificat on.

This invention relates to safety devices as applied to treadle Controlled machinery and particularly to such types as power actuated punch presses.

One of the objects of the invention is to provide a barrier or guard with means whereby it is interposed between the operator and danger zone ofthe press, imme diately prior to the descent of the ram or plunger to make contact with the work part disposed on the die or fixedportion of the press.

A further purpose is to produce means which prevent operation of the press until the guard has completed contact with the platen of the press, irrespective of treadle movement, thus avoiding premature action of the press likely to damage any intervening obiect between the guard and platen.

Another aim is in the provision of means to prevent the untimely descent of the guard and hence action of the press.

' These several aims, objects and purposes,

application, adjustability and efficiency, are attained by the novel construction, combination and arrangement of parts hereafter described and shown in the accompanying drawings, forming a material part of this disclosure, and in which Figure 1, is a front elevational view of a conventional type of power punch press,

showingthe application of an embodiment of the invention.

Figure 2 is a side View of the same. ,lligure 3 isa perspective view showing the main operative parts of the invention in detail.

Figure 4 is an enlarged transverse sectional view take-non line of Fig. 3.

Figure 5 is a fragmentary side view of the guard latch operating means.

Figure 6 is an enlarged sectional View taken .on line 6-6 of Figure 1.

An inclined type of punch press is illustrated in the, drawing, the same being composed ofa body 15, itsourved base being adjustably, mounted on legs 16 and having of the fork another bearings 17 in its upper portion for the shaft 18.

Thlsshaft extends outward at one end to accommodate a clutch, generally designated by the numeral 19, and beyond the.

reciprocative motion to the ram or plunger 22, slidable in guides 23 at the frontof the press, to which a punch 24 may beattached and on the bed 25 is a bolster 26 to which is clamped the die block 27 carrying a die 28.

The press is put in operation by depressing a treadle or foot lever 29, normally held in a raised positionby the tension spring 30, movement of the treadle being communicatcd to the clutch 19 by a rod .31. which may be adjusted in operativelength by a turnbuckle 32.

The foregoing is generally descriptiveof any common type of single acting, power operated press and given only to illustrate the application of the invention, the dis closure of which follows.

In place of the rod 31 directly connecting with the, clutch device, an arm 33 is pivoted at the rear of the press, at 34, to extend towards the front at either side of the press and to this arm the upper end of the rod 31 is connected and an additional rod 351s used to connect the arm w th the Clutch.

Fixed on the forward end of the arm 33 containing slots 37 and at a point rearward pa1r of plates 38 are fixed on the arm. these plates carrying a pivot 39 on which a forwardly extending lever 40 is mounted.

The lever is guided between the plates 36 and has fixed in it a pin 41 operable in the slots 37 limiting the relative motion of the lever and arm and in addition to the weight of thelever, a spring 42 is interposed between the arm and lever tending to press the latter element forcibly downward.

The outer end of the lever is bent to extend, as at40', in front of the press and has engaged with it an adjustable bar 43 held by clamp screws, this bar extending substantially horizontal in front of the plunger 22.

Attached near the end of the ,bar 43 is a flat upright stem 44, slotted for vertical adjustment and provided with means for clamping to the bar, this stem being integral with a guard plate 45 extending across the front of the plunger at its lower end and movable by action of the treadle to make contact with the bolster or press bed as shown by the broken lines in Figure 2.

It is to be noted that a full and complete movement of the guard must take place before the clutch rod 35 can be moved to engage the clutch, due to the pin 4L1 making Contact with the upper end of the slot 37, thus preventing it from transmitting suiiicient movement of the arm 33, in case of some object being interposed between the lower edge of the guard plate 4-5 and the bolster 26, when the parts are properly adjusted.

The guard plate 45 is shown as apertured to permit a view of the work when in its lowered. position and is suiiiciently rigid to effectively prevent dislocation by the hands of an operator.

It is also apparent that if the hands he so placed as to be struck by the guard descending by pressure applied to the treadle, the

blow will be cushioned by the spring 42, permitting withdrawal without serious damage being done and that the plunger cannot descend until after such removal of the hands or other objects which may be inadvertently interposed.

In order to maintain the guard in a lowered position and thus assure a reciprocative movement of the plunger, even if the treadle should be released prematurely or before the clutch elements have made operative engagement, the device shown in Figs. 1, 5 and 6 is used.

This device consists of a horizontal bracket 4-6 rigidly fixed to one of the press plunger guides 23, on the side adjacent the arm and lever, near its lower end, the bracket having a longitudinal slot 47 suited to receive and guide a slide L8 provided with a bevelled outwardly extending end 49 and containing a recess 50, the rear wall 51 of which is also correspondingly bevelled.

Access is had to the recess 50 through an opening 52 in the outer wall of the bracket 46. this wall also containing a slot 53 through which extends a pin 54, fixed in the slide 48, to which one end of a tension spring 59 is attached, its outer end being engaged with a pin 60 lined in the bracket and adapted to draw the slide outwardly.

The latch-like bevelled end 49 of the slide is thus normally held in the path of the arm 33, said arm at its free end being provided with an outwardly extending projection 33' designed to engage with the latch-like bevelled end 49 of the slide when the arm 33 moves downwardly, thereby pressing the slide back into the bracket, until the arm has fully passed, whereupon the spring 59 draws the slide out, thus preventing the return of the arm.

The slide however is retracted by the bevelled end (31 of an arm 62, rigidly held on the side of the plunger 22, this arm entering the recess 50 and making contact with the element 51, moving the slide 48 back and holding it there. clearing the path of the projection 33 of the arm 33 until the plunger has made its stroke and is beginning to rise to its normal position.

Thus it will be seen that the guard 45 cannot rise prematurely but will remain in downward operative position until the plunger has fully completed its downward stroke and is beginning to rise to its normal upper position, assuring safety to the operator irrespective of treadle action made inter veningly.

From the foregoing it will be seen that a simple device for this purpose has been disclosed in the preferred form of its embodiment. but it is not desired to restrict the details to the exact construction shown. it being obvious that changes, not involving the exercise of invention, may be made without conflicting with the scope of the appended claims.

Having thus described my invention. what I claim as new and desire to secure by Letters Patent, is

1. In a device of the class described, the combination with a punch press having a frame, a bed, a power driven clutch actuated crank shaft, a plunger operated thereby and a pedal controlling said clutch, of an arm pivoted on said frame, a rod directly connected between said arm and pedal, said arm being operatively engaged with said clutch, a lever pivoted on the arm, means for limiting the relative movement of said arm and lever, saidlever having its front end bent to extend in front of said plunger, and a depending guard adjustably secured to said lever.

2. In a device of the class described, the combination with a power punch press, of a guard disposed in front of the plunger, a bar to which the stem element of said guard is adiustably attached, a lever bent to adjustably support said bar, an arm pivoted to the frame of the press, said lever being pivoted on said arm, pedal means for actuat ing said arm, means for preventing the press from operating prior to the full descent of said guard, a latch on the side of said press, said latch preventing the rise of said arm, and means carried by the plunger of said press for releasing said latch.

3. In a device of the class described, the combination with a punch press having a frame, a bed, a power driven clutch actuated crank shaft, a plunger operated thereby and a pedal controlling said clutch, of an arm pivoted on said frame, a rod directly connected between said arm and pedal, said arm being operatively engaged with said clutch, a lever pivoted on the arm, means for limiting the relative movement of said arm and lever, said. lever having its front end bent to extend in front of said plunger, and a guard adjustably carried on said lever, said guard being adapted to make contact with the bed of the press prior to permitting full movement of said arm.

4. In a device of the class described, the combination with a punch press having a frame, a bed, a power driven clutch actuated c 'ank shaft, a plunger operated thereby and a pedal controlling said clutch, of an arm pivoted on said frame, a rod directly connected between said arm and pedal, said arm being operatively engaged with said clutch, a lever pivoted on the arm, a forked guide at the outer end of the arm in which the lever operates, said guide being slotted, a spring in the guide tending to press said lever downward, said'lever being bent to extend in front of said plunger, a depending guard plate adjustably attached to the bent end of said lever, and a pin in said lever operative in the slot of said guide, preventing completion of movement of said arm until said plate has reached the lowest point permissible by said bed.

5. In a device of the class described, the combination with a punch press having a frame, a bed, a power driven clutch actuated crank shaft, a plunger operated thereby and a pedal controlling said clutch, of an arm pivoted on said frame, a rod directly connected between said arm and pedal, said arm being operatively engaged with said clutch, alever pivoted on the arm, means for limiting the relative movement of said arm and lever, said lever having its front end bent to extend in front of said plunger, a guard adjustably carried on said lever, said guard being adapted to swing into contact with the bed of the press prior to the completion of full movement of said arm, a spring actuated sliding latch on the frame of the press normally intercepting the upward movement of said arm, and means carried by said plunger for removing said latch from the path of said arm when said plunger is beginning to rise to its upper position.

This specification signed and witnessed this 24th day of August, 1923.

FRANZ A. FULLER. lVitnesses A. B. UNDERHILL, PAUL E. HARTMAN.

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