US2257087A - Perforating machine - Google Patents

Description

pt. 30, 19 H. BOOTHROYD 2,257,087

PERFORATING MACHINE Filed Jan. 25, ,1940

Fig'l.

zze i \\42 Patented Sept. 30, 1941 UNITED STATES PATENT OFFICE PERFORATING MACHINE Hubert Boothroyd, Leicester, England, assignor to United Shoe Machinery Corporation, Borough of Flemington, N. J., a corporation of New Jersey Application January 25, 1940, Serial No. 315,505 In Great Britain February 1'7, 1939 3 Claims.

commonly used for cutting ornamental openingsin shoe parts comprises a reciprocating plunger carrying a die arranged to be moved toward and away from a work support in performing cutting operations upon blanks positioned upon the support. The machine is usually arranged so that various dies of different shapes or sizes can be secured to the plunger. One difficulty that has been experienced in connection with this machine is that, since the heights of the dies may vary considerably, the stroke of the plunger must be adjusted to compensate for the variation in the heights of the dies used, and if the adjustment is not properly made there is some likelihood of breaking a die or otherwise damaging the machine. Accordingly, it is an object of the invention to provide an improved perforating machine of the type referred to, in which the difficulty aforementioned will be obviated.

To this end and as illustrated, I have provided a perforating machine in which there is a plunger movable heightwise of the work support and having a die releasably secured thereto,. power means for driving the plunger and a wedge forming part of the plunger for varying the physical length of the plunger, together with means for securing the die to the plunger which can be operated in attaching a die to or releasing a die from the plunger only when the wedge is adjusted to render the length of the plunger to correspond to that required for a die of maximum height to be used in the machine. This construction is advantageous in that it eliminates any likelihood of breakage of dies or other machine parts caused by securing to the plunger a die of greater height than that for which the plunger is adjusted.

These and other features of the invention are disclosed in the following specification and accompanying drawing and are pointed out in the claims.

In the drawing:

Fig. 1 is a view in side elevation, partly in section, of a cut-out machine embodying my invention;

Fig. 2 is a front View of the upper portion of the machine;

Fig. 3 is a sectinonal view taken along line III-1110f Fig. 1; and

Fig. 4 is a sectional view taken along line IVIV of Fig. 1.

The illustrative machine comprises a C-shaped frame It! carrying a work sup-port l2 and a cutting die I4 movable heightwise of the frame toward and away from the work support in producing cutting operations upon sheet material, such as a shoe upper blank positioned upon the support. The die I4 is secured to the lower end of a plunger l6, which is slidably mounted in the frame and arranged to be moved downwardly by a block l8 pivotally mounted upon the end of a bell crank lever 21. carried by a shaft 22 and arranged to be oscillated by a link 24 driven by an eccentric 26 upon a drive shaft 28, the drive shaft being arranged to be connected by means of a clutch 32 to a pulley 30 (Fig. 4). A spring 34 extending between the block l8 and the plunger I6 is operable normally to maintain the plunger in engagement with the lower surface of the block.

The die i4 is arranged for a preliminary movement toward the work support l2 prior to each operation of the machine, in order to facilitate accurate positioning of the work relatively to the die. To this end, the plunger i6 is provided with a pin 36, which extends through an'elongated slot 38 in the frame. The pin 36 is connected to one end of a lever 50 mounted on a pivot 42, there being a treadle rod 44 for operating the lever in such manner as to cause the plunger to move the die downwardly toward the work support against the resistance of the spring, 34.

Mechanism is provided for adjusting the effective length of the plunger [6 in order to adopt the machinefor use in connection with dies of different heights. In View of this, the upper end of the plunger !6 comprises a wedge member 48 positioned in a groove 45, the upper surface of the wedge being normally maintained in engagement with the block l8 by the spring 34. The under face of the wedge member 48 is inclineddownwardly toward its forward end and rests upon a similarly sloping face forming the bottom of the groove 46. The wedge member 48 is adjusted by a threaded stem 5d passing rearwardly through a downturned lug 52 at the forward end of the wedge member and is threaded into a hole in the plunger l6. The.

stem 50 is secured against endwise movement receive the flanges I6.

relatively to the wedge member 48 by means of a transverse pin 54 in the lug 52 and extending across a circumferential groove 58 in the stem. The stem 58 carries a hand nut 58, positioned on its forward end by which the wedge member 48 can be moved transversely of the plunger I 5 to cause its upper face to be positioned at various elevations above the upper end of the plunger. A spring pressed plunger 60, carried by the wedge member 48, bears against the rear face of the nut 58 to maintain the wedge in adjusted'position.

To facilitate the assembly of dies of different sizes in the machine, each die is secured to a base plate 62 having a pair or split studs64' '(Fig. 3) extending from it and spaced apart. laterally. The studs 64 fit tightly within verti cal sockets 66 formed in the lower end of the plunger I 6 and are held in position by a projecting stem 58 slidably positioned in the plunger and extending across grooves I in the studs. Just forwardly of that portion which engages the studs, the stem 68 is reduced in diameter, as shown at I2, in Fig. 1, to a size which; is less than the distance between the studs. Thus, by

pushing the stem 68 rearwardly against the action of a spring "I4 behind it, the reduced portionof'the stem can be brought .opposite to the studs, which will enable the die to be removed from its block.

It will be'understood that, if the upper face of thewedge member 48 has been adjusted to extend well above the upper end of the plunger I 6, as would be necessary to ensure that a cornparatively low die is driven completely through the work when the block I8 strikes against the wedge membenand if, then, a relatively high die were attached to the plunger I8 by mistake, there been adjusted to a position suitable for the attachment of a die of the greatest height which it is expected to use, the operator thereafter readjusting the wedge member in accordance with f the height of thedie if the die is of less than the maximum height. To accomplish this,

'meansfisprovided for preventing the stem 68 from being urged rearwardly until the wedge member 48 has been adjusted to its lowermost position relatively to the plunger I6. Accordingly, the upper face of the wedge member'48 is provided 'at its opposite sides with narrow, outwardly extending flanges '16,

against the forward face 8!) of the machine frame. The plate I8 has an opening in it through which the wedge member 48' extends and has outwardly extending notches formed at opposite sides of the upper end of the opening to plate." By reason of the engagement between the wedgemember iii and the plate 1B, any height- ,{Wise adjustment in the position of the wedge member imparts a similar'heightwise movementwhich are arranged to engage a" vertical plateIB lying The plate I8 is loosely I} 'held in position against the face 88 by studs 82 passing through vertical elongated slots 8 inthe When the wedge member 48 is so adjusted as to set the machine for use of dies of the maximum height, it will be adjusted outwardly to its greatest extent, so as to shorten the over-all length 5 of the plunger I8 and the die, and in this position of the wedge member the plate I8 will occupy its lowermost position relatively to the plunger I6.

In order to prevent a die from being removed 10 from the plunger I6 and another substituted for it, except at such time as the wedge member 48 is in the position just mentioned, the plate I8 is extended downwardly by a sufficient distance so as to pass below the die-retaining stem, 68. The plate 18 is provided with a relatively short vertical keyhole slot 86, through which the stem 58 passes when the plate is in its lowermost position. The opposite sides of that part of the ,stem 68 lying adjacent to the slot 86 are slabbed 20 off at 81 for a distance slightly greater than the thickness of the plate in order to provide the necessary clearance for the stem to lie Within the slot. When thewedge member 48 occupies any adjusted position differing from its most for ward position, the plate member occupies a position relatively to the stem 68 so that the latter passes through the narrow portion of the slot;'

In that position, the shoulder 89 formed on the stem will prevent the stem from being positioned rearwardly far enough .to allow the. die to be detached from the plunger I6. However, when the stem 48 is adjusted to its most forward posi-r 40; 90, which is arranged to be moved endwise by a spring 92 (Fig. 4) to cause thebolt to enter a hole in'the driving pulley 38, thus to couple the pulley and shaft together for rotation in unison. When, the machine is at rest, the clutch bolt 90 is held withdrawn from engagement with the driving pulley by a wedge block 94 secured to a depending arm-96 of a clutch control lever 98 pivotally mounted upon a pin I80 on the frame. The lever 98. has a relatively short arm I62 extending upwardly above the pivot and a relatively long third arm I84 extending forwardly in a substantially horizontal direction.

A treadle lever I86 extends upwardly through an opening in the arm IM and. is provided with nuts I98 and II 0 threaded on it above and below the arm at a slightly greater distance apart than the thickness of the arm, softhat upon vertical movement'the'treadle lever will impart rising or falling movement to the arm I04, but will provide for some, lost motion betweenthe; treadle lever V and the arm. A compressionspring I I2, housed between a nut H4 at the upper end of the lever I88 and a fixed lug M8 on the frame, tends normally toraise the treadle lever and to maintain the clutch control lever 98 in such position as to hold the clutch bolt 9!! in its withdrawn position. Before the die I 4 is lowered into contactwith the work, the rearward end H5 of the lever 49 for lowering it abuts against the fort ward face"II7! of the upstanding arm I82,

thereby preventing rotation of the latter ina counterclockwise direction, as would be necessary to withdraw the wedge block 94 from engagement with the clutch bolt 88. .75 ever, the lever H8 is moved to lower the die into When, how-' engagement with the work, its rearward end will be raised out of contact with the arm I82, thus freeing the lever 98 for operation by the treadle lever I86. When the latter is depressed, the wedge block 94 will be moved rearwardly out of engagement with the clutch bolt 98, thus releasing the latter to action of the spring 92 to cause a coupling of the driving pulley 38 to the drive shaft 28.

Mechanism is provided to prevent inadvertent repetition of the operation of the machine and also to provide for a dwell of the die upon the work, if desired, as when the die includes heated embossing members. This mechanism causes the clutch to b automatically thrown out of operation when the block I8 is at the bottom of its stroke with the edge of the die in contact with the work support I2, after having cut through work positioned thereon. The mechanism comprises a clutch release lever H8 positioned at the forward side of the drive shaft 28 and mounted on a transverse pivot I28. At its upper end, diametrically opposite to the wedge block 84, the lever II8 carries a second wedge block I22 urged inwardly by a spring I23 to engage the clutch bolt 98 during the rotation of the drive shaft, and thus to withdraw the clutch bolt from the driving pulley when the shaft has made a half rotation and the block I8 actuated thereby is at the limit of its downward movement. This arrangement is such that the treadle lever I86 must be permitted to rise before the machine can complete itscycle and restore the die to its original raised position.

In order to cause th clutch bolt 98 to be reengaged, the arm I84 is provided with a forwardly extending rod I24 projecting in line with the lever H8. When the treadle lever I85 is allowed to rise, the clutch control lever 98 swings in a clockwise direction about its pivot (Fig. 1) and thus not only restores the wedg block 94 into position to withdraw the bolt 98, when the shaft has completed its rotation, but also causes the rod I24 to strike against the upstanding lever H8, and thus rock it forwardly to withdraw its wedge block I22 from engagement with the bolt thereby to allow the bolt to reengage the driving pulley and thus to cause the drive shaft to make the second half of its rotation.

It is sometimes desirable to prevent actuation of the clutch even after the die has been lowered into engagement with the work, for example in case it is desired to try out the effect of various adjustments of the machine, or to give mechanical attention to it. To accomplish this, the frame is provided with a downwardly extending bracket I26, which houses a transversely slidable rod I28 projecting horizontally towards the frame of the machine. Th rod I28, when extending far enough toward the main body of the machine, lies underneath and close against the forward end of the arm I84 of the clutch control lever 98 and thus prevents rocking movement of this lever to operate the clutch; even though the treadle lever I86 has been depressed. When, however, it is desired to operate the machine in a normal manner, the rod I28 can be slid outwardly by means of a hand nut I38 to withdraw it from beneath the arm I84 and thus to allow the latter to be rocked freely by its treadle. In order to retain the rod I28 in either operative or inoperative position, the rod is provided with two shallow recesses, one of which is shown at I32, spaced apart along its axis, and a springpressed plunger I34 in the bracket I28 arranged to engage one or the other of said recesses. The rod I28 can also be slid toward the. body of the machine sufficiently to underlie a downwardly extending boss I38 on the lever 40, so that the downward movement of the die by accidental tripping of the treadle rod 44 is prevented.

The work support I2 is detachably secured in place beneath the di I4 by a clamping bolt I38, which facilitates the location of beds of different sizes and shapes in the machine.

lhe lower end of the plunger I 6 is enlarged to provide a substantial area of contact for the base plate 62 lying against it. In order to guard against the likelihood of the fingers of the op erator being caught between the base plate and the frame of the machine, the frame carries a shrouding member I48 which prevents entrance of the operators fingers between the block and frame.

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

1. A perforating machine comprising a work support, a plunger mounted for reciprocation heightwise of the support, a die carried by the plunger, a power-operated block for moving the plunger toward the die, said plunger having a wedge located at its upper end and engaging the block and movable to vary the physical length of the plunger, releasable means for locking the die on the plunger, and means associated with the wedge for preventing release of the die from the plunger except when the wedge is adjusted into position in which the lower end of the plunger is located at a predetermined distance from the block. I

2. A perforating machine comprising a work support, a plunger mounted for reciprocation heightwise of the support, a die carried by the plunger, power-operated means for moving the plunger toward the die, a wedge member forming part of the plunger and engaging the poweroperated means arranged for movement transversely of the plunger. for varying the distance between the power-operated means and the die, releasable means for securing the die to the plunger, and means operable in response to movements of the wedge member for preventing operation of the locking means until the wedge has been adjusted to space the die by a predetermined distance from the power-operated means.

3. A perforating machine comprising a work support, a plunger mounted for reciprocation heightwise of the support, a die carried by the plunger, power-operated means for moving the plunger toward the work support, means for varying the effective length of the plunger, means for locking the die on the plunger including a stem slidably mounted in the plunger, and a plate carried by the plunger and having a keyhole slot, through which the stem projects, arranged to prevent movement of the stem relatively to the plunger except when the die is located a predetermined distance from the poweroperated means.

HUBERT BOOTHROYD.

CERTIFICATE OF CORRECTION. Patent No. 2,257,087. September 50, 19in.

HUBERT BOO'I'HROYD.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, second column, line 5, for "seotinonal" read --sectional line 1+0, for "adopt" read -adapt'-; page 2, first column, line 15, for or" read --of--; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this lpth day of November, A. .D. 19141.

Henry Van Arsdale, (Seal) Acting Commissioner of Patents.

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