US2062692A - Power press - Google Patents

Description

Dec. 1, 1936. A T YATES 2,062,692

' POWER PRES S FiledvApril 6, 1935 3 Sheets-Sheet 1 De.1,1936. AT YATES 2,062,592

POWER P RESS Filed April 6, 1955 3 Sheets-Sheet 2 ff/f Dec., ,1, 1936. A Tl YATES 2,062,692

POWER lPRES S Filed April 6, 1935 3 Sheets-Sheet 5 JWM/Waff j?? M /j/Z MWI? Patented Dec. l, 1936 UNITED STATES PATENT @FICE POWER PRESS Application April 6, 1935, Serial No. 15,058

1 Claim.

This invention relates to pressing machines of the kind in which a die or cutting member is mounted on a reciprocatory plunger which may be operated at intervals as desired from a continuously moving reciprocatory or oscillatory ram or similar part, and in which the plunger may be adjusted toward and from the work-independently of the ram.

The objects of this invention are to provide a pressing machine of this kind of improved and simplified construction, and in which a positive action of the parts is assured; also to provide a machine of this kind with means of improved construction for connecting the power driven member with the tool carrying member for eifecting a return stroke of the plunger; also to provide improved means for disconnecting the plunger from the ram after the plunger has been returned to its upper or starting position; also to provide a machine of this kind with means of improved construction for manually moving the plunger toward and from the work for enabling the operator of the machine to correctly position the Work relatively to the punch, die or other tool; also to provide a machine of this kind in which the means for connecting the power driven member and the tool carrying member for effecting the working stroke of the tool carrying member are entirely separate and independent of the means for connecting these members for effecting the return stroke of the tool carrying member; also to improve the construction of floating heads of this kind in other respects hereinafter specified.

In the accompanying drawings:

Fig. 1 is a side elevation of the front portion of a press provided with mechanism embodying this invention.

Fig. 2 is a fragmentary front elevation thereof.

Fig. 3 is a fragmentary section thereof, on an enlarged scale, on line 3 3, Fig. 2.

Fig. 4 is a sectional plan view thereof, on line 4 4, Fig. 2.

Fig. 5 is a longitudinal central sectional elevation, on line 5 5, Fig. 2.

Fig. 6 is a fragmentary transverse sectional elevation, on line 6 6, Fig. 1.

Fig. 7 is a fragmentary view similar to that shown in Fig. 6, but showing some of the parts in dierent positions.

Fig. 8 is a fragmentary longitudinal sectional view thereof, on line 8 8, Fig. 6.

Fig. 9 is a fragmentary longitudinal sectional elevation thereof, on line 9 9, Fig. 6.

Figs. 10 and 11 are fragmentary transverse elevations thereof, partly in section, on a still larger scale showing' a latch or pawl retaining member in operative and inoperative positions.

Fig. l2 is a sectional view approximately on line I2 l2, Fig. 3.

Figs. 13 and 14 are fragmentary views, taken respectively on line l3 l3, Fig. 10, and line I4 |4, Fig. 11.

In Fig. 1 is shown the front portion of a punch press on which the improvements embodying this invention have been incorporated. It Will be understood, however, that it is not intended to limit this invention for use in connection With punch presses, nor with the particular type of press shown in the accompanying drawings, since it will be obvious from the following description that this invention is equally applicable to other presses and machines in which a movablev punch, die, or cutting member is mounted to be actuated only when desired by the operator from a continuously movable member hereinafter called -a ram. The particular machine shown in Fig. 1 includes a frame A formed of a pair of plates spaced and having a ram or movable member l5 varranged to move substantially vertically in any suitable or desired manner. In the construction shown, this ram or movable member is pivoted on one arm of a lever I6 fulcrumed in the bearing Il on the frame A of the machine, and the other arm of the lever is pivotally connected by means of a link I8, one end of `which is formed to cooperate with an eccentric i9 secured on a shaft 20 journalled on the frame of the machine. A relatively large gear 2l is also secured on the shaft 26 and is driven by means of a pinion 22 which may be driven from an electric motor or other source of power (not shown).

'Ihe particular machine shown is provided With a suitable tool support 25 on which a die or other tool 26 may be secured in fixed relation to the machine, and 2l represents a punch or movable tool or die arranged to cooperate with the stationary die 26. As has already been stated, these dies may be replaced by tools of other types. The punch or die 21 may be secured by any suitable or desired means to a plunger 28, which is vertically movable in a stationary head or plunger guide 29. During the operation of the machine, the plunger 28 is normally disconnected from the ram or continuously reciprocatory member l5, except when a foot treadle 30 or other suitable actuating means is moved into operative position by the operator. In the particular machine illustrated in the drawings, a block 3l is provided which is movable rearwardly into' an inoperative position out of the path of movement ofthe movement will engage the block and through the medium of the block, will force the plunger 28 downwardly to the lower limit of its Working stroke.

Any suitable means may be provided for moving the block 3| into and out of its operative position between the ram and the plunger, and in the particular construction shown, this is done by means of the foot treadle 30, which is pivoted at 34 on a xed part of the machine, and which is connected by means of a link 35 with an arm 35 rigidly connected with another arm 31, both of these arms being movable together about the axis of a rod or shaft 38. The arm 31 is connected by a link 39 with another arm 4|! movable about the axis of another rod or shaft 40a and a weight 4| is also arranged to swing about this axis and is rigidly connected with the arm lll). An upwardly extending arm also secured in xed relation to the arm 40, is connected by means of a link 42 with the slidable block 3|. The weight 4| is so disposed as to normally withdraw the ram block into its rear or inoperative position and through the medium of links 39 and 35 and the rock shaft 31, this weight 4| also holds the foot treadle 30 normally in its upper position and returns the foot treadle to this position after each actuation thereof. Any other means controllable by the operator of the machine for moving the ram block 3| into and out of its operative position may, however, be used in place of the foot treadle and its associated parts which have been described.

The construction of the plunger and the stationary guide therefor may be of any suitable kind, and in the particular machine illustrated, the plunger guide 29 includes a guide block 45 which may be suitably secured to the frame A, for example, by means of bolts 41 extending through lugs 4.6 on the frame plates and into threaded holes in the plunger guide block 45, and the guide block may also have a recess or notch 43 in the rear portion thereof into which a bolt 44 of the frame A extends, for correctly securing the plunger guide on the frame of the machine, see Fig. 5. Any other means for mounting the plunger guide on the frame of the machine may be used, if desired.

The plunger guide member 45 has a pair of forwardly extending flanges 48 which are spaced apart and between which the plunger 28 is movably arranged. A front or cover plate 49 extends across the front of the head 29 and is secured to the outer ends of the forwardly extending flanges 43 and serves to confine the plunger 28 in the space between the two flanges 48.

The plunger 28 which is shown in the drawings is substantially of U-shape, being provided with a lower transverse body portion 50 and upwardly extending legs 5| and 52, and the ram I5 is movable up and down in the space between these two legs, without, however, engaging the transverse portion 50 of the plunger. In order to guide the ram I 5 in its movement relatively to the plunger, the ram may, for example, be provided with a longitudinal keyway or slot 53 into which a pin 54 extending through and secured to the leg 5| of the plunger may project. Any other means for guiding the ram in its movement with reference to the plunger may be employed, if desired.

The legs of the plunger bear against the forwardly extending flanges 48 of the plunger guide and against the front plate 49, as clearly shown in Fig. 4.

The lower end of the ram I5 during its up and down movement does not engage the transverse or body portion 50 of the plunger, and consequently, when the parts are in the position shown in Fig. 5, the ram cannot actuate the plunger. When, however, the block 3| is moved upon the transverse part 5U of the plunger into a position to be engaged by the lower end of the ram, then the ram will impart downward movement to the plunger 28. The block 3| may be of any suitable or desired construction, and is guided to move on the transverse portion 50 of the plunger. Preferably the block 3| has outwardly extending iianges 55 at opposite sides thereof, Figs. 6 and '1, which extend into slots formed by overhanging portions 56 of the two legs of the plunger, so that the block is guided to move only in a fore and aft direction on the plunger into and out of operative relation to the ram, and this motion, as has been explained, may be accomplished through the medium of the link 42. The lower portion of the block shown rests atly upon a corresponding fiat surface of the transverse portion 50 of the plunger, while the upper portion of the plunger block may be concave or recessed so as to t a corresponding convex curvature of the lower end of the ram. A block of other shape may, however, be employed, if desired, and a stop screw 51 may cooperate with the end of a recess 58 in the lower surface of the block, to limit the extent to which the block may be moved forwardly to correctly position the same below the ram.

From the foregoing description, it will be obvious that when the foot treadle is depressed, the block 3| will move into its correct position underneath the ram and upon the next downward stroke of the ram, the plunger will be moved downwardly to the lower limit of its working stroke. The ram, however, merely exerts downward pressure upon the block, and consequently, other means are provided for connecting the plunger with the ram tomove the plunger upwardly into its initial or upper position. In machines of this kind it is, of course, very important that the plunger only moves through a single working stroke and does not repeat its operation, except when desired by the operator, since such repeating may injure the o-perator and damage the work. I, consequently, provide separate and independent means for effecting the working and return strokes of the plunger, so that failure of the return stroke mechanism to operate will not affect the mechanism for producing the working stroke and will, consequently, not cause the machine to repeat its working stroke. This arrangement also makes it possible to start to move the block 3| out of its operative position as soon as the working stroke is completed, so that there is ample time for such movement and correspondingly less danger of having the block still in operative position when the next down stroke of the ram begins. The particular means for returning the plunger which are shown in the accompanying drawings include a connecting member or pawl which is constructed to form a connection between the ram and the plunger to produce upward movement of the plunger by the ram. In the construction illustrated, this pawl or member is pivotally mounted on the plunger, for example, to swing about the axis of a rod or shaft 60, and has a part or finger 6| which is yieldingly moved into a notch or recess 59 in the ram, for example, by means of a weight 62, which may be formed integrally with or otherwise connected with the pawl finger 6|. It will be understood that when the pawl is in the position shown in Fig. 6, upward movement of the ram I will result in corresponding upward movement of the plunger 28, and it will be further noted that the arrangement of the pawl and of the recess in the ram is such that downward movement of the ram will merely swing the pawl out of the recess and will not tend to transmit downward movement of the plunger through the pawl.

Means are preferably provided for holding the pawl out of operative relation to the ram l5 except when the ram actuates the plunger, so that the plunger may be adjusted relatively to the work, as many be desired, without interference by the pawl. Any suitable means may be provided to hold the pawl out of engagement with the ram, and in the embodiment of the invention illustrated, a latch 65 is employed, see particularly Figs. 10 to 14, which is adapted to engage in a notch or recess 66 formed in the pawl when the pawl is in a position out of the notch or recess 59 in the ram. The latch 65 may be of any suitable or desired construction, and in the form illustrated in the drawings, it is mounted on the inner face of the leg 52 on the plunger and has a limited movement relative to the plunger, sufficient to move into and out o-f the notch in the pawl. In the construction shown, this movement is provided for by guide slots 61 through which screws or pins 68 extend, the screws being fastened to the leg 52 of the plunger and the latch has a detent portion 69 adapted to engage with the recess or notch 66 in the pawl. The latch also has an arm 10 extending into an upright notch or recess 1l formed in the guide block 45 of the press. At the lower end of this notch or recess, a set screw 12 is preferably provided, which may be held in place by means of a lock nut 13 and with the upper end of which the arm 10 of the latch may engage when the plunger approaches the lower limit of its travel or working stroke. This engagement of the arm 10 with the set screw 12 will, consequently, cause the latch 65 to be raised out of engagement with the recess 66 in the pawl and will thus permit the pawl to swing into a position in which the pawl finger 6l can enter the recess 59. The pawl and latch will then occupy the relative positions shown in Fig. 6. When the ram has moved the plunger tothe upper end of its return stroke and the ram begins to move downwardly, relatively to the plunger, as would be the case if the block 3l has been moved into its inoperative position, then the downward movement of the ram will cause the pawl to be swung into a position in which the latch 65 may again enter into the recess 66 of the pawl, as shown in Fig. 7. The pawl will, consequently, form a connection with the ram only from the instant that the plunger reaches approximately the lower end of its stroke, until the plunger has been returned to the upper end of its stroke and the ram has started its do-wnward movement relatively to the plunger. The actuation of the pawl is, consequently, entirely automatic and independent of the movement of the block 3l, and the pawl remains inoperative until the plunger is moved through the last portion of its working stroke.

Any suitable or desired means may be employed for adjusting the plunger 28 with reference to the work X on the lower die 26. In the particular construction shown, an adjusting wheel 15 is employed for this purpose, which may be mounted to rotate about a pin or stud 16 suitably secured tothe plunger guide block @l5 or other fixed part of the machine, see particularly Figs. 4 and 12. A pin 11 may be employed to secure the stud 16 in place. The hub of the wheel 15 preferably is clamped or otherwise suitably secured to a sleeve 18, for example, by means of a disk or washer 19 and a bolt 86 secured to the stud 16. The sleeve 18 has rigidly secured thereto a yoke member 8| having a portion extending around the sleeve 18 and secured thereto by means of a key or pin 82. The yoke also has an outwardly extending slotted portion 83 into which a pin 84 extends, the other end of the pin being rigidly secured to a portion of the leg 52 of the plunger. Consequently, by turning the wheel 15 through a portion of a revolution, the yoke member 8| Will move the pin 84 either up or down, and the plunger will be moved accordingly. A spring 85 is preferably arranged in an aperture 86 in one of the forwardly extending anges 48 of the plunger guide and presses upwardly against the pin or extension 84, which pin is movable up and down in a slot 81 in the flange 48 of the plunger guide. The spring, being arranged at one side of the plunger and its guide, has been found ample to counteract the weight of the plunger, particularly when a relatively heavy grease is used between the plunger and its guide, so that the plunger will remain in any position in which it may be set by means of the adjusting wheel 15.

I claim as my invention:

The combination of a reciprocatory tool carrying member, a power driven member movable through a working stroke and a return stroke independently of said tool carrying member, a block movable into a position between a portion of said tool carrying member and a portion of said power driven member for causing said power driven member to move said tool carrying member through its Working stroke, a pawl arranged to move into operative engagement to form a connection between said members to move said tool carrying member through a return stroke, said pawl being moved into an inoperative position by the first portion of the working stroke of said power driven member when moving independently of said tool carrying member, a latch for holding said pawl in its inoperative position, and means adapted to be engaged by said latch when said tool carrying member moves through the final portion of its working stroke for disengaging said pawl to permit the same to move into its operative position.

ARTHUR T. YATES.

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