US2212874A - Die - Google Patents

Description

Aug. 27, 1940. f RE M 2,212,874

DIE

Filed May 26, 1939 2 Sheets-Sheet. 1

c. M. BREHM Aug. 27, 1940.

DIE

Filed M 26, .1939

2 Sheets-Sheet 2 .Patent ed Aug. 27,1940

UNITED STATES PATENT lorries 2,212,874 Dm- Charles M. Brehm, Springfield, hio,- assignor' to The Steel Products Engineering Company, Springfield, Ohio, a corporation of Ohio Application May 26, 1939, Serial No. 23,868

This invention relates to apparatus for trimming formed articles, and more particularly to punch and die construction having relatively movable cooperating parts which shiftlaterally with respect to'one another to. trim the edgesof a partially formed blank.

One object of the invention is the provision of a trimming die of the character,mentioned having a cam b1ock,.'oi comparatively small depth, which is slidably carried by a reciprocable pressure plate and arranged to shift laterally while the blank is firmly supported, the cam block and .pressure plate being so constructed as to accommodate articles or blanks of comparatively large depth. r

Another object of the invention is the provision of a die or thecha'racter' mentioned including a cam block having cams which-control its 'lateral shii'ting movement as the cam block is depressed, the lowersuriaces of the cams being slidably supported directly on an upwardly proecting portion of a reciprocable pressure plate which is slidably guided for rectilinear movement and which is urged upwardly'by yielding cush-n ioning means acting in opposition to the punch. Other objects and advantages of the invention will be apparent from the following description and the appended claims,- taken in'connection 30 with the accompanying drawings, in' which Fig. ,1 is a vertical sectional view through a tr1mming die embodying the present invention, and showing its relation to a cooperating trimming punch;

Fig. 2 is a perspective view of the midportion of a press in which the trimming die and punch are mounted;

Fig. 3 is a sectional view showing aportion of the trimming die arranged to receive a blank or shell of comparatively large depth; and

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

Referring more particularly tothe drawings, in which a preferredzembodiment oi the invention has been shown, the apparatus is adapted to trim the edges of a partly. formed blank, such as a sheet metal shell, the trimming operation,

' being effected by relatively movable portions of movement with respect to-the trimming part l6 during the trimming operation. As shown, t e clamping member I! is carried by rods l8 ha g lower heads received in sockets in member I! and projecting upwardly through clearance passages in the trimming part 16.. 'l7he,rods extend slidably through thrust plates 20 which rest in suitable pockets in the plate l5. Springs IBQengaged with: the'thrust plates and with collars fixed on the, rods serve to yieldingly hold the member l'lup againstjthe lower flat surface of the trimming part l6 while permitting relative shifting movementof parts l6 and l1.

The trimming die II, which is carried by the Qbolster plate 22 of the press, comprises a stationary supporting member 23' havingan aperture 24 of suitable size to receive a pressure platev 25 and a cam block 26. The pressure plate is slid ably guided for reciprocatory'rectilinear move- .ment on guide'surfaces 2'! .of the supporting member 23, and slidably supportsthe cam block 26 for lateral shifting movement during the trimming operation The cain block 26 comprises a hollow body portion andcams-2'l seemed, thereto as by .means of bolts 28. Also secured or bolted to the body portion of the cam block-is an upper trimming plate 29, adapted for cooperation with the trimming part It of. the punch. Fixed to the supporting member'23, at opposite sides of the cam block, are cam-members 3| having cam sur- .30 faces adapted for cooperation with the cam surfaces provided on the outer sides of the cams 2T which are of such form that as the cam block is lowered by the punch, the cam block will be laterallyshifted back and forth, preferably in .four difl'erent directions, so that the partially formed blank or shell 33 will be trimmed in one stroke of the press as the blank, together with the trimming plate 29 and the clamping mem-q her I! are shifted back and forth witlirespect to the trimming part I 0 01' the punch.

The depth of the clamping'member I'I determines the height of the shearing point with. respect to the bottomof the blank so that member. I'I functions as a gauge as well as aclamping -member for the blank.

Extending across the lowerside or the body portion of the cam block is a supporting part-34,

providing a support for a series of springs; 35

which engage, at their upper ends, against a movable ejector plate 36. The part 34-, as shown in Fig, 1, is detachably mounted on the lower sur-. face of the body portion'df the cam block byv meansof screws or bolts 31, and proiects-downwardly from the bottom of the cam block with the middle portion of 'the beam arranged a considerable distance below the bottom of the cam Normally the ejector plate 35 is held in ele-.

vated position by means of the springs 35, its outermost position being determined by stop nuts 40 screwed on studs 42 which project downwardly from the ejector plate. These nuts 40, which are normally held against rotation by suitable positioning dowels 43, are normally engaged in conical sockets 44 provided on the lower side of part 34. As-will be apparent from Fig. l, the ejector plate 36, when depressed by the punch, is approximately at the level of the bottom of the cam block so that when comparatively small blank clamping members ll and 39 are employed, as shown in Fig. 3, the device is adapted to handle work pieces having a depth substane tialy equalling or even exceeding the depth of the cam block.

.The pressure plate 25 as well as the part 34 is so constructed that its central wall portion is considerably below the bottom of the cam block)! Theupwardly extending portion of the press e plate, on which the bottom surfaces of the cams 21 are slidably carried, is guided in the supporting member 23 while the transversely extending wall portion 45 is carried on pins 46 which operate through guide'holes in the bolsterplate 22. The lower ends of the pins are yieldmgly pressed in an-upward direction by means of a suitable air or spring cushion; As shown in Fig. 1, the lower ends of the pins rest on a spring pressed plate 41, the lower ends of the springs being supported on stationary beam 48. r In operation, the partially formed blank 33 is placed on the blank clamping members 39, the slide I! of the press being in its elevated position, and the cam block and the ejector plate also being in their raised positions. The slide I2 then descends, and the clamping member I! of the punch engages the bottom of. the blank and clamps it against the clamping members 39 of the die, the continued descent of the punch then causing the blank to descend in the die as the springs 35 yield to permit this. The parts thus assume the positions shown in Fig. l with the peripheral portions ofthe clamping part I! of the die extending closely adjacent the inside of the upwardly extending walls of the blank with sufllcient clearance therefrom to provide for freelywithdrawing and inserting the clamping member within the shell. Atthis time the lower surface of the trimming part l6 of the punch is substantially flush with the upper surface of the trimming plate 29, and pins or lugs 50 which are carried by the plate [5 are engaged with the upper surface of the trimming plate. The continued descent of the punch then forces the cam block downwardly in the supporting member 23 against thejaction of the pressure plate 25, and

asthe cam block descends it is caused to shift laterally first in one direction and then another, to move the blank with respect to the trimming part l6 and trim the edges of the blank by the time the punch reaches its lowermost position. As the punch is raised by the continued operation of the press, the cam block moves upwardly with it, sliding onthe pressure plate and shifting back and forth again until the position of the parts shown in Fig. 1 again obtains, As the punch continues upwardly, the clamping member l1 moves upwardly, permitting the springs 35 to return the ejector plate to its normal position, thus raising the upper portion of the trimmed shell out of the trimming plate 29 to a position from which the shell can be readily removed. During the operation sufficient lubrication is afforded between the cams and the pressure plate from oil which is supplied to the cams, since the cam block is slidably supported on a surface which is at the level of the bottom of the cams 21.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein Without departing from the scope of the invention which is defined in the appended claims.

- What is claimed is:

A die adapted for cooperation with a trimming punch, comprising supporting means having an aperture, cam members fixed on said supporting means, a cam block operable in and movable axially of said aperture and having cams engaging said cam members for laterally shift.-

ing the block as the block moves along the aperture, a blank clamping memberarranged below the top of the cam block and shiftable laterally with the block and the blank for holding the blank during the trimming operation, yielding means urging said clamping member outwardly,

a reciprocable pressure plate having sliding engagement with the cams of the cam block and providing for lateral shifting of the cam block thereon during the trimming operation, said plate having an upwardly extending peripheral wall slidably supporting said cams and slidably mounted in said supporting means and having a bottom wall spaced substantially below the bottom of the cams.

2. A die adapted-for cooperation with a trimming punch, comprising supporting means having an aperture, cam members fixed on said supporting means, a cam block operable in and movable axially of said aperture and having cams engaging said cammembers for laterally shifting the'block as the block moves along the aper- Y member outwardly, said blank clampingmember,

saidsupporting part, and said yieldable means being shiftable laterally with-the cam block and relatively stationary with respect to the blank during the trimming operation, and a reciprocable pressure plate on which the cam block is slidably supported for lateral shifting movement during the trimming'operation.

3. A die adaptedfor cooperation with a trimmingpunch, comprising supporting means havingan aperture, cam members fixed on said supporting means, a cam block operable in and movable axially of said aperture and having cams engaging said cam members for laterally shifting the block as the block moves along the aperture, a blank clamping member arranged below the top of the cam block and adapted for cooperation with the punch to hold the blank during the trimming operation, a supporting part secured to and extending across one end 01' the cam block, yielding means'carried by said supporting part for urging said clamping member outwardly, said blank clamping member, said supporting part, and said yieldable means being shiftable laterally with the cam block and relatively stationary with respect to the blank during the trimming operation, a reciprocable pressure plate on which the cam block is slidably supported for lateral shifting movements during the trimming operation, said supporting means slidably guiding said pressure plate for reciprocatory movement, and means exerting an upward pressure on said pressure plate, the inner por-. tions of, said supportingpart and of said pressure plate being depressed substantially below the bottom of the cam block to provide for the reception of blanks of widely difiering heights.

4. A die adapted for cooperation with a trim ming punch, comprising supporting means having an aperture, cam members fixed on said supporting means, a cam block operable inand movable axially of said aperture and having cams engaging said cam members for laterally shifting the block as the block moves along the aperture, the lower end of the block being substantially at the level of the lower end of the cams, a blank clamping member arranged within the cam block and adapted for cooperation with the punch to holdthe blank during the trimming operation, yielding means urging said clamping member outwardly, said clamping member and said yielding means being shiftable laterally with the cam block and relatively stationary with respect'to the blank during the trimming operation, a reciprocable pressure plate slidably guided clamping portion of the plmch to hold the in said supporting means and having sliding en'- gagement with the cam block to provide for lateral shifting of the cam block thereon during the trimming operation, saidplate having a depressed central wall portion located substantially below the surface on which the cam block is slidably engaged.

5. In combination, a trimming punch having a trimming portion and a laterally shiitable blank clamping portion, and a die adapted for cooperation with said trimming punch, said die comprising supporting means having an aperture, cam members fixed on saidsupporting means, a cam block operable in and movable axially of said aperture and having cams said'cam members for laterally shifting the blocka's the,

ming punch, a blank clamping member arranged within the cam block. with the said pressure plate.

during the trimming operation, a supporting part fixed to and extending across the lower end of the cam block, yielding means carried by said supporting part for urging the clamping member of the die-towards the clamping portion of the punch, said blank clamping member, said supporting part, and said yielding'means being shiftable laterally with the cam block and relatively stationary with respect to the blank during the trimming operation, a reciprocable pressure plate slidably guided in said supporting means and having sliding engagement with the cams ofthe cam block at a point substantially even with the lower end of the cam block and thereof relative to the plate from an initial central position, and a die adapted for cooperation with said trimming punch, said die comprising supporting means having an aperture, cam members fixed on said supporting means, a cam block operable in and movable axially of said aperture under the action of said pressure members and having cams engaging said cam members for laterally shifting the block as the block is moved along the aperture, a blank clamping member arranged within the cam block cooperating with the clamping portion of the punch-to hold the blank during the trimming operation, a supporting part fixed to and extending across the lower end of the cam block, yielding means carried by said supporting part for urging the clamping member of the die toward the clamping (portion of the punch, said blank clamping portion and said blank clamping member being shiftable laterally with the cam block and being relatively stationary with respect to the blank during the trimming operation, a reciprocable pressure plate 'slidably' guided in said supporting means and 80 having sliding engagement with the cams of the cam block providing for lateral shifting of the cam block thereon during the trimming operation, said pressure plate having'a depressed central wall portion to provide for the reception of blanks oi widely differing heights, and cushioning means engaging said depressed wall portion block is movedalong the aperture by the trimand yieldingly exerting an upward pressure on CHARLES ML U

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