US3125917A

US3125917A - Punch and die assembly having spaced tool positioning plates

Info

Publication number: US3125917A
Authority: US
Publication date: 1964-03-24
Anticipated expiration: 1981-03-24

Description

March 24, 1964 s. G. F. SMEETS 3,125,917

PUNCH AND DIE ASSEMBLY HAVING SPACED TOOL POSITIONING PLATES:

Filed Dec. 24, 1958 2, Sheets-Sheet l o l i' k) 2 \K 1 I; III! 1 52min? G'erara 61/7 Smeefs fiw' L ii .v s

March 24, 1964 G. F. SMEETS 3,125,917

PUNCH AND DIE ASSEMBLY HAVING SPACED TOOL POSITIONING PLATES Filed Dec. 24, 1958 2 Sheets-Sheet 2 Gerard G-ESmeefs United States Patent 3,125,917 PUNCH AND DIE ASSEMBLY HAVING S PACED TOOL POSITIONING PLATES Gerard G. F. Smeets, Brampton, Ontario, Canada, as-

signor to Houdaille Industries, Inc., Bufialo, N.Y., a

corporation of Michigan Filed Dec. 24, 1958, Ser. No. 782,872 12 Claims. (Cl. 83--14tl) This invention relates generally to a die set, and more specifically to an improved punch and die assembly including components which may be standardized for use in other like devices in various combinations.

Although the principles of the present invention may be included in various punch and die assemblies, a particularly useful application is made in a punch and die assembly adapted to be employed in punch presses. It will also be apparent that the principles of this invention may be employed in tooling of the progressive type wherein the workpieces initially comprise strip material which is ultimately incrementally severed.

Heretofore, it has been common to mount an apertured die plate in a die set, and to provide a punch element secured to the reciprocable portion of the die set for cooperation with each aperture in the die plate. After a job has been run, the entire die set is stored. When there is no need for any further manufacture of the device, the die set itself may be salvaged, but ordinarily the various punch and die elements contained therein must be discarded.

In a shop doing a considerable amount of stamping, a considerable capital becomes tied up in such tooling which is in storage. Also, the sum total of all breakage is also substantial and causes expensive production delays.

The present invention contemplates the utilization of tool elements which may be standardized and kept in stock in a variety of sizes. The tool elements are provided with similar mounting features and dimensions so that they can be readily removed and replaced in event of breakage. Further, the size of the punching can be altered at will by such replacement without rework of the tool. Still further, the tool and die assembly itself can be disassembled after a job has been run and stored in accordance with its several separable components. Only a few rnoments is required to put together an appropriate assembly of tool elements. To facilitate the foregoing, the invention includes an appropriate number of plate means which not only align tool elements with respect to each other, but which serve to support and/or guide tool elements, and in one instance one of the plate means also serves as a stripping means.

Accordingly, it is an object of the present invention to provide a novel punch and die assembly.

Another object of the present invention is to provide an improved punch and die assembly wherein individual punches and dies are secured in position without employment of screws or clamps for the individual tool elements.

Yet another object of the present invention is to provide an improved means for holding or restraining tool elements, by the release of which several such elements may be simultaneously released for removal.

A still further object of the present invention is to provide an improved punch and die assembly including at least one tool aligning plate means therein.

3,125,917 Patented Mar. 24, 1964 "ice Yet another object of the present invention is to provide a structure wherein punch and die elements may be disposed extremely close to each other.

A still further object is to provide means for positioning non-circular tool elements to preclude relative lateral movement thereof.

Yet another object of the present invention is to provide a punch and die assembly wherein only plate means contained therein are unique to a particular job, and wherein all the other elements may be more or less universally employed.

Many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.

On the drawings:

FIGURE 1 is a cross-sectional view, partly in elevation, of a punch and die assembly provided in accordance with the principles of the present invention;

FIGURE 2 is a fragmentary top view, partly broken away, of the structure shown in FIGURE 1; and

FIGURE 3 is a view taken along line IIIIII of FIG- URE 2.

As shown in the drawings:

The principles of this invention are particularly useful when embodied in a punch and die assembly such as illustrated in FIGURE 1, generally indicated by the numeral 10. The punch and die assembly includes an upper shoe means generally indicated at 11, a lower shoe means generally indicated at 12, an upper guide or alignment means generally indicated at 13, a lower guide or alignment means generally indicated at 14, a movable plate means generally indicated at 15 which is movable relatively to the upper shoe means 11 and which is slidably supported on the upper guide means 13, a fixed intermediate plate means In supported on the lower guide means 14, and an assortment of tool members disposed for mutual cooperation between the upper and lower shoe means 11 and 12.

The upper shoe means 11 includes in this embodiment an upper shoe 17, and the lower shoe means 12 includes a lower shoe 18. The

shoes

17 and 18 are disposed in fiatwise spaced parallel relation to each other and are each adapted by conventional means (not shown) to be secured to a stamping press, press brake, or similar machine wherein one shoe is reciprocated toward and away from the other.

The assembly 10 is adapted to receive a workpiece, not shown, intermediate the

shoes

17, 13. Intermediate the workpiece zone and the shoe 18, there is disposed a pair of plate means which in this embodiment includes the fixed intermediate plate means 16, and a lower plate means 19 which in certain embodiments may comprise a part of the lower shoe means 12. The plate means 16 and 19 may be made identical to each other.

Intermediate the workpiece zone and the upper shoe 17, there is provided another pair of plate means including an upper plate means 20 and the movable plate means 15. The movable plate means 15 comprises a selectable number of identical plates here shown to include the

plates

21 and 22. As Will become apparent, the plate means i 3

i l

15, 26 are each operative to align various tool elements. The piate means 15, 26 may also be substantially identical to each other and may be substantially identical to the plate means 16 and 19. The plate means 15 also serves to strip the workpiece from the tool elements.

The plate means 15, 16, 19 and 21) are each provided with four locator apertures 23 disposed in this embodiment in a rectangular arrangement. Each of the plate means 15 (21, 22), 16, 19, and 20 comprises sheet metal of such thickness that the various plate means may be initially punched to provide all apertures therein. The term sheet-metal plate means as used herein embraces this inherent property. Means are received in each of the locator apertures 23 which means has a snug fit therewith to preclude lateral or angular movement of any one of the plate means with respect to the shoes or with respect to each other. Accordingly, to this end, there are provided at least two locator apertures 23 in each of the plate means 15, 16, 19 and 26. It will be noted that the corresponding locator apertures 23 of the various plate means are axially aligned with each other. The upper guide means 13 is received in the apertures 23 of the plate means 15, 26, while the lower guide means 14 is received in the apertures 23 of the plate means 16, 19. The upper guide means 13 reciprocably interengages with the lower guide means 14 in a snug fashion so that the axis of the locator apertures 23 of each of the upper pair of plate means is maintained coaxial with the axis of each of the corresponding locator apertures 23 in the plate means 16, 19.

The lower guide means 14 includes a cup-shaped guide bushing 24 having a radial flange 25 at its mouth which engages the upper surface 26 of the plate means 16, which surface or side is the one directed toward the workpiece. A tubular bushing or spacer 27 surrounds the cup-shaped guide bushing 24, and in this embodiment extends axially to engage the lower surface 28 of the plate means 16 and the upper surface 29 of the lower plate means 19. The cup-shaped guide bushing 24 is provided with a generally axially located hole 36 through which threaded means here comprising a cap screw 31 extends for threaded engagement with the shoe 18, whereby the fixed intermediate and lower plate means 16 and 19 are rigidly and removably supported, aligned, and maintained in alignment.

The upper guide means 13 includes a guide member 32 removably secured by a cap screw 33 to the upper shoe 17. The guide member or pin 32 has a flange portion 34 which serves to space the upper plate means 20 from the shoe 17. Adjacent axially to the flange 34 there is a cylindrical surface 35 which closely fits with the upper plate means 26 and is received within the locator aperture 23 thereof. An extension of the cylindrical surface 35 is threaded as at 36 and receives a nut 37 which securely clamps the upper plate means 20 against the flange 34 of the guide member 32. Axially adjacent the threads 36, there is a reduced cylindrical portion 38 and adjacent to the portion 38 there is a guide portion 39 of larger diameter which defines with the portion 38 a shoulder 46). An annular guide bushing 41 having a flange 42 acting against the lower surface 43 of the movable plate means 15 has a cylindrical surface 44 corresponding in size to the cylindrical surface 35 and to the outside of the guide bushing 24, which is snugly received within the locator apertures 23 of the

plates

21 and 22. An axial extension of the cylindrical portion 44 is threaded as at 45 for receiving a nut 46 which engages therewith to clamp the

plates

21 and 22 against the flange 4?. of the bushing 41. The interior surface of the bushing 41 forms a close sliding fit with the guide portion 39 of the guide member 32. A set screw 47 extends through the nut 46 and engages the shoulder 46 to limit the distance which the movable plate means 15 may move toward the workpiece zone. From a limiting position where the set screw 47 engages the shoulder 40, the bushing 41 and the nut 46 may move together with the

plates

21, 22 in a direction toward the shoe 17, and return to this limiting position. It is apparent that since the inside dimension of the guide bushing or bearing 41 is the same as the inside dimension of the guide bushing 24, the cylindrical portion 39 of the guide member 32 acts to maintain alignment between the upper guide means 13 and the lower guide means 14. It is also apparent that since the cylindrical portion 39 is concentric with the cylindrical portion 35, the guide member 32 together with the annular slidable clamping means 41, 46, acts as a means for maintaining the locator apertures 23 of the plate means 15, 26 in alignment and for supporting such plate means.

For any particular punching job, a particular punch and die assembly includes a suitable number and selection of tool elements. These include round punches, shaped punches, workpiece guide pins, and a cutoff tool in the illustrated embodiment.

In each of the plate means 15, 16, 19 and 20, there is an opening or tool aperture 48 coaxially aligned with the corresponding apertures of the other plate means. Other tool openings or apertures 4352 are also provided and similarly aligned and arranged so as to jointly constitute a group of aligned tool apertures, each coaxially aligned with the corresponding apertures of the other plate means. The tools carried in the apertures 4852 each includes a die means generally indicated at 53, and a punch means generally indicated at 54. The die means 53 includes an elongated die support 55 having a lower end 56 adapted to be supported in endwise engagement. In this embodiment, the die support 55 has a larger sectional dimension than the apertures 4852 and so the lower end 56 is provided with an undercut so that the lower end 56 is sized the same as the tool aperture which receives it. Thus in this embodiment, the lower end 56 engages the upper surface 57 of the shoe 18. The upper end 58 of the die support 55 is provided with a die receiving recess 59 and an upwardly directed shoulder 60 which engages the lower surface 28 of the fixed intermediate plate means 16. A replaceable die button 61 is removably received in the die receiving recess 59, each die button having a cutting portion 62 properly aligned with the tool aperture for cooperation with another tool element. The die element or button 61 is provided with a peripheral configuration corresponding to the tool aperture in which it is disposed and having a relatively snug fit therewith. While the fixed intermediate plate means 16 is most effective for locating the various cutting portions 62 of the die, the lower plate means 19 is effective, along with the die support 55 when the die means is of two-piece construction, to insure that the die aperture is not cocked. Each of the die supports 55 is provided with a slug chute 63 which communicates with the die opening and the cutting edge 62 thereof.

The punch means 54 which co-operates with the die means 53 includes a punch element 64, a stripping spring 65, and a guide and stripper button 66. The punch element 64 is provided with a flanged head 67 which is disposed between the upper punch template 20 and the shoe 17 and which has an axial length corresponding to the axial length of the flange 34 of the guide member 32. The punch element 64 has a punch bit 68 having a cutting edge 69 which co-operates with the cutting edge 62 of the die element 61. Likewise, therefore, the cutting edge 69 is aligned properly with the tool aperture through which it extends. To effect this alignment and to guide the punch bit 68 during its reciprocation, the guide and stripper button 66 is provided with an axial opening which receives the punch bit 68 for relative axial reciprocation. The guide button 66 is provided with a peripheral configuration suitably sized so as to snugly fit the tool aperture and so as to effect and maintain this alignment. The button 66 is also flanged so as to engage the upper surface 70 of the plate 21. Intermediate the flange of the button 66 and the lower surface 71 of the upper plate means 20, there is disposed the stripping spring 65 which acts on the guide bushing 66 to move it in a direction away from the shoe 17. It can be seen that the set screw 47 of the upper guide means 13 permits the spring 65 to move the plate 22 to a position where its lower surface 43 extends beyond or below the cutting edge 69. In this embodiment, the lower surface 73 of the guide button 66 is coplanar with the surface 43. It is apparent that if the surface 73 is recessed from the surface 43, the plate 22 acts as a stripper for engaging the workpiece to strip it from the punch bit 68. It can also be seen that if the surface 73 extends beyond the surface 43, the surface 73 engages the workpiece so that the button 66 also acts as a stripping button. However, when the

surfaces

43 and 73 are coplanar as shown, both of these surfaces act as a stripping surface for the workpiece. Thus the button 66 is a tool guiding means having a peripheral contour for being closely received in the tool aperture of the plate means. The shank of the punch 64, particularly adjacent to the flanged head 67 thereof, is likewise provided with a peripheral contour which permits snug engagement between the upper plate means 29 and the punch 64 whereby the punch is accurately held near its head to preclude cocking thereof. In a typical embodiment, the guide button 66 may comprise a drill bushing, and in this embodiment serves to accurately locate the cutting edge.

Another tool which is supplied in this embodiment is a workpiece guide or stop pin 74 having a lower end corresponding in size to the lower end 56 of the die support 55, having an upwardly directed shoulder 75 corresponding to the shoulder 69 on the die support 55 and an up per end 76 which is adapted to engage the workpiece in an edgewise manner, thereby to accurately position or locate it with respect to the other tools included in the device 19. The substitution of a difierent pin for the pin 74 is readily effected by the release of the cap screws 31. Such substitute pins, if they have a different diameter for the upper portion 76, would effect a proportionate change in workpiece position, which change is a function of the difference in radii. It can be seen that the stop pins 74 are not locked against rotation and hence any circumferential portion of the upper end 76 may be directed toward the workpiece. It is to be understood that a number of pins 74 are included in this embodiment so as to adequately guide the workpiece in its progress through the device It The

plates

21 and 22 are provided with apertures 77 aligned with those in the plate means 16 and 19, which comprise an aligned recess therein for receiving the upper end 76 of the guide pin 74.

The instant structure may also be utilized to receive punches having a shaped or non-circular punch bit. The general structure is similar to that already described. However, when a shaped punch is employed, its angular orientation with respect to the workpiece must be maintained. Accordingly, both the punch bit and the die must be maintained against rotation. To this end, the aperture 78 in at least the intermediate plate means 16 and one of the

plates

21, 22 is made non-circular, the peripheral portion of the die element 79 and the peripheral portion of the guide button 80 being provided with a corresponding configuration which prevents rotation. While there is any number of such possible configurations which will achieve this result, the instant embodiment includes a lug or key portion 81 integral with the plate means and received in a groove 82 in the mating button. The exact dimensions are so chosen as to preclude angular movement about the punching axis between the die element and the plate means 16 and between the guide element and the movable plate means 15. In this embodiment, the punch 83 is shown to have a punch bit with a flat surface 84 and the opening in the die as well as the opening in the guide buttons are each of a similar shape for co-operation with the non-circular punch bit 84. Thus in this embodiment, a plate means is employed to co-operate with each of the punch and die means respectively to preclude angular movement therebetween. Of course, a non-circular aperture may also be employed at the upper end of the punch 83 and at the lower end of the corresponding die support, whereby all of the plate means would be more nearly of identical configuration.

It is to be understood that where heavy work is to be punched, the number of plates in the plate means 15 to be provided may be increased so as to generally stiffen the entire structure for heavier duty stripping. It is also to be understood that an advantageous device may be provided wherein no guide button 66 is provided, its stripping, locating, and guiding functions being carried out directly by the plates of the plate means 15. This feature is illustrated by the punch 85, the upper end of which is disposed in the tool aperture 52, and which is provided with a punch bit that is directly received in a relatively smaller aperture 86 sized to correspond to the axial opening of a guide button which otherwise would be employed to cooperate with it. This type of construction has the advantage that no guide button is employed, but has the disadvantage that the plate means may be subject to wear.

The instant embodiment discloses a further tool which is supported, aligned and guided by the plate means thereof, such tool being a cut-off tool. The same general principles of construction have been provided for the cutoff tool which include a die means generally indicated by the numeral 87, and a punch means generally indicated by the numeral 88. The die means 87 includes a noncircular tool element or die element 89 received in a recess or slot 90 of a die support 91. The die support 91 is provided at its lower end 92 with a configuration which closely fits one end of a non-circular laterally elongated opening 93. In like manner its upper end 94 is provided with a configuration that closely fits the similar end of a similar opening 93 in the plate means 16. Likewise, an upwardly directed shoulder 95 engages the lower surface 28 of the plate means 16. The recess 90 is laterally larger than the portion of the die element 89 received therein so that a pair of

set screws

96, 96 carried by the die support 91 clamps the die element 39 therein. At the upper end of the die element 89 there is a cutting edge 97 which is disposed at the same general height as other die cutting edges in the device 19. Thus the die support 91 acts as a tool guide to maintain the cutting edge or portion 97 in a properly aligned relationship.

The die support 91 thus acts on a lateral edge of the die element 89, and as best seen in FIGURES 2 and 3, a die support 91 is provided at each end of the laterally elongated non-circular opening 93. The recess 90 of the die support 91 extends axially for the entire length thereof so that the die element 89 rests directly against the shoe 18. As'best seen in FIGURE 2, the transverse section of each of the die supports 91 is generally U-shaped, the recess 99 being defined by the legs of the U, and the open portion of each U-shape being directed toward the other. Thus by loosening the set screws 96, the die element 89 may be removed therefrom. By loosening the cap screws 31, the die means including both the die element 89 and the die support 91 may be removed as a unit.

To co-operate with the die means, the punch means 88 includes a non-circular tool or punch element 99 having a plate-like configuration disposed above the die element 89 for co-operation therewith. The punch element 99 is substantially identical to the die element except that it has been provided with a pair of pilot portions at each end, having chamfered lowered portions for reception into the recess 90. In the upper plate means 29 and in each of the

plates

21, 22 there is provided a non-circular laterally elongated opening 93 similar to the other openings 93 already described. In the upper plate means 20 there is provided a tool guide button 101 which acts as a tool guide means. The button 101 is provided with a recess 102 aligned with the unoccupied portion of the recess 90 for receiving a lateral edge of the punch blade element 99. A set screw Hi3 extends therethrough for securing the punch element 99 in position. The punch guide and support button 161 has a peripheral configuration which is received within the one end of the laterally elongated aperture 93 in the plate means 20, and has a flange portion disposed between the shoe 17 and the plate means 20.

Immediately below and in line with the punch guide button 161, there is a stripper plate guide button 104 having a flange portion engaging the upper surface 79 of the plate 21, and a peripheral configuration received within one end of the laterally elongated aperture 93 in the

plates

21 and 22. The guide button 1% is also provided with a recess 195 which receives a lateral edge of the punch element 99.

In this embodiment, each of the punch support button Mill and the punch guide button 164 actually comprise two similar elements, each received at opposite ends of the laterally elongated apertures 93. Thus, as best seen again in FIGURE 2, each of these buttons has a generally U-shaped sectional configuration wherein the legs of the U-shape respectively define the recesses M32 and ms, the open end of the U-shape of one button being directed to the open end of the opposite U-shape section. A stripping spring 1% is disposed intermediate each of the pairs of buttons 191 and 104 for urging the guide button 104 in a direction away from the shoe 17. Thus it is to be understood that the recess 1% permits relative sliding between the guide button Hi4 and the lateral edge of the punch element Q9.

During operation, the button lltll provides support and guidance for the upper end of the punch element 9). During operation the button 104 provides tool guidance and also acts at the ends of the elongated aperture 93 as part of the stripping means.

One of the die supports 91 is also provided with a second recess 167 which extends transversely to the recess 9% and which extends in the direction in which the workpiece moves through the assembly 10. Within the recess 107 there is adjustably received a mounting arm 108 which extends therefrom to the left as shown in FIG URE 1. At the distal end of the mounting arm 108 there is carried a workpiece stop 169 which is selectably positioned to limit the advance of the strip from which the workpiece is made. A set screw 110 locks the mounting arm 168 in a selected position.

Although many rearrangements and various minor modifications might be suggested by those versed in the art, it should be understood that i wish to embody within the scope of the patent warranted hereon all such embodiments as reasonably and properly come within the scope of my contribution of the art.

I claim as my invention:

1. In a punch and die assembly, the combination comprising: a lower shoe means having a recess coaxially aligned with the punch; an intermediate sheetmetal plate means having an opening; means remote from each die releasably supporting said intermediate plate means in fixed spaced relation to said lower shoe means and with said opening coaxially aligned with the punch; a die button axially slidably extending through said intermediate plate means opening remotely from said supporting means and aligned directly thereby; and a die support disposed between said shoe means and said intermediate plate means remotely from said supporting means, said support having a lower end corresponding in size to said recess and slidably extending into said recess in endwise engagement with said lower shoe means and aligned thereby, said support being adapted at its upper end to receive and support said die button, and intermediate plate means and said die support being freely slidably removable upon release only of said supporting means.

2, In a punch and die assembly for punching a workpiece, the combination comprising: a pair of flatwise spaced tool-aligning sheet-metal plate means each having at least one tool-receiving aperture, and operative to direc'tly engage and align a tool received therein, and disposed to receive the workpiece at one side of said pair substantially parallel to said plate means, each of said plate means having at least two locator apertures, remote from each tool-aligning aperture therein and coaxially aligned with the locator apertures of the other of said plate means; a shoe disposed at the other side of said pair of plate means; a pair of bushings each having a cylindrical guide bore opening at one end, said bushings respectively being snugly received in each pair of aligned apertures and each having a radially extending iange at said one end and a smaller hole in the opposite end, said flanges engaging that side of that one of said pair of plate means which is adjacent to the workpiece; a pair of tubular bushings respectively surrounding said first named bushings intermediate said pair of plate means and in endwise engagement therewith and operative to preclude movement of said plate means toward each other; a pair of screws having heads in said bores and extending through said holes and securing said first named bushings to said shoe; and a pair of guide members removabiy secured to said one shoe, said guide members being telescopically snugly received respectively in said cylindrical guide bores to align said pair of plate means with respect to said one shoe, whereby said plate means are supported on said shoe independently of each other.

3. In a punch and die assembly for punching a workpiece, the combination comprising: two pairs of mutually flatwise spaced tool-aligning sheet-metal plate means disposed to receive the workpiece substantially parallel to and intermediate said pairs, each of said plate means having a tool aperture receptive of a tool, and said plate means being operative on such tools to align them, each of said plate means having at least two locator apertures remote from each tool-aligning aperture therein and coaxially aligned with the locator apertures of the other of said plate means; alignment means extending through said coaxially aligned locator apertures of one pair of said plate means and operative to support said plate means independently of each other and to maintain said coaxial alignment for said one pair of said plate means;

and other alignment means extending through said coaxially aligned locator apertures of the other pair of said plate means and operative to support said plate means independently of each other and to maintain said coaxial alignment for said other pair of said plate means; said alignment means and said other alignment means being separably reciprocably interengageable to align said one pair of said plate means with said other pair of said plate means.

4. In a punch and die assembly the combination comprising: a pair of separable flatwise-spaced tool-aligning sheet-metal plate means, each of said plate means having at least two locator apertures remote from each toolaligning aperture therein, each of said plate means having a tool aperture coaxially aligned with the corresponding tool aperture in the other of said pair of plate means and being receptive of a tool, and said plate means being operative on such tools to align them, the tool aperture in the upper of said plate means being non-circular; means extending through said locator apertures releasably supporting said plate means independently of each other in fixed relation and operative to rigidly maintain the spacing of said plate means and said coaxial alignment; and a removable punch-receiving die retained by and between said plate means and including a die button having an external sectional configuration and size adjacent to its cutting end corresponding to and received in said noncircular aperture of the upper plate means to preclude relative angular movement, said die button having a noncircular axially directed opening for receiving and cooperating with a non-circular punch bit.

5. In a punch and die assembly, the combination comprising: a pair of fiatwise spaced tool-aligning sheet-metal plate means, each of said plate means having at least two locator apertures remote from any tool-aligning aperture therein and a tool aperture coaxially aligned with the corresponding tool aperture in the other of said pair of plate means; means extending through said locator apertures and operative to support said plate means independently of each other and to maintain said coaxial alignment and to define the spacing between said plate means; at least one of said tool apertures being non-circular and being in the lower of said pair of plate means; and a tool supported by said plate means and including a punch and guide button assembly snugly received in said non-circular tool aperture; said punch having a non-circular cutting bit directly restrained from rotation by the internal configuration of said guide button, said guide button having an external configuration and size corresponding to said non-circular tool aperture to preclude relative angular movement, and having a non-circular axially directed opening for snugly receiving and guiding the non-circular bit of said punch.

6. In a punch and die assembly, the combination comprising: a pair of fiatwise spaced shoes disposed to be reciprocated toward and away from each other; at least four guide means, two of said guide means being fixedly secured to one of said shoes and the other two of said guide means being fixedly secured to the other of said shoes, the two guide means of one shoe projecting therefrom toward the other of said shoes and being reciprocably telescopically separable and interengageable with the two guide means of said other shoe to preclude any relative movement between said shoes in a direction transverse to the direction of reciprocation; a tool-aligning stripper plate means comprising a plurality of identical fiatwise abutting sheet metal plates having aligned apertures for effecting alignment of the tools, and each of said identical plates having at least one pair of locator apertures remote from each tool-aligning aperture therein and aligned with those of the other of said identical plates; reciprocable annular clamping means extending through said aligned locator apertures and holding said identical plates together, said clamping means being slidably disposed on the telescopically separable and interengageable guide means of one of said shoes and movable both jointly with and relatively to said one shoe in a punching operation; and stripping spring means urging said plate means in a direction away from said one shoe to a position defined by coaction between said annular clamping means and said guide means.

7. In a punch and die assembly for punching a workpiece, the combination comprising: two pairs of mutually fiatwise spaced tool-aligning sheet-metal plate means disposed to receive the workpiece substantially parallel to and intermediate said pairs, the upper of said pairs of plate means being reciprocable with respect to the lower pair, and the plate means of said upper pair being also reciprocable with respect to each other, each of said plate means having a group of apertures identical in arrangement to the other, said group including in each of said plate means at least two locator apertures remote from any tool-aligning aperture therein and identical in size to those of the other of said plate means, and also a tool aperture coaxially aligned with a corresponding aperture in the other of said plate means; alignment means extending through said locator apertures and operative to support said plate means independently of each other and to maintain said coaxial alignment; and a removable tool assembly including a die button, a die support slidably receiving said die button and disposed between the plate means of said lower pair, a punch supported by the uppermost one of said plate means and having a bit for cooperation with said die button, and a guide button slidably receiving said bit; said punch, said guide button, said die button, and said die support having peripheral configurations respectively closely slidably received in said aligned tool apertures of said two pairs of plate means in direct peripheral engagement with 10- the respective plate means to preclude relative lateral movement between said tool assembly and said plate means.

8. In a punch and die assembly, the combination comprising: a pair of tool-aligning sheet-metal plate means supported in fiatwise vertically spaced fixed relation to each other, each of said plate means having a laterally elongated aperture aligned with the punch; a pair of vertically elongated die supports each having a generally U-shaped section, such section being parallel to said plate means, each of said die supports having opposite ends respectively extending through the elongated apertures of said plate means and aligned thereby; said die supports being respectively disposed at opposite ends of said elongated apertures with the open end of one U-shape being directed toward the open end of the other U-shape; and a die element removably received and supported by said die supports and extending into said U-shapes for alignment thereby in cooperating relationship with the punch.

9. In a punch and die assembly for punching a workpiece, the combination comprising: an upper sheet-metal plate means and a deflectable lower sheet-metal plate means slidably supported in fiatwise spaced relation thereto for reciprocation with respect to said upper plate means, each of said plate means having an aperture aligned with the die; separate punch guide means having an upper end extending through the aperture of said upper plate means and aligned thereby; other separate punch guide means having a lower end extending through the aperture of said lower plate means and aligned thereby; a punch element; each of said punch guide means having a recess for removably receiving and guiding said punch element in alignment with the die in cooperating relationship therewith; said first named punch guide means supporting said punch element for joint movement, and said other punch guide means having a sliding fit with said punch element; and stripping spring means acting between said separate and said other punch guide means, said lower plate means being yieldably engageable with the workpiece to slide with respect to said upper plate means to load said stripping spring means independently of said deflectable lower sheet-metal plate means for subsequently stripping the workpiece from said punch element.

10. In a punch and die assembly for punching a workpiece, the combination comprising: an upper sheet-metal plate means and a lower sheet-metal plate means slidably supported in fiatwise spaced relation thereto for reciprocation with respect to said upper plate means, each of said plate means having a laterally elongated aperture aligned with the die; a first pair of punch guides each having a generally U-shaped section, and each of said punch guides having an upper end extending through the elongated aperture of said upper plate means and aligned thereby; a second separate pair of punch guides each having a generally Ushaped section, and each having a lower end extending through the elongated aperture of said lower plate means and aligned thereby; said punch guides being respectively disposed at opposite ends of said elongated aperture with the open end of one U-shape being directed toward the open end of the other U-shape; a punch element removably received by said punch guides in alignment with the die in cooperating relationship therewith, and extending into said U-shapes; said first pair of punch guides supporting said punch element for joint movement, and said second pair of punch guides having a sliding fit with said punch element; and stripping spring means acting on said second pair of punch guides, said lower plate means being yieldably engageable with the workpiece to slide with respect to said upper plate means to load said stripping spring means and for stripping the workpiece from said punch element.

11. In a punch and die assembly, the combination comprising: a pair of fiatwise vertically spaced separable tool-aligning sheet-metal plate means, each of said plate means having an aperture aligned with the punch; re-

movable means supporting said plate means in fixed relation to each other independently of each other; a die element; elongated die support means having opposite ends extending through said apertures of said plate means and aligned thereby, said die support means having a first recess extending transversely through said plate means and removably receiving and supporting said die element in cooperating alignment with the punch, and a second recess extending past said first recess and offset therefrom and extending generally parallel to said plate means; and a workpiece stop laterally offset from said die element and having a mounting arm extending generally toward said die element and generally parallel to said plate means, and adjustably received and supported in said second recess.

12. In a punch and die assembly for punching a workpiece, the combination comprising: a pair of horizontal tool-aligning sheet-metal plate means adapted to receive the workpiece at the upper side of said pair in substantially parallel relation thereto, each of said plate means having a group of apertures coaxially aligned with the apertures of the other of said plate means; means removably securing said plate means in fixed spaced parallel relation to each other; and a workpiece guide pin having a lower end freely slidably received in and aligned by 25 the lower of said plate means, and an upper end of re- 12 duced cross-sectional area snugly but freely slidably extending through and positioned by the upper of said plate means, said upper end extending upwardly of the upper surface of said plate means for engaging and laterally guiding the workpiece.

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