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Publication numberUS2394346 A
Publication typeGrant
Publication dateFeb 5, 1946
Filing dateSep 28, 1944
Priority dateSep 28, 1944
Publication numberUS 2394346 A, US 2394346A, US-A-2394346, US2394346 A, US2394346A
InventorsWiedman Edward L
Original AssigneeWiedman Edward L
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Punch and die mechanism
US 2394346 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

Feb. 5, 146. E M N 2,394,346

PUNCH AND DIE MECHANISM Filed Sept. 28, 1944 2 Sheets-Sheet I Patented Feb. 5, 1946 UNITED STATES PATENT OFFICE PUNCH AND DIE MECHANISM Edward L. Wiedman, Tonawanda, N. Y.

Application September 28, 1944, Serial No. 556,229

13 Claims.

My invention relates to a punch and die device and more particularly to one designed for individually and speedily punching holes accurately centered and disposed center to center under-a predetermined plan or arrangement.

In the use of my invention I employ atemplate having pilot holes spaced or arranged center to center according to a predetermined plan and in conformity with which a sheet metal part or other sheet material is to be perforated.

One of the objects of my invention is to provide a punch and die device particularly designed for use in connection with a template having a pilot hole and wherewith a hole can be punched in a sheet metal or similar part against which the template is placed with assurance that the hole so punched will be coaxial with the pilot hole in the template.

Another object of my invention is to provide a punch and die device wherewith a sheet metal or similar part can be quickly and accurately punched or perforated with assurance that the holes punched therein will be accurately centered and spaced apart center to center, using a template in conjunction therewith having pilot holes therein, according to which the sheet metal part to be operated upon will be provided with holes smaller than the pilot holes in the template, but which will be centered in exact accordance with said pilot holes.

Another object of my invention is to provide a punch and die device of the kind mentioned, wherewith a sheet metal part having a template clamped or otherwise temporarily held thereagainst and provided with pilot holes, will be punched with correspondingly centered holes of smaller diameter.

A further object of my invention is to provide a punch and die device wherein the punch memoer is provided with an interchangeable pilot element and an interchangeable punch, and wherein the die member is provided with an interchange-v able die so that all remaining parts of the punch and die members can be used for punching varions-sized holes, while permitting the pilot element to be changed to conform in diameter to the diameter of the pilot holes in the template and the punch to conform to the diameter of the holes to be punched in the stock or work-piece to be operated upon.

A further object of my invention is to provide a punch and die device equipped with a'pilot ele ment used in conjunction with a template havin pilot holes, and a power-actuated punch designed to successively perforate or. punch holes under quick progression in a sheet metal part or other -work-.piece according to the pilot holes in the template.

A still further object of my invention is to provide a punch and die device which can be applied to a conventional type of riveting machine, punch press, or any other machine or apparatus enabling the on member to be fixedly attached thereto and having a power-actuated part to which the punch member may be attached and wherewith a sheet metal part or other work piece can be quickly passed between the punch and die members in conjunction with a template. and holes punched successively through the work piece in exact accordance with pilot holes formed in the template.-

With the above and other objects in view to appear hereinafter, my invention consists in the construction, arrangement, and combination of parts to be hereinafter described, and more particularly pointed out in the subjoined claims.

In the drawings:

Fig. 1 is a view of a converted riveting machine to which my improved punch and die device is applied, having replaced th usual co-acting parts of a riveting device used in the manner-of the application of the two co-acting parts of my d es vice.

Fig. 2 is a side elevation of my improved punch and die device, showing the two members thereof detached from their supports, but arranged relatively as they are used for co-action.

Fig. 3 is a central longitudinal section through the punch member of my device.

Fig. 4 is a cross-section taken on line 44, Fig. 3. v

Fig. 5 is a cross-section taken on line 5-5, Fig. 3.

Fig. 6 is a top plan view of the die member of my device.

Fig. 7 is a vertical section through the die member of my device, shown in association with the punch head of the punch member, the latter being shown in elevation and the section of the die member being taken on line 1-1, Fig. 9.

Fig. 8 is a side elevation of the die member, viewed from the right or left as shown in Fig. '7.

Fig. 9 is a horizontal section taken online 8-8, Fig. '7. Fig. 10 is a horizontal section taken on line Iii-l0, Fig, 7. v

Fig, 11 is a section similar to Fig. '7, showing the punch. member lowered with. the pilot el m nt thereof entered in a pilot opening in. the tem late and the work piece perforated by the punch, the

vided and under which arrangement the die member has preferably a fixed location and the punch member is reciprocally-arranged for movement toward and from the die member.

In the exemplification of my invention, shown in the drawings, my punch and die mechanism is attached to a. riveting machine It, having a bed or table 16 and a horn l1 overhanging said bed or table and spaced a considerable distance therefrom.

' In riveting machines of this generaltype, a ver-' tically reciprocating element I8 is located in the nose of thehorn IT and, projects downwardly therefrom and-to this reciprocating element, the punch member I3 of my improved punch and die device is secured. This punch member is designed for coaction with the die member 23, which is rigidly secured in the bed or table 15 of the riveting machine. V

Machines of this kind are'equipped with controls, which include foot'operated switches or other means whereby the reciprocating element I8' is, caused to actuate. under manual control. Since theriveting machine forms no partof this invention, it is believed unnecessary to illustrate and describe the control means by means of which the machine is operated and therefore two parts, whether they form parts of a riveting machine or parts of any other machine, device or apparatus, which are relatively movable toward and from each other, may serve as supports for the two members of my punch and die device.

@The die'device comprises a body portion 2!, preferably constructed of two comparatively thick plates 22, 23, separated by spacing pieces 24.. While this body portion may vary in outline, I have shown it square in shape, with the spac ing-pieces 24 ranging along opposite marginal portions of the plates. spacing-pieces 24 are connected together in any approved manner, but I have shown screws 25 passed through the plate 23 and spacingpieces 2 and threaded into the plate 22, as best shown in Fig. 12; each screw having a cylindrical head countersunk into the plate 23and providedwith a polygonal socket into which a suitable wrench may be 'fitted for removing the screw or for threading it into place. Any other means for securing the parts together may, of course, be employed.

Centrally in the upper plate 22 is a die 26 provided with'a' punch-hole 21. This die is interchangeable with other dies having punch-holes of varying diameters or of difierent outline. The upper plate 22 of the die member is provided with a screw-threaded openin into which the shank 28'of thedie is threaded. The punch-hole 2?, which is drilled into the die from the top, opens into a bore 29 of larger diameter than the punchhole and the lower end of this bore open into thespace 30 between the plates 22 and 23. This space is open at opposite sides of the die member and thus permits slugs stamped from a workpiece to be blown out or otherwise removed at either of said open sides. A yieldable work sup- The plates 22, 23 and port 3| spans the top of the body portion 2! of the die member and it comprises a plate 32, preferably normally positioned so that its undersurface is in a plane slightly above the upper sur face of the die 26. At opposite sides of this plate there are guides 33 and at the two remaining sides I provide cars 34 which may also serve as guides. The guides 33 and the ears 34 are stamped integral with the plate 32, each guide being of substantially -U -formation,'thus forming two parallel depending arms 35 and a cross-member 35 connecting the lower ends of said arms. The

guides 33 are in slidable contact with opposite sides of the body portion 2! and the arms thereof are provided with vertical slots 3! through which guide-screws 38 are passed and which are threaded into the spacing-pieces 24, as best shown in Figs. 7 and 10.

The guide ears 34 are also adapted to ride i sliding contact with the two remaining sides of the body portion 2| when the work-support 3!, or spring pad as itmay be termed, is depressed and thus absolute vertical movement of the support or pad is assured. The plate 32 is provided centrally with an opening 39 conforming to the outline of the die 26 and slightly large in diameter than said die, so that when the work-support is depressed, the die may enter said opening.

In the lower plate 23 of the body portion, sockets or depressions 40 are'formed and in the upper plate 22 openings 4| are provided, preferably of the same diameter as the sockets. Springs 42 serving to hold the support or pad 3i in itsupperrnost position have their lower ends entered in the sockets 40 and these springs extend upwardly through the openings 4! and bear at their upper ends against the underside of the plate 32 serving as the main portion of said support or pad. The guide screws 38 and the vertical slots 31 through which they are passed, serve to limit the upward movement of the support or pad and when the latter is in normal position, the lower ends of the slots 31 are in contact with said guide screws. It will thus be clear that the springs 42 serve to hold the support or pad in its elevatedi'position, while the screws 38 limit the upwardmovement thereof and the guide slots permit th same to be depressed against th action of the springs 42.

The sockets 40 may be provided with openings 43 at their lower ends so that foreign matter entering the space 30 and lodging in the sockets will find exit through said openings. 44 designates a support for the die member and in the form shown, this support is designed to be applied to the bed or table I 6 of the riveting machine. It is so constructed that it may be substituted for one of the members of the riveting device used in such machines. For this purpose it is provided with a screw-threaded shank 45 at its upper end and a suitable supporting face 45 at the base of the shank to provide a comparatively large bearing for the lower plate of the body portion 2|. At its lower end this support has a screw-threaded shank 47, which is threaded into a screw-threaded opening (not shown) in the bed or table I 6.

It is, of course, understood that this support may be varied in outline and construction, depending on the particular machine or apparatus part'to which it is to be secured, and in some instances may be dispensed with and the body portion 2| fastened directly onto a support. Therefore, the term support" may mean a part attached to the body portion, such of the general type illustrated by the part designated 4'4, or it may be. a part of a machine, device or apparatus onwhich the die member'zl is placed or attached.

The punch member comprises a cylinder or tubular element 48 open at its upper end and closed at its lower end, the lower closed end having a screw-threaded bore 49 axial therein into which is threaded the shank 50 of a punch head 5!, which I more particularly designate a pilot element. This pilot element is provided with an axial opening therethrough and is replaceable with other pilot elements in which the axial openings therein differ in size, for a purpose to appear hereinafter.

Vertically-slidable in the cylinder or tubular element 48 is a plunger 52, which has means at its upper end for attachment to a movable part of a machine, device, or apparatus in a manner that the entire punch member may be reciprocated and, as shown in the drawings, the upper end of this plunger is provided with an outstanding flange 53, from the upper surface of which a, screw-threaded shank 54 extends. This screw-threaded shank may be threaded into a reciprocating part, such as the part l8, shown in Fig. 1 of the drawings, and where the space between such reciprocating part and the bed or table, such as part l5, Fig. 1, is greater than the combined length of the punch and die members plus the length of the stroke of said reciprocating part. an extension fitting 55 is applied to the shank 54' and this comprises a cylindrical part 56 having a screw-threaded shank 51 rising from its upper end and an internally-threaded bore 58 opening to its lower end to receive the shank 54 of the plunger 52. The lower end of the cylindrical part 56 has an outstanding flange 59, preferably conforming in outline to the flange 53 on said plunger and these flanges 5.3 and 59 may be provided with flattened portions at diametrically opposite sides, as shown for one side at 60, Fig 2. The punch head or pilot element 5| may also be provided with flattened portions at opposite sides, as shown at 6|, Figs. 2, '7 and 11. These flat portions are for the application of a wrench or other suitable tool so that the extension or fitting 55 may be securely fastened to the plunger or both fastened in place, and so that the pilot element can be easily removed or applied to the cylinder 48.

It is, of course, understood that where the space between the horn l1 and bed or table It of the machine is restricted from that shown in the drawings, the extension or fitting 55 may be dispensed with.

Integral with the plunger 52 and extending axially downwardly therefrom is a slender plunger pin 62, its lower end terminating well above the inner end of the pilot element 5!, as clearly shown in Fig. 3. Surrounding said pin and bearing at its upper end against the under side of the plunger 52 and at its lower end against the closed lower end of the cylinder 48 is a spiral spring 63. Passed diametrically through the plunger 52 is a stop pin 64. This pin passes through vertical slots 65 in the cylinder 48 at diametrically opposite points and normally this stop pin bears against the upper ends of said slots under the influence of the spring 63. This stop pin also serves to prevent separation of the cylinder 48 from the. plunger 52.

The lower end of the plunger pin 62'is bored out to receive the upper end of a punch 6.6, which extends downwardly into the pilot element 5!.

The punch may have its lower end even with the lower end of the pilot element or it may termi nate slightly above said lower end when the parts are in normal position.

I preferably solder this punch into the plunger pin, silver solder being used for that purpose so that when the punch becomes broken or a punch of a different size is to be used, it may be easily removed by heating the solder used to fasten it to said plunger pin. A pin having a punch of smaller or larger diameter than the bore in the plunger pin necessarily calls for an enlargement or reduction, respectively, of the upper end of the punch and, of course, the pilot element will have to be replaced with another having a bore therethrough conforming to the enlarged or reduced punch.

In the drawings, the work piece is designated by the numeral 61, the template by the numeral 68 and the pilot holes in the template by the numeral 69, as clearly shown in Fig. 11.

The work piece and the template mounted thereon and clamped or otherwise held in a firm manner on the work piece is placed upon the spring pad and advanced toward the operating center of the punch and die device. The reciprocating element ill, or any other part to which the punch member may be secured, is then lowered and simultaneously therewith the spring pad 32 is depressed sufliciently to cause the work piece to rest upon the die 26. At the same time the pilot hole selected for centering the hole to be punched is positioned to cause the pilot element to enter it and when the punch is lowered to its full extent it will have punched the hole in the work-piece co-axial with the pilot hole in the template.

As clearly shown in Fig. 11, the template is provided with any number of pilot holes and these determine the exact centers which the holes to be punched in the work piece are to have while advancing the work piece and the temp-late over the spring pad. It is, of course, understood that the terminal of the pilot element is the exact shape as the pilot hole in the template. Immediately the pilot element is entered in the pilot hole, the lower face of said pilot element is brought in contact with that region of area of the work pieceremaining uncovered by the template. The work piece at such times bears against the upper face of the die and the upper face of the spring pad. When applying my improved punch and die device to a machine of the type shown in the drawings, the reciprocating element 18 is caused to be actuated by an electric control (not shown) or otherwise and this in turn forces the plunger 52 and its punch downwardly, causing the punch end of the latter to pass through the work piece in its act of entering the punch hole in the die, during which action the ends of the stop pin 63 move downward in the slots 65 and the spring 62 is compressed.

The slugs punched from the work piece are delivered into the space 30 in the die member.

During the reverse movement of the reciprocating element l8, thepunch is withdrawn from the die and work piece and the latter advanced with the template thereon to bring another pilot hole 89 in the template into registration with the pilot element, the latter entering the pilot hole and the operation being repeated in the manner described. This is continued for all of the pilot holes in the template so that for each pilot hole in the tem platev a hole is punched co-axially therewith in the work piece in quick progressive order.

tance between the ,punch member-and the upper,

face of the spring pad forming part of the die member may be varied,'but quicker progressive punching action is assured when all lost motion of the moving, parts is dispensed with and the spacing of the male and female members of the punch and die device will be made according to the thickness of the work piece and that of the template associated therewith.

It is, of course, to be understood that various changes can be made in theconstruction and assembly of parts without departing from my invention or sacrificing any of the advantages thereof and that many changes in this respect can be made without departing from the scope of the appended claims.

Having thus claim is: 7 l

1. In combination with two spaced-apart supportsrelatively movable toward andaway from each other, a punch and die device comprising a described my invention what 1' punch member secured to oneof said support and I a die member carried by the other, said punch member having a cylinder, a plunger entered in said cylinder and having non-yielding means for attachment thereof to one of said supports, a spring within said cylinder exerting force against said plunger and cylinder in opposite directions, respectively, a punch axially secured to said plunger within said cylinder and a pilot element applied to the lower end of said cylinder co-axial with said punch and which is adapted to enter a pilot holein a template associated with the work piece to be punched, said punch extending into said pilot element'and adapted to be projected therefrom so as to punch the work piece and said die member having a die into which said punch is to be entered when the work piece is'punched thereby.

2. In combination with two spaced-apart supports relatively movable toward and away from each other, a punch and die device comprising a punch member secured to one of said supports and a die member secured to the other, said punch member having a cylinder, a plunger entered in said cylinder and reciprocable therein, said plunger having means for attachment thereof to one of said supports, a spring within said cylinder serving to retain said plunger at the end of its movement in one direction, means to prevent accidental detachment of said plunger from said cylinder, a punch axially and removably-fastened to said plunger and a pilot element removably secured to the end of said cylinder distant from said plunger and into which said punch is entered, and a die member having yielding supp rt and a die upon which the work piece to be punched receives support after depressing said yielding support under action of said cylinder and on which work piece a template having a pilot hole therein is to be placed, said pilot element being adapted to enter said pilot hole and said punch to punch a hole in the work piece co-axial with and smaller than said pilot hole.

3. In combination with two spaced-apart supports relatively movable toward and away from each other, a punch and die device comprising a punch member securedto one of said support and a die member secured to the other, said punch member comprising a cylinder open at one end and closed at the other and having longitudinallydisposed slots therein at diametrically-opposite points, a plunger entered in the open end of said cylinder and having a stop-pin passed therethrough with opposite ends thereof entered in said slots, a spiral spring hearing at one end against said plunger and at its other end against the wall at the closed end of said cylinder, a pilot element threaded axially into the closed end of said cylinder and interchangeable with other pilot elements and a punch interchangeable with other punchearemovably and axially fastened tosaid plunger within said cylinder and extending axially into said pilot element, said plunger being adapted to be moved inwardly toward the closed end of said cylinder against the action of said spiral spring soas to cause saidpunch to be axially projected from said pilot element, said die member having a die into which said punch is to be entered in the act of punchingan opening through a work piece having a template thereon provided with a pilot opening into which said pilot element is to be entered.

. 4. In a punch and die device, a cylinder open at one end and having a' pilot element axially applied to its other end and adapted to be entered in a pilot hole in a template held against a work piece to be punched, a plunger within said cylinder adapted to be reciprocated therein and having a punch arranged axially with respect to said pilot element and said plunger, means to limit the movement of said plunger within said cylinder in one direction, and a spring interposed between said plunger and the end of the-cylinder havin said pilot element applied thereto, said spring serving to maintain said plunger at the end of its movement in said direction and to yield under movement of said plunger in its opposite direction, said punch being adapted to punch the work piece axially with respect to said pilot element.

5. In a punch and die device, a cylinder open at one end and closed at its other end and having a screw-threaded opening axially in its'closed end, a pilot element having a threaded portion entered in said threaded opening and a free terminal serving as a pilot adapted to enter a pilot hole in a template clamped or otherwise applied to a work piece to be punched, said pilot element having an axial bore therethrough and being replaceable with other pilot elements having axial bores of different diameters and pilot terminals of diiierent sizes or shapes, depending on the pilot hole in the template being used, a plunger reciprocal in said cylinder, and'a punch axially applied to said plunger and entered in the axial bore of said pilot element, said punch being interchangeable with other punche conforming to the axial bore in the pilot element being used.

6. A punch member adapted for punching a work piece according to a pilot hole in a template applied to the work piece, comprising a cylinder open at its upper end and closed at its lower end and having apilot element removably secured in 'said closed lower end, said pilot element having a pilot terminal at its lower end to fit the pilot hole in said template and an axial punch-receiving bore therethrough, said pilot element being interchangeable with other pilot elements having pilot terminals and punch-receiving bores of different sizes or formation, a plungerentered into the upper open end of said cylinder, a spiral spring between the inner end of said plunger and the closed end of said cylinder, means to limit the upward movement of said plunger within said cylinder, and a punch applied axially to the inner end of said plunger adapted for movement in the axial bore of said pilot element and replaceable with other punches so as to conform to the shapes or sizes of the axial bores of other pilot elements being used interchangeably.

'7. In combination with two spaced apart supports relatively movable toward and away from each other, a punch and die device comprising a punch member secured to one of said supports and having a punch, a die member for co-action with said punch member, said die member comprising a body portion, a die carried by said body portion having a punch hole axially alined with said punch, and a spring-sustained depressible pad lying over said body portion and normally held in spaced relation thereto and in a plane above said die, said pad being adapted to have the work piece to be punched placed thereon and having an opening therein into which the die extends when said pad is depressed, and means to limit the upward movement of said pad.

8. In combination with two spaced-apart sup-' ports relatively movable toward and away from each other, a punch and die device comprising a punch member secured to one of said supports and having a punch, a die member for co-action with said punch member, said die member comprising a body portion, a die carried by said body portion having a punch hole axially alined with said punch, a pad normally spaced from the upper face of said body portion guided for vertical movement on the latter, a spring carried by said body Portion and exerting upward pressure against said pad,

and means to limit the upward movement of said pad against the force of said spring, said pad being adapted to have the work piece to be punched placed thereon.

9. In combination with two spaced-apart supports relatively movable toward and away from each other, a punch and die device comprising a punch member secured to one of said supports and a die member for co-action with said punch member, said die member comprising a body portion having a die extending upwardly from said body portion and provided with a punch hole, a plate lying over said.body portion in spaced relation thereto and provided with guide-and-stop means to guide said plate in its movements toward and from said body portion and to limit the upward movement thereof, springs carried by said body portion to normally force said plate upwardly and maintain the same in spaced relation to the upper surface of said body portion and in a plane above said die, said plate having an opening therein co-axial with said die and into which the latter extends when said plate is lowered, said plate being adapted to have the work piece and a superposed template provided with a pilot hole placed thereon, said punch member having a pilot terminal adapted to enter the pilot hole in said template when depressing said plate with the work piece and template thereon, and a punch movable in said punch member and adapted to be projected axially through said pilot terminal when entered in said pilot hole and to punch a hole in th work piece axially with respect to said pilot hole.

10. In a punch and die device, a die member comprising two superposed plates, spacing members connecting said plate together to form a space therebetween, upwardly facing sockets in the lower of said plates, openings co-axial with said sockets in the upper plate, a die removably secured within said upper plate and projecting upwardly therefrom, a spring pad arranged above said upper plate and having depending portions in sliding contact with sides of said body portion, springs passed through the openings in said upper plate and having their lower ends entered in said sockets and their upper ends bearing against the under surface of said pad to urge said pad upwardly, and means for limiting the upward movement of said pad under force of said springs,

' said pad having an opening therein co-axial with said die and into which the upper projecting portion of said die is adapted to extend when pressing said pad downwardly with the work piece to be operated upon thereon.

11. In a punch and die device for punching a hole in a work-piece co-axial with a pilot hole in an associated template held to said work-piece, a member having a pilot element adapted to be selectively entered in the pilot hole in said template and a perforating tool movable axially through said pilot element, a second member provided with a hole to receive said perforating tool, and a spring-pressed support for the Work piece and its associated template yieldable with said two lastmentioned objects to permit said pilot element to be entered in said pilot hole and said work-piece to rest on said second member and to enable said perforating tool to penetrate the work-piece and form a hole therein co-axial with and smaller than said pilot hole.

12. In a punch and die device for punching a hole in a work piece co-axial with a pilot hole in a template lying on said work piece, a punch member having a pilot element adapted to be entered in the pilot hole in said template and a punch movable axially through said pilot element. a die member having a die provided with a punch hole to receive said punch and a yielding support for the work piece and its associated template yieldable with said work piece and template to permit said work piece to bear against said die and to enable said punch to punch a hole in said work piece oo-axial with and smaller than said pilot hole.

13. An assembly adapted to form holes in sheetmetal, comprising a non-yielding body, an element carried by said non-yielding body and having a tool-receiving opening, a yielding support also carried by said non-yielding body and having an opening to receive said element when said support is depressed, said support being adapted to support being adapted to support the work-piece to be operated upon, a template adapted to lie on the work-piece and having a pilot hole larger than the hole to be formed in the work-piece, and a cooperating member having a pilot element adapted to enter the pilot hole in said template and a tool movable through and co-axial with said pilot element adapted to be passed through the work-piece after said pilot element has been entered in the pilot hole of said template so as to form a hole in said work-piece co-axial with the pilot hole in said template.

EDWARD L. .WIEDMAN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2667227 *Jan 12, 1948Jan 26, 1954Isidor B LaskowitzVariable speed counter-rotating rotor system for helicopters and control means therefor
US2715440 *Aug 7, 1951Aug 16, 1955Scovill Manufacturing CoMethod and apparatus for forming openings in woven fabrics
US2827963 *Dec 3, 1954Mar 25, 1958Allith Prouty IncPerforating machine
US2837161 *Apr 14, 1955Jun 3, 1958Wales Strippit CorpPerforating apparatus
US3127044 *Nov 20, 1962Mar 31, 1964BrownOffset
US4012975 *Jul 31, 1975Mar 22, 1977Lalone Barry GrantHigh speed punching apparatus and tool therefor
US4130040 *Aug 23, 1977Dec 19, 1978Amp IncorporatedCutter assembly
US5195413 *Aug 16, 1991Mar 23, 1993Mate Punch & Die Co.Shearing tool for punch presses
USRE29507 *Aug 29, 1973Jan 3, 1978Long-Lok Fasteners CorporationApparatus for forming self locking fasteners
Classifications
U.S. Classification83/387, 83/568, 83/395
International ClassificationB21D28/26, B21D28/24
Cooperative ClassificationB21D28/265
European ClassificationB21D28/26B