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Publication numberUS3871206 A
Publication typeGrant
Publication dateMar 18, 1975
Filing dateAug 29, 1973
Priority dateAug 29, 1972
Also published asCA995176A1, DE2343167A1
Publication numberUS 3871206 A, US 3871206A, US-A-3871206, US3871206 A, US3871206A
InventorsKanehisa Takashi, Nakamura Akio, Otoda Ichizo, Taki Yasuo, Yokozeki Makoto
Original AssigneeMatsushita Electric Ind Co Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Continuous rotary press
US 3871206 A
Abstract
A continuous rotary press is disclosed which essentially comprises a rotary turret rotatable about a drive shaft, a pair of cam grooves stationarily held in position by a press bench and a plurality of dies and the corresponding number of punches cooperative with the respective dies. The dies and punches are radially outwardly slidably carried by the rotary turret and successively move, guided by the respective cam grooves, toward and away from each other during rotation of the rotary turret thereby performing press work.
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United States Patent Otoda et al.

[ CONTINUOUS ROTARY PRESS [75] Inventors: Ichizo Otoda, Hyogo; Akio Nakamura, Kyoto; Takashi Kanehisa, Kyoto; Yasuo Taki, Kyoto; Makoto Yokozeki, Kyoto, all p of Japan [73] Assignee: Matsushita Electric Industrial Co.,

Ltd., Osaka, Japan [22] Filed: Aug. 29, 1973 211 Appl. No.: 392,465

[30] Foreign Application Priority Data Aug. 29, 1973 Japan 48-86926 Aug. 4, 1973 Japan 48-87828 Aug. 16, 1973 Japan 48-921181 Aug. 16, 1973 Japan 48-92ll82 Aug. 16, l973 Japan 48-921183 Aug. 16, 1973 Japan 48-921184 Aug. 16,1973 Japan ..48-921185 Aug. 16, l973 Japan 48-921186 Aug. 16, 1973 Japan 48-921187 [52] U.S. Cl. 72/190, 72/406 [51] Int. Cl B21d 22/08 Mar. 18, 1975 [58] Field of Search 72/184, 185, 187, 190, 72/406 [56] References Cited UNITED STATES PATENTS 2,872,887 2/1959 Praturlon 72/406 Primary Examiner-Lowell A. Larson Attorney, Agent, or Firm-Wenderoth, Lind & Ponack [57] ABSTRACT A continuous rotary press is disclosed which essentially comprises a rotary turret rotatable about a drive shaft, a pair of cam grooves stationarily held in position by a press bench and a plurality of dies and the corresponding number of punches cooperative with the respective dies. The dies and punches are radially outwardly slidably carried by the rotary turret and successively move, guided by the respective cam grooves, toward and away from each other during rotation of the rotary turret thereby performing press work.

24 Claims, 43 Drawing Figures SHEET USUF 15 Fig.6

28302927l9l9d SHEET llUF 15 3 3 we 3 no .5

ovm NQ g CONTINUOUS ROTARY PRESS The present invention generally relates to a press machine and, more particularly, to a continuous rotary press wherein a plurality of radially arranged sets of dies and punches travel in a circular path and, during each travel through 360, successively perform any one of such press work as blanking, perforating, forming, drawing, ironing, trimming and so on while the strip stock to be processed thereby is continuously fed between the dies and the punches with no interruption in the advance of the strip stock even during the performance of the press work.

In general, most press machines are capable of varied types of work. In other words, a press in itself is not sufficient as a production machine, but must be provided with dies and punches in cooperation with the dies and, by suitably selecting the proper dies and punches, it can be designed for a certain specific operation. In view of the fact, press machines heretofore available are classitied in various ways, e.g., according to the design of frame, according to the method of power-transmission, and according to the purpose of press.

The press machine herein disclosed and according to the present invention is, however, termed as continuous rotary press in view of the fact that the strip stock to be processed is continuously fed with no interruption in the advance thereof on one hand and, on the other hand, press work is successively performed by the dies and the counteracting punches in one press machine. This may be possibly classified according to the overall function of the press. This concept of the present invention is claimed to be novel and, therefore, it should be considered the original version of this type of press machine.

So far as the production capacity and the continuous supply of thestrip stock are both concerned, a press machine called 'a nonstop press has been recently developed. Unlike most conventional presses, this nonstop press does not employ a clutch or brake mechanism which must be otherwise serviced frequently because of the repetitive loading and unloading which they undergo. In addition, the nonstop press effectively avoids repetitive severe shock loads on crank shafts and their bearings, so that maintenance is reduced considerably.

Structurally, this nonstop press essentially comprises a so-called floating frame carrying dies thereon. The floating frame is designed so as to move reciprocately in the opposite direction parallel to the direction of advance of the strip stock in one complete cycle of operation. Although the nonstop press has such advantages as mentioned above, the production capacity is limited. This is due to the fact that the reciprocal movement of the floating frame itself, which is relatively heavy, at a relatively high spaced substantially equal to the speed of supply or advance of the strip stock tends to produce a great inertia force and, therefore, the higher the speed of supply of the strip stock, the more difficult it is to synchronize the speed of movement of the floating frame with the speed of supply of the strip stock.

Accordingly, an essential object of the present invention is to provide a continuous rotary press capable of rapid production with substantial elimination of the disadvantages and inconveniences inherent in the conventional press machine.

Another important object of the present invention is to provide a continuous rotary press of the type above referred to, wherein press work is successively performed while the strip stock to be processed thereby is continuously fed with no interruption in the advance thereof, and which does not require any clutch or brake action and cranking mechanisms and their associated bearings.

A further object of the present invention is to provide a continuous rotary press of the type above referred to, of which each cycle of operation is smoothly performed without substantially imposing repetitive and/or successive severe shock on any part of the press, so that no noisy vibration is generated and so that maintenance is considerably reduced.

A still further object of the present invention is to provide a continuous rotary press of the type above referred to, which can be manufactured at reasonable cost in an extremely compact size for a press having a comparable production capacity and which does not, therefore, require a relatively large space for installation thereof.

It is a related object of the present invention to provide a system which is composed of a plurality of continuous rotary presses each being of the type above referred to for making a press line by which blanking, drawing, ironing and trimming are sequentially performed.

According to the present invention, a continuous rotary press machine essentially comprises a plurality of die units and the corresponding number of punch units cooperative with the respective die units. The die units and the punch units are radially outwardly slidably carried by a rotary turret. Relative sliding movement of these die and punch units in the radially outward directions toward to and away from each other is effected during rotation of the rotary turret through respective cam arrangements which efficiently and effectively guide the relative sliding movement thereof. A strip stock to be pressed thereby is continuously fed thereto without interruption in its advance during the performance of the press work.

The turret can be rotated at a relatively high speed, for example, more than rpm, and the machine of the present invention can be capable of rapid production, since the actual time of operation is only the time necessary for the rotary turret to rotate through an angle which is substantially equal to the quotient of the angle of each rotationof the turret divided by the number of the pairs of the die and punch units if a single set of die and punch are respectively provided in the die unit and punch unit.

These and other objects and features of the present invention will become apparent from the following description taken in conjunction with preferred embodiments thereof with reference to the accompanying drawings, in which;

FIG. 1 illustrate how a plurality of cup-shaped cylinders areformed by the press machine of the present invention from a continuous strip material, wherein FIG. 1A is a top plan view of a portion of the strip material, FIG. 1B is a top plan view of a portion of the strip material after having been subjected to a blanking operation, FIG. 1C is a side sectional view ofa portion of the strip material after having been subjected to a drawing operation, FIG. 1D is a side sectional view of a portion of the strip material after having been subjected to an ironing operation and FIG. IE is a side sectional view of a portion of the strip material after having been subjected to a trimming operation,

FIG. 2 is a perspective view of a continuous rotary press according to the present invention showing an outer appearance thereof,

FIG. 3 is a front view of FIG. 2,

FIG. 4 is a top plan view of the continuous rotary press machine of FIG. 2,

FIG. 5 is a longitudinal sectional view of the continuous rotary press machine,

FIG. 6 is a longitudinal sectional view of an essential portion of the press machine,

FIG. 7 is a longitudinal sectional view of each one of die and punch units, showing the details thereof,

FIG. 8 is a front elevational view of a portion of the press machine, showing only two of the radially outwardly arranged die and punch units with respect to the axis of rotation of a drive shaft,

FIG. 9 is a perspective view of stripper plates employed in the press machine,

FIG. 10 is a longitudinal sectional view, on an en larged scale, of a portion of FIG. 6, showing a manner by which a cam follower is engaged in a cam groove,

FIG. 11 is a cross sectional view taken along the line XIXl in FIG. 5,

FIG. 12 is a cross sectional view taken along the line XllXll in FIG. 5,

FIG. 13 is a cross sectional view taken along the line XIIIXIII in FIG. 11,

FIG. 14 a schematic diagram showing a clutch operating mechanism employed in the press machine of the present invention,

FIG. 15 is a side sectional view of the clutch operating mechanism of FIG. 14,

FIG. 16 is a front elevational view of a tensioning unit employed in the press machine of the present invention,

FIG. 17 is a cross sectional view taken along the line XVII-XVII in FIG. 16,

FIG. 18 is a cross sectional view taken along the line XVIIIXVIII in FIG. 17,

FIG. 19 is a front elevational view ofa guide, unit employed in the press machine of the present invention,

FIG. 20 is a side elevational view of FIG. 19,

FIG. 21 is a front elevational view of a take-up unit employed in the press machine of the present invention,

FIG. 22 is a cross sectional view taken along the line XXII-XXII in FIG. 21,

FIG. 23 is a longitudinal sectional view of an intermediate transmission mechanism for transmitting a rotational power of a motor to the take-up unit, which'is employed in the press machine of the present invention,

FIG. 24 is a similar view of FIG. 6, but differ therefrom in that the die unit is provided with a strip stock depressor while the machine itself is designed to perform a trimming operation,

FIG. 25 is a longitudinal sectional view, on an enlarged scale, of an essential portion of FIG. 25,

FIG. 26 is a longitudinal sectional view of a die and punch arrangement according to another embodiment of the present invention,

FIG. 27 is a longitudinal sectional view of the press machine wherein a different type of positioning unit is provided,

FIG. 29 is a diagram showing an arrangement of cam grooves employed in the press machine of the present invention, which are intended for drawing operation,

FIG. 30 is a chart showing respective traces of dies and punches during rotation of the turret according to the cam groove arrangement of FIG. 29,

FIG. 31 is a diagram showing relative positions of the die and punch units resulting from the cam groove arrangement of FIG'. 29,

FIG. 32 is a diagram showing an arrangement of cam grooves employed in the press machine of the present invention, which are intended for ironing operation,

FIG. 33 is a chart showing respective traces of dies and punches during rotation of the turret according to the cam groove arrangement of FIG. 32,

FIG. 34 is a diagram showing relative positions of the die and punch units resulting from the cam groove arrangement of FIG. 32,

FIG. 35 is a diagram showing an arrangement of cam grooves employed in the press machine of the present invention, which are intended for trimming operation,

FIG. 36 is a chart showing respective trace of dies and punches during rotation of the turret according to the cam groove arrangement of FIG. 35,

FIG. 37 is a diagram showing relative positions of the die and punch units resulting from the cam groove arrangement of FIG. 35,

FIG. 38 is a schematic diagram showing a press line composed of a plurality of continuous rotary machines each constructed according to the present invention, and

FIG. 39 is a schematic perspective diagram showing the press line composed of a plurality of the press machines which are housed in respective housing structures.

Before the description of the present invention proceeds, it is to be noted that like parts are designated by like reference numerals throughout the accompanying drawings. It is also to be noted that, although a continuous rotary press according to the present invention can be better adapted to perform any of the various types of press work depending upon the type of dies and punches employed, the description of the present invention will be, so far as the general structural features of the continuous rotary press are concerned, made for the sake of clarification in connection with the rotary press equipped with dies and punches specifically designed for the drawing operation.

However, FIG. 1 illustrates how finished cupshaped cylinders, shown by 5 in FIG. 1E and each satisfying the desired dimensional requirements, are formed from a continuous strip material shown by l in FIG. 1A. In order to sequentially perform different processes represented by FIG. IE to FIG. 1E, i.e., punching, drawing, ironing and trimming, respectively, four continuous rotary presses are required which may be of the same.

construction, but must be equipped with different types of dies and punches specifically designed for these processes. This fact is well understood by those skilled in the art.

Referring still to FIG. 1, so far as production of cupshaped cylinders 5 is concerned, employment of the punching process represented by FIG. 1B is recommended by the reason well understood by those skilled in the art, though it may be omitted regardless of whatever type of press is used. In any event, if employed, the punching process is intended to form equidistantly spaced bases 2, each having a substantial shape similar to the cross section of the finished cupshaped cylinder 5 and linked by a pair of bridges 3 which have been the opposed lengthwise edges of the strip material 1, said bases 2 being naturally situated between each pair of adjacent punched openings 4. The strip material thus shaped as shown in FIG. IE will be, for the sake of convenience, referred to as a strip stock.

The drawing process represented in FIG. 1C is preferably employed for pre-fabricating cups 5a to prevent stresses from exceeding the elastic limit strength of the metal, i.e., the stock, which may otherwise result in a development of cracks in the strip stock. Excess of the stresses over the elastic limit strength of the metal is particularly considerable if each cup-shaped cylinder having a substantial length is to be produced as shown in FIG. 1D or E. This is true of the press work performed by any type of other presses than that of the present invention. It is to be noted that the only difference between the drawing and the ironing results from employment of different types of dies and punches while the press machines for these processes remain the same.

Ironing and trimming operations may be both performed on one continuous rotary press if a particular type of die and punch designed to iron and trim the cupshaped cylinders 5a and 5 simultaneously, are employed.

From the foregoing, it will be clearly understood by those skilled in the art that the continuous rotary press machine according to the present invention has such a versatility as to make it possible to use the same press for many different jobs and operations.

As regards the details of the continuous rotary press according to the present invention, reference is first made to FIGS. 2 to 8. The continuous rotary press machine constructed according to the present invention essentially comprises a substantially circular framework which may be integrally formed with a press bench 11 by a metal casting technique. The circular framework 10 is integrally formed with an annular flanged portion 10a frontwardly projecting therefrom at right angles to the plane of the framework 10. This framework 10 is also formed at a substantially central portion with an opening which supports a turret 12 and a drive shaft 13 in such a manner as will be hereinafter described.

The turret 12 has a substantially funnel-shaped cross section as shown in FIG. 5 and is integrally formed with a stem 12a which loosely extends through the opening of the framework 10. This turret 12 is rigidly mounted on the drive shaft 13 with the stem 12a rigidly connected thereto, for example, by means of a key-groove engagement or by the use of one or more set pins, so that said turret 12 can rotate together with the drive shaft 13. As best shown in FIGS. 5 and 6, a ball bearing 14 of a type composed of a plurality of balls and a pair of outer and inner rings 14a and 14b with said balls rollably situated therebetween is mounted on the stem 12a of the turret 12 at the central opening of the framework 10 for facilitating a smooth rotation of the turret 12 relative to the framework 10. This ball bearing 14 is secured in position in such a manner that bolts are tapped into the framework 10 as at 15 through a radially outwardly extending flange, integrally formed with the outer ring 140, while a set ring 16 is threaded to a free.

end of the stern so as to avoid a possible displacement of the inner ring 14b.

The turret 12 is formed as at 17 with a plurality of pairs of first slide bores radially outwardly extending at right angles to the longitudinal axis of the drive shaft 13 and is also formed as at 18 with the corresponding number of second slide bores situated backwardly of said individual pairs of first slide bores 17 and in parallel to the latter and similarly radially outwardly extending at right angles to the longitudinal axis of the drive shaft 13. As best shown in FIG. 6, each of the first slide bores 17 and each of the second slide bores 18 are both provided with bushings 17a and 18a, respectively, which are non-detachably inserted in said slide bores 17 and 18.

An annular cam plate 19 having a cam groove 19a formed therein of a configuration as will be described later is rigidly, or otherwise integrally, secured to the annular flanged portion 10a of the framework 10. Similarly, another annular cam plate of a smaller size than the cam plate 19, which has a cam groove 20a formed therein of a configuration as will be described later, is supported by the framework 10 through a positioning unit 21 of a construction as will be described later.

In the above construction, the continuous rotary press machine further comprises die units and punch units, each being provided in a number of substantially equal to the number of pairs of the first slide bores 17 or the number of the second slide bores 18. Because these die units and these punch units are individually of the same construction, only one each of the die units and the punch units will be described for the sake of facilitating a better understanding thereof.

Each die unit and the punch unit associated there with are best shown in FIGS. 6 to 8 and generally indicated by 22 and 23, respectively.

The die unit 22 comprises a pair of shanks 24 slidably extending through the bushings 17a in said first slide bores 17, respectively, in parallel and spaced relation with respect to each other. Individual first ends of these shanks 24 are rigidly connected by set pins 25 with a bracket 26 which carries an eccentric cam follower 27 in a manner as hereinafter described. With particular reference to FIG. 10, a shaft 28 extends through the bracket 26 and has one end eccentrically mounted, or otherwise integrally formed, with said cam follower 27 with a spacer or washer 29 interposed between said bracket 26 and said cam follower 27. The other end of the shaft 28 is threaded to receive a nut 30 rigidly screwed thereto. It is to be noted that, although the cam follower 27 slidably engages in the cam groove 19a of the cam plate 1 9 without rotating about the longitudinal axis of the shaft 28, this eccentrical mounting of the cam follower 27 on the shaft 28 permits the relative position of the die unit 22 with respect tothe associated punch unit 23 to be finely adjusted during the course of assembly of the press machine. However, this eccentrical mounting is not always necessary and the cam follower 27 may be in the form of a roller coaxially rotatably mounted on the shaft 28.

The second individual ends of the shanks 24 opposed to the above mentioned first ends thereof are connected to each other by and mounted with a spacer block 31 formed with an opening as at 310. For this purpose, a pair of bolts, generally indicated by 32, extend through said spacer block 31 and are then tapped into the respective shanks 24 as best shown in FIG. 6.

Secured to the spacer block 31 by means of a plurality of bolts 33 is a carriage 34, the details of which are best shown in FIG. 7. As shown, this carriage 33 is formed with a pair of guide holes 34a and also with a pair of recesses 34b of circular cross section situated on one end face thereof adjacent to the shanks 24. This carriage 34 is also formed with through holes 34c respectively in alignment with said recesses 34b. A die holder 35 having longitudinally extending holes 35a formed therein and sleeve-shaped dies 36 respectively non-detachably inserted in said holes 35a is secured to the carriage 34, with the dies 36 aligned respectively with the through holes 340, by the use of bolts 37 which extend through the carriage 34 and are then tapped into the die holder 35. For facilitating positioning of the die holder 35 relative to the carriage 34 prior to screwing of the bolts 37 and/or during replacement of the dies 36 of different types, one or more alignment pins 38, each having one end pressure fitted into either the carriage 34 or the die holder 35 and the other end engaged into the holder 35 or the carriage 34, are provided.

The recesses 34b in the carriage 34 are closed by individual caps 39 mounted on the other end face of said carriage 34 by the use of, for example, set screws (not shown). Knock-out pins 40 each having a flat land 40a integrally formed therewith slidably extend through the holes 340 and then the dies 36 while the flat lands 40a thereof are situated within the recesses 34b. These knock-out pins 40 are biased towards the punch units 23 with the respective flat lands 40a resting on the bottoms of these recesses 34b by the action of compression springs 41 each interposed between the cap 39 and the flat land 40a of the knock-out pin 40, and within the recesses 34b, respectively. As will become clear, each knock-out pin 40 acts to eject a drawn cup on the strip stock to avoid a possible clog of the corresponding die 36.

Still with particular reference to FIGS. to 8, each punch unit 23 comprises a carriage 42 of substantially L-shape as shown, which carries guide posts 43 pressure fitted thereto for sliding engagement in the respective guide holes 34a in the die carriage 34 during relative motion of these die and punch units 22 and 23, as will be described later, so as to guide this relative motion. As best shown in FIG. 6, this punch carriage 42 is rigidly secured to a sliding block 44 by a bolt 45 extending therethrough and tapped into said sliding block 44. An alignment member 46 having one end tapped into the sliding block 44 and the other end slidingly engaged in a guide groove formed in said block 44 as at 44a is provided for avoiding an arbitrary pivot of the block 44 about the axis of the bolt 45. The sliding block 44 thus carrying the punch carriage 42 is positioned so as to be backed up by the turret 12 with the intervention of a plate member rigidly secured as at 47 to the turret 12 by a plurality of set screws 48 tapped into the turret 12, thereby to provide no substantial frictional resistance to the movement of the sliding block 44. If that portion of the turret 12 where the plate member 47 contacts is polished to provide a smooth surface, the plate member 47 that has been described as employed in this instance may be, of course, omitted. This sliding block 44 is rigidly connected through a shank 49 with a cam follower 50, slidably engaged in the cam groove 20a in the cam plate 20, in a manner as will be now described.

The shank 49 is connected with the sliding block 44 in any suitable method and, in the instance as shown, has one end inserted in said block 44 and is then held in position by a set pin 51 extending through the block 44 across said shank 49, a substantially intermediate portion of which slidably extends through the bushing 18a within the second slide bore 18 in the turret 12. The other end of said shank 49 is mounted with a substantially L-shaped bracket 52 carrying said cam follower 50, said bracket 52 being rigidly secured thereto by a nut 55 fastened to the end extremity of said shank 49. Mounting of the cam follower relative to the bracket 52 is substantially the same as that of the cam follower 27 relative to the bracket 26 and, therefore, will not be described for the sake of brevity.

It is to be noted, however, that the plate member 47 may be in the form of an annular ring plate common to all the blocks 44 of the radially arranged, individual punch units 22 as shown in FIGS. 2 and 3.

Each carriage 42 of the punch units 22 is, as best shown in FIG. 7, mounted with a pair of punches 54 in position to respectively align with the dies 36. A punch holder 55 is rigidly mounted on the carriage 42 by a plurality of bolts 56 so that these punches 54 are held in position in respective alignment with the dies 36 and to substantially extend at right angles to the longitudinal axis of the drive shaft 13. It is to be noted that, in the instance as shown, the punches 54 are shown in the form of drawing punches for use in drawing operation. However, when trimming punches are to be used, replacement can be easily performed merely by undoing the bolts 56.

The punch unit 23 further comprises a polygonally shaped block 57 having flat flanks 57a in a number corresponding to the number of the die units 22, for example, l2 flat flanks in the instance as shown in FIGS. 2 and 3. This polygonally shaped block 57 is rigidly mounted on the shaft 13 for rotation together with said drive shaft 13 in such a way that the flanks 57a face towards the respective die units 22. Mounting of the plolygonal block 57 on the drive shaft 13 is preferably carried out by a key and groove engagement (not shown) and a fastening nut 58 is used for avoiding separation of the block 57 from the drive shaft 13.

Stripper plates 59, each having guide openings formed as at 59a and sleeves 60, non-detachably inserted respectively in said guide openings 59a are rigidly mounted on the flat flanks 57a of the block 57 by means of a plurality of set bolts, extending therethrough and tapped into the block 57 as at 61, with each pair of the sleeves 60 in alignment with and in spaced relation to the punches 54 carried by the associated carriage 42. As shown in FIGS. 8 and 9, each of the stripper plates 59 is so shaped that the outer appearance of the arrangement of these plates 59 mounted on the block 57 represents an contour similar to the polygonal shape of said block 57.

As best shown in FIGS. 7 and 9, each stripper plate 59 may be provided, as at 62, with a pair of positioning pieces extending in equidistantly spaced relation to each other on both sides of an imaginary line passing through the centers of the sleeves 60. These positioning pieces 62, if employed, act to avoid displacement of the strip stock with respect to the direction of advance of said strip stock. In addition, a locating piece 63 may be,

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2872887 *Mar 2, 1954Feb 10, 1959Joseph PraturlonRotary press comprising a plurality of tool groups
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5350373 *Oct 9, 1992Sep 27, 1994United States Surgical CorporationApparatus for attaching surgical suture components
US5462543 *Jun 9, 1994Oct 31, 1995United States Surgical CorporationApparatus for attaching surgical suture components
Classifications
U.S. Classification72/190, 72/406
International ClassificationB21D51/00, B21D28/12, B21D51/10, B21D24/00, B21D28/10, B21D28/02
Cooperative ClassificationB21D51/10, B21D28/10, B21D28/12, B21D24/00
European ClassificationB21D28/12, B21D24/00, B21D51/10, B21D28/10