EP0140373B1 - Cutting press and tool set for cutting presses - Google Patents

Abstract

Stamping machine with a series of tools having each a matrix and, at a certain interval, a stamp which is displaceable in a guiding sleeve. The guiding sleeves are plugged in interchangeably in a guiding plate. To each tool there is adjoined an engageable and disengageable coupling device used to transfer the desired stamping force to the corresponding stamp. Set of tools from said tools, to be provided in a stamping machine, a plurality of tools and a plurality of coupling devices being joined together to form a single structural unit.

Description

The invention relates to a punching machine with a feed device for the cyclical further movement of the material to be punched by the punching machine; with a series of tool elements, each having a die arranged in a die holder, a guide arranged at a distance above it for a punch and a punch; with a head plate of the drive device acting on the punch; and with the tool elements associated, switchable and disengageable coupling devices that serve the optional transfer of punching force to the assigned punch.

In a known punching machine of this type (US-A-3 048 328), the matrices of the tool elements are fastened to the machine table, while the punch stamps of the tool elements are fastened to the head plate of the punching machine via intermediate parts. If the punching machine is to be converted to the production of other punched parts, replacement work must be carried out on both the machine table and the top plate and the exchanged dies and punch stamps must be individually adjusted again.

A punching machine is known from the magazine “Bands, sheets, tubes” (1976), pages 448 to 450, in which the tool elements, including punching stamps, are each C-shaped and individually fastened to the machine table. Coupling devices that can be switched on and off are not available. With each downward movement of the head plate under the action of the drive device of the punching machine, all of the punching dies provided are simultaneously moved toward the material to be punched and the dies, so that they all perform a (punching) cut at the same time. The punching machine works according to the principle of the follow-up cut, in which the material to be punched is cycled through the punching machine between the punching strokes, a series of identical punchings or identical punching patterns being punched one after the other and a specific workpiece to be punched having several identical punchings or punching patterns one after the other . This limits working with the punching machine to the production of workpieces, the overall punching pattern of which can be divided into a number of identical individual punching patterns. If, on the other hand, a workpiece, for example, has a certain punch opening only once, this punch opening must be punched subsequently.

From the magazine ceWerkstattstechnik .., 56th year 1966. Issue 10, pp. 497/498, a punching machine with a row of tool elements lying transversely to the feed direction of the material to be punched and coupling devices that can be switched on and off are known. This machine has a common die plate for the dies and above it a common guide plate with bores in which the lower end regions of the punches slide up and down. However, the punches are held in a die holding plate which is attached to the top plate of the punching machine. In addition, no interchangeably inserted guide sleeves are provided in the guide plate.

From DE-A-2 538 605 a single tool element with a C-shaped frame is known, which has a die inserted in the lower arm of the frame and a guide sleeve which is interchangeably inserted in the upper arm of the frame, in which the stamping die accommodated therein is axially displaceable against spring action .

The invention has for its object to provide a punching machine which can be converted more easily to other punched parts.

• - ein über deren Länge sich erstreckendes Unterteil, das die Aufnahme für die Matrizen bildet;
• - ein über deren Länge sich erstreckendes, mit Abstand darüber angeordnetes Oberteil, das eine Führungsplatte bildet, in die Führungshülsen für die Stanzstempel auswechselbar gesteckt sind;
• - die Stanzstempel.

To achieve this object, the punching machine is characterized according to the invention in that several tool elements are combined to form a structural unit resting on the machine table, which has:

• - A lower part extending over its length, which forms the receptacle for the matrices;
• - An upper part which extends over its length and is arranged at a distance above it and forms a guide plate, in which guide sleeves for the punch are exchangeably inserted;
• - the stamps.

The punching machine according to the invention is universal and can also punch workpieces which have a total punching pattern which cannot be subdivided into identical individual punching patterns, particularly quickly and with high precision.

In the punching machine according to the invention, the guide sleeves with punch and the dies can be exchanged extremely easily or removed or inserted according to the respective punching task, and one or more punches can be switched off from a provided punch arrangement with each punch stroke so that he or she does not perform any punching. This enables a quick change to other punching patterns. The punching machine according to the invention can work according to the follow-up cutting principle or the complete cutting principle. In the case of die cuts according to the follow-up cutting principle, the individual cuts of the cut sequence can, if necessary, be carried out with punching dies switched on and off differently, which considerably expands the spectrum of parts which can be produced using the follow-up cutting principle. The punching machine according to the invention also rationalizes punching according to the complete cutting principle, because with a single row of tool elements, each of which has a punch with an associated die, a larger number of different parts can be punched if one switches on and off other punch depending on the part to be punched , and because new tool sets can be put together quickly by simply replacing, removing or adding guide sleeves with punch and die nen. Overall, the production of parts that are similar to one another, so-called part families, is also significantly simplified, as will be explained in more detail below. The cutting off of the respectively punched part from the material to be punched which is fed as a continuous band can also be integrated into the function of the punching machine according to the invention by providing a punching punch which acts as a severing punch and which is only switched on at the end of the sequence of the individual punchings. The punching machine according to the invention can be built much lighter and smaller than conventional punching machines in terms of the installed drive power, since these had to be designed for maximum occupancy, i.e. use of the entire machine length in the direction of material movement for use of the punch and the resulting forces and required power.

Preferred developments of the punching machine according to the invention result from claims 2 to 4. The intermediate pieces of the coupling devices are preferably pneumatically, hydraulically, mechanically or electromagnetically displaceable. The tool element assembly and / or the coupling device assembly can preferably be replaced as a whole.

A switchable coupling device is advantageously provided for each punch that can be switched on and off, although it is also possible to provide for punching dies to be switched on and off in groups. Conveniently, all punches of the punch arrangement provided can be switched on and off.

The invention further relates to a tool set for installation in an existing press; with matrices arranged in die mounts, with guides for punching dies arranged at a distance above it and with punching dies; and with coupling devices which can be switched on and off and which serve for the optional transfer of the punching force to the associated punch, characterized in that a number of the punching dies and dies are combined to form a structural unit in which a lower part extending over their length forms the receptacles for the dies and one over the length of which extends and arranged at a distance above the upper part forms a guide plate into which axially displaceable guide sleeves for the axially displaceable stamping dies are inserted; and that a number of coupling devices is also combined into a single unit.

The punching machine according to the invention is preferably electronically controlled, in particular CNC-controlled (computerized numerical control). This control can take over the switching on and off of the individual punches or the drive of the individual punches and, if necessary, the feed device. The control is advantageously carried out by means of an integrated, program-controlled computer, to which the data for the workpiece to be manufactured are fed. The reaching of the top and bottom dead center of the punching stroke can be detected by sensors, the respective punch stamps being switched on after top dead center and being switched off after bottom dead center. In addition, a check can be carried out, for example, by means of a sensor as to whether punching waste comes from all the punching dies that are switched on, the punching machine automatically switching off in the event of faults not noticeable by punching waste not occurring. The punching machine according to the invention can be fully automated and, as a result, can also be operated without operating personnel, for example at night. The control can be programmed, for example, using a keypad, punched tape or information carrier cassette.

• Fig. 1 eine Ansicht des Stanzstempelbereichs einer Stanzmaschine, wobei die Blickrichtung quer zur Längsrichtung der Stanzmaschine ist;
• Fig. 2 einen Vertikalschnitt in größerem Maßstab durch ein Werkzeugelement der Stanzmaschine gemäß Fig. 1;
• Fig. 3 einen Längsschnitt im vergrößerten Maßstab eines Teils des Werkzeugelements von Fig. 2, sowie Draufsichten auf eine Matrizenaufnahme und einen Matrizen-Schneideinsatz;
• Fig. 4 eine mit der erfindungsgemäßen Stanzmaschine herstellbare Teilefamilie;
• Fig. 5 eine abgewandelte Ausführungsform der Stanzmaschine mit einem Revolverteller.
• Fig. 1 zeigt von einer Stanzmaschine eine Kopfplatte 2 und einen Maschinentisch 38. Die Kopfplatte 2 ist mittels einer nicht gezeichneten Antriebseinrichtung, beispielsweise in Form eines hydraulischen Stanzhubantriebs, längs Führungssäulen 6 auf den Maschinentisch 38 zu bewegbar. Auf dem Maschinentisch 38 ist ein Unterteil 44 und mit Abstand darüber ein Oberteil 46 angebracht, wobei das Unterteil 44 und das Oberteil 46 über die ganze Länge des Maschinentischs 38 durchgehen können, in kürzere Abschnitte unterteilt sein können oder auch pro Werkzeugelement 42 ein eigenes Teil bilden können. Die Kopfplatte 2, die beim dargestellten Ausführungsbeispiel die Form eines sich in Längsrichtung der Stanzmaschine erstreckenden Balkens hat, erstreckt sich oberhalb der Reihe der Werkzeugelemente 42. Zur Ausführung der Stanzbewegung wird die Kopfplatte nach unten bewegt und beaufschlagt einen, mehrere oder alle Werkzeugelemente 42 mit Stanzkraft.

The invention and further development of the invention are explained in more detail below on the basis of exemplary embodiments which are shown schematically. Show it:

• 1 is a view of the stamping area of a punching machine, the viewing direction being transverse to the longitudinal direction of the punching machine;
• FIG. 2 shows a vertical section on a larger scale through a tool element of the punching machine according to FIG. 1;
• FIG. 3 shows a longitudinal section on an enlarged scale of a part of the tool element from FIG. 2, as well as top views of a die holder and a die cutting insert;
• 4 shows a family of parts that can be produced with the punching machine according to the invention;
• Fig. 5 shows a modified embodiment of the punching machine with a turret.
• 1 shows a head plate 2 and a machine table 38 of a punching machine. The head plate 2 can be moved along guide columns 6 onto the machine table 38 by means of a drive device (not shown), for example in the form of a hydraulic punch stroke drive. On the machine table 38 there is a lower part 44 and at a distance above an upper part 46, the lower part 44 and the upper part 46 being able to pass over the entire length of the machine table 38, can be divided into shorter sections or can also form a separate part for each tool element 42 can. The head plate 2, which in the illustrated embodiment has the shape of a bar extending in the longitudinal direction of the punching machine, extends above the row of tool elements 42. To carry out the punching movement, the head plate is moved downwards and applies punching force to one, several or all of the tool elements 42 .

The details of a tool element 42 and its punching force application can be seen more in detail from FIG. The tool element 42 shown consists essentially of a die holder 24 arranged on the lower part 44 with as inserted tem cutting insert 26 trained die, a punching unit 48 inserted into the upper part 46 from above, which can be moved downwards against the action of springs 50 to the die, and a coupling device attached to the head plate 2 at the bottom. The coupling device essentially consists of a vertical blind bore 54 which is open at the bottom and has a plunger 56 which is arranged to be vertically displaceable therein and serves to switch the plunger 56 on and off. Below the cutting insert 26, an opening 40 is provided in the lower part and in the machine table 38 for removing the punching waste.

In the illustrated passive position of the intermediate piece 34, there is free space in the blind bore 54 above the tappet 56, so that when the head plate 2 moves downward, the tappet 56 is initially carried downward because of the friction in the blind bore 54, but then when the head plate is moved further downward 2 does not receive a punching force from above, but remains on the top of the punching stamp unit 48 without transmitting punching force. If the plunger 56 is switched on by moving the intermediate piece 34 to the left and the head plate 2 is lowered to carry out a punching movement, then the plunger 56 presses on the punching stamp unit 48 and presses it down against the action of the springs 50. The lower end face 52 of the punch unit 48 acts as a hold-down device. A punch 18 is vertically movable in the punch unit 48, FIG. 3 showing an embodiment of this. The punch 18 passes through the cutting insert 26 upon further downward movement of the head plate 2 and carries out the actual punching.

If a material strip to be punched is fed in cycles in the longitudinal direction of the punching machine through the space between the upper part 46 and the die holder 24, the individual punching dies 18 can be switched on and off as required by a CNC control. E.g. For each punch stroke, an identical recess can be punched next to the other, while certain holes in the workpiece, for example, are only punched once after a certain number of recesses and a separating cutting punch is actuated only once at the end of the workpiece with the punched row of recesses becomes.

The tool elements 42 or the punch 18 do not have to be arranged in a straight line, but the punch 18 can also be arranged behind and partly in front of the plane of the drawing, as viewed in the direction of FIG. 1. It is also possible to provide a plurality of switchable punching dies 18 in one plane transverse to the longitudinal extent of the punching machine. A group of a plurality of dies 26, stamping die units 48 and coupling devices can also be combined as a structural unit or tool set. It is also possible to attach a group of several coupling devices as a structural unit under the head plate 2, even if the dies 26 and punching units 48 are used individually. The punch unit 48 is inserted in the simplest way from above into a corresponding hole in the upper part. The same applies to the die 26. The tool elements 42 can be provided not only in one row in the longitudinal direction of the punching machine, but also in several rows one behind the other, as seen in the viewing direction of FIG. 1. A punching machine is thus in front of one another with the individual tool elements 42 or groups of tool elements 42 can be arranged at a selectable position on the punching machine, adapted to the particular punching task. The tool elements 42 are also ideal for retrofitting existing punching machines.

In Fig. 3, a preferred embodiment for a punch unit 48 is shown in more detail. An upper tool head 58, a lower guide sleeve 60 and a spring element 62 arranged therebetween can be seen. A stamping punch holder 64, through which the actual punching punch 18 of smaller diameter is arranged, extends through a concentric inner space of these parts 58, 60, 62 that runs from top to bottom is attached. The stamping stamp unit 48 is designed in a manner lubricated from the inside by an oil supply channel 66, the lubricating oil reaching down to the cutting stamp 18 and its passage through the lower end of the guide sleeve 60. When the plunger 56 (FIGS. 1 and 2) is pressed onto the respective tool head 58 when the head plate 2 moves downward, the entire punching stamp unit 48 first moves downward until its lower end face rests on the material to be punched as a hold-down device. The further downward movement of the head plate 2 causes the respective spring element 62 to be compressed and thereby the actual punch 18 to emerge from the bottom of the punch unit 48 through the associated die 26.

The die shown in Fig. 3 is a cutting insert in a so-called one-way version, which is therefore not re-sharpened when blunt but is replaced. The cutting punch receptacle 24 has a receptacle cutout 70, which is circular but has a straightening 68, as seen from above. The cutting insert 26 provided with a corresponding circumferential contour is inserted into this from above and fastened with small screws. The cutting insert 26 contains the actual die cutting opening 28. The straightening 68 ensures that the cutting insert 26 is in a precise position.

Fig. 4 shows a simple example of a so-called family of parts from the switch housing construction. Such families of parts, also of a much more complicated type, can be produced particularly efficiently with a punching machine designed according to the invention.

4 a) shows the simplest part of the family of parts, in which there are seven large punched recesses 72 arranged at an identical distance and a smaller punched recess 74 between them. To produce this part 76, two punches 18 are provided in the longitudinal direction of the punching machine, one for punching a larger recess 72 and the other for punching a smaller recess 74. Both punches are actuated at the same time after the part 76 has been advanced by the feed length a. A separating cutting punch could only be provided for separating the finished part 76 from the strip-shaped punching raw material, which is only switched on once after seven punching strokes.

The part 78 according to FIG. 4b) differs from the part 76 in that it has a shorter length and in that an elongated recess shape 74 'has to be punched in part of the smaller recesses 74. Here, for example, an additional punch can be provided in the longitudinal direction of the punching machine, spaced apart from the two punch punches described above, which punches the extensions of the recesses 74 '. This additional punch is to be controlled so that it does not perform the punching every time the punching machine is punched, but only where this is specified by the program control of the punching machine. Otherwise this additional punch remains switched off. In addition, the separating cutting punch is to be controlled in such a way that after a part 78 with five recesses 72 it is cut off.

The part 80 according to 4c) differs from the parts 76 and 78 in that the larger recesses 72 have a smaller mutual center spacing a, the smaller recesses 74 "are smaller than before, and in some of the sheet metal tabs 72 holes 82 between the recesses are to be punched and that a special recess 84 with a different shape is to be punched at the beginning of part 80. Here, with regard to recesses 72 and 74 ", the procedure is the same as for part 76. For the holes 82 and the separate recess 84, a separate punch is provided in each case, analogously to that described in connection with FIG. 4b) for the extension of the smaller recesses 74 '. The additional punches are to be switched on in a controlled manner when a hole 82 or a recess 84 is to be punched.

1 shows a top view of a turret plate 90 which can be used in the punching machine. The turret plate 90 has an essentially octagonal shape with rounded corners and can be rotated in 90 ° or 45 ° sections about its vertical axis of rotation 92. A total of 14 through bores 94 are distributed over the circumference of the turret plate 90 in such a way that at least some of the cut-off positions of the turret plate 90 have a plurality of bores 94 arranged along a straight line 96 in the longitudinal direction of the punching machine. At a distance below the turret plate 90 is another, in Fiq. 5 invisible, similar revolver plate. These two turret heads can be incremented together. The lower turret plate rests on the machine table 38, but can rotate on it in a rotationally sliding manner when switching over.

The bores 94 serve to insert punching die units 48 in the same manner as shown in FIG. 2. On the lower, not visible turret plate, die receptacles 24 and dies 26 are arranged in the same places in the same way as shown in FIG. 2.

By rotating the turret plate 90 together with the turret plate underneath it, which is not visible, other tool elements 42 can thus be brought into a position in which they can be acted upon by the head plate 2 with punching force, whereby in turn individual punching dies can be switched off.

Claims (6)

1. A stamping machine including an advance means for intermittently advancing the material to be stamped through the stamping machine; comprising a series of tool members (42) each including a die (26) disposed in a die receptacle (24), a guide spaced thereabove for a stamping punch

(18), and a stamping punch (18); and comprising a head plate (2) of the drive means, which acts upon the stamping punches (18); and comprising coupling means (34, 36) which are associated with said tool members (42) and adapted to be activated and deactivated and serve for selectively transferring stamping force to the associated stamping punch (18), characterized in that several tool members (42) are combined to form a constructional unit resting on the machine table (38) and comprising:

- a bottom part (44) extending across the length thereof and forming the receptacles for said dies (26);

- a top part extending across the length thereof and being spaced thereabove and forming a guide plate (46) into which guide sleeves (60) for the stamping punches (18) are inserted in re- placable manner;

- said stamping punches (18).

2. A stamping machine according to claim 1, characterized in that the particular coupling means includes an intermediate member (34) disposed on said head plate (2) and movable in reciprocating manner between an active position, in which the stamping force is transferred by said head plate (2) to the associated stamping punch (18) via said intermediate member (34), and a retracted passive position in which said head plate (2) is movable relative to said stamping punch (18) without stamping force being transferred thereto.

3. A stamping machine according to claim 1 or 2, characterized in that several coupling means (34, 36) are combined to form a constructional unit.

4. A stamping machine according to any one of claims 1 to 3, characterized in that said tool members (42) are carried by a turret plate (90).

5. A tool set for installation in an existing press; comprising dies (26) disposed in die receptacles (24), guides spaced thereabove for stamping punches (18), and stamping punches (18); and comprising coupling means (34, 36) which are adapted to be activated and deactivated and serve for selectively transferring stamping force to the associated stamping punch (18), characterized in that a series of said stamping punches (18) and dies (26) is combined to form a constructional unit in which a bottom part (44) extending across the length thereof forms the receptacles for said dies (26), and a top part extending across the length thereof and spaced thereabove forms a guide plate (46) having inserted therein in replaceable manner guide sleeves (60) which are axially displaceable against spring action and serve for said stamping punches (18) which are axially displaceable therein against spring action; and in that a series of coupling means (34, 36) also is combined to form a constructional unit.

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