EP2177289B1 - Machine tools and method for discharging a workpiece part - Google Patents

Abstract

The tool has a discharging slope (25) arranged such that a workpiece part is severed from a workpiece supported on a support surface (23) of a punching die (11'), which is displaced in a rotational, tilting or linear movement from a processing position partially overlying the discharging slope towards a removal position on the discharging slope. The workpiece part is severed from a workpiece supported on the support surface of the punching die, which slides towards a discharging position located beneath the support surface and adjacent to the punching die. An independent claim is also included for a method for discharging workpiece parts severed from a plate workpiece via a punching operation.

Description

The present invention relates to a machine tool for cutting and / or forming plate-like workpieces, preferably of sheets according to the preamble of claim 1 (see, for example JP-U-04043416 ) and a method for discharging a particular shaped workpiece part of a punching die on a machine tool for cutting and / or forming plate-like workpieces, preferably of sheets according to the preamble of claim 9.

Workpiece parts which rest on a bearing surface of a punching die at a punching / forming station of a machine tool after the separating machining can be discharged by being pushed through the scrap grid, wherein a scraper provided on the punching tool or punch serves as a guide. However, this procedure is particularly problematic in the case of formed workpiece parts, since the wiper represents a collision contour for the forming. For workpiece parts with transformations (eg thread passages, gills, settlings, beads, etc.), which are on the bearing surface of the punching die after the separating processing, therefore, the problem arises that they can not be safely discharged and therefore possibly by so-called Micro-joints remain connected to the (residual) workpiece, which require a manual reworking (breaking / deburring). But even with workpiece parts without forming, the push is associated with loss of time and low process reliability.

From the US 2006/0027626 A1 has become known a machine tool, in which a punching die is used, on which both a deformation and a separating machining of a workpiece part can be made. There, a workpiece part, which is connected via a micro-joint with the remainder workpiece, first bent at a bending edge of an opening in the punching die down. Subsequently, the micro-joint is positioned at the bending edge and the formed workpiece part is separated from the remaining workpiece by punching machining. The workpiece part separated from the remainder workpiece is subsequently discharged through the opening in the punching die. The method described there limits the size of the auszuschleusenden workpiece parts to the size of the opening. Also, in the method described there, the workpiece parts separated from the remainder workpiece do not fall with a controlled movement and can therefore hit the edges of the opening and thereby be damaged.

Object of the invention

It is the object of the present invention to develop a machine tool and a method for discharging a workpiece part to the effect that that the rejection can be controlled and carried out with little loss of time.

Subject of the invention

This object is achieved by a machine tool with the features of claim 1.

According to the invention, it is proposed that the workpiece part be firstly moved out of the machining position by a turning, tilting and / or linear movement into a discharge position on a discharge chamfer of the tool die in order to subsequently transfer the workpiece part with a sliding movement to a discharge position located next to the punching die. This allows the rejection of the workpiece part controlled by the punching die and done without the use of a scraper as a guide. The method described above is particularly suitable for the removal of deformed workpiece parts, as in particular workpiece parts having a deformation down, can be stored in the processing position, since a clearance is formed by the Ausschleusschräge on the punching die, in which the deformation can intervene , It is understood that the Ausschleusschräge does not necessarily have to be a flat surface, but that may possibly also have a curvature. Also, the machine tool can be designed such that the punching die and the punch can be exchanged for other tool dies and tool dies, in particular against such punches and dies, which allow a deformation of the workpiece or the partially cut workpiece part.

In the machining position, the workpiece part can in this case partially project beyond the bearing surface and after the free cutting, which is made at an opening in the bearing surface, execute a tilting movement about the edge. In this case, it is necessary that the workpiece part is positioned so that the center of gravity is arranged in the processing position not on the support surface, but over the Ausschleusschräge.

The Abstanzfläche here typically runs at a right angle to the (horizontal) bearing surface. The workpiece part to be cut free from the remainder workpiece protrudes in the machining position over the support surface in the horizontal direction, i. the workpiece part is not in the processing position on the support surface. The workpiece part is separated from the remainder of the workpiece by the punch is lowered along the Abstanzfläche with a lifting movement, whereby the workpiece part is cut free from the rest of the workpiece resting on the support surface and lowered with a combined linear and rotary movement on the Ausschleusschräge.

The workpiece can be punched at the opening in the support surface, eg to separate the workpiece from the remainder of the workpiece. The workpiece part which has been cut free at the opening can hereby be brought onto the support surface by this executing a tilting movement about an edge on the outer edge of the support surface, to which the discharge slant immediately adjoins. If the punching die has a scraper surface in addition to the opening, it is possible to machine the workpiece at the opening by means of a punch with an off-center cutting edge with respect to the tool rotation axis, which can be positioned by rotation over the opening or over the scraper surface at the Abstanzfläche the workpiece part to be separated from the remainder of the workpiece. The dimension of the opening can in this case coincide for the separating machining of the workpiece substantially with the dimensions of the cutting edge formed on the punch. It is also possible to use the opening for ejecting workpiece parts which pass through the opening of the punching die into one under the punching die intended Ausschleusposition be spent.

Here, the workpiece part to be separated is positioned in the processing position on the opening and separated by separating processing of the remaining workpiece resting on the support surface. It is understood that for discharging large workpiece parts, the support surface can form only a narrow, circumferential edge of the punching die, which limits a large-area, in particular circular opening in the punching die.

In a particularly preferred embodiment, a chute is arranged at the Ausschleusposition, which adjoins the Ausschleusschräge the punching die. The slide is in this case mounted so that its upper edge is positioned adjacent to the lower edge of the Ausschleusschräge, so that the sliding movement of the workpiece part can be continued on the slide to eject the workpiece part of the machine tool. The slope of the chute here can correspond at least in the adjoining the Ausschleusschräge portion of that of the Ausschleusschräge, so that a continuous movement is ensured. It is understood that at the discharge position also other transport means, e.g. Conveyor belts can be arranged, which allow a discharge of the workpiece part.

In an advantageous embodiment, the Ausschleusschräge is formed on a lateral surface of a pyramid or truncated conical punching die. A punching die having such a geometry has at the tip of the conical or truncated pyramid the bearing surface for the workpiece part, in which an opening for engagement for a punch is formed. The lateral surface of the truncated cone or the lateral surfaces of the truncated pyramid in this case form one or more inclined planes on which or on which the workpiece part can slide along. It is understood that in addition to pyramid or frustum-shaped punching dies and punching dies can be used with other, especially asymmetric geometries.

Preferably, the lower edge of the discharge slope of the punching die adjoins the die receiving, in which the punching die is mounted. This is favorable, since in this way the stroke movement required for positioning the matrix holder can be minimized. It goes without saying that the edge of the die receptacle can likewise have a bevel, so that a continuous transition of the workpiece part from the punching die into the Ausschleusposition is ensured.

In a particularly advantageous embodiment, the bearing surface with the Ausschleusschräge an angle between 20 ° and 80 °, preferably between 25 ° and 45 °. These angles have proven to be particularly favorable to allow a controlled transition from the machining position to the discharge position. It is understood that the term edge also a rounded edge can be understood, at which a tilting of the workpiece part can take place.

Preferably, the machine tool comprises a control unit for positioning the workpiece part in the machining position such that the center of gravity of the workpiece part is above the Ausschleusschräge. This ensures that the workpiece part performs a tilting or rotational movement about a provided on the edge of the support surface edge after the separating processing under gravity and thereby spent from the processing position to the discharge position. If, in this case, the workpiece part is separated from the remainder workpiece by an opening formed on the support surface, the control unit may, for a given contour of the workpiece part, determine the sequence of the sections of the contour to be cut during punching so that the last section of the contour to be cut at the opening has a distance from the center of gravity of the workpiece part, which is greater than the distance to the tilting edge.

In an advantageous embodiment, the machine tool additionally comprises a die receptacle in which the punching die is mounted, a punch receptacle in which a punch is mounted, and a drive unit, by means of which the punch receptacle and the die receptacle along a lifting axis are movable towards each other to edit the workpiece part in the machining position separating. When separating editing of the punch in a introduced at the bearing surface of the punching die formed opening or guided along the Abstanzfläche to separate the workpiece part from the remainder of the workpiece. It is understood that in addition to the drive unit, by means of which a linear movement takes place along the stroke axis, a further drive unit may be provided by means of which the die holder and / or the punch holder can be rotated about the lifting axis to the punching die if Required to rotate so that the lower end of the Ausschleusschräge is located adjacent to the Ausschleusposition.

The invention also relates to a method for discharging a particular shaped workpiece part having the features of claim 9.

According to the invention, the workpiece is optionally punched at an opening in the support surface of the punching die or at a provided between an edge formed on the outer edge of the support surface and the Ausschleusschräge the punching die provided Abstanzfläche. To make this possible, the punch and / or the punching die can be rotated about an axis of rotation to position the punch either over the opening or over the Abstanzfläche or the cutting edge. It is understood that a plurality of openings may be provided for engagement by the punch in the punching die. In this case, for machining the workpiece, the punching die can be rotated relative to the punch in more than two different positions and fixed there, as in the DE 10 2006 049 044 the applicant, which is incorporated herein by reference for the purposes of this application.

In an advantageous variant, the punching die is mounted in a die receptacle, which is moved along a lifting axis before or after the separating machining, until the discharge slope of the punching die joins a chute of the machine tool provided at the removal position. In this case, the die holder can be arranged already in the processing position so that the Ausschleusschräge joins the chute, but it is alternatively also possible that Matrizen recording only after the separating processing, ie while the workpiece part slides along the Ausschleusschräge along so far to move down, that the lower edge of the Ausschleusschräge is positioned adjacent to the chute. This is particularly favorable for workpiece parts with large transformations to produce more space for discharging below the workpiece support or if a machining of the workpiece part above or below the workpiece level should be done.

Particularly preferably, the workpiece part is positioned in the processing position such that the center of gravity of the workpiece part is above the discharge slope. As stated above, the last section of the contour of the workpiece part to be separated can be selected so that the distance of this section to the center of gravity of the workpiece part is greater than the distance to the tilting edge, so that the workpiece part under the action of gravity performs a tilting movement.

Further advantages of the invention will become apparent from the description and the drawings. The embodiments shown and described are not to be understood as exhaustive enumeration, but rather have exemplary character for the description of the invention.

Fig. 1

eine schematische Darstellung einer Ausführungsform einer erfindungsgemäßen Werkzeugmaschine,

Fign. 2a-c

schematische Darstellungen eines umgeformten Werkstückteils auf einer Auflagefläche einer Stanzmatrize ohne (Fig. 2a) und mit Ausschleusschräge (Fign. 2b,c),

Fign. 3a-c

schematische Darstellungen von drei Schritten zum Ausschleusen des in Fig. 2c gezeigten Werkstückteils von der Stanzmatrize,

Fign. 4a,b

schematische Darstellungen eines Stanzstempels mit außermittiger Schneidkante sowie einer Stanzmatrize mit außermittig angeordneter Abkantfläche,

Fign. 5a,b

schematische Darstellungen einer Stanzmatrize mit mittiger Abstanzenfläche bzw. mit einer Öffnung in einer Auflagefläche, unter der die Ausschleusschräge angeordnet ist, und

Fign. 6a-c

schematische Darstellungen von drei Schritten beim Ausschleusen eines Werkstückteils von der in Fig. 5a gezeigten Stanzmatrize.

Show it:

Fig. 1

a schematic representation of an embodiment of a machine tool according to the invention,

FIGS. 2a-c

schematic representations of a formed workpiece part on a contact surface of a punching die without ( Fig. 2a ) and with Ausschleusschräge ( FIGS. 2b, c )

FIGS. 3a-c

Schematic representations of three steps to remove the in Fig. 2c shown workpiece part of the punching die,

FIGS. 4a, b

schematic representations of a punch with off-center cutting edge and a punching die with eccentrically arranged Abkantfläche,

FIGS. 5a, b

schematic representations of a punching die with central Abstanzenfläche or with an opening in a support surface, under which the Ausschleusschräge is arranged, and

FIGS. 6a-c

schematic representations of three steps in the discharge of a workpiece part of the in Fig. 5a shown punching die.

Fig. 1 shows a machine tool 1 for cutting and / or forming plate-like workpieces in the form of a stamping / forming machine for processing sheets. The punching / forming machine 1 has a C-shaped machine frame 2 , in the throat area of which a workpiece support 3 designed as a workpiece support is arranged, which serves for supporting a workpiece to be machined in the form of a sheet 4 . On its upper side, the workpiece table 3 forms a horizontal support plane 5 for the sheet 4 to be processed , which is parallel to the x / y plane of the in Fig. 1 shown coordinate system runs. By means of a coordinate guide 6 , the clamping device 7 clamped sheet 4 in the support plane 5 of the workpiece table 3 is displaced.

At the front end of the upper leg of the C-shaped machine frame 2, a punch-receiving 8 is arranged, in which a punch 9 is mounted. Furthermore, at the front end of the lower leg of the C-shaped machine frame 2, a female receptacle 10 is provided, in which a Punching die 11 is stored. The punch 9 and the punching die 11 form a tool 12 for cutting the sheet 4.

A drive unit of the punching / forming machine 1 is formed by a punch drive 13 and a die drive 14 in the form of linear drives. By means of the punch drive 13, the punch receptacle 8 together with the stamped or fixed punch 9 mounted along a lifting axis 15 relative to the workpiece table 3 can be raised and lowered. In a comparable manner, the die holder 10 together with the stamped die 11 mounted or fixed therein can be raised and lowered by means of the die drive 14 along the lifting axis 15 relative to the workpiece table 3. Furthermore, the punch holder 8 and the die holder 10 are independently rotatable by means of a rotary drive, not shown in detail, about an identical with the lifting axis 15 tool axis of rotation 16 .

At the coordinate guide 6, a linear magazine 17 is provided with further tools 12. The tools 12 located in the linear magazine 17 are each held by a tool cassette 18 and can be fixed to the stamp holder 8 or the female holder 10 as required for machining the sheet 4, with tools 12 in particular also being used for forming the workpiece 2 can be kept in the linear magazine 17.

During tool change and workpiece machining, all drives of the punching / forming machine 1 are controlled by means of a numerical control unit 19. In particular, the numerical control unit 19 comprises storage means 20 for storing tool data, and control means 21 for detecting both the raising, lowering and rotating movements of the punch holder 8 and the lifting, lowering and rotating movements of the die holder 10 based on the Figs stored data on the workpiece 4 and the tool 12 to measure and control.

Fig. 2a shows a detailed view of the stored in the female receptacle 10 punching die 11 of Fig. 1 , on whose flat bearing surface 23 a deformed workpiece part 22 rests that of the in Fig. 1 shown workpiece 4 by punching processing along a formed in the support surface 23 opening 24 separated has been. At the in Fig. 2a shown punching die 11 has the problem that the separated, resting on the support surface 23 workpiece part 22 must be ejected by pushing, which can be done for example by means of a (not shown) scraper (eg in the form of a Eladurfeder) as a guide on the punch 9. In this case, however, the forming formed on the workpiece part 22 acts as a disturbing contour.

However, the pushing can be dispensed with if the punching die 11 as in FIGS. 2 B , c shown has a truncated pyramidal geometry, wherein the top surface of the truncated pyramid forms the support surface 23 for the workpiece part 22 and the lateral surface of the truncated pyramid serves as Ausschleusschräge 25 . As in Fig. 2b respectively. Fig. 2c is shown, the upwardly or downwardly formed workpiece part 22 after the separating processing only partially on the support surface 23 and can be discharged along the Ausschleusschräge 25, which will be described below with reference to the FIGS. 3a -c is described. Here it is favorable, if - as in FIGS. 2b, c shown - the Ausschleusschräge 25 adjacent at its lower edge to the female receptacle 10. The diameter of the punching die 11 or the die holder 10 can be in the range of approximately 100 mm, for example.

Fig. 3a shows the workpiece part 22 in a machining position B, in which this as in Fig. 2c shown rests on the support surface 23 of the punching die 11 and is separated from the remainder of the workpiece 4 by the punch 9 engages in the opening 24. As in Fig. 3a can also be seen, is the workpiece part 22 after the separating machining with its center of gravity S on the Ausschleusschräge 25. To effect this, the cutting of the contour of the workpiece part 22 is planned in the control unit 19 so that the center of gravity S at the final separating cut so far away from the opening 24 that it no longer lies on the support surface 23. If this is the case, the free-cut workpiece part 22 tilts under the action of gravity about a tilting edge 26 formed on the edge of the support surface 23 from the processing position B to a discharge position AB, in which the workpiece part 22 rests on the discharge slope 25 of the punching die 11, cf. Fig. 3b , The Ausschleusschräge 25 is inclined relative to the support surface 23 of the punching die 11 and the workpiece plane 5 at a tilt angle a, which is approximately 45 ° in the present case.

The workpiece part 22 subsequently slides under the action of gravity on the discharge slope 25 of the punching die 11 into a discharge position AS (see FIG. Fig. 3c ), in which the workpiece part 22 rests on a subsequent to the Ausschleusschräge 25 rigid chute 27 on which the workpiece part 22 further slides to be discharged from the machine tool 1. In the discharge process described above, the support surface 23 of the punching die 11 is in the workpiece plane 5, to support the workpiece part 22 during the punching process. For this purpose, it is necessary that the die holder 10 is positioned by the punching processing below the workpiece plane 5, for which purpose the die holder 10 is typically lowered by approximately 30 mm with respect to the workpiece plane 5.

It is understood that it is with the in FIGS. 2b, c shown punching die 11 is also possible to edit at a correspondingly provided Ausschleusposition AP, for example by roll forming formed workpiece parts 4 above or below the workpiece plane 5. In this case, the movement of the punching die 11 along the lifting axis 15 in the in FIGS. 3a-c shown position to make only after the punching editing, while the workpiece part slides on the Ausschleusschräge 25 along. It is further understood that instead of a rigid chute 27, a slide movable along the lifting axis 15 can be provided or another transport means, eg a conveyor belt, can be provided for discharging the workpiece part 22 at the discharge position AS.

In the manner described above, the workpiece part 22 can be quickly removed from the workpiece plane 5, wherein, if necessary, a shift of the workpiece 4 along the workpiece plane 5 for subsequent processing can already be done while the workpiece part 22 slides along the discharge slope 25. It is understood that in addition to the lateral surface 25 of the punching die 11 also further lateral surfaces can serve as Ausschleusschräge, for example, an opposite lateral surface 25 a , to which a in FIGS. 3a-c dashed lines, another slide 27a can connect. Also, the punching die 11 is not mandatory pyramidal and can also be carried out in other ways, for example, truncated cone or asymmetric.

FIGS. 4a , b show such an asymmetric punching die 11 ', in which both the opening 24 for engagement for the punch 9 and between the edge 26 and the Ausschleusschräge 11' formed in the vertical direction (Z-direction) extending Abstanzfläche 28 are arranged eccentrically. The likewise asymmetrically formed punch 9 can by a 180 ° rotation about the axis of rotation 16 with a cutting edge 9a either over the opening 24 (see. Fig. 4a ) or on the Abstanzfläche 28 or at the edge 26 are positioned (see. Fig. 4b ). The workpiece 4 is hereby optionally punched processed by the punch 9 and the cutting edge 9a is brought into engagement with the opening 24 or guided along the Abstanzfläche 28 along. It is understood that the opening 24 can also be widened toward the center of the punching die 11 'in order to allow ejection of workpiece parts through the opening 24. Furthermore, the punch 9 and the punching die 11 'may also be formed as a forming tool, by means of which in addition to the punching at the in the in Fig. 4a shown position a deformation can be made on the workpiece.

As in Fig. 5a As shown, the edge 26 for punching the workpiece may alternatively be arranged centrally on the punching die 11 '. In this case, the central cutting edge 9a of the punch 9 is lowered onto the punching die 11 'in order to punch the workpiece part at the cutting edge 26 or along the cutting surface 28. In this case, no opening is made in the support surface 23 of the punching die 11 ', since the rotation of the punch 9 or of the punching die 11' in this case does not open any additional processing options on the workpiece.

Fig. 5b shows a further punching die 11 ", in which the Ausschleusschräge 25 is mounted below the opening 24 in the support surface 23. The punch 9 in this case has a cutting edge 9a, which can be brought into engagement with the opening 24 to one above the opening 24th In this case, the separated workpiece part is lowered in a combined linear and rotary movement onto the bearing surface 25. It is understood that in the right subregion of the bearing surface 23 there is an additional opening for the workpiece punching editing a workpiece can be introduced. It is further understood that for discharging large workpiece parts other than in Fig. 5b shown the Ausschleusschräge can extend over almost the entire cross-section of the punching die 11 ", in which case the support surface is formed by a narrow, for example, annular edge.

The discharge process at the in Fig. 5a shown punching die 11 'is analogous to in FIGS. 3a-c described Ausschleusprozess, so based on the FIGS. 6a c only the differences to the process already described above will be described. As in Fig. 6a is to be seen, is contrary to Fig. 3a the workpiece piece 22 to be cut free in the processing position B does not rest on the support surface 23, so that it can be lowered from the processing position B into the cutting position 28 by lowering the punch 9 along the cutting surface 28 adjoining the edge 26 Fig. 3b shown Abfuhrposition AB can be spent on the Ausschleusschräge 25. Subsequently, the workpiece part 22 slides along the discharge slope 25 until it reaches the discharge position AS on the chute 27 adjacent to the punching die 11 '. The angle α between the support surface 23 and the Ausschleusschräge 25 can be steeper or shallower than in this case FIGS. 6a-c shown (about 45 °) and is typically between 20 ° and 80 °.

In all cases described above, the discharge is made possible with high process reliability, since the discharge position AS is located below the workpiece support and hooking of the workpiece part can be effectively prevented at the remainder workpiece in the discharge process described above.

Claims (12)

1. A machine tool (1) for cutting and/or forming plate-like workpieces (4), preferably metal sheets, comprising:

   a punching die (11, 11', 11") for severing a workpiece part (22), especially a formed workpiece part (22), disposed in a processing position (B) from a workpiece (4) lying on a support surface (23) of the punching die (11, 11', 11"),

   the punching die (11', 11") having a discharging slope (25) on which a removal position (AB) is formed, into which removal position (AB) the workpiece part (22) can be brought from the processing position (B), preferably under gravity, by a rotational,

   tilting and/or linear movement, and the machine tool (1) having a discharging position (AS) provided beneath a workpiece support (3) and adjacent to the punching die (11', 11"), into which discharging position (AS) the workpiece part (22) can be brought, preferably under gravity, by a sliding movement along the discharging slope (25),

   characterised in
   that the discharging slope (25) of the punching die (11") is arranged under an orifice (24) in the support surface (23) for engagement by a punch (9) or
   that an edge (26) is formed at an outer periphery of the support surface (23) of the punching die (11'), which edge (26) is adjoined by the discharging slope (25), there being formed between the edge (26) and the discharging slope (25) of the punching die (11') a die-cutting face (28).
2. A machine tool according to claim 1, wherein the die-cutting face (28) is arranged off-centre and wherein the support surface (23) has an orifice (24) arranged off-centre for engagement by a punch (9).
3. A machine tool according to either of the preceding claims, wherein a slide (27) is arranged at the discharging position (AS), which slide (27) adjoins the discharging slope (25) of the punching die (11).
4. A machine tool according to any one of the preceding claims, wherein the discharging slope is formed on a lateral surface (25) of a frustopyramidal or frustoconical punching die (11).
5. A machine tool according to any one of the preceding claims, wherein the lower edge of the discharging slope (25) abuts on a die holder (10) in which the punching die (11) is supported.
6. A machine tool according to any one of the preceding claims, wherein the support surface (23) forms with the discharging slope (25) an angle (α) of from 20° to 80°, preferably from 25° to 45°.
7. A machine tool according to any one of the preceding claims, further comprising a control unit (19) for positioning the workpiece part (22) in the processing position (B) in such a way that the centre of gravity (S) of the workpiece part (22) lies over the discharging slope (25).
8. A machine tool according to any one of the preceding claims, further comprising
   a die holder (10) in which the punching die (11) is supported,
   a punch holder (8) in which a punch (9) is supported, and
   a drive unit (13, 14) by means of which the punch holder (8) and the die holder (10) are movable towards each other along a stroke axis (15) in order to process the workpiece part (22) in the processing position (B) by severing.
9. A method for discharging a workpiece part (22), especially a formed workpiece part (22), from a punching die (11, 11') on a machine tool (1) for cutting and/or forming plate-like workpieces (4), preferably metal sheets, comprising:

   severing the workpiece part (22) disposed at a processing position (B) from the workpiece (4) lying on a support surface (23) of the punching die (11, 11'),

   the workpiece part (22) being brought from the processing position (B), preferably under gravity, by a rotational, tilting and/or linear movement to a removal position (AB) on a discharging slope (25) formed on the punching die (11), and

   the workpiece part (22) being brought along the discharging slope (25) by a sliding movement, preferably under gravity, to a discharging position (AS) provided beneath the workpiece support (3) and adjacent to the punching die (11),

   characterised in
   that the processing by severing is performed by engagement of a punch (9) in an orifice (24) formed at the support surface (23), under which orifice (24) the discharging slope (25) of the punching die (11") is arranged, or
   that the processing by severing is performed by guiding a punch (9) along a die-cutting face (28) formed between the discharging slope (25) and an edge (26) at an outer periphery of the support surface (23) of the punching die (11').
10. A method according to claim 9, wherein the punching die (11) is supported in a die holder (10) which is moved, before or after processing by severing, along a stroke axis (15) until the discharging slope (4) of the punching die (11) adjoins a slide (27) of the machine tool (1), which slide (27) is provided at the discharging position (AS).
11. A method according to claim 9 or 10, wherein the workpiece part (22) is positioned in the processing position (B) in such a way that the centre of gravity (S) of the workpiece part (22) lies over the discharging slope (25).
12. A method according to any one of claims 9 to 11, wherein the workpiece (4) is selectively processed by punching either at an orifice (24) in the support surface (23) of the punching die (11') or at the die-cutting face (28).

Images