CN111107967A

CN111107967A - Method for machining a workpiece, computer program product and workpiece machining device

Info

Publication number: CN111107967A
Application number: CN201880060477.5A
Authority: CN
Inventors: 格哈德·哈特曼
Original assignee: Homag Plattenaufteiltechnik GmbH
Current assignee: Homag Plattenaufteiltechnik GmbH
Priority date: 2017-09-21
Filing date: 2018-09-17
Publication date: 2020-05-05
Anticipated expiration: 2038-09-17
Also published as: DE102017121956A1; CN111107967B; WO2019057658A1; EP3684572A1

Abstract

The invention relates to a method for machining workpieces, wherein in a first method step the workpiece is divided into a first partial workpiece and at least one second partial workpiece, and in a second method step the second partial workpiece is machined, characterized in that in the second method step the first partial workpiece produced in the first method step is positioned for machining the second partial workpiece, such that it serves in the second method step as a stop for positioning the second partial workpiece.

Description

Method for machining a workpiece, computer program product and workpiece machining device

Technical Field

The present invention relates to a method for machining a workpiece according to the preamble of the main claim as well as a computer program product and a workpiece machining apparatus according to the preambles of the dependent claims.

Background

It is known, for example, from DE 102015206824 a1 that large-size plate-like workpieces are divided by primary/secondary cutting and fine cutting. The primary cutting is also called longitudinal cutting and the secondary cutting is also called transverse cutting. The plate-like workpiece is divided into a plurality of strip-shaped workpieces by longitudinal cutting. The strip-shaped workpiece is then further divided into a first partial workpiece and a second partial workpiece by at least one transverse cut transverse to the longitudinal direction of the workpiece. In order to produce a final workpiece which does not have a dimension corresponding to the width of the strip-shaped workpiece, the second partial workpiece is rotated, for example, by 90 degrees and is divided into a third partial workpiece and a fourth partial workpiece by the described fine cutting.

In the device known from DE 102015206824 a1, the workpiece is positioned relative to the saw wire by means of a positioning device in the form of a program slide (programschiber) which has clamping jaws which clamp the workpiece. All longitudinal cuts are first completed here, the divided workpiece is then gripped again by the program slide and divided by all necessary transverse cuts, the workpiece obtained in this way is rotated by 90 ° if necessary, and then gripped again by the program slide and divided by fine cuts.

Disclosure of Invention

The purpose of the invention is: a method, a computer program product and a workpiece processing device are provided which enable as complete a processing of a workpiece as possible in a very simple manner without a great loss of time.

This object is achieved by a method having the features of the main claim and by a workpiece processing installation having the features of the side-by-side claims. Advantageous developments are specified in the dependent claims. In addition to that, other important features of the invention can be seen in the following description and the attached drawings. The features mentioned here, both individually and in various combinations, are essential for the invention, and in individual cases need not be explicitly mentioned again.

The invention relates firstly to a method for operating a workpiece processing system. In a first method step, a workpiece which is held by a positioning device, for example a gantry-type program slide with clamping jaws, and which is placed, for example, on an inlet table, in particular a roller table and/or an air cushion table (luffstensentisch), is divided into a first partial workpiece and at least one second partial workpiece. The separation is carried out, for example, by means of a saw which can be moved on the saw frame transversely to the direction of movement of the positioning device.

In a second method step, a second partial workpiece is processed. This includes, when a plurality of second partial workpieces has been produced, the machining of only one of these second partial workpieces, and (preferably in succession) some, but not all, of the second partial workpieces or all of the second partial workpieces, even if only the singular form "the second partial workpiece or a second partial workpiece" is subsequently used for reasons of grammatical simplicity.

For this machining, the second part must be positioned as precisely as possible relative to the machining device. This can be achieved according to the invention in that the first partial workpiece produced in the first method step is held by the positioning device in the second method step. According to the invention, in the second method step, the first partial workpiece is positioned by the positioning device for machining the second partial workpiece, so that the first partial workpiece serves as a stop for positioning the second partial workpiece in the second method step. The term "stop" is not to be understood in a limiting manner only to mean that the second workpiece is thus positioned in only one direction. By means of the division during the first method step, a straight edge is generally produced on the first partial workpiece and the second partial workpiece, parallel to the cutting line, which edge can also be used for a corresponding angular positioning of the second partial workpiece on the first partial workpiece.

The invention also relates to a workpiece processing device, in particular a plate dividing device for dividing plate-shaped workpieces. Such a workpiece processing device comprises a control device and a regulating device with a processor and a memory and is designed for carrying out the above-described method.

According to the invention, the second method step is carried out at a point in time when there are also workpieces, i.e. first partial workpieces, held by the positioning device, rather than, as has been the case hitherto, when the positioning device is again free and a second partial workpiece for processing in the second method step can be gripped or held again by the positioning device. In other words, in the present invention, a precise positioning of the second partial workpiece can be achieved in that the positioning device and the first partial workpiece still held by the positioning device form a stop, which is precisely positioned for the special machining of the second partial workpiece and against which the second partial workpiece can be placed, for example, by an operator or by a mechanical handling device, for example a robot.

It goes without saying here that if a plurality of second partial workpieces are produced in the first method step, it is not only possible to: directly after the production of the second partial piece, the second partial piece is machined in a second method step and the first partial piece is positioned accordingly for this purpose, however, it is also possible: all second partial workpieces are first produced and then, in a second method step, these second partial workpieces or some of them are processed in succession and are correspondingly positioned for this purpose each time with respect to the remaining first partial workpiece.

The invention considerably simplifies and speeds up the machining in the second method step, since the costly insertion of the second part into the positioning device is eliminated. Instead of the second method step being carried out almost compulsorily, as hitherto, when all first method steps on the workpiece have been completed, in the present invention the second method step on the partial workpiece of the workpiece can be carried out almost "on time" and directly after the first method step on the workpiece and before the further first method step on the workpiece is carried out. In this way, the need for temporary storage of the partially machined workpieces is reduced or even completely eliminated if necessary. It goes without saying that, after the second method step on a partial workpiece, the first method step can be carried out again on this workpiece and then the second method step can be carried out again on a further partial workpiece, and so on.

In a first refinement of the method according to the invention, it is proposed that: the processing of the second partial workpiece in the second method step comprises: dividing into a third and a fourth part and/or introducing at least one recess and/or at least one hole. The advantages are particularly pronounced, in particular when the second partial workpiece is further subdivided into a third partial workpiece and a fourth partial workpiece (and, if necessary, further partial workpieces). However, the other types of machining mentioned also achieve significant advantages with the aid of the invention. In a correspondingly equipped workpiece processing device, the complete processing can also be carried out in the second method step, so that both the division and the introduction of the grooves and holes take place. For each machining operation, the first part-piece, which is also held by the positioning device, is positioned accordingly for this purpose and serves as a stop or abutment.

Furthermore, it is proposed that: the positioning of the second part-piece during the second method step is related to the position of one of the recesses or the positions of a plurality of recesses and/or at least one hole. This means that, in the type of positioning on the first part, it is taken into account which second method steps are to be followed after the predetermined process sequence.

It is furthermore possible that: the second part can be rotated by preferably 90 ° between the first method step and the second method step. In particular, if the machining in the second method step comprises a division, for example by means of a saw, a so-called "fine cut", that is to say a workpiece having a width which is smaller than the width of the first partial workpiece and the second partial workpiece, can be produced in this way. However, in the machining by including the introduction of at least one recess and/or at least one bore, the machining flexibility is also significantly increased thereby. The rotation is in this case 90 ° in the simplest case. In particular, other angles can in principle also be considered, if corresponding additional positioning means are present which enable an angularly precise positioning. Such additional positioning means may in the simplest case comprise optical markers.

As already mentioned, it is also possible to realize according to the invention: in a second method step, the second partial workpiece is machined, in particular divided, a plurality of times and for this purpose the first partial workpiece is repositioned a plurality of times.

It is furthermore advantageous: the division is performed by using a saw, a milling cutter, a laser cutting device or a water jet cutting device. These devices are simple to implement and allow very precise division of the workpiece.

The present invention may further comprise: the initial workpiece is divided into a plurality of workpieces before the first method step, and then at least one of the workpieces is further divided in the first method step and processed, in particular divided, in the second method step, preferably the plurality of workpieces is further divided in the first method step and processed, in particular divided, in the second method step. In addition to the first and second method steps, there is a so-called "zeroth" method step in which the workpiece divided in the first method step, in particular the strip divided in the first method step, is first formed from the starting workpiece. This method allows particularly complete division or machining starting from the initial workpiece.

In a third method step following the second method step, the further processing, in particular the splitting, of the first partial workpiece held by the positioning device is carried out in the same direction.

The advantages of the method according to the invention are particularly pronounced when plate-shaped workpieces, in particular initially large-sized plate-shaped workpieces, are to be divided or machined by the method. Such a division or processing takes place, for example, in the production of furniture parts, also for example for kitchen furniture. The plate-shaped workpiece can be made of wood, pressed chip material or plastic material, for example. In principle, however, this method is also possible in other plate-like workpieces, for example metal plates.

The improvement of the invention provides that: in a second method step, the first partial workpiece is positioned for the division of the second partial workpiece such that the region of the second partial workpiece lying adjacent to the first partial workpiece is the final workpiece and the region of the second partial workpiece remote from the first partial workpiece is a reject. Since such waste is usually a narrow strip, the waste can in this case be gripped and cleaned better by the operator.

As an alternative to this, however, in the second method step, for the division of the second partial workpiece, the first partial workpiece can also be positioned in such a way that the region of the second partial workpiece that is adjacent to the first partial workpiece is rejected, while the region of the second partial workpiece that is remote from the first partial workpiece is the final workpiece. This variant is preferred because the stop face of the first workpiece is located closer to the cutting line on the bench.

In the second method step, the first partial workpiece can also be positioned for cutting the second partial workpiece in such a way that the region of the second partial workpiece lying adjacent to the first partial workpiece is the first final workpiece and the region of the second partial workpiece remote from the first partial workpiece is the second final workpiece. This has the advantage that: two final workpieces are produced at once.

Drawings

The invention is described below with reference to the accompanying drawings. In the drawings:

fig. 1 to 23 show top views of a workpiece processing device in the form of a plate dividing device at different points in time during its operation;

fig. 24 shows a flow chart of a method for operating the workpiece processing device of fig. 1 to 23.

Detailed Description

It should be noted here that: for the sake of simplicity, fig. 1 to 23 generally only show reference numerals which are considered to be particularly relevant for understanding the individual figures. It should also be noted here that functionally equivalent elements and regions in the following figures have the same reference numerals.

The workpiece processing apparatus has the reference numeral 10 in general in fig. 1 to 23. The present disclosure relates to a plate-cutting saw similar to the construction substantially known and described in detail, for example, from fig. 2 in german laid-open patent publication DE 102008034050 a1 or from fig. 1 in german laid-open patent publication DE 102015206824 a 1.

The plate dividing saw includes a feed table 12 that is constructed from a plurality of roller rails 14. Connected to the feed table 12 is a machine table 16, which is currently designed as an air cushion table and in which there are saw cuts, which are shown in a simplified manner in the present case as lines with reference numeral 18. Below the machine table 16, there is a saw frame, not visible in the drawings, which is drivable in a driven manner along the kerf 1 and which comprises a motor-driven saw device, preferably with a circular saw blade and a grooving saw (Vorritzer). The circular saw blade and the slitting saw can be moved vertically and can be moved through the kerf 18 above the plane of the machine bed 16. As will be described in more detail below, the workpiece positioned on the table 16 can thus be divided along the kerf 18.

Attached to the machine table 16 is a removal table 20 comprising three sections, which are likewise preferably designed as air cushion tables. For the sake of simplicity, only one section is provided with a reference numeral in the figures. It should also be mentioned that a pressure beam (Druckbalken) is arranged above the machine table 16, but this pressure beam is not shown in the figure. The press beam can be lowered perpendicular to the plane of the machine table 16 by means of a drive, not shown, so that the workpiece located on the machine table 16 is clamped between the machine table 16 and the press beam. Thereby firmly fixing the workpiece during its processing by the saw device described above.

The workpiece processing apparatus 10 also includes a positioning device 22, which currently includes a gantry-type program slide. On the program slide there are a plurality of preferably pneumatically operated clamping jaws 24. The program carriage 22 is mounted so as to be movable by motor drive on the side rails 26, corresponding to the double arrow 28, which double arrow 28 is shown only in fig. 1 for the sake of simplicity.

The workpiece processing device 10 also comprises a control and regulating device 29, which is shown only in fig. 1. The control and regulation means in turn comprise a processor 29a and a memory 29 b. The control and regulating device 29 receives signals from various sensors, not shown, of the workpiece machining device 10. Furthermore, the control and regulating device 29 sends signals to various regulating devices, which are likewise not shown, such as, for example, the drives of the positioning device 22 and of the clamping jaws 24, the drive of the saw device, the drive of the press beam, etc.

As described below, the workpiece machining device 10 can divide the initial workpiece 30 (fig. 1) into a plurality of partial workpieces. The initial workpiece 30 is currently a large-sized board, for example made of pressed chip material, wood, plastic or metal. In principle, it is also conceivable: the initial workpiece 30 is not a single plate but a stack of a plurality of plates.

In a corresponding "zeroth" method step, the initial workpiece 30 is divided into strip-shaped workpieces 32-36 ("longitudinal cut"), and in a corresponding "first" method step into first partial workpieces 38-42 and second partial workpieces 44-50 ("transverse cut"). In a corresponding "second" method step, the second partial workpiece 44 to 50 is machined again, as a result of which a third and final partial workpiece 56 to 62 ("fine cut") is produced, as explained below. The fourth or reject piece produced during each singulation process is generally indicated in the drawings by reference numeral 52. They will not be mentioned in detail in the following description.

In fig. 1, the initial workpiece 30 is positioned relative to the kerf 18 by a positioning device 22 such that a so-called trim cut can be made. This results in a straight edge on the longitudinal edge of the initial workpiece 30.

In fig. 2, the initial workpiece 30 is moved further in the direction of the kerf 18 by the positioning device 22 and positioned in such a way that the first bar-shaped workpiece 32 can be separated.

In fig. 3, the first strip-shaped workpiece 32 has been pushed onto the upper section of the drawing removal station 20. At the same time, the initial workpiece 30 is moved further in the direction of the kerf 18 by the positioning device 22 and positioned in such a way that the second workpiece bar 34 can be separated.

As can be seen in fig. 4: during the initial workpiece 30 being moved again by the positioning device 22 in the direction of the kerf 18, a second workpiece bar 34 is temporarily stored on the two lower sections of the removal station 20. Additional trimming cuts are now made on the other longitudinal edges of the initial workpiece 30, thereby producing a third strip-shaped workpiece 36.

According to fig. 5, a third workpiece bar 36 is also temporarily stored in the two lower sections of the drawing removal table 20. As mentioned above, the production of the three bar-shaped

workpieces

32, 34 and 36 belongs to the "zeroth" method step.

The first bar-shaped workpiece 32 is placed against a measuring angle gauge, not visible in the drawing, which is present in the upper edge of the feed table 12 and of the machine table 16 in the drawing and which is moved in the direction of movement of the positioning device 22 according to the double arrow 28, and is gripped at its left edge in the drawing by the clamping jaws 24 of the positioning device 22 and pulled back onto the feed table 12. The first strip-shaped workpiece is initially positioned in such a way that an edging cut can be carried out, the edge of the strip-shaped workpiece 32 which is directed toward the feed table 12 thereby extending very straight and at right angles to the longitudinal edge of the strip-shaped workpiece 32 and producing a first scrap part 52.

According to fig. 6, the workpiece strip 32 is now divided in a first method step into a first partial workpiece 38 held by the positioning device 22 and a second partial workpiece 44 separated therefrom.

As can be seen from fig. 7, the second part-piece 44 is now rotated by 90 ° about a vertical axis extending perpendicular to the plane of the drawing. At the same time, the first partial piece 38 produced in the first method step continues to be held by the positioning device 22 in the context of the second method step which now begins and is positioned by the retraction to the left in fig. 7 according to the arrow. The edge 63 of the first part-piece 38 facing the removal table 20 can thus now serve as a stop or abutment for positioning the second part-piece 38.

Fig. 8 shows: the second part piece 44 has already been placed against the edge 63 of the first part piece 38 which is directed toward the removal station 20. At the same time, the second part 44 is also placed against the angle gauge already mentioned above but not shown. The second partial workpiece 44 is now machined (this is the second method step) in that the second partial workpiece is divided into a third and final partial workpiece 56 and a fourth partial workpiece, which constitutes the reject 52.

In principle, it is also conceivable: the machining of the second part 44 in the second method step does not or only comprises a division, but alternatively or additionally also comprises the introduction of at least one groove and/or the introduction of at least one hole. For this purpose, appropriate devices, for example milling and/or drilling units, must be present in the workpiece machining device 10.

As can be seen from fig. 8, the first partial workpiece 38 has been positioned by the positioning device 22 such that the region of the second partial workpiece 44 lying against the first partial workpiece 38 is changed into a waste part 52, while the region of the second partial workpiece 44 remote from the first partial workpiece 38 forms a third and final partial workpiece 56.

Fig. 9 shows an alternative positioning of the first part 38 by the positioning device 22: by means of this positioning, the region of the second partial workpiece 44 that bears against the first partial workpiece 38 is the third and final partial workpiece 56, while the region of the second partial workpiece 44 that is remote from the first partial workpiece 38 is the reject 52.

As can be seen in fig. 10: after the second method step, the positioning device 22 is moved in the direction of approaching the saw kerf 18, and the first part piece 38 thereby pushes the already produced third part piece 56 and the reject piece 52 onto the upper section of the removal station 20 in the drawing, so that the third part piece 56 can be removed there by an operator and, for example, stacked, and the reject piece 52 can be cleaned. The first partial workpiece 38 is positioned in such a way that its rear edge can likewise be machined by trimming, thereby producing additional waste parts 52. The trimming cut belongs to a third method step.

In fig. 11, the method described above in connection with the bar-shaped workpiece 32 now starts to be repeated for the bar-shaped workpiece 34: for this purpose, the workpiece strip 34 temporarily stored on the two lower sections of the removal station 20 is pushed, for example by the operator, onto the upper section of the removal station 20 in the figure, aligned with its longitudinal edges on the protractor, gripped by the clamping jaws 24 of the positioning device 22 and pulled back to the left on the feed station 12 in fig. 11. The strip-shaped workpiece is positioned here such that an edging cut can be carried out first, by which a waste piece 52 is in turn produced.

In fig. 12, the workpiece bar 34 is moved by the positioning device 22 toward the kerf 18 and positioned in such a way that a first partial workpiece 40 and a second partial workpiece 46 with an edge 63 are produced (first method step).

The second part 46 is rotated by 90 ° in fig. 13, and the first part 40 is repositioned by means of the positioning device 22.

In fig. 14, the rotated second partial workpiece 46 is placed against the edge 63 of the first partial workpiece 40 (and against a not shown angle gauge) and cut, thereby producing a third and final partial workpiece 58 and a waste part 52 (second method step).

According to fig. 15, the third and final part 58 and the reject 52 are pushed onto the removal table 20 and removed by the positioning device 22 moving in the direction of the removal table 20. Furthermore, the first part piece 40 is repositioned by this movement, so that a further second part piece 48 can be separated (new first method step).

According to fig. 16, the further second part piece 48 is rotated through 90 °, and the first part piece 40 is pulled back and repositioned by the positioning device 22.

As can be seen in fig. 17: the rotated second partial workpiece 48 is placed against the first partial workpiece 40 which is held further by the positioning device 22 and is machined by cutting, whereby a further third and final partial workpiece 60 and a further waste part 52 are produced (new second method step).

Fig. 18 shows: the remaining first partial workpiece 40, which continues to be held by the positioning device 22, is positioned such that an edging cut can be made at the rear edge of this first partial workpiece, thereby producing a further waste piece 52 (third method step).

In fig. 19, the method described above in connection with the bar-shaped workpiece 34 now starts to be repeated for the bar-shaped workpiece 36: for this purpose, the strip-shaped workpiece 36 temporarily stored on the two lower sections of the removal station 20 is pushed onto the upper section of the removal station 20 in the figure, is aligned with its longitudinal edges on the angle gauge, is gripped by the clamping jaws 24 of the positioning device 22 and is pulled back to the left on the feed table 12 in fig. 19. The strip-shaped workpiece is positioned here such that the trimming cut can be carried out first, thereby again producing a waste piece 52.

In fig. 20, the workpiece bar 34 is moved by the positioning device 22 toward the kerf 18 and positioned in such a way that a first partial workpiece 42 and a second partial workpiece 50 with an edge 63 are produced (first method step).

The second part 50 is rotated by 90 ° in fig. 21, and the first part 42 is repositioned by means of the positioning device 22.

In fig. 22, the rotated second partial workpiece 50 is placed against the edge 63 of the first partial workpiece 42 (and against a not shown angle gauge) and cut, so that a third and final workpiece 62 and a waste piece 52 are produced (second method step).

According to fig. 23, the third and final workpiece 62 and the reject 52 are pushed onto the removal table 20 and removed by the positioning device 22 moving in the direction of the removal table 20. Furthermore, the first partial workpiece 40 is repositioned by this movement, so that an edging cut can be carried out, by means of which further waste parts 52 are separated (third method step).

It has already been described above that in the respective second method step the respective second partial piece 44-50 is always machined, i.e. divided, only once to produce the third and final partial piece 56-62 and the respective reject piece. In principle, however, it is also conceivable: in at least one second method step, the respective second partial workpiece 44 to 50 (or the third partial workpiece 56 to 62 produced therefrom) is again machined, for example rotated again and then cut, or machined again by introducing recesses or holes, for which purpose the first partial workpiece 38 to 42 with the edge 63 is in each case repositioned by the positioning device 22 and positioned as required, so that the second partial workpiece 44 to 50 (or the third partial workpiece 56 to 62 produced therefrom) can be brought into abutment against the first partial workpiece 38 to 42 as desired for this further machining process within the second method step.

As can be seen from fig. 24, the above-described flow can in principle also be represented as a flow chart with functional blocks. After starting in block 64, the initial workpiece is divided into first bar-shaped workpieces (longitudinal cuts) in block 66. In a function block 68, it is queried whether further strip-shaped workpieces should be separated from the initial workpiece. If the answer is yes, a jump back to block 66 is made. If the answer is no, then a trim cut is first made in block 70 a. Next, in a functional block 70, a first division is carried out, which divides the resulting first bar-shaped workpiece into a first partial workpiece and a second partial workpiece (transverse cutting, first method step).

A query is then made in a function block 72 as to whether a fine cut should be made on the second part. If the answer is yes, it is queried in a function block 74 whether the second part-piece should be rotated before the fine cutting, taking into account, for example, the texture, the decorative pattern and the included preparation. If the answer is yes, in block 76 the direction and/or angle of rotation is first determined and then the second part is rotated accordingly. The first partial workpiece is then positioned by the positioning device in a function block 78, and the second partial workpiece is placed against the positioned first partial workpiece in a function block 80. The second partial workpiece is then subjected to a fine cut in a functional block 82, so that a third partial workpiece and a fourth partial workpiece (the latter being predominantly waste pieces) are produced (second method step). These workpieces are removed in function block 84.

In a function block 86, it is queried whether additional transverse cuts should be made on the strip-shaped workpiece. If the answer is yes, a jump is made back to before function block 70. If the answer is no, a question is asked in a functional block 88 as to whether further strip-shaped workpieces should be divided by transverse cutting. If the answer is yes, then the process jumps back to block 70 again. Otherwise, the method ends in an end block 90.

The above-described methods are stored as computer programs in the memory 29b of the control and regulating device 29. Which facilitates the design of the control and regulating device 29 for carrying out the above-described method.

Claims

1. Method for machining workpieces, in particular with a plate dividing device (10), wherein in a first method step a workpiece (32-36) is automatically divided into a first partial workpiece (38-42) and at least one second partial workpiece (44-50), and in a second method step the second partial workpiece (44-50) is machined,

characterized in that, in the second method step, the first partial workpiece (38-42) produced in the first method step is automatically positioned as a stop (63) for positioning the second partial workpiece (44-50) for machining the second partial workpiece (44-50), and the second partial workpiece (44-50) is brought into contact with the first partial workpiece (38-42).

2. Method according to claim 1, characterized in that the machining of the second partial workpiece (44-50) in the second method step comprises at least a division into a third partial workpiece (56-62) and a fourth partial workpiece (52) and/or the introduction of at least one groove and/or at least one hole.

3. Method according to any one of the preceding claims, characterized in that the second partial piece (44-50) is rotated, preferably by 90 °, between the first method step and the second method step.

4. Method according to claim 2 or 3, characterized in that the positioning or rotation of the second part piece (44-50) during the second method step is related to the position of the recess and/or the hole.

5. Method according to one of the preceding claims, characterized in that the second partial workpiece (44-50) is machined, in particular divided, a plurality of times in the second method step and for this purpose the first partial workpiece (38-42) is repositioned a plurality of times.

6. Method according to any of the preceding claims, wherein the dividing is performed by using a saw, a milling cutter, a laser cutting device or a water jet cutting device.

7. Method according to one of the preceding claims, characterized in that before the first method step, an initial workpiece (30) is divided into a plurality of workpieces (32-36), in particular by a first cut into a plurality of strips, and then in the first method step at least one of the workpieces is further divided into partial workpieces, in particular by at least one second cut, and in the second method step it is machined, in particular by at least one third cut.

8. Method according to one of the preceding claims, characterized in that the first partial workpiece (38-42) which is held by the positioning device (22) is machined, in particular divided, in a third method step after the second method step.

9. Method according to any one of the preceding claims, characterized in that a plate-shaped workpiece (30-50) is divided or machined by the method.

10. Method according to one of the preceding claims, characterized in that in the second method step, for the division of the second partial workpiece (44-50), the first partial workpiece (38-42) is positioned such that the region of the second partial workpiece (44-50) lying against the first partial workpiece (38-42) is a final workpiece (56-62) and the region of the second partial workpiece (44-50) facing away from the first partial workpiece (38-42) is a reject (52).

11. Method according to one of claims 1 to 9, characterized in that in the second method step, for the division of the second partial workpiece (44-50), the first partial workpiece (38-42) is positioned such that the region of the second partial workpiece (44-50) lying against the first partial workpiece (38-42) is a waste piece (52) and the region of the second partial workpiece (44-50) facing away from the first partial workpiece (38-42) is a final workpiece (56-62).

12. Method according to one of claims 1 to 9, characterized in that in the second method step, the first partial workpiece (38-42) is positioned for the division of the second partial workpiece (44-50) such that the region of the second partial workpiece (44-50) lying against the first partial workpiece (38-42) is a first final workpiece (52) and the region of the second partial workpiece (44-50) facing away from the first partial workpiece (38-42) is a second final workpiece (56-62).

13. Computer program product designed for performing the method according to any of the preceding claims when it is run on a computer.

14. Workpiece processing device (10), in particular a plate dividing device for dividing plate-shaped workpieces, having a positioning device (22) which can position workpieces (32-36), and having a control and regulating device (29) which has a processor (29a) and a memory (29b) and can actuate the positioning device (22), characterized in that the control and regulating device (29) is designed to carry out the following method steps:

a. in a first method step: dividing the workpiece (32-36) into a first partial workpiece (38-42) and at least one second partial workpiece (44-50);

b. in a second method step: positioning the first partial piece (38-42) produced in the first method step by means of the positioning device (22) in such a way that it can serve as a stop (63) for positioning the second partial piece (44-50); and

c. in the second method step: machining the second partial workpiece (44-50).