This invention relates to a method for producing workpieces from a plate-shaped material using a separation procedure in a machine tool.
A 2D laser processing machine is known from WO 2007/137613 A1 which has a workpiece support which comprises several supporting elements that are arranged parallel to one another. Each of these supporting elements comprises bearing point tips arranged at intervals to one another, on which the plate-shaped material is supported. Such contact points between the bearing point tips and the plate-shaped material can negatively affect the workpiece quality during the cutting process, as it can lead to scratching of the supporting side of the plate-shaped material as well as cementing with bearing point tips.
Alternatively to such laser processing machines, so-called sheet mover hybrid systems are already known, in which the plate-shaped material is supported by roller or brush tables, which form a workpiece support. The plate-shaped material is clamped by a gripper unit and is moved relatively to the processing region of the workpiece support with this gripper unit. Such alternative laser processing machines prevent a scratching and, if necessary, cementing of the underside of the plate-shaped material.
Furthermore, a laser processing machine is known from JP 2003290968, in which the plate-shaped material is likewise clamped by a clamp device. The plate-shaped material is supported on a work piece support, which is formed by two workpiece supporting tables, which have deflection rollers pointing towards the cutting gap, which are able to move in and against the X-direction. In this way, the processing region within the laser processing machine does not need to be enlarged due to a movement of the cutting gap, but comprises a constant construction size. The plate-shaped material having the cut workpieces is transferred outwards via an outward transfer belt, which is aligned with the plane of the supporting table.
A further laser processing machine is known from JP 2008200701 A, which has a workpiece supporting surface made from two supporting tables. One of the two supporting tables is arranged in a fixed manner on the base body. The second supporting table, which is adjacent to the cutting gap, can be retracted from the processing region completely into a loading zone. A further supporting table is inserted into the processing region of the laser cutting machine during this, in order to carry out a subsequent processing of the plate-shaped material. A removal of the processed plate-shaped material occurs via the previously retracted supporting table.
WO 2007/003299 A1 describes a machine tool having a workpiece support to support plate-shaped materials for processing with a separating device. This has a processing head which is able to move in at least the Y direction during a separation procedure in the plate-shaped material. The workpiece support comprises a first supporting table having a first supporting surface and a second supporting table having a second supporting surface, whereby the supporting surfaces are at a distance to each other to form a gap underneath the processing head. The position and width of the gap can also be adapted in the processing region of the separating device during the separation procedure.
Furthermore, a machine tool is known from JP 2006192465 A, in which the plate-shaped material is held in a fixed manner by a clamp device and is supplied to a processing head. To produce workpieces, a separating cut is first introduced into the plate-shaped material in a peripheral region pointing towards the processing head, in order to separate the workpiece completely from the plate-shaped material. Subsequently, the supporting surface of the plate-shaped material is lowered, and the plate-shaped material is held in a raised position by the clamp device, such that the workpiece can fall downward. This workpiece is then transported away.
A method is desired for producing workpieces by means of a separation procedure using a separating device in a machine tool, in which the work piece is cut free in a reliable process and an increased productivity is provided.
In one aspect of the invention, a plate-shaped material is supported on supporting surfaces of two supporting tables configured to be arranged with respect to each other to form a cutting gap positioned under the processing head during processing. Separating cuts for waste parts and/or parts of the skeleton are introduced into the plate-shaped material to produce at least one workpiece, such that at least one last separating cut remains for the complete separation of the workpiece(s) from the plate-shaped material, with the waste parts and/or parts of the skeleton being removed through the cutting gap. Subsequently, the workpiece(s) are cut free from the plate-shaped material in such a way that does not involve again moving a cut workpiece over the cutting gap.
In some embodiments the workpiece, which is connected to the plate-shaped material, is supported as far as possible on the second supporting table, if the last separating cut is introduced, such that the workpiece is no longer moved over the gap after it is cut free, but is removed from the gap by the second supporting table and transported away. Thus the catching and tipping of the workpiece can be prevented and a continuous processing of the plate-shaped material is enabled in the X direction.
The method can also provide a reactionless separation and cutting free of work pieces, as well as a separate removal of waste and skeleton parts on the one hand, and work pieces on the other. Thus a high quality of workpieces and a reduction of the work cycles to produce the workpieces are enabled.
In a preferred embodiment of the method, the plate-shaped material is supported on the first supporting table and is positioned with a front-side peripheral region towards the cutting gap, such that, subsequently, separating cuts for waste parts and/or parts of the skeleton are introduced into the front-side peripheral region of the plate-shaped material to produce the at least one workpiece, with at least one last separating cut remaining for the complete separation of the workpiece(s) from the plate-shaped material. Waste parts and/or parts of the skeleton are removed through the cutting gap. The workpiece(s) are cut free and are transported away by the second supporting table. Thus, the plate-shaped material can be continuously processed from one side outwards. Additionally, waste parts and/or parts of the skeleton on the one hand, and the workpieces on the other hand, can be separately removed from the processing region. Thus the danger of them catching on one another is prevented. Additionally, a sorting between waste parts and workpieces can already occur. This method enables the workpieces to be transported away during primary processing time via one of the two supporting tables. After the workpiece(s) are cut free, they are preferably transported away by the second supporting table before the plate-shaped material is processed further. Thus the process reliability is further increased.
Furthermore, the waste parts and/or parts of the skeleton can also be transferred into the unloading zone via the second work table separate from the workpieces. For this purpose, a supporting element of the second work table is preferably powered in order to transfer the individual parts of the skeleton and/or the waste parts from the processing region into an unloading zone, with the workpiece remaining connected to the plate-shaped material via the connecting section for the last separating cut to be introduced. Thus, a separate retraction of the waste parts and/or parts of the skeleton occurs, and this only applies for such parts which are formed without undercuts to the workpiece in the X direction and can be transported away. The plate-shaped material lies stationary on the first supporting table and is preferably held by a clamping device fixed to the processing region.
If the waste parts and/or the parts of the skeleton are exclusively transferred downwards through the cutting gap between the two supporting tables, then this has the advantage that the waste parts and/or the parts of the skeleton, which have an undercut with regard to the direction of transport (in the X direction relative to the workpiece) are transferred downward in a simple way. Subsequently, there is no distinction between waste parts or parts of the skeleton that are free of undercuts or that have an undercut, if all of these parts are transferred downward. Additionally, a continuous production of the workpieces can be enabled. Alternatively, small waste parts can be transferred downward and large parts can be transported away via the further second supporting table as well as, afterward, the workpieces via the second supporting table.
A further preferred embodiment of the invention provides that the workpieces are nested inside strip-shaped sections on the front-side peripheral region pointing towards the cutting gap, and the plate-shaped material is processed to be strip-shaped. This positioning for the nesting of the workpieces enables a movement of the supporting table or the cutting gap towards the processing head to be considerably minimized. Thus the process times can be shortened.
Preferably the nesting of the workpieces is determined such that a mutual last separating cut is introduced into several work pieces within a set width of the cutting gap. Thus, a further optimization can be achieved in the case of the strip-shaped sections, whereby, in particular, the processing head carries out a movement in the Y direction and can separate several workpieces from the plate-shaped material one after the other, which are transported away sequentially. Additionally, a control of the supporting table can be reduced in that preferably a pre-set size of the gap width is fulfilled in order to carry out a mutual separating cut for several workpieces.
Furthermore, preferably in the case of a stationary plate-shaped material arranged in the processing space, the second supporting table moves in the X direction or a supporting element of the second supporting table is powered such that a movement of supporting workpieces occurs in the X direction. Thus a conveyance, in particular a staggered conveyance, of the workpieces from the processing region into an unloading zone can occur after the workpieces are cut free from the plate-shaped material. The individual workpieces that have been cut free can be extracted little by little, preferably by a handling device, in a controlled manner by the supporting table.
In an unloading zone, which, in particular, is adjacent to the second supporting table, a handling device, a storage container or batch container can be positioned. Depending on the further handling steps or integration into an automated assembly line, the workpieces can be handled accordingly. The handling device can remove the workpieces individually from the second supporting table and, for example, position them in an aligned manner in the storage container or transfer them onto a further transport belt, such that a subsequent further processing occurs. Alternatively, the workpieces can also be removed by a universal surface gripper or be deposited into a batch container or storage container directly, originating from the supporting table.
Another aspect of the invention features a method in which separating cuts are first introduced into waste parts that lie within the workpiece or bordering the workpiece. These waste pasts are subsequently transferred downward through the cutting gap between the two supporting tables. The gap between the supporting tables is subsequently set to a gap width smaller than the smallest part size of the workpiece, and then the outer contour of the workpieces is cut at least partially or completely, with the workpieces remaining in the skeleton and being removed from the processing region together with the skeleton. This alternative aspect of the method likewise has the advantage with regard to the production of the workpieces in the throughput time of the plate-shaped material, as a cutting up of the skeleton or the production of the parts of the skeleton for the downward transfer through the cutting gap or a separate transporting away is not necessary.
A preferred embodiment of the method provides that the workpieces, which fall below a critical parts size, are separated from the plate-shaped material by a separating cut to produce the outer contour of the workpieces such that at least one micro joint remains. Thus the workpieces which fall below a critical size, in particular those which have a longitudinal extension smaller than 100 mm, are held in the skeleton by such micro joints and are conveyed out of the processing space together with the skeleton.
Preferably the micro joints are positioned between the workpiece and the skeleton such that these are arranged on the side of the workpiece facing away from the transfer direction. Thus the workpiece must no longer be conveyed over the cutting gap after the micro joint is cut free. After the workpiece has been conveyed substantially over the cutting gap in the direction of the unloading zone, the micro joint is separated during the transfer procedure. Thus the workpiece remains loosely in the skeleton and can be brought into an unloading zone together with the skeleton without again moving over the gap.
A preferred embodiment of the method provides that the plate-shaped material is held in a fixed manner with a clamp in the processing space. Thus, the precise processing of the workpiece is increased, in particular if several separating cuts are required to produce a workpiece.
The invention as well as further advantageous embodiments and developments of the same are described and explained in more detail below by means of the examples depicted in the drawings. The features to take from the description and the drawings can be applied individually or several together in any combination according to the invention.
a to 7f sequentially illustrate individual process steps to carry out the method of
a to 9d sequentially illustrate individual process steps to carry out an alternative method to that in
In
During the cutting of a workpiece 21 from the plate-shaped material 15 using oxygen as a cutting gas, the material of the plate-shaped material 15 is melted and largely oxidized. In the case of the use of inert gases, such as, for example, nitrogen or argon, the material is only melted. The resulting molten particles are then, if necessary, exhausted together with the iron oxides and are sucked up together with the cutting gas via the suction chamber 19 via the suction device 18.
This laser processing machine 11 is controlled via a control 20. A loading zone 24 having a loading device 25 as well as an unloading zone 26 having an unloading device 27 can be provided adjacent to a base body 22 of the laser cutting machine 11.
In
In the case of this embodiment, for example two processing heads 13 are provided instead of only one, which are able to move in the X direction along a processing region 30 via a mutual linear device 29. The processing region 30 is formed over the size of the frame of the base body 22 or is determined by the size of the movement range of the linear unit 29. The linear device 29 has a linear axis in order to move the two processing heads 13 independently in and against the Y direction.
The workpiece support 14 comprises a first and second supporting table 31, 32, which are able to move independently of each other in and against the X direction in the base body 22, and are also able to be positioned outside of the base body 22. According to a first embodiment, it is provided, as is depicted in
The supporting tables 31, 32 can alternatively have rollers or brushes as supporting elements 35 which are likewise powered.
Additionally, an outward transfer element that is not depicted in more detail can be provided, which preferably extends over the width of the processing region 30 or into the width of the supporting tables 31, 32. If necessary, a narrow width is provided in order to receive the outward transfer element within a moveable frame of the supporting tables 31, 32, such that the outward transfer element is able to be arranged as an extract for the extension of the supporting surfaces 38,39 of the supporting tables 31, 32, for example, in order to be moveable, on the one hand completely under the gap 36 and on the other hand in the direction of the loading and/or unloading zone 24, 26, and to form an extension. The outward transfer element can be formed analogically to the supporting table 31, 32.
A transport device 47 is provided underneath the workpiece support 14, for example on the base of the base body 22, in particular as a longitudinal conveyor belt, which extends along the processing region 30. This longitudinal conveyor belt serves to receive waste parts 65 falling through the cutting gap 36 (
Furthermore, a movement unit coupled to the linear device 29 is preferably provided underneath the cutting gap 36, said movement unit carrying a suction hood 48. This suction hood 48, which is part of the suction chamber 19 or forms the suction chamber 19, is connected to the suction device 18. Furthermore, at least one bulk head plate 50 is provided adjacent the gap 36 and, in particular, is able to be set to the position and/or width of the gap 36 to form a shielding of the space extending downward in the base body 22 at the gap 36, into which space the cutting beam 16 enters. Thus, a targeted suction of cutting gas, melting loss, etc., is enabled.
In
A plate-shaped material is introduced into the processing space 30 via the first supporting table 31. For this purpose, the supporting table 31 can be moved into the loading zone 24, so that the loading device 25 deposits a plate-shaped material onto the supporting surface 38 of the supporting table 31. Subsequently, the supporting table 31 is moved again into the processing space. Therein, a movement of the supporting table 31 in the X direction and additionally a drive movement of the supporting element 35 can be provided. The plate-shaped material 15 is gripped and fixed by the clamp device 55 in the processing region 30. At the beginning of a first work step for the method described below, a front-side peripheral region 40 of the plate-shaped material 15 is positioned towards the cutting gap 36 such that the front-side peripheral region 40 lies over the cutting gap 36. There, a front edge 41 of the front-side peripheral region 40 can be supported on the opposite supporting table 32 or can be adjacent a gap-side periphery of the supporting table 32, which is formed by the deflection roller 33 of the second supporting table 32, or can lie partially inside the cutting gap 36. From this starting position, the embodiment variants of the method to produce workpieces described below are described in more detail. Substantially, it is provided that using a continuous supply movement of the plate-shaped material 15 in the X direction, a processing of this plate-shaped material 15 occurs such that there is no repeated moving of the cut workpieces 11 over the cutting gap 36, in order to increase the process reliability in that catching and tipping of the workpieces 21 is prevented. The continuous supply movement of the plate-shaped material 15 can occur using the clamping device 55. Likewise the clamp device 55 can be arranged to be fixed in place in the processing region 30 and the supporting tables shift underneath the plate-shaped material 15 together with the processing head 13, such that cutting gap 36 is carried underneath. Additionally, a combination of the two aforementioned alternatives can also occur in that the clamp device 55 is moved little by little in the X direction and the supporting tables 31, 32 are moved opposed to this accordingly, wherein preferably the supporting elements 35 are powered in order to prevent a relative movement between the supporting element 35, in particular the first supporting table 31, and the plate-shaped material 15.
In
In
In the case of the method illustrated in
This method to produce workpieces is described more precisely below in
Alternatively, the machine tool 11 can be formed according to
In
a shows the positioning of the unprocessed plate-shaped material 15 in a starting position towards the cutting gap 36, as was described in
An alternative embodiment of the method described above can consist in that instead of the process step according to
Furthermore, alternatively to the handling device 56, universal surface grippers can be used, as long as only workpieces 21 are transported away on the supporting table 32. Due to the transfer of the workpieces 21 one after the other via the second supporting table 32, it is furthermore advantageous that both the handling device 56 and a universal gripper do not have to work in the same parts cycle of the workpiece processing.
A further alternative embodiment of the method to produce workpieces 21 from a plate-shaped material is shown in
In
In
According to a first variant of this alternative embodiment of the method, it is then provided that the last separating cut 68 is carried out. As the workpieces 21 are already substantially supported on the second supporting table 32, a tipping and catching is avoided. Additionally, these are no longer transferred back over the cutting gap 36. The separating cuts can be made tightly such that a tipping and catching-free removal of the workpieces from the skeleton 61 is possible. Subsequently, the adjacent strip-shaped section 54 is processed analogously to the process steps described above according to
After the entire plate-shaped material 15 has been processed, the skeleton 61 resulting from this and the workpieces 21 remaining therein are conveyed out of the processing region 30 via the supporting table 32. The workpieces 21 can then be removed via a universal gripper or via a handling device 56. Alternatively, a further sorting device can also be provided in order to separate the workpieces 21 from the skeleton 61, which are deposited in an unloading device 27. Likewise, a mutual depositing of the skeleton 61 and the remaining workpieces 21 in a stack can occur.
A further variant of the alternative embodiment described above provides that the process steps of
Number | Date | Country | Kind |
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10 2011 054 361.9 | Oct 2011 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2012/068283 | 9/18/2012 | WO | 00 | 4/9/2014 |