Machine tool for the punching processing of sheet metal workpieces, in particular for the punching processing of sheet metal

Abstract

Machine tool for the punching machining of sheet metal workpieces, having a punching station with a tool receptacle and a tool magazine (9) with a linear guide (15) and a tool holder (16). The tool holder (16) is provided with a magazine position (18) for a punching tool (22) and is feedable relative to the linear guide (15) along a movement axis on the linear guide (15) of the tool magazine (9). A detection device (27) is in movement connection with the linear guide (15) of the tool magazine (9). The magazine position (18) for the punching tool (22) is feedable into a detection position relative to the detection device (27) in such a way that the tool holder (16) is feedable relative to the linear guide (15) along the movement axis of the tool holder (16). The presence or absence of the punching tool (22) and / or of a tool part of the punching tool (22) in the magazine position (18) for the punching tool (22) that is fed into the detection position can be detected by means of the detection device (27).

Description

TECHNICAL FIELD

[0001] The invention relates to a tool machine for the punching machining of sheet metal workpieces, in particular for the punching machining of sheet metal, having

[0002] a punching station with a tool receptacle, into which punching tools can be exchanged and out of which punching tools can be exchanged, and

[0003] a tool magazine with tool carriers with magazine positions for punching tools and with linear guides for the tool carriers,

[0004] wherein

[0005] the magazine positions provided on the tool carriers are provided with holding means by means of which a punching tool arranged on the magazine position can be detachably fixed to the tool carrier, and

[0006] the tool carriers are guided movably along a movement axis of the tool carriers on the linear guides of the tool magazine and are feedable relative to the linear guides. BACKGROUND

[0007] On known tool machines of the type mentioned at the outset, before the execution of the workpiece machining, the tool magazine is first equipped with the punching tools required for the subsequent machining. In this equipping process, the relevant punching tools are detachably mounted on the tool carriers of the tool magazine. Here, the equipping process can follow a predefined equipping plan, which in its respect prespecifies for the tool magazine the occupancy of punching tools in coordination with the subsequent machining process. Before the punching operation, the punching tools required for the punching operation are exchanged from the relevant magazine positions in the tool magazine into the tool receptacle of the punching station of the tool machine. For this purpose, the tool receptacle of the punching station and the tool magazine are moved relative to one another, in the course of which the punching tools detachably held on the tool carriers of the tool magazine are introduced into the tool receptacle of the punching station and are handed over from the magazine positions of the tool carriers occupied by the punching tools to the tool receptacle. After the end of the punching operation, the punching tools are transferred back from the tool receptacle to the magazine positions of the tool magazine. SUMMARY

[0008] It is the task of the invention to ensure an interference-free process flow.

[0009] According to the invention, this task is solved by a tool machine according to the invention.

[0010] The machine tool according to the application is provided with a detection device which is kinematically connected to the linear guide of the tool magazine, preferably mounted on the linear guide. The tool holder of the tool magazine can be fed jointly with the magazine position for a punching tool relative to the linear guide of the tool magazine along the movement axis of the tool holder. Due to the feed movement, the magazine position reaches into a detection position relative to the detection device. If the magazine position occupies the detection position, the magazine position is accessible to the detection device for a check as to whether a punching tool or a tool part of a punching tool is arranged on the magazine position. In this way, it is possible to check after equipping the tool magazine and also before starting a tool change whether the relevant magazine position of the tool holder is occupied by a punching tool. Subsequently to the change-in process, it is possible to verify by means of the detection device whether the change-in process was successful and thus no punching tool is now located on the previously occupied magazine position of the tool holder.

[0011] By means of a digital evaluation device connected to the detection device, it is possible to compare the results of the detection after equipping the tool magazine with the tool occupancy of the tool magazine stored in the digital control device of the machine tool. Before starting a tool change, it is possible to check whether the tool magazine has been equipped in the manner required for an untroubled progress of the subsequent machining process. If an erroneous occupancy or an erroneous non-occupancy of a magazine position is found when the magazine position is fed into the detection position, the digital evaluation device of the machine control can generate an error message on the basis of which the operating personnel of the machine tool, for example according to the application, is alerted to an equipment error and / or on the basis of which the digital machine control device temporarily prevents the start of an intended tool change.

[0012] Particular embodiments of the machine tool according to the application result from the description.

[0013] According to the structural version of the application, the occupancy of the magazine positions for the punching tools can be detected throughout or at least almost throughout the tool change. Thereby the following possibility is opened: to provide a detection device on the linear guide of the tool magazine for detecting the magazine positions fed into the detection position. If the relative lateral movement of the tool receptacle of the punching station and the tool holder of the tool magazine associated with the tool change is produced by a common active movement of the tool holder and the linear guide of the tool magazine, the detection device simultaneously performs the movement of the magazine position provided on the tool holder and fed into the detection position relative to the detection device and thus can detect the state of the magazine position at least for a longer period of time until the magazine position reaches a position at the tool receptacle, in which it is no longer accessible for the detection device. If the tool receptacle is actively moved along the second movement axis to produce the relative lateral movement of the tool receptacle and the tool holder, the magazine position can also be detected by means of the detection device during the movement of the tool receptacle as long as the magazine position is not shielded by the tool receptacle or the punching station relative to the detection device. The detection position of the magazine position is provided as a zero position of the magazine position for the tool change, that is to say as a position of the magazine position along the movement axis of the tool holder, by means of which position the relative lateral movement of the tool receptacle and the tool holder perpendicular to the movement axis of the tool holder is performed at the tool change.

[0014] In the case of the application, the following possibility exists: to detect the magazine positions of the tool holder with the set occupancy of the complete tool or of the tool parts. According to an advantageous configuration of the application, it is provided that the punching tool has an abstrainer as a tool part and that the presence or absence of the abstrainer can be detected for the magazine positions for the punching tool fed into the detection position.

[0015] The application relates to a machine tool according to the application with a linear magazine as a tool magazine. A plurality of, preferably all, magazine positions of the linear magazine of the machine can be checked for their set occupancy by means of a unique detection device. For this purpose, the magazine positions of the linear magazine can be fed one after the other into a detection position relative to the detection device.

[0016] Different structural versions of the detection device for the machine tool according to the application are conceivable.

[0017] According to the application, a detection device with a transmitter in movement connection with the linear guide of the tool magazine and with a receiver in movement connection with the linear guide is preferred.

[0018] In a further advantageous configuration of the machine tool according to the application, an optical detection device is provided as the detection device. According to the application, sensors with other action principles are also conceivable.

[0019] In the case of the structural version according to the application, the holding portion provided on the linear guide of the tool magazine is used twice: on the one hand for securing the workpiece sensor and on the other hand for mounting at least a portion of the detection device for detecting the magazine position or positions of the tool magazine. It is possible to provide, for example, a sheet arching sensor as workpiece sensor, which is used for detecting the waviness of the sheet to be machined on a sheet- machining machine according to the application. If the machine according to the application has a grating as detection device for detecting the magazine position or positions of the tool magazine, for example a transmitter for detecting the light beam can be mounted on the holding portion of the workpiece sensor.

[0020] In order to be able to adapt the detection device to the respective application case, the detection device can be calibrated with the machine according to the application. For the calibration of the detection device, preferably an adjustment means is used, which ensures that the adjustments made are not changed undesirably under the influence of effects associated with the operation of the machine, in particular vibrations. BRIEF DESCRIPTION OF DRAWINGS

[0021] The application is explained in more detail below on the basis of exemplary schematic drawings. These show:

[0022] Figure 1 : overall view of a machine tool for punching sheet machining,

[0023] Figure 2 : linear magazine of a machine tool according to Figure 1 with magazine positions occupied by punching tools and with a detection device for detecting the magazine positions, and

[0024] Figure 3 : magazine position without punching tool according to Figure 2 . DETAILED DESCRIPTION

[0025] According to Figure 1 , a machine tool 1 for punching sheet machining has an O-shaped machine frame 2. The machine frame 2 is composed of an upper horizontal machine frame side 3, a lower horizontal machine frame side 4, a front vertical machine frame side 5 and a rear vertical machine frame side 6 in the drawing. The machine frame sides 3, 4, 5, 6 delimit a machine interior space 7 of the machine frame 2 with a punching station 8 and a tool magazine 9.

[0026] The punching station 8 has a conventional structural version and has a punch 10 and a die 11 for punching a sheet 12 to be machined. Figure 1A tool receptacle 10 for a punch tool not visible in the drawing. Generally, an upper receptacle 11 of the tool receptacle 10 is arranged on a press ram which, in its turn, can be raised and lowered along a vertical axis 12 on a horizontal machine side 3 above the machine frame 2. A lower receptacle 13 is integrated into a machine table 14 of the tool machine 1 which is supported on a horizontal machine side 4 below the machine frame 2 and can be moved in Figure 1 the drawing partly. The machine table 14 constitutes a workpiece support for (not shown) sheet material.

[0027] The tool magazine 9 of the tool machine 1 is configured as a linear magazine. It comprises a linear guide 15 which is fixedly connected to the machine frame 2 and a tool rack in the form of a cross rail 16 which is guided on the linear guide 15 along a horizontal movement axis 17 and can be moved motor-drivenly.

[0028] The cross rail 16 has a plurality of magazine positions 18 which are arranged on the cross rail 16 offset from one another along the movement axis 17. Furthermore, the cross rail 16 is provided with a plurality of clamping jaws 19 which are generally used for fixing sheet material on the cross rail 16.

[0029] For punch machining, the sheet material held on the cross rail 16 by means of the clamping jaws 19 and the punch station 8 with the punch tool exchanged into the tool receptacle 10 are moved relative to one another in two-axial machining movements which are carried out in a horizontal plane. In order to generate the two-axial machining movements, on the one hand, the cross rail 16 with the sheet material fixed thereon is moved along the movement axis 17 in the direction of the double arrow shown in Figure 1 the drawing relative to the linear guide 15. Furthermore and especially superimposed therewith, the tool receptacle 10 together with the punch tool received therein is moved along a second movement axis 20 in the direction of the double arrow likewise shown in Figure 1 the drawing.

[0030] The movement axis 17 of the cross rail 16 constitutes the X axis of the coordinate system of the numerical control device 21 of the tool machine 1 which is strongly schematically shown in Figure 1 the drawing, the second movement axis 20 of the tool receptacle 10 constituting the Y axis thereof.

[0031] The possibilities existing on the tool machine 1 for generating machining movements during sheet material machining are also used for exchanging punch tools on the tool receptacle 10.

[0032] Before the start of sheet material machining, the tool magazine 9 is first equipped. For this purpose, the punch tools are manually installed on selected magazine positions 18 of the cross rail 16 in accordance with a predefined equipping plan. A magazine position 18 with a punch tool 22 is shown in Figure 2 the drawing.

[0033] The punching tool 22 generally comprises as tool parts a punching punch 23, a stripper 24 and a punching bottom die 25. The punching punch 23, the stripper 24 and the punching bottom die 25 are detachably accommodated in a conventional tool magazine 26 serving as a holding device, which in its turn is detachably pushed into a receptacle on the transverse rail 16 of the tool magazine 9 at the associated storage location 18.

[0034] In Figure 2 the detection device 27 is also shown, which in the case of the embodiment shown is configured as a grating, in particular as a reflective grating.

[0035] The sender / receiver unit 28 of the detection device 27 is shown in Figure 2 with a light source 29 as sender and a light receiver 30 for detecting the light beam.

[0036] Figure 3 The reflector 31 of the detection device 27 is shown in Figure 2 with the detection light beam 32 passing between the sender / receiver unit 28 and the reflector 31 and being broken in .

[0037] The detection device 27 is fitted on the linear guide 15 of the tool magazine 9. For attaching the sender / receiver unit 28 of the detection device 27 to the linear guide 15, a holding part 33 for a workpiece sensor 34 is used here. The holding part 33 is configured as a holding arm projecting from the linear guide 15. The reflector 31 of the detection device 27 is fastened in a similar manner on the linear guide 15 of the tool magazine 9. In the case of the embodiment shown, a sheet metal camber sensor is provided as workpiece sensor 34.

[0038] After equipping the tool magazine 9, first of all the storage locations 18 which are to be occupied by punching tools 22 according to the equipping plan are arranged in succession in a detection position relative to the detection device 27. Here, the transverse rails 16 are fed relative to the linear guide 15 and relative to the detection device 27 connected to the linear guide 15 along the movement axis 17. By means of the detection device 27 it is checked whether the storage locations 18 moved into the detection position are occupied by punching tools 22 in accordance with the equipping plan.

[0039] For this purpose, the detection light beam 32 is emitted from the light source 29 of the detection device 27 in the direction of the reflector 31. The positions of the sender / receiver unit 28 of the detection device 27 and the reflector 31 are chosen such that the detection light beam 32 emitted from the light source 29 is interrupted as soon as a punching tool 22 with a stripper 24 is arranged on a storage location 18 located in the detection position.

[0040] In Figure 2The positive detection result is shown in Fig. 6. The detection light beam 32 emitted from the light source 29 of the detection device 27 hits the reflector 31 and is reflected by the reflector film of the reflector 31 to the light receiver 30 of the transmitting / receiving unit 28. In this case, based on the detection result, an error message is generated by the evaluation device of the numerical control device 21 of the machine tool 1, based on which the machine tool operator is informed of the erroneous occupancy of the cross rail 16 of the tool magazine 9 and the start of the intended machining process is prevented.

[0041] Figure 3 A case of application is shown in which the punch tool 22 is not arranged on the magazine place 18 fed into the detection position by oversight or the extractor 24 is not arranged. The detection light beam 32 emitted from the light source 29 of the detection device 27 reaches the reflector 31 and is reflected by the reflector film of the reflector 31 to the light receiver 30 of the transmitting / receiving unit 28. In this case, based on the detection result, an error message is generated by the evaluation device of the numerical control device 21 of the machine tool 1, based on which the machine tool operator is informed of the erroneous occupancy of the cross rail 16 of the tool magazine 9 and the start of the intended machining process is prevented.

[0042] If the check of the magazine places 18 of the cross rail 16 carried out by means of the detection device 27 leads to a positive result, the punch tool 22 first required in the subsequent machining process is exchanged from the tool magazine 9 into the tool receptacle 10 of the punching station 8.

[0043] Here, the cross rail 16 of the tool magazine 9 is moved along the movement axis 17 relative to the linear guide 15 into a position in which the punch tool 22 and its magazine place 18 are located in a so-called zero position relative to the linear guide 15. In this zero position, the punch tool 22 on the cross rail 16 is opposite the tool receptacle 10 along the second movement axis 20. The zero position of the punch tool 22 is at the same time the detection position of the magazine place 18 in which the punch tool 22 is located.

[0044] When the punch tool 22 is arranged in the zero position and the detection device 27 is switched on, the punching station 8 with the tool receptacle 10 carries out a movement along the second movement axis 20 oriented towards the tool magazine 9 until the punch tool 22 enters the tool receptacle 10 of the punching station 8.

[0045] During the relative lateral movement of the tool receptacle 10 and the cross rail resulting from the movement of the tool receptacle 10 along the second movement axis 20, the detection device 27 detects the punch tool 22 or the extractor 24 arranged on the relevant magazine place 18.

[0046] If the punch tool 22 or the extractor 24 leaves the detection position during the relative lateral movement of the tool receptacle 10 and the cross rail 16 as a result of an irregular event and if the detection light beam 32 emitted from the detection device 27 therefore reaches the light receiver 30 of the transmitting / receiving unit 28, the numerical control device 21 of the machine tool 1 causes the interruption of the tool exchange.

[0047] If the relative lateral movement of the tool receptacle 10 and the lateral rail 16 is not interrupted and it can therefore be concluded that the associated punching tool 22 has been exchanged into the tool receptacle 10 as intended, the tool receptacle 10 is moved back from the lateral rail 16 along the second movement axis 20 in the first instance with the detection device 27 switched off. Along the movement axis 17 of the lateral rail 16, the storage location 18 for the punching tool 22, which is now exchanged into the tool receptacle 10, is always fed into the detection position relative to the detection device 27.

[0048] As soon as the tool receptacle 10 is at a distance from the storage location 18 along the second movement axis 20 at which the storage location 18 is again accessible to the detection beam 32 of the detection device 27, the detection device 27 is switched on and checks whether the storage location 18 is actually empty by emitting the detection beam 32 and whether the exchange of the tool into the tool receptacle 10 of the punching station 8 preceding this has actually been successful accordingly.

[0049] The exchange of the punching tool 22 out of the tool receptacle 10 of the punching station 8 takes place accordingly. After the punching tool 22 to be exchanged out of the tool receptacle 10 of the punching station 8 has been transferred to the associated storage location 18 of the lateral rail 16, which is moved into the detection position relative to the linear guide 15, as soon as the storage location 18 and the tool receptacle 10 are sufficiently far apart from one another as a result of the corresponding movement of the tool receptacle 10 along the second movement axis 20, the occupancy of the storage location 18 is checked by means of the detection device 27. If the detection beam 32 emitted from the light source 29 of the detection device 27 towards the storage location 18 is interrupted, this indicates that the punching tool 22 has been successfully removed from the tool receptacle 10 of the punching station 8. If the detection beam 32 emitted from the light source 29 of the detection device 27 towards the storage location 18 is reflected to the light receiver 30, the storage location 18 is erroneously empty and must have resulted from the fact that the tool exchange process has not led to the desired result.

[0050] Each of the punching tools 22 loaded in the framework of the machining process is moved in the manner described above when being exchanged in and out.

Claims

1. A machine tool for punching machining of sheet metal workpieces, having: a punching station (8) with a tool receptacle (10) onto which a punching tool (22) can be exchanged in and out of, and a tool magazine (9) with a tool carrier (16) and a linear guide (15) for the tool carrier (16), the tool carrier having a storage location (18) for the punching tool (22), wherein the storage location (18) provided on the tool carrier (16) is provided with a holding device by means of which the punching tool (22) arranged on the storage location (18) can be detachably fixed on the tool carrier (16), and the tool carrier (16) is movably guided on the linear guide (15) of the tool magazine (9) along a movement axis (17) of the tool carrier (16) and can be fed relative to the linear guide (15), characterized in that a detection device (27) is provided, which is in movement connection with the linear guide (15) of the tool magazine (9) and into which the storage location (18) for the punching tool (22) can be fed relative to the detection device into a detection position in such a way that the tool carrier (16) can be fed relative to the linear guide (15) along the movement axis (17) of the tool carrier (16), wherein the presence or absence of a punching tool (22) and / or a tool part of the punching tool (22) in the storage location (18) for the punching tool (22) fed into the detection position can be detected by means of the detection device (27), the detection position of the storage location (18) being provided as a zero position of the storage location (18) for tool exchange, the zero position being a position of the storage location (18) along the movement axis (17) of the tool carrier (16) by means of which a relative lateral movement of the tool receptacle (10) and the tool carrier (16) perpendicular to the movement axis (17) of the tool carrier (16) is carried out when exchanging tools. The machine tool is used for punching sheet metal machining.

3. The machine tool according to claim 1, characterized in that: the tool receptacle (10) and the tool carrier (16) of the tool magazine (9) can be moved relative to one another with a relative lateral movement along a second movement axis (20) extending perpendicular to the movement axis (17) of the tool carrier (16) when exchanging the punching tool (22) into the tool receptacle (10) of the punching station (8) and / or when exchanging the punching tool (22) out of the tool receptacle (10), the storage location (18) for the punching tool (22) is fed relative to the linear guide (15) of the tool magazine (9) into the detection position during the relative lateral movement of the tool receptacle (10) and the tool carrier (16), and the detection device (27) is designed in such a way that the detection device (27) is in movement connection with the linear guide (15) of the tool magazine (9) and into which the storage location (18) for the punching tool (22) can be fed relative to the detection device into a detection position in such a way that the tool carrier (16) can be fed relative to the linear guide (15) along the movement axis (17) of the tool carrier (16), wherein the presence or absence of a punching tool (22) and / or a tool part of the punching tool (22) in the storage location (18) for the punching tool (22) fed into the detection position can be detected by means of the detection device (27), the detection position of the storage location (18) being provided as a zero position of the storage location (18) for tool exchange, the zero position being a position of the storage location (18) along the movement axis (17) of the tool carrier (16) by means of which a relative lateral movement of the tool receptacle (10) and the tool carrier (16) perpendicular to the movement axis (17) of the tool carrier (16) is carried out when exchanging tools. ​ ​ ​ ​ ​ 2. Machine tool according to claim 1, characterized in that ​ ​ ​ ​ • the presence or absence of a punch tool (22) and / or a tool part of the punch tool (22) can be detected for the magazine location (18) for the punch tool (22) fed into the detection position by means of the detection device (27) during the relative transverse movement of the tool receptacle (10) and the tool carrier (16).

4. Machine tool according to any one of claims 1 to 3, characterized in that The punch tool (22) has a stripper (24) as a tool part, and the presence or absence of the stripper (24) can be detected for the magazine location (18) for the punch tool (22) fed into the detection position.

5. Machine tool according to any of claims 1 to 3, characterized in that • the tool magazine (9) is designed as a linear magazine in such a way that a plurality of magazine locations (18) are provided on the tool carrier (16) which are offset from one another along the movement axis (17) of the tool carrier (16), • each of the magazine locations (18) can be fed into a detection position in such a way that the tool carrier (16) can be fed relative to the linear guide (15) along the movement axis (17) of the tool carrier (16), and • the presence or absence of a punch tool (22) and / or a tool part of the punch tool (22) can be detected for each of the magazine locations (18) fed into the detection position by means of the detection device (27).

6. Machine tool according to any one of claims 1 to 3, characterized in that The detection device (27) has a transmitter which is in movement connection with the linear guide (15) of the tool magazine (9) and a receiver which is in movement connection with the linear guide (15).

7. Machine tool according to any of claims 1 to 3, characterized in that An optical detection device (27) is provided as the detection device (27).

8. Machine tool according to claim 6, characterized in that • a grating is provided as the optical detection device (27) with a light source (29) which is in movement connection with the linear guide (15) of the tool magazine (9) as a transmitter for a detection light beam (32) and with a light receiver (30) which is in movement connection with the linear guide (15) for the detection light beam (32), and • the magazine location (18) for the punch tool (22) fed into the detection position is arranged at least in the range of a region of a tool part belonging to the punch tool (22) in the light path of the detection light beam (32).

9. Machine tool according to claim 8, characterized in that A reflective grating is provided as the grating, the light source (29) and the light receiver (30) of which are in movement connection with the linear guide (15) of the tool magazine (9) on the side of the magazine location (18) for the punch tool (22) or on the side of the region of the magazine location (18) belonging to the tool part of the punch tool (22), and the reflective grating further comprises a reflector (31) which is in movement connection with the linear guide (15) on the side of the magazine location (18) or of the region of the magazine location (18) belonging to the tool part of the punch tool (22) which is remote from the light source (29) and the light receiver (30).

10. Machine tool according to any one of claims 1 to 3, characterized in that • the linear guide (15) of the tool magazine (9) is provided with a holding portion (33) for a workpiece sensor (34), and • the probe device (27) is at least partially mounted on the holding portion (33) for the workpiece sensor (34).

11. Machine tool according to any of claims 1 to 3, characterized in that The probe device (27) is connected to the linear guide (15) of the tool magazine (9) in a manner that is alignable relative to the linear guide (15).

Images