METHOD FOR ORIENTING TWO WORKPIECES TO FORM A JOINING CONNECTION AND MANIPULATOR
20200156250 ยท 2020-05-21
Assignee
Inventors
Cpc classification
B25J15/0052
PERFORMING OPERATIONS; TRANSPORTING
B25J9/1679
PERFORMING OPERATIONS; TRANSPORTING
G05B2219/50151
PHYSICS
B25J9/1687
PERFORMING OPERATIONS; TRANSPORTING
B25J15/06
PERFORMING OPERATIONS; TRANSPORTING
B23P21/00
PERFORMING OPERATIONS; TRANSPORTING
G05B2219/49299
PHYSICS
International classification
B25J15/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
The invention relates to a method for orientating two workpieces in order to form a joining connection, wherein in a longitudinal orientation step the first workpiece is orientated relative to the second workpiece) along at least one of the workpiece edges by linear movement of at least one of the grippers relative to the other gripper and wherein the longitudinal orientation step is carried out during the transport of the workpieces from the provision station to the processing station. Furthermore, the invention relates to a manipulator which comprises a first gripper and a second gripper.
Claims
1. A method for orientating two workpieces in order to form a joining connection, wherein the method comprises the following steps: introducing or retaining at least two workpieces in a provision station, gripping the first workpiece with a first gripper, gripping the second workpiece with a second gripper, removing the workpieces from the provision station and transporting the workpieces to a processing station, wherein in a longitudinal orientation step the first workpiece is orientated relative to the second workpiece along at least one of the workpiece edges by linear movement of at least one of the grippers relative to the other gripper, and wherein the longitudinal orientation step is carried out during the transport of the workpieces from the provision station to the processing station.
2. The method as claimed in claim 1, wherein prior to the longitudinal orientation step in a transverse orientation step a first movement of the first gripper is carried out in the direction of the second gripper, and/or a first movement of the second gripper is carried out in the direction of the first gripper, wherein there is provision during the movement of the two grippers for the first and the second movement to be carried out simultaneously or successively, and wherein there is provision for the transverse orientation step to be carried out during the transport of the workpieces from the provision station to the processing station.
3. The method as claimed in claim 2, wherein during the transverse orientation step the first workpiece is approached with the first movement against a first stop and uses this stop as a first reference position, and the second workpiece is approached with the first movement against a second stop and uses this stop as a first reference position.
4. The method as claimed in claim 1, wherein after the transverse orientation step in the longitudinal orientation step a second movement of the first gripper in a direction which differs from the first movement and which is non-parallel with the first movement of the first gripper is carried out and/or wherein a second movement of the second gripper in a direction which differs from the first movement and which is non-parallel with the first movement of the second gripper is carried out, wherein there is provision in the event of movement of both grippers for the second movements to be carried out simultaneously.
5. The method as claimed in claim 1, wherein during the longitudinal orientation step during the second movement of the first workpiece the first workpiece is moved against a third stop, and uses this stop as a reference position, and during the second movement of the second workpiece the second workpiece is moved against a fourth stop, and uses this stop as a reference position.
6. The method as claimed in claim 1, wherein, at the beginning of the longitudinal orientation step prior to the second movement of the first workpiece and/or prior to the second movement of the second workpiece, at least one measurement operation is included, wherein in the measurement operation a first reference position on the first workpiece and a second reference position on the second workpiece is detected by means of at least one sensor, preferably one sensor each, and a relative spacing in at least one spatial direction between the first and the second reference position is established and stored.
7. The method as claimed in claim 6, wherein in order to end the longitudinal orientation step at least one movement of one of the grippers for orientating one of the workpieces with respect to a contactless reference mechanism, in particular a sensor or in particular a virtual stop, is carried out.
8. The method as claimed in claim 1, wherein the first gripper and the second gripper are arranged on a common manipulator, preferably on a common multi-axis robot, and are moved in space by this manipulator together from the provision station to the processing station.
9. The method as claimed in claim 1, after the longitudinal orientation step an offset position of the workpieces as a whole is measured and the grippers are displaced during the transfer around the offset position, wherein this displacement around the offset position is superimposed by a transport movement or is carried out in a transport movement pause (idle state).
10. The method as claimed in claim 1, wherein the manipulator when the workpieces are deposited in the processing station corrects a previously measured or calculated offset, preferably in the direction of the x axis.
11. The method as claimed in claim 1, wherein the workpieces after the longitudinal orientation step in the processing station are joined to each other and in particular welded to each other, wherein the welding is carried out in particular by a laser welding method.
12. The method as claimed in claim 1, wherein the workpieces are constructed as planar plates, in particular sheet metal plates and preferably sheet metal plates of different thicknesses and/or different materials.
13. A manipulator comprising a first gripper and a second gripper wherein the manipulator comprises a mechanical stop mechanism, in particular a roller block, wherein the mechanical stop mechanism, in particular the roller block, is arranged between the grippers, wherein the mechanical stop mechanism define a stop edge in the direction toward the first gripper, wherein there is in particular provision for the roller block to comprise in the direction toward the first gripper at least three rollers, which define the stop edge with the running faces thereof, wherein the mechanical stop mechanism define a stop edge in the direction toward the second gripper, wherein there is in particular provision for the roller block to comprise in the direction toward the second gripper at least three additional rollers, which define the stop edge with the running faces thereof, wherein the defined stop edges are orientated parallel with each other, wherein the grippers can each be displaced parallel with the stop edges longitudinally in the direction of an x axis, wherein the grippers can each be displaced transversely relative to the stop edges transversely in the direction of a y axis, and wherein the grippers can be rotated about a vertical axis which is perpendicular to the x direction and the y direction.
14. The manipulator as claimed in claim 13, wherein the grippers are pneumatically driven in the direction of the transversely extending y axis, and/or wherein at least one of the grippers is driven in the direction of the longitudinally extending x axis by a servo motor or a step motor.
15. The manipulator as claimed in claim 13, wherein on the manipulator there is associated with each gripper at least one sensor, in particular a measuring sensor, wherein the sensor is constructed in particular as a surface sensor which monitors a surface, and/or wherein at least one of the sensors is fixed to the manipulator and can be displaced with the manipulator and/or in that at least one of the sensors is a non-displaceable component of the production installation and/or wherein the mechanical stop mechanisms which are in particular constructed as a roller block are divided in two at each stop edge in the longitudinal direction into a first portion and a second portion and the first portion and the second portion are each galvanically separated from each other so that an electrically conductive workpiece which abuts both block portions can be electrically detected.
16. The manipulator as claimed in claim 13, wherein the manipulator comprises a portal carrier, wherein the portal carrier is flange-mounted on the manipulator and wherein the portal carrier is arranged between the manipulator and the two grippers, wherein the roller block is also flange-mounted on the manipulator in such a manner that the manipulator moves the grippers and the roller block together in such a manner that the first gripper moves the first workpiece and the second gripper moves the second workpiece independently of each other relative to the portal carrier and relative to the roller block which is fixed to the portal carrier.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Further details of the present invention will be described in the drawings with reference to an embodiment which is schematically illustrated.
[0040]
[0041]
[0042]
DETAILED DESCRIPTION OF THE INVENTION
[0043]
[0044] The manipulator 2 is used in principle to transport the workpieces 102, 103 from the provision station 3 into the processing station 4, wherein in
[0045] The manipulator 2 comprises a portal carrier 5 which can be displaced on rails 6, 7 along an x axis. The manipulator 2 comprises mechanical stop mechanisms MA which are arranged on the portal carrier 5 between two longitudinal cross-members 8, 9. The mechanical stop mechanisms MA comprise a first stop 10 and a second stop 11, wherein the stops 10, 11 are constructed as transverse stops 12. The longitudinal cross-members 8, 9 can be displaced along a y axis on the portal carrier 5 and carry grippers 13, 14 which can be displaced along the x axis on the longitudinal cross-members 8, 9 and which can each be rotated or pivoted about z axes Z13 or Z14 or vertical axes which are orientated perpendicularly to the drawing plane and orthogonally relative to the x axis and the y axis with respect to the associated longitudinal cross-member 8, 9 in each case and can preferably be lowered and raised in the direction of the associated z axes Z13 or Z14. On the longitudinal cross-members 8, 9 in each case in the direction toward the processing station 4 a sensor 17, 18 is suspended on a retention arm 15, 16. According to a construction variant which is not illustrated, there is provision for the sensor(s) mentioned not to be arranged on the manipulator, but instead to be arranged in a state fixed in the production installation so that the manipulator moves the first plate and/or the second plate during the transport from the provision station to the processing station through a monitoring region of the at least one sensor. Such a construction variant is illustrated schematically in
[0046]
[0047]
[0048]
[0049]
[0050] In
[0051] If the sensors 17, 18 are positioned precisely with respect to each other such that the guiding edges 104b and 105b of the plates 104, 105 now merge smoothly into each other when the plates 104, 105 are pushed together transversely relative to the x axis along the y axis, then the manipulator 2, as indicated by the arrow P10 can move with the plates 104, 105 from the position S5 further into a position S6.
[0052] If there is still an offset between the plates or an offset is intended to be corrected, the plates can be displaced independently of each other and relative to each other by the grippers along the x axis so that the desired orientation of the plates is achieved. Where applicable, it is also sufficient for only one plate to be displaced. Furthermore, there is optionally provision for the method to be carried out in a state monitored by sensors or for a drive of the first gripper and/or a drive of the second gripper to be accordingly controlled in order to move the plate into a desired position. All the displacement movements mentioned can be carried out both whilst the portal carrier of the manipulator is moving and whilst the portal carrier of the manipulator is in an idle state.
[0053]
[0054]
[0055]
[0056]
[0057] According to a construction variant, in the method sequence there is provision for the result of a correction carried out by at least one of the x drives to be controlled by the sensors 217, 218 or additional sensors and where applicable for a further correction, elimination of an offset, to be carried out.
[0058] In principle, it should be noted with regard to the description of the drawings that the snapshots or positions illustrated and described do not necessarily imply that the manipulator and/or the longitudinal cross-members and/or the grippers are in the idle state. The method instead makes provision for the manipulator and/or the longitudinal cross-members and/or the grippers on the way from the provision station into the processing station to move gently and in a jerk-free manner. It is thereby possible for the cycle time to be kept short and disruptive acceleration forces can thereby be prevented.
[0059]
[0060] The sensors 17, 18 and the additional sensors mentioned are preferably constructed as measuring sensors, so-called line sensors, by which the guiding edge of the plates is detected. Alternatively or additionally, there is also provision for reference points and/or the following edge or the rear edge of the plates to be detected. In order to have to carry out the fewest possible adjustment operations, there is also provision to arrange one or more sensors in order to detect an offset and then accordingly to take corrective action when the plates are transferred into the processing station.
[0061] Depending on the geometry of the workpieces or plates, there is provision for the grippers to also be displaced relative to each other in order to minimize displacement times, wherein the relative displacement can be carried out by only one of the two grippers being displaced or the grippers being displaced at different speeds and/or in different directions.
[0062] As a result of the method described, with a corresponding configuration of the components, it is possible for the plates of the tailor-made metal sheet to have an edge offset of +/<0.3 mm.
[0063] In the method sequence, there is also provision in order to maintain a position of the workpiece(s) for the degrees of freedom of the manipulator to be at least partially blocked. In particular, there is provision for at least one of the longitudinal cross-members 8, 9 to be locked on the portal carrier and/or for at least one of the grippers to be locked on the associated longitudinal cross-member in each case with respect to a movement in the direction of the x axis and/or with respect to a lifting movement in the direction of the vertical axis or Z axis thereof.
[0064] As a result of the manipulator, there is a defined depositing of the plates in the processing station or a defined transfer to the processing operation so that in the processing station it is possible to dispense with an additional active orientation of the plates.
[0065]
[0066] The manipulator 502 is used in principle to transport the workpieces 602, 603 from the provision station 503 into the processing station 504. The manipulator 502 comprises a multi-axis robot 502a and a handling device 502b, which is coupled to the multi-axis robot 502a and is moved thereby in space. The handling device 502b comprises a portal carrier 505. The handling device 502b is pivoted by the multi-axis robot 502a from a position 5501 orientated toward the provision station 503 through 270 in a clockwise direction as far as a position S506 orientated toward the processing station 504 about a vertical axis H502a of the multi-axis robot 502a located perpendicularly to the drawing plane. In order to move the handling device 502b from the position S506 into the position S501 again, the multi-axis robot 502a either pivots the handling device 502b further through 90 in the clockwise direction or moves it through 270 back in a counter-clockwise direction. In
[0067] According to a construction variant which is illustrated with broken lines in
[0068] In a similar manner to the first construction variant shown in
[0069] On the path of the handling device 502b from the position S503 into the position S505, the plates 604 and 605 are displaced along the longitudinal cross-members 508, 509 in the direction of the sensors 517, 518, wherein the plates 604 and 605 are displaced with the measuring sensors 517, 518 in such a manner that the guiding edges 504b and 505b of the plates 504, 505 are located in a line and are consequently orientated toward each other without any offset.
[0070] If the production installation 501 is not operated with the sensors 517 and 518, but instead with the sensors 717 and 718, the handling device 502b is moved by the multi-axis robot 502a firstly into the position S505. In this position S505, the plates 604, 605 are then displaced via the sensors 717 and 718 independently of each other in such a manner that the guiding edges 504b and 505b thereof after the displacement are orientated in a line without any offset with respect to each other.
[0071] From the position S505, the handling device 502b is then pivoted by the multi-axis robot 502a into the position S506 via the processing station 504. There, the plates 504, 505 are deposited, pushed together and welded at the longitudinal edges 504a and 505a thereof to form the tailor-made metal sheet 606, whichas shown in
[0072] There is also provision for the manipulator shown in
LIST OF REFERENCE NUMERALS
[0073] 1 Production installation [0074] 2 Manipulator [0075] 3 Provision station [0076] 4 Processing station [0077] 5 Portal carrier [0078] 6, 7 Rail [0079] 8, 9 Longitudinal cross-member [0080] 10 First stop or first transverse stop [0081] 10a Notional stop edge [0082] 11 Second stop or second transverse stop [0083] 11a Notional stop edge [0084] 12 Transverse stop [0085] 13, 14 Gripper [0086] 15, 16 Retention arm for 17, 18 [0087] 17 Sensor [0088] 17a Monitoring region of 17 [0089] 17b Defined position in 17a [0090] 18 Sensor [0091] 18a Monitoring region of 18 [0092] 18b Defined position in 18a [0093] 19 Roller block [0094] 101 Tailor-made component [0095] 102, 103 Workpiece [0096] 104 Plate [0097] 104a Longitudinal edge or workpiece edge to be joined [0098] 104b Guiding edge [0099] 105 Plate [0100] 105a Longitudinal edge or workpiece edge to be joined [0101] 105b Guiding edge [0102] 106 Tailor-made metal sheet [0103] 217 Sensor [0104] 218 Sensor [0105] 251 Carrier unit for 217, 218 [0106] 501 Production installation [0107] 502 Manipulator [0108] 502a Multi-axis robot [0109] 502b Handling device [0110] 503 Provision station [0111] 504 Processing station [0112] 505 Portal carrier [0113] 506, 507 Rail [0114] 508, 509 Longitudinal cross-member [0115] 510 First stop or first transverse stop [0116] 511 Second stop or second transverse stop [0117] 512 Transverse stop [0118] 513, 514 Gripper [0119] 515, 516 Retention arm for 17, 18 [0120] 517 Sensor [0121] 517a Monitoring region of 17 [0122] 518 Sensor [0123] 518a Monitoring region of 18 [0124] 518b Defined position in 18a [0125] 601 Tailor-made component [0126] 602, 603 Workpiece [0127] 604 Plate [0128] 604a Longitudinal edge or workpiece edge to be joined [0129] 604b Guiding edge [0130] 605 Plate [0131] 605a Longitudinal edge or workpiece edge to be joined [0132] 605b Guiding edge [0133] 606 Tailor-made metal sheet [0134] 717 Sensor [0135] 717a Monitoring region of 17 [0136] 718 Sensor [0137] 718a Monitoring region of 18 [0138] 751 Carrier unit [0139] a Coordinate of the guiding edge of the 1st plate [0140] b Coordinate of the guiding edge of the 2nd plate [0141] H502a Vertical axis of 502a [0142] MA Mechanical stop mechanism [0143] V Offset of a and b [0144] VE Displacement plane for 102, 103 and 104, 105 [0145] Z13 z axis of 13 and vertical axis of 13 [0146] Z513 z axis of 513 and vertical axis of 513 [0147] Z14 z axis of 14 and vertical axis of 14 [0148] Z514 z axis of 514 and vertical axis of 514