Transport device for press lines and method for controlling such a transport device

Abstract

A transport device for the transport of workpieces in a workpiece transport direction in a press, which has a carrier rail, which is mounted, via a lifting carriage and a rocker rotatably mounted on the lifting carriage, on a vertically running upright of the press. In order to enable a flexible workpiece transport, it is provided that, on the carrier rail, workpiece grippers are mounted on at least two transport carriages, which each have their own drive mechanism in order to move the transport carriages with the workpiece grippers along the carrier rail independently of each other.

Claims

1. A transport device for transporting workpieces in a workpiece transport direction through a forming area in a forming machine or a pressing area of a press line, the transport device comprising a gate area arranged on a lateral side of the pressing area or forming area bordered by two vertical uprights having a carrier rail running in the workpiece transport direction, wherein each end of the carrier rail is mounted on one of the vertically running uprights, via a lifting carriage displaceably driven in the vertical direction by a lift drive, and the lifting carriage rotatably mounts a rocker, an end of the rocker being connected to the carrier rail, wherein the length of the carrier rail is shorter than the distance between the vertical uprights in the workpiece transport direction and the rocker is rotatably mounted on the lifting carriage in such a way that the carrier rail can be pivoted out of the pressing area or forming area in that the carrier rail can be pivoted between the two vertical uprights into the gate area or through the gate area.

2. The transport device according to claim 1, wherein the lifting carriage has a rotary drive for rotating the rocker and wherein the rotary drive has a rotary output which co-operates with a carriage-side pivot bearing for rotating the rocker.

3. The transport device according to claim 1, wherein the angle between the rocker and the vertical upright connected to the rocker is within an angular range of 0° to 10°, when the carrier rail is located in the gate area.

4. The transport device according to claim 1, wherein the carrier rail has a transport carriage with an exchangeable workpiece gripper.

5. The transport device according to claim 1, wherein, on the carrier rail, at least two transport carriages each having a workpiece gripper are mounted, wherein each transport carriage has a drive mechanism in order to move this transport carriage in a driven manner along the carrier rail independently of other transport carriages.

6. The transport device according to claim 1, wherein the rocker has a single rocker arm connecting the carrier rail to the lifting carriage, wherein the rocker arm is pivotably connected to the carrier rail.

7. The transport device according to claim 1, wherein the end of the rocker connected to the carrier rail has a bracket for the detachable connection of the carrier rail, wherein the bracket has a detachable mechanical connection and a detachable electrical connection.

8. The transport device according to claim 7, wherein the rocker has a pivot drive, which pivots the carrier rail and/or the bracket relative to the rocker in order to set a particular angle between the carrier rail and the rocker.

9. The transport device according to claim 7, wherein, on the end of the rocker connected to the carrier rail at the bracket, the rocker has a longitudinal drive in order to move the carrier rail in the workpiece transport direction.

10. The transport device according to claim 9, wherein the longitudinal drive is an electric linear motor having a stator arranged on the rocker or the bracket and a rotor arranged on the carrier rail, or wherein the rotor is arranged on the rocker or the bracket and the stator is arranged on the carrier rail.

11. The transport device according to claim 1, wherein the lift drive of the lifting carriage is formed as a linear motor.

12. The transport device according to claim 1, wherein the lifting carriage or the lift drive of the lifting carriage has a switchable locking mechanism in order to fix the lifting carriage in a vertical position on a vertical upright.

13. The transport device according to claim 1, wherein the lift drive and a rotary drive of the lifting carriage are connected to a control device and the control device is configured to actuate both the lift drive and the rotary drive for performing a clamping movement of the carrier rail.

14. The transport device according to claim 1, wherein the lift drive and a rotary drive and a pivot drive are connected to a control device and the control device is configured to actuate the lift drive as well as the rotary drive and the pivot drive for performing a clamping movement of the carrier rail.

15. The transport device according to claim 13, wherein the carrier rail has a longitudinal drive connected to the control device and the control device actuates the longitudinal drive for moving the carrier rail in the workpiece transport direction or contrary to the workpiece transport direction, in order to transport workpieces.

16. The transport device according to claim 1, wherein the vertical uprights are formed as press uprights.

17. The transport device according to claim 1, wherein two of the carrier rails running in the workpiece transport direction are provided, wherein each end of the two carrier rails is mounted on a respective one of the vertically running uprights via a respective one of the lifting carriages.

18. The transport device according to claim 1, wherein the lifting carriages are arranged in the lateral gate area, wherein one lifting carriage is mounted on a respective one of the vertical uprights each in such a way that the lifting carriages are arranged on the directly opposite ends of two vertical uprights.

19. A press line comprising a press bed and four press uprights, wherein two of the press uprights are arranged on one side of the press bed each, spaced apart from each other in the workpiece transport direction, and wherein wherein the press line further comprises a transport device according to claim 1 secured to the press uprights.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantageous designs of the invention are shown in the figures and described in the following description of the figures.

(2) There are shown in:

(3) FIGS. 1a, 1b: the transport device with a press line,

(4) FIG. 2: a schematic top view of a variant of the press line with transport device,

(5) FIGS. 3a, 3b: a detailed representation of a variant of the transport device in the area of a lifting carriage,

(6) FIGS. 4a, 4b: a detailed representation of an alternative variant of the transport device in the area of a lifting carriage,

(7) FIG. 5: a schematic representation of a turning circle of a lifting carriage,

(8) FIGS. 6a, 6b: a schematic representation of a lifting movement of a variant of the transport device in the area of a vertical press upright.

DETAILED DESCRIPTION OF THE INVENTION

(9) In FIGS. 1 to 6b different embodiments of the invention are represented. Essentially, the structures of the individual designs agree. Differences between the embodiments are explained in each case in the description of the figures. The same components are, in each case, provided with the same reference numbers.

(10) In FIGS. 1a and 1b, a press line (or forming machine) 1 is shown. The press line 1 has a transport device 2 in order to transport workpieces in the workpiece transport direction W. The press line 1 has a press base 12 at the bottom on which a press bed 11 is arranged. The press bed 11 is arranged in the centre of the working area of the press. The press line 1 has four vertically running press uprights 13a, 13b, 13c and 13d. The press uprights 13a to 13d are formed as supporting profiles and arranged in the area of the corners of the press base. The press uprights stand on the base 12 of the press line 1 and support a press cross-head. A press die with a pressing tool is secured to the press cross-head. In the figures, for the purposes of better clarity, the press cross-head with the press die and the pressing tool is not shown.

(11) The transport device 2 has two carrier rails 21 and 22 running in the workpiece transport direction. Each carrier rail 21 or 22 is mounted, in the area of their ends, on a vertical press upright 13a to 13d by means of a rocker 36 and a lifting carriage 3.

(12) Several transport carriages 24 are arranged on each carrier rail 21 or 22. The transport carriages 24 can be moved relative to the carrier rail 21 or 22. For this purpose, the transport carriages 24 each have a drive mechanism 241 which has an electric linear motor 242 in order to move the transport carriages 24 along the carrier rail 21 or 22 in a driven manner. The drive mechanisms 241 can be actuated selectively via a control device 40, i.e. each transport carriage can be actuated or moved independently. The transport carriages 24 each have a tool gripper 25. The tool grippers 25 are each detachably mounted on a transport carriage and can be exchanged easily. With the aid of the tool grippers, individual workpieces can be received and subsequently processed in the press. After the processing procedure, the workpiece is transported out of the pressing area and transferred to the next processing station.

(13) The two carrier rails 21 and 22 are each connected to lifting carriages 3 via rockers 36. The lifting carriages 3 have a lifting bracket, which is secured to a vertically running rail 32. The vertically running rail 32 is each connected to a vertical press upright 13a to 13d. The lifting carriage 3 can be moved in the vertical direction, i.e. up or down, on the vertical press upright 13a to 13d via a lift drive 31. In this movement, the respective carrier rail 21 or 22 is carried along with the result that the carrier rail can be adjusted in the vertical direction via the lifting carriage 3. The lifting carriage 3 has a lifting motor 33, which acts between the lifting carriage and lift rail, in order to move the lifting carriage along the rail 32. The lifting motor 33 can be formed as an electric servomotor, or as a stepper motor or as an electric linear motor.

(14) In order also to be able to absorb high mechanical forces via the transport device, in one design, as shown in FIG. 31, it can be provided that the lifting carriage or the lift drive of the lifting carriage has a switchable locking mechanism 41 in order to fix the lifting carriage in a vertical position on the upright. The locking mechanism can, for example, comprise a bolt which can be moved via a solenoid, which fixes the lifting carriage on the vertical upright in that the bolt engages in a recess. Alternatively, the locking mechanism can comprise a clamp which can be switched via an electromagnet, which clamps the lifting carriage in a vertical position on the upright. Alternatively, hydraulic or pneumatic locking mechanisms can also be provided in order to fix the lifting carriage in a vertical position on an upright.

(15) The rocker 36 is rotatably mounted on the lifting carriage 3. Between the rocker 36 and the lifting carriage 3 a rotary drive 34 is arranged for this purpose, by means of which the rocker 36 can be rotated relative to the lifting carriage 3. The rotary drive 34 has a rotary motor 341, which can be formed as an electric servomotor or as a stepper motor. In FIG. 5, a turning area of a rotary drive 34 is represented by way of example.

(16) At its end facing away from the lifting carriage 3, the rocker 36 is connected to a carrier rail via a bracket 38. In the area of the bracket, a longitudinal drive 39 is arranged, which drives the carrier rail in the longitudinal direction, i.e. in the workpiece transport direction W. Via the longitudinal drive 39, the carrier rail 21 or 22 can be moved in the workpiece transport direction W or contrary to the workpiece transport direction W.

(17) The bracket 38 for connecting a carrier rail is optional. In one design not represented in the figures, the carrier rail can be secured directly, i.e. without an intermediary bracket, to the rocker.

(18) The longitudinal drive 39 is also optional. In one design not represented in the figures, the carrier rail can be formed without a longitudinal drive. In this case, the carrier rail cannot be moved in the workpiece transport direction. A workpiece transport in the workpiece transport direction takes place in this case solely via the transport carriages.

(19) In FIG. 2 a top view onto the press line 1 is represented. In this representation, the range of movement of the transport rails in the workpiece transport direction W is outlined. In the representation of FIG. 2, a press input window F1 is represented in the upper area. In this area, workpieces or raw material are transferred to the press line 1. For this purpose, the two carrier rails 21 and 22 each are moved via the longitudinal drive 39 contrary to the workpiece transport direction W with the result that they extend into the press input window F1. There, a workpiece or raw material can now be received via workpiece grippers 25.

(20) As represented in FIGS. 1a and 1 b, the workpiece grippers 25 are movably mounted via transport carriages 24 on the carrier rails 21 and 22. This enables additional flexibility in that, not only can the carrier rails 21 and 22 be moved in the workpiece transport direction W, but in addition the transport carriages 24 and the workpiece grippers 25 respectively can also be moved in the workpiece transport direction W or contrary to the workpiece transport direction W, respectively.

(21) In an alternative variant, which is not represented in the figures, it can be provided that the workpiece grippers are held directly on the carrier rail 21 or 22 via fixed holders. In this case, the workpiece transport takes place solely through the longitudinal drive 39 of the carrier rails 21 or 22.

(22) After the workpieces have been received in the press input window F1, they are moved in the workpiece transport direction W into the pressing area. There, the workpiece can be processed. Subsequently, the workpiece can be moved via the longitudinal drive 39 and/or the transport carriages 24 into the output press window F2. In the output press window F2, the processed workpiece can be removed or supplied to a further processing station.

(23) In the variants represented in FIGS. 1a and 1 b, with the transport carriages 24 movably mounted on the carrier rails 21 and 22, advantageously not only one workpiece can be taken over in the press input window F1. In addition, by selective actuation of the transport carriages 24, another workpiece can be taken over in the press output window F2. Subsequently, the transport carriages 24 can be moved, contrary to the workpiece transport direction W, into the pressing area together with the workpiece taken over in the press output window F2. This makes it possible for two workpieces to be processed in parallel in the pressing area. Alternatively, it can be provided that the two workpieces can be joined to each other in the pressing area. Subsequently, the workpieces can be transported out of the pressing area by actuating the transport carriages 24 in the workpiece transport direction and there removed or transferred to a further processing station.

(24) The longitudinal drive 39 can be formed as an electric linear motor, as represented in FIG. 1a. The stator of the electric linear motor is arranged on the rocker 36 or a bracket 38. The rotor of the electric linear motor is arranged on the carrier rail 21 or 22, respectively and connected to the carrier rail and can be moved relative to the rocker 36 in the workpiece transport direction W.

(25) In an alternative design, as represented in FIG. 1a, the longitudinal drive 39 can have a drive motor 391 co-operating with a toothed rack 392, in order to drive the carrier rails 21 or 22 in the workpiece transport direction W.

(26) In an alternative design, the longitudinal drive can also have a toothed belt drive or a spindle drive.

(27) In a simple design, the transport device 2 can also have carrier rails 21 and 22, which are connected directly, i.e. without a longitudinal drive 39, to the rocker 36. In this variant, the workpiece transport takes place solely via the individually actuatable transport carriages 24. During the transfer of workpieces or raw material in the area of the press window F1 or F2, in this variant, the workpieces are transported into the press window or transported out of the press window with a separate handling device.

(28) The carrier rails 21 and 22 are pivotably connected to the rocker 36. In FIGS. 1a, 1b as well as in FIGS. 2, 3a, 3b and 5, a pivot drive 37 is provided on the end of the rocker 36 each, in order to pivot the carrier rail relative to the rocker. With the aid of this pivot drive 37, the carrier rail can be aligned relative to the rocker 36, for example be pivoted into a horizontally running position.

(29) In FIGS. 4a and 4b, as well as 6a and 6b, an embodiment is shown in which the rocker 36 is formed as a parallel guide and has two rocker arms 361 and 362. Via this parallel guide, in this design the attached carrier rail 21 or 22 always has a horizontally running position.

(30) The transport device 2 can move the carrier rails preferably in or contrary to the workpiece transport direction W, and transverse to the transport direction, i.e. in the clamping direction and vertically, i.e. in the lifting direction. A clamping movement, i.e. a movement transverse to the workpiece transport direction can take place through a combined actuation of the rotary drive 34 and the pivot drive 37 as follows. The rocker 36 is rotated via the rotary drive 34. Through the rotational movement, the carrier rail 21 or 22 realizes a first movement component transverse to the workpiece transport direction and a second movement component in the vertical direction. The movement component in the vertical direction is compensated by contrary actuation of the lifting carriage 3 with the result that the height of the carrier rail 21 or 22 remains unchanged. At the same time, the alignment of the carrier rail 21 or 22 is corrected via the pivot drive 37 or the parallel guide of the rocker 36 with the result that an alignment of the carrier rail 21 or 22 is not changed by the rotational movement. In this way, it is possible to perform a linear horizontal movement in the clamping direction with the carrier rails which are rotatably mounted via the rocker 36. The pivot drive 37, the rotary drive 34, as well as the lift drive 3 are actuated via a control device which is connected to the pivot drive 37, the rotary drive 34 and the lift drive 31 respectively.

(31) The rocker 36 rotatably mounted on the lifting carriage 3 can be formed, in a variant, as a one-piece rocker 36, as represented for example in FIGS. 3a and 3b. In this variant, the rocker 36 is rotatably connected to the lifting carriage 3 with one end via a pivot bearing. In the area of the pivot bearing, a rotary drive motor 341 of the rotary drive 34 is arranged, with the aid of which the rocker 36 can be rotated. On its other end, the rocker 36 has a pivot drive 37 with a pivot drive motor 371. The pivot drive motor 371 can be formed as an electric servomotor or as a stepper motor.

(32) In the area of its end, the rocker 36 has a bracket 38 in order to detachably hold a carrier rail 21 or 22. The bracket 38 has a detachable mechanical holder, not shown, and an electrical plug connection. With the aid of the mechanical holder, a carrier rail 21 or 22 can be detachably secured to the bracket 38, for example screwed. Via the electrical plug connection, electrical power supply lines as well as control lines can be guided from the rocker to the carrier rail. Via the power supply lines, a power supply of the drive mechanisms 241 of the transport carriages 24 is ensured. Via control lines, the transport carriages 24 or the drive mechanisms 241 thereof can be selectively actuated. For this purpose, each drive mechanism 241 has an individual address, via which an electric linear motor 242 of the drive mechanism 241 can be selectively actuated. Both the speed and the drive direction of an individual drive mechanism 241 can be controlled in a targeted manner.

(33) In FIGS. 4a and 4b, the transport device 2 is shown with an alternative design of the rocker 26 as parallel guide. The rocker 36 is formed in two parts, preferably as a parallelogram guide rod. This means, the rocker 36 has a first rocker arm 361 and a second rocker arm 362. The two rocker arms 361 and 362 are not directly connected to each other. One end of both rocker arms 361 and 362 is each rotatably mounted on the lifting carriage 3 via a pivot bearing 351 or 352, respectively. The first pivot bearing 351 has a rotary drive 34, in order to rotate the rocker 36 relative to the lifting carriage 3.

(34) The rocker 36 has a bracket 38 at its end facing the carrier rail. The end of each rocker arm 361 and 362 is secured to the bracket 38 and mounted there rotatably. In this design of the rocker 36 consisting of two rocker arms 361 and 362, a pivot drive between bracket and carrier rail can be omitted. Because of the parallelogram linkage of the bracket 38 via the two rockers 361 and 362 which are offset with respect to each other in the vertical direction, it is automatically achieved, on rotating the rocker 36, that the bracket 38 remains in a horizontal alignment with the carrier rail. This emerges from the representation of FIGS. 4a and 4b, in which two different positions of the carrier rail 21 are represented. FIG. 4b shows the carrier rail in the maximum deflection in the clamping direction. In FIG. 4a, the carrier rail is arranged at the same vertical height but in the opened position, i.e. moved contrary to the clamping direction.

(35) In the representations of FIGS. 6a and 6b, a further representation of the transport device is represented with a divided rocker 36. FIG. 6a shows the rocker 36 with a first rocker arm 361 and a second rocker arm 362, wherein the driven rocker arm 361 is arranged below the non-driven rocker arm 362 in the vertical direction. In the representation of FIG. 6b in contrast, the only difference is that the rocker 36 is formed in such a way that the non-driven second rocker arm 362 is arranged below the driven rocker arm 361 in the vertical direction.

(36) The representation of FIG. 6a shows a variant of the actuation, in which the lifting carriage 3 is arranged below the carrier rails. The representation 6b shows a variant of the actuation, in which the lifting carriage 3 is arranged above the carrier rails. By utilizing the entire length of the lift rail 32, the position of the lifting carriage can thus be adapted to the respective space requirement. If the lower gate area is required for the workpiece transport, the position of the lifting carriage represented in FIG. 6b is used for the actuation. If, in contrast, the upper area of the press gate is required for the workpiece transport, the position of the lifting carriage 3 represented in FIG. 6a is used for the actuation.

(37) In FIG. 5 the movement range of the rotary drive 34 is represented by way of example. The one-part rocker 36 can be pivoted through 360° via the rotary motor 341. Thereby, the carrier rail 21 or 22 respectively can be pivoted out of the pressing area through the gate area T. Outside the pressing area, adjustments or repair work can then be carried out on the carrier rails 21 or 22 and/or the transport carriages 24 and/or the workpiece grippers 25. Outside the pressing area means, at the same time, outside the danger area of the press. After carrying out the assembly work or adjustments, the carrier rail 21 or 22 respectively can then be moved back into the pressing area again via the rotary drive 24. In this way, the utilization of the installation space of the press line is optimized. No additional installation space needs to be provided within the pressing area in order to change tools. At the same time, it is not necessary for a technician to work inside the pressing area, i.e. inside the danger area of the press die, during maintenance work. Through the transport device according to the invention, a press line can thus be created which is constructed as compactly as possible and with which, at the same time, the safety during maintenance of the line is increased.

LIST OF REFERENCE NUMBERS

(38) 1 Press line 11 Press bed 12 Press base 13a Press upright 13b Press upright 13c Press upright 13d Press upright T1, T2 Gate area F1, F2 Press window W Workpiece transport direction 2 Transport device 21 First carrier rail 22 Second carrier rail 24 Transport carriage 241 Drive mechanism 242 Electric linear motor 25 Workpiece gripper 3 Lifting carriage 31 Lift drive 32 Lift rail 33 Lifting motor 34 Rotary drive 341 Rotary motor 351 First pivot bearing 352 Second pivot bearing 36 Rocker 361 First rocker arm 362 Second rocker arm 37 Pivot drive 371 Pivot motor 38 Bracket 39 Longitudinal drive 391 Longitudinal drive motor 392 Toothed strip 393 Electric linear motor