Extrusion press with electro-hydrostatic control system

Abstract

The present invention relates to an extrusion press (10, 20, 30) with a press cylinder (111), the press cylinder (111) being driven with an electro-hydrostatic control system (104) for a power transmission and being connected to a separate drive (120, 400) for rapid traverse, with a container (115), wherein the container (115) is connected to a hydraulic cylinder (117) for a power transmission and to a further separate drive (119, 300) for rapid traverse, with a hydraulic cylinder (101) with a locking device (103) for driving a shearing tool (102), wherein the hydraulic cylinder (101) is connected to the electro-hydrostatic control system (104), and wherein the press cylinder (111) in the power transmission and the hydraulic cylinder (101) for driving a shearing tool (102) are controlled alternately via the common electro-hydrostatic control system (104).

Claims

1. An extrusion press comprising: a press cylinder, wherein the press cylinder is driven by an electro-hydrostatic control system for a first traverse and is connected to a separate first drive for a second traverse; a container, wherein the container is connected to a first hydraulic cylinder for a first traverse and is connected to a separate second drive for a second traverse; a second hydraulic cylinder, wherein the second hydraulic cylinder has a locking device, wherein the second hydraulic cylinder is configured to drive a shearing tool, and wherein the second hydraulic cylinder is connected to the electro-hydrostatic control system; and wherein the common electro-hydrostatic control system is operatively arranged to alternately control the press cylinder in the first traverse and the second hydraulic cylinder.

2. The extrusion press according to claim 1, wherein the separate first drive for the second traverse of the press cylinder is an electromechanical drive system.

3. The extrusion press according to claim 1, wherein the separate second drive for the second traverse of the container is an electromechanical drive system.

4. The extrusion press according to claim 1, wherein at least one of the press cylinder, the first hydraulic cylinder of the container, and the second hydraulic cylinder for driving the shear tool comprises a synchronous cylinder or a differential cylinders.

5. The extrusion press according to claim 1, wherein the electro-hydrostatic control system comprises at least one electro-hydrostatic pump unit.

6. The extrusion press according to claim 5, wherein a low-pressure supply is operatively arranged to provide a pressure to the electro-hydrostatic pump unit ranging from 5 bar to 15 bar.

7. The extrusion press according to claim 6, wherein the low-pressure supply comprises a second pump unit, an oil reservoir and a storage safety block.

8. The extrusion press according to claim 1, further comprising a pressure storage and a hydraulic unit, wherein the hydraulic unit is operatively arranged to provide a pressure in the pressure storage and the pressure storage is connected to the press cylinder via a control block.

9. The extrusion press according to claim 8, wherein the pressure storage is connected to the first hydraulic cylinder of the container via the control block.

10. The extrusion press according to claim 1, wherein the separate second drive for the second traverse of the container comprises an electro-hydrostatic drive system.

11. The extrusion press according to claim 1, wherein the separate first drive for the second traverse of the press cylinder comprises an electro-hydrostatic drive system.

12. The extrusion press according to claim 10, wherein the electro-hydrostatic drive system comprises a third hydraulic cylinder, a second electro-hydrostatic control system and an electro-hydrostatic pump unit.

13. The extrusion press according to claim 12, wherein the third hydraulic cylinder comprises a synchronous cylinder or at least one differential cylinder.

14. The extrusion press according to claim 11, wherein the separate second drive for the second traverse of the container comprises a second electro-hydrostatic drive system and the electro-hydrostatic drive system and the second electro-hydrostatic drive system each comprise hydraulic cylinders that are each controlled by an electro-hydrostatic control system.

15. The extrusion press according to claim 14, wherein each of the electro-hydrostatic control systems comprises at least one electro-hydrostatic pump unit.

16. The extrusion press according to claim 14, wherein at least one of the electro-hydrostatic control systems is connected to the first hydraulic cylinder via a control block and is operatively arranged to alternately execute the first traverse and the second traverse of the container.

17. The extrusion press according to claim 14, wherein at least one of the electro-hydrostatic control systems is operatively arranged to carry out hydraulic auxiliary functions alternately to the second traverse of the press cylinder.

18. A method of using the extrusion press according to claim 1, comprising the following steps: initiating the first traverse of the press cylinder via the electro-hydrostatic control system; initiating the first traverse of the container via the first hydraulic cylinder; initiating the second traverse of the press cylinder via the separate first drive; initiating the second traverse of the container via the separate second drive; driving a shearing tool via the second hydraulic cylinder and the electro-hydrostatic control system; and, using the electro-hydrostatic control system, actuating the first traverse of the press cylinder alternately with actuating the second hydraulic cylinder for driving the shear tool.

19. The method according to claim 18, further comprising the step of: producing, using the extrusion press, an extrusion in the form of a rod, wire, tube, or profile.

Description

(1) Here the following show:

(2) FIG. 1 is a schematic illustration of an extrusion press with an electro-hydrostatic drive system in accordance with a first embodiment;

(3) FIG. 2 is a schematic illustration of an extrusion press with an electro-hydrostatic drive system in accordance with a second embodiment;

(4) FIG. 3 is a schematic illustration of an extrusion press with an electro-hydrostatic drive system according to a third embodiment.

(5) FIG. 1 shows a schematic illustration of an extrusion press 10 with an electro-hydrostatic control system 104 in accordance with a first embodiment. The electro-hydrostatic control system 104 comprises at least one electro-hydrostatic pump unit 105. In particular, the electro-hydrostatic control system 104 comprises electro-hydrostatic pump units corresponding to the number of components of the extrusion press 10, 20, 30 to be supplied.

(6) The electro-hydrostatic control system 104 is supplied via the low pressure supply 121. The low-pressure supply 121 comprises an oil reservoir 108, a storage safety block 109 and a pump unit 110. The low-pressure supply 121 provides the required preload, with a pressure between 5 bar to 15 bar, in particular 10 bar for the electro-hydrostatic pump units 105 driven in the electro-hydrostatic control system, as an internal supply, which advantageously takes place via a low volume flow.

(7) The extrusion press 10 with electro-hydrostatic control system 104 comprises a press cylinder 111. In FIGS. 1, 2 and 3, the press cylinder 111 is shown as a synchronous cylinder. In particular, the press cylinder 111 can also be designed as a differential cylinder with collectively identical areas. The press cylinder 111 is connected via the hydraulic lines 112, 113 to the electro-hydrostatic control system 104 for supplying the power transmission for the pressing. The rapid traverse of the press cylinder 111 is generated by the drive system 120. In particular, the drive system 120 can have an electromechanical drive system which is connected to the piston of the press cylinder 111 via a gear and linkage. During the rapid traverse, the oil in the press cylinder 111 is conveyed via the circuit 114.

(8) The extrusion press 10 with an electro-hydrostatic control system 104 further comprises a container 115. The container 115 is connected to a hydraulic cylinder 117 with a control block 116 for pressing onto the workpiece. In FIGS. 1, 2 and 3, the hydraulic cylinder 117 is shown as a synchronous cylinder. In particular, the hydraulic cylinder 117 can also be designed as a differential cylinder with collectively identical areas. The hydraulic cylinder 117 is supplied with pressure via a hydraulic unit (not shown) for pressing the container 115 against the tool. The rapid traverse of the container 115 is generated by the drive system 119. In particular, the drive system 119 can have an electromechanical drive system. During the rapid traverse, the oil in the hydraulic cylinder 117 is conveyed via the circuit 118.

(9) The extrusion press 10 with an electro-hydrostatic control system 104 further comprises a hydraulic cylinder 101 with a shear tool 102. In FIGS. 1, 2 and 3, the hydraulic cylinder 101 is shown as a synchronous cylinder. In particular, the hydraulic cylinder 101 can also be designed as a combination of differential cylinders with collectively identical areas. The hydraulic cylinder 101 is connected to the electro-hydrostatic control system 104 via the hydraulic lines 106, 107. The electro-hydrostatic control system 104 applies pressure to the cylinder 101 during the cutting process, so that the shearing tool 102 separates a remnant piece from the continuous profile. During the pressing process by the pressing cylinder 111, the hydraulic cylinder 101 with the shearing tool 102 is held in a non-actuated position. This is done by the locking device 103. The locking device 103 thus prevents unwanted lowering of the heavy shearing tool 102, for example due to a loss of pressure. The locking device 103 can be implemented as a blocking valve or as a combination of blocking valves connected in a circuit.

(10) FIG. 2 shows a schematic illustration of an extrusion press 20 with an electro-hydrostatic control system 104 in accordance with a second embodiment. The basic function is the same as explained for FIG. 1. The same reference signs also designate the same elements as in FIG. 1. The embodiment shown in FIG. 2, however, has further components which are advantageous for certain application scenarios. For example, the extruder 20 with the electro-hydrostatic control system 104 comprises an external pressure storage system 200. The external pressure storage system 200 comprises a control block battery and compression 201, a pump unit 202 and a battery medium pressure 203. The pump unit 202 provides a pressure which is stored in the intermediate pressure storage 203. The medium pressure storage 203 can provide a pressure of 200 bar, for example. The medium pressure storage 203 and the pump unit 202 are connected to the battery and compression control block 201 and are controlled via this. The battery and compression control block are connected to the circulation 114 of the press cylinder.

(11) In the case of extrusion presses with shortened cycle times, the compression and decompression function, which briefly require large volume flows, requires a larger hydraulic unit, including the pressure storage, to generate the hydraulic pressure, but this can be much smaller compared to extrusion presses without the electro-hydrostatic control system 104. By means of the external pressure storage system, a given volume flow can be generated briefly, whereby a faster compression than in the embodiment illustrated in FIG. 1 can be realized. The embodiment of the extrusion press 20 illustrated in FIG. 2 represents a variant of the embodiment of the extrusion press 10 illustrated in FIG. 1 in which the production step of compression is carried out more quickly by the additional pressure of the external pressure storage system 200 and thus the production time is shortened. The production step of compression can also take place in the embodiment of the extrusion press 10 shown in FIG. 1. However, this is slower since less volume flow is available for compression.

(12) Furthermore, the external pressure storage system 200 can be connected via a connection A to the hydraulic cylinder 117 via the control block container 116 and the circuit 118. The connection A is made in particular by a hydraulic line. Advantageously, the pressing force contained in the medium pressure storage 203 can be provided via the battery and compression 201 control block, the pressing force necessary for pressing the container 115 onto the pressing tool. The pressing of the container 115 prevents material from escaping from the pressing tool.

(13) Using the medium pressure storage 203 for quick compression advantageously results in the possibility of using the medium pressure storage 203 for pressing the container 115, so that a hydraulic system for driving the hydraulic cylinder 117 of the container 115 is no longer required and thus saved.

(14) FIG. 3 shows a schematic illustration of an extrusion press 30 with an electro-hydrostatic control system 104 in a third embodiment. The basic function is the same as explained for FIG. 1. The same reference signs also designate the same elements as in FIG. 1. However, in contrast to FIG. 1, the embodiment shown in FIG. 3 has the electro-hydrostatic drive systems 300, 400, which replace the electromechanical drive systems 119, 120 of FIG. 1. The electro-hydrostatic drive systems 300, 400 are constructed identically and have a hydraulic cylinder 301, 401. The electro-hydrostatic drive system 300 is connected to the container 115 for the rapid traverse of the container 115, and the electro-hydrostatic drive system 400 is connected to the press cylinder 111 for the rapid traverse of the press cylinder 111. The hydraulic cylinders 301, 401 are shown as synchronous cylinders. In particular, the hydraulic cylinder 101 can also be designed as a combination of differential cylinders with collectively identical areas.

(15) Furthermore, the electro-hydrostatic drive systems 300, 400 include an electro-hydrostatic control system 302, 402. The electro-hydrostatic control system 302 comprises the control block rapid traverse container 115 and can be connected in particular to the control block container 116 via the connection C and D. The electro-hydrostatic control system 402 comprises the control block rapid traverse press cylinder 111 and can be connected via the connection E and F in particular with auxiliary functions or secondary functions. The connections C, D, E and F are made in particular by a hydraulic line. The designation of the connections does not represent any restriction. In particular, the electro-hydrostatic control system 302 can also supply auxiliary functions or secondary functions and the electro-hydrostatic control system 402 can be connected to the container control block 116.

(16) Furthermore, the electro-hydrostatic drive systems 300, 400 include an electro-hydrostatic pump unit 303, 403.

(17) Supplying the rapid traverses of the extrusion press via the electro-hydrostatic drive systems 300, 400 has the advantage that when the rapid traverses are inactive, the functionality of the electro-hydrostatic drive systems 300, 400 can also be used for other functions by hydraulic switching. In the configuration with the electro-hydrostatic drive systems 300, 400, the advantage over the electromechanical drive systems results from the fact that the electromechanical drive systems are spatially fixed and cannot be used to switch over functionalities.

(18) The electro-hydrostatic drive systems 300, 400 are also supplied in particular via the low pressure supply 121 present in the extrusion press 30 for controlling the electro-hydrostatic control system 104 (not shown). In this regard, the low-pressure supply 121 must be designed according to the components to be controlled. By jointly supplying the electro-hydrostatic control system 104 and the electro-hydrostatic drive systems 300, 400 via the low-pressure supply 121, the scope of the hydraulic supply is reduced both in terms of piping requirements and the size of the units and the oil reservoir, as well as in the required oil volume compared to conventional systems.

(19) A further and alternative embodiment to FIG. 3 results from the combination of the cylinders 301 and 117 as a combination of several differential cylinders or a surface combination integrated in a cylinder housing, which in the sum of their surfaces each result in a cylinder of the same surface with surface switching for a rapid traverse and a force function. This cylinder combination or the special cylinder design is driven by a surface switchover to generate the rapid traverse and force movement of the container 115 with the electro-hydrostatic control system 302, 303 and/or 104.

(20) A further and alternative embodiment to FIG. 3 results from the combination of the cylinders 401 and 111 as a combination of several differential cylinders or a surface combination integrated in a cylinder housing, which in the sum of their surfaces each result in a cylinder of the same surface with surface switching for a rapid traverse and a force function. This cylinder combination or the special cylinder design is driven by a surface switchover to generate the rapid traverse and force movement of the press cylinder 111 with the electro-hydrostatic control system 402, 403 and/or 104.

(21) Furthermore, the external pressure storage system 200 used in the second embodiment of the extrusion press 20, for rapid compression, can also be integrated in the third embodiment of the extrusion press 30.

LIST OF REFERENCE SIGNS

(22) 10 extrusion press, main drive system

(23) 20 extrusion press, main drive system

(24) 30 extrusion press, main drive system

(25) 101 Hydraulic cylinder

(26) 102 Shearing tool

(27) 103 Locking device

(28) 104 Electro-hydrostatic control system

(29) 105 Electro-hydrostatic pump unit

(30) 106 Hydraulic line

(31) 107 Hydraulic line

(32) 108 Oil reservoir, storage

(33) 109 Storage security block

(34) 110 Pump unit

(35) 111 Press cylinder

(36) 112 Hydraulic line

(37) 113 Hydraulic line

(38) 114 Circulation of the press cylinder

(39) 115 Container

(40) 116 Control block for hydraulic cylinder container

(41) 117 Hydraulic cylinder container

(42) 118 Circulation of the hydraulic cylinder of the container

(43) 119 Electromechanical drive system

(44) 120 Electromechanical drive system

(45) 121 Low pressure supply, preload for EPUs

(46) 200 External pressure storage system

(47) 201 Control block battery and compression

(48) 202 Pump unit

(49) 203 Battery medium pressure

(50) 300 Electro-hydrostatic drive system container rapid traverse

(51) 301 Hydraulic cylinder container rapid traverse

(52) 302 Control block rapid traverse container

(53) 303 Electro-hydrostatic pump unit

(54) 400 Electro-hydrostatic drive system press cylinder rapid traverse

(55) 401 Hydraulic cylinder press cylinder rapid traverse

(56) 402 Control block rapid traverse press cylinder

(57) 403 Electro-hydrostatic pump unit

(58) A Hydraulic connection

(59) C, D Hydraulic connection

(60) E, F Hydraulic connection