PROCESS AND SYSTEM FOR PRESSURE FORMING OF A WORKPIECE
20190329311 · 2019-10-31
Assignee
Inventors
- Sture Olsson (Västerås, SE)
- Mikael Bergkvist (Västerås, SE)
- Carolina Nilsson (Västerås, SE)
- Bjorn Carlsson (Västerås, SE)
- Hans Hedstrom (Västerås, SE)
Cpc classification
B21D22/10
PERFORMING OPERATIONS; TRANSPORTING
B30B5/02
PERFORMING OPERATIONS; TRANSPORTING
B30B15/34
PERFORMING OPERATIONS; TRANSPORTING
International classification
B21D22/10
PERFORMING OPERATIONS; TRANSPORTING
B30B5/02
PERFORMING OPERATIONS; TRANSPORTING
B30B15/02
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A process and a system for forming of a workpiece using a press including a pressure generator, a forming tool, and an at least in part elastically deformable element, are disclosed. At least one of the workpiece or the forming tool is heated, and the workpiece is formed using the press so as to obtain a formed workpiece. The heating of at least one of the workpiece or the forming tool is such that the temperature of the at least one of the workpiece or the forming tool during the forming of the workpiece by way of forming pressure generated by the pressure generator is higher than the ambient temperature.
Claims
1-24. (canceled)
25. A process for forming of a workpiece using a press comprising a pressure generator, a forming tool, and an at least in part elastically deformable element, wherein, during forming of the workpiece, the workpiece is arranged adjacent to the forming tool and the elastically deformable element and between one side of the elastically deformable element and a forming surface of the forming tool so that one side of the workpiece faces the elastically deformable element and another side of the workpiece faces the forming tool, and wherein the pressure generator is configured to exert a forming pressure of at least 5 MPa on the elastically deformable element and/or the forming tool so as to pressurize at least one of one side of the elastically deformable element opposite to the side of the elastically deformable element facing the workpiece, or a surface of the forming tool opposite to the forming surface, thereby causing the elastically deformable element to deform so as to cause the side of the workpiece facing the forming tool and the forming surface to be pressed against each other such that the workpiece is formed at least in part in accordance with the shape of the forming surface, the process comprising: heating at least one of the workpiece or the forming tool; and forming the workpiece using the press so as to obtain a formed workpiece; wherein the heating of at least one of the workpiece or the forming tool is such that the temperature of the at least one of the workpiece or the forming tool during the forming of the workpiece by way of the forming pressure is higher than the ambient temperature; the process further comprising: arranging the forming tool and the workpiece in a container comprising at least one opening, such that when the forming tool and the workpiece are arranged in the container, one side of the workpiece faces the forming tool and another side of the workpiece is directed towards the at least one opening; heating the workpiece and the forming tool when they are in the container; arranging the container in the press such that the other side of the workpiece, which is directed towards the at least one opening, is facing the elastically deformable element, wherein the forming of the workpiece using the press is carried out while the forming tool and the workpiece are in the container; and removing the container from the press with the forming tool and the formed workpiece still being in the container and with the at least in part elastically deformable element still being in the press.
26. A process according to claim 25, wherein the pressure generator is configured to exert a forming pressure in a pressure range of 5 MPa to 200 MPa on at least one of the elastically deformable element and the forming tool.
27. A process according to claim 25, wherein the at least one of the workpiece or the forming tool is heated such that the temperature of the at least one of the workpiece or the forming tool during forming of the workpiece is between 200 C. and 500 C.
28. A process according to claim 25, wherein the at least one of the workpiece or the forming tool is heated such that the temperature of the at least one of the workpiece or the forming tool during forming of the workpiece is between 250 C. and 350 C.
29. A process according to claim 25, further comprising: arranging a thermally insulating element between the workpiece and the elastically deformable element such that the thermally insulating element is arranged adjacent to the workpiece and the elastically deformable element, respectively, so as to thermally insulate the elastically deformable element from the workpiece during the forming of the workpiece.
30. A process according to claim 25, further comprising: arranging the thermally insulating element relatively to the container such that the thermally insulating element at least in part closes the at least one opening of the container.
31. A process according to claim 25, wherein the heating of the at least one of the workpiece or the forming tool is carried out using induction heating.
32. A process according to claim 25, wherein the heating of the at least one of the workpiece or the forming tool is carried out in a heating device separately arranged with respect to the press.
33. A process according to claim 25, further comprising actively cooling the formed workpiece.
34. A process according to claim 25, further comprising at least one of trimming or shaving or sensing at least one dimension of the formed workpiece.
35. A process according to claim 25, wherein the arranging of the container in the press such that the other side of the workpiece, which is directed towards the at least one opening, is facing the elastically deformable element, is such that the elastically deformable element is between the at least one opening and the forming tool and the workpiece during the forming of the workpiece.
36. A process according to claim 25, wherein the arranging of the forming tool and the workpiece in a container comprising at least one opening and a bottom and side walls terminating in a peripheral rim surrounding the opening, such that when the forming tool and the workpiece are arranged in the container, one side of the workpiece faces the forming tool and another side of the workpiece is directed towards the at least one opening, is such that the side of the workpiece facing the forming tool and the side of the workpiece directed towards the at least one opening are opposite sides of the workpiece.
37. A process according to claim 25, wherein the pressure generator is configured to exert a forming pressure in a pressure range of 50 MPa to 200 MPa on at least one of the elastically deformable element and the forming tool, and the at least one of the workpiece or the forming tool is heated such that the temperature of the at least one of the workpiece or the forming tool during forming of the workpiece is between 250 C. and 350 C.
38. A system for forming of a workpiece, the system comprising: a press comprising a pressure generator, a forming tool, and an at least in part elastically deformable element, wherein, during forming of the workpiece, the workpiece is arranged adjacent to the forming tool and the elastically deformable element and between one side of the elastically deformable element and a forming surface of the forming tool so that one side of the workpiece faces the elastically deformable element and another side of the workpiece faces the forming tool, and wherein the pressure generator is configured to exert a forming pressure of at least 5 MPa on the elastically deformable element and/or the forming tool so as to pressurize at least one of one side of the elastically deformable element opposite to the side of the elastically deformable element facing the workpiece, or a surface of the forming tool opposite to the forming surface, thereby causing the elastically deformable element to deform so as to cause the side of the workpiece facing the forming tool and the forming surface to be pressed against each other such that the workpiece is formed at least in part in accordance with the shape of the forming surface, so as to obtain a formed workpiece; a heating device configured to heat at least one of the workpiece or the forming tool such that the temperature of the at least one of the workpiece or the forming tool during the forming of the workpiece by way of the forming pressure is higher than the ambient temperature; and a container comprising at least one opening, the container being arranged to accommodate the forming tool and the workpiece such that when the forming tool and the workpiece are arranged in the container, one side of the workpiece faces the forming tool and another side of the workpiece is directed towards the at least one opening; wherein the heating device is configured to heat the workpiece and the forming tool when they are in the container; wherein the container can be arranged in the press such that the other side of the workpiece, which is directed towards the at least one opening, is facing the elastically deformable element, wherein the forming of the workpiece using the press is carried out while the forming tool and the workpiece are in the container; wherein the container can be removed from the press with the forming tool and the formed workpiece still being in the container and with the at least in part elastically deformable element still being in the press.
39. A system according to claim 38, wherein the elastically deformable element is constituted by or includes at least one of natural and synthetic rubber.
40. A system according to claim 38, further comprising: a thermally insulating element arranged between the workpiece and the elastically deformable element such that the thermally insulating element is arranged adjacent to the workpiece and the elastically deformable element, respectively, so as to thermally insulate the elastically deformable element from the workpiece during forming of the workpiece.
41. A system according to claim 40, wherein the thermally insulating element can be arranged relatively to the container such that the thermally insulating element at least in part closes the at least one opening of the container.
42. A system according to claim 40, wherein at least a portion of the container is thermally insulated.
43. A system according to claim 38, wherein the forming tool is removably arranged in the press.
44. A system according to claim 38, wherein the heating device is separately arranged with respect to the press.
45. A system according to claim 38, wherein the heating device comprises an induction heating device.
46. A system according to claim 38, wherein the elastically deformable element comprises a resilient membrane or diaphragm, wherein the pressure generator is configured to controllably exert the forming pressure on the elastically deformable element by way of controllably supplying a pressure medium to a pressure cell in which the elastically deformable element is arranged, whereby the pressure medium pressurizes the one side of the elastically deformable element.
47. A system according to claim 38, wherein the elastically deformable element comprises a pad or cushion, wherein the pressure generator is configured to controllably exert the forming pressure on the elastically deformable element by controllably pressing the elastically deformable element against the workpiece.
48. A system according to claim 38, wherein the workpiece comprises at least one of: a blank, a plate, or sheet metal.
49. A system according to claim 38, wherein the workpiece comprises a material selected from at least one of: at least one composite, aluminium or titanium or any alloy thereof, steel, nickel, or an alloy including nickel.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] Exemplifying embodiments of the present invention will be described below with reference to the accompanying drawings.
[0041]
[0042]
[0043]
[0044] All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate embodiments of the present invention, wherein other parts may be omitted or merely suggested.
DETAILED DESCRIPTION
[0045] The present invention will now be described hereinafter with reference to the accompanying drawings, in which exemplifying embodiments of the present invention are shown. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments of the present invention set forth herein; rather, these embodiments are provided by way of example so that this disclosure will convey the scope of the present invention to those skilled in the art.
[0046]
[0047] The process 100 comprises steps 110, 120, 130, 140 and 150 which will be described in the following. The arrows in
[0048] At 110, a workpiece 10 is provided, which workpiece 10 is to be formed by way of the process 100. The workpiece 10 may for example comprise at least one of a blank, a plate, or sheet metal, but is not limited thereto. The workpiece 10 may for example comprise a material selected from at least one of: at least one composite, aluminium or titanium or any alloy thereof, steel, nickel, or an alloy including nickel, but is not limited thereto.
[0049] In accordance with the illustrated embodiment of the present invention, a container 30 may be provided. As illustrated in
[0050] At 120, the workpiece 10 and the forming tool 22 are heated. In accordance with the illustrated embodiment of the present invention, both the workpiece 10 and the forming tool 22 are heated. It is however to be understood that heating of both the workpiece 10 and the forming tool 22 may not be required, and it may be sufficient to heat only one of them (either the workpiece 10 or the forming tool 22). As per the embodiment of the present invention illustrated in
[0051] As illustrated in
[0052] As illustrated in
[0053] As illustrated in
[0054] At 130, the heated workpiece 10 and the forming tool 22 are brought to the press 20 for forming of the workpiece 10 using the press 20 so as to obtain a formed workpiece 60. As illustrated in
[0055] The heating of the workpiece 10 and/or forming tool 22 may be carried out some period of time prior to the actual forming of the workpiece 10 by the press 20 takes place. Before the actual forming of the workpiece 10 is taking place, the workpiece 10 and/or the forming tool 22 may therefore cool to some extent, e.g., by means of convection during transportation or conveyance of the workpiece 10 and/or forming tool 22 to the press 20. However, by way of heating the workpiece 10 and/or forming tool 22 while taking into account such cooling and the time required to transport the workpiece 10 to the press 20 and begin the forming of the workpiece 10, the workpiece 10 and/or the forming tool 22 can have the desired temperature during the forming of the workpiece 10 in the press 20. In other words, the heating of the workpiece 10 and/or forming tool 22 may overshoot to some extent. That is, immediately after the heating of the workpiece 10 and/or forming tool 22 has been carried out, the temperature of the workpiece 10 and/or forming tool 22 may be higher than the desired temperature of the workpiece 10 and/or forming tool 22 during the actual forming of the workpiece 10 by the press 20. Such overshoot heating may take into account cooling of the workpiece 10 and/or the forming tool 22 that may take place until the actual forming of the workpiece 10 by the press 20 takes place, such that the temperature of the workpiece 10 and/or forming tool 22 during the actual forming of the workpiece 10 by the press 20 is the desired or required temperature.
[0056] As indicated in
[0057] During forming of the workpiece 10 in the press 20, the workpiece 10 is arranged adjacent to the forming tool 22 and the elastically deformable element, and between one side of the elastically deformable element and a forming surface 23 of the forming tool 22 so that one side of the workpiece 10 faces the elastically deformable element and another side of the workpiece 10 faces the forming tool 22.
[0058] As illustrated in
[0059] According to the illustrated embodiment of the present invention, the pressure generator 21 is configured to (possibly controllably) exert a forming pressure of at least 5 MPa on the elastically deformable element so as to pressurize one side of the elastically deformable element opposite to the side of the elastically deformable element facing the workpiece 10. The pressurization of the side of the elastically deformable element causes the elastically deformable element to deform so as to cause the side of the workpiece 10 facing the forming tool 22 to be pressed against the forming surface 23 such that the workpiece 10 is formed at least in part in accordance with the shape of the forming surface 23. The heating of the workpiece 10 and the forming tool 22 is such that the temperature of the workpiece 10 and the forming tool 22, during the forming of the workpiece 10 by way of the forming pressure, is higher than the ambient temperature. The heating of the workpiece 10 and the forming tool 22 may take into account any cooling of the workpiece 10 and/or the forming tool 22 which may take place during transportation of the workpiece 10 and the forming tool 22 to the press 20 and until the forming of the workpiece 10 can take place.
[0060] The pressure generator 21 could for example comprise a hydraulic ram assembly or at least one hydraulic cylinder, which for example may be mechanically connected or coupled to the elastically deformable element. It is however to be understood that another type or other types of pressure generators may be employed, such as, for example, any suitable pressure generator as known in the art. The elastically deformable element may for example comprise a resilient membrane or diaphragm, a pad, or a cushion such as described in the foregoing. The elastically deformable element may for example be constituted by or include natural and/or synthetic rubber.
[0061] The principle of such flexible forming of the workpiece 10 as described in the foregoing is illustrated in
[0062]
[0063] According to the example illustrated in
[0064] During forming of the workpiece 10 in the press 20, the workpiece 10 (comprising for example a metallic plate or sheet metal) is placed in the press 20 such that the workpiece 10 is arranged adjacent to the forming tool 22 and the elastically deformable element 24, and between one side of the elastically deformable element 24 (the lower side thereof in
[0065] As indicated in
[0066] For the case illustrated in
[0067] Depending on the extent or degree to which the workpiece 10 and/or the forming tool 22 is heated, it may be desired or possibly even required to provide thermal insulation, for example between the elastically deformable element 24 and the workpiece 10. That is to say, in case the workpiece 10 and/or the forming tool 22 are heated to a relatively high temperature for the forming of the workpiece 10, thermal insulation for example between the elastically deformable element 24 and the workpiece 10 may be desired or even required. For example, there may be a limit on how much the elastically deformable element 24 can be heated without being damaged or broken. Whether such thermal insulation should or shall be provided may for example depend on the choice of material(s) which the elastically deformable element 24 is made of, the type of elastically deformable element 24 (e.g., whether a resilient membrane or diaphragm or a pad is employed), or the choice of any possible pressure medium which may be used (in case the press 20 is of pressure cell type). Such thermal insulation can for example be provided by a thermally insulating element 31, e.g. comprising a thermally insulating lid 31, such as described in the foregoing with reference to
[0068] As mentioned in the foregoing, the press 20 could in alternative be constituted by or include a press of pressure cell type, wherein an elastically deformable element in the form of a resilient membrane or diaphragm is utilized for forming the workpiece by way of fluid pressure pressurizing the resilient membrane or diaphragm, such as described in the foregoing. The press 20 could for example be constituted by, or be based on, a press of pressure cell type of the so called Flexformor fluid cell formingtype of presses for sheet metal forming which are produced by the Applicant. Such type of presses are capable of providing a very high controllability in the forming pressure, and may permit forming pressures within a wide pressure range, such as between (about) 80 MPa and (about) 200 MPa or even more.
[0069] Thus, the pressure generator 21 may in alternative or in addition comprise a pressure cell (not shown in
[0070] With further reference to
[0071] At 140, the formed workpiece 60 is cooled. Although the cooling of the formed workpiece 60 is indicated in
[0072] At 150, the formed workpiece 60 may be trimmed and/or shaved, by means of some trimming and/or shaving processing equipment for example such as known in the art. The trimming and/or shaving processing equipment is schematically indicated at 70. As known in the art, shaving of a workpiece is to remove a relatively small amount of material from the edges of the workpiece for example to improve the finish of the edges of the workpiece or to attain a specific shape of the edges of the workpiece. And as further known in the art, trimming of a workpiece is to cut away excess or unwanted irregular features from the workpiece. For example, edges of the (semi-)formed workpiece 60 may be trimmed, if needed. The trimming or shaving at 150 is not required and may be omitted. In alternative or in addition, at least one dimension of the formed workpiece 60 may be measured or sensed at 150. There may for example be provided some appropriate means or a unit as known in the art configured to measure or sense at least one dimension of the formed workpiece 60. The means or a unit, which may be included in the equipment 70, may for example be an optically based means or unit, and may for example include one or more lasers. Based on the measurement or sensing of at least one dimension of the formed workpiece 60, margins of peripheral portions of the formed workpiece 60 may then for example be trimmed and/or shaved such as described in the foregoing, for example in order to improve the finish of the edges of the workpiece or to attain a specific shape or size (e.g., of the edges) of the workpiece. In alternative or in addition, any further forming of the workpiece at 150 that may take place may be carried out by hand, for example using a handheld tool.
[0073] Although not illustrated in
[0074] As indicated in
[0075] In conclusion, a process and a system for forming of a workpiece using a press comprising a pressure generator, a forming tool, and an at least in part elastically deformable element, are disclosed. At least one of the workpiece or the forming tool is heated, and the workpiece is formed using the press so as to obtain a formed workpiece. The heating of at least one of the workpiece or the forming tool is such that the temperature of the at least one of the workpiece or the forming tool during the forming of the workpiece by way of forming pressure generated by the pressure generator is higher than the ambient temperature.
[0076] While the present invention has been illustrated in the appended drawings and the foregoing description, such illustration is to be considered illustrative or exemplifying and not restrictive; the present invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the appended claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.