WO2011006557A1

WO2011006557A1 - Mould and device for producing shaped parts

Info

Publication number: WO2011006557A1
Application number: PCT/EP2010/003344
Authority: WO
Inventors: Dieter Kapp
Original assignee: Theodor Gräbener GmbH & Co. KG
Priority date: 2009-07-16
Filing date: 2010-06-02
Publication date: 2011-01-20
Also published as: PL2277642T3; ES2392010T3; EP2277642B1; EP2277642A1

Abstract

The invention relates to a mould for the simultaneous high-pressure forming of at least two metallic workpieces, comprising an upper mould part (71) with a forming die and a lower mould part (72) with a feed line for exposing a workpiece to fluid under high pressure, wherein at least one intermediate mould part (73) is arranged in a sandwich-like manner between the upper mould part (71) and the lower mould part (72), the side of which intermediate part that is facing the upper mould part (71) has a feed line (736) for exposing a workpiece to fluid under high pressure and the side of which intermediate part that is facing the lower mould part (72) is provided with a forming die. The invention also relates to a device for producing shaped parts, comprising two cross members, which are connected to each other by means of tie bars, wherein a pressing module that receives such a multistage mould (7) is arranged between the cross members (11, 12).

Description

Tool and device for the production of molded parts

The invention relates to a tool for simultaneous high-pressure forming of at least two metallic workpieces according to the preamble of patent claim 1. The invention further relates to a device for producing molded parts according to the preamble of patent claim 7.

For the production of workpieces by a chipless forming process usually presses are used in which forming tools are used to receive a workpiece blank and then bring this by appropriate force into the desired shape. In particular, in the field of forming plate-shaped semi-finished products, such as sheet metal, the process of high pressure forming (English, hydroforming) has established, which is characterized by great design freedom in the design and allows very high degrees of deformation. The semi-finished product is pressed with very high pressure against a mold, whereby the deformation is achieved. This creates large, acting in opposite directions forces that must be absorbed by a stand. The forces arising transversely to the mold division are absorbed by the hydroforming tool. This stand usually consists of two oppositely arranged, substantially rectangular yokes, which are held together by tie rods.

A disadvantage of the aforementioned presses that they are formed due to their design and the required dimensions by the forces occurring during the forming process very space intensive. Furthermore, the production throughput of these presses is limited.

The invention aims to remedy this situation. The invention has for its object to provide a tool and a device for the production of molded parts, which in a compact design an increased production throughput achieved possible. According to the invention, this object is achieved by a tool having the features of patent claim 1.

With the invention, a tool for high pressure forming of metallic workpieces is created, which allows for a compact design an increased production throughput. By providing an intermediate tool part which is sandwiched between the upper die part and the lower die part and which has on its side facing the tool upper part a supply line for pressurizing a workpiece with fluid under high pressure and its lower part facing the tool is provided with a Umformmatrize, which is simultaneous forming of several parallel arranged workpieces allows. It has been shown that the compressive forces applied to the intermediate tool part during the forming process essentially cancel each other out, so that the forces acting on the upper tool part and the lower tool part do not rise proportionally with the forming processes taking place inside the tool, but rather are only insignificantly changed , It follows that the traverses receiving the tool as well as the tie rods connecting them do not have to be dimensioned much larger, despite a significantly increased production throughput.

In a development of the invention, the supply line of the tool lower part is connected to the supply line of the at least one intermediate tool part. This allows a similar pressurization of the workpieces located in the tool. Such a uniform pressurization causes a uniform pressurization of both sides of the at least one intermediate tool part, whereby the applied compressive forces are canceled against each other.

In an embodiment of the invention, the upper tool part and / or the lower tool part has a compensation plate on which the forming die is arranged and which is controlled to be bendable against the process pressure-induced bending direction of the forming die. As a result, a defined bending of the forming matrice opposite the process pressure-indicated bending achievable, whereby the compensation of the process pressure-induced bending is effected.

In a development of the invention, the compensation plate can be acted upon by a hydraulic plate in such a way with fluid pressure that a bending of the compensation plate can be achieved. As a result, a well controllable bending of the compensation plate is possible.

In an embodiment of the invention, the compensation plate is connected in a planar manner to a distance plate, in which a hydraulic line is introduced, which opens into a depression of the compensation plate facing the distance plate. As a result, the formation of a fluid pressure pad is possible, whereby over the surface uniform forming pressure is achieved. The stated object is further achieved by a device having the features of patent claim 7. The term "pressing module" is understood below to mean any device which is suitable for exerting a compressive force in the direction of the oppositely arranged cross-member Preferably, the cross-members have an essentially circular base surface, whereby a uniform introduction of the forming forces into the tie rods is ensured.

Preferably, the tie rods are cylindrical and provided at least one end with a clamping device. As a result, a simple conversion of the device is possible. The upper traverse can be easily removed from the tie rods or attached to this, after which the tie rods are fixed to the tensioner on the crossbar. The tensioning device may be formed, for example, by a threaded portion of the tie rods, on which the tension is made possible by a nut. Any suitable device for releasably tensioning and fixing a tie rod is suitable.

In an embodiment of the invention, at least one traverse on an annular portion which receives a pressing module, wherein at least two support blocks are arranged between which at least one passage is formed and over which the distance between the trusses is adjustable to one another. As a result, the distance between the trusses is optimally adjusted to each other depending on the application field.

Preferably, at least one annular portion of a traverse is formed as a separate support ring, which is positively connected to the traverse.

By providing a separate support ring notch effects are avoided, as they occur when providing a cylindrical recess between the bottom and side walls of such a recess. Upon the occurrence of horizontally acting forces, the support ring can expand outwards, without causing damage to the cross-member positively connected to this support ring. In an advantageous embodiment, the pressing module comprises at least one hydraulic cylinder. As a result, a position of the molded part is made possible to the tool. In addition, a short-stroke cylinder can be mounted on the cylinder piston. Such cylinders enable a defined positioning of the molded part on the tool and ensure that the tool is optimally closed during the forming process.

In an embodiment of the invention, the hydraulic cylinder is formed by an annular portion in which a piston is guided. This allows a compact design while minimizing components. The Traverse provided with an annular section also assumes the function of a cylinder housing.

Preferably, the traverse is provided with at least one cylinder bore for fluid supply of the hydraulic cylinder. The fluid performs two functions: firstly, it allows uniform pressurization of the piston carried in the cylinder; on the other hand it forms a pressure pad between cylinder / Traverse and piston and serves as the decoupling of traverse and piston, whereby a deflection of the piston is counteracted.

Advantageously, at least two return cylinders for guiding the piston of the hydraulic cylinder are arranged. On the one hand, these return cylinders serve to displace the piston of the hydraulic cylinder within the cylinder housing, in particular the return cylinders are used to push the piston back into the starting position. On the other hand, the back-pressure cylinders serve to guide the piston of the hydraulic cylinder and thus prevent tilting and twisting of the piston.

In an embodiment of the invention, two substantially semicircular support blocks are arranged, between which a passage is formed suitable for clocking through a sheet to be formed. As a result, the continuous deformation of existing as a coil sheets is possible.

In an alternative embodiment of the invention, four substantially quarter-circle ring-shaped support blocks are arranged, between which two passages are formed, of which at least one passage is suitable for clocking through a sheet to be formed. By the second implementation, a post-processing of a molded part, for example by means of laser allows. With sufficient width of the second implementation, the possibility of performing semi-finished products from two sides is created, whereby the flexibility of the device is further increased.

In a further embodiment of the invention, the support blocks are formed from a plurality of stacked, preferably plate-like sub-segments. As a result, a stepwise change in the height of the support blocks by adding or removing individual sub-segments is possible. Alternatively, the support blocks can also be segmented vertically. In a further development of the invention, both feedthroughs are suitable for clocking through a workpiece to be formed, and the tool is designed in such a way that a clocking through of less than at least two superimposed, arranged at right angles to each other workpieces is possible. As a result, the continuous deformation of coils present as a coil is made possible by feeders arranged offset from one another, whereby an increased production throughput with minimized space requirements is made possible.

Other developments and refinements of the invention are specified in the remaining subclaims. An embodiment of the invention is illustrated in the drawings and will be described in detail below. Show it:

Figure 1 shows the schematic, spatial representation of an apparatus for the production of moldings;

FIG. 2 shows the illustration of the device from FIG. 1 in section (without tool);

Figure 3 shows the representation of the device according to Figure 2 with additionally arranged Kurzhubzylinder;

FIG. 4 shows the schematic representation of the hydroform stacking tool set of the device from FIG. 1;

Figure 5 is a schematic representation of an apparatus for the production of

Moldings with a passage and multi-part semicircular support blocks in section;

Figure 6 shows the representation of the device of Figure 5 with two feedthroughs and multi-part quarter circle annular support blocks in section and

Figure 7 is a schematic representation of a device according to Figure 6 with a separate support ring and multi-part quarter-circular support blocks. The device chosen as an exemplary embodiment for the production of molded parts is designed for the process of hydroforming and comprises a housing 1, which is formed by two cylinder-like, opposite ordered trusses 11, 12 is formed, which are connected to each other circumferentially tie rods 13. The tie rods 13 are formed as cylindrical rods, which have at both ends - not shown - external thread which receive nuts 131 for clamping the tie rods 13. The tie rods may alternatively have an oval or polygonal cross-section.

The trusses 11, 12 have centrally a circular shoulder 111, 121 for the positive reception of a circumferential support ring 2. The support rings 2 have an outer diameter identical to the crossbars 11, 12 and an inner diameter corresponding to the outer diameter of the shoulders 111, 121.

Within the support rings 2, a piston 4, 5 is arranged in each case, such that in cooperation with in each case one cross member 11, 12 with a arranged support ring 2, a hydraulic cylinder is formed. Traverse 11, 12 and support ring 2 thereby form the cylinder housing in which the piston 4, 5 is slidably guided. In the trusses 11, 12, a cylinder bore 112, 122 is respectively centrally inserted, which serves to supply the hydraulic cylinder thus formed with hydraulic fluid. For this purpose, the cylinder bores 1 12, 122 are each connected to a hydraulic line (not shown).

In an alternative embodiment, only the lower provided with a cylinder bore 121 cross member 12 may be formed with the arranged on this support ring 2 in interaction with the piston 5 as a hydraulic cylinder and the upper cross member, which must have no cylinder bore 112, takes within the support ring 2 a Pressure pad, for example, a rubber pad on which the upper piston 4 is applied. Here, the rubber cushion is the deflection compensation; a pressurization of the upper piston 4 in the direction of the opposite lower piston 5 is not carried out.

Between the pistons 4, 5, four back pressure cylinders 9 are arranged in the embodiment. The return cylinder 9 serve in the direction of the trusses 11, 12th directed return movement of the pistons 4, 5 within the support rings 2. In addition, a tilting of the pistons 4, 5 can be prevented within the support rings 2 on the back pressure cylinder 9. A spacer plate 711, 721 of a hydroforming tool 7 is fastened to the pistons 4, 5 in each case. In order to optimize the setting of a workpiece to be reshaped, an additional short-stroke cylinder 6 can be arranged on the lower piston 5 (cf., FIG. 3), on which in turn the lower spacer plate 721 is mounted. Of course, an arrangement of an additional Kurzhubzylin- on upper piston 4 is possible.

The hydroforming tool 7 consists essentially of an upper tool part 71 and a lower tool part 72, between which two intermediate tool parts 73 are arranged. The upper tool part 71 includes an upper spacer plate 711 to which a compensation plate 712 for deflection compensation is attached. The compensation plate 712 has on its side facing the spacer plate 711 centered on a surface recess 713 which is sealed by a seal 714 against the spacer plate 711 and in which a disposed within the spacer plate hydraulic line 715 opens. On its underside facing away from the spacer plate 711, a tool plate 716 is arranged on the compensation plate, which has the contour to be shaped into the workpiece.

The lower tool part 72 includes a lower spacer plate 721 to which a compensation plate 722 for deflection compensation is attached. In the embodiment according to FIG. 4, the lower spacer plate 721 is identical to the upper spacer plate 711. The compensation plate 722 has on its side facing the spacer plate 721 in the middle a flat recess 723, which is sealed by a seal 724 against the spacer plate 721 and in which a disposed within the spacer plate 721 hydraulic line 725 opens. In the compensation plate 722, a hydraulic line 726 is arranged, which is arranged in a second arrangement on its opposite the recess 723. depression 727 of the compensation plate 722 opens. The second, the upper mold half 71 facing recess 727 is sealed by a seal 728 during the forming process against the resting workpiece to be machined. The sealing can also be purely metallic, that is to say without a seal 728. The depressions 713, 723, 727 are only designed to be very flat and serve for the areal distribution of the fluid supplied via the hydraulic lines 715, 725, 726, whereby a pressure pad is formed ,

The intermediate tool part 73 is essentially formed from a tool plate 733, on which a pressure plate 732 is arranged. The tool plate 733 corresponds to the tool plate 716 of the upper tool part 71; the compensation plate 732 substantially corresponds to the pressure plate 722 of the tool lower part 72, but there is no flat depression on the side facing the tool plate 733.

The lines 726, 736 of the compensation and pressure plates 722, 732 are in the exemplary embodiment via - not shown - flexible fluid lines connected to each other. In the exemplary embodiment, the two intermediate tool parts 73 are mounted so as to be vertically displaceable on guide rods 731, wherein compression spring elements 735 are respectively arranged between the upper tool part 71 and the intermediate tool part 73, between the lower tool part 72 and the intermediate tool part 73 and between the intermediate tool parts 73 , The compression spring elements 735 ensure a gap between the tool plates 716, 733 and the respective compensation or pressure plates 722, 732 which are arranged opposite to each other for inserting the workpieces to be deformed. Furthermore, they are slidably connected to the tool upper part 71 for guiding the tool intermediate parts 73 via laterally arranged drivers 730. In the forming of between the upper mold half 71 and the intermediate tool part 73, between the two intermediate tool parts 73 and the intermediate tool part 73 and the lower mold half 72 introduced Workpieces are the workpieces via the lines 726, 736 applied under high pressure with fluid and pressed against the contour of the tool plates 716, 733. In this case, the compensation and pressure plates 722, 732 are sealed off from the respective workpiece via the seals 728, 738. Possible deflections of the tool plate 716 caused by the applied forming pressure can be compensated by applying a fluid to the compensation plate 712 under pressure via the line 715, thereby causing a deflection in or against the pressure-indicated direction (defined adjustability of the pressure deflection of the tool plate 716). , On the compensation plate 722 of the lower tool part 72, a compensating counterbending is likewise effected via the flat depression 723.

Between the support rings 2, two substantially semi-annular support blocks 3 are arranged in the embodiment of Figure 1, which limit the distance between the two support rings 2 to each other by their height. Through the two semi-annular support blocks 3, a passage 30 for the passage of workpieces to be formed is formed (see Fig. 8). This passage 30 is suitable in the embodiment for clocking through slit strip. By using different support blocks 3, the distance between the support rings 2 can be varied, whereby the effective processing height between the pistons 4, 5 is adjustable.

In the embodiment of Figure 5, the support rings 2 are integrally formed on the trusses 11, 12. However, this embodiment has the disadvantage of the notch effect, whereby the trusses 11, 12 are weakened inside in the transition to the support rings 2.

In the exemplary embodiment according to FIGS. 5 to 7, the support blocks 3 are formed by plate-like subsegments 31 arranged one above the other. By adding or removing individual sub-segments 31, an optimum adjustment of the working height between the pistons 4, 5 is adjustable. In the exemplary embodiment according to FIGS. 6 and 7, four quarter-circle annular support blocks 3 are arranged, which in turn are formed from a plurality of sub-segments 31 stacked one above the other. By arranging four quarter-ring-like support blocks, two passages 30 arranged orthogonally to one another are formed, which enables two-sided clocking. The support blocks may alternatively also be designed such that a wide passage for the passage of workpieces through and a narrow passage, the two opposite openings of the additional processing, for example by means of laser can be used, are formed.

Claims

claims

1. A tool for the simultaneous high-pressure forming of at least two metallic workpieces, comprising an upper tool part with a forming die and a lower tool part with a supply line for loading a workpiece with fluid under high pressure, characterized in that between the upper tool part (71) and the lower tool part (72) at least one intermediate tool part (73) is sandwiched, whose side facing the tool upper part (71) has a feed line (736) for acting on a workpiece

Having fluid under high pressure and the tool lower part (72) facing side is provided with a Umformmatrize.

2. Tool according to claim 1, characterized in that the Zulei- device (725) of the lower tool part with the supply line (736) of the at least one intermediate tool part (73) is connected.

3. Tool according to claim 1 or 2, characterized in that the at least one intermediate tool part (73) between the tool upper part (71) and lower tool part (72) is guided vertically displaceably mounted.

4. Tool according to claim 3, characterized in that between the upper tool part (71) and lower tool part (72) at least two guide rails (731) are arranged, by means of which the at least one

Tool intermediate part (73) is guided vertically, wherein spring elements (733) for spacing the at least one intermediate tool part (73) to vertically adjacent tool parts (71, 72, 73) are arranged in the unloaded state.

5. Tool according to one of the preceding claims, characterized in that the upper tool part (71) and / or the tool Part (72) has a compensation plate (712, 722), on which the forming die is arranged and the controlled against the process pressure indicated bending direction of the forming die is bendable.

6. Tool according to claim 5, characterized in that the compensation plate (712, 722) via a hydraulic line (715, 725) can be acted upon with fluid pressure such that a bending of the compensation plate (712, 722) can be achieved.

7. An apparatus for the production of molded parts, comprising two trusses, which are interconnected by tie rods, characterized in that between the trusses (11, 12) a pressing module is arranged, which receives a multi-stage tool (7) according to one claims 1 to 6 ,

8. The device according to claim 7, characterized in that at least one traverse (11, 12) has an annular portion which receives a pressing module, wherein at least two support blocks (3) are arranged between which at least one passage (30) formed det is and over which the distance between the trusses (11, 12) is adjustable to each other.

9. Apparatus according to claim 7 or 8, characterized in that at least one annular portion of a traverse (11, 12) as a separate support ring (2) is formed, which is positively connected to the crossmember (11, 12).

10. Device according to one of claims 7 to 9, characterized in that the pressing module comprises at least one hydraulic cylinder.

11. The device according to claim 10, characterized in that the hydraulic cylinder is formed by an annular portion in which a piston (4, 5) is guided.

12. Device according to one of claims 7 to 1 1, characterized in that two substantially semicircular formed support blocks (3) are arranged, between which a passage (30) is formed suitable for clocking through a workpiece to be formed.

13. Device according to one of claims 7 to 11, characterized in that four substantially vierkreiskreisringförmig formed support blocks (3) are arranged between which two passages (30) are formed, of which at least one passage (30) suitable for clocking a reshaping Workpiece is.

14. Device according to one of claims 8 to 13, characterized in that the support blocks (3) of a plurality of stacked sub-segments (31) are formed.

15. The apparatus of claim 13 or 14, characterized in that both feedthroughs are suitable for clocking a workpiece to be formed and that the tool is designed such that a clocking of at least two superposed, orthogonally arranged workpieces is possible.