Stamping or riveting tool

Abstract

The disclosure relates to a punching or riveting tool comprising a frame with a movable punch and a die, wherein the punch and die are guided in a guide decoupled from the frame.

Description

Field of invention

[0001] The invention relates to a punching or riveting tool. In particular, the invention relates to a hydraulic punching or riveting tool. The invention further relates to a guide for a die and a punch for such a punching or riveting tool. Background of the invention

[0002] Punching or riveting tools which include a bracket are known.

[0003] For example, the patent application DE 10 2011 111 533 A1 shows a pneumatic / hydraulic pressure generator which can be coupled with a bracket for punching or setting two-part rivets.

[0004] With such a tool, high pressing forces, especially pressing forces of over 10t, can be generated while maintaining a compact design.

[0005] These tools are used particularly for punching holes in body panels. A hydraulic piston is used to move a punch into a die, thus punching out a hole.

[0006] When stamping high-strength sheets, especially multi-layered composite materials, the material hardly flows during the stamping process. Due to the material's hardness, the stamped slugs are essentially broken out.

[0007] The compressive stress increases abruptly at the beginning of the punching process, which is accompanied by correspondingly high forces acting on the bracket.

[0008] Due to the elastic properties of the yoke material (Hooke's Law), the yoke expands during punching, resulting in the punch and die no longer being precisely aligned axially. Consequently, increased wear or even tool destruction can occur, particularly at the edges of the punch and die. Furthermore, the precision of the punching process suffers. Object of the invention

[0009] In contrast, the invention aims to at least reduce the aforementioned disadvantages of the prior art. In particular, it is an objective of the invention to improve the precision of punching and riveting, as well as to prevent damage to the punching or riveting tool. Summary of the invention

[0010] The object of the invention is already achieved by a punching or riveting tool and by a guide designed for a punching or riveting tool according to one of the independent claims.

[0011] Preferred embodiments and further developments of the invention can be found in the subject matter of the dependent claims, the description and the drawings.

[0012] The invention relates to a punching or riveting tool. This comprises a frame with a movable punch and a die.

[0013] The bracket ultimately serves to hold the punch and to form a counter-holder for the die. In particular, the bracket holds the die securely via a counter-holder, while the punch, which is coupled to the opposite arm of the bracket, moves towards the die.

[0014] In particular, a hydraulic cylinder can be arranged on one arm of the bracket, which includes a piston by means of which pressure can be exerted on the ram.

[0015] According to the invention, the punch and die are guided in a guide decoupled from the frame.

[0016] The basic principle of the invention is based on the use of an additional guide for the axial guidance of the die and punch, on which no pressing force is exerted during a punching or riveting operation. Therefore, during a punching or riveting operation, only the bracket expands, but not the guide.

[0017] Due to the independent guidance, the coaxial alignment of the punch and die is not affected by the applied pressing force. Even if the yoke expands, the die and punch remain axially aligned with each other.

[0018] The guide is preferably inserted into the bracket.

[0019] Preferably, the guide comprises the punch and the die and is inserted into the bracket via a floating bearing.

[0020] The bracket includes, in particular, a pressure piece by means of which the punch can be moved, and a counter-holder. The pressure piece and counter-holder are each coupled to the punch and die, respectively, via a floating bearing.

[0021] In the case of a floating bearing, this can particularly involve a pin that engages in a recess, with play between the recess and the pin. This allows the pin to move within the recess in such a way that it can follow a widening of the bracket.

[0022] The bottom of the recess and the end face of the pin can be flat, conical or dome-shaped.

[0023] According to one embodiment of the invention, the guide is designed as a second bracket, namely as a guide bracket, which is inserted into the bracket.

[0024] Preferably, one arm of the guide bracket comprises a punch guide in which the punch is slidably arranged. To reset the punch after completion of the punching or riveting process, the punch guide can include a spring, in particular a compression spring.

[0025] In a further development of the invention, the guide bracket is divided into two parts and comprises two halves that are slidable relative to each other. The distance between the arms of the guide bracket is thus adjustable. This allows the guide bracket to be easily installed in the bracket or enables adaptation to different bracket sizes.

[0026] The two halves are connected to each other, in particular via a sliding fit. For example, the two halves can be connected to each other via dowel pins that engage in corresponding locating bores.

[0027] Preferably, the die and / or punch is pivotably and / or floatingly mounted relative to a piston or a counter-holder connected to the bracket.

[0028] For example, a pressure piece connected to the piston can engage the punch or a component coupled to the punch via a clearance fit or a cone. Similarly, the die can also be coupled to the arm of the yoke via a clearance fit or a cone.

[0029] On both the punch side and the die side, the arms of the bracket, including the pressure piece or counter-holder, can thus widen relative to each other without changing the axial alignment of the die and punch.

[0030] The punching or riveting tool is preferably designed as a hydraulic tool.

[0031] In a further development of the invention, a counter-support against which the die is supported is axially displaceable. In particular, the die can be axially displaceable by means of an eccentric. This allows for simpler installation of the guide bracket along with the die guide and die. To insert the guide bracket, the counter-support can be retracted and then clamped again by flipping the eccentric.

[0032] Securing the punch and die, especially the punch and die guide, can be done, for example, by means of a pin inserted laterally.

[0033] The invention further relates to a guide, in particular designed as a guide bracket, which is designed for the punching or riveting tool described above.

[0034] The management can include, in particular, all the characteristics described above in connection with management.

[0035] In particular, the guide can include a punch guide in which the punch is arranged to be axially displaceable.

[0036] The die guide may include a spring that resets the die.

[0037] Furthermore, the guide can include a die guide into which the die is inserted. The punch guide and die guide are preferably designed as sleeves, each inserted into an arm of the guide bracket. This improves the precision of the axial alignment relative to each other. Brief description of the drawings

[0038] The subject matter of the invention will below be described with reference to the drawings. Fig. 1 - Fig. 9 This will be explained in more detail using an example. Fig. 1 is a perspective view of a stamping tool according to the invention. Fig. 2 is an exploded view. Fig. 3shows in a perspective view the guide including the stamp, die and corresponding holders. Fig. 4 is a perspective view of the stamp, die and guides in an exploded view. Fig. 5 This is a perspective view of the stamp, die, and guides. Fig. 6 This is a detailed representation of the printing piece and an intermediate piece that is coupled to the die. Fig. 7 This is a perspective view of the intermediate piece. Fig. 8 This is a perspective view of the printed piece. Fig. 9 shows a perspective view of the counterholder and matrix. Detailed description of the drawings

[0039] Fig. 1 Figure 1 shows a perspective view of a stamping tool 1 according to the invention. The stamping tool 1 comprises a bracket 100 with the arm 101 and the arm 102.

[0040] The bracket 100 can include a boom 103, by means of which the bracket 103 can be suspended from a handling device (not shown).

[0041] A hydraulic cylinder 10 is inserted into the arm 101, which can be fixed via the handle 14.

[0042] The hydraulic cylinder 10 includes the hydraulic connection 12. This can be, for example, a coupling with a self-closing hydraulic valve.

[0043] The hydraulic connection 12 allows the punching tool 1 to be supplied with pressure. This can be achieved either by using a portable pressure generator (not shown), which is connected directly to the hydraulic connection 12, or by using a stationary unit (not shown) connected to the hydraulic tool 12 via a hose.

[0044] The hydraulic cylinder 10 serves to axially move the punch, which sits in the punch guide 11.

[0045] A counter-holder 20 is arranged on arm 102, against which the die guide 22 is supported.

[0046] A guide bracket 200, comprising two halves 201 and 202 that can slide relative to each other, is inserted into the bracket 100. The punch guide 11 is secured by the laterally inserted pin 13. Similarly, the die guide 22 is secured by a laterally inserted pin 23. To insert the guide bracket 200, the counter support 20 can be retracted via an eccentric 21.

[0047] After insertion, the counterholder 20 is tightened again by means of the eccentric 21 and the guide bracket 200 is thus connected to the bracket 100.

[0048] During stamping, the resulting pressing forces acting between the punch and die are absorbed by the bracket 100. This causes the opposing arms 101, 102 to widen.

[0049] The guide bracket 200 serves solely for the axial guidance of the punch guide 11 and the die guide 22.

[0050] Therefore, widening the arms 101, 102 relative to each other does not lead to any change in the axial position of punch guide 11 and die guide 22, and thus of punch and die.

[0051] Fig. 2 This is an exploded view of the stamping tool 1. The punch 15, which sits in the punch guide 11, and the die 24, which sits in the die guide 22, can now be seen.

[0052] In the perspective representation according to Fig. 3 The bar is hidden.

[0053] The guide bracket 200 comprises the two halves 201 and 202, which are movable relative to each other. For this purpose, dowel pins 203 are provided at the base of the guide bracket 200, which engage in corresponding dowel bushings of the respective halves 201 and 202.

[0054] The distance between the arms of the guide bracket 200 can be changed in this way.

[0055] The arms or halves 201, 202 of the guide bracket 200 encompass at their ends the two half-shells 204 and 205, which facilitate assembly.

[0056] A hydraulic piston is coupled to a pressure piece 16 via the hydraulic cylinder 10, which moves the punch 15, guided in the punch guide 11, forward to perform a punching operation. During a punching operation, the punch 15 plunges into the die 24, which is located in the die guide 22, which is inserted into half 202 of the guide bracket 200.

[0057] The resulting forces are transferred via a counterholder 26 to the arm of the bracket (102 in Fig. 1 ) forwarded.

[0058] The counterholder 2 can be tightened against the preload of the spring 25 when the guide bracket 200 is inserted.

[0059] In the perspective representation according to Fig. 4 The guide bracket is now also hidden. An intermediate piece 18 is pushed forward via the pressure piece 16, which drives the punch 15 inserted into the punch guide 11.

[0060] In this embodiment, the pressure piece 16 is axially guided by a plastic ring 17 made of elastic material. A clearance fit exists between the pressure piece 16 and the intermediate piece 18, designed such that a change in the axial position of the pressure piece 16 does not affect the axial alignment of the intermediate piece 18 and thus of the plunger 15. The pressure piece 16 and the intermediate piece 18 are therefore coupled via a floating bearing.

[0061] The counterholder 20 is also mounted in a floating manner with respect to the die 24 inserted into the die guide 22.

[0062] In the perspective view according to Fig. 5 The die guide and die guide are now also hidden.

[0063] As already explained above, the pressure piece 16 is mounted floating relative to the intermediate piece 18.

[0064] The stamp 15 is located in a stamp receptacle 19.

[0065] After a punching operation has been carried out, the punch holder 19, together with the punch 15, is reset by the spring 30. The spring 30 is located in the housing of the punch guide.

[0066] The die receptacle 19 is designed as a sleeve that can be displaced within the die guide housing against the compressive force of the spring 30. This sleeve can be secured with a dowel pin 19a.

[0067] The punch receptacle 19 can be designed as a threaded sleeve into which the punch 15 is screwed.

[0068] On the opposite side is the die 24, which is mounted floating in the counterholder 26.

[0069] Details of the floating mounting of the punch and die will be described below with reference to Fig. 6 - Fig. 9 will be explained in more detail.

[0070] Fig. 6 This is a detailed representation of printed piece 16 and intermediate piece 18.

[0071] The pressure piece 16 engages in a recess 18a of the intermediate piece 18.

[0072] This is a game fit.

[0073] As in Fig. 7 As shown, the recess can have conical walls. A dome-shaped design is also conceivable (not shown).

[0074] In this embodiment, the bottom of the recess 18a is flat.

[0075] The in Fig. 8 The depicted pressure piece 16 can, for example, be conical or dome-shaped. This allows for compensation of any tilting or misalignment of the central axes of pressure piece 16 and intermediate piece 18.

[0076] In this embodiment, the end face 16a of the pressure piece 16 is flat. The side walls can be conical.

[0077] The axial position of the intermediate piece 18 is determined solely by the guide bracket.

[0078] A corresponding decoupling is, as in Fig. 9The counterholder 26 is also present on the side of the die 24. It engages in a floating manner in a recess 24a on the back of the die 24.

[0079] The head of the counterholder 26 or the recess on the back of the die 24 can, as shown here, also include a conical wall or be dome-shaped.

[0080] The invention made it possible to ensure precise guidance of the punch and die in a simple way, even when stamping in high-strength materials.

Claims

1. Punching or riveting tool comprising a bracket with a movable punch and a die, characterized in that The punch and die are guided in a guide that is decoupled from the bracket.

2. Punching or riveting tool according to the preceding claim, characterized in that the guide is designed as a guide bracket.

3. Punching or riveting tool according to the preceding claim, characterized in that the guide bracket is divided into two parts and comprises two halves that can be moved against each other.

4. Punching or riveting tool according to the preceding claim, characterized in that the halves are connected by a sliding seat.

5. Punching or riveting tool according to one of the preceding claims, characterized in that the die and / or the punch is pivotably and / or floatingly mounted relative to a piston or a counter-holder which is connected to the bracket, in particular by means of a clearance fit which comprises a recess and a component engaging in the recess.

6. Punching or riveting tool according to one of the preceding claims, characterized in that the punching or riveting tool is designed as a hydraulic tool.

7. Punching or riveting tool according to one of the preceding claims, characterized in that the die is designed to be axially displaceable.

8. Punching or riveting tool according to the preceding claim, characterized in that a counterholder for the die can be moved axially by means of an eccentric.

9. Punching or riveting tool according to one of the preceding claims, characterized in that the guide can be coupled to a punch and / or die guide, in particular by means of a pin that can be inserted laterally.

10. Punching or riveting tool according to one of the preceding claims, characterized in that the punch is arranged axially displaceably in the guide.

11. Punching or riveting tool according to the preceding claim, characterized in thatthe stamp is arranged in the guide in a way that it can be reset by means of a spring.

12. Guide, in particular guide bracket, designed for a punching or riveting tool according to one of the preceding claims.

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