Rivet type contact forming die

Abstract

The utility model provides a rivet type contact forming die, which comprises a bottom die, a first die and a second die, the bottom die is provided with a planar forming surface used for placing a contact material, the forming surface is provided with at least one groove, and the first die is matched with the forming surface so as to perform pre-upsetting welding on the contact material on the forming surface; the second die comprises a second die body, a final pier groove matched with the forming face to conduct final pier forming on the contact material on the forming face is formed in the second die body, and a final pier bottom die needle in sliding fit with the final pier groove is arranged in the final pier groove. And a final pier spring for enabling the final pier bottom die needle to slide towards the opening of the final pier groove is arranged between the secondary die body and the final pier bottom die needle. The forming device is simple in structure, high in production efficiency and good in forming quality, and solves the problem that the rivet type electrical contact of a cake-shaped structure is difficult to form.

Description

Technical Field

[0001] The utility model relates to the technical field of rivet contact preparation, in particular to a rivet type contact forming die. Background Art

[0002] The existing rivet-type electrical contacts are used in the switch electrical contact system, which is an important factor affecting the working reliability of the switch electrical contact system. The rivet-type electrical contact includes a substrate part and an alloy layer arranged on the end surface of the substrate part. The substrate part is generally made of copper, and the alloy layer is mainly made of silver alloy. The substrate part generally adopts a T-shaped structure. In order to facilitate demolding, the demolding angle θ of the contact is between 7 and 25°. The larger the angle, the easier it is to demold.

[0003] However, in some special occasions, the contact is required to be a pancake-shaped structure, without a draft angle, or with a very small draft angle θ < 3°. For this type of special structure rivet contact, it is difficult to produce because it does not have the nail feet of the T-shaped contact and has no draft angle or a very small draft angle. Summary of the invention

[0004] The technical problem to be solved by the utility model is to provide a rivet type contact forming die to solve the problem that it is difficult to form a rivet type electrical contact with a pancake structure.

[0005] The utility model solves the technical problem by adopting a technical solution: a rivet-type contact forming die, comprising a bottom die, a first die and a second die, the bottom die is provided with a flat forming surface for placing contact material, the forming surface is provided with at least one groove, the first die cooperates with the forming surface to perform pre-piercing welding on the contact material on the forming surface;

[0006] The second die includes a second die body, the second die body is provided with a terminal pier groove which cooperates with a forming surface to perform terminal pier forming on the contact material on the forming surface, the terminal pier groove is provided with a terminal pier bottom die pin which slides with the terminal pier groove, and a terminal pier spring is provided between the second die body and the terminal pier bottom die pin to make the terminal pier bottom die pin slide toward the opening of the terminal pier groove.

[0007] Furthermore, a die head is embedded in the second-pass die body, and the terminal pier groove is arranged in the die head.

[0008] Furthermore, the die head material is tungsten steel.

[0009] Furthermore, the grooves are multiple and arranged in a ring shape on the forming surface.

[0010] Furthermore, the groove is circular, the diameter of the groove is 0.03-0.08 mm, and the depth is between 0.3-0.5 mm.

[0011] Furthermore, the first mold includes a first mold body, a primary pier groove is provided in the first mold body, a primary pier bottom mold pin slidably matched with the primary pier groove is provided in the primary pier groove, and a primary pier spring is provided between the primary pier bottom mold pin and the first mold body to make the primary pier bottom mold needle slide toward the opening of the primary pier groove.

[0012] Furthermore, the material of the terminal bottom mold pin is stainless steel.

[0013] The beneficial effects of the utility model are as follows: the rivet-type contact forming die of the utility model is provided with a groove on the bottom die, so that part of the material of the base material part can enter the groove during the first die pressing welding process, thereby fixing the contact material and preventing it from shifting, which is convenient for subsequent processing; and a terminal pier bottom die pin is provided in the terminal pier groove of the second die, and the terminal pier bottom die pin is slidably arranged in the terminal pier groove through the terminal pier spring, and the contact can be pressed and demolded by the terminal pier bottom die pin, which solves the problem of difficulty in demolding due to a small demolding angle or no demolding angle. The rivet-type contact forming die solves the problem of difficulty in forming a pancake-shaped rivet-type electrical contact, and has a simple structure, high production efficiency and good forming quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0015] Figure 1 It is a structural schematic diagram of the utility model;

[0016] Figure 2 It is a top view of the bottom mold of the utility model;

[0017] Figure 3 This is a schematic diagram of a mold structure of the utility model;

[0018] Figure 4 It is a schematic diagram of the two-way mold structure of the utility model;

[0019] As shown in the figure: bottom die 1, first die 2, second die 3, movable die seat 4, contact material 5, forming surface 11, groove 12, first die body 21, initial pier groove 22, initial pier bottom die pin 23, initial pier spring 24, second die body 31, final pier bottom die pin 32, final pier groove 33, final pier spring 34, die head 35, substrate part 52, alloy layer 51. DETAILED DESCRIPTION

[0020] Embodiment 1:

[0021] like Figures 1 to 3As shown, the rivet-type contact forming die of the utility model comprises a bottom die 1, a first die 2 and a second die 3. The bottom die 1 is provided with a flat forming surface 11 for placing contact materials, and the forming surface 11 is provided with at least one groove 12. The first die 2 cooperates with the forming surface 11 to perform pre-pier welding on the contact material on the forming surface 11. The second die 3 comprises a second die body 31. The second die body 31 is provided with a terminal pier groove 33 for cooperating with the forming surface 11 to perform terminal pier forming on the contact material on the forming surface 11. The diameter of the terminal pier groove 33 is set according to the outer diameter of the contact. The terminal pier groove 33 is provided with a terminal pier bottom die pin 32 that is slidably matched with the terminal pier groove 33, and the end surface of the terminal pier bottom die pin 32 forms the bottom surface of the terminal pier groove 33. A terminal pier spring 34 is provided between the second die body 31 and the terminal pier bottom die pin 32 to make the terminal pier bottom die pin 32 slide toward the opening of the terminal pier groove 33.

[0022] The end surface of the terminal bottom mold pin 32 can be a flat surface or an inner concave surface, which is specifically set according to the head structure of the contact product.

[0023] Among them, the first die 2 can be an ordinary solid punch, and the alloy layer in the contact material 5 on the forming surface 11 is pressed and connected with the base material part by the cooperation between the end face of the punch and the forming surface 11.

[0024] When the mold of the utility model is used, the bottom mold 1 is installed on the workbench of the cold heading machine, and the first mold 2 and the second mold 3 are respectively installed on the movable mold base 4 of the cold heading machine. The cold heading machine controls the movable mold base 4 to move up and down or left and right, thereby realizing the cooperation between the first mold 2 and the forming surface 11 or the cooperation between the second mold 3 and the forming surface 11.

[0025] like Figure 1 As shown, the forming process of the pie-shaped rivet-type electrical contact:

[0026] First, the base material 52 and the alloy layer 51 of the contact material 5 are placed at predetermined positions on the forming surface 11 by a person or a feeding mechanism, and then the movable die holder 4 is controlled to move downward by a cold heading machine, so that the first die 2 is matched with the forming surface 11, and the alloy layer 51 and the base material 52 are cold-pressed and welded together;

[0027] The cold heading machine controls the movable die base 4 to move upward, so that the first die 2 is separated from the alloy layer 51;

[0028] The cold heading machine controls the movable die base 4 to move rightward, so that the second die 3 moves to the original first die 2 position;

[0029] The cold heading machine controls the movable die seat 4 to move downward to a proper position. During the downward movement of the movable die seat 4, the alloy layer 51 gradually enters the terminal pier groove 33 and pushes the terminal pier bottom die pin 32 to move upward and compress the terminal pier spring 34. The forgeable alloy layer 51 is pressed by the reaction of the terminal pier spring 34 to the terminal pier bottom die pin 32, and the upper ends of the alloy layer 51 and the substrate part 52 are gradually pressed, thereby forming a pancake-shaped contact.

[0030] The cold heading machine controls the movable die base 4 to move upward, and the terminal pier bottom die pin 32 moves downward under the action of the terminal pier spring 34, thereby pushing the contact out of the terminal pier groove 33 to complete demoulding.

[0031] The selection of the terminal spring 34 is very important. It should be neither too soft nor too hard. If it is too soft, it will not be demoulded normally, and if it is too hard, it will affect the contact pressing forming.

[0032] Since the pancake-shaped structure contact has a very small demoulding angle or no demoulding angle and no nail feet, which makes molding difficult, the utility model arranges a groove 12 on the bottom mold, which can allow part of the material of the base material to enter the groove 12 during a single die-stamping welding process, thereby fixing the contact material and preventing it from shifting, which is convenient for subsequent processing; and a terminal pier bottom mold pin 32 is arranged in the terminal pier groove 33 of the second die 3, and the terminal pier bottom mold pin 32 is slidably arranged in the terminal pier groove 33 through a terminal pier spring 34. The contact can be pressed and demoulded by the terminal pier bottom mold pin 32, which solves the problem of difficulty in demoulding due to a very small demoulding angle or no demoulding angle, and the structure is simple and the production efficiency is high.

[0033] The final pier bottom mold pin 32 can be made of various mold steels. If the final pier bottom mold pin 32 is too brittle, it is easy to have a gap during the production process, resulting in a defective product. Therefore, the final pier bottom mold pin 32 is preferably made of white steel.

[0034] Embodiment 2:

[0035] Based on the first embodiment of the utility model, the second die body 31 is embedded with a die head 35, and the terminal pier groove 33 is arranged in the die head 35. Compared with the method of directly setting the terminal pier groove 33 in the second die body 31, the above method can replace the die head 35 when the terminal pier groove 33 is damaged. The die head 35 is generally made of harder steel, and the die head 35 in the embodiment of the utility model is made of tungsten steel.

[0036] In order to better fix the contact material, in the embodiment of the utility model, the grooves 12 are multiple and arranged in a ring shape on the forming surface 11. The specific number of the grooves 12 is set according to the diameter of the contact. The larger the contact diameter, the more the number of grooves. The specific shape of the grooves 12 can be various shapes, such as: circular, square, triangular, etc. When the groove is circular, its diameter is generally 0.03-0.08mm and the depth is 0.3-0.5mm.

[0037] Embodiment 3:

[0038] Furthermore, if Figure 4 As shown, in the embodiment of the utility model, the primary die 2 includes a primary die body 21, and a primary pier groove 22 is provided in the primary die body 21. The size of the primary pier groove 22 is set accordingly according to the initial material size of the alloy layer 51 in the contact material 5, and its diameter is generally slightly larger than the initial material diameter of the alloy layer. A primary pier bottom mold pin 23 that slides with the primary pier groove 22 is provided in the primary pier groove 22, and the end surface of the primary pier bottom mold pin 23 forms the bottom surface of the primary pier groove 22. A primary pier spring 24 that enables the primary pier bottom mold pin 23 to slide toward the opening of the primary pier groove 22 is provided between the primary pier bottom mold pin 23 and the primary die body 21. The primary pier groove 22 can be directly set in the primary die body 21, and can also be set in the primary die body 21 through an insert (see Figure 4 ).

[0039] During the pre-welding process of the first die 2 of the above structure, the upper ends of the alloy layer 51 and the substrate portion 52 gradually enter the first die groove 22 during the downward movement of the first die body 21, and push the first die bottom die needle 23 to compress the first die spring 24. Relying on the reaction of the first die spring 24, the alloy layer 51 and the substrate portion 52 can be cold-pressed and welded together. This structure can use the first die groove 22 to limit the relative position between the alloy layer 51 and the substrate portion 52, so that the connection between the alloy layer 51 and the substrate portion 52 in the contact material 5 can be better.

Claims

1. A rivet-type contact forming die, characterized in that: The invention comprises a bottom die (1), a first die (2) and a second die (3); the bottom die (1) is provided with a flat forming surface (11) for placing contact material, the forming surface (11) is provided with at least one groove (12), and the first die (2) cooperates with the forming surface (11) to perform pre-welding on the contact material on the forming surface (11); The second die (3) comprises a second die body (31), the second die body (31) being provided with a terminal pier groove (33) for cooperating with the forming surface (11) to perform terminal pier molding on the contact material on the forming surface (11), the terminal pier groove (33) being provided with a terminal pier bottom die pin (32) for slidably cooperating with the terminal pier groove (33), and a terminal pier spring (34) for causing the terminal pier bottom die pin (32) to slide toward an opening of the terminal pier groove (33) being provided between the second die body (31) and the terminal pier bottom die pin (32).

2. A rivet-type contact forming die according to claim 1, characterized in that: A die head (35) is embedded in the secondary die body (31), and the terminal pier groove (33) is arranged in the die head (35).

3. A rivet-type contact forming die according to claim 1, characterized in that: The grooves (12) are multiple and arranged in an annular shape on the forming surface (11).

4. A rivet-type contact forming die according to claim 1 or 3, characterized in that: The groove (12) is circular, has a diameter of 0.03-0.08 mm, and a depth of 0.3-0.5 mm.

5. The rivet-type contact forming die according to claim 1, characterized in that: The first die (2) comprises a first die body (21), a first die groove (22) is provided in the first die body (21), a first die bottom die pin (23) slidably matched with the first die groove (22) is provided in the first die groove (22), and a first die spring (24) is provided between the first die bottom die pin (23) and the first die body (21) to enable the first die bottom die pin (23) to slide towards the opening of the first die groove (22).

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