Stamping and bending die for preventing product cracking and stamped part

Abstract

The utility model discloses a kind of stamping bending die and stamping part for preventing product cracking, stamping bending die for preventing product cracking includes pressing material into son;Forming punch, with pressing material into son setting at the same side of stamping part, forming punch has linear reciprocating freedom degree;Lower die into son, with the two sides of pressing material into son clamping stamping part;First forming top block and second forming top block, first forming top block is located at the inside angle of the bending of stamping part, first forming top block, second forming top block are located at the two sides of stamping part;First forming top block has first protruding part, second forming top block has second protruding part, first protruding part has convex surface, second protruding part has concave surface towards the side of first protruding part convex surface;The highest of first forming top block is the convex surface of first protruding part. The specified shape of circular arc is punched out at the bending of stamping part using the utility model, not rely on the natural bending of material, and the material cracking at bending is facilitated to control.

Description

Technical Field

[0001] This utility model relates to the field of stamping dies and stamping products, specifically to a stamping and bending die and stamping parts for preventing product cracking. Background Technology

[0002] In the production of bent stamped parts, there are certain problems with the stamping and bending process. When performing a 180° forming bend, it is usually done in four steps, namely... Figure 1 Bend at a 45° angle as shown, then... Figure 2 Make a 90° bend as shown, then... Figure 3 The diagram shows a 150° bend. Figure 4 This shows the details of the bend, and finally... Figure 5 The 180° bend shown is a gradual bending method. However, the final 180° bend is prone to cracking due to excessive material tension. This not only affects product quality but also poses safety risks after assembly. If the bent stamped part is a conductor such as a copper busbar, there is also a risk of open circuit insulation. Therefore, it is necessary to avoid breakage at the bend. Utility Model Content

[0003] The problem to be solved by this utility model is to provide a stamping and bending die and stamping parts that prevent product cracking.

[0004] To solve the above problems, this utility model provides a stamping and bending die and a stamped part to prevent product cracking. To achieve the above objectives, the technical solution adopted by this utility model to solve its technical problems is as follows: On one hand, a stamping and bending die for preventing product cracking includes: a blank holder; a forming punch disposed on the same side of the stamped part as the blank holder, the forming punch having linear reciprocating freedom; a lower die holder that clamps both sides of the stamped part with the blank holder; and forming top blocks, including a first forming top block and a second forming top block, the first forming top block being located at the inner corner of the bent portion of the stamped part, and the first forming top block and the second forming top block being located on both sides of the stamped part; wherein, the first forming top block has a first protrusion, the second forming top block has a second protrusion, the first protrusion has a convex curved surface, and the side of the second protrusion facing the convex curved surface of the first protrusion has a concave curved surface; the highest point of the first forming top block is the convex curved surface of the first protrusion.

[0005] As a further improvement of this utility model, the outer wall of the first protrusion is entirely a convex curved surface, and the degree of the supplementary angle of the central angle corresponding to the convex curved surface is less than the angle between the outer walls of the two sides of the first forming top block.

[0006] As a further improvement of this utility model, the corner of the pressing insert facing the first protrusion has a bevel.

[0007] As a further improvement of this utility model, the top of the second protrusion is a flat top surface.

[0008] As a further improvement of this utility model, the top of the second protrusion is at a higher height than the top of the first protrusion.

[0009] As a further improvement of this utility model, the angle between the inclined surface of the pressing insert and the horizontal plane is in the range of 20° to 25°.

[0010] As a further improvement of this utility model, the pressing insert is located above the first forming top block, the first forming top block and the second forming top block have a horizontal translational freedom in opposite directions, and the pressing insert has a vertical lifting freedom.

[0011] As a further improvement of this utility model, there are several forming punches and several lower die inserts, which are replaced synchronously.

[0012] On the other hand, a stamping part using the stamping and bending die for preventing product cracking as described above, the stamping part comprising: a first straight section and a second straight section, the junction of the first straight section and the second straight section being integrally connected by an arc section, wherein the degree measure of the supplementary angle corresponding to the central angle of the arc section is less than the degree measure of the angle formed by the first straight section and the second straight section.

[0013] As a further improvement of this utility model, one end of the arc segment is tangentially transitioned to the first straight segment, and the tangent direction of the other end of the arc segment forms an angle with the second straight segment.

[0014] The beneficial technical effects of using the stamping and bending die for preventing product cracking according to this application are: This mold, by setting a first forming top block with a convex curved surface at the inner corner of the bending point of the stamped part, and a second forming top block with a concave curved surface on the other side of the stamped part, can provide targeted support and adaptive constraint for the material at the bending point of the stamped part during the bending process. This avoids excessive stretching of the material due to concentrated bending force, effectively reducing the risk of cracks at the bending corner. Structurally, it directly solves the quality problem of easy cracking in 180° forming in traditional stamping and bending.

[0015] The forming punch has linear reciprocating freedom and can work with the blank holder and the lower die holder to clamp the stamped part on both sides, ensuring that the stamped part is stable in position and balanced in force during the bending process, avoiding local stress abnormalities caused by displacement or force deviation; at the same time, the curved surface design of the first and second forming top blocks is adapted to the bending shape of the stamped part. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the first bending state of one embodiment of the prior art; Figure 2 This is a schematic diagram of the second bending state according to an embodiment of the prior art; Figure 3 This is a schematic diagram of the third bending state in one embodiment of the prior art; Figure 4 This is a magnified view of part A in one embodiment of the prior art; Figure 5 This is a schematic diagram of the fourth bending state in one embodiment of the prior art; Figure 6 This is a schematic diagram of the bending state of one embodiment of the stamped part of this utility model; Figure 7 This is a partial enlarged view of section B of one embodiment of the stamped part of this utility model; Figure 8 This is a schematic diagram of the first operating state of one embodiment of the anti-cracking stamping and bending die of this utility model; Figure 9 This is a schematic diagram of the second operating state of one embodiment of the anti-cracking stamping and bending die of this utility model; Figure 10 This is a schematic diagram of the third operating state of one embodiment of the anti-cracking stamping and bending die of this utility model; Figure 11 This is a partial enlarged view of point C in one embodiment of the anti-cracking stamping and bending die of this utility model; Figure 12 This is a schematic diagram of the fourth operating state of one embodiment of the anti-cracking stamping and bending die of this utility model; Figure 13 This is an exploded view of the blank holder, the first forming top block, and the second forming top block of one embodiment of the anti-cracking stamping and bending die of this utility model. Figure 14 This is a partial enlarged view of point D in one embodiment of the anti-cracking stamping and bending die of this utility model; Figure 15 This is a schematic diagram of the bending state of one embodiment of the stamped part of this utility model.

[0018] 1-Forming punch; 11-First forming punch; 111-First active extrusion surface; 12-Second forming punch; 121-Second active extrusion surface; 2-Pressure insert; 21-Inclined surface; 3-Lower die insert; 31-First lower die insert; 311-First passive extrusion surface; 32-Second lower die insert; 321-Second passive extrusion surface; 4-Stamped part; 41-First straight section; 42-Second straight section; 43-Circular arc section; 44-First junction; 45-Second junction; 5-First forming top block; 51-First protrusion; 511-Convex curved surface; 6-Second forming top block; 61-Second protrusion; 611-Concave curved surface; 7-First pressure seam; 8-Second pressure seam; RK-Rounded corner crack; a1-Central angle; a2-Opening angle. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to specific embodiments: To achieve the purpose of this utility model, a stamping and bending die for preventing product cracking includes: a blank holder 2. A forming punch 1 and the blank holder 2 are disposed on the same side of the stamped part 4, and the forming punch 1 has linear reciprocating freedom. A lower die holder 3 and the blank holder 2 clamp the two sides of the stamped part 4. The forming top blocks include a first forming top block 5 and a second forming top block 6. The first forming top block 5 is located at the inner corner of the bent portion of the stamped part 4, and the first forming top block 5 and the second forming top block 6 are located on both sides of the stamped part 4. Figure 11 , Figure 14 As shown, the first molding top block 5 has a first protrusion 51, and the second molding top block 6 has a second protrusion 61. The first protrusion 51 has a convex curved surface 511, and the second protrusion 61 has a concave curved surface 611 on the side facing the convex curved surface 511 of the first protrusion 51. The highest point of the first molding top block 5 is the convex curved surface 511 of the first protrusion 51.

[0020] The difference between the fillet radius corresponding to the concave curved surface 611 and the fillet radius corresponding to the convex curved surface 511 is equal to the thickness of the stamped part 4.

[0021] The beneficial effects of adopting the above technical solution are as follows: By setting a first forming top block 5 with a convex curved surface 511 at the inner corner of the bending point of the stamping part 4 and a second forming top block 6 with a concave curved surface 611 on the outer side, the mold can form targeted support and adaptive constraint on the material at the bending point of the stamping part 4 during the bending process, thereby allowing the stamping part 4 to form a specified arc. This arc is not naturally formed during bending, but is specifically formed, so it is easy to control the radius of the rounded corner of the bending arc.

[0022] In some other embodiments of this utility model, the outer wall of the first protrusion 51 is entirely a convex curved surface 511, and the degree of the supplementary angle of the central angle corresponding to the convex curved surface 511 is less than the angle between the first forming top block 5 and the outer walls of the two adjacent sides of the first protrusion 51.

[0023] A supplementary angle represents two angles whose sum equals 180°.

[0024] The beneficial effect of adopting the above technical solution is that the arc shape that can be determined by the convex surface 511 and the concave surface 611 during bending can be determined by using the angular relationship.

[0025] In some other embodiments of this utility model, the pressure insert 2 has a bevel 21 at one corner facing the first protrusion 51.

[0026] The beneficial effects of adopting the above technical solution are: setting an inclined surface 21 at one corner of the pressure insert 2 facing the first protrusion 51 helps to guide the material to flow smoothly in the early stage of bending, reduces the friction and instantaneous stress between the material and the pressure insert 2, and reduces the possibility of surface scratches or tears.

[0027] In some other embodiments of this utility model, the top of the second protrusion 61 is a flat surface.

[0028] In some other embodiments of this utility model, the top of the second protrusion 61 is at a higher height than the top of the first protrusion 51.

[0029] The beneficial effect of adopting the above technical solution is that the top height of the second protrusion 61 is higher than that of the first protrusion 51, which allows the second forming top block 6 to contact and support the material before the first forming top block 5 during the bending process, forming a better stress distribution gradient and further suppressing cracking.

[0030] In some other embodiments of this utility model, the angle between the inclined surface 21 of the pressing insert 2 and the horizontal plane is in the range of 20° to 25°.

[0031] The beneficial effect of adopting the above technical solution is that the angle range is the result of optimization, which can best balance the material guiding effect and the pressing stability.

[0032] In some other embodiments of this utility model, the pressing insert 2 is located above the first forming top block 5, the first forming top block 5 and the second forming top block 6 have a horizontal translational degree of freedom in opposite directions, and the pressing insert 2 has a vertical lifting degree of freedom.

[0033] like Figure 13 , Figure 14As shown, the pressing insert 2, the first forming top block 5, and the second forming top block 6 are arranged in a three-point configuration. The first pressing groove 7 is formed between the pressing insert 2 and the first forming top block 5, and the second pressing groove 8 is formed between the second forming top block 6 and the first forming top block 5.

[0034] The beneficial effects of adopting the above technical solution are: by setting the pressure insert 2 to move vertically, and the first forming top block 5 and the second forming top block 6 to move horizontally towards each other, the coordinated action of the three can accurately control the material flow and forming trajectory during the bending process, ensuring the accuracy of the bending shape.

[0035] In some other embodiments of this utility model, there are several forming punches 1 and several lower die inserts 3, and the forming punches 1 and the lower die inserts 3 can be replaced synchronously.

[0036] like Figure 8 As shown, the forming punch 1 includes a first forming punch 11, and the lower die insert 3 corresponds to the first lower die insert 31. The bottom of the first forming punch 11 includes a first active extrusion surface 111, and the top of the first lower die insert 31 has a first passive extrusion surface 311. The first active extrusion surface 111 and the first passive extrusion surface 311 are parallel to each other. The two together achieve the first bending operation, bending the originally straight stamped part 4 at a 45° angle.

[0037] like Figure 9 As shown, the forming punch 1 includes a second forming punch 12, and the lower die insert 3 corresponds to the second lower die insert 32. One side of the second forming punch 12 includes a second active extrusion surface 121, and one side of the second lower die insert 32 has a second passive extrusion surface 321. The second active extrusion surface 121 and the second passive extrusion surface 321 are parallel to each other. The two together achieve a second bending operation, bending the stamped part 4 by 90°.

[0038] like Figure 10 , Figure 11 , Figure 6 As shown, the pressing insert 2, the first forming top block 5, and the second forming top block 6 work together to perform the third bending operation on the stamped part 4, bending the stamped part 4 at 142°.

[0039] like Figure 12 , Figure 15 As shown, in the fourth bending operation of stamped part 4, stamped part 4 is bent 180°. That is, stamped part 4 is bent from... Figure 7 Become Figure 8 The state.

[0040] The beneficial effects of adopting the above technical solution are: multiple forming punches 1 and lower die inserts 3 are provided and can be replaced synchronously, enabling the mold to efficiently and continuously complete multi-step bending processes, greatly improving production efficiency and mold applicability. Replacement can be achieved by replacing parts of the mold itself, but a more feasible approach is to replace the stamping parts 4 between different workstations, thus forming a relative replacement between the forming punches 1 and lower die inserts 3, allowing for distributed stamping and bending.

[0041] The stamped part 4 is processed from the stamping and bending die for preventing product cracking. The stamped part 4 includes: a first straight section 41 and a second straight section 42. The junction of the first straight section 41 and the second straight section 42 is integrally connected by an arc section 43. The degree of the supplementary angle corresponding to the central angle of the arc section 43 is less than the angle between the first straight section 41 and the second straight section 42.

[0042] That is, Figure 7 As shown, the supplementary angle of central angle a1 is greater than the angle a2. If the central angle of arc segment 43 is not specially designed, but is as follows... Figure 3 Then the degree measure of the supplementary angle is equal to the interior angle of the stamped part.

[0043] The beneficial effects of adopting the above technical solution are: the stamped part 4 connects two straight sections with an arc segment 43 at the bending point, and the supplementary angle of the central angle of the arc segment 43 is smaller than the included angle of the two straight sections, thereby increasing the actual radius of the rounded corner at the bending point, fundamentally dispersing the stress, and improving the crack resistance of the product.

[0044] In some other embodiments of this utility model, one end of the arc segment 43 is tangentially transitioned to the first straight segment 41, and the tangent direction of the other end of the arc segment 43 forms an angle with the second straight segment 42.

[0045] The beneficial effect of adopting the above technical solution is that the bending structure of this stamped part 4 cannot be tangential at both ends, so it maintains a shape with one tangential transition and the other non-tangential transition.

[0046] like Figure 7 As shown, the first junction 44 is the intersection of the first straight segment 41 and the arc segment 43, and the second junction 45 is the intersection of the second straight segment 42 and the arc segment 43. The first junction 44 is a straight transition, and the second junction 45 is also a rounded transition.

[0047] Figure 7 After further bending, it becomes similar to Figure 15 The state is due to the presence of arc segment 43. Figure 15 The bend is not easy to be like Figure 5 The RK also has cracking defects at the rounded corner crack.

[0048] This application's stamped part 4 increases the strength of the bending stress point by enlarging its own rounded corner structure, breaking the conventional forming structure and preventing the rounded corners from cracking easily. This eliminates the possibility of cracking during the forming of stamped part 4, reduces the risk of open circuit insulation after product assembly, and improves quality yield.

[0049] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it. They should not be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be covered within the protection scope of this utility model.

Claims

1. A stamping and bending die for preventing product cracking, characterized in that, include: Material feeder; A forming punch and a blank holder are located on the same side of the stamped part, and the forming punch has linear reciprocating freedom. The lower die insert and the blank holder clamp the two sides of the stamping part; The forming top block includes a first forming top block and a second forming top block. The first forming top block is located at the inner corner of the bend of the stamped part, and the first forming top block and the second forming top block are located on both sides of the stamped part. The first forming top block has a first protrusion, the second forming top block has a second protrusion, the first protrusion has a convex curved surface, and the side of the second protrusion facing the convex curved surface of the first protrusion has a concave curved surface. The highest point of the first molded top block is the convex curved surface of the first protrusion.

2. The stamping and bending die for preventing product cracking according to claim 1, characterized in that: The outer wall of the first protrusion is entirely a convex curved surface, and the degree measure of the supplementary angle of the central angle corresponding to the convex curved surface is less than the angle between the outer walls of the two sides of the first forming top block.

3. The press-bending die for preventing cracking of a product according to claim 1, characterized by: The corner of the pressing insert facing the first protrusion has a bevel.

4. The stamping and bending die for preventing product cracking according to claim 1, characterized in that: The top of the second protrusion is a flat surface.

5. The stamping and bending die for preventing product cracking according to claim 1, characterized in that: The top of the second protrusion is at a higher height than the top of the first protrusion.

6. The stamping and bending die for preventing product cracking according to claim 3, characterized in that: The angle between the inclined surface of the pressing insert and the horizontal plane ranges from 20° to 25°.

7. The stamping and bending die for preventing product cracking according to claim 1, characterized in that: The pressing insert is located above the first forming top block. The first forming top block and the second forming top block have a horizontal translational freedom in opposite directions, and the pressing insert has a vertical lifting freedom.

8. The stamping and bending die for preventing product cracking according to claim 1, characterized in that: The forming punch and the lower die insert each have several units, and they are replaced synchronously.

9. A stamped part, characterized by, Using any one of claims 1 to 8, the stamping and bending die for preventing product cracking, the stamped part includes: a first straight section and a second straight section, the junction of the first straight section and the second straight section is integrally connected by an arc section, the degree of the supplementary angle corresponding to the central angle of the arc section is less than the degree of the angle between the first straight section and the second straight section.

10. The stamped part of claim 9, characterized in that: One end of the arc segment is tangentially connected to the first straight segment, and the tangent direction of the other end of the arc segment forms an angle with the second straight segment.

Images