Punching die for punching coaxial small hole opposite to large hole of square tube
By designing the upper and lower dies, the punching die structure for large and small holes in square tubes is simplified. The concentricity is ensured by using the die cavity and elastic components, which solves the problems of complex punching dies and insufficient concentricity in the existing technology, and achieves cost reduction and improved processing accuracy.
Patent Information
- Application Number
- CN202423168119.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2034-12-20
AI Technical Summary
The existing die structures for processing large and small holes in square tubes are complex and cannot guarantee the concentricity of the large and small holes.
The design employs an upper and lower die assembly. The lower die assembly's concave die is positioned within the large hole of the square tube, and the height of the concave die is equal to the sum of the inner wall spacing and the wall thickness. An elastic element is used for unloading, simplifying the die structure and ensuring concentricity.
It reduces the manufacturing cost of stamping dies, simplifies the operation process, improves the concentricity of large and small holes, and reduces the reliance on operational skills.
Smart Images
Figure CN223655855U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of stamping die technology, and in particular to a stamping die for punching a small coaxial hole on the opposite side of a large hole in a square tube. Background Technology
[0002] See appendix Figure 1 As shown, during the machining process, concentric large and small holes need to be machined on the two opposite side walls of the square tube using a punch press;
[0003] See appendix Figure 2 and attached Figure 3 As can be seen from the existing processing procedures, when processing large and small holes on square tubes, the large holes are first processed by punching die A. Punching die A includes a lower template, a die core, a height compensation plate, a punch rod A, and a positioning pin. When punching, the square tube is first fitted onto the die core, and then the punching press drives the punch rod A to press down to obtain the large hole.
[0004] Next, the small hole is processed using die B. The square tube with the large hole is flipped 180 degrees to the other side and fitted onto the die core. The square tube is positioned using a locating pin, and the punch is used to drive the punch rod B downward to obtain the small hole.
[0005] However, the large and small holes obtained by the above processing method have the following problems: 1. The punching die A and punching die B include multiple parts, and their structure is too complicated, which leads to increased manufacturing costs;
[0006] 2. When machining small holes, the front-to-back positioning and left-to-right positioning of the square tube are two independent processes. The front-to-back positioning of the square tube relies on the positioning pin. If the end face of the square tube is tilted and the large hole and small hole are punched in two separate processes, the end face that is close to the positioning pin will be different when the square tube is flipped back and forth, which will cause front-to-back positioning error.
[0007] The left and right positioning of the square tube relies on the width of the mold core. In order for the square tube to be inserted and removed smoothly, the width of the mold core must be less than the distance between the inner walls of the square tube. This creates a gap between the inner wall of the square tube and the mold core, causing left and right wobbling and resulting in left and right positioning errors. Ultimately, the concentricity of the large hole and the small hole cannot be guaranteed.
[0008] Therefore, there is an urgent need for a punching die for punching a coaxial small hole on the opposite side of a large hole in a square tube, in order to simplify the structure of the punching die itself, reduce manufacturing costs, and ensure the concentricity of the large hole and the small hole. Utility Model Content
[0009] To address the aforementioned technical problems, this utility model provides a punching die for punching a coaxial small hole on the opposite side of a large hole in a square tube, thereby solving the problems of complex structure and inability to guarantee the concentricity of the large and small holes in existing punching dies for processing large and small holes in square tubes.
[0010] The above-mentioned technical objective of this utility model is achieved through the following technical solution:
[0011] A punching die for punching a coaxial small hole opposite a large hole in a square tube includes an upper die assembly and a lower die assembly. The upper die assembly includes a die shank, a retaining seat is bolted to the die shank, and a punch is installed inside the retaining seat.
[0012] The lower module includes a base, on which a concave mold is provided. The concave mold can be inserted into the large hole of the square tube and positioned for the processing of the small hole. The height of the concave mold is equal to the sum of the distance between the two inner walls of the square tube and the wall thickness.
[0013] The concave die has an insertion cavity along the axial direction, the insertion cavity can accommodate the diameter of the punch, and the depth to which the punch is inserted into the insertion cavity is greater than the wall thickness of the square tube.
[0014] Furthermore, an elastic element is fitted onto the punch, which is used to achieve unloading by means of a reverse elastic force.
[0015] Furthermore, the die and the base are detachably connected.
[0016] Furthermore, the base has a fixing hole at the position of the die, and the die has a connecting part at the joint with the base, and the connecting part is interference-fitted with the fixing hole.
[0017] Furthermore, the fixing hole is threadedly connected to the connecting part of the die.
[0018] Furthermore, the elastic element is a polyurethane rubber pad.
[0019] In summary, the beneficial technical effects of this utility model are as follows:
[0020] (1) When processing small holes in square tubes, large holes are first obtained by stamping with conventional dies. Then, the square tube is fitted onto the die through the large hole. At this time, the die not only supports the square tube during the small hole stamping, but also positions it. When processing small holes, there is no need to consider whether the end face of the square tube is flush, which ensures the concentricity of the large hole and the small hole. At the same time, by setting the die, the die core, positioning pin, and height compensation plate on the original die are replaced, which greatly simplifies the structure of the die and reduces the cost of die processing.
[0021] (2) By utilizing the elastic element, when the punch is pulled up after the small hole is processed, the elastic element can apply a downward thrust to the square tube to achieve the purpose of unloading, and prevent the square tube from being carried up with it. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the square tube structure;
[0023] Figure 2 This is a schematic diagram of the machining of a large hole using die A;
[0024] Figure 3 This is a schematic diagram of the small hole being machined using die B;
[0025] Figure 4 This is a schematic diagram of the structure of this utility model;
[0026] Figure 5 This is a schematic diagram of the small hole processing of this utility model;
[0027] Figure 6 yes Figure 5 A cross-sectional view of part A;
[0028] Figure 7 This is a schematic diagram showing the completed small hole machining.
[0029] Reference numerals: 1. Square tube; 2. Large hole; 3. Small hole; 4. Lower template; 5. Mold core; 6. Height compensation plate; 7. Punch A; 8. Punch B; 9. Positioning pin; 10. Stripper plate; 11. Stripper support tube; 12. Mold handle; 13. Retaining seat; 14. Punch; 15. Base; 16. Fixing hole; 17. Die; 18. Connecting part; 19. Positioning part; 20. Cavity; 21. Elastic element. Detailed Implementation
[0030] The present invention will now be described clearly and completely with reference to the embodiments.
[0031] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.
[0032] In the description of the embodiments, unless otherwise expressly specified and limited, the terms "set," "connect," etc., should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or a connection through an intermediate medium, or it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0033] See appendix Figure 1 The figure shows the specific structure of the square tube 1 to be processed, wherein concentric large holes 2 and small holes 3 are processed on two opposing side walls of the square tube 1.
[0034] See appendix Figure 2 and attached Figure 3The diagram shows the specific structure of the punching die A and punching die B used for processing the large hole 2 and small hole 3 of the existing square tube 1. Both punching die A and punching die B include a lower template 4. A die core 5 is installed on the lower template 4 by bolts. A height compensation plate 6 is sandwiched between the die core 5 and one end of the lower template 4. The height compensation plate 6 makes a feeding gap between the other end of the die core 5 and the lower template 4. The width of this feeding gap is greater than the wall thickness of the square tube 1. At the same time, a discharge plate 10 is bolted to the end of the lower template 4 located in the feeding gap by a discharge support pipe 11.
[0035] Currently, when processing the large hole 2, firstly, the square tube 1 is fitted onto one end of the mold core 5 and abuts against the positioning pin 9. Then, the punch A7 is installed on the punch press, and the punch press drives the punch A7 to press down to obtain the large hole 2. Then, the square tube 1 is flipped over and the punch B8 on the die B is used to obtain the small hole 3.
[0036] Therefore, it can be seen that when processing by the above-mentioned existing processing methods, not only are the structures of punches A and B too complex, including multiple parts, but the positioning of the square tube 1 when processing the large hole 2 and the small hole 3 is based on the end face of the square tube 1 and the mold core 5 as the reference. This makes the two positioning independent of each other and unrelated, so the concentricity of the large hole 2 and the small hole 3 cannot be guaranteed. Based on this problem, this utility model proposes a punch for punching the large hole 2 of the square tube 1 and the coaxial small hole 3 on the opposite side.
[0037] See appendix Figure 4-7 As shown, this utility model includes an upper module and a lower module. The upper module includes a die shank 12, which is used to connect with a punch. One end of the die shank 12 is bolted to a retaining seat 13. A punch 14 is inserted into the retaining seat 13. The retaining seat 13 can ensure the perpendicularity of the punch 14.
[0038] Meanwhile, the lower module includes a base 15, on which a fixing hole 16 is provided, and a cavity 17 is provided in the fixing hole 16. The cavity 17 includes a positioning part 19 and a connecting part 18. A step is machined on one end of the connecting part 18 near the positioning part 19. The connecting part 18 is used to connect with the fixing hole 16. During connection, the connecting part 18 can be pressed into the fixing hole 16 to achieve an interference fit, or the connecting part 18 and the fixing hole 16 can be connected by threads.
[0039] Furthermore, the positioning part 19 can be inserted into the large hole 2 of the square tube 1 without relative displacement between them, and the height of the positioning part 19 is equal to the sum of the distance between the two inner walls of the square tube 1 and a wall thickness. This ensures that when the large hole 2 is fitted onto the die 17, one end of the positioning part 19 abuts against the inner wall of the top of the square tube 1, providing support for the stamping of the small hole 3 and preventing deformation of the square tube 1 under stamping. Simultaneously, the positioning part 19 has an insertion cavity 20 along the axial direction, which can accommodate the diameter of the punch 14. The depth of cavity 20 is greater than the wall thickness of square tube 1. Cavity 20 is used to avoid the punch 14. When machining small hole 3, square tube 1 is first placed on the core 5 of punch A, and large hole 2 is machined by punch rod A7. Then, large hole 2 is fitted on die 17. Die 17 is used to position small hole 3 of square tube 1. Then, punch 14 is driven down by punch to obtain small hole 3. Since the position of small hole 3 is obtained by positioning with die 17 with large hole 2 as reference, the concentricity of large hole 2 and small hole 3 is guaranteed.
[0040] Therefore, by providing a die 17 on the base 15, the structure of the original punch B for processing small holes 3 is greatly simplified. At the same time, during positioning, there is no need to rely on the cooperation between the positioning pin 9 and the end face of the square tube 1. The positioning of the large hole 2 and the small hole 3 is linked by the die 17, ensuring their concentricity.
[0041] Furthermore, in order to prevent the square tube 1 from being pulled out during the rising process of the punch 14 after the small hole 3 is processed, an elastic element 21 is fitted on the punch 14. The elastic element 21 is specifically a polyurethane rubber pad, and one end of the elastic element 21 abuts against the bottom of the retaining seat 13. When the punch 14 is pressed down, it compresses the elastic element 21 to generate a reverse elastic force. When the punch 14 rises, the elastic element 21 pushes out the square tube 1 through the reverse elastic force to achieve unloading.
[0042] In use, the square tube 1 is first fitted onto the core 5 of the die A, and the punch A7 is pressed down by the punch press to obtain the large hole 2. Then the large hole 2 on the square tube 1 is fitted onto the die 17 in this utility model. At this time, the position of the small hole 3 is determined by the cooperation between the large hole 2 and the die 17. Then the punch 14 is pressed down by the punch press to obtain the small hole 3.
[0043] The structure of this utility model is simpler than the existing die B used for processing small holes 3, which reduces the manufacturing cost of the entire die. At the same time, the positioning of the large hole 2 and the small hole 3 is linked by the die 17. When the square tube 1 is fitted on the die 17, it can be placed at any angle and a small hole 3 concentric with the large hole 2 can be processed. This reduces the dependence on the structure of the die itself. More importantly, it reduces the skill level required of the operator and makes the die itself more applicable.
[0044] The above description is only a preferred embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model. Therefore, all equivalent changes made to the structure, shape and principle of the present utility model should be included within the scope of protection of the present utility model.
Claims
1. A punching die for punching a small coaxial hole opposite a large hole in a square tube, comprising an upper die assembly and a lower die assembly, characterized in that: The upper module includes a mold handle (12), a retaining seat (13) is bolted to the mold handle (12), and a punch (14) is installed inside the retaining seat (13); The lower module includes a base (15), and a die (17) is provided on the base (15). The die (17) can be inserted into the large hole (2) of the square tube (1) and positioned for the processing of the small hole (3). The height of the die (17) is equal to the sum of the distance between the two inner walls of the square tube (1) and the wall thickness. The concave die (17) has an insertion cavity (20) along the axial direction. The insertion cavity (20) can accommodate the diameter of the punch (14), and the depth to which the punch (14) is inserted into the insertion cavity (20) is greater than the wall thickness of the square tube (1).
2. The punching die for punching a coaxial small hole opposite a large hole in a square tube according to claim 1, characterized in that: An elastic element (21) is fitted on the punch (14), and the elastic element (21) is used to unload the material by means of reverse elastic force.
3. A punching die for punching a coaxial small hole opposite a large hole in a square tube according to claim 1, characterized in that: The die (17) and the base (15) are detachably connected.
4. A punching die for punching a coaxial small hole opposite a large hole in a square tube according to claim 1, characterized in that: The base (15) has a fixing hole (16) at the position of the die (17), and the die (17) has a connecting part (18) at the joint with the base (15), and the connecting part (18) is interference-fitted with the fixing hole (16).
5. A punching die for punching a coaxial small hole opposite a large hole in a square tube according to claim 4, characterized in that: The fixing hole (16) is threadedly connected to the connecting part (18) of the die (17).
6. A punching die for punching a coaxial small hole opposite a large hole in a square tube according to claim 2, characterized in that: The elastic element (21) is a polyurethane rubber pad.