Arc-shaped punching die
By setting an arc surface and an inverted trapezoidal main die core in the punching die, the problem of material fracture in the forming of arc-shaped holes in small precision blanking parts is solved, achieving high-quality transition surface forming and improving processing efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-21
- Publication Date
- 2026-04-03
AI Technical Summary
Existing technologies cannot effectively prevent instantaneous material breakage at the hole and edge during the punching process, resulting in poor surface quality, especially in the forming of arc-shaped holes in small precision blanking parts.
By using an arc-shaped punching die, a circular arc surface is set on the outer periphery of the punch to contact the arc edge of the workpiece. Combined with an inverted trapezoidal main die core and a positioning plate, coaxiality and stroke accuracy are ensured, and a smooth transition surface is formed.
It improves the forming quality of arc-shaped holes in small precision blanking parts, enhances the smoothness of material transition surfaces and processing efficiency, and reduces the risk of material fracture.
Smart Images
Figure CN224073134U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of precision stamping of fasteners, and in particular to an arc-shaped punching die. Background Technology
[0002] For small precision stamping parts, the structural design of the punching die directly affects the product forming quality and processing efficiency. Figure 1 On the workpiece 10 shown, the hole 11 has a smooth, arc-shaped transition edge 12. Under normal circumstances, the arc transition that requires high precision needs to be formed by machining. Although this structure can also be achieved by flattening and punching, the material at the hole 11 and the edge 12 breaks instantly during the punching process, which can easily cause poor surface quality. Utility Model Content
[0003] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0004] An arc-shaped punching die includes a punch bar slidably arranged within the die, the punch bar having a first part and a second part with unequal outer diameters, and an arc surface on the outer side wall of the second part that contacts the arc edge of the workpiece during pressing.
[0005] In a preferred embodiment of this utility model, the arc surface is an arc concave towards the center of the punch axis, and the radius of the arc is R2.
[0006] In a preferred embodiment of the present invention, the punch is slidably disposed in the sliding cavity of the die, the sliding cavity being provided with a stepped surface for stopping the first part, and the second part passing through the stepped surface into the front section of the sliding cavity.
[0007] In a preferred embodiment of the present invention, a main mold opposite to the punch is further included, a main mold core is provided inside the main mold core, and the workpiece is placed inside the main mold core to be punched by the punch.
[0008] In a preferred embodiment of the present invention, the longitudinal section of the main mold core is trapezoidal, and the width of the upper surface of the main mold core is greater than the width of the lower surface.
[0009] In a preferred embodiment of this utility model, a material drop hole is provided at the bottom of the main mold core.
[0010] In a preferred embodiment of this utility model, the main mold core is made of tungsten steel.
[0011] In a preferred embodiment of the present invention, a positioning plate is further provided on the side of the die, and the punch passes through the positioning plate and the main die in sequence to perform punching.
[0012] The beneficial effects of this utility model are as follows:
[0013] The present invention provides an arc-shaped punching die, which improves the forming quality of the transition surface in two ways: First, an arc surface is arranged on the outer periphery of the punch, and the arc surface is used to smoothly expand the hole at the end of the stroke; Second, the cross section of the main die core is set to an inverted trapezoidal shape to improve the coaxiality deviation during filling; Finally, the stroke accuracy of the punch is improved by adding a positioning plate. Attached Figure Description
[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0015] Figure 1 This is a sectional view of the workpiece.
[0016] Figure 2 This is a cross-sectional view of the punching die of this utility model.
[0017] Figure 3 yes Figure 2 Enlarged view of part A.
[0018] Figure 4 This is a cross-sectional schematic diagram of the punching die of this utility model. Detailed Implementation
[0019] In the description of this utility model, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. The above description is for the purpose of simplifying the description of this utility model and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this utility model.
[0020] Unless otherwise specified, the singular forms “a,” “the,” and “the” used in this specification include the plural forms. The terms “comprising,” “including,” and “containing” used in this specification indicate the presence of the claimed feature but do not exclude the presence of one or more other features. The term “and / or” used in this specification includes any and all combinations of one or more of the relevant listed items.
[0021] When a component is described in the specification as being "on", "fixed" to, "connected" to, or "joined" to another component, the component may be directly located on, fixed to, connected to, joined to, or in contact with the other component, or there may be an intermediate component present.
[0022] It is understood that although the terms "first," "second," etc., may be used herein to describe different elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. Therefore, a first element may be referred to as a second element without departing from the teachings of this application.
[0023] Exemplary embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that this application can be presented in many different ways and is not limited to the embodiments described below. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide further additional embodiments. Throughout the drawings, the same reference numerals denote the same or functionally identical elements.
[0024] Figure 2 and Figure 3 The punching die portion of this punching die is shown. The punch 20 has a through sliding cavity 24, within which the punch 21 slides. The punch 21 has a first portion 22 near the rear end and a second portion 23 near the front end. The outer diameters of the first portion 22 and the second portion 23 are different, with the outer diameter of the first portion 22 being larger than that of the second portion 23. A stepped surface 25 is provided within the sliding cavity 24. When the punch 20 is placed within the sliding cavity 24 and slides forward, the contact point between the first portion 22 and the stepped surface 25 represents the maximum stroke of the punch 21. At this point, the forming end face 23b of the front end of the second portion 23 extends from the front end 26 to punch the workpiece 10.
[0025] An arc surface 23a is provided on the outer peripheral surface of the second part 23. This arc surface 23a is concave towards the axis of the punch 21, so that it contacts and presses against the arc edge 12 of the end face of the hole 11 during the punching of the workpiece 10, forming a smoother transition surface. Preferably, the fillet radius of the arc surface 23a is R2.
[0026] Figure 4 This diagram illustrates the fit between the punch and the main die. The main die 30 contains a main die core 31 to support the workpiece 10. The main die core 31 has an inverted trapezoidal vertical cross-section, with its upper surface wider than its lower surface. Due to the unavoidable small gap between the main die core 31 and the main die 30, the inverted trapezoidal structure allows for slight movement of the main die core 31, as long as its outer contour is coaxial with the punch 21. A blanking hole 32 is also provided at the bottom of the main die core 31 to discharge waste material during punching.
[0027] On the other hand, in order to match the inverted trapezoidal main mold core 31, a positioning plate 40 is also provided on one side of the punch 20. The punch 21 passes through the positioning plate 40 and then enters the main mold 30, ensuring the coaxiality of the punch 21 during the movement.
[0028] In a preferred embodiment, the main mold core 31 is made of tungsten steel.
Claims
1. An arcuate piercing die characterized by, The punch rod with sliding arrangement in the punch die comprises a first part and a second part with different outer diameters, and a circular arc surface is arranged on the outer wall of the second part to contact the workpiece arc edge during pressing.
2. An arcuate piercing die as claimed in claim 1, wherein, The circular arc surface is a concave circular arc towards the center of the punch rod, and the fillet of the circular arc is R2.
3. An arcuate piercing die as defined in claim 1, wherein, The punch rod is slidably arranged in the sliding cavity of the punch die, and a step surface is arranged in the sliding cavity to stop the first part, and the second part passes through the step surface to enter the front section of the sliding cavity.
4. An arcuate piercing die according to any one of claims 1 to 3, wherein A main die opposite to the punch die is also included, and a main die core is arranged in the main die to receive the pressing of the punch rod.
5. An arcuate piercing die as claimed in claim 4, wherein, The longitudinal section of the main die core is trapezoidal, and the upper surface of the main die core is wider than the lower surface.
6. An arcuate piercing die as defined in claim 4 wherein, A blanking hole is arranged at the bottom of the main die core.
7. An arcuate piercing die as defined in claim 4 wherein, The material of the main die core is tungsten steel.
8. An arcuate piercing die as defined in claim 4 wherein, A positioning plate is arranged on the side of the punch die, and the punch rod passes through the positioning plate and the main die in sequence to perform pressing.