Cold heading die

Abstract

The utility model provides a cold heading die, and belongs to the technical field of dies. The cold heading die comprises a die shell and a die core, the die core is installed in the die shell, a cavity is formed in the die core, a punch is arranged at the lower end of the die shell, a cold channel is formed in the inner wall of the die shell, the punch movably blocks one end of the cold channel, and the other end of the cold channel is communicated with an external cold air device. And an air channel is formed in the side wall of the mold core in a penetrating manner. In the application, the outer wall of the mold core is cooled by utilizing the cold channel formed in the inner wall of the mold shell, one end of the cold channel is firstly blocked by utilizing the punch, so that air in the cold channel can be sucked into the cavity when a product is demolded, and after the punch and the product completely leave the mold shell, air flows in the cold channel and the cavity are exhausted together, so that the heat dissipation of the inner wall of the cavity is realized; and in addition, the air channel is used for communicating the cold channel with the cavity, the air compression ratio can be reduced, the internal pressure of the cavity during cold heading is reduced, and therefore the cold heading effect is improved.

Description

Technical Field

[0001] The present application relates to the field of mold technology, and in particular to a cold heading mold. Background Art

[0002] During the cold heading process, the deformation of the metal material will release a large amount of heat energy. Excessive heat will greatly reduce the service life of the mold and cause thermal expansion and contraction of the product design dimensions.

[0003] In this regard, China's patent application number CN201820138852.0 discloses a forced cooling structure for a cold heading mold. This solution mainly involves evenly spirally wrapping a copper tube on the core of the main mold, with cooling water flowing through the copper tube to cool the cold heading mold.

[0004] However, in the process of implementing the technical solutions in the embodiments of the present application, the inventors of the present application discovered that the above technology has at least the following technical problems:

[0005] In order to facilitate product replacement, the mold core is usually installed in the mold shell, and the copper tube can only be wrapped around the outside of the mold shell. The heat of cold heading is mainly concentrated on the inner wall of the mold core, resulting in limited cooling effect. Utility Model Content

[0006] In order to make up for the above deficiencies, the present application provides a cold heading die, which aims to improve the problems mentioned in the above background technology.

[0007] An embodiment of the present application provides a cold heading mold, comprising a mold shell and a mold core, the mold core being installed in the mold shell, a mold cavity being provided in the mold core, a punch being provided at the lower end of the mold shell, a cold channel being provided on the inner wall of the mold shell, the punch being movably sealed at one end of the cold channel, the other end of the cold channel being connected to an external cooling device, an air channel being provided through the side wall of the mold core, and the mold cavity being connected to the cold channel through the air channel.

[0008] In a specific embodiment, a locking block is screwed to the lower end of the mold shell, and the locking block is movably pressed against the lower end of the mold core.

[0009] In the above implementation process, after the mold core is installed into the mold shell, the locking block is screwed in to fix the mold core.

[0010] In a specific embodiment, the locking block is a hollow structure, a tool withdrawal groove is provided at the threaded inner end of the mold shell, a through hole is provided through the side wall of the locking block, the cold channel is connected to the inner cavity of the locking block through the tool withdrawal groove and the through hole, and the punch is movably sealed in the through hole.

[0011] In the above implementation process, the tool retreat groove is naturally generated when machining the thread. The annular tool retreat groove and the through hole are used to guide the cold air in the airway into the inner cavity of the locking block, so that the punch can be movably blocked.

[0012] In a specific embodiment, the cooling channel is spirally opened on the inner wall of the mold shell, and the side of the cooling channel is open.

[0013] In the above implementation process, after the mold core is installed in the mold shell, the open cooling channel becomes a closed cooling channel. The cold air fully contacts the mold core along the spiral cooling channel, which is conducive to heat dissipation. The open cooling channel is also easy to clean.

[0014] In a specific embodiment, an interface is provided at the air inlet end of the cold channel.

[0015] In the above implementation process, the interface is used to connect to an external cooling device.

[0016] In a specific embodiment, the mold core fits the conical surface of the inner wall of the mold shell.

[0017] In the above implementation process, the conical surface fitting can be self-centered, which is also beneficial to the airtightness of the fitting between the mold core and the inner wall of the mold shell.

[0018] In a specific embodiment, the mold core includes an upper mold, a middle mold and a lower mold, the upper mold is a rod-shaped cavity, the middle mold is a hexagonal cavity, and the lower mold is the punch adapter cavity.

[0019] In the above implementation process, the raw material enters the lower die from the upper end and stops, and the punch impacts the upper end surface of the lower die from the bottom to cold-forge the raw material into a rod-shaped structure with a hexagonal head.

[0020] In a specific embodiment, the air channel is provided on the lower end surface of the upper mold and the upper end surface of the lower mold.

[0021] In the above implementation process, the air in the mold core can pass through the air channel into the cold channel during impact, which can avoid the internal air pressure being too high and affecting the effect of cold heading. It should be noted that if the air in the cavity cannot be discharged in time, the compression ratio will be very large, resulting in very high pressure, which will affect the cold heading effect. By connecting the cavity with the cold channel, the total air volume can be increased, the air compression ratio can be greatly reduced, and thus the pressure can be reduced. A low static pressure air cooler can be used here to avoid excessive pressure when the cold channel is blocked, which will affect the air in the cavity from overflowing from the air channel.

[0022] Compared with the prior art, the beneficial effects of the present application are: using the cold channel opened on the inner wall of the mold shell to cool the outer wall of the mold core, using the punch to first block one end of the cold channel, so that the air in the cold channel can be sucked into the cavity when the product is demolded, and when the punch and the product completely leave the mold shell, the air flow in the cold channel and the cavity is discharged together to achieve heat dissipation of the inner wall of the cavity, thereby improving the heat dissipation effect, and using the air channel to connect the cold channel and the cavity can reduce the air compression ratio and reduce the internal pressure of the cavity during cold forging, thereby improving the cold forging effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the implementation methods of the present application, the following is a brief introduction to the drawings required for use in the implementation methods. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 This is a schematic diagram of a cold heading die provided in an embodiment of the present application from a first perspective;

[0025] Figure 2 A schematic diagram of a cold heading die from a second perspective provided in an embodiment of the present application;

[0026] Figure 3 A schematic cross-sectional view of a cold heading die provided in an embodiment of the present application;

[0027] Figure 4 Schematic diagram of the connection between the mold core and the airway provided in the embodiment of the present application.

[0028] In the figure: 10 - mold shell; 20 - mold core; 21 - upper mold; 22 - middle mold; 23 - lower mold; 30 - punch; 40 - cooling channel; 50 - air channel; 60 - locking block; 70 - tool recess; 80 - through hole; 90 - interface. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0030] See also Figures 1-4The present application provides a cold heading mold, including a mold shell 10 and a mold core 20. The mold core 20 is installed in the mold shell 10. A cavity is provided in the mold core 20. A punch 30 is provided at the lower end of the mold shell 10. A cold channel 40 is provided on the inner wall of the mold shell 10. The punch 30 is movably sealed at one end of the cold channel 40. The other end of the cold channel 40 is connected to an external cooling device. An air channel 50 is opened through the side wall of the mold core 20, and the cavity is connected to the cold channel 40 through the air channel 50. Among them, the cold channel 40 opened on the inner wall of the mold shell 10 is used to cool the outer wall of the mold core 20, and the punch 30 is used to first block one end of the cold channel 40, so that the air in the cold channel 40 can be sucked into the cavity when the product is demolded. When the punch 30 and the product completely leave the mold shell 10, the cold channel 40 and the air flow in the cavity are discharged together to achieve heat dissipation of the inner wall of the cavity, thereby improving the heat dissipation effect, and the air channel 50 is used to connect the cold channel 40 and the cavity, which can reduce the air compression ratio and reduce the internal pressure of the cavity during cold forging, thereby improving the cold forging effect.

[0031] See also Figures 1-4 The lower end of the mold shell 10 is screwed with a locking block 60, and the locking block 60 is movable against the lower end of the mold core 20. After the mold core 20 is installed into the mold shell 10, the locking block 60 can be screwed in to fix the mold core 20.

[0032] See also Figures 1-4 The locking block 60 is a hollow structure. A tool-relief groove 70 is provided at the threaded inner end of the mold shell 10. A through-hole 80 is provided through the side wall of the locking block 60. The cold channel 40 communicates with the inner cavity of the locking block 60 through the tool-relief groove 70 and the through-hole 80. The punch 30 is movably sealed in the through-hole 80. The tool-relief groove 70 is naturally generated during thread machining. The annular tool-relief groove 70 and the through-hole 80 are used to guide the cold air in the air channel 50 into the inner cavity of the locking block 60, allowing the punch 30 to movably seal the through-hole 80.

[0033] See also Figures 1-4 The cooling channel 40 is spirally opened on the inner wall of the mold shell 10 and is open on the side. After the mold core 20 is installed in the mold shell 10, the open cooling channel 40 becomes a closed cooling channel 40. The cold air along the spiral cooling channel 40 fully contacts the mold core 20, which is conducive to heat dissipation. The open cooling channel 40 is also easy to clean.

[0034] See also Figures 1-4 The air inlet end of the cold channel 40 is provided with an interface 90. The interface 90 is used for connecting an external cooling device.

[0035] See also Figures 1-4 , the mold core 20 fits in with the conical surface of the inner wall of the mold shell 10. The conical surface fit can be self-centered, which is also beneficial to the airtightness of the fit between the mold core 20 and the inner wall of the mold shell 10.

[0036] See also Figures 1-4The core 20 includes an upper die 21, a middle die 22, and a lower die 23. The upper die 21 has a rod-shaped cavity, the middle die 22 has a hexagonal cavity, and the lower die 23 accommodates the punch 30. The raw material enters the lower die 23 from the top and stops. The punch 30 strikes the upper end surface of the lower die 23 from below, cold-forging the raw material into a rod-shaped structure with a hexagonal head.

[0037] See also Figures 1-4 The lower end surface of the upper mold 21 and the upper end surface of the lower mold 23 are both provided with an air channel 50. During impact, the air in the mold core 20 can pass through the air channel 50 and enter the cold channel 40, which can prevent the internal air pressure from being too high and affecting the effect of cold heading. It should be noted that if the air in the cavity cannot be discharged in time, the compression ratio will be very large, and a very high pressure will be generated, which will affect the cold heading effect. By connecting the cavity with the cold channel 40, the total air volume can be increased, the air compression ratio can be greatly reduced, and thus the pressure can be reduced. A low-pressure air cooler can be used here to avoid excessive pressure when the cold channel 40 is blocked, which will affect the air in the cavity from overflowing from the air channel 50.

[0038] The working principle of the cold heading die is as follows: the punch 30 is connected to the impact mechanism below, and after the die core 20 is installed into the die shell 10, the locking block 60 is screwed in to fix the die core 20. After the die core 20 is installed into the die shell 10, the open cold channel 40 becomes a closed cold channel 40, and the cold air fully contacts the die core 20 along the spiral cold channel 40, which is conducive to heat dissipation. The open cold channel 40 is also easy to clean. During cold heading, the raw material enters the lower die 23 from the upper end and stops. The punch 30 impacts the position of the upper end surface of the lower die 23 from the bottom to the upper end surface of the lower die 23, and the raw material is cold headed into a rod-shaped structure with a hexagonal head. The air in the die core 20 can pass through the air channel 50 into the cold channel 40, which can avoid the internal air pressure being too high to affect the effect of cold heading. When the punch 30 leaves downward, the upper end of the product is cut off and pushed downward by the subsequent material. When the hexagonal head enters the lower die 23, the middle die 2 2 increases, and the air in the cold channel 40 flows into the cavity through the air channel 50, absorbing the heat from the inner wall of the cavity. Then, the product is demolded from the bottom of the mold shell 10 following the punch 30. At this time, the through hole 80 is opened, and the air in the air channel 50 and the cavity begins to flow rapidly and is discharged from the through hole 80, which has the effect of dissipating heat both inside and outside the mold core 20. In summary, the cold channel 40 opened on the inner wall of the mold shell 10 is used to cool the outer wall of the mold core 20, and the punch 30 is used to first block one end of the cold channel 40 so that the air in the cold channel 40 can be sucked into the cavity when the product is demolded. When the punch 30 and the product completely leave the mold shell 10, the air flow in the cold channel 40 and the cavity is discharged together to achieve heat dissipation of the inner wall of the cavity, thereby improving the heat dissipation effect. In addition, the air channel 50 is used to connect the cold channel 40 and the cavity, which can reduce the air compression ratio and reduce the internal pressure of the cavity during cold heading, thereby improving the cold heading effect.

[0039] The above are merely examples of the present application and are not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modifications, improvements, or equivalent replacements made within the spirit and principles of the present application shall be included in the scope of protection of the present application. It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures.

Claims

1. A cold heading die, comprising a die shell (10) and a die core (20), wherein the die core (20) is installed in the die shell (10), a die cavity is provided in the die core (20), and a punch (30) is provided at the lower end of the die shell (10), characterized in that: A cooling channel (40) is provided on the inner wall of the mold shell (10), the punch (30) is movably sealed at one end of the cooling channel (40), and the other end of the cooling channel (40) is connected to an external cooling device. An air channel (50) is provided through the side wall of the mold core (20), and the mold cavity is connected to the cooling channel (40) through the air channel (50).

2. A cold heading die according to claim 1, characterized in that: The lower end of the mold shell (10) is screwed with a locking block (60), and the locking block (60) is movably pressed against the lower end of the mold core (20).

3. A cold heading die according to claim 2, characterized in that: The locking block (60) is a hollow structure, a tool-retracting groove (70) is provided at the threaded inner end of the mold shell (10), a through hole (80) is provided through the side wall of the locking block (60), the cold channel (40) is connected to the inner cavity of the locking block (60) through the tool-retracting groove (70) and the through hole (80), and the punch (30) is movably sealed in the through hole (80).

4. A cold heading die according to claim 3, characterized in that: The cooling channel (40) is spirally opened on the inner wall of the mold shell (10), and the cooling channel (40) is open on the side.

5. A cold heading die according to claim 4, characterized in that: The air inlet end of the cold channel (40) is provided with an interface (90).

6. A cold heading die according to claim 5, characterized in that: The mold core (20) is fitted with the conical surface of the inner wall of the mold shell (10).

7. A cold heading die according to claim 6, characterized in that: The mold core (20) includes an upper mold (21), a middle mold (22) and a lower mold (23); the upper mold (21) is a rod-shaped cavity, the middle mold (22) is a hexagonal cavity, and the lower mold (23) is an adapter cavity for the punch (30).

8. A cold heading die according to claim 7, characterized in that: The air passage (50) is provided on the lower end surface of the upper die (21) and the upper end surface of the lower die (23).

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