Sectional type ejector rod suitable for hot die forging belt wheel shaft die

Abstract

The utility model relates to a sectional type ejector rod suitable for a hot die forging belt wheel shaft die, which comprises an upper die part and a lower die part, an ejector rod element used for ejecting a workpiece is arranged in the lower die part, the top of the ejector rod element is contacted with the workpiece, and the bottom of the ejector rod element is used for bearing pressure generated in the hot forging process. The top and the bottom of the ejector rod element are detachably designed; by adopting the sectional structure, the service life of the ejector rod element is prolonged. When the contact end of the ejector rod element or the supporting end of the ejector rod element is abraded or damaged, only the corresponding part needs to be replaced, the whole ejector rod element does not need to be replaced, and the maintenance cost and the replacement cost are reduced.

Description

Technical Field

[0001] This utility model relates to the field of mold technology, specifically to a segmented ejector pin suitable for hot forging pulley shaft molds. Background Technology

[0002] Characteristics of hot forging process: Hot forging requires applying pressure to form a metal billet at a high temperature of approximately 800 to 1200 degrees Celsius. During the hot forging process, the ejector pin is used to eject the workpiece from the die. During ejection, the ejector pin 2 must withstand an ejection force of 200 to 500 tons, while also being subjected to frictional forces and thermal stresses generated by the shrinkage of the forging. During ejection, it is necessary to ensure that the dimensional tolerance of the forging is typically within ±0.2 mm, and to prevent deformation of the forging due to misalignment during ejection.

[0003] The authorization announcement number CN222660015U discloses an automatic line forging die for multiple automotive aluminum alloy control arms. According to its instruction manual and drawings, the following scheme is provided: the bottom of the lower die ejector is provided with a groove, and a multi-link ejector rod is installed in the groove. The lower end of the ejector rod is connected to an ejector rod tray by bolts. The ejector rod can simultaneously eject two products horizontally.

[0004] The top rod with this structure still has limitations. When a part of the top rod is damaged or worn, the entire top rod needs to be replaced, which increases production costs and replacement workload. Summary of the Invention

[0005] This invention addresses the problem of wear and tear on ejector pins during use by proposing a segmented ejector pin suitable for hot forging pulley shaft dies. The segmented structure improves the service life of the ejector pin component. When wear or damage occurs at the contact end or support end of the ejector pin, only the corresponding part needs to be replaced, rather than replacing the entire ejector pin component.

[0006] The purpose of this invention is achieved through the following technical solution: a segmented ejector pin suitable for hot forging pulley shaft mold, comprising an upper mold part and a lower mold part, wherein the lower mold part is provided with an ejector pin element for ejecting the workpiece, the top of the ejector pin element is in contact with the workpiece, the bottom of the ejector pin element is used to bear the pressure generated during hot forging, and the top and bottom of the ejector pin element are designed to be detachable.

[0007] Preferably, the push rod element includes a push rod contact end and a push rod support end. The push rod contact end has a circular through hole in the middle and a circular through hole on the side wall surface of the push rod contact end. The circular through hole of the push rod contact end is sleeved on the top of the push rod support end.

[0008] Preferably, the bottom of the top rod support end is shaped like a frustum, and a cylinder with a bevel extends upward from the frustum. The frustum and the cylinder are designed as a single unit, and the circular through hole at the contact end of the top rod is adapted to the top of the cylinder.

[0009] Preferably, the upper mold portion includes an upper mold core, an upper template, and an upper mold sleeve. The shape of the concave surface inside the upper mold core is the same as the top shape of the workpiece. The upper mold sleeve is fitted onto the side wall of the upper mold core, and the upper template is fitted onto the side wall of the upper mold sleeve.

[0010] Preferably, the lower mold portion includes a lower mold core, a lower mold sleeve, a first lower mold pad, and a second lower mold pad. The shape of the concave surface inside the lower mold core is the same as the shape of the middle and bottom of the workpiece. The bottom of the lower mold core is provided with a first lower mold pad and a second lower mold pad for raising it. The side walls of the lower mold core, the first lower mold pad, and the second lower mold pad are fitted with a lower mold sleeve, and the side walls of the lower mold sleeve are fitted with a lower template.

[0011] Preferably, the upper mold plate is connected to the upper fixed plate of the injection molding machine, and the lower mold plate is connected to the lower fixed plate of the injection molding machine. This installation arrangement is to facilitate the subsequent mold opening process.

[0012] Preferably, the bottom of the ejector rod support end is attached to the surface of the first lower mold pad, the bottom of the ejector rod contact end is attached to the surface of the second lower mold pad, and the top of the ejector rod support end passes through the through hole at the top of the second lower mold pad until it is inserted into the circular through hole in the middle of the ejector rod contact end.

[0013] Preferably, the interior of the second lower mold pad is provided with a clearance groove adapted to a frustum, the height of which is greater than the height of the frustum, and the push rod support end can slide up and down inside the second lower mold pad.

[0014] Preferably, the material of the ejector pin contact end is Oberduwa hot work die steel, and the material of the ejector pin support end is hot work die steel. This arrangement is to give the ejector pin contact end a better service life.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. By adopting a segmented structure, the service life of the push rod element is improved. When the push rod contact end or push rod support end is worn or damaged, only the corresponding part needs to be replaced, instead of replacing the entire push rod element, thus reducing maintenance and replacement costs;

[0017] 2. The special design of the push rod contact end and the use of wear-resistant materials improve the contact performance between the push rod element and shaft parts, reduce damage to parts, and improve product quality. The reasonable selection of materials for the frustum and cylinder at the push rod support end enables the push rod support end to withstand greater impact and friction forces, improving the reliability and stability of the push rod.

[0018] 3. The ejector pin component adopts a segmented design, which has good versatility. By replacing the ejector pin contact end and ejector pin support end with different shapes and sizes, it can be applied to the hot forging production of various shaft parts of different specifications, improving production efficiency and reducing production costs. After 1000 ejection cycles on a 1600T hot forging press, there was no deformation at the ejector pin contact end and ejector pin support end. Attached Figure Description

[0019] Figure 1 This is a perspective view of the present utility model;

[0020] Figure 2 This is a partial perspective view of the present invention;

[0021] Figure 3 This is a perspective view of the contact end and support end of the push rod of this utility model.

[0022] The markings in the diagram are: 1. Upper mold part; 11. Upper mold core; 12. Upper template; 13. Upper mold sleeve; 2. Lower mold part; 21. Lower mold core; 22. Lower mold sleeve; 23. First lower mold pad; 24. Second lower mold pad; 25. Upper fixing plate; 3. Ejector rod element; 31. Ejector rod contact end; 32. Ejector rod support end; 311. Circular through hole; 312. Limiting step; 321. Frustum; 322. Cylinder; 4. Workpiece; 5. Upper fixing plate; 6. Lower fixing plate. Detailed Implementation

[0023] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings:

[0024] like Figures 1 to 2 As shown, a segmented ejector pin suitable for hot forging pulley shaft molds includes an upper mold portion 1 and a lower mold portion 2. The entire mold structure is in a closed state.

[0025] The upper mold part 1 includes an upper mold core 11, an upper template 12, and an upper mold sleeve 13. The shape of the concave surface inside the upper mold core 11 is the same as the top shape of the workpiece 4. The upper mold sleeve 13 is fitted onto the side wall of the upper mold core 11, and the upper template 12 is fitted onto the side wall of the upper mold sleeve 13. The upper template 12 is connected to the upper fixed plate 5 of the injection molding machine.

[0026] The lower mold portion 2 includes a lower mold core 21, a lower mold sleeve 22, a first lower mold pad 23, and a second lower mold pad 24. The shape of the concave surface inside the lower mold core 21 is the same as the shape of the middle and bottom of the workpiece 4. The bottom of the lower mold core 21 is provided with a first lower mold pad 23 and a second lower mold pad 24 for raising it. The lower mold sleeve 22 is fitted onto the side walls of the lower mold core 21, the first lower mold pad 23, and the second lower mold pad 24. The lower mold template 25 is fitted onto the side walls of the lower mold sleeve 22. The lower mold template 25 is connected to the lower fixed plate 6 of the injection molding machine.

[0027] The movable plate of the injection molded part is connected to the lower fixed plate 6. During the sliding process, the movable plate of the injection molded part can drive the entire lower mold part 2 to disengage from the upper mold part 1, thereby completing the mold opening operation.

[0028] The upper mold core 11 and lower mold core 21 directly contact the high-temperature metal blank, responsible for the precise shaping of the workpiece's top contour, and must withstand temperatures ranging from 800 to 1200 degrees Celsius. The main function of the upper mold sleeve 13 and lower mold sleeve 22 is to clamp and secure them. They are used to fix and protect components such as the first lower mold pad 23, the second lower mold pad 24, the upper mold core 11, and the lower mold core 21, ensuring stable operation of the mold under high temperature and high pressure.

[0029] The lower die part 2 is provided with an ejector element 3 for ejecting the workpiece 4. The top of the ejector element 3 is in contact with the workpiece 4, and the bottom of the ejector element 3 is used to bear the pressure generated during hot forging. The top and bottom of the ejector element 3 are designed to be detachable.

[0030] Please refer to Figure 2 and Figure 3 As shown, the push rod element 3 includes a push rod contact end 31 and a push rod support end 32. The push rod contact end 31 has a circular through hole 311 in the middle and a limiting step 312 on the side wall surface of the push rod contact end 31. The circular through hole 311 of the push rod contact end 31 is sleeved on the top of the push rod support end 32.

[0031] The bottom of the top rod support end 32 is shaped like a frustum 321, and a cylinder 322 extends upward from the frustum 321. The frustum 321 and the cylinder 322 are designed as a single unit. The circular through hole 311 of the top rod contact end 31 is adapted to the top of the cylinder 322.

[0032] The material of the ejector pin contact end 31 is DH13 (Oberduwa hot work die steel), which has a hardness of 52-56 HRC (Rockwell hardness). The surface of the ejector pin contact end 31 also needs to be nitrided to increase its wear resistance.

[0033] The ejector pin support end 32 is made of hot work die steel. The cylinder 322 on the ejector pin support end 32 is a cylindrical shape with a bevel, and the top dimension of the ejector pin support end 32 matches the dimension of the circular through hole 311. The length of the ejector pin support end 32 is designed according to the length of the part. The design of the frustum 321 on the ejector pin support end 32 can reduce the instantaneous pressure generated during hot forging.

[0034] Regarding the installation positions of the ejector rod contact end 31 and the ejector rod support end 32: the bottom of the ejector rod support end 32 is attached to the surface of the first lower mold pad 23, the bottom of the ejector rod contact end 31 is attached to the surface of the second lower mold pad 24, and the top of the ejector rod support end 32 passes through the through hole at the top of the second lower mold pad 24 until it is inserted into the circular through hole 311 in the middle of the ejector rod contact end 31.

[0035] The bottom of the push rod support end 32 is attached to the surface of the first lower mold pad 23, the bottom of the push rod contact end 31 is attached to the surface of the second lower mold pad 24, and the top of the push rod support end 32 passes through the through hole at the top of the second lower mold pad 24 until it is inserted into the circular through hole 311 in the middle of the push rod contact end 31.

[0036] After this installation, the entire surface of the push rod contact end 31 fits with the bottom of the workpiece 4. Considering the thermal expansion and contraction of the workpiece 4, the size of the bottom of the workpiece 4 is 0.04 mm smaller than the size of the surface of the push rod contact end 31.

[0037] During the hot forging process, the ejector pin contact end 31 is the first to bear the force on the workpiece 4 compared to the ejector pin support end 32. Subsequently, the ejector pin support end 32 also needs to bear the force, and the ejector pin support end 32 can bear and disperse the pressure.

[0038] Working principle and usage of this utility model:

[0039] During the installation of the hot forging die, firstly, based on the dimensions of the workpiece 4 and the forging process requirements, a suitable length and diameter of the ejector pin support end 32 is selected and placed at the center of the second lower die pad 24. Then, the first lower die pad 23 is placed on the second lower die pad 24. Next, the ejector pin contact end 31 is connected to the ejector pin support end 32 through the circular through hole 311. Finally, the assembled ejector pin element 3 is installed in the corresponding position on the die. During the hot forging process, if the ejector pin contact end 31 is worn or damaged, it can simply be removed from the top of the ejector pin support end 32 and replaced with a new one, without needing to replace the entire ejector pin element 3, greatly reducing maintenance costs and replacement workload. Similarly, if the frustum 321 of the ejector pin support end 32 has a problem, it can also be replaced separately. This achieves the goal of improving production efficiency and reducing production costs.

[0040] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or adopt similar methods to replace them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A segmented ejector pin suitable for hot swaging wheel shaft die comprising an upper die portion (1) and a lower die portion (2), characterized in that, The lower die part (2) is provided with a push rod element (3) for ejecting the workpiece (4). The top of the push rod element (3) is in contact with the workpiece (4). The bottom of the push rod element (3) is used to bear the pressure generated during hot forging. The top and bottom of the push rod element (3) are designed to be detachable.

2. The segmented ejector rod suitable for hot swaging wheel shaft die as claimed in claim 1 wherein, The push rod element (3) includes a push rod contact end (31) and a push rod support end (32). The push rod contact end (31) has a circular through hole (311) in the middle and a limiting step (312) on the side wall surface of the push rod contact end (31). The circular through hole (311) of the push rod contact end (31) is sleeved on the top of the push rod support end (32).

3. The segmented ejector rod suitable for use in a hot swage wheel axle die according to claim 2, wherein, The bottom of the top rod support end (32) is shaped like a frustum (321), and a cylinder (322) extends upward from the frustum (321). The frustum (321) and the cylinder (322) are designed as a single unit. The circular through hole (311) of the top rod contact end (31) is adapted to the top of the cylinder (322).

4. The segmented ejector rod suitable for use in a hot swage wheel axle die according to claim 3, wherein, The upper mold part (1) includes an upper mold core (11), an upper template (12) and an upper mold sleeve (13). The shape of the concave surface inside the upper mold core (11) is the same as the top shape of the workpiece (4). The upper mold sleeve (13) is fitted on the side wall of the upper mold core (11), and the upper template (12) is fitted on the side wall of the upper mold sleeve (13).

5. The segmented ejector rod suitable for use in a hot swage wheel axle die according to claim 4, wherein, The lower mold part (2) includes a lower mold core (21), a lower mold sleeve (22), a first lower mold pad (23), and a second lower mold pad (24). The shape of the concave surface inside the lower mold core (21) is the same as the shape of the middle and bottom of the workpiece (4). The bottom of the lower mold core (21) is provided with a first lower mold pad (23) and a second lower mold pad (24) for raising. The side walls of the lower mold core (21), the first lower mold pad (23), and the second lower mold pad (24) are fitted with the lower mold sleeve (22). The side walls of the lower mold sleeve (22) are fitted with the lower template (25).

6. The segmented ejector rod suitable for use in a hot swage wheel axle die according to claim 5, wherein, The upper template (12) is connected to the upper fixed plate (5) of the injection molding machine, and the lower template (25) is connected to the lower fixed plate (6) of the injection molding machine.

7. The segmented ejector rod suitable for use in a hot swage wheel axle die according to claim 6, wherein, The bottom of the push rod support end (32) is attached to the surface of the first lower mold pad (23), the bottom of the push rod contact end (31) is attached to the surface of the second lower mold pad (24), and the top of the push rod support end (32) passes through the through hole at the top of the second lower mold pad (24) until it is inserted into the interior of the circular through hole (311) in the middle of the push rod contact end (31).

8. The segmented ejector rod suitable for use in a hot swage wheel axle die according to claim 7, wherein, The second lower mold pad (24) has an internal clearance groove adapted to the frustum (321), the height of which is greater than the height of the frustum (321), and the push rod support end (32) can slide up and down inside the second lower mold pad (24).

9. The segmented ejector rod suitable for hot swaging wheel shaft die of claim 3, wherein, The material of the push rod contact end (31) is Oberduwa hot work die steel, and the material of the push rod support end (32) is hot work die steel.

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