Trimming die for high-stability motorcycle balance shaft

Abstract

The utility model discloses a trimming die for a high-stability motorcycle balance shaft. The trimming die comprises a base; a positioning lower cavity is formed in the top surface of the supporting lower die; the composite upper die comprises an upper trimming die, an upper pressing die and an elastic piece, a peripheral outer edge cutting edge is arranged on the bottom surface of the upper trimming die, and the upper pressing die is connected with the upper trimming die in a sliding manner; the output end of the lifting assembly is connected with the upper trimming die, the lifting assembly, the elastic piece and the upper pressing die are matched with one another to press the blank placed on the lower positioning cavity, and the lifting assembly is matched with the upper trimming die to cut off flashes of the blank. According to the high-stability trimming die for the motorcycle balance shaft, during trimming, the upper pressing die presses a blank on the lower supporting die through the elastic piece, the situation that the blank pries and influences the trimming quality is avoided, the upper pressing die and the upper trimming die are in relative sliding connection, and on the basis that the height position of the upper pressing die is kept unchanged, the trimming quality is improved. And the upper trimming die can continue to move downwards to cut the blank flash, so that indentations are prevented from being formed on the upper surface of the blank, and the trimming quality is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of balance shaft trimming technology, and in particular to a trimming mold for a high-stability motorcycle balance shaft. Background Technology

[0002] The working principle of a motorcycle balance shaft is based on the reverse vibration force generated by an eccentric block, which reduces vibration, balances the engine's operating state, improves driving comfort, and extends the engine's service life.

[0003] In the production of motorcycle balance shafts, forging, trimming, and shaping are typically required. Trimming dies are needed to remove the flash from the forged blank. Existing technology, such as Chinese utility model patent CN217647403U, discloses an eccentric shaft trimming die. This die features anti-warping protrusions on the cavity wall of the concentric block's upper chamber. During trimming, these protrusions press down on the blank, preventing the smaller outer diameter concentric block portion from warping upwards. This ensures the straightness of the product after trimming, improving the trimming quality of the eccentric shaft and preventing defective products.

[0004] Although the aforementioned trimming die can press the blank onto the lower die using the anti-warping protrusion, the anti-warping protrusion is fixed to the cavity wall of the punch and is relatively fixed to the cutting edge of the punch. This causes the anti-warping protrusion and the cutting edge to move synchronously during trimming. While the cutting edge removes the flash, the anti-warping protrusion also acts on the upper part of the blank, forming an indentation on the upper surface of the blank, which affects the final product molding quality.

[0005] Therefore, it is necessary to improve the existing cutting molds for motorcycle balance shafts. Utility Model Content

[0006] The purpose of this invention is to overcome the defects in the existing technology and provide a high-stability cutting mold for motorcycle balance shafts that avoids indentation, improves the cutting quality, and thus improves the final product molding quality.

[0007] To achieve the above technical effects, the technical solution of this utility model is: a cutting die for a high-stability motorcycle balance shaft, comprising:

[0008] Base;

[0009] A lower support mold is fixed above the base, and a positioning cavity is formed on the top surface of the lower support mold.

[0010] The composite upper mold is located directly above the supporting lower mold. The composite upper mold includes a cutting upper mold, a pressing upper mold, and an elastic element. The circumferential outer edge of the bottom surface of the cutting upper mold is a cutting edge for removing the flash of the blank. The projection of the cutting edge on the horizontal plane is located inside the projection of the positioning lower cavity opening on the horizontal plane, and the two are in clearance fit. The pressing upper mold is slidably connected to the cutting upper mold in the vertical direction through the elastic element.

[0011] A lifting assembly is provided on the base and its output end is connected to the upper cutting die. The lifting assembly, the elastic element and the upper pressing die cooperate with each other to press the blank placed on the lower positioning cavity. The lifting assembly cooperates with the upper cutting die to remove the flash of the blank.

[0012] Preferably, in order to ensure the clamping effect, the clamping upper die is located inside the cutting blade.

[0013] Preferably, in order to ensure the clamping effect and reduce the pressure on the top of the blank during clamping, the bottom surface of the clamping upper die is a clamping positioning bottom surface, and the clamping positioning bottom surface is adapted to the outer surface of the balance shaft.

[0014] Preferably, in order to ensure the positioning effect of the blank, the bottom surface of the upper cutting die is the cutting positioning bottom surface, and the cutting positioning bottom surface is adapted to the outer surface of the balance shaft.

[0015] Preferably, in order to reduce the pressure on the blank and further prevent indentation, at least two upper clamping dies are provided, which are spaced apart along the length of the lower positioning cavity.

[0016] Preferably, in order to ensure that each pressing die can act on the upper part of the blank, the number of pressing dies and elastic elements are equal and correspond one-to-one.

[0017] Preferably, in order to press the blank onto the supporting lower die by the upper clamping die during edge trimming, the elastic element includes a spring, a threaded sleeve, and a fixing frame. The fixing frame is fixed above the upper edge trimming die, the threaded sleeve is threadedly connected to the fixing frame, the top end of the spring is connected to the threaded sleeve, and the bottom end is located below the threaded sleeve and directly above the upper edge trimming die. The axis of the threaded sleeve and the axis of the spring both extend in the vertical direction.

[0018] Preferably, in order to protect the spring, the top of the threaded sleeve is closed, and the elastic element also includes a lower sleeve with an open top and a closed bottom. The outer circumferential edge of the lower sleeve is sealed to the inner circumferential wall of the threaded sleeve, and the bottom end of the spring is connected to the inner bottom wall of the lower sleeve.

[0019] Preferably, in order to facilitate the disassembly and maintenance of the upper cutting mold, the output end of the lifting assembly is detachably connected to the upper cutting mold.

[0020] Preferably, in order to achieve quick disassembly and connection, the output end of the lifting assembly is connected to the upper cutting mold via threaded bolts and nuts.

[0021] In summary, compared with the prior art, the cutting die for the high-stability motorcycle balance shaft of this utility model uses an elastic element to press the blank onto the supporting lower die during cutting, preventing the blank from being pried and affecting the cutting quality. The pressing upper die and the cutting upper die are relatively slidably connected, which allows the cutting upper die to continue to move downward to remove the blank flash while keeping the pressing upper die at a constant height position, avoiding the formation of indentations on the upper surface of the blank and ensuring the cutting quality. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of this utility model;

[0023] Figure 2 yes Figure 1 An explosion diagram;

[0024] Figure 3 This is an exploded structural diagram of the lifting component of this utility model;

[0025] Figure 4 This is a schematic diagram of the composite upper mold of this utility model;

[0026] Figure 5 This is a structural schematic diagram of the composite upper mold of this utility model from another perspective;

[0027] Figure 6 yes Figure 4 An explosion diagram;

[0028] Figure 7 This is a partial structural diagram of the supporting lower mold and the composite upper mold of this utility model;

[0029] Figure 8 yes Figure 7 Top view;

[0030] In the diagram: 1. Base; 2. Supporting lower mold; 21. Positioning lower cavity; 3. Trimming upper mold; 31. Cutting blade; 32. Trimming positioning bottom surface; 33. Connecting column; 34. Connecting plate; 35. Through hole; 4. Pressing upper mold; 41. Pressing positioning bottom surface; 42. Limiting plate; 5. Elastic element; 51. Spring; 52. Threaded sleeve; 53. Fixing frame; 54. Lower sleeve; 6. Lifting assembly; 61. Support column; 62. Top frame; 63. Hydraulic cylinder; 64. Lifting plate; 65. Guide rod; 66. Guide sleeve; 7. Bolt; 8. Nut. Detailed Implementation

[0031] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0032] like Figures 1-8 As shown, the present invention provides a cutting die for a high-stability motorcycle balance shaft, comprising:

[0033] Base 1;

[0034] The lower support mold 2 is fixed above the base 1, and the top surface of the lower support mold 2 is provided with a positioning lower cavity 21;

[0035] The composite upper mold is located directly above the supporting lower mold 2. The composite upper mold includes a cutting upper mold 3, a pressing upper mold 4, and an elastic element 5. The circumferential outer edge of the bottom surface of the cutting upper mold 3 is a cutting blade 31 used to remove the flash of the blank. The projection of the cutting blade 31 on the horizontal plane is located inside the projection of the cavity opening of the positioning lower cavity 21 on the horizontal plane, and the two are in clearance fit. The pressing upper mold 4 is slidably connected to the cutting upper mold 3 in the vertical direction through the elastic element 5.

[0036] Lifting component 6 is mounted on base 1 and its output end is connected to the cutting edge upper mold 3. Lifting component 6, elastic element 5 and pressing upper mold 4 cooperate with each other to press the blank placed on the positioning lower cavity 21. Lifting component 6 cooperates with cutting edge upper mold 3 to remove the flash of the blank.

[0037] When using this trimming die, the forged blank to be trimmed is placed on the lower support die 2. The lower support die 21 positions the blank, and the top surface of the lower support die 2 contacts the bottom surface of the blank's flash, thereby supporting the blank.

[0038] Then, the lifting assembly 6 moves, causing the trimming upper die 3 and the pressing upper die 4 in the composite upper die to move downwards simultaneously. The pressing upper die 4 first contacts the blank, pressing the blank onto the supporting lower die 2 to prevent the blank from being pried during trimming and affecting the trimming accuracy. After the pressing upper die 4 contacts the upper part of the blank, the lifting assembly 6 continues to drive the trimming upper die 3 downwards. The position of the pressing upper die 4 is fixed and unchanged by the elastic element 5. The trimming upper die 3 moves downwards relative to the pressing upper die 4, while increasing the pressing force of the pressing upper die 4 on the blank, until the cutting edge 31 of the trimming upper die 3 acts on the flash of the blank to cut off the flash. Then, the lifting assembly 6 drives the composite upper die upwards to facilitate the removal of the trimmed blank.

[0039] Compared with the prior art, the pressing upper die 4 in this utility model presses the blank onto the supporting lower die 2 while maintaining a relatively sliding connection with the trimming upper die 3 through the elastic element 5. This allows the trimming upper die 3 to continue moving downwards after the pressing upper die 4 contacts the upper part of the blank and the pressing upper die 4 is fixed in position. This allows the cutting edge 31 of the trimming upper die 3 to act on the flash of the blank while the blank is fixed, thus trimming the blank and avoiding the formation of indentations on the upper surface of the blank. This ensures the quality of the trimming and is beneficial to improving the quality of the product after subsequent processing.

[0040] A further improvement is that the upper clamping die 4 is located inside the cutting edge 31.

[0041] Specifically, the upper cutting die 3 is provided with a through hole 35 extending in the vertical direction. The outer circumferential edge of the upper pressing die 4 is sealed and fitted with the inner circumferential wall of the through hole 35, ensuring that the upper pressing die 4 can achieve a stable sliding fit with the upper cutting die 3 through the through hole 35. With the above design, the upper pressing die 4 can act on the inner side above the flash on the upper part of the blank, ensuring the pressing effect on the blank.

[0042] A further improvement is that the bottom surface of the upper clamping mold 4 is a clamping and positioning bottom surface 41, which is adapted to the outer surface of the balance shaft.

[0043] By adopting this design, the pressing and positioning bottom surface 41 of the pressing upper die 4 contacts the upper part of the blank, which can also achieve the positioning effect of the blank. At the same time, it increases the contact area with the blank, reduces the pressure on the blank, further avoids the formation of indentations on the blank, and improves the accuracy of flash removal.

[0044] A further improvement is that the bottom surface of the upper die 3 is the cutting edge positioning bottom surface 32, which is adapted to the outer surface of the balance shaft.

[0045] With the above design, when the flash is removed, the cutting edge positioning bottom surface 32 and the pressing positioning bottom surface 41 cooperate with each other and act on the upper half of the blank. While positioning the blank, the upper half of the blank can also be preliminarily shaped by the matching cutting edge positioning bottom surface 32 and pressing positioning bottom surface 41, thereby improving the accuracy of the final motorcycle balance shaft product.

[0046] A further improvement is that at least two upper clamping molds 4 are provided, which are spaced apart along the length of the lower positioning cavity 21.

[0047] Specifically, there are three upper clamping dies 4. The above design increases the contact area of ​​the blank when clamping it, thereby reducing the pressure on the blank and further avoiding indentations during the clamping process, thus ensuring the quality of the final product.

[0048] A further improvement is that the number of clamping upper molds 4 and elastic elements 5 are equal and correspond one-to-one.

[0049] By setting an equal number of elastic elements 5 as the upper clamping die 4, it can be ensured that each elastic element 5 acts on the upper clamping die 4, so that when cutting the edge, each upper clamping die 4 can act on the upper part of the blank and clamp the blank.

[0050] A further improvement is that the elastic element 5 includes a spring 51, a threaded sleeve 52, and a fixing frame 53. The fixing frame 53 is fixed above the upper cutting die 3. The threaded sleeve 52 is threadedly connected to the fixing frame 53. The top end of the spring 51 is connected to the threaded sleeve 52, and the bottom end is located below the threaded sleeve 52 and directly above the upper cutting die 3. The axis of the threaded sleeve 52 and the axis of the spring 51 both extend in the vertical direction. The top of the threaded sleeve 52 is closed. The elastic element 5 also includes a lower sleeve 54 that is open at the top and closed at the bottom. The outer circumferential edge of the lower sleeve 54 is sealed to the inner circumferential wall of the threaded sleeve 52. The bottom end of the spring 51 is connected to the inner bottom wall of the lower sleeve 54.

[0051] Specifically, the fixing frame 53 is inverted U-shaped and fixed above the upper cutting mold 3. A horizontal limiting plate 42 is fixed above the upper pressing mold 4. The limiting plate 42 is slidably sleeved on both ends of the fixing frame 53. A screw tube is provided on the top of the fixing frame 53. The inner wall of the screw tube is threadedly connected to the inner wall of the threaded sleeve 52. The two ends of the spring 51 are respectively connected to the top of the threaded sleeve 52 and the bottom of the lower sleeve 54 and are located in the enclosed cavity formed by the threaded sleeve 52 and the lower sleeve 54.

[0052] With the above design, the threaded sleeve 52 and the lower sleeve 54 surround the protective spring 51. When the lifting assembly 6 moves the composite upper die downward, the pressing and positioning bottom surface 41 of the pressing upper die 4 contacts the upper part of the blank, and the position of the pressing upper die 4 remains fixed. As the lifting assembly 6 continues to operate, the cutting upper die 3 continues to move downward, driving the fixing frame 53 to move downward. As the lower sleeve 54 abuts against the limiting plate 42, the spring 51 is compressed as the descent continues to increase. This allows the pressing upper die 4 to apply a pressing force to the blank when the cutting edge 31 contacts the flash of the blank, ensuring the pressing and positioning effect of the blank and thus ensuring the final cutting accuracy of the blank. The threaded sleeve 52 and the threaded tube are connected by threads, which makes it easy to adjust the height of the threaded sleeve 52 relative to the cutting upper die 3, thereby adjusting the pressing force on the blank before cutting and avoiding excessive or insufficient pressing force of the pressing upper die 4 on the blank.

[0053] A further improvement is that the output end of the lifting component 6 is detachably connected to the upper cutting die 3. This detachable connection facilitates the removal of the upper cutting die 3, allowing for the grinding of the cutting edge 31 and other maintenance operations. It also facilitates the replacement of the upper cutting die 3, extending its service life and ensuring the cutting effect.

[0054] A further improvement is that the output end of the lifting assembly 6 is connected to the upper cutting die 3 via threaded bolts 7 and nuts 8. This facilitates a quick and detachable connection between the output end of the lifting assembly 6 and the upper cutting die 3.

[0055] Specifically, the top of the upper mold 3 for cutting edge is provided with connecting columns 33 distributed along the length direction of the lower positioning cavity 21 and extending in the vertical direction. The top of the connecting columns 33 is fixed with a connecting plate 34 extending in the horizontal direction perpendicular to the length direction of the lower positioning cavity 21. The lifting assembly 6 includes pillars 61 fixed at the four corners of the base 1. The top of the pillars 61 is fixed with a horizontal top frame 62. The top frame 62 is integrally formed with a guide sleeve 66 extending in the vertical direction. The lifting assembly 6 includes a hydraulic cylinder 63. The cylinder of the hydraulic cylinder 63 is vertically downward and fixed above the top frame 62. A horizontal lifting plate 64 is fixed at the bottom of the piston rod. A guide rod 65 extending vertically and slidingly engaging with the guide sleeve 66 is also fixed above the lifting plate 64 to ensure that the lifting plate 64 can move stably in the vertical direction after the hydraulic cylinder 63 is activated. The four corners of the lifting plate 64 are connected to the ends of the two connecting plates 34 by four pairs of threaded bolts 7 and nuts 8. In this way, the output end of the lifting assembly 6 can be conveniently and detachably connected to the upper cutting mold 3.

[0056] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A cutting die for a high-stability motorcycle balance shaft, characterized in that, include: Base (1); The lower support mold (2) is fixed above the base (1), and the top surface of the lower support mold (2) is provided with a positioning lower cavity (21). The composite upper mold is located directly above the supporting lower mold (2). The composite upper mold includes a cutting upper mold (3), a pressing upper mold (4), and an elastic element (5). The circumferential outer edge of the bottom surface of the cutting upper mold (3) is a cutting blade (31) for cutting off the flash of the blank. The projection of the cutting blade (31) on the horizontal plane is located inside the projection of the cavity opening of the positioning lower cavity (21) on the horizontal plane, and the two are in clearance fit. The pressing upper mold (4) is slidably connected to the cutting upper mold (3) in the vertical direction through the elastic element (5). Lifting assembly (6), the lifting assembly (6) is disposed on the base (1) and its output end is connected to the cutting edge upper mold (3). The lifting assembly (6), the elastic element (5) and the pressing upper mold (4) cooperate with each other to press the blank placed on the positioning lower cavity (21). The lifting assembly (6) cooperates with the cutting edge upper mold (3) to remove the flash of the blank.

2. The cutting die for a high-stability motorcycle balance shaft according to claim 1, characterized in that: The upper clamping die (4) is located inside the cutting blade (31).

3. The cutting die for a high-stability motorcycle balance shaft according to claim 2, characterized in that: The bottom surface of the upper pressing mold (4) is the pressing positioning bottom surface (41), which is adapted to the outer surface of the balance shaft.

4. The cutting die for a high-stability motorcycle balance shaft according to claim 3, characterized in that: The bottom surface of the upper cutting mold (3) is the cutting positioning bottom surface (32), which is adapted to the outer surface of the balance shaft.

5. The cutting die for a high-stability motorcycle balance shaft according to claim 4, characterized in that: At least two upper clamping molds (4) are provided, which are spaced apart along the length of the lower positioning cavity (21).

6. The cutting die for a high-stability motorcycle balance shaft according to claim 5, characterized in that: The number of the pressing upper mold (4) and the number of the elastic elements (5) are equal and correspond one-to-one.

7. The cutting die for a high-stability motorcycle balance shaft according to any one of claims 1-6, characterized in that: The elastic element (5) includes a spring (51), a threaded sleeve (52), and a fixing frame (53). The fixing frame (53) is fixed above the upper cutting die (3). The threaded sleeve (52) is threadedly connected to the fixing frame (53). The top end of the spring (51) is connected to the threaded sleeve (52), and the bottom end is located below the threaded sleeve (52) and directly above the upper cutting die (3). The axis of the threaded sleeve (52) and the axis of the spring (51) both extend in the vertical direction.

8. The cutting die for a high-stability motorcycle balance shaft according to claim 7, characterized in that: The top of the threaded sleeve (52) is closed, and the elastic element (5) also includes a lower sleeve (54) with an open top and a closed bottom. The outer circumferential edge of the lower sleeve (54) is sealed to the inner circumferential wall of the threaded sleeve (52), and the bottom end of the spring (51) is connected to the inner bottom wall of the lower sleeve (54).

9. The cutting die for a high-stability motorcycle balance shaft according to any one of claims 1-6, characterized in that: The output end of the lifting component (6) is detachably connected to the upper cutting mold (3).

10. The cutting die for a high-stability motorcycle balance shaft according to claim 9, characterized in that: The output end of the lifting assembly (6) is connected to the upper cutting mold (3) via a threaded bolt (7) and nut (8).

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