Powder metallurgy helical tooth die convenient to reset

Abstract

The utility model discloses a powder metallurgy helical tooth die convenient to reset, which comprises a die holder, a forming cavity is arranged on the die holder, and a plurality of first helical tooth forming parts are arranged on the inner wall of the forming cavity; the upper punching assembly comprises an upper punching seat and an upper punching die, the upper punching die is provided with a mounting end and a forming end, the mounting end is rotatably mounted on the upper punching seat, and the forming end is provided with a second helical tooth forming part; the mounting end is provided with a first limiting part, the upper punching seat is provided with a second limiting part, an elastic piece is arranged between the first limiting part and the second limiting part, and the elastic piece is used for providing elastic stress for driving the first limiting part to be close to the second limiting part. According to the utility model, the first limiting part of the upper punching die and the second limiting part on the upper punching seat can be driven to be propped against each other in an initial state through elastic stress provided by the elastic piece, so that the initial positions of the upper punching die entering the forming cavity of the die seat are kept consistent when the upper punching die is formed every time.

Description

Technical Field

[0001] This utility model relates to the field of powder metallurgy technology, and in particular to a powder metallurgy helical tooth mold that is easy to reset. Background Technology

[0002] Existing powder metallurgy is a process technology that produces metal powder or uses metal powder as raw material, and then shapes and sinters to manufacture metal materials, composite materials and various types of products. Therefore, during manufacturing, the material powder is first filled between the molds, then compacted and heated through the molds, and finally the finished product is obtained.

[0003] In the process of forming helical gears using powder metallurgy molds, the upper punch is an inclined upper punch, and the middle die is a helical gear middle die. After the upper punch is guided out of the middle die by the inclination of the middle die, it often collidees with the middle die when it enters the middle die for the next time. This causes damage to both the upper punch and the middle die, and also endangers the safety of the operators. Utility Model Content

[0004] In order to overcome at least one of the defects of the prior art, the present invention provides a powder metallurgy helical tooth mold that is easy to reset. It can use an elastic element to provide elastic stress to drive the first limiting part of the upper punch and the second limiting part on the upper punch seat to remain abutting in the initial state, so that the initial position of the upper punch entering the forming cavity of the mold seat remains consistent each time it is formed.

[0005] The technical solution adopted by this utility model to solve its problem is:

[0006] A powder metallurgy helical gear mold that is easy to reset includes,

[0007] A mold base, wherein a forming cavity is provided on the mold base, and the inner wall of the forming cavity is provided with a plurality of first oblique tooth forming parts;

[0008] An upper punch assembly includes an upper punch base and an upper punch die. The upper punch die has a mounting end and a forming end. The mounting end is rotatably mounted on the upper punch base, and the forming end has a second oblique tooth forming part. The upper punch base can move upward or downward. When moving downward, the upper punch base is used to drive the forming end into the forming cavity so that the second oblique tooth forming part matches the first oblique tooth forming part. The mounting end is used to rotate to link the forming end when subjected to external force.

[0009] The mounting end is provided with a first limiting part, the upper punch is provided with a second limiting part, and an elastic element is provided between the first limiting part and the second limiting part. The elastic element is used to provide an elastic stress that drives the first limiting part to approach the second limiting part.

[0010] Furthermore, the upper punch seat is provided with a rotating cavity, and the mounting end is rotatably mounted in the rotating cavity.

[0011] Furthermore, the mounting end is provided with a rotating rod, and the upper punch seat is provided with a limiting groove, the limiting groove extending along the circumference of the upper punch seat; the rotating rod is slidably connected to the limiting groove, and the elastic element is used to provide the elastic stress to drive the rotating rod to abut against the end wall of the limiting groove.

[0012] Furthermore, the rotating rod extends out of the limiting groove, and the upper punch seat is provided with a limiting rod, the limiting rod and the limiting groove being spaced apart in the circumferential direction of the upper punch seat; one end of the elastic element is connected to the limiting rod, and the other end of the elastic element is connected to the rotating rod.

[0013] Furthermore, the limiting rod is provided with a first through hole, the rotating rod is provided with a second through hole, one end of the elastic element is connected to the first through hole, and the other end of the elastic element is connected to the second through hole.

[0014] Furthermore, the inner diameter of the limiting groove gradually increases from the end near the rotating cavity to the end away from the rotating cavity.

[0015] Furthermore, the mounting end is rotatably engaged with the rotating cavity via a rotating assembly; the rotating assembly includes at least two rotating plates distributed axially in the rotating cavity, and both end faces of the rotating plates are provided with lubrication grooves, which are filled with lubricating oil.

[0016] Furthermore, the lubrication groove extends spirally around the center of the rotating plate toward the edge of the rotating plate.

[0017] Furthermore, the end of the lubrication groove is spaced apart from the edge of the rotating plate.

[0018] Furthermore, the outer periphery of the mounting end is provided with a protruding step; the rotating component is provided between one end of the protruding step and the bottom wall of the rotating cavity; the rotating component is provided at the other end of the protruding step.

[0019] In summary, this utility model has the following technical effects:

[0020] An elastic element is provided between the upper die and the upper punch seat. Before forming, the elastic element provides elastic stress to drive the first limiting part on the mounting end of the upper die to rotate close to the second limiting part. That is, under the action of elastic stress, the first limiting part and the second limiting part are limited and abutted. In this position, the second oblique tooth forming part on the forming end of the upper die and the first oblique tooth forming part of the forming cavity are matched accordingly. When forming, the forming end of the upper die will not collide with the die when it extends into the forming cavity. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of the powder metallurgy helical tooth mold of this utility model.

[0022] Figure 2 This is a schematic diagram of the overall structure of the powder metallurgy helical tooth mold of this utility model;

[0023] Figure 3 This is a schematic diagram of the powder metallurgy helical tooth mold from another perspective.

[0024] Figure 4 This is a cross-sectional view of the upper punch of this utility model;

[0025] Figure 5 This is a schematic diagram of the structure of the rotating plate of this utility model.

[0026] The meanings of the reference numerals in the attached drawings are as follows: 10, mold base; 11, forming cavity; 111, first helical tooth forming part; 20, upper punch; 21, limiting rod; 22, limiting groove; 23, rotating cavity; 30, upper punch; 31, mounting end; 32, forming end; 321, second helical tooth forming part; 33, rotating rod; 331, second through hole; 40, rotating plate; 41, lubrication groove; 50, limiting nut; 60, elastic element. Detailed Implementation

[0027] To better understand and implement this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings.

[0028] In the description of this utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do 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, they should not be construed as limitations on this utility model.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0030] See Figures 1-5This utility model discloses a powder metallurgy helical tooth mold that is easy to reset, including a mold base 10 and an upper punch assembly. A forming cavity 11 is provided on the mold base 10, and a plurality of first helical tooth forming parts 111 are provided on the inner wall of the forming cavity 11. The plurality of first helical tooth forming parts 111 are arranged in the circumferential direction of the forming cavity 11.

[0031] The aforementioned upper punch assembly includes an upper punch base 20 and an upper punch die 30. The upper punch die 30 is provided with an mounting end 31 and a forming end 32. In this embodiment, the mounting end 31 and the forming end 32 can be located at the top and bottom ends of the upper punch die 30. The mounting end 31 is rotatably mounted on the upper punch base 20, and a second oblique tooth forming part 321 is provided at the forming end 32.

[0032] The upper punch 20 can move upward or downward under the drive of the drive structure. After the upper punch 20 moves downward, it drives the forming end 32 to extend into the forming cavity 11 so that the second helical tooth forming part 321 matches the first helical tooth forming part 111. The mounting end 31 can rotate when subjected to external force to link the forming end 32.

[0033] Specifically, the mounting end 31 is provided with a first limiting part, the upper punch seat 20 is provided with a second limiting part, and an elastic member 60 is provided between the first limiting part and the second limiting part. The elastic member 60 can provide an elastic stress that drives the first limiting part to approach the second limiting part.

[0034] Based on the above structure, when using the convenient reset powder metallurgy helical tooth mold of this utility model, when forming helical teeth of powder metallurgy products, the upper punch 20 can be driven to move downward by the drive structure. The forming end 32 of the upper punch 30 connected to the upper punch 20 can then extend into the forming cavity 11. The second helical tooth forming part 321 on the forming end 32 and the first helical tooth forming part 111 on the peripheral wall of the forming cavity 11 can be matched to form a helical tooth forming interval. In this way, the powder material in the helical tooth forming interval can form helical tooth products during the pressing process of the upper punch 30 and the mold base 10.

[0035] After the helical tooth product is formed, the upper punch 20 is driven upward by the drive structure to perform the demolding action. However, since the formed product has a helical tooth structure, if the upper punch 20 is directly driven upward to achieve demolding, there will be interference between the second helical tooth forming part 321 and the helical teeth on the product. Therefore, it is necessary to rotate the mounting end 31 of the upper punch 30 when the upper punch 20 is demolded. This makes the forming end 32 of the upper punch 30 rotate relative to the upper punch 20, matching the rotation of the helical tooth structure for demolding, thus making the demolding process smooth.

[0036] Since the upper die 30 needs to be rotated to demold during demolding, but during molding, the second oblique tooth forming part 321 of the forming end 32 of the upper die 30 needs to correspond with the first oblique tooth forming part 111. If the upper die 30 is demolded by the oblique guide of the mold base 10, the two are prone to misalignment when it enters the mold base 10 for pressing again. This causes the second oblique tooth forming part 321 on the upper die 30 to collide with the first oblique tooth forming part 111 on the mold base 10, resulting in damage.

[0037] Therefore, in this embodiment, an elastic element 60 is provided between the upper die 30 and the upper punch seat 20. Before molding, the elastic element 60 provides elastic stress to drive the first limiting part on the mounting end 31 of the upper die 30 to rotate close to the second limiting part. That is, under the action of elastic stress, the first limiting part and the second limiting part are limited and abutted. At this position, the second oblique tooth forming part 321 on the forming end 32 of the upper die 30 and the first oblique tooth forming part 111 of the forming cavity 11 are matched accordingly. When molding is performed at this time, the forming end 32 of the upper die 30 will not cause a collision when it extends into the forming cavity 11.

[0038] After molding, the upper die 30 of the upper punch holder 20 rotates to demold. During rotation, the first limiting part of the upper die 30 pulls the elastic element 60 to extend, without affecting the rotation and demolding of the upper die 30. After demolding is completed, the elastic element 60 can be reset, pulling the first limiting part closer to the second limiting part. After the first limiting part and the second limiting part abut against each other, the second oblique tooth forming part 321 on the forming end 32 of the upper die 30 returns to the position corresponding to and matching the first oblique tooth forming part 111 of the forming cavity 11. This ensures that the position of the upper die 30 is consistent each time it enters the mold base 10, reducing the collision between the upper die 30 and the lower die and improving the service life of the mold.

[0039] It should be noted that the first oblique tooth forming part and the second oblique tooth forming part in the above-mentioned mold base forming cavity can both be formed by the combination of oblique tooth groove and protruding oblique tooth structure in the prior art. Adjacent oblique tooth structures are spaced apart to form oblique tooth grooves. During forming, the positions of the first oblique tooth forming part and the second oblique tooth forming part can be matched accordingly.

[0040] Furthermore, a rotating cavity 23 is provided in the upper punch seat 20, and the mounting end 31 is rotatably mounted in the rotating cavity 23. In this way, the upper punch 30 can be rotatably engaged with the rotating cavity 23 of the upper punch seat 20 through the mounting end 31. That is, the rotational movement of the mounting end 31 of the upper punch 30 is limited by the rotating cavity 23. When the elastic member 60 pulls the first limiting part of the upper punch 30 to reset, the inner peripheral wall of the rotating cavity 23 is used as the guide surface to realize the rotational reset and prevent lateral sway.

[0041] Furthermore, the mounting end 31 is provided with a rotating rod 33, and the upper punch seat 20 is provided with a limiting groove 22, which extends circumferentially along the upper punch seat 20; the rotating rod 33 is slidably connected to the limiting groove 22, and the elastic member 60 is used to provide elastic stress to drive the rotating rod 33 to abut against the end wall of the limiting groove 22.

[0042] Based on the above structure, the limiting groove 22 can be an arc groove, so that the rotating rod 33 on the mounting end 31 can slide within the limiting groove 22, guiding the rotation and demolding action of the upper punch 30. When the upper punch 30 returns to the next forming position, the rotating rod 33 can abut against the end wall of the limiting groove 22. Thus, under the action of the elastic element 60, the return position of the upper punch 30 can be limited by the abutment position of the rotating rod 33 against the end wall of the limiting groove 22, so that the position of entering the mold base 10 remains consistent each time.

[0043] Thus, the rotating rod 33 is formed as the first limiting part, and the end wall of the limiting groove 22 is formed as the second limiting part.

[0044] To facilitate the installation of the elastic element 60, a limiting rod 21 can be provided on the upper punch seat 20. When assembling the rotating rod 33, the rotating rod 33 extends out of the limiting groove 22. The upper punch seat 20 is provided with the limiting rod 21, and the limiting rod 21 and the limiting groove 22 are spaced apart in the circumferential direction of the upper punch seat 20. One end of the elastic element 60 is connected to the limiting rod 21, and the other end of the elastic element 60 is connected to the rotating rod 33. In this way, when the upper punch 30 rotates to demold, the fixed point of the elastic element 60 is the connection point with the limiting rod 21, and the rotating rod 33 of the upper punch 30 pulls the elastic element 60 to stretch. During the return, since the fixed point of the elastic element 60 is at the position of the limiting rod 21, it can pull the rotating rod 33 back to the end wall abutment position of the limiting groove 22 and maintain the abutment position. In this way, the limiting structure is stable.

[0045] It should also be noted that, in the case where the rotating rod extends out of the limiting groove, a limiting boss structure can be further fitted onto the rotating rod 33. This limiting boss structure can be formed by a limiting nut 40 screwed onto the outside of the rotating rod, or by a limiting plate structure fitted onto the outside of the rotating rod. In this way, after the rotating rod passes through and extends out of the limiting groove, in order to prevent the rotating rod from separating from the limiting groove radially, the limiting boss structure can limit the rotation in the radial direction to prevent the rotating rod from separating. The limiting nut also provides radial limit protection, facilitating threaded assembly after the rotating rod is installed into the limiting groove, making assembly and disassembly convenient.

[0046] Of course, if the elastic element 60 is not fixed by the limiting rod 21 outside the limiting groove 22, and one end of the elastic element 60 is connected to the end wall of the limiting groove 22 and the other end of the elastic element 60 is connected to the rotating rod 33, the elastic stress of the elastic element 60 can also drive the rotating rod 33 back to its original position. However, the position of the return depends on the elastic stress, which is prone to instability after long-term stretching. Therefore, the return position is prone to change after a period of use. Therefore, in this embodiment, the fixed connection point of the elastic element 60 is set outside the limiting groove 22 and fixedly connected by the limiting rod 21. The return position provided by the elastic stress of the elastic element 60 is always against the end wall of the limiting groove 22. In this way, even if the elastic stress becomes loose, the limited position is still stably limited by the end wall of the limiting groove 22, improving the consistency of the return position.

[0047] Alternatively, one end of the elastic element 60 can be connected to the end wall of the limiting groove 22, and a positioning boss or positioning groove can be provided on the inner wall of the limiting groove 22. The elastic stress provided by the elastic element 60 can pull the rotating part back to its original position each time to perform a limiting engagement with the positioning boss or positioning groove provided in the groove. This can also achieve a stable limiting engagement structure and improve the consistency of the return position of the upper punch 30.

[0048] More specifically, to facilitate the stable installation of the elastic element 60, a first through hole can be provided on the limiting rod 21, and a second through hole 331 can be provided on the corresponding rotating rod 33. One end of the elastic element 60 is inserted into the first through hole, and the other end of the elastic element 60 is inserted into the second through hole 331. Based on this structure, the elastic element 60 can be selected as a tension spring in the prior art. One end of the tension spring can be inserted into the first through hole, and the other end of the tension spring can be inserted into the second through hole 331, so that the tension spring is less likely to detach.

[0049] Furthermore, the inner diameter of the limiting groove 22 gradually increases from the end near the rotating cavity 23 to the end away from the rotating cavity 23, that is, the limiting groove 22 can be V-shaped. In this way, when the rotating rod 33 swings in the limiting groove 22, the bottom wall and the top wall of the limiting groove 22 are in contact with the V-shaped surface. When the rotating rod 33 contacts the top and bottom surfaces of the limiting groove 22, the contact surface is increased, which effectively reduces the wear during limiting and increases the service life of the mold.

[0050] In addition, it should be noted that a guide rod structure can also be directly set on the inner wall of the rotating cavity 23, and a guide groove can be set on the outer periphery of the mounting end 31 of the upper punch 30, so that the guide rod can slide in the guide groove, which can also achieve the limiting positioning.

[0051] Further, see Figure 1 as well as Figure 5The mounting end 31 is rotatably engaged with the rotating cavity 23 via a rotating assembly. Specifically, the rotating assembly includes at least two rotating plates 40 distributed axially in the rotating cavity 23. Both end faces of the rotating plates 40 are provided with lubrication grooves 41, which are filled with lubricating oil.

[0052] If two rotating plates 40 are provided, one end face of one rotating plate 40 contacts the mounting end 31 of the upper punch 30, the other end face of the rotating plate 40 contacts one end face of the other rotating plate 40, and the other end face of the other rotating plate 40 contacts the bottom wall or top wall of the rotating cavity 23. Since the lubrication groove 41 is filled with lubricating oil, the lubrication effect can be improved, so that the upper punch 30 rotates smoothly.

[0053] Of course, three or more rotating plates 40 can be provided, with the middle rotating plate 40 serving as the uppermost and lowermost rotating receiving parts. The uppermost and lowermost rotating plates 40 can contact the mounting end 31 of the upper punch 30 and the end wall of the rotating cavity 23 respectively to achieve rotation guidance and smooth rotation.

[0054] If two rotating plates 40 are provided, a needle roller bearing can be installed between two adjacent rotating plates 40. The needle roller bearing can effectively reduce the upward rotation friction resistance and ensure smooth rotation.

[0055] In addition, the aforementioned rotating component can also be directly selected as a ball bearing in the prior art, which can be used to bear the stamping force of the upper punch and guide the upper punch to rotate smoothly.

[0056] In this embodiment, the lubrication groove 41 extends spirally around the center of the rotating plate 40 toward the edge of the rotating plate 40. The threaded groove on the rotating plate 40 can form a threaded contact surface on the end face of the rotating plate 40. When it contacts the mounting end 31 of the upper punch 30, it can withstand the pressure during the die forming process, reduce the force on the upper punch 30, and thus improve the service life of the upper punch 30.

[0057] Further, see Figure 5 The end of the lubrication groove 41 is spaced apart from the edge of the rotating plate 40, that is, the end of the lubrication groove 41 is a blind end and does not extend to the edge of the rotating plate 40. This ensures that the lubrication groove 41 does not break on the rotating plate 40. During the rotation of the upper punch 30, the lubricating oil in the lubrication groove 41 will not be thrown out from the edge under the centrifugal force of the rotating plate 40. Therefore, the upper and lower lubrication state is maintained, which is beneficial to prevent the grease from drying out after being heated and improves the service life of the lubrication.

[0058] Furthermore, a protruding step is provided on the outer periphery of the mounting end 31; a rotating component is provided between one end of the protruding step and the bottom wall of the rotating cavity 23; and a rotating component is provided at the other end of the protruding step.

[0059] When the upper punch rotates within the rotating cavity, the lower part of the protruding step can rotate and engage with the bottom wall of the rotating cavity via a rotating assembly. The protruding step can press against the rotating assembly from above, allowing the rotating assembly to better bear the force of the upper punch. Alternatively, a pad or pressure cap structure can be installed at the top of the upper punch seat, allowing the upper part of the protruding step to rotate and engage with the top of the rotating cavity via the rotating assembly, further smoothing the rotation of the upper punch.

[0060] The technical means disclosed in this utility model are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications are also considered within the scope of protection of this utility model.

Claims

1. A powder metallurgy helical gear mold that is easy to reset, characterized in that, include, A mold base, wherein a forming cavity is provided on the mold base, and the inner wall of the forming cavity is provided with a plurality of first oblique tooth forming parts; An upper punch assembly includes an upper punch base and an upper punch die. The upper punch die has a mounting end and a forming end. The mounting end is rotatably mounted on the upper punch base, and the forming end has a second helical tooth forming part. The upper punch base can move upward or downward. When moving downward, the upper punch base is used to drive the forming end into the forming cavity so that the second helical tooth forming part matches the first helical tooth forming part. The mounting end is used to rotate to link the forming end when subjected to external force. The mounting end is provided with a first limiting part, the upper punch is provided with a second limiting part, and an elastic element is provided between the first limiting part and the second limiting part. The elastic element is used to provide an elastic stress that drives the first limiting part to approach the second limiting part.

2. The powder metallurgy helical gear mold with convenient repositioning according to claim 1, characterized in that, The upper punch seat is provided with a rotating cavity, and the mounting end is rotatably mounted in the rotating cavity.

3. The powder metallurgy helical gear mold with convenient repositioning according to claim 2, characterized in that, The mounting end is provided with a rotating rod, and the upper punch seat is provided with a limiting groove, which extends circumferentially along the upper punch seat; the rotating rod is slidably connected to the limiting groove, and the elastic element is used to provide the elastic stress to drive the rotating rod to abut against the end wall of the limiting groove.

4. The powder metallurgy helical gear mold with convenient reset according to claim 3, characterized in that, The rotating rod extends out of the limiting groove, and the upper punch seat is provided with a limiting rod. The limiting rod and the limiting groove are spaced apart in the circumferential direction of the upper punch seat. One end of the elastic element is connected to the limiting rod, and the other end of the elastic element is connected to the rotating rod.

5. The powder metallurgy helical gear mold with convenient repositioning according to claim 4, characterized in that, The limiting rod has a first through hole, the rotating rod has a second through hole, one end of the elastic element is inserted through the first through hole, and the other end of the elastic element is inserted through the second through hole.

6. The powder metallurgy helical gear mold with convenient reset according to claim 3, characterized in that, The inner diameter of the limiting groove gradually increases from the end near the rotating cavity to the end away from the rotating cavity.

7. The powder metallurgy helical gear mold with convenient reset according to any one of claims 2-6, characterized in that, The mounting end is rotatably engaged with the rotating cavity via a rotating assembly; the rotating assembly includes at least two rotating plates distributed axially in the rotating cavity, and both end faces of the rotating plates are provided with lubrication grooves, which are filled with lubricating oil.

8. The powder metallurgy helical gear mold with convenient repositioning according to claim 7, characterized in that, The lubrication groove extends spirally around the center of the rotating plate toward the edge of the rotating plate.

9. The powder metallurgy helical gear mold with convenient repositioning according to claim 8, characterized in that, The end of the lubrication groove is spaced apart from the edge of the rotating plate.

10. The powder metallurgy helical gear mold with convenient repositioning according to claim 7, characterized in that, The outer periphery of the mounting end is provided with a protruding step; the rotating component is provided between one end of the protruding step and the bottom wall of the rotating cavity; the rotating component is provided at the other end of the protruding step.

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