Middle die structure for transmission fluted disc forming die
By adopting a coaxial design between the forming block and the mold core in the gear disc forming mold, and optimizing the ejector pin hole and the clearance pin hole, the problems of easy cracking and low bonding strength during the first punch when the density is increased are solved, and the accurate forming and stable demolding of the high-density gear disc are achieved.
Patent Information
- Application Number
- CN202423295339.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2034-12-30
AI Technical Summary
In existing technologies, when producing transmission gear discs with a density higher than 6.9 g/cm3, the next punch is prone to cracking, and cracks are easily generated at the junction of the tooth profile and the disc surface, resulting in low product bonding strength and easy breakage.
The design employs a middle mold structure, utilizing a forming block to replace the next punch. The forming cavity and the mold core hole are coaxially arranged. Combined with the design of ejector pin holes and relief column holes, it ensures uniform material filling and uniform distribution of demolding force, avoiding stress concentration.
It increases product density, reduces cracks at the junction of the tooth profile and the disc surface, enhances product bonding strength, and prevents the tooth profile and disc surface from breaking.
Smart Images
Figure CN223733858U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of gear disc manufacturing technology, and more specifically, to a middle mold structure for a transmission gear disc forming mold. Background Technology
[0002] In existing technologies, for production such as Figure 1 When dealing with transmission gear discs where the tooth outer diameter is relatively small and the disc surface outer diameter is relatively large, a two-part die structure (upper-lower-lower-two-part) is used. The disc surface is formed by the lower D-die pressing under pressure. Specifically, it will be as follows... Figure 2 As shown, powder is filled into the straight tube B of the middle mold A. After the powder is filled, the driving device drives the upper punch C to move downward, so that the upper end of the lower punch D and the mold core E enter the straight tube B. Under the combined action of the upper punch C, the lower punch D and the mold core E, the powder in the straight tube B is extruded and shaped.
[0003] However, existing mold structures can only produce products with a density ≤6.9g / cm³. 3 If the density of the product is increased, it is prone to cracking in the next punch. In addition, due to the large demolding force at the joint between the tooth and the disc, cracks are easily generated, resulting in low product bonding strength and easy breakage and separation of the tooth and the disc. Summary of the Invention
[0004] The purpose of this application is to provide a middle mold structure for a transmission gear disc forming mold, which can solve the technical problems raised in the background art.
[0005] This application provides a middle mold structure for a transmission gear disc forming mold, including a middle mold body, an upward-opening receiving cavity on the middle mold body, a matching forming block inside the receiving cavity, a forming cavity penetrating the forming block, and a mold core hole at the bottom of the middle mold body communicating with the receiving cavity, the mold core hole and the forming cavity being on the same axis.
[0006] Furthermore, the forming cavity includes a disc-shaped cavity and a toothed cavity, with the disc-shaped cavity located at the top of the toothed cavity.
[0007] Furthermore, the bottom of the middle mold body is provided with a plurality of ejector pin holes that communicate with the receiving cavity, and the molding block is provided with a plurality of mold release holes that communicate with the disc-shaped cavity, and the mold release holes correspond one-to-one with the ejector pin holes.
[0008] Furthermore, the plurality of ejector pin holes are evenly arranged around the mold core hole.
[0009] Furthermore, the bottom of the middle mold body is provided with a plurality of first relief post holes that communicate with the receiving cavity, and the molding block is provided with a plurality of second relief post holes that communicate with the disc-shaped cavity, with the first relief post holes and the second relief post holes corresponding one to one.
[0010] Furthermore, a plurality of first relief post holes are evenly arranged around the mold core hole, and the first relief post holes are offset from the ejector pin holes.
[0011] The beneficial effects of this utility model are:
[0012] Compared with the prior art, this utility model directly forms transmission gear disc parts under pressure within the forming cavity of the forming block, replacing the previous punch in the prior art with the forming block. This effectively solves the problem of easy cracking of the previous punch under pressure when increasing product density. Since the forming cavity and the mold core hole are on the same axis, and the forming block is compatible with the receiving cavity, it can ensure the precise forming of the gear disc. During the forming process, the material can be evenly filled into all corners of the forming cavity, including the junction of the tooth shape and the disc surface, making the internal structure of the gear disc more compact and reducing internal stress concentration caused by uneven forming. This effectively solves the problem of cracks at the junction of the tooth shape and the disc surface caused by excessive local stress during demolding, ensuring the bonding strength of the product and preventing the tooth shape and the disc surface from breaking and separating. Attached Figure Description
[0013] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0014] Figure 1 This is a transmission gear disc type part with a relatively small tooth profile outer diameter and a relatively large disc surface outer diameter, which is currently the most advanced technology.
[0015] Figure 2 A schematic diagram of a mold structure for producing transmission gear disc-type parts in the prior art;
[0016] Figure 3 These are schematic diagrams of structures in some embodiments of this application;
[0017] Figure 4 These are cross-sectional views of some embodiments of this application;
[0018] Figure 5 Here are bottom views of some embodiments of this application;
[0019] The reference numerals in the attached figures are as follows:
[0020] A. Middle mold; B. Straight tube; C. Upper punch; D. Lower punch; E. Mold core; 1. Middle mold body; 2. Receiving cavity; 3. Forming block; 4. Forming cavity; 41. Disc-shaped cavity; 42. Toothed cavity; 5. Mold core hole; 6. Ejector pin hole; 7. Ejection hole; 8. First relief post hole; 9. Second relief post hole. Detailed Implementation
[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0022] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0024] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application 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, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0025] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0026] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Specific implementation examples:
[0028] like Figure 3 and Figure 4 As shown, this application provides a middle mold structure for a transmission gear disc forming mold, including a middle mold body 1. The middle mold body 1 has an upward-opening receiving cavity 2, and a matching forming block 3 is provided in the receiving cavity 2. A forming cavity 4 is provided through the forming block 3. The bottom of the middle mold body 1 has a mold core hole 5 communicating with the receiving cavity 2. The mold core hole 5 and the forming cavity 4 are on the same axis. Compared with the prior art, transmission gear disc parts are directly formed by pressure within the forming cavity 4 of the forming block 3. The forming block 3 replaces the next punch in the prior art, effectively solving the problem of lifting... The product density is prone to cracking under pressure during the current punching process. Since the forming cavity 4 and the mold core hole 5 are on the same axis, and the forming block 3 is adapted to the receiving cavity 2, it can ensure the precise forming of the toothed disc. During the forming process, the material can be evenly filled into all corners of the forming cavity 4, including the junction of the tooth shape and the disc surface, making the internal structure of the toothed disc more compact and reducing the internal stress concentration caused by uneven forming. This effectively solves the problem of cracks caused by excessive local stress during demolding, ensuring the bonding strength of the product and preventing the tooth shape and disc surface from breaking and separating.
[0029] like Figure 3 and Figure 4 As shown, the molding cavity 4 includes a disc-shaped cavity 41 and a toothed cavity 42. The disc-shaped cavity 41 is located at the top of the toothed cavity 42, which is conducive to better material fusion between the toothed cavity and the disc surface during the molding process. When the material fills the disc-shaped cavity 41 and then flows into the toothed cavity 42, there will be continuous material flow at the junction of the two, making the transition between the toothed cavity and the disc surface more natural and continuous. This can reduce the problem of low bonding strength caused by delamination or loose bonding, and improve the anti-separation ability of the toothed cavity and the disc surface during use.
[0030] like Figure 3-5 As shown, the bottom of the middle mold body 1 is provided with multiple ejector pin holes 6 that are connected to the receiving cavity 2, and the molding block 3 is provided with multiple demolding holes 7 that are connected to the disc-shaped cavity 41. The demolding holes 7 correspond one-to-one with the ejector pin holes 6, so that during the demolding process, the ejector pins can act on the molded gear disc through the ejector pin holes 6 and the demolding holes 7, making the demolding of the molded gear disc simple.
[0031] like Figure 3-5 As shown, multiple ejector pin holes 6 are evenly arranged around the mold core hole 5. In this embodiment, there are three ejector pin holes 6 to ensure that the force is uniform when the ejector pins act on the molded toothed disc through the ejector pin holes 6 and the mold release hole 7. This effectively avoids the deformation or damage of the toothed disc caused by the demolding force being concentrated at a certain point or in a certain area. Especially in areas where problems are prone to occur, such as the junction of the tooth shape and the disc surface, uniform demolding force helps to prevent cracks from forming.
[0032] like Figure 3-5 As shown, the bottom of the middle mold body 1 is provided with multiple first relief column holes 8 that communicate with the receiving cavity 2, and the molding block 3 is provided with multiple second relief column holes 9 that communicate with the disc cavity 41. The first relief column holes 8 and the second relief column holes 9 correspond one-to-one. In the production process of some gear disks, it is necessary to reserve mounting holes on the gear disk. The relief column is inserted into the first relief column hole 8 and the second relief column hole 9 and extends into the disc cavity 41, and the top of the relief column is flush with the top of the disc cavity 41. This allows the mounting hole to be formed on the molded gear disk by removing the relief column after the gear disk is extruded and formed. When producing gear disks that do not require mounting holes, the relief column is inserted into the first relief column hole 8 and the second relief column hole 9 and is flush with the top of the disc cavity 41. Production can be selected according to actual needs, which expands the practicality of the entire device.
[0033] like Figure 3-5 As shown, multiple first clearance post holes 8 are evenly arranged around the core hole 5. The first clearance post holes 8 are staggered with the ejector pin holes 6. In this embodiment, there are three first clearance post holes 8. Because the first clearance post holes 8 are staggered with the ejector pin holes 6, the demolding force applied by the ejector pin and the supporting force provided by the positioning post (when the mounting hole is reserved on the gear disk, the positioning post will also provide a certain supporting force) will not interfere with each other during the demolding process. If the ejector pin hole 6 and the clearance post hole are coincident or too close, it may cause local stress concentration in the molded gear disk during demolding. The staggered arrangement can make the stress on the molded gear disk more reasonable and reduce the risk of damage to the molded gear disk due to stress concentration.
[0034] Working principle:
[0035] In use, it is used in conjunction with ejector pins, mold cores, relief pins, and upper punches. Specifically, the middle mold structure of this application is fixed on the worktable and located below the upper punch. The mold core is inserted into the mold core hole 5, and the forming end of the mold core extends into the tooth cavity 42. The relief pins are inserted into the first relief pin hole 8 and the second relief pin hole 9. The upper end of the relief pin is adjusted to be at the top or bottom of the disk cavity 41 according to the needs of the gear disk to be produced. Powder is filled into the forming cavity 4. After the powder is filled, the upper punch moves downward. Under the combined action of the upper punch and the mold core, the powder in the forming cavity 4 is squeezed and formed. When demolding, the upper punch moves upward, the mold core and relief pins move downward, and the ejector pin moves upward to eject the formed gear disk.
[0036] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A middle mold structure for a transmission gear disc forming mold, characterized in that: The middle die body is provided with an upward opening containing cavity, and a matched forming block is arranged in the containing cavity.
2. A middle die structure for a forming die for a drive sprocket according to claim 1, characterized in that: The forming cavity comprises a disc-shaped cavity and a tooth-shaped cavity, and the disc-shaped cavity is located on the top of the tooth-shaped cavity.
3. A middle die structure for a forming die for a drive sprocket according to claim 2, characterized in that: The bottom of the middle die body is provided with a plurality of top pin holes in communication with the containing cavity, and the forming block is provided with a plurality of ejection holes in communication with the disc-shaped cavity, and the ejection holes correspond to the top pin holes one by one.
4. The middle die structure for a forming die of a driving sprocket according to claim 3, characterized in that: The plurality of top pin holes are uniformly arranged around the core hole.
5. A middle die structure for a forming die for a drive sprocket according to claim 4, characterized in that: The bottom of the middle die body is provided with a plurality of first clearance column holes in communication with the containing cavity, and the forming block is provided with a plurality of second clearance column holes in communication with the disc-shaped cavity, and the first clearance column holes correspond to the second clearance column holes one by one.
6. A middle die structure for a forming die for a drive sprocket according to claim 5, characterized in that: The plurality of first clearance column holes are uniformly arranged around the core hole, and the first clearance column holes are arranged in a staggered manner with the top pin holes.