Tooth-shaped upsetting tool for locking teeth of driving nut
Through the tooling structure of the main die assembly and the die assembly, the problem of uneven stress in the anti-loosening teeth processing of the drive nut is solved, efficient processing of the anti-loosening teeth and the durability of the mold are achieved, and cracking and cost increase are avoided.
Patent Information
- Application Number
- CN202510692209.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-27
- Publication Date
- 2025-08-29
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
When processing the anti-loosening teeth of the drive nut, the existing mold tools have uneven stress, which leads to the problem of cracking at the anti-loosening teeth, and the cost of modifying the mold is high and affecting the layout of the production line.
The tooling structure of the main die assembly and the die assembly is adopted. Through the cooperation of the main die rod and the toothed punch rod, the driving nut with a cone surface is first upset, and then the anti-loosening teeth are processed on a single station to avoid excessive material deformation. Use the inner pad and die sleeve to adjust the upsetting force to ensure processing consistency and durability.
It effectively avoids cracking of anti-loose teeth during the upsetting process, reduces the cost of mold modification, improves the consistency and durability of processing, and simplifies the tooling structure.
Smart Images
Figure CN120551318A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of tooling for machining a drive nut die, and in particular to a tooling for upsetting the tooth profile of anti-loosening teeth of a drive nut. Background Art
[0002] Threaded blind rivets are commonly used for riveting in the aerospace field. Threaded blind rivets are usually equipped with a drive nut that cooperates with the core rod thread. The drive nut is provided with anti-loosening teeth on the side close to the rivet body. When the threaded blind rivet is installed, the drive nut cooperates with the rivet body, and the anti-loosening teeth play a role in preventing loosening, making the riveting more stable and reliable.
[0003] There are many existing methods for processing anti-loosening teeth of drive nuts, such as upsetting stamping, cutting, cold extrusion, laser tooth engraving or grinding, among which the upsetting process is a processing method that utilizes the plastic deformation of metal under the action of external force, and uses a mold to redistribute and transfer the metal volume, thereby forming the required parts. It has high efficiency, low cost, good tooth shape consistency, is suitable for mass production, and is widely used in the processing of anti-loosening teeth of nuts. The upsetting process usually uses a special mold to form on a cold upsetting machine or a punch press, and forms a tooth structure through upsetting deformation. For example, the patent with announcement number CN218611506U discloses a warm upsetting forming mold for processing hexagonal self-locking nuts, including an upper mold assembly and a lower mold assembly, and the upper mold assembly and the lower mold assembly are respectively assembled and connected with the corresponding upper and lower mold cavities of the warm upsetting machine; the upper mold assembly includes an upper mold sleeve, and an upper mold push rod extending out of the bottom surface of the upper mold sleeve is provided in the upper mold sleeve cavity. The longitudinal cross-section of the mold ejector pin is a T-shaped structure, and a section of the upper mold ejector pin extending out of the upper mold sleeve is a hexagonal body, and an upper mold ejector pin pad for axially limiting the upper mold ejector pin is also provided in the upper mold sleeve cavity; the lower mold assembly includes a lower mold sleeve, a mold core is installed in the lower mold sleeve cavity, and the bottom of the lower mold sleeve is detachably connected to a locking sleeve for locking the mold core position, the mold core includes a hexagonal mold piece installed in a preset hole in the top of the lower mold sleeve and a support body located at the bottom of the hexagonal mold piece, the hexagonal mold piece is provided with a hexagonal hole matching the nut, the support body is axially provided with a through hole coaxial with the hexagonal hole, the bottom end of the locking sleeve is provided with a hollow lower mold pad, the lower mold pad is sequentially provided with a lower mold ejector sleeve and a lower mold ejector pin pad from top to bottom, the lower mold ejector pin is installed in the lower mold ejector pin sleeve, the lower mold ejector pin extends into the through hole opened in the support body, and is used to press the hexagonal self-locking nut, and the bottom end of the lower mold pad is provided with a compression spring. The anti-loosening teeth of the self-locking nut in the above solution are set on the flange surface of the nut, and the nut body and the anti-loosening teeth can be completed in one go through a multi-station mold; Figure 1The figure shows a driving nut with anti-loosening teeth, which has a hexagonal shape and a conical surface on one side of the driving nut, and the anti-loosening teeth are distributed circumferentially on the conical surface. In order to achieve mass production, the existing mold is usually designed as a multi-station. If a conventional multi-station mold is used to complete the shape and anti-loosening teeth of the driving nut at one time, the material thickness at the conical surface is smaller than the nut body, the deformation amount is different but the pressure is the same, resulting in uneven force. During the upsetting process, the anti-loosening teeth of the nut are prone to excessive force and cracking. To avoid this phenomenon, a protrusion can be provided at the end of the mold core to cooperate with the inner hole of the nut to prevent the material from deforming and cracking toward the inner hole during upsetting. Such a mold core is not convenient for removing the upset nut. If a step-by-step processing method is adopted, a mold for upsetting the anti-loosening teeth can be added to the existing mold. Since the anti-loosening teeth are different from the common anti-loosening teeth structure located on the flange surface, the cost of modifying the mold will be greatly increased and will affect the layout of the entire production line. Summary of the Invention
[0004] In view of the shortcomings of the existing technology, the technical problem solved by the present invention is to provide a tool for upsetting the tooth shape of the anti-loosening teeth of the drive nut, so as to solve the problem of uneven force on the anti-loosening teeth of the drive nut processed by the existing mold tooling.
[0005] In order to solve the above problems, the technical solution adopted by the present invention is: a tool for upsetting the tooth profile of the anti-loosening teeth of the drive nut, comprising a main mold assembly and a punch assembly, wherein the main mold assembly comprises a main mold and a main mold rod, the main mold is provided with a first mounting hole penetrating along the horizontal direction, the first mounting hole is a hexagonal hole with chamfers at both ends, the drive nut to be processed can be placed in the first mounting hole, the main mold rod is a hexagonal prism, the main mold rod is slidably set in the first mounting hole on the main mold and abuts against the end face of the drive nut, the punch assembly comprises a toothed punch rod, the toothed punch is provided with a toothed groove, and the structure of the toothed groove corresponds to the anti-loosening teeth.
[0006] Furthermore, the die assembly also includes a die sleeve and an inner pad, and the toothed punch rod and the inner pad are slidably arranged in the die sleeve.
[0007] Furthermore, the length of the main mold rod is greater than the length of the main mold.
[0008] Furthermore, the die sleeve is provided with a second mounting hole in the horizontal direction, the second mounting hole is a stepped circular hole, the toothed die rod is a cylinder as a whole, the toothed die rod is slidably arranged in the second mounting hole, and a limiting frustum is provided at one end of the toothed die rod located in the larger section of the second mounting hole, and the inner pad is arranged in the larger section of the second mounting hole and abuts against the die sleeve.
[0009] Furthermore, the first mounting hole is clearance-matched with the driving nut and the main mold rod.
[0010] Furthermore, the diameter of the toothed punch is equal to the diameter of the inscribed circle of the hexagonal outer shape of the drive nut.
[0011] Furthermore, the toothed punch is provided with a chamfer at the connection between the end face of the toothed groove and the outer circular surface.
[0012] Furthermore, the diameter of the inner pad is two to three times the diameter of the toothed punch.
[0013] Furthermore, the die clearance between the toothed punch and the main die is 0.05 mm.
[0014] Compared with the existing technology, the beneficial effects of this solution are: 1. Compared with the existing mold that is completed by upsetting in one time, the tooling of the present invention can be used to upset the anti-loosening teeth on the conical surface of the drive nut. After using other molds to upset the drive nut with a conical surface, the material deformation is small when the tooling is used to process the anti-loosening teeth. The upsetting force for processing the anti-loosening teeth separately is relatively small. The two upsetting forces are different, which can effectively avoid cracking during the upsetting process. There is no need to set a protrusion on the main mold rod to match the inner hole of the drive nut, and the main mold rod can be used to push the processed drive nut out of the main mold. The tooling structure is simple, durable, and has good processing consistency. 2. The single-station structure is adopted. Compared with the multi-station mold tooling that processes multiple parts at the same time, it is necessary to consider the situation of each part when adjusting the upsetting force. The single-station tooling only targets one part, and its upsetting pressure is more convenient to adjust, effectively avoiding damage caused by excessive force on the drive nut. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 is a schematic diagram of the drive nut; Figure 2 It is a schematic diagram of the overall structure of the present invention; Figure 3 Schematic diagram of the main mold of the present invention; Figure 4 Schematic diagram of the main mold bar of the present invention; Figure 5 It is a schematic diagram of the die sleeve of the present invention; Figure 6 A schematic diagram of a toothed punch according to the present invention; In the figure: 1-driving nut, 2-main die, 3-main die rod, 4-die sleeve, 5-toothed punch rod, 6-inner pad, 51-toothed groove. DETAILED DESCRIPTION
[0016] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0017] Implementation example Figures 2 to 6 As shown: a tool for forging the tooth profile of a drive nut for anti-loosening, comprising a main die assembly and a punch assembly, wherein the main die assembly comprises a main die 2 and a main die rod 3, the main die 2 is provided with a first mounting hole penetrating in the horizontal direction, the first mounting hole is a hexagonal hole with chamfers at both ends, the drive nut 1 to be processed can be placed in the first mounting hole, the hexagonal hole can position the drive nut 1, and the chamfer is provided to facilitate the placement of the drive nut 1, the main die rod 3 is a hexagonal prism, the main die rod 3 is slidably set in the first mounting hole on the main die 2 and abuts against the end face of the drive nut 1, so as to facilitate the ejection of the processed drive nut 1, the first mounting hole and the drive nut 1 and the main die rod 3 are clearance-matched, and the clearance is 0.02mm to 0.05mm, the punch assembly comprises a die sleeve 4, a toothed punch rod 5 and an inner pad 6, the toothed punch rod 5 and the inner pad 6 are slidably set in the die sleeve 4, the toothed punch rod 5 is provided with a toothed groove 51, the structure of the toothed groove 51 is consistent with the anti-loosening tooth Correspondingly, during upsetting, the toothed groove 51 applies pressure to the conical surface on the drive nut 1 to deform the conical surface to form anti-loosening teeth. The die sleeve and the inner pad are universal components. When processing anti-loosening teeth of different specifications, the corresponding toothed punch rod can be replaced. The toothed punch rod 5 enters the first mounting hole for upsetting. The over-die clearance between the toothed punch rod 5 and the main die 2 is 0.05mm, which effectively ensures the coaxiality of the toothed punch rod 5 and the drive nut 1; the main die rod 3 provides support for the drive nut 1 during upsetting. The length of the main die rod 3 is greater than the length of the main die 2. After upsetting, the drive nut 1 can be pushed out of the main die 2; the die sleeve 4 is provided with a second mounting hole in the horizontal direction, and the second mounting hole is a stepped circular hole. The toothed die rod is a cylindrical body as a whole, and the toothed punch rod 5 is slidably arranged in the second mounting hole. A limiting cone is provided at one end of the toothed punch rod 5 located in the larger section of the second mounting hole, and the inner pad 6 is arranged in the larger section of the second mounting hole and abuts against the die sleeve 4.
[0018] The diameter of the toothed punch 5 is equal to the diameter of the inscribed circle of the hexagonal outer shape of the drive nut 1; the toothed punch 5 is provided with a chamfer at the connection between the end face and the outer cylindrical surface of the toothed punch 5. During upsetting, the contact surface between the toothed punch 5 and the drive nut 1 is only at the position of the conical surface, thereby avoiding deformation of the portion of the drive nut 1 close to the conical surface; the diameter of the inner pad 6 is two to three times the diameter of the toothed punch 5, and the inner pad 6 can slide in the die sleeve 4 to transmit the pressure of the cold upsetting equipment to the toothed punch 5 and limit the stroke of the toothed punch 5; The specific implementation process is as follows: Before processing the anti-loosening teeth, the drive nut 1 is formed into a drive nut 1 with a conical surface through the steps of blank, upsetting shape, and punching. At this time, it is a semi-finished product. When using the tooling, the main mold assembly is installed in the mold cavity of the main mold 2 seat of the cold heading equipment and locked and fixed. The die assembly is installed in the mold cavity of the die seat and locked and fixed. The main mold rod 3 and the toothed punch rod 5 are coaxial. A certain distance is reserved between the main mold 2 and the die to facilitate the placement of the drive nut 1. The drive nut 1 to be processed is placed in the first mounting hole of the main mold 2. The drive nut 1 A conical surface is provided on one side facing outward, and the driving nut 1 abuts against the end face of the main mold rod 3 away from the conical surface. The inner pad 6 pushes the toothed punch rod 5 to move toward the main mold 2. The toothed groove 51 of the toothed punch rod 5 applies pressure to the conical surface of the driving nut 1, causing the conical surface to deform to form anti-loosening teeth. The main mold rod 3 moves toward the direction of the die assembly to push out the driving nut 1, completing the processing of the anti-loosening teeth. After the anti-loosening teeth are processed, the nut is tapped and heat-treated to obtain the finished driving nut 1. The tooling structure is simple, the durability is strong, and the processing consistency is good.
[0019] The above is only an embodiment of the present invention, and the common knowledge such as the specific structure and characteristics of the scheme is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.
Claims
1. A tool for upsetting the tooth profile of a drive nut anti-loosening tooth, comprising a main die assembly and a punch die assembly, wherein the main die assembly comprises a main die and a main die bar, characterized in that: The main mold is provided with a first mounting hole passing through in the horizontal direction. The first mounting hole is a hexagonal hole with chamfers at both ends. The drive nut to be processed can be placed in the first mounting hole. The main mold rod is a hexagonal prism. The main mold rod is slidably set in the first mounting hole on the main mold and abuts against the end face of the drive nut. The die assembly includes a toothed punch rod, and a toothed groove is provided on the toothed punch. The structure of the toothed groove corresponds to the anti-loosening tooth.
2. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 1, characterized in that: The die assembly further comprises a die sleeve and an inner pad, and the toothed punch rod and the inner pad are slidably arranged in the die sleeve.
3. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 1, characterized in that: The length of the main mold rod is greater than the length of the main mold.
4. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 2, characterized in that: The die sleeve is provided with a second mounting hole in the horizontal direction, the second mounting hole is a stepped circular hole, the toothed die rod is a cylinder as a whole, the toothed die rod is slidably arranged in the second mounting hole, and a limiting frustum is provided at one end of the toothed die rod located in a larger section of the second mounting hole, and the inner pad is arranged in a larger section of the second mounting hole and abuts against the die sleeve.
5. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 1, characterized in that: The first mounting hole is clearance-matched with the driving nut and the main mold rod.
6. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 1, characterized in that: The diameter of the toothed punch is equal to the diameter of the inscribed circle of the hexagonal outer shape of the drive nut.
7. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 1, characterized in that: The toothed punch is provided with a chamfer at the connection between the end face of the toothed groove and the outer circular surface.
8. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 2, characterized in that: The diameter of the inner pad is two to three times the diameter of the toothed punch rod, and the inner pad can slide in the die sleeve.
9. The tool for upsetting the tooth profile of the anti-loosening teeth of a drive nut according to claim 1, characterized in that: The die clearance between the toothed punch and the main die is 0.05 mm.