High-quality bolt outer rod portion spline cold heading anti-deformation mechanism and method

Abstract

The application discloses a high-quality bolt outer rod portion flower tooth cold heading anti-deformation mechanism and method, relates to metal bolt processing technology field, including outer frame and bolt, still including the cold heading module of installation in the outer frame inside, the outer frame top is equipped with hydraulic rod, is used for driving cold heading module to carry out high pressure cold heading, the bottom of the outer frame inside is equipped with mechanical adjusting module. Advantages lie in: the application is aimed at the core problems such as the fixture gap leading to uneven clamping, one-time cold heading leading to metal flow disorder in the existing cold heading technology, and through the optimization of structure and process in many aspects, it has significant advantages, the wedge-shaped gathering clamping structure eliminates the fixture gap, improves positioning accuracy, the segmented cold heading design solves the problem of uneven metal flow, guarantees the quality of the flower tooth, the buffer limiting structure avoids bolt deformation, the pushing and liquid supplementing structure realizes the accurate expansion and contraction of the tooth, guarantees the smooth process, the overall structure has universality, stability and high efficiency, and is suitable for mass production.

Description

Technical Field

[0001] This invention relates to the field of metal bolt processing technology, and in particular to a high-quality bolt outer shank cold heading anti-deformation mechanism and method. Background Technology

[0002] Straight-knot bolts on the outer shank are commonly used for anti-loosening, torque transmission, or press-fit connections, requiring extremely high standards for tooth coaxiality, fullness, uniformity, and absence of defects. Currently, mass production mainly uses cold heading, which is efficient and provides good strength. However, existing cold heading dies and processes still have significant defects. The straight-knot clamps in cold heading dies often use a split-jaw structure, with unavoidable movement gaps between the jaws, sliders, and guide rails. Over time, these gaps will further increase, leading to inconsistent clamping forces, significant differences in the gripping force between the left and right jaws on the shank, and unstable workpiece positioning and centering. During cold heading, circumferential offset and axial movement are prone to occur, ultimately causing quality problems such as straight-knot tooth skew, misalignment, and uneven tooth pitch. Therefore, CN107866513B discloses a clamping device for a cold heading machine, which includes a frame, a mounting plate on the frame, and several sets of clamping clamp assemblies on the mounting plate. Each clamping clamp assembly includes a swing arm, a first clamping clamp, and a second clamping clamp. One end of the first clamping clamp is a first clamping end, and the other end is a first driving end. One end of the second clamping clamp is a second clamping end, and the other end is a second driving end. The first driving end and the second driving end respectively abut against the two side walls opposite to the swing arm. The rotation of the swing arm causes the first driving end and the second driving end on both sides to swing in opposite directions. The frame is also provided with a driving device for driving the swing arm to rotate and a first reset device for resetting the first clamping clamp and the second clamping clamp.

[0003] The clamping device of the aforementioned cold heading machine adopts a swing arm-driven double jaw synchronous swing clamping. The background technology clearly points out that traditional clamping devices have defects such as unstable clamping, asynchronous clamping, and large gaps, resulting in inaccurate workpiece positioning and poor machining accuracy. Although this patent improves the clamping synchronization to a certain extent, it does not fundamentally solve the problem of uneven clamping force and tooth offset caused by the gap of the clamp, nor does it address the problem of uneven metal flow and tooth incompleteness caused by one-time cold heading during tooth forming.

[0004] Therefore, a new type of high-quality bolt outer rod tooth cold forging anti-deformation mechanism can be adopted to solve the shortcomings of the existing technology. Summary of the Invention

[0005] The purpose of this invention is to solve the problems existing in the prior art, and to propose a high-quality bolt outer rod part serration cold forging anti-deformation mechanism and method.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A high-quality bolt outer rod part serration cold heading anti-deformation mechanism includes an outer frame and bolts, and also includes a cold heading module installed inside the outer frame; A hydraulic rod is installed on the top of the outer frame to drive the cold heading module to perform high-pressure cold heading. A mechanical adjustment module is installed at the bottom inside the outer frame to adjust the horizontal position of the cold heading module. The cold heading module includes a lower pressure plate, a support plate, and multiple sets of cold heading dies. The lower pressure plate is fixedly connected to the telescopic end of the hydraulic rod, and the support plate is connected to the mechanical adjustment module. The cold heading mold consists of a pressing component and a deformation component. The deformation component consists of a limiting cylinder, a wedge-shaped guide rail, and a chuck. The chuck consists of multiple sets of wedge-shaped push blocks. Each set of wedge-shaped push blocks is equipped with multiple pressing teeth for cold heading straight knives. A pushing mechanism is installed between each wedge-shaped push block and its corresponding pressing teeth.

[0007] Preferably, the pressing assembly includes a punch plate fixedly connected to the pressing plate, a disc fixedly mounted on the punch plate, and a pressing head mounted on the disc via a buffer mechanism, the bottom of the pressing head adopting a wedge-shaped concave design.

[0008] Preferably, the punch plate is rotatably mounted with multiple sets of rolling structures, each set of rolling structures consisting of multiple sets of rollers, which cooperate with the corresponding wedge-shaped push block.

[0009] Preferably, the buffer mechanism includes multiple limiting slide rods fixedly installed on the pressure head, each limiting slide rod being slidably connected to the disc, and multiple first springs being fixedly installed between the disc and the pressure head, each first spring being sleeved on the outside of the corresponding limiting slide rod.

[0010] Preferably, the pushing mechanism includes a vertical rail slidably mounted on the wedge-shaped push block, the pressure teeth are slidably connected to the vertical rail, a fixing plate is fixedly mounted on the wedge-shaped push block, the fixing plate has multiple storage slots, each storage slot has a hydraulic telescopic rod fixedly mounted in it, the telescopic end of each hydraulic telescopic rod is fixedly connected to the vertical rail, and two sets of fluid replenishment structures that cooperate with the multiple hydraulic telescopic rods are mounted on the wedge-shaped push block.

[0011] Preferably, the fluid replenishment structure includes a reservoir cylinder fixedly mounted on a wedge-shaped pusher block, a piston disc slidably mounted inside the reservoir cylinder, multiple second springs fixedly mounted between the piston disc and the bottom of the reservoir cylinder, a conduit connecting the reservoir cylinder and multiple hydraulic telescopic rods, a limiting block cooperating with the piston disc fixedly mounted inside the reservoir cylinder, two limiting frames fixedly mounted outside the reservoir cylinder, a vertical rod slidably mounted on each of the two limiting frames, a stop plate fixedly mounted at the upper end of the two vertical rods, and a sliding plate fixedly mounted at the bottom of the two vertical rods, the sliding plate being located inside the reservoir cylinder, multiple elastic telescopic rods fixedly mounted at the bottom of the sliding plate, each elastic telescopic rod having a fixed connection between its telescopic end and the piston disc, and a transmission mechanism installed between the disc and the stop plate.

[0012] Preferably, the transmission mechanism includes a movable ring slidably mounted on a disc, and the movable ring is equipped with multiple sets of pushing mechanisms that cooperate with corresponding abutments.

[0013] Preferably, the pushing mechanism includes a slide rail fixedly mounted on a movable ring, the slide rail being slidably connected to a disc, a push rod being slidably mounted on the slide rail, and a plurality of spring rods being fixedly mounted on the slide rail, with the telescopic end of each spring rod being fixedly connected to the push rod.

[0014] Preferably, each push rod has a plurality of ball bearings rolled on its bottom.

[0015] This invention also provides a method for preventing deformation during cold forging of the outer shank teeth of a high-quality bolt, comprising the aforementioned mechanism for preventing deformation during cold forging of the outer shank teeth of a high-quality bolt, and further comprising the following steps: S1. Workpiece positioning and placement: The semi-finished bolt is precisely placed on the positioning position of the wedge-shaped pusher to ensure that the bolt axis is coaxial with the convergence center of the wedge-shaped pusher. This ensures that the bolt is subjected to uniform force during the subsequent cold heading process, lays the foundation for the coaxiality of the tooth forming, and avoids the subsequent tooth offset caused by the initial positioning deviation. S2. Initially lock the limit, start the hydraulic rod, the hydraulic rod outputs driving force to drive the lower pressure plate to move vertically downward, the lower pressure plate synchronously drives the lower pressure assembly to move downward until the lower end face of the lower pressure assembly is tightly abutted against the top end face of the semi-finished bolt, to initially lock the bolt axially, restrict the axial movement of the bolt during the cold heading process, and prevent the axial displacement from affecting the forming accuracy of the tooth pattern. S3. Wedge-shaped clamping: Continue to apply continuous and stable pressure through the hydraulic rod, pushing the pressing component to move downward until the pressing component is in close contact with the top surface of the wedge-shaped push block and the pressure is transmitted; under the action of pressure, the wedge-shaped push block slides downward along the wedge-shaped guide rail. With the guidance of the wedge-shaped guide rail, the wedge-shaped push block synchronously converges towards the side closer to the bolt's central axis until the pressure teeth on the wedge-shaped push block initially contact the outer surface of the bolt, completing the radial clamping and positioning of the bolt and eliminating the clamping instability problem caused by the fixture clearance; S4. First segmented cold heading. Maintain continuous pressure on the hydraulic rod. After the pressure tooth contacts the outer part of the bolt, it is subjected to a reaction force and gradually retracts into the wedge-shaped push block until the pressure tooth reaches the preset first extension limit and can no longer retract. At this time, the pressure tooth part is pressed into the outer part of the bolt, initially extruding to form an incomplete straight knurled pattern. Since the pressure tooth does not fully extend out of the wedge-shaped push block at this time, the single flow range of the bolt metal molecules is small and the deformation is controllable, effectively avoiding the metal flow disorder caused by a single large deformation. S5. Second segmented cold forging. The hydraulic rod continues to apply pressure, driving the pressure teeth to fully extend from the wedge-shaped pusher, and performing a second extrusion deformation on the outer part of the bolt. Through segmented cold forging, the bolt metal molecules gradually flow and fully fill the tooth cavity, resulting in more uniform metal flow. This ultimately produces high-quality straight knurled teeth with full, flawless, and highly coaxial teeth, while reducing local stress concentration and improving the structural strength and forming consistency of the bolt knurled teeth.

[0016] Compared with existing technologies, the advantages of this invention are: 1. The deformation component in the cold heading module of this application consists of a limiting cylinder, a wedge-shaped guide rail, and a chuck. The chuck adopts a multi-set wedge-shaped push block splicing structure. With the continuous pressure of the hydraulic rod, the wedge-shaped push blocks move synchronously down along the wedge-shaped guide rail and converge towards the bolt's central axis. This eliminates the left-right split jaw design in the prior art, structurally eliminating the movement gap between the jaws and the slider and guide rail. At the same time, the close fit between the pressing component and the wedge-shaped push blocks transmits pressure, ensuring that the radial clamping force of the multiple sets of wedge-shaped push blocks on the bolt is uniform and consistent. This avoids the bolt's circumferential offset and axial movement problems caused by the difference in clamping force in the prior art, and provides a reliable guarantee for the coaxiality of the straight knurling forming.

[0017] 2. This application achieves two-stage cold forging of straight knives by coordinating the pushing mechanism and the pressure teeth. Unlike the one-time cold forging method in the prior art, during the first cold forging, the pressure teeth do not fully extend from the wedge-shaped push block. The single flow range of the bolt metal molecules is small and the deformation is controllable, avoiding the metal flow disorder caused by a single large deformation. During the second cold forging, the pressure teeth fully extend and perform secondary compression on the outer part of the bolt, so that the metal molecules gradually flow and fully fill the tooth cavity. This design effectively solves the problems of tooth tip defects, tooth root material shortages, and tooth surface peeling caused by uneven metal flow in the prior art. At the same time, it reduces local stress concentration, improves the structural strength and forming consistency of the bolt knives, and meets the high precision requirements of high-end fasteners for straight knives.

[0018] 3. The buffer mechanism in the pressing assembly consists of a limiting slide rod and a first spring. The limiting slide rod passes through the disc and the pressing head, and the first spring is sleeved on the outside of the limiting slide rod. When the pressing head abuts against the top of the bolt, the disc, which continues to move downward, will compress the first spring. The elastic buffering effect of the spring is used to avoid the bolt top from deforming due to excessive pressure. At the same time, the bottom of the pressing head adopts a wedge-shaped concave design, which matches the size of the bolt end after cold heading. This can not only achieve axial positioning of the bolt, but also prevent metal molecules from flowing upward and deforming during cold heading. Compared with the existing technology, which lacks buffering and precise positioning, this application effectively reduces the risk of bolt deformation and further improves the forming accuracy of the tooth pattern.

[0019] 4. The pushing mechanism consists of a vertical rail, a fixed plate, and a hydraulic telescopic rod. The fluid replenishment structure includes a reservoir, a piston disc, and an elastic telescopic rod. The hydraulic telescopic rod is connected to the pressing teeth via the vertical rail, and the reservoir is connected to the hydraulic telescopic rod via a conduit. During the first cold heading, the pressing teeth retract under the reaction force of the bolts, causing the hydraulic telescopic rod to contract. Hydraulic oil enters the reservoir and pushes the piston disc upward. During the second cold heading, the transmission mechanism drives the abutment plate downward, which pushes the piston disc downward through the vertical rod, sliding plate, and elastic telescopic rod, pressing the hydraulic oil back onto the hydraulic telescopic rod, thus fully extending the pressing teeth. This structural design achieves precise control of the pressing teeth's extension and retraction. Compared to the shortcomings of existing technologies where segmented cold heading makes it difficult to precisely control the deformation, the pushing and fluid replenishment structures of this application work together to ensure that the deformation of the two cold headings is controllable, improving the consistency of the tooth forming. At the same time, the buffering effect of the elastic telescopic rod makes the pressure transmission more stable, avoiding excessive local pressure that could damage the tooth profile.

[0020] 5. This application includes a mechanical adjustment module that can adjust the horizontal position of the cold heading module, facilitating the processing of bolts of different specifications and improving the versatility of the mechanism. The cold heading die adopts a multi-set design, enabling the simultaneous cold heading of multiple bolts, thus improving production efficiency. Simultaneously, the rollers on the punch plate cooperate with the wedge-shaped push blocks, reducing friction between them and ensuring smoother convergence of the wedge-shaped push blocks, preventing mechanism jamming due to excessive friction. Ball bearings are installed at the bottom of the push rod in the transmission mechanism, reducing wear between the push rod and the backing plate and extending the service life of the mechanism. Compared to the shortcomings of existing technologies, such as simple structure, poor versatility, and easy wear, the overall structure of this application balances adjustability, stability, and high efficiency, ensuring high-quality forming while meeting the needs of mass production and reducing production costs. Attached Figure Description

[0021] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the structure of a high-quality bolt outer rod part cold forging anti-deformation mechanism proposed in this invention; Figure 2 for Figure 1 Detailed schematic diagram of the frontal planar structure; Figure 3 for Figure 1 Detailed schematic diagram of the structure after removing the external frame; Figure 4 for Figure 3 Detailed schematic diagram of the enlarged structure of the intercooling heading module; Figure 5 for Figure 4 Detailed schematic diagram of the frontal planar structure; Figure 6 for Figure 5 Enlarged structural schematic diagram of the cold heading die; Figure 7 for Figure 6 Detailed diagram of the decomposed structure; Figure 8 for Figure 7 Detailed schematic diagram of the middle and lower pressure components after rotating at a certain angle and being magnified; Figure 9 for Figure 8 Detailed schematic diagram of the structure after removing the transmission mechanism; Figure 10 for Figure 8 Enlarged schematic diagram of the middle disc and transmission mechanism; Figure 11 for Figure 10 A detailed enlarged schematic diagram of one of the driving structures; Figure 12 for Figure 11 Enlarged schematic diagram of the end of the push rod; Figure 13 for Figure 7 Detailed schematic diagram of the combined structure of the center clamp, bolts, and wedge guide rail; Figure 14 for Figure 13 Detailed schematic diagram of the structure including the retained bolt and one of the wedge-shaped push blocks; Figure 15 for Figure 14 Detailed schematic diagram of the frontal planar structure; Figure 16 for Figure 14 Detailed schematic diagram of the structure after removing the bolts and cutting open the wedge-shaped pusher block; Figure 17 for Figure 16 Detailed schematic diagram of the structure after removing the wedge-shaped pusher and rotating it by a certain angle; Figure 18 for Figure 17 Detailed schematic diagram of the structure after the fixing plate and liquid storage cylinder 32 are cut open; Figure 19 for Figure 17 Detailed schematic diagram of the structure after rotation at a certain angle.

[0022] In the diagram: 1. Outer frame, 2. Hydraulic rod, 3. Cold heading module, 4. Mechanical adjustment module, 5. Lower pressure plate, 6. Support plate, 7. Cold heading mold, 8. Lower pressure assembly, 9. Deformation assembly, 10. Chuck, 11. Wedge guide rail, 12. Limiting cylinder, 13. Punch plate, 14. Roller, 15. Disc, 16. Press head, 17. Transmission mechanism, 18. Buffer mechanism, 19. First spring, 20. Limiting slide bar, 21. Moving ring, 22. Pushing structure, 23. Slide rail, 24. Push rod, 25. Spring rod, 26. Ball bearing, 27. Wedge push block, 28. Bolt, 29. Pressing teeth, 30. Vertical rail, 31. Fixing plate, 32. Liquid storage cylinder, 33. Limiting frame, 34. Vertical rod, 35. Support plate, 36. Hydraulic telescopic rod, 37. Slide plate, 38. Elastic telescopic rod, 39. Piston disc, 40. Second spring. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1: Refer to Figures 1-3 A high-quality bolt outer rod part serrated cold heading anti-deformation mechanism includes an outer frame 1 and bolts 28, and also includes a cold heading module 3 installed inside the outer frame 1; A hydraulic rod 2 is installed on the top of the outer frame 1 to drive the cold heading module 3 to perform high-pressure cold heading. A mechanical adjustment module 4 is installed at the bottom inside the outer frame 1 to adjust the horizontal position of the cold heading module 3.

[0025] The outer frame 1 serves as the load-bearing foundation of the entire mechanism, integrating the hydraulic rod 2, cold heading module 3, and mechanical adjustment module 4 into a whole. This ensures that each component remains relatively fixed during the high-pressure cold heading process, avoiding the impact of component displacement on processing accuracy. Its stable design provides a prerequisite for subsequent precise processing. Hydraulic rod 2 serves as the core power source, driving cold heading module 3 to complete the cold heading action. Compared with the drive structure with unstable power output in the existing technology, the design of hydraulic rod 2 can effectively avoid the problem of uneven tooth forming caused by pressure fluctuation. The mechanical adjustment module 4 is connected to the cold heading module 3. Through the adjustment function of the mechanical adjustment module 4, the horizontal position of the cold heading module 3 can be flexibly adjusted to adapt to the processing of bolts 28 with different diameters and lengths, thus solving the defects of the existing technology that have poor mechanism versatility and can only process bolts 28 of a single specification.

[0026] Example 2: This example differs from Example 1 in that: (Refer to...) Figures 1-19 The cold heading module 3 includes a lower pressure plate 5, a support plate 6, and multiple sets of cold heading molds 7. The lower pressure plate 5 is fixedly connected to the telescopic end of the hydraulic rod 2, and the support plate 6 is connected to the mechanical adjustment module 4. The cold heading die 7 consists of a pressing component 8 and a deformation component 9. The deformation component 9 consists of a limiting cylinder 12, a wedge-shaped guide rail 11, and a chuck 10. The chuck 10 consists of multiple sets of wedge-shaped push blocks 27. Each set of wedge-shaped push blocks 27 is equipped with multiple pressing teeth 29 for cold heading straight knives. A pushing mechanism is installed between each wedge-shaped push block 27 and the corresponding pressing tooth 29.

[0027] In the cold heading module 3, the lower pressure plate 5 is responsible for transmitting the power of the hydraulic rod 2, and the support plate 6 plays the role of supporting the cold heading mold 7. Multiple sets of cold heading molds 7 are arranged in parallel, which can realize the simultaneous cold heading of multiple bolts 28, greatly improving production efficiency and meeting the needs of mass production. The pressing component 8 and the deformation component 9 of the cold heading die 7 work together. The pressing component 8 is responsible for axially limiting the bolt 28, and the deformation component 9 is responsible for radial clamping and tooth forming. The limiting cylinder 12 limits the movement trajectory of the wedge-shaped push block 27 to prevent it from deviating. The wedge guide rail 11 utilizes the guiding characteristics of the wedge structure to make multiple sets of wedge push blocks 27 converge synchronously towards the central axis of the bolt 28 under pressure, ensuring uniform clamping force; The chuck 10 is composed of multiple sets of wedge-shaped push blocks 27, which work with the pressure teeth 29 to achieve the cold heading of the tooth pattern. The push mechanism controls the extension and retraction of the pressure teeth 29 to complete the segmented cold heading. The advantages of this modular design are that each component has a clear division of labor and is detachable, which facilitates installation, debugging and later maintenance. At the same time, the gathering method of the wedge push block 27 abandons the structure of the left and right split jaws in the existing technology, eliminates the gap between the jaws and the guide rail from the root, and solves the problems of uneven clamping force, circumferential displacement of bolt 28 and axial movement in the existing technology, which greatly improves the positioning accuracy and the quality of the tooth forming.

[0028] The pressing assembly 8 includes a punch plate 13 fixedly connected to the pressing plate 5. A disc 15 is fixedly installed on the punch plate 13. A pressing head 16 is installed on the disc 15 through a buffer mechanism 18. The bottom of the pressing head 16 adopts a wedge-shaped concave design (this design is to adapt to the inclined surface of the wedge-shaped push block 27). The lower pressure assembly 8 is the core component of the cold heading module 3 for pressure transmission and workpiece positioning. The various structures work together to complete axial positioning and pressure buffering. The punch plate 13 and the lower pressure plate 5 are rigidly fixedly connected to ensure that the driving force output by the hydraulic rod 2 can be completely and without loss transmitted to the punch plate 13, driving the punch plate 13 to move down synchronously. The punch plate 13 also serves as the mounting carrier of the disc 15, providing a stable mounting base for the subsequent buffer mechanism 18 and pressure head 16, and avoiding uneven pressure transmission due to loose installation. The disc 15 is fixed below the punch plate 13, serving as a connecting link. On the one hand, it provides a precise installation platform for the buffer mechanism 18, ensuring that the components of the buffer mechanism 18 can be precisely aligned and work together. On the other hand, it evenly distributes the high pressure transmitted by the punch plate 13 to the pressure head 16, preventing excessive local stress on the pressure head 16, which could lead to uneven stress and deformation at the top of the bolt 28. The pressure head 16 is flexibly connected to the disc 15 through the buffer mechanism 18. Its bottom wedge-shaped concave design is precisely sized to match the end size of the bolt 28 after cold heading. During operation, the pressure head 16 first abuts tightly against the top end face of the bolt 28 to achieve axial positioning of the bolt 28 and prevent the bolt 28 from moving upward during cold heading. At the same time, the wedge-shaped concave structure can effectively block the upward flow of metal molecules and avoid defects such as bulging and deformation at the top of the bolt 28. The advantage of this structural design is that it achieves stable pressure transmission and precise workpiece positioning. Compared with the shortcomings of existing technologies where the pressure head 16 is simple in design, mostly planar in structure, and has poor positioning effect, the wedge-shaped concave design of the pressure head 16 in this application has higher positioning accuracy. Combined with the buffer mechanism 18, it can effectively protect the top of the bolt 28 and reduce the workpiece damage rate. At the same time, the rigid connection design between the punch plate 13 and the disc 15 avoids power loss during the power transmission process, further improves the stability of the cold heading process, and provides a guarantee for the precision of the tooth forming.

[0029] Multiple sets of rolling structures are rotatably installed on the punch plate 13. Each set of rolling structures consists of multiple sets of rollers 14, which cooperate with the corresponding wedge-shaped push block 27. The rolling structure is a key auxiliary structure to ensure the smooth convergence of the wedge-shaped push block 27. It works in conjunction with the punch plate 13 and the wedge-shaped push block 27 to achieve a significant reduction in friction. Each set of rolling structures consists of multiple sets of rollers 14. The rollers 14 are rotatably installed below the punch plate 13 via a rotating shaft. Their installation position is precisely aligned with the top of the wedge-shaped push block 27 to ensure that when the punch plate 13 moves down, the rollers 14 can make precise contact with the top of the wedge-shaped push block 27 and cooperate in working. During operation, as the hydraulic rod 2 drives the punch plate 13 to move downward, after the pressure head 16 abuts against the top of the bolt 28 and completes the initial limiting, the punch plate 13 continues to move downward. At this time, the roller 14 contacts the top of the wedge-shaped push block 27. As the punch plate 13 continues to apply pressure, the roller 14 rotates under the reaction force of the wedge-shaped push block 27, converting the sliding friction between the punch plate 13 and the wedge-shaped push block 27 into rolling friction, which greatly reduces the frictional resistance between the two. The advantage of this structural design is that it effectively avoids problems such as jamming and asynchronous movement of the wedge pusher 27 due to excessive friction. It ensures that multiple sets of wedge pushers 27 can converge synchronously towards the central axis of the bolt 28 along the wedge guide rail 11, ensuring uniform clamping force. Compared with the defects of direct rigid contact and high friction between the punch plate 13 and the clamping components in the prior art, the rolling structure of this application, through the rotation of the roller 14, not only reduces friction loss and extends the service life of the punch plate 13 and the wedge pusher 27, but also improves the smoothness and synchronization of the convergence of the wedge pushers 27, further ensuring the positioning accuracy of the bolt 28 and avoiding quality problems such as tooth misalignment and non-concentricity caused by the poor movement of the wedge pushers 27.

[0030] The buffer mechanism 18 includes multiple limiting slide rods 20 fixedly installed on the pressure head 16. Each limiting slide rod 20 is slidably connected to the disc 15. Multiple first springs 19 are fixedly installed between the disc 15 and the pressure head 16. Each first spring 19 is sleeved on the outside of the corresponding limiting slide rod 20. The buffer mechanism 18 is the core structure that prevents deformation of the top of the bolt 28 and achieves stable pressure transmission. It is composed of the limiting slide rod 20 and the first spring 19. The components are closely matched and have clear division of labor. The limiting slide rod 20 is fixedly installed on the top of the pressure head 16 and is evenly distributed. Its upper end passes through the disc 15 and forms a sliding connection with the disc 15. It can provide precise guidance for the up and down movement of the pressure head 16 and limit the movement trajectory of the pressure head 16, preventing the pressure head 16 from deviating or tilting under pressure, and ensuring that the pressure head 16 is precisely fitted with the top of the bolt 28. The first spring 19 is sleeved outside the limiting slide bar 20, and its two ends are fixedly connected to the bottom of the disc 15 and the top of the pressure head 16 respectively. When it is in a natural extension and contraction state, it can support the pressure head 16 to maintain a stable position. During operation, when the pressure head 16 abuts against the top of the bolt 28, the punch plate 13 drives the disc 15 to continue moving downward. At this time, the pressure head 16 cannot continue to move downward due to the reaction force of the bolt 28, and the distance between the disc 15 and the pressure head 16 is reduced. The first spring 19 is compressed. By utilizing the elastic buffering effect of the spring, the instantaneous high pressure transmitted by the hydraulic rod 2 is converted into a stable pressure, avoiding the instantaneous excessive pressure that could cause the top of the bolt 28 to deform or the pressure head 16 to be damaged. The advantage of this structural design is that it achieves flexible pressure transmission, which can protect the workpiece and equipment components, and ensure uniform axial pressure of the pressure head 16 on the bolt 28. Compared with most cold heading devices in the prior art, which lack a buffer mechanism 18 and have direct and harsh pressure transmission, easily leading to workpiece deformation and rapid component wear, the buffer mechanism 18 of this application effectively solves the above problems through the guiding limit of the limiting slide rod 20 and the elastic buffer of the first spring 19, extending the service life of the equipment, and further improving the positioning stability of the bolt 28, providing a strong guarantee for the forming accuracy of the tooth pattern.

[0031] The pushing mechanism includes a vertical rail 30 that is slidably mounted on a wedge-shaped pusher 27. The pressure teeth 29 are slidably connected to the vertical rail 30. A fixing plate 31 is fixedly mounted on the wedge-shaped pusher 27. The fixing plate 31 has multiple storage slots. A hydraulic telescopic rod 36 is fixedly mounted in each storage slot. The telescopic end of each hydraulic telescopic rod 36 is fixedly connected to the vertical rail 30. Two sets of fluid replenishment structures that cooperate with the multiple hydraulic telescopic rods 36 are mounted on the wedge-shaped pusher 27. The pushing mechanism is the core actuator for achieving precise extension and retraction of the pressure tooth 29 and completing segmented cold heading. All structures work together to ensure that the extension and retraction stroke of the pressure tooth 29 is controllable and the movement is smooth. The vertical rail 30 is slidably installed in the reserved groove of the wedge-shaped push block 27 and can slide up and down along the groove. The pressure tooth 29 is slidably connected to the vertical rail 30 to ensure that the pressure tooth 29 can precisely extend and retract along the vertical rail 30. At the same time, the vertical rail 30 can compensate for the displacement when the wedge-shaped push block 27 moves down, so that the pressure tooth 29 always remains relatively stationary with the outer rod of the bolt 28, ensuring the forming accuracy of the tooth pattern. The fixing plate 31 is fixed on the wedge-shaped push block 27. The storage groove on it is used for precise installation of the hydraulic telescopic rod 36. It not only fixes and limits the hydraulic telescopic rod 36, but also protects the hydraulic telescopic rod 36 from damage by metal chips during the cold heading process, thus extending its service life. The hydraulic telescopic rod 36 serves as the power source for the extension and retraction of the pressure tooth 29. Its extension and retraction end is fixedly connected to the vertical rail 30. Through its own extension and retraction, it drives the vertical rail 30 to move, thereby driving the pressure tooth 29 to extend or retract the wedge-shaped push block 27. The two sets of fluid replenishment structures are connected to multiple hydraulic telescopic rods 36, providing stable hydraulic power support for the extension and retraction of the hydraulic telescopic rod 36, ensuring that the hydraulic telescopic rod 36 moves accurately and responds quickly. During operation, in the first cold forging stage, the pressure tooth 29 contacts the bolt 28 and is subjected to a reaction force, which drives the vertical rail 30 to move, thereby pushing the hydraulic telescopic rod 36 to retract, and the fluid replenishment structure simultaneously completes the fluid replenishment preparation; in the second cold forging stage, the fluid replenishment structure delivers hydraulic oil to the hydraulic telescopic rod 36, pushing the hydraulic telescopic rod 36 to extend, which drives the vertical rail 30 and the pressure tooth 29 to extend, completing the secondary extrusion; The advantage of this structural design is that it achieves precise control over the extension and retraction of the pressure tooth 29, ensuring controllable deformation during segmented cold heading. Simultaneously, the clear division of labor among components and their stable installation facilitate maintenance. Compared to the shortcomings of existing technologies where segmented cold heading suffers from difficulty in precisely controlling the extension and retraction stroke of the pressure tooth 29 and uneven deformation, the propulsion mechanism in this application, combined with the fluid replenishment structure, effectively ensures precise and controllable deformation during the two cold heading processes, improving the consistency of tooth forming and avoiding problems such as missing tooth tips and uneven tooth spacing.

[0032] The fluid replenishment structure includes a reservoir 32 fixedly mounted on a wedge-shaped pusher 27, a piston disc 39 slidably mounted inside the reservoir 32, multiple second springs 40 fixedly mounted on the piston disc 39 and the bottom of the reservoir 32, and conduits connecting the reservoir 32 and multiple hydraulic telescopic rods 36. A limiting block cooperating with the piston disc 39 is fixedly mounted inside the reservoir 32, and two limiting frames 33 are fixedly mounted on the outside of the reservoir 32. A vertical rod 34 is slidably mounted on each of the two limiting frames 33. A stop plate 35 is fixedly mounted on the upper end of the two vertical rods 34, and a sliding plate 37 is fixedly mounted on the bottom of the two vertical rods 34. The sliding plate 37 is located inside the reservoir 32, and multiple elastic telescopic rods 38 are fixedly mounted on the bottom of the sliding plate 37. The telescopic end of each elastic telescopic rod 38 is fixedly connected to the piston disc 39. A transmission mechanism 17 is installed between the disc 15 and the stop plate 35. The fluid replenishment structure provides the power for the driving mechanism. It works in conjunction with the transmission mechanism 17 and the hydraulic telescopic rod 36 to achieve precise delivery and recovery of hydraulic oil, ensuring that the extension and retraction of the pressure tooth 29 is smooth and controllable. The fluid storage cylinder 32 is fixedly installed on the wedge-shaped push block 27 to store hydraulic oil and provide a power source for the hydraulic telescopic rod 36. The piston disc 39, which is slidably installed inside the cylinder, can slide up and down along the inner wall of the fluid storage cylinder 32 to push and recover the hydraulic oil. The second spring 40 is fixed between the piston disc 39 and the bottom of the fluid storage cylinder 32 to reset the piston disc 39, ensuring that the piston disc 39 can return to its initial position after each fluid replenishment. The limiting block is fixed inside the reservoir 32 to limit the upward stroke of the piston disc 39 and prevent the piston disc 39 from moving too far upward, which could lead to hydraulic oil leakage or component damage. Two limiting brackets 33 on the outside of the liquid storage cylinder 32 are used to fix the upright 34. The upright 34 is slidably connected to the limiting brackets 33 to ensure that the upright 34 can move up and down accurately along the limiting brackets 33. The abutment plate 35 fixed at the upper end of the two uprights 34 is used to support the driving force of the transmission mechanism 17. The sliding plate 37 fixed at the bottom is located inside the liquid storage cylinder 32 and is connected to the elastic telescopic rod 38. The elastic telescopic rod 38 plays a buffering role to ensure that the pressure is transmitted smoothly. During operation, in the first cold forging stage, the pressure tooth 29 is driven by the reaction force to retract the hydraulic telescopic rod 36, and the hydraulic oil enters the reservoir 32 through the conduit, pushing the piston disc 39 upward and compressing the second spring 40 until the piston disc 39 abuts against the limit block, completing the hydraulic oil recovery; in the second cold forging stage, the transmission mechanism 17 drives the abutment plate 35 downward, driving the upright rod 34 and the slide plate 37 downward, and the slide plate 37 pushes the piston disc 39 downward through the elastic telescopic rod 38, pressing the hydraulic oil in the reservoir 32 back to the hydraulic telescopic rod 36, pushing the hydraulic telescopic rod 36 to extend; The advantages of this structural design are that it enables the recycling and precise delivery of hydraulic oil. The buffering effect of the elastic telescopic rod 38 avoids damage to components caused by excessive pressure. The design of the limit block and limit frame 33 ensures that the movement of each component is precise and does not deviate. Compared with the shortcomings of the existing technology, such as simple fluid replenishment structure design, unstable hydraulic oil delivery, and low telescopic accuracy of the pressure tooth 29, the fluid replenishment structure of this application has all components working together to provide stable and precise hydraulic power to the hydraulic telescopic rod 36, ensuring smooth implementation of segmented cold forging and further improving the quality of tooth forming.

[0033] The transmission mechanism 17 includes a movable ring 21 slidably mounted on the disc 15. Multiple sets of pushing structures 22 that cooperate with the corresponding abutment plates 35 are mounted on the movable ring 21. The transmission mechanism 17 is a key component connecting the disc 15 and the liquid replenishment structure. It is responsible for transmitting the power of the disc 15 to the abutment plates 35, driving the liquid replenishment structure to work, and realizing the secondary extension of the pressure teeth 29. The movable ring 21 is slidably mounted on the outer side of the disc 15 and can slide up and down along the disc 15. Its installation position is precisely corresponding to the abutment plates 35, ensuring that when the movable ring 21 moves down, the pushing structures 22 on it can accurately contact the abutment plates 35 and transmit power. Multiple sets of pushing structures 22 are evenly installed on the moving ring 21. Each set of pushing structures 22 corresponds to a set of liquid replenishing structure abutment 35, ensuring that multiple sets of liquid replenishing structures can work synchronously, thereby driving multiple sets of pressure teeth 29 to extend and retract synchronously, ensuring that the serrations on the outer rod of the bolt 28 are uniformly formed. During operation, after the first cold heading is completed, the driver inside the disc 15 is activated, driving the moving ring 21 to slide downward along the disc 15. The moving ring 21 drives the pushing structures 22 on it to move downward synchronously until the pushing structures 22 are tightly abutted against the abutment 35. The moving ring 21, which continues to move downward, transmits downward driving force to the abutment 35 through the pushing structures 22, causing the abutment 35 to move downward, thereby triggering the liquid replenishing structure to work, pushing the pressure teeth 29 to fully extend, and completing the second cold heading. The advantage of this structural design is that it achieves precise power transmission and synchronous control of multiple sets of fluid replenishment structures, ensuring that the actions of multiple sets of pressure teeth 29 are consistent, and improving the consistency of tooth forming. Compared with the shortcomings of the existing technology, such as complex transmission structure, large power transmission loss, and asynchronous action of multiple sets of components, the transmission mechanism 17 of this application has a simple structure and high transmission efficiency. The sliding connection design between the moving ring 21 and the disc 15 ensures that the moving ring 21 moves smoothly and without jamming. The synchronous design of multiple sets of push structures 22 effectively solves the problem of uneven tooth forming caused by asynchronous action of multiple sets of pressure teeth 29, further improving processing accuracy and production efficiency.

[0034] The pushing structure 22 includes a slide rail 23 fixedly installed on the moving ring 21. The slide rail 23 is slidably connected to the disc 15. A push rod 24 is slidably installed on the slide rail 23, and multiple spring rods 25 are fixedly installed on the slide rail 23. The telescopic end of each spring rod 25 is fixedly connected to the push rod 24. The push structure 22 is the core actuator of the transmission mechanism 17. It is responsible for smoothly transmitting the driving force of the moving ring 21 to the abutment 35, and at the same time plays a role in buffering and position compensation. The slide rail 23 is fixedly installed on the moving ring 21 and slidably connected to the disc 15. It can provide a stable mounting platform for the push rod 24, and can move up and down synchronously with the moving ring 21. At the same time, its position can be finely adjusted along the disc 15 to ensure that the push rod 24 can be accurately aligned with the abutment 35. The push rod 24 is slidably mounted on the slide rail 23 and can slide back and forth along the slide rail 23. Its bottom corresponds to the abutment plate 35 and is used to directly transmit driving force. The spring rod 25 is fixed on the slide rail 23 and its telescopic end is connected to the push rod 24. When in the natural state, it pushes the push rod 24 to stay in the initial position, which plays a role in reset and buffering. During operation, the moving ring 21 drives the slide rail 23 and push rod 24 to move downwards. When the bottom of the push rod 24 contacts the abutment plate 35, the moving ring 21 continues to move downwards. The push rod 24 slides backwards along the slide rail 23 under the reaction force of the abutment plate 35, compressing the spring rod 25. The elastic buffering effect of the spring rod 25 is used to convert the instantaneous driving force of the moving ring 21 into a stable thrust, avoiding excessive pressure that could damage the abutment plate 35, the upright rod 34, and other components. After the second cold heading is completed, the moving ring 21 moves upwards, the spring rod 25 resets, and pushes the push rod 24 back to its initial position, preparing for the next operation. The advantage of this structural design is that it achieves smooth transmission of driving force, while also having position compensation and buffering functions. This ensures that the push rod 24 and the back plate 35 are precisely aligned without jamming. Compared with the existing technology, the push structure 22 lacks buffering and its position is not adjustable, which easily leads to component wear and unstable power transmission. The push structure 22 of this application effectively protects the equipment components and improves the stability of power transmission through the buffering effect of the spring rod 25 and the position compensation of the slide rail 23. At the same time, it ensures that multiple sets of push rods 24 transmit power synchronously, ensures that multiple sets of liquid replenishment structures work synchronously, and further improves the consistency of the tooth forming.

[0035] Each push rod 24 has multiple rolling balls 26 mounted on its bottom to reduce friction and make the push rod 24 slide more smoothly relative to the abutment 35.

[0036] The specific operating steps of this device are as follows: First, the bolt 28 is placed on the wedge-shaped pusher 27. Then, the lower pressure plate 5 is moved down by the hydraulic rod 2, so that the pressure head 16 presses on the bolt 28 (the size of the pressure head 16 is consistent with the size of the end of the bolt 28 after cold heading straight knurling, and is used to limit the top of the bolt 28 to prevent the bolt 28 from deforming upwards during the cold heading process). The bolt 28 is initially locked. At this time, the roller 14 does not contact the wedge-shaped pusher 27, so the wedge-shaped pusher 27 will not move (an elastic reset structure is installed between the wedge-shaped pusher 27 and the wedge-shaped guide rail 11, which is existing technology and will not be described in detail here). Next, the lower pressure plate 5 continues to move downward, and the roller 14 will contact the wedge-shaped push block 27 (the purpose of the roller 14 is to reduce the friction between the punch plate 13 and the wedge-shaped push block 27, so that the wedge-shaped push block 27 can converge more smoothly to the center). As the punch plate 13 and the disc 15 move downward, the pressure head 16 will not move downward, so the first spring 19 between the disc 15 and the pressure head 16 will be compressed (the elasticity of the first spring 19 can be adjusted by adjusting the limit slide rod 20, which is existing technology and will not be described in detail here, to ensure that the pressure between the pressure head 16 and the bolt 28 can ensure that the bolt 28 will not deform upward). As the lower pressure plate continues to move downward, the roller 14 will press against the wedge-shaped push block 27 and move downward. Under the action of the shoe-shaped guide rail 11, many wedge-shaped push blocks 27 will gather towards the center until the pressure teeth 29 on the wedge-shaped push block 27 abut against the side of the bolt 28 to correct the bolt 28. First compression: After the pressure tooth 29 abuts against the bolt 29, the bolt 28 will exert a reaction force on the pressure tooth 29. This reaction force will cause the pressure tooth 29 to retract into the wedge-shaped push block 27. At this time, the hydraulic telescopic rod 36 retracts, and the liquid in the hydraulic telescopic rod 36 will enter the reservoir 32 through the conduit, causing the piston plate 39 in the reservoir 32 to move upward. After the piston plate 39 moves upward to the position of the limit block, it will stop moving. At this time, the pressure tooth 39 will no longer retract. When the lower pressure plate 5 continues to move downward, the pressure tooth 29 will press straight knurled teeth on the bolt 28, but the depth of the straight knurled teeth at this time is... Only a portion of the pressure tooth 29 protrudes, not its entire depth (when the pressure tooth 29 abuts against the bolt 28, the wedge-shaped pusher 27 moves downwards and converges towards the center, which in turn causes the pressure tooth 29 to converge towards the center. However, to ensure the stability of the pressure tooth 29, it cannot move vertically. Here, the vertical rail 30 is used to compensate for the movement of the pressure tooth 29. When the wedge-shaped pusher 27 moves downwards, it only causes the vertical rail 30 to move downwards, and does not cause the pressure tooth 29 to move downwards, so that the pressure tooth 29 always remains relatively stationary with the bolt 28, which can effectively improve the quality of straight-tooth cold heading). In the second extrusion, a driver that works with the moving ring 21 is installed inside the disc 15. After the first extrusion is completed, the driver is activated, which drives the moving ring 21 to move down, causing the slide rail 23 to move down, which in turn drives the push rod 24 to move down. The push rod 24 will abut against the abutment plate 35, causing the abutment plate 35 to move down. The abutment plate 35 will drive the upright rod 34 to move down, which will drive the slide plate 37 to move down. The slide plate 37 will drive the piston disc 39 to move down through the elastic telescopic rod 38, forcing the liquid in the reservoir 32 into the hydraulic telescopic rod 36. The extension of the hydraulic telescopic rod 36 will push the vertical rail 30 to move, thereby squeezing the pressure tooth 29 out of the wedge-shaped push block 27, thus performing a second extrusion cold heading (the elastic telescopic rod 38 is set here as a buffer between the slide plate 37 and the piston disc 39 to make the applied pressure stable and smooth).

[0037] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A high-quality bolt outer rod part cold forging anti-deformation mechanism, comprising an outer frame (1) and bolts (28), characterized in that, It also includes a cold heading module (3) installed inside the outer frame (1); The top of the outer frame (1) is equipped with a hydraulic rod (2) for driving the cold heading module (3) to perform high-pressure cold heading. The bottom of the inner side of the outer frame (1) is equipped with a mechanical adjustment module (4) for adjusting the horizontal position of the cold heading module (3). The cold heading module (3) includes a lower pressure plate (5), a support plate (6) and multiple sets of cold heading molds (7). The lower pressure plate (5) is fixedly connected to the telescopic end of the hydraulic rod (2), and the support plate (6) is connected to the mechanical adjustment module (4). The cold heading mold (7) is composed of a pressing component (8) and a deformation component (9). The deformation component (9) is composed of a limiting cylinder (12), a wedge guide rail (11) and a chuck (10). The chuck (10) is composed of multiple sets of wedge push blocks (27). Each set of wedge push blocks (27) is equipped with multiple pressure teeth (29) for cold heading straight knives. Each wedge push block (27) and its corresponding pressure teeth (29) are equipped with a pushing mechanism.

2. The high-quality bolt outer shank cold forging anti-deformation mechanism for the serrated edge as described in claim 1, characterized in that, The pressing assembly (8) includes a punch plate (13) fixedly connected to the pressing plate (5). A disc (15) is fixedly installed on the punch plate (13). A pressure head (16) is installed on the disc (15) through a buffer mechanism (18). The bottom of the pressure head (16) adopts a wedge-shaped concave design.

3. The high-quality bolt outer shank cold forging anti-deformation mechanism according to claim 2, characterized in that, Multiple sets of rolling structures are rotatably installed on the punch plate (13). Each set of rolling structures consists of multiple sets of rollers (14) that cooperate with the corresponding wedge-shaped push block (27).

4. The high-quality bolt outer shank cold forging anti-deformation mechanism for the serrated edge as described in claim 2, characterized in that, The buffer mechanism (18) includes multiple limiting slide rods (20) fixedly installed on the pressure head (16). Each limiting slide rod (20) is connected to the disc (15) through sliding. Multiple first springs (19) are fixedly installed between the disc (15) and the pressure head (16). Each first spring (19) is sleeved on the outside of the corresponding limiting slide rod (20).

5. The high-quality bolt outer shank cold forging anti-deformation mechanism according to claim 2, characterized in that, The pushing mechanism includes a vertical rail (30) slidably mounted on a wedge-shaped push block (27). The pressure tooth (29) is slidably connected to the vertical rail (30). A fixing plate (31) is fixedly mounted on the wedge-shaped push block (27). The fixing plate (31) has multiple storage slots. A hydraulic telescopic rod (36) is fixedly mounted in each storage slot. The telescopic end of each hydraulic telescopic rod (36) is fixedly connected to the vertical rail (30). Two sets of fluid replenishment structures that cooperate with the multiple hydraulic telescopic rods (36) are installed on the wedge-shaped push block (27).

6. The high-quality bolt outer shank cold forging anti-deformation mechanism for the serrated edge as described in claim 5, characterized in that, The fluid replenishment structure includes a reservoir cylinder (32) fixedly mounted on a wedge-shaped pusher (27). A piston disc (39) is slidably mounted inside the reservoir cylinder (32). Multiple second springs (40) are fixedly mounted between the piston disc (39) and the bottom of the reservoir cylinder (32). A conduit connects the reservoir cylinder (32) to multiple hydraulic telescopic rods (36). A limiting block that cooperates with the piston disc (39) is fixedly mounted inside the reservoir cylinder (32). Two limiting frames (33) are fixedly mounted outside the reservoir cylinder (32). (33) Each of the two uprights (34) is slidably installed with a vertical rod (34). The upper ends of the two uprights (34) are fixedly installed with a support plate (35), and the bottom of the two uprights (34) is fixedly installed with a sliding plate (37). The sliding plate (37) is located inside the liquid storage cylinder (32). Multiple elastic telescopic rods (38) are fixedly installed at the bottom of the sliding plate (37). The telescopic end of each elastic telescopic rod (38) is fixedly connected to the piston disc (39). A transmission mechanism (17) is installed between the disc (15) and the support plate (35).

7. The high-quality bolt outer shank cold forging anti-deformation mechanism according to claim 6, characterized in that, The transmission mechanism (17) includes a movable ring (21) slidably mounted on a disc (15), and multiple sets of pushing structures (22) that cooperate with corresponding abutments (35) are mounted on the movable ring (21).

8. The high-quality bolt outer shank cold forging anti-deformation mechanism according to claim 7, characterized in that, The pushing structure (22) includes a slide rail (23) fixedly installed on the moving ring (21), the slide rail (23) is slidably connected to the disc (15), a push rod (24) is slidably installed on the slide rail (23), and a plurality of spring rods (25) are fixedly installed on the slide rail (23), and the telescopic end of each spring rod (25) is fixedly connected to the push rod (24).

9. The high-quality bolt outer shank cold forging anti-deformation mechanism according to claim 8, characterized in that, Each push rod (24) has multiple balls (26) rolled on its bottom.

10. A method for cold forging and preventing deformation of the outer shank of a high-quality bolt with serrated edges, used in the cold forging and preventing deformation mechanism of the outer shank of a high-quality bolt as described in any one of claims 1-9, characterized in that, Includes the following steps: S1. Positioning and placing the workpiece: accurately place the semi-finished bolt (28) on the positioning position of the wedge-shaped pusher (27) to ensure that the axis of the bolt (28) is coaxial with the convergence center of the wedge-shaped pusher (27), so as to ensure that the bolt (28) is subjected to uniform force during the subsequent cold heading process, laying the foundation for the coaxiality of the tooth forming and avoiding the initial positioning deviation from causing the subsequent tooth offset. S2. Initially lock the limit and start the hydraulic rod (2). The hydraulic rod (2) outputs driving force to drive the lower pressure plate (5) to move vertically downward. The lower pressure plate (5) simultaneously drives the lower pressure assembly (8) to move downward until the lower end face of the lower pressure assembly (8) is tightly abutted against the top end face of the semi-finished bolt (28). The bolt (28) is initially axially locked to limit the axial movement of the bolt (28) during the cold heading process and prevent the axial displacement from affecting the forming accuracy of the tooth pattern. S3. Wedge-shaped clamping continues, and a continuous and stable pressure is applied through the hydraulic rod (2) to push the pressing component (8) to move down until the pressing component (8) and the top surface of the wedge-shaped push block (27) are tightly attached and the pressure is transmitted. Under the action of pressure, the wedge-shaped push block (27) slides down along the wedge-shaped guide rail (11). With the guidance of the wedge-shaped guide rail (11), the wedge-shaped push block (27) moves towards the side close to the central axis of the bolt (28) until the pressure teeth (29) on the wedge-shaped push block (27) make initial contact with the outer rod surface of the bolt (28), thus completing the radial clamping and positioning of the bolt (28) and eliminating the clamping instability caused by the gap of the clamp. S4. First segmented cold heading. Maintain the continuous pressure of the hydraulic rod (2). After the pressure tooth (29) contacts the outer rod of the bolt (28), it is subjected to a reaction force and gradually retracts into the wedge-shaped push block (27) until the pressure tooth (29) reaches the preset first extension limit and can no longer retract. At this time, the pressure tooth (29) is partially pressed into the outer rod of the bolt (28) and initially squeezed to form an incomplete straight tooth. Since the pressure tooth (29) does not fully extend out of the wedge-shaped push block (27) this time, the single flow range of the metal molecules of the bolt (28) is small and the deformation is controllable, which effectively avoids the metal flow disorder caused by a single large deformation. S5. Second segmented cold forging. The hydraulic rod (2) continues to apply pressure, driving the pressure tooth (29) to fully extend out of the wedge-shaped pusher (27) and perform a second extrusion deformation on the outer rod of the bolt (28). Through segmented cold forging, the metal molecules of the bolt (28) gradually flow and fully fill the tooth cavity, making the metal flow more uniform. Finally, a high-quality straight tooth with full, flawless, and coaxial high tooth shape is formed, while reducing local stress concentration and improving the structural strength and forming consistency of the bolt (28) tooth.

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