A method and device for forming an inner and outer tooth hub part based on forging-bending preforming

Abstract

The application discloses a kind of based on forging-bending preforming inner and outer tooth hub parts forming method and device, belong to tooth hub part forming manufacturing technical field, solve the technical problems of forming feature precision requirement and stamping common defect of tooth hub part in prior art.The forming method of inner and outer tooth hub part based on forging-bending preforming provided by the application adopts forging-bending preforming, first, blank is made into plane tooth shape feature;The deep drawing forming is carried out to the forging-bending preformed part, and the circumferential compressive stress of material is utilized when deep drawing forming, the plane tooth shape feature of the above-mentioned forging-bending preformed part is formed into circumferential tooth shape, and the inner and outer tooth hub part is obtained.By forging-bending preforming, the problem of corner filling quality decline caused by obvious longitudinal material flow when forming tooth shape in traditional deep drawing process can be avoided.The deep drawing forming is carried out to the forging-bending preformed part, and the circumferential compressive stress of material can be utilized to promote the flow of material at inner and outer tooth corner, and the filling quality at corner is improved.

Description

Technical Field

[0001] This invention relates to the field of gear hub part forming and manufacturing technology, specifically to a forming method and apparatus for internal and external gear hub parts based on forging-bending preforming. Background Technology

[0002] The gear hub, with its circumferentially distributed internal and external teeth, is a core component of the automotive clutch. Its internal and external teeth mate with the steel plates and friction plates, respectively, to transmit torque and motion. To meet the requirements of smooth vehicle operation and passenger comfort, the fit between the gear hub's internal and external teeth and the steel plates and friction plates requires high precision, while also meeting certain structural strength and contact strength requirements. Therefore, the tooth profile design of the gear hub will vary depending on different functional designs and transmission needs, but the requirements for dimensional accuracy and fillet fillet performance are always very high.

[0003] For the forming of gear hub parts, the main production technologies currently include Grob forming, Schuler's roller forming, and LEIFELD's spin forming. However, these forming methods each have their own shortcomings: Grob forming has low forming efficiency; roller forming has a complex die structure, requires high assembly precision, and is limited by the size of the roller, making it difficult to form small module gear hub parts; spin forming suffers from asymmetrical fillet filling. In addition to the above methods, patent 201610223506.8 uses a stamping process, characterized by a longitudinally variable cross-section die structure. This allows for single-pass deep drawing-extrusion composite forming of the gear hub on a single die structure, effectively improving forming efficiency. However, significant longitudinal material flow still occurs during deep drawing, and the forming quality is greatly affected by factors such as friction. Compared to the aforementioned methods, the fillet filling quality still needs further improvement. Summary of the Invention

[0004] In view of the shortcomings and deficiencies of the prior art, the present invention provides a forming method and mold for internal and external gear hub parts based on forging-bending preforming to solve the problem of poor tooth profile filling quality in stamping forming of gear hub parts.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: The forming method for internal and external gear hub parts based on forging-bending preforming provided by the present invention adopts deep drawing forming of forging-bending preforming parts with planar tooth profile features, and utilizes the circumferential compressive stress of the material during deep drawing forming to form the planar tooth profile features of the forging-bending preforming parts into circumferential tooth profiles, thereby obtaining internal and external gear hub parts.

[0006] Preferably, the method includes the following steps: using forging-bending preforming, first forming the slab blank into a planar tooth shape; then drawing the forging-bending preform, using the circumferential compressive stress of the material during drawing to form the planar tooth shape of the forging-bending preform into a circumferential tooth shape, thus obtaining an inner and outer toothed hub part.

[0007] Preferably, the forging-bending pre-forming and deep drawing forming processes of this forming method are as follows:

[0008] S1 Forging-Bending Preforming: A circular slab blank obtained by wire cutting or other methods is subjected to a forging-bending preforming die to undergo a combined forging-bending deformation, forming planar tooth-shaped features at equal intervals in the circumference of the slab blank, thus obtaining a forging-bending preform.

[0009] S2 Deep Drawing: Using a deep drawing die, the forged-bending preform obtained in step S1 is deep drawn into a barrel shape. Using circumferential compressive stress, the planar tooth profile is formed into a circumferential tooth profile to obtain an internal and external toothed hub part.

[0010] Preferably, in step S1, the forging-bending preforming die includes a columnar forging-bending punch and a forging-bending die that fit together vertically. The lower surface of the forging-bending punch is provided with radially distributed ribs in a circumferential direction, and the upper surface of the forging-bending die is provided with radially distributed grooves in a circumferential direction, and the ribs and grooves fit together.

[0011] In step S1, during the forging-bending preforming, a circular blank is placed between the forging-bending punch and the forging-bending die, and the forging-bending punch and the forging-bending die move toward each other, causing the circular blank to undergo a combined forging-bending deformation, resulting in a preform with planar tooth-shaped features.

[0012] Preferably, in step S2, the deep drawing die includes a deep drawing punch, an ejector block, and a deep drawing die.

[0013] The drawing punch is cylindrical in shape, and the drawing die is an annular in shape. The drawing punch can be fitted into the inner annular ring of the drawing die, and the outer side wall of the drawing punch and the inner side wall of the drawing die are both provided with matching toothed structures in the circumferential direction.

[0014] The anti-ejector block is a cylindrical structure that matches the outer diameter and shape of the drawing punch. It is used to apply a reaction force to the bottom of the preform to prevent excessive thinning and cracking.

[0015] Preferably, the drawing punch is a cylindrical structure, and the outer wall of the drawing punch includes two parts: the drawing punch working section and the drawing punch introduction section. The drawing punch working section is a cylindrical side surface and has toothed features distributed circumferentially.

[0016] The drawing punch introduction section is located at the bottom of the drawing punch working section, that is, at the bottom of the outer wall of the drawing punch. The drawing punch introduction section is a cylindrical side without tooth features, and its bottom is a rounded end face.

[0017] Preferably, the inner wall of the drawing die comprises, from bottom to top, four parts: a drawing die clearance section, a drawing die working section, a drawing die transition section, and a drawing die placement section. All four parts have circumferentially distributed toothed features that are continuous and smoothly transitioned.

[0018] The drawing die placement section is a circular platform, and the inner diameter of the circular platform is larger than the outer diameter of the forged-bending preform with planar tooth features obtained in step S1.

[0019] The deep drawing die transition section is an inclined surface structure that slopes outward from the upper end of the deep drawing die working section to the inner end of the circular platform of the deep drawing die placement section, and the tooth profile features from the deep drawing die working section to the deep drawing die placement section are arranged in a radial, continuous, and gradual manner.

[0020] The shape and size of the tooth profile of the drawing die working section are consistent with the outer structure of the target tooth hub, and work together with the drawing punch working section to determine the final shape and size of the target tooth hub.

[0021] Preferably, the inner diameter of the drawing die clearance section is 1-2 mm larger than the inner diameter of the drawing die working section, and the height of the drawing die working section is about 3-5 mm. This is to prevent excessive drawing resistance caused by an excessively long working strip, which could lead to the tearing of the parts.

[0022] The aforementioned forming apparatus for internal and external gear hub parts based on forging-bending preforming includes the forging-bending preforming mold in any of the aforementioned forming methods for internal and external gear hub parts based on forging-bending preforming.

[0023] The aforementioned forming apparatus for internal and external gear hub parts based on forging-bending preforming includes the deep drawing die in any of the aforementioned forming methods for internal and external gear hub parts based on forging-bending preforming.

[0024] This invention provides a method and apparatus for forming internal and external gear hub parts based on forging-bending preforming. It has the following beneficial effects:

[0025] The present invention relates to a method and apparatus for forming internal and external gear hub parts based on forging-bending preforming. This method employs forging-bending preforming, first forming planar tooth profiles, and then utilizing the circumferential compressive stress of the material during deep drawing to shape the planar tooth profiles into circumferential tooth profiles, thus obtaining internal and external gear hub parts. The manufacturing process is simple, highly operable, ensures precise machining quality of small-module gear hub parts, and has high production efficiency. Furthermore, the preparation apparatus has a simple and ingenious structure, a scientifically sound design, and is applicable to the apparatus and method for forming internal and external teeth of straight-through and non-straight-through clutch gear hubs.

[0026] It has the following advantages:

[0027] 1) By forging-bending pre-forming, the problem of reduced fillet filling quality caused by significant longitudinal material flow during the traditional deep drawing process can be avoided.

[0028] 2) Deep drawing of forged-bending preforms can utilize the circumferential compressive stress of the material to promote the flow of the material at the inner and outer tooth fillets, thereby improving the filling quality at the fillets. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the forging-bending preforming mold in the forming device for internal and external gear hub parts based on forging-bending preforming in Embodiment 1 of the present invention.

[0030] Figure 2 This is a schematic diagram illustrating the process by which the shape of a forged and bent preformed part changes when the slab is deformed using the forging-bending preforming die of Example 1.

[0031] Figure 3 This is a schematic diagram (section view) of the deep drawing die in the forming device for internal and external gear hub parts based on forging-bending preforming according to Embodiment 2 of the present invention;

[0032] Figure 4 This is a schematic diagram of the deep drawing punch used in Embodiment 2 of the present invention;

[0033] Figure 5 This is a schematic diagram (cross-sectional view) of the deep drawing die used in Embodiment 2 of the present invention;

[0034] Figure 6 This is a schematic diagram illustrating the process of shape change in the process of deforming a forged-bending preform into an internal and external gear hub part using the deep drawing die of Example 2.

[0035] Figure 7 This is a schematic diagram of the product shape structure corresponding to the two processes of forging-bending preforming and deep drawing in the forming method of internal and external gear hub parts based on forging-bending preforming in Embodiment 3 of the present invention.

[0036] In the figure: 1. Forging-bending preforming die, 2. Drawing forming die, 101. Forging-bending punch, 102. Forging-bending die, 201. Drawing punch, 202. Anti-ejector block, 203. Drawing die, 2011. Drawing punch working section, 2012. Drawing punch introduction section, 203. Drawing die, 2031. Drawing die clearance section, 2032. Drawing die working section, 2033. Drawing die transition section, 2034. Drawing die placement section, 3. Forging-bending preform, 4. Slab, 5. Internal and external gear hub parts. Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0038] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] Example 1

[0040] like Figures 1-2 As shown, the forging-bending preforming mold in the forming device for internal and external gear hub parts based on forging-bending preforming of the present invention is specifically as follows: The forging-bending preforming mold includes a columnar forging-bending punch 101 and a forging-bending die 102 that fit together vertically. The lower surface of the forging-bending punch 101 is provided with radially distributed ribs evenly distributed in the circumferential direction, and the upper surface of the forging-bending die 102 is provided with radially distributed grooves evenly distributed in the circumferential direction, and the ribs and grooves fit together.

[0041] like Figure 2 As shown, during the forging-bending preforming process, the circular blank 4 is simply placed between the forging-bending punch 101 and the forging-bending die 102, and the forging-bending punch 101 and the forging-bending die 102 are controlled to move towards each other by the driving device, so that the circular blank 4 undergoes upsetting-bending composite deformation between the forging-bending punch 101 and the forging-bending die 102, so that the outer ring of the circular blank 4 is gradually upsetting-bending composite deformation to produce the required planar tooth profile, and finally the forging-bending preform 3 with planar tooth profile is obtained.

[0042] The forging-bending preforming mold in this forging-bending preforming device for internal and external gear hub parts simplifies the forging-bending preforming process, saves time and effort, and accurately produces forging-bending preformed parts 3 with the required planar tooth profile features. It enables precise mass production, significantly improves the working efficiency of the forging-bending preforming process, and ensures the smooth progress of the subsequent deep drawing process.

[0043] Example 2

[0044] like Figures 3-6 As shown, the deep drawing die in the forging-bending pre-forming device for internal and external gear hub parts of the present invention has the following specific structure and usage method:

[0045] The deep drawing die includes a deep drawing punch 201, an ejector block 202, and a deep drawing die 203.

[0046] The drawing punch 201 is cylindrical, while the drawing die 203 is annular. The drawing punch 201 fits into the inner annulus of the drawing die 203. Both the outer wall of the drawing punch 201 and the inner wall of the drawing die 203 have circumferentially matching toothed structures. The anti-ejector block 202 is a cylindrical structure matching the outer diameter and shape of the drawing punch 201, used to apply a reaction force to the bottom of the preform to prevent excessive thinning and cracking. The shape and size of the toothed features of the drawing die 203 are consistent with the outer structure of the target toothed hub part, and cooperate with the drawing punch 201 to determine the final shape and size of the target toothed hub part.

[0047] The drawing punch 201 is a cylindrical structure, and the outer wall of the drawing punch 201 includes two parts: the drawing punch working section 2011 and the drawing punch introduction section 2012. The drawing punch working section 2011 is a cylindrical side surface and has toothed features distributed circumferentially. The drawing punch introduction section 2012 is located at the bottom of the drawing punch working section 2011, that is, at the bottom of the outer wall of the drawing punch. The drawing punch introduction section 2012 is a cylindrical side without tooth features and its bottom is a rounded end face. This type of drawing die design can effectively utilize the circumferential compressive stress during the deformation of the forged-bending preform 3 to promote the flow of material at the rounded corners of the inner and outer teeth, thereby significantly improving the filling quality at the rounded corners. This ensures that the overall structure of the entire target inner and outer toothed hub parts is stable, with uniform texture distribution, no cracks or weak areas, and further ensures the accuracy and precision of the inner and outer tooth results of the target inner and outer toothed hub parts. The operation is time-saving and labor-saving, significantly improving the efficiency and yield of deep drawing of forged-bending preforms. It effectively utilizes the circumferential compressive stress of the material during deep drawing to form the planar tooth features of the forged-bending preform 3 into circumferential tooth features, thus obtaining inner and outer toothed hub parts.

[0048] The inner wall of the drawing die 203 consists of four parts from bottom to top: a drawing die clearance section 2031, a drawing die working section 2032, a drawing die transition section 2033, and a drawing die placement section 2034. All four parts have tooth-shaped features that are circumferentially distributed and smoothly transitioned.

[0049] The drawing die placement section 2034 is a circular platform, and the inner diameter of the circular platform is larger than the outer diameter of the forged-bending preform 3 with planar tooth features obtained in Example 1. This facilitates effective load-bearing support for the forged-bending preform 3, ensuring the continuous and effective execution of the drawing process, and ensuring accuracy and precision during deformation.

[0050] The deep drawing die transition section 2033 is an inclined surface structure that extends outward from the upper end of the deep drawing die working section 2032 to the inner end of the circular platform of the deep drawing die placement section 2034. The tooth profile features from the deep drawing die working section 2032 to the deep drawing die placement section 2034 are arranged in a radial, continuous, and gradual manner. The shape and size of the tooth profile features of the deep drawing die working section 2032 are consistent with the outer structure of the target tooth hub part, and work together with the deep drawing punch working section 2011 to determine the final tooth hub shape and size of the target tooth hub part.

[0051] The inner diameter of the drawing die clearance section 2031 is slightly larger than the inner diameter of the drawing die working section 2032 by 1mm, and the height of the drawing die working section 2032 is 3mm. This is to prevent excessive drawing resistance caused by an excessively long drawing die working section 2032, which could lead to the breakage of the parts, thus ensuring the overall machining yield of the internal and external gear hub parts 5 and significantly improving work efficiency.

[0052] The drawing die placement section 2034 and the drawing die transition section 2033 respectively serve to place the preform and guide the preform material to flow into the die working section, precisely controlling the flow direction of the material during the forming process, ensuring the accuracy of the entire internal and external gear hub part 5 machining process, and significantly improving its yield.

[0053] like Figure 6 As shown, the deep drawing die in the forging-bending pre-forming device for internal and external gear hub parts of the present invention is used in the following specific process:

[0054] The forged-bending preform 3 with planar tooth features obtained in Example 1 is placed on the annular platform of the drawing die placement section 2034, with its outer edge abutting against the annular platform of the drawing die placement section 2034. This structure can ensure the stability of the subsequent drawing process. Next, the drawing punch 201 and the anti-ejector block 202 are symmetrically abutted against the upper and lower side walls of the middle part of the forged-bending preform 3, respectively, with the anti-ejector block 202 extending into the annular part in the middle of the drawing die 203. Finally, the drive system device is activated to push the drawing punch 201 and the anti-ejector block 202 together to draw the forged-bending preform 3, ultimately drawing the forged-bending preform 3 with planar tooth features obtained in Example 1 into a barrel-shaped part. Using circumferential compressive stress, the planar tooth features are formed into circumferential tooth features, resulting in the inner and outer toothed hub parts 5.

[0055] When using the deep drawing die of the present invention to deep draw the forged-bending preform, the forged-bending preform 3 with planar tooth features is simply placed between the deep drawing punch 201 and the anti-ejector block 202. The operation and positioning are convenient, time-saving and labor-saving, and ensure the accuracy and product yield of the entire internal and external toothed hub parts 5, meet the actual needs, and significantly improve work efficiency.

[0056] Example 3

[0057] The present invention provides a method for forming internal and external gear hub parts based on forging-bending preforming. The method employs forging-bending preforming, first shaping a slab blank into planar tooth profiles; then, deep drawing the forged-bending preform, utilizing the circumferential compressive stress of the material during deep drawing to transform the planar tooth profiles of the forged-bending preform into circumferential tooth profiles, thus obtaining internal and external gear hub parts. The two processes of forging-bending preforming and deep drawing in this forming method are detailed in the following steps:

[0058] S1 Forging-Bending Preforming: A circular blank 4, obtained by wire cutting or other methods, is placed between a forging-bending punch 101 and a forging-bending die 102 using the forging-bending preforming mold 1 in Example 1. The forging-bending punch 101 and the forging-bending die 102 are controlled to move towards each other by a driving device, so that the circular blank 4 undergoes upsetting-bending composite deformation between the forging-bending punch 101 and the forging-bending die 102, and planar tooth features are formed at equal intervals in the circumference of the blank 4. A planar tooth feature that meets the requirements is produced, and a forging-bending preform 3 with planar tooth features is obtained.

[0059] S2 Deep Drawing: Using the deep drawing die 2 in Example 2, firstly, the forged-bending preform 3 with planar tooth features obtained in step S1 is placed on the annular platform of the deep drawing die placement section 2034 of the deep drawing die 2, with its outer edge abutting against the annular platform of the deep drawing die placement section 2034. Secondly, the deep drawing punch 201 and the anti-ejector block 202 are symmetrically abutted against the upper and lower side walls of the middle part of the forged-bending preform 3, respectively, with the anti-ejector block 202 extending into the annular space in the middle of the deep drawing die 203. Finally, the drive system is activated to push the deep drawing punch 201 and the anti-ejector block 202 together to draw the forged-bending preform 3, ultimately drawing the forged-bending preform 3 with planar tooth features obtained in Example 1 into a barrel-shaped part. Using circumferential compressive stress, the planar tooth features are formed into circumferential tooth features, resulting in the inner and outer toothed hub parts 5.

[0060] The forging-bending preforming method for forming internal and external gear hub parts of the present invention is convenient to operate, saves time and effort, and does not require cumbersome operations. 1) By using forging-bending preforming, the problem of reduced fillet quality caused by significant longitudinal material flow during traditional deep drawing processes can be avoided. 2) Deep drawing the forged-bending preform 3 can utilize the circumferential compressive stress of the material to promote material flow at the fillet of the internal and external gears, thereby improving the fillet quality.

[0061] This invention relates to a method and apparatus for forming internal and external gear hub parts based on forging-bending preforming. The apparatus features an ingenious structural design, a simple manufacturing method, and a high yield. It employs forging-bending preforming, first forming planar tooth profiles, and then utilizing the circumferential compressive stress of the material during deep drawing to shape the planar tooth profiles into circumferential tooth profiles, thus obtaining internal and external gear hub parts. The manufacturing process is simple, highly operable, ensures precise machining quality for small-module gear hub parts, and boasts high production efficiency. Furthermore, the manufacturing apparatus has a simple and ingenious structure, a scientifically sound design, and is applicable to both through-type and non-through-type clutch gear hubs.

[0062] The above are merely embodiments of the present invention. For example, the shape and size of the protrusion of the forging-bending punch 101 and the groove of the forging-bending die 102 can be designed and selected according to the shape and size of the target gear hub part; the inner diameter of the drawing die clearance section 2031 is 1-2 mm larger than the inner diameter of the drawing die working section 2032, and the height of the drawing die working section 2032 is 3-5 mm; the specific dimensions of the forging-bending preforming die 1 in Embodiment 1 and the drawing die 2 in Embodiment 2 can be selected and designed according to the actual production product requirements, and can realize the forming method and apparatus for internal and external gear hub parts based on forging-bending preforming of the present invention.

[0063] 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 forming method for internal and external gear hub parts based on forging-bending preforming, characterized in that, The planar tooth profile of the forged-bending preform (3) with planar tooth profile is formed by deep drawing. The planar tooth profile of the forged-bending preform is formed into a circumferential tooth profile by utilizing the circumferential compressive stress of the material during deep drawing, thus obtaining the inner and outer toothed hub parts (5). The forming method involves two processes: forging-bending pre-forming and deep drawing. The specific steps are as follows: S1 Forging-bending preforming: The circular slab (4) obtained by wire cutting or other methods is subjected to forging-bending preforming mold (1) to undergo upsetting-bending composite deformation, and planar tooth features are formed at equal intervals in the circumference of the slab (4) to obtain the forging-bending preform (3). The forging-bending preforming mold (1) includes a columnar forging-bending punch (101) and a forging-bending die (102) that fit together vertically. The lower surface of the forging-bending punch (101) is provided with radially distributed ribs in a circumferential direction, and the upper surface of the forging-bending die (102) is provided with radially distributed grooves in a circumferential direction, and the ribs and grooves fit together. In step S1, during the forging-bending preforming, a circular blank (4) is placed between the forging-bending punch (101) and the forging-bending die (102), and the forging-bending punch (101) and the forging-bending die (102) move toward each other, so that the circular blank undergoes a combined forging-bending deformation to obtain a preform with planar tooth features; S2 Deep drawing: Using the deep drawing die (2), the forged-bending preform (3) obtained in step S1 is deep drawn into a barrel shape. Using the circumferential compressive stress, the planar tooth features are formed into circumferential tooth shapes to obtain the inner and outer tooth hub parts (5).

2. The forming method for internal and external gear hub parts based on forging-bending preforming according to claim 1, characterized in that, In step S2, the deep drawing die (2) includes a deep drawing punch (201), an anti-ejector block (202), and a deep drawing die (203). The drawing punch (201) is cylindrical in shape, and the drawing die (203) is annular in shape. The drawing punch (201) can be fitted into the inner annular ring of the drawing die (203). Both the outer sidewall of the drawing punch (201) and the inner sidewall of the drawing die (203) are provided with matching toothed structures in the circumferential direction. The anti-top block (202) is a cylindrical structure that matches the outer diameter and shape of the drawing punch (201) and is used to apply a reaction force to the bottom of the preform to prevent excessive thinning and cracking.

3. The forming method for internal and external gear hub parts based on forging-bending preforming according to claim 2, characterized in that, The drawing punch (201) is a columnar structure, and the outer wall of the drawing punch (201) includes two parts: the drawing punch working section (2011) and the drawing punch introduction section (2012). The drawing punch working section (2011) is a cylindrical side surface and has toothed features distributed circumferentially. The drawing punch introduction section (2012) is located at the bottom of the drawing punch working section (2011), that is, at the bottom of the outer wall of the drawing punch (201). The drawing punch introduction section (2012) is a cylindrical side without tooth features and its bottom is a rounded end face.

4. The forming method for internal and external gear hub parts based on forging-bending preforming according to claim 3, characterized in that, The inner wall of the drawing die (203) comprises, from bottom to top, four parts: a drawing die clearance section (2031), a drawing die working section (2032), a drawing die transition section (2033), and a drawing die placement section (2034). All four parts have circumferentially distributed tooth-shaped features that are continuous and smoothly transitioned. The deep drawing die placement section (2034) is an annular platform, and the inner diameter of the annular platform is larger than the outer diameter of the forged-bending preform with planar tooth features obtained in step S1. The deep drawing die transition section (2033) is an inclined body structure that is inclined outward from the upper end of the deep drawing die working section (2032) to the inner end of the circular platform of the deep drawing die placement section (2034), and the tooth shape features from the deep drawing die working section (2032) to the deep drawing die placement section (2034) are arranged in a radial continuous gradient. The shape and size of the tooth profile of the deep drawing die section (2032) are consistent with the outer structure of the target tooth hub, and work together with the deep drawing punch section (2011) to determine the shape and size of the final target tooth hub.

5. The forming method for internal and external gear hub parts based on forging-bending preforming according to claim 4, characterized in that, The inner diameter of the drawing die clearance section (2031) is 1-2 mm larger than the inner diameter of the drawing die working section (2032), and the height of the drawing die working section (2032) is 3-5 mm.

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