Forging-bending pre-forming-based inner and outer gear hub part forming method and device

Abstract

The invention discloses an internal and external gear hub part forming method and device based on forging-bending pre-forming, belongs to the technical field of gear hub part forming and manufacturing, and solves the technical problems of forming feature precision requirements and common stamping defects of gear hub parts in the prior art. According to the internal and external gear hub part forming method based on forging-bending pre-forming, forging-bending pre-forming is adopted, and a plate blank is made into a plane tooth-shaped feature; and drawing forming is conducted on the forging-bending preformed piece, the plane tooth profile characteristic of the forging-bending preformed piece is formed into a circumferential tooth profile through the circumferential compression stress of materials during drawing forming, and the inner gear hub part and the outer gear hub part are obtained. Through forging-bending pre-forming, the problem that the fillet filling quality is reduced due to obvious longitudinal material flowing when a tooth shape is formed through a traditional deep drawing process can be solved. The forging-bending preformed part is subjected to deep drawing forming, the circumferential compression stress of the material can be used for promoting the material to flow at the fillets of the inner teeth and the outer teeth, and the filling quality of the fillets is improved.

Description

Technical Field

[0001] The invention relates to the technical field of gear hub part forming and manufacturing, and in particular to a method and device for forming internal and external gear hub parts based on forging-bending preforming. Background Art

[0002] The gear hub parts with circumferentially distributed internal and external teeth are the core parts of the automobile clutch. Its internal and external teeth cooperate with the steel plate and friction plate respectively to achieve the function of transmitting torque and motion. In order to meet the requirements of vehicle driving stability and passenger comfort, the matching accuracy of the internal and external teeth of the gear hub with the steel plate and friction plate is very high, and at the same time, it must meet certain structural strength and contact strength requirements. Therefore, according to different functional designs and transmission requirements, the tooth shape design of the gear hub parts will be different, but the requirements for dimensional accuracy and fillet filling are 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, but these forming methods have their own shortcomings: Grob forming has low forming efficiency; the roller forming mold has a complex structure, high assembly precision requirements, and is limited by the size of the roller, making it difficult to form small-module gear hub parts; spin forming has the problem of asymmetric fillet filling. In addition to the above-mentioned process methods, Patent 201610223506.8 adopts a stamping process, which is characterized by a longitudinal die variable cross-section structure, which realizes the single-pass drawing-extrusion composite forming of the gear hub on a pair of mold structures, and effectively improves the forming efficiency, but the material still undergoes obvious longitudinal flow during the drawing process, and the forming quality is greatly affected by factors such as friction. Compared with the aforementioned process methods, the fillet filling quality needs to be further improved. Summary of the invention

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

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

[0006] Preferably, the method specifically includes the following steps: using forging-bending preforming to first form a plate blank into a planar tooth-shaped feature; then deep drawing the forging-bending preform, and utilizing the circumferential compressive stress of the material during deep drawing to form the planar tooth-shaped feature of the forging-bending preform into a circumferential tooth shape, thereby obtaining internal and external gear hub parts.

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

[0008] S1 Forging-bending preforming: The circular plate blank obtained by wire cutting or other methods is subjected to composite deformation of upsetting-bending by using a forging-bending preforming die, and plane tooth-shaped features are formed at equal intervals in the circumference of the plate blank to obtain a forging-bending preformed part;

[0009] S2 Deep drawing: Using a deep drawing die, the forged-bent preformed part obtained in step S1 is drawn into a barrel-shaped part, and the planar tooth profile feature is formed into a circumferential tooth profile using circumferential compressive stress to obtain an internal and external gear hub part.

[0010] Preferably, in step S1, the forging-bending preforming die comprises a cylindrical forging-bending punch and a forging-bending die that cooperate with each other, wherein the lower surface of the forging-bending punch is provided with radial convex ribs evenly distributed circumferentially, and the upper surface of the forging-bending die is provided with radial grooves evenly distributed circumferentially, and the convex ribs and the grooves cooperate with each other;

[0011] During the forging-bending preforming in step S1, the circular slab is placed between a forging-bending punch and a forging-bending die, and the forging-bending punch and the forging-bending die move toward each other, so that the circular slab undergoes a composite forging-bending deformation to obtain a preformed part with a planar tooth profile feature.

[0012] Preferably, in step S2, the drawing forming die comprises a drawing punch, a counter-top block and a drawing die.

[0013] The drawing punch is a cylindrical structure as a whole, the drawing die is a circular ring structure as a whole, the drawing punch can be inserted into the inner circular ring of the drawing die, and the outer wall of the drawing punch and the inner wall of the drawing die are circumferentially provided with mutually matching tooth structures;

[0014] The counter-top 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 columnar structure as a whole, and the outer side wall of the drawing punch includes a drawing punch working section and a drawing punch introduction section, wherein the drawing punch working section is a cylindrical side surface and has tooth-shaped features distributed circumferentially;

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

[0017] Preferably, the inner side wall of the drawing die includes four parts from bottom to top, namely, a drawing die avoidance section, a drawing die working section, a drawing die transition section and a drawing die placement section, and the above four parts are all circumferentially distributed with tooth-shaped features that are continuous and smoothly transitioned from top to bottom.

[0018] The placement section of the drawing die is a circular ring platform, and the inner diameter of the circular ring platform is larger than the outer diameter of the forged-bent preform with a planar tooth profile feature obtained in step S1;

[0019] The transition section of the drawing die is a sloped body structure which is inclined outward from the upper end of the drawing die working section to the inner end of the circular platform of the drawing die placement section, and the tooth profile features from the drawing die working section to the drawing die placement section are radially continuously and gradually changed;

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

[0021] Preferably, the inner diameter of the drawing die avoidance 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 overly long working zone, which may cause parts to crack.

[0022] The above-mentioned internal and external gear hub part forming device based on forging-bending preforming includes the forging-bending preforming mold in any of the above-mentioned internal and external gear hub part forming methods based on forging-bending preforming.

[0023] The above-mentioned internal and external gear hub part forming device based on forging-bending preforming includes the deep drawing forming die in any of the above-mentioned internal and external gear hub part forming methods based on forging-bending preforming.

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

[0025] The method and device for forming internal and external gear hub parts based on forging-bending preforming of the present invention adopt forging-bending preforming to first form a planar tooth profile feature, and then use the circumferential compressive stress of the material during deep drawing to form the planar tooth profile feature into a circumferential tooth profile to obtain an internal and external gear hub part. The manufacturing process is simple and the operability is strong, ensuring the precise processing quality of the formed small-modulus gear hub parts and high production and processing efficiency. In addition, the preparation device has a simple and ingenious structure and a scientific and reasonable design. It is suitable for the device 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) Preforming by forging-bending can avoid the problem of decreased fillet filling quality caused by obvious longitudinal material flow during tooth forming by traditional deep drawing process.

[0028] 2) By deep drawing the forged-bent preform, the circumferential compressive stress of the material can be used to promote the flow of the material at the fillets of the internal and external teeth and improve the filling quality at the fillets. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of a forging-bending preforming die in an internal and external gear hub part forming device based on forging-bending preforming according to Example 1 of the present invention;

[0030] Figure 2 A schematic diagram of a process in which the shape of a forging-bending preformed product is changed by deforming a slab using the forging-bending preformed die of Example 1;

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

[0032] Figure 4 A schematic diagram of the structure of the drawing punch in Example 2 of the present invention;

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

[0034] Figure 6 A schematic diagram of the process in which the shape of a forged-bending preform is deformed into an internal and external gear hub part using the drawing die of Example 2;

[0035] Figure 7 It is a schematic diagram of the product shape structure corresponding to the two processes of forging-bending preforming and deep drawing in the internal and external gear hub parts forming method based on forging-bending preforming in Example 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. counter-top block, 203. drawing die, 2011. drawing punch working section, 2012. drawing punch introduction section, 203. drawing die, 2031. drawing die avoidance section, 2032. drawing die working section, 2033. drawing die transition section, 2034. drawing die placement section, 3. forging-bending preform, 4. plate blank, 5. internal and external gear hub parts. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0038] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] Example 1

[0040] like Figure 1-Figure 2 As shown, the forging-bending preforming die in the internal and external gear hub part forming device based on forging-bending preforming of the present invention is specifically as follows: the forging-bending preforming die includes a cylindrical forging-bending punch 101 and a forging-bending die 102 that match each other up and down, wherein the lower surface of the forging-bending punch 101 is provided with radial ribs evenly distributed circumferentially, and the upper surface of the forging-bending die 102 is provided with radial grooves evenly distributed circumferentially, and the ribs and the grooves match each other.

[0041] like Figure 2 As shown, during forging-bending preforming, it is only necessary to place the circular slab 4 between the forging-bending punch 101 and the forging-bending die 102, and control the forging-bending punch 101 and the forging-bending die 102 to move toward each other through a driving device, so that the circular slab 4 undergoes forging-bending compound deformation between the forging-bending punch 101 and the forging-bending die 102, so that the outer ring of the circular slab 4 gradually undergoes forging-bending compound deformation to produce a planar tooth profile feature that meets the requirements, and finally a forging-bending preform 3 with planar tooth profile features is obtained.

[0042] The forging-bending preforming die in the internal and external gear hub part forming device based on forging-bending preforming makes the forging-bending preforming process simple to manufacture, saves time and effort, and accurately prepares the forging-bending preformed parts 3 with plane tooth profile features that meet the requirements. It can be accurately mass-produced, significantly improving the work efficiency of the forging-bending preforming process, while ensuring the smooth progress of the next step of deep drawing.

[0043] Example 2

[0044] like Figure 3-Figure 6 As shown, the deep drawing forming die in the internal and external gear hub part forming device based on forging-bending preforming of the present invention has a specific structure and a method of use as follows:

[0045] The drawing forming die comprises a drawing punch 201 , a counter-top block 202 and a drawing die 203 .

[0046] The drawing punch 201 is a cylindrical structure as a whole, and the drawing die 203 is a circular ring structure as a whole. The drawing punch 201 can be inserted into the inner circular ring of the drawing die 203, and the outer wall of the drawing punch 201 and the inner wall of the drawing die 203 are circumferentially provided with mutually matching toothed structures. The counter-top block 202 is a cylindrical structure matching the outer diameter and shape of the drawing punch 201, which is used to apply a reaction force at 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 gear hub, and cooperate with the drawing punch 201 to determine the shape and size of the gear hub of the final target gear hub.

[0047] The drawing punch 201 is a columnar structure as a whole, and the outer side wall of the drawing punch 201 includes a drawing punch working section 2011 and a drawing punch introduction section 2012, wherein the drawing punch working section 2011 is a cylindrical side surface and has tooth-shaped features distributed circumferentially. The drawing punch introduction section 2012 is arranged at the bottom of the drawing punch working section 2011, that is, the bottom of the outer wall of the drawing punch. The drawing punch introduction section 2012 is a cylindrical side surface without tooth features, and its bottom is a rounded end face. The drawing forming die with such a structural design can effectively utilize the circumferential compressive stress during the deformation of the material of the forging-bending preform 3 to promote the flow of material at the fillets of the internal and external teeth, thereby significantly improving the filling quality at the fillets, ensuring that the overall structure of the entire target internal and external gear hub part is stable, the texture is evenly distributed, and there are no cracks and weak areas, and further ensuring the accuracy and precision of the internal and external teeth results of the target internal and external gear hub part. The operation is time-saving and labor-saving, and the work efficiency and yield rate of deep drawing of the forging-bending preform are significantly improved. The circumferential compressive stress of the material during deep drawing is effectively utilized to form the planar tooth profile features of the above-mentioned forging-bending preform 3 into circumferential tooth profiles to obtain internal and external gear hub parts.

[0048] The inner wall of the drawing die 203 includes four parts from bottom to top, namely, a drawing die avoidance section 2031, a drawing die working section 2032, a drawing die transition section 2033 and a drawing die placement section 2034, and the above four parts are all circumferentially distributed with tooth-shaped features that are continuous and smoothly transitioned from top to bottom.

[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 forging-bending preform 3 with planar tooth features obtained in Example 1, which is convenient for effectively bearing and supporting the forging-bending preform 3, ensuring that the drawing process is carried out continuously and effectively, and ensuring accuracy and precision during the deformation process.

[0050] The drawing die transition section 2033 is a bevel structure that is tilted outward from the upper end of the drawing die working section 2032 to the inner end of the circular platform of the drawing die placement section 2034, and the tooth-shaped features from the drawing die working section 2032 to the drawing die placement section 2034 are radially and continuously gradiently arranged; the shape and size of the tooth-shaped features of the drawing die working section 2032 are consistent with the outer side structure of the target gear hub part, and cooperate with the drawing punch working section 2011 to determine the gear hub shape and size of the final target gear hub part.

[0051] The inner diameter of the drawing die avoidance section 2031 is slightly larger than the inner diameter of the drawing die working section 2032 by 1 mm, and the height of the drawing die working section 2032 is 3 mm. This is to prevent excessive drawing resistance caused by the excessively long drawing die working section 2032, which may cause the parts to crack, ensure the overall processing yield of the internal and external gear hub parts 5, and significantly improve 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 toward the concave and convex die working sections, accurately controlling the flow direction of the material during the forming process, ensuring the accuracy of the entire internal and external gear hub part 5 processing process, and significantly improving its yield rate.

[0053] like Figure 6 As shown, the deep drawing forming die in the internal and external gear hub part forming device based on forging-bending preforming of the present invention is specifically used as follows:

[0054] The forging-bending preform 3 with planar tooth-shaped features prepared in Example 1 is placed on the annular platform of the drawing die placement section 2034, and its outer edge abuts against the annular platform of the drawing die placement section 2034. This structure can ensure the stability of the subsequent stretching process. Secondly, the drawing punch 201 and the counter-top block 202 are symmetrically abutted on the upper and lower side walls of the middle part of the forging-bending preform 3, and the counter-top block 202 extends into the inner part of the annular ring in the middle of the drawing die 203; finally, the driving system device is started to push the drawing punch 201 and the counter-top block 202 together to draw the forging-bending preform 3, and finally the forging-bending preform 3 with planar tooth-shaped features prepared in Example 1 is drawn into a barrel-shaped part, and the planar tooth-shaped features are formed into a circumferential tooth shape by using the circumferential compressive stress, so as to obtain the internal and external gear hub parts 5.

[0055] When the forged-bent preform is deep-drawn by using the drawing die of the present invention, it is only necessary to place the forged-bent preform 3 with planar tooth profile features between the drawing punch 201 and the counter-top block 202. The operation and positioning are convenient, time-saving and labor-saving, and the processing accuracy and product rate of the entire internal and external gear hub part 5 are ensured, which meets actual needs and significantly improves work efficiency.

[0056] Example 3

[0057] The forming method of the internal and external gear hub parts based on forging-bending preforming of the present invention adopts forging-bending preforming to first form a flat tooth profile feature on a plate blank; then the forging-bending preformed part is deep drawn, and the circumferential compressive stress of the material during deep drawing is used to form the flat tooth profile feature of the forging-bending preformed part into a circumferential tooth profile to obtain the internal and external gear hub parts. The two processes of forging-bending preforming and deep drawing of the forming method are specifically as follows:

[0058] S1 Forging-bending preforming: The circular slab 4 obtained by wire cutting or other means is placed between the forging-bending punch 101 and the forging-bending die 102 using the forging-bending preforming die 1 in Example 1, and the forging-bending punch 101 and the forging-bending die 102 are controlled by a driving device to move toward each other, so that the circular slab 4 undergoes a composite forging-bending deformation between the forging-bending punch 101 and the forging-bending die 102, and plane tooth-shaped features are formed at equal intervals in the circumferential direction of the slab 4 - plane tooth-shaped features that meet the requirements are produced, and a forging-bending preformed part 3 with plane tooth-shaped features is obtained;

[0059] S2 Drawing: Using the drawing die 2 in Example 2, first, the forging-bending preform 3 with plane tooth profile features obtained in step S1 is placed on the annular platform of the drawing die placement section 2034 of the drawing die 2, and its outer edge abuts against the annular platform of the drawing die placement section 2034. Secondly, the drawing punch 201 and the counter-top block 202 are symmetrically abutted against the upper and lower side walls of the middle part of the forging-bending preform 3, and the counter-top block 202 extends into the inner part of the annular ring in the middle of the drawing die 203; finally, the driving system device is started to push the drawing punch 201 and the counter-top block 202 together to draw the forging-bending preform 3, and finally the forging-bending preform 3 with plane tooth profile features obtained in Example 1 is drawn into a barrel-shaped part, and the plane tooth profile features are formed into a circumferential tooth profile by using the circumferential compressive stress, so as to obtain the inner and outer gear 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 tedious operations. 1) Through forging-bending preforming, the problem of decreased fillet filling quality caused by obvious longitudinal material flow during tooth shape forming by traditional deep drawing process can be avoided. 2) The forging-bending preformed part 3 is deep drawn, and the circumferential compressive stress of the material can be used to promote the flow of the material at the fillets of the internal and external gears, thereby improving the filling quality at the fillets.

[0061] The method and device for forming internal and external gear hub parts based on forging-bending preforming of the present invention have an ingenious device structure design, a simple preparation method, and a high yield rate. The forging-bending preforming is used to first form a planar tooth profile feature, and then the circumferential compression stress of the material during deep drawing is used to form the planar tooth profile feature into a circumferential tooth profile to obtain an internal and external gear hub part. The manufacturing process is simple and the operability is strong, ensuring the precise processing quality of forming small-module gear hub parts and high production and processing efficiency. In addition, the preparation device has a simple and ingenious structure and a scientific and reasonable design, and is suitable for straight-through and non-straight-through clutch gear hubs.

[0062] The above are merely embodiments of the present invention. For example, the shape and size of the convex rib 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 avoidance 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 sizes of the forging-bending preforming die 1 in Example 1 and the drawing forming die 2 in Example 2 can be selected and designed according to the actual production product requirements, and both can realize the internal and external gear hub parts forming method and device based on forging-bending preforming of the present invention.

[0063] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for forming internal and external gear hub parts based on forging-bending preforming, characterized in that: A forged-bent preform (3) with a planar tooth profile feature is deep drawn, and the circumferential compressive stress of the material during deep drawing is utilized to form the planar tooth profile feature of the forged-bent preform into a circumferential tooth profile, thereby obtaining an internal and external gear hub part (5).

2. The method for forming internal and external gear hub parts based on forging-bending preforming according to claim 1, characterized in that: The specific steps include: By forging-bending preforming, the plate blank (4) is first formed into a planar tooth-shaped feature; The forged-bent preform (3) is then deep-drawn, and the planar tooth profile of the forged-bent preform (3) is formed into a circumferential tooth profile by utilizing the circumferential compressive stress of the material during deep-drawing, thereby obtaining an internal and external gear hub part (5).

3. The method for forming internal and external gear hub parts based on forging-bending preforming according to claim 2, characterized in that: The forming method includes two processes: forging-bending preforming and deep drawing. The specific steps are as follows: S1 Forging-bending preforming: A circular plate blank (4) obtained by wire cutting or other means is subjected to composite deformation of upsetting and bending by using a forging-bending preforming die (1), and plane tooth-shaped features are formed at equal intervals in the circumferential direction of the plate blank (4), thereby obtaining a forging-bending preformed part (3); S2 drawing: using a drawing die (2), the forged-bent preform (3) obtained in step S1 is drawn into a barrel-shaped part, and the planar tooth profile feature is formed into a circumferential tooth profile by using circumferential compressive stress to obtain an internal and external gear hub part (5).

4. The method for forming internal and external gear hub parts based on forging-bending preforming according to claim 3 is characterized in that: In step S1, the forging-bending preforming die (1) comprises a columnar forging-bending punch (101) and a forging-bending die (102) that are matched with each other, wherein the lower surface of the forging-bending punch (101) is provided with radial convex ribs evenly distributed in the circumference, and the upper surface of the forging-bending die (102) is provided with radial concave grooves evenly distributed in the circumference, and the convex ribs and the concave grooves are matched with each other; During the forging-bending preforming in step S1, the circular plate 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 plate blank undergoes a composite deformation of upsetting and bending, thereby obtaining a preformed part with a planar tooth-shaped feature.

5. The method for forming internal and external gear hub parts based on forging-bending preforming according to claim 3 is characterized in that: In step S2, the drawing forming die (2) comprises a drawing punch (201), a counter-top block (202) and a drawing die (203). The drawing punch (201) is a cylindrical structure as a whole, the drawing die (203) is a circular ring structure as a whole, the drawing punch (201) can be inserted into the inner circular ring of the drawing die (203), and the outer side wall of the drawing punch (201) and the inner side wall of the drawing die (203) are circumferentially provided with mutually matching tooth-shaped structures; The counter-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 at the bottom of the preform to prevent excessive thinning and cracking.

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

7. The method for forming an internal and external gear hub part based on forging-bending preforming according to claim 6, characterized in that: The inner side wall of the drawing die (203) includes four parts from bottom to top, namely, a drawing die avoidance section (2031), a drawing die working section (2032), a drawing die transition section (2033) and a drawing die placement section (2034), and the above four parts are all circumferentially distributed with tooth-shaped features that are connected up and down and smoothly transitioned. The drawing die placement section (2034) is a circular ring platform, and the inner diameter of the circular ring platform is larger than the outer diameter of the forged-bent preform with a planar tooth profile feature obtained in step S1; The drawing die transition section (2033) is a bevel structure that is tilted outward from the upper end of the drawing die working section (2032) to the inner end of the circular platform of the drawing die placement section (2034), and the tooth profile features from the drawing die working section (2032) to the drawing die placement section (2034) are radially continuously and gradually changed; The shape and size of the tooth profile feature of the drawing die working section (2032) are consistent with the outer structure of the target gear hub component, and cooperate with the drawing punch working section (2011) to determine the shape and size of the gear hub of the final target gear hub component.

8. The method for forming internal and external gear hub parts based on forging-bending preforming according to claim 7, characterized in that: The inner diameter of the drawing die avoidance 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.

9. A forming device for internal and external gear hub parts based on forging-bending preforming, characterized in that: It comprises a forging-bending preforming die in the internal and external gear hub part forming method based on forging-bending preforming according to any one of claims 2-8.

10. An internal and external gear hub parts forming device based on forging-bending preforming, characterized in that: It comprises a deep drawing die in the internal and external gear hub parts forming method based on forging-bending preforming according to any one of claims 1-8.

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