CN220092937U

CN220092937U - Hub forming device

Info

Publication number: CN220092937U
Application number: CN202321378865.2U
Authority: CN
Inventors: 金佩瑾
Original assignee: Ningbo Jiabijia Intelligent Technology Co ltd
Current assignee: Ningbo Jiabijia Intelligent Technology Co ltd
Priority date: 2023-06-01
Filing date: 2023-06-01
Publication date: 2023-11-28
Anticipated expiration: 2033-06-01

Abstract

The utility model relates to the technical field of hub forming, in particular to a hub forming device, which comprises a first die, a second die and a third die; the first die comprises a first upper die, a first lower die, a first ejector rod and a first cavity supporting seat; the first cavity supporting seat is hollow, and the hollow part of the first cavity supporting seat forms a first hub cavity; a first annular notch is circumferentially arranged on the outer peripheral wall of the first lower die; a first rim cavity is formed between the annular notch and the first hub cavity; a formed annular inclined surface which is inclined from top to bottom to the inside is circumferentially arranged on the inner peripheral wall of the first cavity supporting seat; the first upper die and the first lower die are matched with each other, and simultaneously cold extrusion is performed to the middle to obtain a deep cylindrical rough blank, and the rim diameter of the deep cylindrical rough blank is larger than that of the deep cylindrical rough blank through forming an annular inclined plane. The utility model has the advantages that the wheel rim is larger than the spoke, and the position fracture, fold, peeling and sundries of the wheel rim in the step of manufacturing the shape of the spoke can be avoided.

Description

Hub forming device

Technical Field

The utility model relates to the technical field of hub forming, in particular to a hub forming device.

Background

At present, the hub is manufactured in various modes, but the main manufacturing process mainly comprises casting, forging and spinning.

The casting method uses gravity or low pressure to pour alloy solution into a mould, and after forming, the alloy solution is finished by machining, surface coating and the like, and has the advantages of low cost and high production efficiency, but has the defects of incapability of eliminating defects generated by casting, easy generation of bubbles, low density, rough surface, poor comprehensive mechanical property and environmental protection.

Forging is a working method in which a metal blank is subjected to plastic deformation by pressing with a forging machine to obtain a certain shape and size. The conventional forging production is carried out under the state of metal burning, and the reliability of the product is good, but the production environment temperature is high, the danger is high, the utilization rate of the raw materials of the product is low, the material loss is high, the working procedures are more, and the subsequent processing cost is high.

The rim of the prior hub is generally smaller than the rim in the previous working procedure, so that the defects of easy foreign matter inclusion, infirm adhesion, folding, cracking and the like in the junction area can be caused.

Disclosure of Invention

The utility model aims to solve the technical problems that bubbles are easy to generate, the density is low, the surface is rough, the comprehensive mechanical property is poor and the environment is not protected in the existing hub casting process, and provides a hub forming device which enables a rim to be larger than a spoke and can avoid rim position fracture, wrinkling, skinning and sundries clamping in the spoke manufacturing step.

The utility model aims at realizing the following technical scheme:

a hub forming device comprises a first die, a second die and a third die; the first die is used for extruding the forgeable metal material to form a deep cylindrical rough blank; the second die is used for extruding the deep cylindrical rough blank to form a sub-rough blank; the third die is used for extruding the sub-rough blank to form a finished hub; the first die comprises a first upper die, a first lower die, a first ejector rod and a first cavity supporting seat; the first cavity supporting seat is hollow, and the hollow part of the first cavity supporting seat forms a first hub cavity; a first annular notch is circumferentially arranged on the outer peripheral wall of the first lower die; a first rim cavity is formed between the annular notch and the first hub cavity; a formed annular inclined surface which is inclined from top to bottom to the inside is circumferentially arranged on the inner peripheral wall of the first cavity supporting seat; the first upper die and the first lower die are matched with each other, and simultaneously cold extrusion is carried out to the middle to obtain a deep cylindrical rough blank with a protruding rim shape, and the rim diameter of the deep cylindrical rough blank is larger than that of the deep cylindrical rough blank through the forming annular inclined plane; the first ejector rod is used for ejecting the deep cylindrical rough blank from the first die. The device obtains finished hub through using the mould cold extrusion raw and other materials in whole course, and is high to the utilization ratio of material, and the qualification rate of product is also very high, produces in normal atmospheric temperature environment moreover, and the wheel hub uniformity of producing is good, and comprehensive mechanical properties is high. And can be convenient for better with the better shaping of spoke through shaping annular inclined plane, can further conveniently accomplish simultaneously to reach the rim diameter of dark tube-shape rough blank and be greater than the rim diameter of dark tube-shape rough blank, and then can avoid appearing the circumstances such as rim position fracture, fold, skinning and clamp debris in the step of preparation spoke shape, make the hub streamline of producing more smooth and easy, structural strength is high, the wholeness is good, comprehensive mechanical properties is better.

Preferably, the first ejector rod is connected to the first lower die in a lifting manner, and when ejected, the first ejector rod passes through the first lower die from bottom to top and is ejected to the deep cylindrical rough blank.

Preferably, the second die comprises a second upper die, a second lower die, a second ejector rod and a second cavity supporting seat; the second cavity supporting seat is hollow, and the hollow part of the second cavity supporting seat forms a second hub cavity; and cold extrusion is carried out through the cooperation of the second upper die and the second lower die to obtain a sub-rough blank with the required spoke shape.

Preferably, an annular step surface which is formed from top to bottom and is from outside to inside is circumferentially arranged on the inner peripheral wall of the second cavity supporting seat. The spoke is extruded at the step through the better messenger's step department of annular step face of being convenient for to be convenient for make the spoke better plastic, promote intensity and pleasing to the eye degree.

Preferably, a convex strip corresponding to the shape of the spoke is arranged on the bottom surface of the second upper die; the top surface of the second lower die is provided with a strip-shaped concave surface matched with the convex strip; a second annular notch is circumferentially arranged on the outer peripheral wall of the second lower die; a second rim cavity is formed between the second annular recess and the second hub cavity; the top of the second ejector rod is provided with an ejector rod protruding head; and combining the second upper die, the second lower die and the second ejector rod to press the deep cylindrical rough blank into a sub-rough blank containing a spoke shape. The spoke can be conveniently formed by cold extrusion through the lower pressure of the second upper die.

Preferably, the third die comprises a third upper die I, a third upper die II, a third lower die, at least two sliding blocks and a third ejector rod, wherein the sliding blocks and the third ejector rod are arranged on the side face of the third upper die II; firstly, the rim is preliminarily shaped by pressing down a third upper die I, and then the top end of the rim is formed by cold extrusion through pressing down a third upper die II, so that a finished hub in the shape of the rim is finally obtained; the third ejector rod is connected to the middle part of the third lower die in a lifting manner; and during ejection, the third ejector rod passes through the third lower die from bottom to top to the finished hub, and the finished hub is taken out. The spoke can be conveniently formed by cold extrusion through the third die.

Preferably, the top surface of the third lower die is provided with a supporting surface corresponding to the shape of the spoke; the lower part of each sliding block is provided with a sliding block step surface matched with the shape of the second die; the upper portion of slider is provided with the rim step face that is outside-in from top to bottom, and rim end shaping notch is formed at the top of rim step face, and rim step face and rim cooperate. And the rim is convenient to better mold.

Preferably, the peripheral wall of the third upper die I is provided with a rim matching surface which is arranged in the circumferential direction and is outward and inward from top to bottom; the bottom surface of the third upper die I is provided with a spoke cavity surface which is the same as the top surface of the second lower die. And the rim is convenient to better mold.

Preferably, the third upper die II is sleeved outside the third upper die I and is positioned at the upper part of the third upper die II; the bottom of the third upper die II is circumferentially provided with an annular rim end molding concave surface; the third upper die II is pressed down to enable the rim end forming concave surface to be pressed onto the rim end forming notch; and the rim end is extruded and shaped by matching the rim end molding concave surface with the rim end molding concave surface. And the top end of the rim is better formed.

Preferably, the third ejector rod is connected to the middle part of the third lower die in a lifting manner; and during ejection, the third ejector rod passes through the third lower die from bottom to top and is ejected onto the finished hub.

In summary, the utility model has the advantages that the hub has higher density, obviously improved structural strength, better surface finish of the hub, surface finish of the hub generally reaching more than 0.4, no need of reprocessing, higher structural strength and better quality; the production of the hub can greatly save raw materials, can save the step of milling the shape of the spoke on a hub blank by using processing equipment, can save equipment cost and labor cost, can not damage streamline of raw materials, can obtain better structural strength and mechanical properties, and can not generate defects such as cracks, air holes, folding or nonmetallic inclusion; the hub streamline is smoother, the structural strength is high, the integration is good, and the comprehensive mechanical property is better; the production process is few, and the hub extruded in three steps can be finished after being finished only by a small amount of finish machining, so that the production efficiency can be effectively improved, and manpower and material resources are saved.

Drawings

Fig. 1 is a schematic view of a first mold of the hub forming apparatus of the present utility model.

Fig. 2 is a plan view of a deep cylindrical blank (rim larger than spoke) according to the present utility model.

Fig. 3 is a perspective view of a deep cylindrical blank (rim larger than spoke) according to the present utility model.

Fig. 4 is a schematic view of a second mold of the hub forming apparatus of the present utility model.

Fig. 5 is a schematic view of a third die of the hub forming apparatus of the present utility model.

Fig. 6 is an exploded view of a third mold of the hub forming device of the present utility model.

Fig. 7 is a schematic view of the structure of the finished hub of the present utility model.

Fig. 8 is a structural cross-sectional view of a conventional deep cylindrical blank (rim smaller than spoke).

Fig. 9 is a schematic diagram of the formation of a streamline in the prior art extrusion-derived spoke formation process.

Wherein: 1. deep cylindrical rough blank; 101. a rim; 102. a spoke; 103. a rim; 110. a first upper die; 120. a first lower die; 130. a first ejector rod; 140. a first cavity support base; 150. forming an annular inclined plane; 170. a first annular recess; 180. a first rim cavity; 2. sub-rough blank; 210. a second upper die; 2101. a convex strip; 220. a second lower die; 2201. a strip-shaped concave surface; 2202. a second annular recess; 2203. a second rim cavity; 230. a second ejector rod; 2301. a push rod protruding head; 240. a second cavity supporting seat; 250. an annular step surface; 3. a finished hub; 310. a third upper die I; 3101. a rim mating surface; 320. a third lower die; 3201. a support surface; 330. a slide block; 3301. a slider step surface; 3302. a rim step surface; 340. a third ejector rod; 350. a third upper die II; 3501. a concave surface is formed at the end part of the rim; 3502. the end of the rim is formed with a recess.

Detailed Description

In order that the above objects, features and advantages of the utility model will be readily understood, a more particular description of the utility model will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

As shown in fig. 1 to 3, in a first step, a malleable metal material of a corresponding mass is selected according to the size and shape of the hub, and is vertically placed in a first mold composed of a first upper mold 110 and a first lower mold 120, the first lower mold 120 and the first upper mold 110 being simultaneously extruded toward the middle, and a deep cylindrical cavity including the shape of the rim 101 being extruded in a combined state. The conventional first lower die 120 and the first upper die 110 are pressed, only the first upper die 110 is pressed down, and the first lower die 120 is fixed. Therefore, the tonnage requirement of the first upper die 110 is higher, the tonnage requirement of the first upper die 110 is lower through the up-down simultaneous extrusion action, and simultaneously, the first lower die 120 and the first upper die 110 extrude the hub, so that the shaping effect is better. The wrought metal material is extruded by using the first lower die 120 and the first upper die 110 to obtain the deep cylindrical rough blank 1 comprising the shape of the rim 101, the diameter of the rim 101 of the deep cylindrical rough blank 1 is larger than that of the rim 103, and the larger rough blank of the rim 101 is processed, so that the shape of the spoke 102 is processed in the subsequent step, the possibility that streamline intersection, infirm adhesion, folding and cracking occur at the edge can be reduced due to the larger diameter of the rim 101, and the mechanical strength of a product can be improved.

As shown in fig. 1, a molded annular inclined surface 150 inclined from top to bottom from outside to inside is circumferentially provided on the inner peripheral wall of the first cavity supporting seat 140. The spoke 102 can be better molded conveniently through the molded annular inclined plane 150, the diameter of the rim 101 of the deep cylindrical rough blank 1 can be larger than that of the rim 103 of the deep cylindrical rough blank 1, and further the conditions of position fracture, fold, peeling, sundries clamping and the like of the rim 101 in the step of manufacturing the shape of the spoke 102 can be avoided, so that the produced hub streamline is smoother, high in structural strength, good in integrity and better in comprehensive mechanical property.

As shown in fig. 1, a first annular recess 170 is circumferentially provided on the outer peripheral wall of the first lower die 120; a first rim cavity 180 is formed between the first annular recess 170 and the first hub cavity; the first upper die 110 and the first lower die 120 form a deep cylindrical cavity containing the shape of the rim 101 in a combined state, the first ejector rod 130 is connected to the first lower die 120 in a lifting manner, and when ejected, the first ejector rod 130 passes through the first lower die 120 from bottom to top to be ejected onto the deep cylindrical rough blank 1. The deep cylindrical rough blank 1 is formed by the matched cold extrusion of the first upper die 110 and the first lower die 120, and the deep cylindrical rough blank 1 is conveniently ejected out by the first ejector rod 130, so that the deep cylindrical rough blank 1 is conveniently transferred to the next process.

The deep cylindrical rough blank 1 with the protruding rim 101 shape is obtained by extruding the forgeable metal material through the first die in the first step, the deep cylindrical rough blank 1 with the protruding rim 101 shape can facilitate manufacturing of the spoke 102 shape, the conditions of position fracture, fold, peeling, sundries clamping and the like of the rim 101 in the step of manufacturing the spoke 102 shape can be avoided, and the hub streamline produced by the cold extrusion hub manufacturing method is smoother, high in structural strength, good in integrity and better in comprehensive mechanical property.

As shown in fig. 4, in the second step, the deep cylindrical rough blank 1 is placed in the second lower die 220 of the second die, the bottom of the second upper die 210 of the second die is provided with a convex strip 2101 corresponding to the shape of the spoke 102, the shape of the die can be flexibly changed according to the shape of the spoke 102, the second rough blank 2 containing the shape of the spoke 102 is obtained by extrusion through the second upper die 210 and the second lower die 220, the streamline of the once formed sub rough blank 2 is smoother, the structural strength is higher, and defects such as material streamline and the like can not occur.

An annular step surface 250 which is formed from top to bottom and from outside to inside is circumferentially arranged on the inner peripheral wall of the second cavity supporting seat 240. The annular step surface 250 facilitates better extrusion of the spoke 102 at the step, so that the spoke 102 is more shaped, and strength and attractiveness are improved. The bottom surface of the second upper die 210 is provided with a convex strip 2101 corresponding to the shape of the spoke 102; the top surface of the second lower die 220 is provided with a strip-shaped concave surface 2201 matched with the convex strip 2101; a second annular recess 2202 is circumferentially provided on the outer peripheral wall of the second lower die 220; a second rim cavity 2203 is formed between the second annular recess 2202 and the second hub cavity; the top of the second ejector rod 230 of the second lower die 220 is provided with an ejector rod protruding head 2301; the deep cylindrical blank 1 is pressed into a sub-blank 2 including the shape of the spoke 102 by the combination of the second upper die 210, the second lower die 220 and the second ejector pin 230. The pressing down of the second upper die 210 facilitates the cold extrusion of the spoke 102.

As shown in fig. 5 to 6, in the third step, since the shape of the hub is basically machined in the sub-rough blank 2 stage, only the shape of the rim 103 needs to be machined in the third stage, the sub-rough blank 2 is fixed to the third lower die 320, the sub-rough blank 2 is fixed by using the slide block 330 provided on the side surface, and the third upper die ii 350 is sleeved on the third upper die i 310; the rim 103 is initially shaped by pressing down the third upper die I310, and then the end part of the rim 103 is formed by cold extrusion by pressing down the third upper die II 350, so that the finished hub 3 in the shape of the rim 103 is finally obtained. Further, in order to obtain the finished hub 3 in which the rim 103 is formed, a small amount of finish machining and surface coating such as deburring, drilling a bolt hole and the like are required.

In the third step of processing, the conventional hub is formed by spinning through a forming method and then turned, and the top end of the rim 103 is easily stressed too much in the spinning process to cause extrusion to be too thin or fracture. In the twice extrusion mode of the utility model, the lower part of the rim 103 is integrally and preliminarily shaped through the third upper die I310, and the top end of the rim 103 is extruded and molded through the third upper die II 350, so that the pressure values of the two times are different, the top end of the rim 103 is conveniently molded better, and meanwhile, the integrity and the precision requirements of the rim 103 are also ensured.

As shown in fig. 5 to 7, the top surface of the third lower die 320 is provided with a support surface 3201 corresponding to the shape of the spoke 102; the lower part of each slide block 330 is provided with a slide block step surface 3301 which is matched with the shape of the annular step surface 250; the upper part of the slide block 330 is provided with a rim step surface 3302 which is from outside to inside, the top of the rim step surface 3302 forms a rim end molding concave surface 3501, and the rim step surface 3302 is matched with the rim 103; the peripheral wall of the third upper die I310 is provided with a rim matching surface 3101 which is formed by outwards and inwards from top to bottom in the circumferential direction; the bottom surface of the third upper die i 310 is provided with the same spoke cavity surface as the top surface of the second lower die 220. The third upper die II 350 is sleeved outside the third upper die I310 and is positioned at the upper part of the third upper die II 350; the bottom of the third upper die II 350 is circumferentially provided with an annular rim end forming concave surface 3501; the third upper die ii 350 is pressed down to press the rim end forming concave surface 3501 onto the rim end forming concave recess 3502; and the rim 103 ends are extruded and shaped by the rim end forming concavities 3501 and rim end forming concavities 3502 mating. Through with second rough blank 2 back-off on the third mould to through the extrusion cooperation between third upper die I310 and the third lower mould 320, be convenient for better with rim 103 shaping, and make rim 103 outwards expand, thereby can promote joint strength and result of use. The third die further comprises a third ejector rod 340, and the third ejector rod 340 is connected to the middle part of the third lower die 320 in a lifting manner; during ejection, the third ejector rod 340 passes through the third lower die 320 from bottom to top and is ejected onto the finished hub 3. The finished hub 3 is conveniently ejected out by the lifting third ejector rod 340.

The forgeable metal material is 6061 aluminum alloy or 6082 aluminum alloy, and the aluminum alloy is a common material for hubs and has the advantages of high structural strength and the like. The aluminum alloy has small density, and the produced hub has light weight and high structural strength, is favorable for lightweight production of vehicles, and can be other alloy materials, such as wrought alloy materials meeting the requirements of hubs.

As shown in fig. 5 and 6, the number of the sliding blocks 330 may be two, the cross section of each sliding block 330 is semicircular, the sub-rough blank 2 can be well fixed by combining the two sliding blocks 330 and matching the third lower die 320, and the finished hub 3 with the shape of the rim 103 can be obtained by extruding the two sliding blocks 330 and the third upper die i 310. The number of the sliding blocks 330 can be three or more, the sub-rough blank 2 is fixed on the third lower die 320 through the matching of the three sliding blocks 330, and the shape of the rim 103 is formed by the sliding blocks 330 and the third upper die I310, so that the finished hub 3 with the shape of the rim 103 can be obtained by cold extrusion of the sub-rough blank 2 through the third upper die I310, the formation of the sliding blocks 330 can be shortened through the arrangement of the three sliding blocks 330, and the production efficiency is improved.

The ratio of the diameter of the rim 101 to the diameter of the rim 103 of the deep cylindrical rough blank 1 is 1.09-1.15, the ratio of the diameter of the rim 101 to the diameter of the rim 103 of the deep cylindrical rough blank 1 can be 1.09 or 1.15, the possibility that the streamline of the rim 101 is unreasonable in the second working procedure can be effectively reduced by reasonably setting the diameters of the rim 101 and the rim 103, the integral strength of a finished product is improved, and the deep cylindrical rough blank has good practical value.

A method of cold extruding a hub, comprising the steps of:

s1, deep cylindrical rough blank molding: putting a piece of disc-shaped malleable metal material into a first die, and extruding the disc-shaped malleable metal material into a deep cylindrical rough blank 1 with a U-shaped opening downwards by the first die in a cold extrusion process mode, wherein the upper part of the deep cylindrical rough blank 1 is a spoke 102, and the lower part of the deep cylindrical rough blank is a rim 102; and the diameter of the rim 101 of the deep cylindrical blank 1 is larger than the diameter of the rim 103 of the deep cylindrical blank 1, and finally the deep cylindrical blank 1 is taken out of the first die. The first mold comprises a first upper mold 110, a first lower mold 120, a first ejector rod 130 and a first cavity supporting seat 140; the first cavity supporting seat 140 is hollow, and the hollow part of the first cavity supporting seat 140 forms a first hub cavity; the deep cylindrical rough blank 1 with the shape of the protruding rim 101 is obtained by cold extrusion to the middle through the mutual matching of the first upper die 110 and the first lower die 120, the diameter of the rim 101 of the deep cylindrical rough blank 1 is larger than the diameter of the rim 103 of the deep cylindrical rough blank 1, and the deep cylindrical rough blank 1 is ejected from the first die through the first ejector rod 130;

s2, secondary blank molding: putting the deep cylindrical rough blank 1 into a second die, putting the deep cylindrical rough blank 1 into the second die, and extruding the deep cylindrical rough blank 1 by the second die through a cold extrusion process to obtain a secondary rough blank 2 with a required spoke shape; extruding the upper side and the lower side of the center of the spoke 102 of the sub-rough blank 2 to form spoke notches; and forming an extrusion step on the outer wall of the rim 101 of the sub-rough blank 2; the extruded sub-preform 2 is removed from the second die. The second mold comprises a second upper mold 210, a second lower mold 220, a second ejector rod 230 and a second cavity supporting seat 240; the second cavity supporting seat 240 is hollow and the hollow part of the second cavity supporting seat 240 forms a second hub cavity; cold extrusion is carried out through the cooperation of the second upper die 210 and the second lower die 220 to obtain a sub-rough blank 2 with the shape of the required spoke 102;

s3, hub molding: turning the secondary rough blank 2 for 180 degrees and placing the secondary rough blank 2 into a third die, turning the secondary rough blank 2 for 180 degrees and placing the secondary rough blank into the third die, and primarily shaping the rim 103 of the secondary rough blank 2 by the third die in a cold extrusion process mode to enable the rim 103 to be in a flaring shape; and then the top end of the rim 103 is subjected to cold extrusion and outwards bending molding, and finally the finished hub in the shape of the rim 103 is obtained. The third mold includes: the third upper die I310, the third lower die 320 and at least two sliding blocks 330 arranged on the side face, the sub-rough blank 2 is placed on the third lower die 320, the sub-rough blank 2 is fixed by using the sliding blocks 330 arranged on the side face, and the third upper die II 350 is sleeved on the third upper die I310; the rim 103 is initially shaped by pressing down the third upper die I310, and then the end part of the rim 103 is formed by cold extrusion by pressing down the third upper die II 350, so that the finished hub 3 in the shape of the rim 103 is finally obtained.

As shown in fig. 8 and 9, in the related art, the diameter of the rim 101 of the deep cylindrical rough blank 1 obtained by extrusion is equal to or smaller than the diameter of the rim 103, in the step of processing the shape of the spoke 102, the outer ring of the second die is easy to extrude the inner ring of the top of the hub when the second die extrudes the hub, so that the spoke 102 is extruded towards the rim 101, the rim 101 is thinner, and then the metal material at the rim 101 is extruded and folded. In contrast, by the diameter of the rim 101 of the deep cylindrical blank 1 being larger than the diameter of the rim 103, even if the spoke 102 is pressed to the rim 101, the junction of the spoke 102 and the rim 101 is not affected, and the overall structural strength is not affected.

The method for cold extrusion processing of the hub provided by the embodiment only needs to perform cold extrusion operation on the wrought alloy material for three times at normal temperature, and the finished hub 3 can be obtained. Compared with the conventional casting process and forging and spin-pressing process, the method for processing the hub by cold extrusion provided by the embodiment can greatly improve the production efficiency of the hub, is safe and environment-friendly in production in a normal-temperature environment, greatly saves raw materials, reduces working procedures, lowers cost, improves quality, realizes technical innovation of hub production, and has higher economic value.

Although the present disclosure is described above, the scope of protection of the present disclosure is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the scope of the utility model.

Claims

1. The hub forming device is characterized by comprising a first die, a second die and a third die;

the first die is used for extruding the forgeable metal material to form a deep cylindrical rough blank (1); the second die is used for extruding the deep cylindrical rough blank (1) to form a sub-rough blank (2); the third die is used for extruding the sub-rough blank (2) to form a finished hub (3); the first mold comprises a first upper mold (110),

A first lower die (120), a first ejector rod (130) and a first cavity supporting seat (140); the first cavity supporting seat (140) is hollow, and the hollow part of the first cavity supporting seat (140) forms a first hub cavity; a first annular recess (170) is circumferentially arranged on the outer peripheral wall of the first lower die (120); -a first rim cavity (180) is formed between the annular recess (170) and the first hub cavity; a formed annular inclined surface (150) which is inclined from top to bottom to the inside is circumferentially arranged on the inner peripheral wall of the first cavity supporting seat (140); the first upper die (110) and the first lower die (120) are matched with each other and simultaneously perform cold extrusion towards the middle to obtain a deep cylindrical rough blank (1) with a protruding rim shape, and the diameter of the rim (101) of the deep cylindrical rough blank (1) is larger than the diameter of the rim (103) of the deep cylindrical rough blank (1) through the forming annular inclined plane (150); the first ejector rod (130) is used for ejecting the deep cylindrical rough blank (1) from the first die.

2. The hub forming device according to claim 1, wherein the first ejector rod (130) is connected to the first lower die (120) in a lifting manner, and when ejected, the first ejector rod (130) passes through the first lower die (120) from bottom to top to be ejected onto the deep cylindrical rough blank (1).

3. The hub forming device according to claim 1, wherein the second mold comprises a second upper mold (210), a second lower mold (220), a second ejector pin (230) and a second cavity support (240); the second cavity supporting seat (240) is hollow, and the hollow part of the second cavity supporting seat (240) forms a second hub cavity; and (3) performing cold extrusion by mutually matching the second upper die (210) and the second lower die (220) to obtain a sub-rough blank (2) with the shape of the required spoke (102).

4. A hub forming device according to claim 3, wherein an annular step surface (250) is circumferentially arranged on the inner peripheral wall of the second cavity supporting seat (240) from top to bottom.

5. The hub forming device according to claim 3 or 4, characterized in that the bottom surface of the second upper die (210) is provided with a convex strip (2101) corresponding to the shape of the spoke (102); the top surface of the second lower die (220) is provided with a strip-shaped concave surface (2201) matched with the convex strip (2101);

a second annular recess (2202) is circumferentially arranged on the outer peripheral wall of the second lower die (220); -a second rim cavity (2203) is formed between the second annular recess (2202) and the second hub cavity; a push rod protruding head (2301) is arranged at the top of the second push rod (230); the deep cylindrical blank (1) is pressed into a sub-blank (2) comprising the shape of the spoke (102) by the combination of the second upper die (210), the second lower die (220) and the second ejector pin (230).

6. The hub forming device according to claim 1, wherein the third mold comprises a third upper mold i (310), a third upper mold ii (350), a third lower mold (320), at least two sliders (330) provided at the sides, and a third ejector pin (340), and the sub-blank (2) is placed on the third lower mold (320)

Fixing the sub-rough blank (2) by using a slide block (330) arranged on the side face, and the third upper die II

(350) Is sleeved on the third upper die I (310); firstly, the rim (103) is preliminarily shaped by pressing down a third upper die I (310), then the top end of the rim (103) is formed by cold extrusion by pressing down a third upper die II (350), and finally the finished hub (3) in the shape of the rim (103) is obtained; the third ejector rod (340) is connected to the middle part of the third lower die (320) in a lifting manner; during ejection, the third ejector rod (340)

Penetrating through the third lower die (320) from bottom to top to the finished hub (3) to push the finished hub (3)

And (5) taking out.

7. The hub forming device according to claim 6, wherein the third lower die (320)

A supporting surface (3201) corresponding to the shape of the spoke (102) is arranged on the top surface of the spoke; the lower part of each sliding block (330) is provided with a sliding block step surface (3301) matched with the shape of the second die; the upper part of the sliding block (330) is provided with a rim step surface (3302) from top to bottom, the top of the rim step surface (3302) forms a rim end forming notch (3502), and the rim step surface (3302) and the rim (103)

Matched with each other.

8. The hub forming device according to claim 6, wherein a rim matching surface (3101) which is formed from top to bottom and is outward and inward is circumferentially arranged on the outer peripheral wall of the third upper die i (310);

the bottom surface of the third upper die I (310) is provided with a spoke cavity surface which is the same as the top surface of the second lower die (220).

9. The hub forming device according to claim 6, wherein the third upper die ii (350) is sleeved outside the third upper die i (310) and is located at an upper portion of the third upper die ii (350); the bottom of the third upper die II (350) is circumferentially provided with an annular rim end molding concave surface (3501);

the third upper die II (350) is pressed down to enable the rim end forming concave surface (3501) to be pressed onto the rim end forming concave surface (3502); and the end part of the rim (103) is extruded and shaped by matching the rim end part forming concave surface (3502) with the rim end part forming concave surface (3501).

10. The hub forming device according to claim 6, wherein the third ejector rod (340) is connected to the middle part of the third lower die (320) in a lifting manner; during ejection, the third ejector rod (340)

Passes through the third lower die (320) from bottom to top and is propped against the finished hub (3).