阅读说明：本技术 一种汽车车轮的挤压成形方法及其配套组合模具 (Extrusion forming method of automobile wheel and matched combined die thereof ) 是由 杨永顺 杨茜 王少颖 方朋 于 2021-07-13 设计创作，主要内容包括：本发明公开了一种汽车车轮的挤压成形方法及其配合组合模具,该挤压成形方法是借助于一套组合模具进行的,组合模具包括锁模机构、瓣合式下模、第一压头和第二压头,锁模机构包括垫板、紧固套和驱动组件；紧固套为整体锥套结构,紧固套的内表面与镶块凹模的外表面为锥度相等的上端小下端大的锥面,紧固套下行时能够通过锥面配合将镶块凹模合模并锁紧,镶块凹模在锁模机构的驱动下能够沿直径方向产生开模与合模运动。该挤压成形方法为：在锁模状态下,第一压头下行与瓣合式下模配合挤压出不具有轮辐形状的预挤压件,第二压头下行与瓣合式下模配合挤压出具有轮辐形状的车轮制件。该成形方法能够成形出挤压轮辐形状的精密镁合金车轮精坯。(The invention discloses an extrusion forming method of automobile wheels and a matched combined die thereof, wherein the extrusion forming method is carried out by means of a set of combined die, the combined die comprises a die locking mechanism, a split type lower die, a first pressure head and a second pressure head, and the die locking mechanism comprises a base plate, a fastening sleeve and a driving assembly; the adapter sleeve is of an integral taper sleeve structure, the inner surface of the adapter sleeve and the outer surface of the insert female die are conical surfaces with the same taper, the upper end of the conical surface is small, the lower end of the conical surface is large, the insert female die can be matched and locked through conical surface matching when the adapter sleeve goes down, and the insert female die can generate die opening and die closing movement along the diameter direction under the driving of the die locking mechanism. The extrusion molding method comprises the following steps: under the mode locking state, the first pressure head descends and cooperates with the box-like lower mould of lamella to extrude the extrusion spare in advance that does not have the spoke shape, and the second pressure head descends and cooperates with the box-like lower mould of lamella and extrudes the wheel finished piece that has the spoke shape. The forming method can form the precision magnesium alloy wheel fine blank in the shape of an extruded spoke.)

1. An extrusion molding method of an automobile wheel is characterized in that: the extrusion forming method is carried out by means of a set of combined die, wherein the combined die comprises a die locking mechanism, a split type lower die, a first pressure head and a second pressure head, the first pressure head and the second pressure head can be matched with the split type lower die, the split type lower die comprises an insert female die, a die core and an ejector, the ejector is inserted into the die core in a sliding mode, and the insert female die, the die core and the ejector enclose a die cavity for forming;

the extrusion forming method comprises the following steps:

(1) and primary extrusion forming: under the mode locking state, the blank is placed into a die cavity, a first pressure head descends to be matched with a split lower die to extrude and form a pre-extrusion piece without a spoke shape, and then the first pressure head returns;

(2) and secondary extrusion forming: and the second pressure head moves downwards to be matched with the split lower die for extrusion forming to form a wheel part with a spoke shape, then the second pressure head returns, the die locking mechanism drives the insert female die to open the die, and the ejector ejects out to demould the wheel part.

2. The utility model provides a combined die for auto wheel extrusion moulding which characterized in that: the combined die comprises a die locking mechanism, a split-type lower die, a first pressure head and a second pressure head, wherein the first pressure head and the second pressure head can be matched with the split-type lower die; the split lower die comprises an insert female die, a die core and an ejector, wherein the insert female die, the die core and the ejector enclose a die cavity for forming, a first pressure head or a second pressure head is matched with the insert female die to be capable of extrusion forming, the insert female die is formed by a plurality of inserts which are distributed along the circumferential direction, and the die locking mechanism comprises a base plate horizontally and fixedly arranged on the upper surface of a lower cross beam of the hydraulic press, a fastening sleeve arranged above the base plate and a driving component for driving the fastening sleeve to move up and down; the fastening sleeve is of an integral taper sleeve structure, the inner surface of the fastening sleeve and the outer surface of the insert female die are conical surfaces with the same taper, the upper end of the conical surface is small, the lower end of the conical surface is large, the fastening sleeve is sleeved on the insert female die, and the insert female die can be matched and locked through conical surface matching when the fastening sleeve moves downwards; and a horizontal sliding guide device is arranged between each insert and the base plate, and the insert female die can generate die opening and die closing motion along the diameter direction under the driving of the die locking mechanism.

3. The combination die for extrusion molding of an automobile wheel according to claim 2, wherein: the driving assembly comprises a sleeve cylinder type combined hydraulic cylinder, the sleeve cylinder type combined hydraulic cylinder comprises a piston I fixed below the lower cross beam, a cylinder body I capable of moving up and down relative to the piston I, an oil cylinder coaxially and integrally arranged in the piston I and a piston II arranged in the oil cylinder and capable of moving up and down relative to the oil cylinder, the piston I and the cylinder body I are matched to form a driving cylinder, the oil cylinder and the piston II are matched to form an ejection cylinder, and the piston II is connected with an ejector so that the ejection cylinder can push a workpiece to be demoulded through the ejector; the end part of the cylinder body I is provided with a pulling plate, the pulling plate is vertically and fixedly connected with a plurality of pulling rods and a plurality of wedges which sequentially penetrate through the lower cross beam and the base plate and are guided by the base plate, the upper ends of the pulling rods are fixedly connected with the fastening sleeve, the number of the wedges is consistent with that of the inserts, and the upper parts of the wedges are matched with the corresponding inserts to realize the die sinking of the insert female die.

4. The combination die for extrusion molding of automobile wheels according to claim 3, wherein: each insert is provided with a wedge groove with a downward opening, the shape of the wedge groove is consistent with that of the upper part of the wedge, the side surface of the wedge groove, which is far away from the center, is an inclined surface, the upper part of each wedge is of a wedge structure, the inclination of the inclined surface of the wedge groove is the same as that of the inclined surface of the wedge, and under the action of a driving cylinder, the wedge is matched with the wedge groove to realize the die opening of the insert female die.

5. The combination die for extrusion molding of automobile wheels according to claim 4, wherein: the slope of the inner surface of the fastening sleeve is equal to the slope of the wedge.

6. The combination die for extrusion molding of an automobile wheel according to claim 2, wherein: heating devices are arranged on the split lower die, the first pressure head and the second pressure head.

Technical Field

The invention relates to the technical field of plastic forming of aluminum and magnesium alloys, in particular to an extrusion forming method of an automobile wheel and a matched combined die thereof.

Background

The magnesium alloy material has low density, high specific strength and high specific rigidity, has high shock absorption and impact resistance, and is very suitable for the use conditions of wheels. Magnesium alloy automobile wheels (hubs) have a development trend of replacing aluminum alloys to become high-end automobile wheels.

The automobile wheel mainly comprises a hub, a spoke and a rim, wherein the rim part has an undercut structure characteristic. A simple shaping method for magnesium alloy car wheel includes such steps as putting magnesium alloy blank in combined concave die, extruding, and demoulding. The method can form a wheel part without an air port, and the air port is required to be cut and processed subsequently to form a spoke part; and because the forming force is extremely large, the required mold locking force of the combined concave mold is also very large.

In the prior art, the mode locking of the combined female die mainly adopts a lateral hydraulic cylinder structure, the mode opening and closing action is flexible, but a larger hydraulic cylinder is needed, the occupied space is larger, and the female die is easy to deform to influence the product precision and generate flash due to the poor rigidity of the hydraulic cylinder; the method needs the hydraulic machine to have two downward actions, needs to be matched with a lateral hydraulic cylinder to carry out die closing and die splitting actions on the die, and certainly needs a lower ejection cylinder to carry out ejection of an extrusion piece, so that the equipment has more actions and a complex structure; the mold locking fastening sleeve is also placed at the lower part of the hydraulic machine, the four hydraulic cylinders drive the fastening sleeve to move up and down to realize the mold locking action, and because the mold needs to be installed on the workbench of the hydraulic machine, the occupied space is large, and the lateral hydraulic cylinders need to be installed, the mold locking hydraulic cylinders can only be placed at the outer side of the lower cross beam of the hydraulic machine, so that the equipment space is increased undoubtedly; and an inclined sliding block mold locking mechanism is also adopted, but the mold is complex in structure, so that the mold is used in a heating state, and the effect is poor.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides the extrusion forming method of the automobile wheel, which can form a precision magnesium alloy wheel fine blank with a spoke shape, not only can reduce the subsequent cutting processing amount and improve the material utilization rate, but also can improve the mechanical property of a product. The combined die for the wheel extrusion forming is simple and reliable in structure, small in occupied space and low in cost.

In order to achieve the purpose, the invention adopts the specific scheme that:

the extrusion forming method of the automobile wheel is carried out by means of a set of combined die, wherein the combined die comprises a die locking mechanism, a split lower die, a first pressure head and a second pressure head, the first pressure head and the second pressure head can be matched with the split lower die, the split lower die comprises an insert female die, a die core and an ejector, the ejector is inserted into the die core in a sliding mode, and the insert female die, the die core and the ejector enclose a die cavity for forming;

the extrusion forming method comprises the following steps:

(1) and primary extrusion forming: under the mode locking state, the blank is placed into a die cavity, a first pressure head descends, and is matched with a petal-type lower die to extrude to form a pre-extrusion piece without a spoke shape, and then the first pressure head returns;

(2) and secondary extrusion forming: and the second pressure head moves downwards to be matched with the petal-type lower die to extrude and form a wheel part with a spoke shape, then the second pressure head returns, the die locking mechanism drives the insert female die to open the die, and the ejector ejects out to demould the wheel part.

A combined die for extrusion molding of automobile wheels comprises a die locking mechanism, a split lower die, a first pressure head and a second pressure head, wherein the first pressure head and the second pressure head can be matched with the split lower die; the split lower die comprises an insert female die, a die core and an ejector, wherein the insert female die, the die core and the ejector enclose a die cavity for forming, and the first pressure head or the second pressure head is matched with the insert female die to be capable of performing extrusion forming; the insert female die is formed by a plurality of inserts which are distributed along the circumferential direction, and the die locking mechanism comprises a base plate which is horizontally and fixedly arranged on the upper surface of the lower cross beam of the hydraulic press, a fastening sleeve which is arranged above the base plate and a driving assembly which is used for driving the fastening sleeve to move up and down; the fastening sleeve is of an integral taper sleeve structure, the inner surface of the fastening sleeve and the outer surface of the insert female die are conical surfaces with the same taper, the upper end of the conical surface is small, the lower end of the conical surface is large, the fastening sleeve is sleeved on the insert female die, and the insert female die can be matched and locked through conical surface matching when the fastening sleeve moves downwards; and a sliding guide device is arranged between each insert and the base plate, and the insert female die can generate die opening and die closing motion along the diameter direction under the driving of the die locking mechanism.

Further, the driving assembly comprises a sleeve cylinder type combined hydraulic cylinder, the sleeve cylinder type combined hydraulic cylinder comprises a piston I fixed below the lower cross beam, an oil cylinder which can move up and down relative to the cylinder I and is coaxially and integrally arranged in the piston I, and a piston II which is arranged in the oil cylinder and can move up and down relative to the oil cylinder, the piston I and the cylinder I are matched to form a driving cylinder, the oil cylinder and the piston II are matched to form an ejection cylinder, and the piston II is connected with an ejector so that the ejection cylinder can push a workpiece to be demoulded through the ejector; the end part of the cylinder body I is provided with a pulling plate, the pulling plate is vertically and fixedly connected with a plurality of pulling rods and a plurality of wedges which sequentially penetrate through the lower cross beam and the base plate and are guided by the base plate, the upper ends of the pulling rods are fixedly connected with the fastening sleeve, the number of the wedges is consistent with that of the inserts, and the upper parts of the wedges are matched with the corresponding inserts to realize the die sinking of the insert female die.

Furthermore, each insert is provided with a wedge groove with a downward opening, the shape of the wedge groove is consistent with that of the upper part of the wedge, the side surfaces of the wedge grooves, far away from the center, are all inclined surfaces, the upper part of each wedge is of a wedge structure, far away from the center, the inclination of the inclined surface of the wedge groove is the same as that of the wedge, and under the action of the driving cylinder, the wedge is matched with the wedge groove to realize the die opening of the insert female die.

Further, the slope of the inner surface of the fastening sleeve is equal to the slope of the wedge.

Furthermore, heating devices are arranged on the split lower die, the first pressure head and the second pressure head.

Has the advantages that:

the combined die has the following advantages: 1) the mold has large mold locking force, and the mold is locked by adopting the integral fastening sleeve, so that the mold has large mold locking rigidity; the matching surface of the fastening sleeve and the insert female die has smaller inclination, and a large transverse die locking force can be generated by adopting smaller driving cylinder tension; 2) the structure is simple, the wedge structure synchronously moving with the fastening sleeve is adopted, the die opening action of the insert female die is realized, a lateral hydraulic cylinder of a die opening and closing mechanism is omitted, the die locking mechanism is simple and compact, and the occupied space of a workbench is reduced; 3) the driving cylinder and the ejection cylinder are of a combined structure, the structure is simple, the structural size is effectively reduced, and the driving cylinder and the ejection cylinder can be arranged below a lower cross beam of the hydraulic machine; 4) the piston of the driving cylinder is fixed below a lower cross beam of the hydraulic press, the cylinder body is connected with the fastening sleeve through the connecting rod, the pushing force of the driving cylinder is converted into the downward pulling force of the fastening sleeve, so that the insert female die is locked, the pushing acting force of the driving cylinder can be fully utilized, and the size of the driving cylinder is effectively reduced; and the problem that the multi-cylinder movement is asynchronous (4 driving hydraulic cylinders are adopted for driving in the prior art) is solved by avoiding adopting a plurality of hydraulic cylinders to drive the fastening sleeve to move.

Drawings

FIG. 1 is a drawing of the extrusion process of the present invention.

FIG. 2 is a schematic view showing the structure of a combined die for primary extrusion molding according to the present invention, wherein the left half is in a pre-extrusion state and the right half is in a post-extrusion state.

FIG. 3 is a schematic view showing the structure of a second combined die for extrusion molding according to the present invention, wherein the left half is in a pre-extrusion state and the right half is in a post-extrusion state.

FIG. 4 is a schematic view of the split mold in the open state after the second extrusion molding.

Graphic notation: 1. the device comprises a cylinder body I, 2, pistons I, 3, pistons II, 4, a cylinder cover, 5, an ejector, 6, a mold core, 7, a blank, 8, a first pressure head, 9, a pre-extrusion piece, 10, an insert female mold, 11, a fastening sleeve, 12, a backing plate, 13, a lower cross beam, 14, a wedge, 15, a pull rod, 16, a pulling plate, 17, a second pressure head, 18 and a wheel workpiece;

a. b, c and d are all oil passages.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to specific embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, belong to the scope of the present invention.

It should be noted that: in this specification, as shown in the drawings, downward movement of each element or part is referred to as "downward movement", and upward movement is referred to as "backward movement"; the mold takes a symmetry axis as a center, one side of each mold part close to the center is an inner side, and one side far away from the center is an outer side, wherein the radial direction refers to the horizontal direction passing through the symmetry axis of the mold; the 'insert die' refers to a die with an insert structure, the 'die opening' refers to the fact that each insert of the die moves outwards for a certain distance along the diameter direction and can be used for demolding without influencing the upward movement of a workpiece in the die, the 'die closing' refers to the fact that each insert of the die moves inwards along the diameter direction to close the insert of the die, and the 'die locking' refers to the fact that the insert of the closed die is restrained and can bear the die expanding force of an extrusion forming process on the die without being separated; the term "extrusion member" and "wheel member" refer to a member obtained by extrusion molding, and the term "pre-extrusion member" refers to a member obtained by primary extrusion molding and is a blank for secondary molding, and the pre-extrusion member is different from the extrusion member in that the spoke portion of the wheel has a disk-shaped structure and does not have a spoke (spoke) shape.

The extrusion forming method of the automobile wheel is carried out by means of a set of combined dies, wherein each combined die comprises a die locking mechanism, a split type lower die, a first pressure head 8 and a second pressure head 17, the first pressure head and the second pressure head can be matched with the split type lower die, the split type lower die comprises an insert female die 10, a die core 6 and an ejector 5, the ejector 5 is slidably inserted into the die core 6, a die cavity for forming is defined by the insert female die 10, the die core 6 and the ejector 5, and the die locking mechanism can drive the insert female die 10 to be locked or loosened;

as shown in fig. 1 to 4, the extrusion molding method includes the steps of:

(1) and primary extrusion forming: in a mode locking state, a blank 7 is placed into a die cavity, a first pressure head 8 descends, and is matched with a petal-type lower die to extrude a pre-extrusion piece 9 without a spoke shape, and then the first pressure head 8 returns;

(2) and secondary extrusion forming: and the second pressure head 17 moves downwards to be matched with the petal-type lower die to extrude and form a wheel workpiece 18 with a spoke shape, then the second pressure head 17 returns, the mold locking mechanism drives the insert female die 10 to open the mold, the ejector 5 ejects the mold, and the wheel workpiece is demoulded.

Referring to fig. 2 to 4, the combined die for extrusion molding of the automobile wheel comprises a clamping mechanism, a split lower die, a first pressing head 8 and a second pressing head 17, wherein the first pressing head and the second pressing head are matched with the split lower die; the split lower die comprises an insert female die 10, a die core 6 and an ejector 5 inserted in the die core 6 in a sliding manner, wherein the insert female die 10, the die core 6 and the ejector 5 enclose a forming die cavity, and a first pressure head 8 or a second pressure head 17 is matched with the insert female die 10 to be capable of performing extrusion forming; the insert die 10 consists of a plurality of die inserts which are distributed along the circumferential direction, and the die locking mechanism comprises a base plate 12 which is horizontally and fixedly arranged on a lower cross beam 13 of the hydraulic machine, a fastening sleeve 11 which is arranged above the base plate 12 and a driving component which is used for driving the fastening sleeve 11 to move up and down; the fastening sleeve 11 is of an annular taper sleeve structure and has high constraint strength and rigidity, the inner surface of the fastening sleeve 11 and the outer surface of the insert female die 10 are conical surfaces with the same taper, the upper end of the conical surface is small, the lower end of the conical surface is large, the fastening sleeve 11 is sleeved on the insert female die 10, and under the action of the driving assembly, the fastening sleeve 11 can match and lock the insert female die 10 through the conical surface when moving downwards. A horizontal sliding guide device (not shown in the figure) is arranged between each insert and the base plate 12, and under the action of a mold locking mechanism, the insert female mold 10 can generate mold opening and mold closing motion along the diameter direction;

the driving assembly comprises a sleeve cylinder type combined hydraulic cylinder, the sleeve cylinder type combined hydraulic cylinder comprises a piston I2 fixed below the lower cross beam 13, an oil cylinder and a piston II, the oil cylinder is coaxially and integrally arranged in the piston I and can move up and down relative to the cylinder I2, the cylinder I2 and the cylinder I1 are matched to form a driving cylinder, the oil cylinder and the piston II 3 are matched to form a jacking cylinder, and the piston II 3 is connected with the ejector 5 to push the wheel part 18 to be demoulded through the ejector 5; the end of the cylinder body I1 is provided with a pulling plate 16, the pulling plate 16 has the function of a cylinder cover and can seal and guide a driving cylinder, the pulling plate 16 is vertically and fixedly connected with a plurality of pull rods 15 and a plurality of wedges 14 which sequentially penetrate through the lower cross beam 13 and the base plate 12 and are guided by the base plate 12, the upper ends of the pull rods 15 are fixedly connected with the fastening sleeve 11, the number of the wedges 14 is consistent with that of the inserts, and the upper parts of the wedges 14 are matched with the corresponding inserts to open the die of the insert female die 10. The die insert 10 is pushed to move outwards to open the die when the wedge 14 moves upwards, and the pushing effect on the insert die 10 is released when the wedge 14 moves downwards.

Referring to fig. 2 to 4, each insert is provided with a wedge groove with a downward opening, each wedge groove has a shape conforming to the shape of the upper portion of the wedge 14, the side surfaces of the wedge grooves on the sides away from the center are all inclined surfaces, the upper portion of each wedge 14 is in a wedge structure on the side away from the center, the inclination of the inclined surface of the wedge groove is the same as that of the inclined surface of the wedge 14, and under the action of the driving cylinder, the wedge 14 and the wedge groove are matched to realize the die opening of the insert female die 10.

The cylinder body I1 drives the fastening sleeve 11 and the wedge 14 to move up and down through the pulling plate 16 and the pulling rod 15, and when the driving cylinder is pushed out downwards, a large driving force can be generated to pull the fastening sleeve 11 to move downwards, so that a large locking force is generated, and the size of the driving cylinder is small; the insert die 10 is separated through the wedge 14 during return stroke, the force required during separation is small, so that the return force of the required driving cylinder is small, the diameter of a piston I2 of the driving cylinder can be increased, the driving cylinder has enough space for the built-in ejection cylinder, and the driving cylinder and the ejection cylinder form a composite hydraulic cylinder.

In detail, referring to fig. 2, the optimized number of the insert die 10 and the wedges 14 according to the embodiment of the present invention is 4, and the optimized number of the tie bars 15 is 8.

The cushion plate 12 and the lower cross beam 13 are fixed by screws, the pull rod 15 is connected with the fastening sleeve 11 and the pull plate 16 by screws, the wedge 14 is fixedly connected with the pull plate 16 by screws, and the piston I2 is fixedly arranged on the lower cross beam 13 by screws; the pulling plate 16 is fixedly sealed with the cylinder body I1 through a sealing ring and is in guiding sealing with the piston I2 to play a role of a cylinder cover; the ejector 5 is in threaded connection with the ejection cylinder, the upper end of the ejection cylinder is guided and sealed through the cylinder cover 4, the oil paths a and b respectively connect the hydraulic system to the lower cavity and the upper cavity of the driving cylinder, and the oil paths c and d respectively connect the hydraulic system to the lower cavity and the upper cavity of the ejection cylinder.

Further, the slope of the wedge 14 is equal to the slope of the inner surface of the fastening sleeve 11.

Furthermore, heating devices are arranged on the split lower die, the first pressure head 8 and the second pressure head 17.

The foregoing is merely a preferred embodiment of the invention and is not to be construed as limiting the invention in any way. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.