CN113319599B

CN113319599B - Automobile hub machining system

Info

Publication number: CN113319599B
Application number: CN202110777578.8A
Authority: CN
Inventors: 张福建; 吴克文
Original assignee: Chongqing Chaoqun Industrial Co ltd
Current assignee: Chongqing Chaoqun Industrial Co ltd
Priority date: 2021-07-09
Filing date: 2021-07-09
Publication date: 2023-01-17
Anticipated expiration: 2041-07-09
Also published as: CN113319599A

Abstract

The invention relates to the field of hub machining, and discloses an automobile hub machining system which comprises a spoke machining unit, a rim machining unit and a welding unit for welding a rim and a spoke, wherein the rim machining unit comprises a flanging mechanism and a spinning mechanism, the spinning mechanism comprises a spinning left die, a spinning right die and a spinning knife assembly, the spinning knife assembly comprises a first spinning knife for primarily spinning the outer wall of the rim, a second spinning knife for spinning the outer wall of the rim and a wheel rim and a third spinning knife for precisely spinning the outer wall of the rim, and a spinning support member is connected between the first spinning knife and the second spinning knife; the end part of the third spinning knife is arranged to be a tip, the third spinning knife is obliquely arranged, and the inclination angle of the third spinning knife is 25-65 degrees. Compared with the traditional casting technology of the integrated wheel, the invention reduces the process difficulty of low-pressure casting, realizes low-temperature low-pressure casting, improves the mechanical property of the spoke, and can ensure good die attachment in the spinning process of the rim.

Description

Automobile hub machining system

Technical Field

The invention relates to the field of hub machining, in particular to an automobile hub machining system.

Background

The hub is a cylindrical metal part, centrally mounted on an axle, supporting the tyre by its inner profile, is an important part for supporting the weight of the vehicle, and its structural characteristics have an important influence on both the wheel and the vehicle. Existing hubs are primarily manufactured by casting or forging processes. The casting method is to pour the alloy solution into a mould by using pressure or gravity, and the alloy solution is processed and polished by a lathe after being formed. The forging method is to place the alloy block in a die and directly extrude and form the alloy block by a kiloton press. Most of the casting method and the forging method adopt the mode of integrally forming the rim and the spoke, namely, the inner part of the blank is processed to form the spoke, and the surface of the blank is processed to form the rim. The inventor finds that the integrally cast wheel is cast by the rim and the spoke together, the mold cavity structure is complex, so the requirement of the casting process on the fluidity of the molten aluminum is high, the temperature of the cast molten aluminum is forced to be high (680-720 ℃), the mold temperature is also high, and the performance of the cast casting is lower than that of the cast casting at low temperature and low pressure (645-660 ℃). Because the performance of the casting is low, the performance can be achieved only by adopting a method of adding materials under the condition of meeting the performance requirement of the whole automobile, and the performance deficiency is made up by adding materials. Therefore, the mass of the integrally cast hub is relatively large, so that the inertia resistance of the hub is large, and the hub is easily deformed and damaged during high-speed rotation. Therefore, the inventor develops a new hub processing method for respectively processing the rim and the spoke and then combining the rim and the spoke, and modifies a processing system of the hub. The principle of rim molding is as follows: the aluminum plate is formed into a cylinder after being rolled, welded and re-rounded; forming a flange at one end of the cylinder by flanging to obtain an initial shape of the flange and the edge; and spinning and forming after flanging to obtain the complete shape of the rim. In the spinning forming process of the rim, the cylinder is sleeved outside the spinning die, and then the spinning knife is used for spinning in place. However, the conventional rim spinning forming has the following problems: in the spinning process, the problem that a cylinder is not adhered to a die easily occurs to the spinning knife, so that the shape of the outer wall of the prepared rim cannot meet the requirement.

Disclosure of Invention

The invention aims to provide an automobile hub machining system, so that the defects of the existing hub machining system are overcome, the problem that a cylinder is not attached to a die in the spinning forming process of a rim is solved, and the appearance of the rim meets the requirement.

In order to achieve the purpose, the invention adopts the following technical scheme: the automobile hub machining system comprises a spoke machining unit, a rim machining unit and a welding unit for welding a rim and a spoke, wherein the rim machining unit comprises a flanging mechanism and a spinning mechanism, the spinning mechanism comprises a spinning left die, a spinning right die and a spinning knife assembly, the spinning knife assembly comprises a first spinning knife for primarily spinning the outer wall of the rim, a second spinning knife for spinning the rim of the rim and a third spinning knife for precisely spinning the outer wall of the rim, and a spinning support member is connected between the first spinning knife and the second spinning knife; the end part of the third spinning knife is arranged to be a tip, the third spinning knife is obliquely arranged, and the inclination angle of the third spinning knife is 25-65 degrees.

The principle and the advantages of the scheme are as follows: at present, the hub processing in the industry mostly adopts the traditional technology of integral casting, and has the characteristics of few working procedures and relatively low manufacturing cost. But I find that the integrally cast hub is heavy and has low performance during the process of machining the hub. In order to improve the performance of the hub and realize the light-weight design of the hub, I have conducted multi-dimensional innovative design of materials, processes and a processing system, and unfortunately increase the manufacturing cost of multiple (14) processes. Wherein spoke processing unit is used for the independent machine-shaping to the spoke, and rim processing unit is used for the independent machine-shaping to rim, when carrying out machine-shaping to rim, will prefabricate into the tip of drum through flanging mechanism and carry out the turn-ups processing, then utilize first spinning sword to carry out preliminary spinning to the drum outer wall, utilize second spinning sword to carry out spin forming to the drum outer wall and the tip after the turn-ups. Aiming at the problem that a cylinder is not adhered with a mold in the spinning forming process of a rim, the third spinning cutter is further utilized to carry out accurate spinning forming on the outer wall of the cylinder, the cutter head of the third spinning cutter is set to be pointed, the cutter head is obliquely arranged, so that the spinning contact area of the third spinning cutter is relatively small, accurate spinning can be carried out on a small arc (particularly 25-degree valve hole) without interfering or touching the rim and other parts of the mold, and the problem that the mold is not adhered in the spinning forming process of the cylinder is solved. And the welding unit is used for connecting and fixing the rim and the spoke which are respectively processed and molded to form a hub structure.

The beneficial effects of this technical scheme lie in:

1. compared with the traditional casting technology of the integrated wheel, the casting independently processed by the spoke has the advantages that the mold cavity structure is relatively simplified, so that the requirement on the fluidity of the aluminum liquid is relatively low, the fluidity of the aluminum liquid is not required to be improved by improving the temperature, the process difficulty of low-pressure casting is reduced, low-temperature low-pressure casting (645 ℃ -660 ℃) is realized, and the performance of the casting cannot be damaged due to overhigh temperature. The wheel disc and the wheel rim which are separately prepared have better mechanical properties (tensile strength, yield strength and elongation percentage) than the traditional integrated wheel. And the newly developed wheel only needs to develop a low-pressure casting die of the spoke part, can be flexibly combined with the rim, greatly shortens the development period, is suitable for batch production and has high efficiency.

2. Because the spoke and the rim are separately processed, the wheel can be cast at low temperature and low pressure, and therefore, the mechanical performance of the wheel hub is not required to be improved by adding materials like the prior art, and the light weight design of the wheel hub is realized. Through detection, compared with the integrated wheel processing, the process of welding and fixing the spoke and the rim after being processed independently not only improves the mechanical property of the wheel hub, but also reduces the whole weight by 20-30% compared with the traditional integrated wheel, and realizes the light weight design of the wheel. The wheel lightweight design has the following benefits on the whole vehicle: (1) the weight of the whole vehicle is reduced, and the endurance mileage is increased by more than 6%; (2) the starting acceleration of 0-100Km/h is improved by 0.15-0.25 second; (3) the braking distance of 100-0Km/h is shortened by 1-3m; (4) the steering is clear, and the control performance is improved.

3. In the technical scheme, the spinning cutter assembly is optimized in structure, wherein the first spinning cutter moves axially along the rim and is used for carrying out primary spinning on the outer wall of the rim; the second spinning cutter is used for spinning the flanging position of the rim to form the rim; the third spinning cutter is used for carrying out accurate spinning forming on the outer wall of the rim, and the cutter head of the third spinning cutter is arranged to be the tip end and is obliquely arranged, so that accurate spinning can be carried out on a small circular arc (particularly at a 25-degree valve hole) without interfering or touching the rim and other parts of the die. The problem that the cylinder is not attached to the die in the spinning forming process of the rim is solved.

Preferably, as an improvement, turn-ups mechanism includes mould and lower mould, and the lower extreme of going up the mould is provided with slope guide part and circular arc groove, and the top and the circular arc groove of slope guide part link up, and the slope guide part leans out the setting, and the diameter of the bottom of slope guide part is less than the internal diameter of drum.

In the technical scheme, the upper die and the lower die are matched to be used for flanging the end part of the cylinder, the inclined guide part on the upper die is utilized to guide the top end of the cylinder, so that the top end of the cylinder moves along the inclined guide part and enters the arc groove, the flaring and the flanging on the top end of the cylinder are realized, the flaring and the flanging on the top end of the cylinder are finished on the same die at one time, the working efficiency is improved, and the workload of workers is reduced. The lower die is used for fixing/expanding the cylinder to be processed.

Preferably, as a modification, the inclination angle of the inclined guide part is 4 ° to 6 °, and the radius of the circular arc groove is 16 to 22mm.

In the technical scheme, the inventor finds that when the inclination angle of the inclined guide part is 4-6 degrees and the radius of the arc groove is 16-22mm, smooth molding of the cylinder can be ensured, otherwise, the problems of drum turning and flanging failure can occur.

Preferably, as an improvement, the upper part of the lower die is provided with a containing groove for containing the upper die, a chamfer is arranged between the bottom of the containing groove and the outer wall of the lower die, and the angle range of the chamfer is 9-11 degrees.

Among this technical scheme, when using, go up mould and lower mould and cooperate the use, go up mould, can relative motion between the lower mould, the setting of holding tank can hold the mould and can standardize the removal route of going up the mould simultaneously, the setting of chamfer can be treated placing of processing drum and play the effect of direction, the inventor finds through many times of experiments, when the inclination of chamfer was 9-11, can fine direction treat that the processing drum moves down along the lower mould.

Preferably, as an improvement, the lower extreme of going up the mould is provided with the hangers, and the hangers includes vertical portion and horizontal part, and vertical portion is connected with last mould, and the horizontal part can offset with the turn-ups of waiting to process the drum.

In the technical scheme, the hanging lug is positioned below the turned edge formed after the turned edge at the top end of the cylinder, after the turned edge of the cylinder is machined, the upper die moves upwards and resets relative to the lower die, and the turned edge at the top end of the cylinder is hooked on the horizontal part of the hanging lug so as to lift the cylinder upwards, so that the cylinder is separated from the lower die, and the cylinder after the turned edge is conveniently taken down by a worker.

Preferably, as an improvement, the outer wall of the spinning left die is set to be a curved surface, one end of the spinning right die, which is far away from the spinning left die, is provided with a pressing plate and a connecting piece, the pressing plate is provided with a through hole for the connecting piece to penetrate through, the pressing plate is connected with the connecting piece in a sliding manner, and one end of the pressing plate, which faces the spinning left die, is provided with a limiting groove for the end part of the cylinder to be processed to extend into; one end of the connecting piece, which is far away from the right die, is connected with a fixed plate, and an elastic piece used for pre-tightening the pressing plate is arranged between the pressing plate and the fixed plate.

When the cylindrical tube is subjected to spinning forming, the wall thickness of a part of the cylindrical tube is thinned by the spinning knife assembly, and the cylindrical tube is expanded in the axial direction. In the technical scheme, the spinning left die and the spinning right die are matched to limit and fix the flanged cylinder. Utilize the connecting piece and locate the elastic component on the connecting piece for the clamp plate can take place to slide along the axial of connecting piece relatively right mould, so that the clamp plate adaptability slides when taking place to extend in drum spin forming process, simultaneously, utilize the spacing groove on the clamp plate to carry on spacingly to the right-hand member of drum, avoid the right-hand member of drum to take place the warpage, avoid the expansion of the right-hand member mouth of drum promptly, prevent the problem that finished product rim can't form wheel hub with the spoke complex. Moreover, because the pressing plate is subjected to the pre-tightening action of the elastic piece, the pressing plate can apply clamping force to the end part of the cylinder in the cylinder spinning forming process, so that the cylinder is always fixed on the left die and the right die, and the spinning cutter assembly is convenient to spin the cylinder.

Preferably, as a modification, the elastic member is a support spring, and the support spring is sleeved outside the connecting member.

Among this technical scheme, supporting spring can overlap the outside of establishing at the connecting piece for the elastic component is located between clamp plate and the fixed plate, compares in the connected mode of fixing the elastic component between clamp plate and fixed plate, and the connection structure of this scheme is more convenient dismantlement, change and maintenance.

Preferably, as an improvement, one end of the spinning right die, which is far away from the spinning left die, is provided with a first guide part, the pressing plate is provided with a guide hole in sliding fit with the first guide part, the spinning right die and the guide part are concentrically arranged, and the pressing plate and the guide hole are concentrically arranged.

In the technical scheme, the pressing plate slides along the first guide part of the spinning right die, so that the sliding of the pressing plate is guided, the moving path of the pressing plate is normalized, and the pressing plate is prevented from moving in the radial direction of the spinning right die.

Preferably, as an improvement, one end of the spinning right die, which is close to the spinning left die, is provided with a second guide part, the spinning left die is provided with a guide groove for accommodating the second guide part, the second guide part and the spinning right die are arranged concentrically, and the guide groove and the spinning left die are arranged concentrically; one end of the spinning left die, which is far away from the spinning right die, is provided with an arc-shaped limiting arc for accommodating a flanging of a cylinder to be processed.

In the technical scheme, the second guide part is in sliding fit with the guide groove to guide the moving path of the spinning right die, so that the spinning right die and the spinning left die are concentric, and the outer contour of the spinning left die and the spinning right die after combination is matched with the shape of a finished rim. In addition, the end part of the spinning left die is provided with the limiting arc, so that the curled edge of the cylinder after flanging can be limited.

Preferably, as an improvement, the welding unit comprises a welding rack, a friction stir welding machine body, a supporting tool and a friction stir welding head, the supporting tool is rotationally connected to the welding rack, the friction stir welding machine body is arranged on one side of the supporting tool, the friction stir welding head is rotationally connected to the friction stir welding machine body, the friction stir welding head comprises a welding head body and a welding needle, and two rings of grooves which are concentrically arranged are arranged at the end part of the welding head body; the welding needle is fixed on the welding head body, and sets up with the recess is concentric, and the main aspects of welding needle are provided with first screw thread portion, and the tip of welding needle is provided with second screw thread portion, and first screw thread portion revolves to opposite with second screw thread portion, and the diameter of welding needle main aspects is greater than the diameter of welding needle tip, and the diameter of welding needle main aspects does: phi 5.8-7.8, the diameter of the small end of the welding pin is as follows: phi is 3.5 to 4.5; the height of the supporting tool and the radial runout of the circumference after being unfolded are both less than or equal to 0.1mm, and the gap at the composite position of the rim and the spoke is less than or equal to 0.3mm.

In the technical scheme, after the rim and the spoke are respectively processed and formed, the welding unit is utilized to realize the welding fixation of the rim and the spoke. During welding, the rim and the spoke are welded and fixed through high-speed rotation of the friction stir welding head, welding flux is not needed, and the machined hub is excellent in mechanical performance. In addition, the technical scheme also optimizes the structure of the friction stir welding head, wherein the groove is used for accommodating and sealing plasticized materials generated by pressing the shaft shoulder into the surface of the part, so that the materials are prevented from overflowing; by arranging the positive and negative threads on the welding needle, the stirring amplitude can be increased when a welding seam is inserted for use, and the welding effect is ensured; and the service life of the welding needle can be prolonged by thickening the diameter of the welding needle. In addition, among this technical scheme, the big end diameter of welding pin, tip diameter and the gap width of rim and spoke complex department have been optimized and have been injectd, verify through actual processing, and the diameter of welding pin and the clearance width cooperation between rim and the spoke are the most reasonable among this technical scheme, can avoid welding defect, like welding department mechanical properties is bad, welding defects such as cavity type, tunnel type. If the diameter of the welding pin is not within the above range, or if the width of the gap is greater than 0.3mm, hub quality problems may be caused, such as: early failure, air leakage of light persons and cracking of the welding part of the rim and the spoke of heavy persons occur.

Drawings

Fig. 1 is a front longitudinal sectional view of a flanging mechanism according to an embodiment of the present invention.

Fig. 2 is an enlarged view of a point A1 in fig. 1.

Fig. 3 is a front longitudinal sectional view of a matched flanging state of an upper die and a lower die in an embodiment of the invention.

Fig. 4 is a front longitudinal sectional view of an upper die and a lower die in a matched flanging state in the second embodiment of the present invention.

Fig. 5 is a front longitudinal sectional view of a spinning mechanism according to an embodiment of the present invention.

Fig. 6 is a front longitudinal sectional view of a state where the first spinning blade, the second spinning blade and the spinning right die are engaged according to the first embodiment of the present invention.

Fig. 7 is a front longitudinal sectional view showing a state where a third spinning blade is engaged with a spinning left die according to a first embodiment of the present invention.

FIG. 8 is a front longitudinal cross-sectional view of the formed rim.

Fig. 9 is a front view of a friction stir welding head according to one embodiment of the present invention.

Fig. 10 is an isometric view of a friction stir weld head in accordance with a first embodiment of the present invention.

Fig. 11 is a schematic structural view of a spoke and rim combination in the first embodiment of the invention.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: the device comprises an upper die holder 1, an upper die body 2, an inclined guide part 3, an arc groove 4, a lower die holder 5, a lower die body 6, a containing groove 7, a chamfer 8, a gasket 9, a spinning left die 10, a spinning right die 11, a first spinning knife 12, a second spinning knife 13, a pressing plate 14, a connecting piece 15, a limiting groove 16, a fixing plate 17, an elastic piece 18, a first guide part 19, a guide hole 20, a second guide part 21, a guide groove 22, a limiting arc 23, a cylinder 24, a processing-molded rim 25, a hanging lug 26, a vertical part 27, a horizontal part 28, a third spinning knife 29, a tip 30, a welding head body 31, a welding needle 32, a groove 33 and a buffer space 34.

Example one

This embodiment is substantially as shown in figures 1-7 of the drawings: the automobile hub machining system comprises a spoke machining unit, a rim machining unit and a welding unit.

The spoke processing unit is used for processing and forming spokes and is completed by adopting a low-temperature and low-pressure casting process, and the specific process refers to the patent of the invention: CN110560664A casting and pouring method and application thereof, casting method of automobile wheel and automobile wheel.

The rim processing unit is used for processing the rim and comprises a flanging mechanism and a spinning mechanism.

As shown in fig. 1 to 4, the flanging mechanism is used for flanging the end of the preformed cylinder 24, and the flanging mechanism includes an upper die and a lower die, where the upper die includes an upper die base 1 and an upper die body 2, and the upper die body 2 is fixed at the bottom of the upper die base 1 by bolts. The bottom of the upper die body 2 is provided with an inclined guide part 3 and an arc groove 4, the top end of the inclined guide part 3 is arranged in an outward inclined manner, the inclined angle of the inclined guide part 3 is 4-6 degrees, and the inclined angle of the inclined guide part 3 in the embodiment is 6 degrees. The top of slope guide part 3 links up with circular arc groove 4, and the radius of circular arc groove 4 is 16-22mm, and the radius of circular arc groove 4 is 22mm in this embodiment. The bottom end diameter of the inclined guide portion 3 is smaller than the inner diameter of the cylinder 24 to be processed.

The lower die is detachably connected to the upper die, and the lower die is matched with the upper die for use. The lower die comprises a lower die base 5 and a lower die body 6, and the lower die body 6 is fixed at the top end of the lower die base 5 through a bolt. Lower die body 6 is used for fixed drum 24, and the concrete mode is inner wall interference fit or transition fit of lower die body 6 and drum 24, and the upper portion of lower die body 6 is provided with holding tank 7, and holding tank 7 forms the echelonment structure with lower die body 6, is provided with chamfer 8 between the bottom of holding tank 7 and the outer wall of lower die body 6 to in waiting to process smooth uide bushing of drum 24 and establish outside die body 6 down, chamfer 8's angular range is 9-11, chamfer 8's angle in this embodiment is 11. The periphery of the bottom of the lower die body 6 is sleeved with a gasket 9, and the gasket 9 is fixed on the lower die seat 5 through a bolt.

As shown in fig. 5-7, the spinning mechanism is used for spinning the flanged cylinder 24, and the spinning mechanism includes a spinning left die 10, a spinning right die 11 and a spinning knife assembly. The spinning knife assembly comprises a first spinning knife 12 for primarily spinning the outer wall of the rim to be processed, a second spinning knife 13 for spinning the rim of the rim and a third spinning knife 29 for finely spinning the outer wall of the rim, a spinning support member is connected between the first spinning knife 12 and the second spinning knife 13, and the diameter of the first spinning knife 12 is larger than that of the second spinning knife 13; the end of the third spinning blade 29 is set to be a tip 30, and the third spinning blade 29 is obliquely set, and the inclination angle of the third spinning blade 29 is 60 °.

Spinning left side mould 10 uses with the cooperation of spinning right side mould 11, the right-hand member of spinning right side mould 11 is provided with clamp plate 14 and connecting piece 15, the recess that the right-hand member that supplies spinning right side mould 11 is absorbed in is seted up to the left side wall of clamp plate 14, set up the through-hole that supplies connecting piece 15 to run through on the clamp plate 14, clamp plate 14 is equipped with the spacing groove 16 that the tip that supplies to process drum 24 stretches into towards the one end of spinning left side mould 10, spacing groove 16 is the annular, the inboard cell wall slope of spacing groove 16 sets up, the notch internal diameter of spacing groove 16 is greater than the tank bottom internal diameter of spacing groove 16 promptly, so that the right-hand member of drum 24 can stretch into spacing groove 16 by the notch of spacing groove 16 easily. The connecting pieces 15 in this embodiment are screws, the number of the connecting pieces 15 is two, the connecting pieces 15 are transversely arranged, the left end of each connecting piece 15 penetrates through the pressing plate 14 and is fixed on the spinning right die 11, and the right end of each connecting piece 15 is fixed with the fixing plate 17. An elastic part 18 is arranged between the pressing plate 14 and the fixing plate 17, the elastic part 18 in this embodiment is a supporting spring, the supporting spring is sleeved outside the connecting part 15, the supporting spring respectively abuts against the pressing plate 14 and the fixing plate 17, and the pre-pressure of the supporting spring is 400N. A first guide part 19 is integrally formed at the right end of the spinning right die 11, a guide hole 20 in sliding fit with the first guide part 19 is formed in the pressing plate 14, the spinning right die 11 and the first guide part 19 are concentrically arranged, and the pressing plate 14 and the guide hole 20 are concentrically arranged. Thus, the pressing plate 14 is ensured to be concentric with the spinning right die 11, and the pressing plate 14 is ensured to be concentric with the spinning right die 11 all the time in the axial sliding process of the spinning right die 11. The left end of the spinning right die 11 is integrally formed with a second guide part 21, the right end of the spinning left die 10 is provided with a guide groove 22 in sliding fit with the second guide part 21, the second guide part 21 and the spinning right die 11 are arranged concentrically, and the guide groove 22 and the spinning left die 10 are arranged concentrically. Therefore, the spinning right die 11 and the spinning left die 10 are ensured to be concentric, and the spinning right die 11 can be always concentric with the spinning left die 10 in the leftward movement process, so that the outer contour formed after the spinning right die 11 and the spinning left die 10 are combined is ensured to be matched with the overall shape of a finished rim. The outer wall of the spinning left die 10 is set to be a curved surface, and an arc-shaped limiting arc 23 used for accommodating the flanging of the cylinder 24 to be processed is arranged at one end, far away from the spinning right die 11, of the spinning left die 10.

The welding unit is used for welding and fixing the independently processed rim and the spoke, and comprises a welding rack, a friction stir welding machine body, a supporting tool and a friction stir welding head. The supporting tool comprises a circular table and an inner support, the circular table is connected to the welding rack in a rotating mode, the inner support is used for supporting the connecting portion of the rim and the spoke, and the connecting portion has a movement trend of expanding outwards in the radial direction of the spoke. The friction stir welding machine body is fixed on the welding frame through bolts, the friction stir welding head is rotatably connected to the friction stir welding machine body, the friction stir welding head is used for welding a rim and a spoke together (not shown in the figure), the friction stir welding head comprises a welding head body 31 and a welding needle 32, and two circles of grooves 33 which are concentrically arranged are arranged at the end part of the welding head body 31, as shown in fig. 9 and 10; the welding needle 32 is fixed on the welding head body 31, and with recess 33 concentric arrangement, the front end of welding needle 32 is provided with first screw thread portion, the rear end of welding needle 32 is provided with second screw thread portion, first screw thread portion is opposite with second screw thread portion soon, the diameter of welding needle 32 front end (left end) is greater than the diameter of welding needle 32 rear end (right-hand member), the diameter of welding needle 32 increases gradually along its direction towards the welding head body 31 promptly, the diameter of welding needle 32 front end is: phi 5.8-7.8, the diameter of the rear end of the welding pin 32 is as follows: phi 3.5-phi 4.5. The height of the supporting tool and the radial runout of the circumference after being unfolded are both less than or equal to 0.1mm, and the gap at the composite position of the rim and the spoke is less than or equal to 0.3mm.

The specific implementation process is as follows:

1. machining and forming of spoke

The method is characterized in that an aluminum ingot is smelted, refined and degassed, and then cast and molded by an electric die casting mold, wherein the casting and molding process is low-temperature low-pressure casting, and the specific process refers to the patent of the invention: CN110560664A casting and pouring method and application thereof, casting method of automobile wheel and automobile wheel, then solid solution heat treatment, aging heat treatment and automobile composite opening are carried out in sequence, and the parts are prior art and are not described herein.

2. Machining and forming of wheel rim

An aluminum plate (O-state 6061 aluminum plate with copper content of 0.2-0.3%) is cut, rolled and flattened, and then prefabricated into a cylinder 24 by friction stir welding.

And then, flanging the cylinder 24, specifically, sleeving the cylinder 24 to be flanged on the outer part of the lower die body 6, wherein the chamfer 8 plays a guiding role in the process. Due to the interference fit between the lower die body 6 and the cylinder 24, the cylinder 24 can be stably connected to the outside of the lower die body 6. Then, the upper die body 2 is driven by a driving part (which can be a part performing linear reciprocating motion such as an air cylinder, a hydraulic cylinder, etc.) to move downwards, so that the inclined guide part 3 is inserted into the accommodating groove 7, the outer wall of the inclined guide part 3 is accommodated in the cylinder 24, and along with the downward movement of the lower die body 6, the inclined guide part 3 applies an outward extrusion force to the top end of the cylinder 24, so that the top end of the cylinder 24 is expanded outwards, and thus, the flaring process of the top end of the cylinder 24 is realized.

The upper die body 2 continues to move downwards, and a holding force is generated between the inclined guide part 3 and the inner peripheral wall of the top end of the cylinder 24, so that the cylinder 24 moves downwards along the lower die body 6 until the bottom end of the cylinder 24 abuts against the gasket 9, and the cylinder 24 does not move downwards any more; and as the upper die body 2 continues to move downwards, the top end of the cylinder 24 moves into the arc groove 4 along the inclined guide part 3, and the top end of the cylinder 24 is curled along the arc groove 4, so that the flanging of the top end of the cylinder 24 is realized. After the flanging at the top end of the cylinder 24 is completed, the upper die body 2 is driven by the driving piece to move upwards for resetting, and a worker takes down the cylinder 24 on the lower die body 6, which is subjected to flanging.

Then, spinning the flanged cylinder 24, placing the flanged cylinder 24 on the spinning left die 10 by a worker, and positioning the left end of the cylinder 24 on a corresponding part of the spinning left die 10; subsequently, the spinning right die 11 is moved leftward by the driving of the driving member until the spinning right die 11 is combined with the spinning left die 10. In the process, the second guiding part 21 on the spinning right die 11 gradually enters the guiding groove 22 of the spinning left die 10, and the outer peripheral wall of the second guiding part 21 is in contact with the inner peripheral wall of the guiding groove 22, so that the spinning right die 11 and the spinning left die 10 are concentric. With the continuous leftward movement of the spinning right die 11, the outer peripheral wall of the spinning right die 11 extends into the right end of the cylinder 24, the outer peripheral wall of the spinning right die 11 is in contact with the inner peripheral wall of the cylinder 24 until the right end of the cylinder 24 extends into the limiting groove 16 on the pressing plate 14, the right end of the cylinder 24 abuts against the groove wall of the limiting groove 16, the supporting spring applies elasticity to the pressing plate 14, so that the pressing plate 14 applies a pretightening force to the cylinder 24, and the cylinder 24 is fixed on the combined spinning left die 10 and the spinning right die 11.

Then, the spinning left die 10 and the spinning right die 11 rotate, and the first spinning knife 12 moves axially along the cylinder 24 and is used for carrying out primary spinning on the outer wall of the cylinder 24; the second spinning knife 13 is used for spinning the flanging position of the cylinder 24 to form a wheel rim; the third spinning knife 29 is used for performing accurate spinning forming on the outer wall of the cylinder 24, and the tool bit of the third spinning knife 29 is set to be the tip 30 and is obliquely arranged, so that accurate spinning can be performed on the small arc without interfering or touching other parts of the rim and the die. The part of the cylinder 24 acted by the first spinning knife 12 is deformed, the wall thickness is thinned, the right end of the cylinder 24 is extended and lengthened (the left end of the cylinder 24 is limited by the corresponding part of the spinning left die 10 and cannot move), at the moment, the pressure plate 14 is acted leftwards, and the first guide part 19 of the spinning right die 11 is in sliding fit with the guide hole 20 of the pressure plate 14, so that the pressure plate 14 moves rightwards to compress a supporting spring, the pressure plate 14 keeps concentric with the spinning right die 11 in the process of moving rightwards to adapt to the extended length of the cylinder 24, meanwhile, the pressure plate 14 always exerts a reaction force on the right end of the cylinder 24, and the cylinder 24 is fixed on the combined spinning left die 10 and spinning right die 11, so that the first spinning knife 12 and the second spinning knife 13 perform spinning operation.

In the process, when the right end of the cylinder 24 extends rightwards, the right end of the cylinder 24 is located in the limiting groove 16 of the pressing plate 14, so that a right port of the cylinder 24 cannot be expanded outwards, the inner diameter of the port of the finished rim meets the processing requirement, and the finished rim and the spoke can be compounded to form the hub. After spinning is finished, the spinning right die 11 moves rightwards under the action of the driving piece, the spinning right die 11 is separated from the spinning left die 10, and a worker takes down a finished rim after spinning forming. The structure of the formed rim 25 is shown in fig. 8.

3. Rim to spoke welding

Install rim and spoke on the round platform, the internal stay is used for supporting the junction of rim and spoke, makes the radial outside expansion of spoke and offsets with the rim, then starts friction stir welding machine body for the friction stir welding head is to the junction circumference welded fastening of rim and spoke. The groove 33 is used for accommodating and sealing plasticized materials generated by pressing the shaft shoulder into the surface of the part, so that the materials are prevented from overflowing; by arranging the positive and negative threads on the welding needle 32, the stirring amplitude can be increased when the welding needle is inserted into a welding seam for use, and the welding effect is ensured; moreover, the service life of the welding pin 32 can be prolonged by thickening the diameter of the welding pin.

Compared with the traditional casting technology of the integrated wheel, the invention reduces the process difficulty of low-pressure casting, realizes low-temperature low-pressure casting at 645-660 ℃, has better mechanical properties (tensile strength, yield strength and elongation percentage) of the spoke than the traditional integrated wheel, only needs to develop a low-pressure casting mold of the spoke part of the newly developed wheel, can be flexibly combined with the rim, and greatly shortens the development period. In addition, according to the scheme, through the structural optimization of the spinning cutter assembly, when the inclination angle of the third spinning cutter 29 in the spinning forming step is limited to 60 degrees, the mold attaching degree of the rim is high, the forming is good, and particularly the mold attaching degree of a 25-degree angle where a valve hole is located is high.

Example two

As shown in fig. 4, the present embodiment is different from the first embodiment in that: in this embodiment, a hanging lug 26 is provided at the lower end of the upper die, the hanging lug 26 includes a vertical portion 27 and a horizontal portion 28, the vertical portion 27 is fixed to the upper die by a bolt, and the horizontal portion 28 can abut against a flange of the cylinder 24 to be processed.

In use, when the top end of the barrel 24 is flanged, the flange formed by flanging the top end of the barrel 24 is positioned above the horizontal portion 28 of the hanger 26. When the upper die body 2 is driven by the driving member to move upwards for resetting, the curled edge at the top end of the cylinder 24 is hooked on the horizontal part 28 of the hanging lug 26, so that the cylinder 24 is lifted upwards, the cylinder 24 is separated from the lower die, a worker can conveniently take down the flanged cylinder 24, and the working efficiency is improved compared with the process that the worker manually takes down the flanged cylinder 24 from the lower die body 6.

EXAMPLE III

The difference between the present embodiment and the first embodiment is: the inclination angle of the third spinning blade 29 in this embodiment is 25 °.

Example four

The difference between the present embodiment and the first embodiment is: the inclination angle of the third spinning blade 29 in this embodiment is 65 °.

Comparative example 1

The comparative example differs from the first example in that: the hub is manufactured by adopting the traditional integral wheel casting process, namely, the integral low-pressure casting process of the spoke and the rim is adopted.

Comparative example No. two

The comparative example differs from the first example in that: the inclination angle of the third spinning blade 29 is 20 °.

Comparative example No. three

The comparative example differs from the first example in that: the inclination angle of the third spinning blade 29 is 70 °.

The hubs prepared in examples one to four and comparative examples one to three were subjected to performance tests, wherein the tensile strength, yield strength and elongation tensile tests were carried out in accordance with GB/T228-2010, and the results are shown in Table 1.

TABLE 1

As can be seen from table 1, the mechanical properties (tensile strength, yield strength and elongation) of the hub manufactured by the present invention are superior to those of the hub manufactured by the conventional one-piece wheel casting process. In addition, in the invention, the inclination angle of the third spinning cutter in the spinning forming step is limited to 25-65 degrees, and the spinning process of the cylinder is improved, so that the rim has high attaching degree and good forming, and particularly the attaching degree of the valve hole at the angle of 25 degrees is high. In addition, the wall thickness of the rim is appropriate, and the rim is well formed.

Moreover, the wheel hub is formed by welding the rim and the spoke by a friction stir welding process, and compared with the method of fixedly connecting the rim and the spoke through bolts or fixedly connecting the rim and the spoke through riveting, the wheel hub can reduce the weight of the wheel hub and ensure the air tightness of the rim (most of tires in the prior art need tubeless tires, and the rim part needs good air tightness). Moreover, the hub manufactured in the present invention has the buffer space 34 (shown in fig. 11), the buffer space 34 can well reduce the impact force received by the hub from the radial direction and the axial direction of the hub, and more obviously, the buffer space 34 can reduce the influence of the impact force from the axial direction of the hub on the rim, thereby ensuring the structural stability of the hub, especially the rim.

The above description is only an example of the present invention, and the general knowledge of the known specific technical solutions and/or characteristics and the like in the solutions is not described herein too much. It should be noted that, for those skilled in the art, without departing from the technical solution of the present invention, several variations and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. Automobile wheel hub system of processing, its characterized in that: the wheel rim machining unit comprises a flanging mechanism and a spinning mechanism, the spinning mechanism comprises a spinning left die, a spinning right die and a spinning knife assembly, the spinning knife assembly comprises a first spinning knife for primarily spinning the outer wall of the wheel rim, a second spinning knife for spinning the wheel rim of the wheel rim and a third spinning knife for precisely spinning the outer wall of the wheel rim, and a spinning support member is connected between the first spinning knife and the second spinning knife; the end part of the third spinning knife is arranged to be a tip, the third spinning knife is obliquely arranged, and the inclination angle of the third spinning knife is 25-65 degrees; the outer wall of the spinning left die is set to be a curved surface, one end of the spinning right die, which is far away from the spinning left die, is provided with a pressing plate and a connecting piece, the pressing plate is provided with a through hole for the connecting piece to penetrate through, the pressing plate is connected with the connecting piece in a sliding manner, and one end of the pressing plate, which faces the spinning left die, is provided with a limiting groove for the end part of the cylinder to be processed to stretch into; one end of the connecting piece, which is far away from the right die, is connected with a fixed plate, and an elastic piece for pre-tightening the pressing plate is arranged between the pressing plate and the fixed plate; the flanging mechanism comprises an upper die and a lower die, the lower end of the upper die is provided with an inclined guide part and an arc groove, the top end of the inclined guide part is connected with the arc groove, the inclined guide part is arranged in an outward inclined manner, and the diameter of the bottom end of the inclined guide part is smaller than the inner diameter of the cylinder; the inclination angle of the inclined guide part is 4-6 degrees, and the radius of the arc groove is 16-22mm; the lower extreme of going up the mould is provided with the hangers, and the hangers includes vertical portion and horizontal part, and vertical portion passes through bolted connection with last mould to be fixed, and the horizontal part can offset with the turn-ups of waiting to process the drum.

2. The automobile hub machining system according to claim 1, characterized in that: the upper portion of lower mould is provided with the holding tank that is used for holding the mould, is provided with the chamfer between the outer wall of bottom and the lower mould of holding tank, and the angle range of chamfer is 9-11.

3. The automobile hub machining system according to claim 2, characterized in that: the elastic part is a supporting spring which is sleeved outside the connecting part.

4. The automobile hub machining system according to claim 3, characterized in that: one end, far away from the spinning left die, of the spinning right die is provided with a first guide portion, the pressing plate is provided with a guide hole in sliding fit with the first guide portion, the spinning right die and the guide portion are arranged concentrically, and the pressing plate and the guide hole are arranged concentrically.

5. The automobile hub machining system according to claim 4, characterized in that: one end, close to the spinning left die, of the spinning right die is provided with a second guide portion, a guide groove used for containing the second guide portion is formed in the spinning left die, the second guide portion and the spinning right die are arranged concentrically, and the guide groove and the spinning left die are arranged concentrically; and one end of the spinning left die, which is far away from the spinning right die, is provided with an arc-shaped limiting arc for accommodating a flanging of the cylinder to be processed.

6. The automobile hub machining system according to claim 5, characterized in that: the welding unit comprises a welding rack, a friction stir welding machine body, a supporting tool and a friction stir welding head, the supporting tool is rotationally connected to the welding rack, the friction stir welding machine body is arranged on one side of the supporting tool, the friction stir welding head is rotationally connected to the friction stir welding machine body, the friction stir welding head comprises a welding head body and a welding needle, and two circles of concentric grooves are formed in the end part of the welding head body; the welding needle is fixed on the bonding tool body, and sets up with the recess is concentric, and the main aspects of welding needle are provided with first screw thread portion, and the tip of welding needle is provided with second screw thread portion, and first screw thread portion revolves to opposite with second screw thread portion, and the diameter of welding needle main aspects is greater than the diameter of welding needle tip, and the diameter of welding needle main aspects is: phi 5.8-7.8, the diameter of the small end of the welding pin is as follows: phi is 3.5 to 4.5; the height of the supporting tool and the radial runout of the circumference after being unfolded are both less than or equal to 0.1mm, and the gap at the composite position of the rim and the spoke is less than or equal to 0.3mm.