CN101716632A - Reforming method and mold of automobile rear axle driven gear forging piece - Google Patents

Abstract

The invention relates to a reforming method and a mold of an automobile rear axle driven gear forging piece; the method comprises the following steps: prepare a semi-finished product-a chambering piece of the driven gear forging piece, place the manufactured chambering piece into a reforming mold cavity and reform the driven gear forging piece; the mold comprises a male mold, a female mold and a stripper plate, wherein the female mold is composed of a floating mold and a closed cavity formed by a pair of rollers; the invention can effectively reform the chambering piece of the driven gear, eliminate the disadvantages of concave pit, oval shape and distortion of the surface of the chambering piece, adopt equipment with low load and simple structure can effectively reform the driven gear forging piece of the automobile rear axle and saves more than 10 percent of raw material; for instance, the driven gear forging piece with 430mm of outer diameter is reformed, the needed load is 6300kN and the blanking weight is 36 kilograms.

Description

Shaping method and mold for forging of driven gear of automobile rear axle

technical field

The invention relates to a method and a mold capable of shaping the reamed automobile rear axle driven gear blank, which can eliminate surface pits of the blank reamed by a reaming machine, and can effectively improve the blank roundness and flatness.

Background technique

The driven gear of the rear axle of the automobile is one of the key parts for the power transmission of the main gearbox of the rear axle of the automobile, as shown in Figure 1, and its forging is a ring forging. At present, the main production process is: upsetting → punching → piercing → flattening → reaming. The defects of the forging after reaming include: (1) pits on the end surface; (2) large ovality ( ≥1mm); (3) distortion. Therefore, the unilateral machining allowance of the forging design is 2.5-4mm, and the material consumption is relatively large.

In order to improve the utilization rate of materials, the methods adopted at present are: (1) use a press to shape it after reaming; (2) use a rotary rolling machine to shape it. The first method of shaping requires a large tonnage of equipment (presses of more than 2,000 tons), and the cost of the equipment is high, and it cannot effectively eliminate the ellipticity of the forging; the second method of shaping is the local cumulative deformation of the metal, and the required equipment tonnage is the first. 1/5 to 1/15 of that, which can effectively eliminate the defects of the blank after reaming. However, the rolling force is an eccentric load, which requires the equipment to withstand the eccentric load. It has high requirements for the equipment structure and high equipment cost. Moreover, Oscillating rolling shaping is thermal shaping (the temperature of the blank is above 900°C), the life of the swinging ball chain is relatively low, and the maintenance cost of the equipment is relatively high.

Contents of the invention

The technical problem to be solved by the present invention is: in order to solve the problems existing in the prior art, provide a kind of shaping method and mold of the automobile rear axle driven gear forging after symmetrical twin-roll rolling shaping and reaming, this method can effectively eliminate Due to the defects in the blank, the required equipment load is small; the mold has a simple structure and is easy to manufacture.

The present invention solves its technical problem and adopts the following technical solutions:

The automobile rear axle driven gear forging shaping method provided by the invention adopts the method comprising the following steps:

(1) Prepare the semi-finished product of the driven gear forging:

After upsetting, punching, punching, flattening and reaming processes, the expansion part is manufactured. The reaming part is a semi-finished product of the driven gear forging. The external taper of the reaming part remains unchanged, and the internal taper is 0. , the outer diameter is reduced by 4mm on the basis of the driven gear forging, the inner diameter is increased by 1mm on the basis of the driven gear forging, and the height dimension is calculated under the principle of keeping the volume equal;

(2) Put the manufactured reaming part into the cavity of the plastic mold. The size and shape of the outer circle of the punch in the mold are the same as the size and shape of the inner circle of the driven gear forging. Use the punch of the mold to position it. The inner hole of the reamer fits on the outer circle of the punch;

(3) Shaping of driven gear forgings: the concave die of the shaping die is composed of a floating die and a closed cavity formed by a pair of rolls. Driven by the main shaft, the pair of rolls rotate around the axis of the main shaft 1, which is revolution ;Under the action of the friction between the shaped part and the floating die, the roll rotates around the axis of the roll, both revolving and rotating to roll and deform the metal, and at the same time form a closed cavity with the floating die, and move up with the slider , the reaming part becomes thinner and fills the inner ring of the floating die and the outer ring of the punch to complete the shaping of the reaming part.

Through the above steps, the shaping of the driven gear forging of the rear axle of the automobile is completed.

The shaping mold that realizes above-mentioned method that the present invention provides, comprises die, convex die and unloading hoop.

The structure of the die is as follows: it consists of a floating die and a pair of rolls symmetrically distributed left and right.

The two rolls take the axis of the main shaft as the axis of symmetry, the axis of the rolls and the axis of the main shaft are on the same plane, and the angle between the axis lines of the two rolls is 90°; the cone angle of each roll is 90°, and the top is processed with a hexagonal platform of the punch. This hexagonal platform is used not only to ensure the concentricity of the roll axis and the roll axis, but also to prevent the relative rotation between the roll axis and the roll.

A butterfly spring is installed at the bottom of the floating mold, and the elastic force ranges from 0 to 300kN. This elastic force ensures that the floating mold and the roll form a closed cavity during the shaping process. The geometric shape and size of the cone surface and the outer cylinder are consistent, and the hexagonal platform of the floating mold is processed on the floating mold. The hexagonal platform not only ensures the centering of the floating mold, but also prevents the floating mold from rotating with the roll.

The structure of the punch is: the shape and size of the upper part are consistent with the shape and size of the inner circle of the driven wheel forging, the middle part is a cylindrical shape, and its diameter is the maximum diameter of the inner hole of the driven wheel forging, and the lower part is the hexagonal platform of the punch. This hexagonal table ensures that the punch is centered and also prevents the punch from rotating.

A release ring is installed between the punch and the floating die.

The structure of the discharge ring: it is a ring, the inner ring is circular, its size matches the diameter of the cylinder of the punch, and it can slide along the cylinder; the outer ring is composed of three parts, the shape and size of the upper end surface are the same as that of the driven wheel forging The shape and size of the lower end face are consistent, the middle part is a cylinder, the diameter is the forging of the driven wheel, and matches the diameter of the inner ring of the floating die to ensure that it can slide up and down in the inner ring of the floating die, and the lower part is a hexagonal platform of the floating die. The height of this hexagonal platform is 5 to 10 mm higher than the height of the top material.

Compared with the prior art, the present invention has the following main advantages:

One. This method utilizes the local axial rolling cumulative deformation method and the mold to carry out axial rolling shaping on the reaming part, so the defects of the reaming part can be effectively eliminated.

Its two. Owing to can effectively eliminate the defect that the reaming part exists, therefore, can effectively carry out shaping to the automobile rear axle driven gear forging.

Third. In the process of eliminating the defects in forgings, because of the local cumulative deformation, the required equipment load is small. And because the rolling force is symmetrically distributed, there is no eccentric load, so the required equipment has a simple structure, and there is no spherical chain, so the service life is long.

4. The convex mold of the provided mold is fixed on the slider, and the concave mold is composed of a pair of symmetrically rotating conical rollers and elastic floating molds. The axial rolling and cumulative deformation of the shaped part form a closed cavity with the floating die at the same time. Because of the rolling cumulative deformation, the required deformation force is small and the die life is long. During the rolling process, the floating die and the tapered roll A closed cavity is formed, therefore, no flash occurs, no trimming process is required, and raw materials are saved.

In a word, the present invention can effectively eliminate the defects existing in the forgings, can effectively shape the forgings of the driven gear of the rear axle of the automobile by adopting simple-structured equipment, and can effectively save raw materials, saving more than 10% of raw materials, for example, shaping the outer diameter About 430mm driven gear forging, the machining allowance of the original forging design is 3 to 4 mm on one side, and the blanking weight is 41 kg, while the machining allowance of the forging after shaping by the present invention is 1 to 2 mm, and the blanking weight is 36 kg, while utilizing the required load of the present invention is 6300kN.

Description of drawings

Fig. 1 is a longitudinal sectional view of the general drawing of the mold of the present invention.

Fig. 2 is a longitudinal sectional view of a forging of the present invention

Fig. 3 is a longitudinal sectional view of the hole reamer of the present invention.

Fig. 4 is a longitudinal sectional view of the mold of the present invention at the beginning of shaping.

Fig. 5 is a longitudinal sectional view of the finished mold of the present invention.

Fig. 6 is a structural view of the roll of the present invention.

FIG. 7 is a top view of FIG. 6 .

Fig. 8 is a B-B sectional view of Fig. 9 .

Fig. 9 is a structural diagram of the floating mold of the present invention.

Fig. 10 is a structural diagram of the unloading hoop of the present invention.

FIG. 11 is a top view of FIG. 10 .

Fig. 12 is a view along the direction A of Fig. 10 .

Fig. 13 is a structure diagram of the punch of the present invention.

Fig. 14 is a view along the direction A of Fig. 13 .

Fig. 15 is a structural diagram of the fixing plate of the present invention.

Fig. 16 is a view from the direction A of Fig. 15 .

In the figure: 1. Main shaft axis line; 2. Main shaft; 3. Roller shaft; 4. Roller axis line; 5. Pull rod; 6. Bearing seat; 7. Reinforcing plate; 8. Roller; circle; 10. the first hexagon socket head cap screw; 11. the second hexagon socket cap screw; 12. the first fastening bolt; 13. punch; 14. floating die; 17. Second compression ring; 18. Fixed plate; 19. Butterfly spring; 20. Die base; 21. Ejector rod; 22. Ejector plate; 23. Key; 24. Fastening thread kit; ;26. Ejection oil cylinder; 27. Main oil cylinder; 28. Reaming piece; 29. Driven wheel forging; 30. Roller hexagonal platform; ; 34. Hexagonal guide groove; 35. Small hexagonal pit.

Detailed ways

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples.

1. The shaping method of the driven gear forging of the rear axle of the automobile

The shaping method employs a method comprising the following steps:

(1) Prepare the semi-finished product of the driven gear forging:

The reaming parts are manufactured through the process of upsetting → punching → punching and continuous skin → flattening → reaming. The shape of the reaming parts is similar to that of the driven gear forging (as shown in Figure 3). The reaming parts ( As shown in Figure 2) the outer taper (A1, A2) is basically unchanged, the inner taper A3 becomes 0, the outer diameter is reduced by 4mm on the basis of the driven gear forging, and the inner diameter is increased on the basis of the driven gear forging 1mm, under the principle of keeping the volume equal, calculate the height dimension change h, and increase the height of the reaming piece according to the method shown in Figure 3.

(2) the manufactured reamer (as shown in Figure 3) is put into the mold (Fig. 1) of the present invention, the size and shape of the outer circle of the punch 13 in the mold are identical with the inner circle size and shape of the driven wheel forging , using the punch 13 of the mold for positioning, that is, the inner hole of the reaming part is set on the outer circle of the punch 13, as shown in Figure 4.

(3) As shown in Figure 4, the concave die is composed of a closed cavity formed by a floating die 14 and a pair of rolls 8, and a pair of rolls 8 rotate around the axis 1 of the main shaft under the drive of the main shaft 2, that is, revolution ( Fig. 1), under the effect of the friction force of the reaming part and the floating die, the roll 8 rotates around the axis of the roll again, and when the metal is rolled and deformed by revolution and rotation, it forms a closed cavity with the floating die 14. As the slider moves upward, the reaming part becomes thinner and fills the inner hole of the floating die and the outer ring of the punch, completing the reshaping of the reaming part, as shown in Figure 5.

After the above steps, the shaping of the driven gear forging of the rear axle of the automobile is completed.

2. Reshaping die for forgings of driven gear of automobile rear axle

The structure of the plastic mold is shown in Figure 1: it includes a die, a punch and a material ring.

The structure of the die: the die is composed of a floating die 14 and a pair of rolls 8 .

As shown in Figures 6 and 7: the cone angle of the roll 8 is 90°, and the top of the roll 8 is processed with a hexagonal table 30 for the roll. Prevent relative rotation between the roll shaft 3 and the roll 8 . As shown in Figure 4: two rolls 8 take the main shaft axis 1 as the axis of symmetry, the roll axis 4 and the main shaft axis 1 are in the same plane, and the angle between the two roll axes 4 is 90°.

Two rollers 8 (left and right symmetry) are fixed on the roller shaft 3 by the first compression ring 9, pull rod 5, first hexagon socket head cap screw 10, second hexagon socket cap screw 11, reinforcement plate 7. A hexagonal boss with a height of h1 is processed on the upper end of the roll 8, which is called a hexagonal platform 30 of the roll. The side-to-side distance of the hexagonal platform is L1. There is no relative rotation and relative sliding between the roll shaft 3 ; the floating mold 14 is mounted on the fixed plate 18 by using the second fastening bolt 16 and the second compression ring 17 .

The bottom of the floating mold 14 is made with a hexagon, which is called the hexagonal platform 31 of the floating mold. The height of the hexagonal platform is h2, and the size of the side and the side is L2. Float up and down in the pit, prevent the eccentricity and rotation of the floating mold 14 simultaneously, and the dimensions D1, H3 of the floating mold cavity are equal to the size of the driven wheel forging 29. The upper half of the outer ring 15 (as shown in Figures 10, 11, and 12) is circular, and its diameter is equal to the maximum outer diameter of the driven wheel forging. The lower part is a hexagonal platform, and the height of the hexagonal platform is h3 higher than the height of the top material. Higher than 5 to 10mm, the distance between the sides of the hexagonal platform is L3, and this hexagonal platform slides up and down in the hexagonal guide groove 34 of the fixed plate 18, and prevents it from rotating.

The punch 13 (as shown in Figures 13 and 14) has a hexagonal boss with a lower height of h4 (the distance from side to side is L4) and is installed in a regular hexagonal pit with a depth of h5 on the fixed plate, and h4 is 3 to 3 larger than h5. 5mm, use the first fastening bolt 12 to fix the punch 13 on the fixed plate 18, the diameters of the punch cavity d1, d2, d4 are equal to the size of the driven wheel forging; use the second fastening bolt 16, the second pressing The ring 17 fixes the fixed plate 18 on the mold base 20 .

6 spring seats are made on the fixed plate 18 (Fig. 15, Fig. 16), and small hexagonal pits 35 (the depth of the hexagon is h5, and the side-to-side distance is L4) are made to ensure that the punch 13 is centered and prevents The punch rotates, and a hexagonal guide groove 34 is also made, the height of which is h6 (2 to 3 mm smaller than h3), and the side-to-side distance L3 is determined according to the maximum outer diameter of the driven gear forging, which is generally smaller than the maximum outer diameter of the driven gear forging 10～20mm, the effect of hexagonal guide groove 34 is to guarantee that floating mold slides therein and prevents it from rotating. Also be made on the fixed plate 18 and be deep to be the big hexagonal pit 33 of h7, the side-to-side dimension of big hexagonal pit is L2, and its effect is to guarantee that floating mold slides up and down wherein, and prevents die from rotating; The sleeve 24 fixes the mold base 20 on the slide block 25 of the tapered roller rolling machine, and 4 keys 23 of symmetrical distribution are installed between the mold base and the slide block 25, and the keys are used to prevent the mold base from rotating relative to the slide block.

The structure of the floating die 14 is shown in Figure 8 and Figure 9: the floating die 14 is processed with a floating die hexagonal platform 31, which not only ensures the centering of the floating die, but also prevents the floating die from rotating with the rolls. A butterfly spring 19 (as shown in Figure 1) is installed at the bottom of the floating mold 14, and the elastic force ranges from 0 to 300kN. This elastic force ensures that the floating mold and the rolls form a closed cavity during the shaping process. The shape and size of the cavity It is consistent with the shape and size of the upper plane (between D2 and d4), the back cone surface (cone angle A1), and the outer cylinder (diameter D1, height H3) of the driven wheel forging (as shown in Figure 2).

The structure of the punch 13 is shown in Figure 13 and Figure 14: the shape and size of the upper part are consistent with the shape and size of the inner circle of the driven wheel forging, the middle part is a cylinder, and its diameter is the maximum diameter d1 of the inner hole of the forging, and the lower part is Part is the hexagonal platform 32 of the punch, which can ensure the centering of the punch and prevent the rotation of the punch.

The structure of the feeding ring 15 is shown in Figure 10 to Figure 12: the structure of the feeding ring is a ring, and the inner ring is circular, and its size matches the diameter of the punch cylinder to ensure that it can slide along the cylinder; The ring is composed of three parts. The shape and size of the upper end surface are consistent with the shape and size of the lower end surface of the driven wheel forging. The inner ring slides up and down, and the lower part is a hexagonal platform, and the height of this step is 5 to 10mm higher than the height of the ejector.

Other undescribed components and related components will be described below in conjunction with the accompanying drawings.

As shown in Figure 1: two rolls 8 are supported by bearing housings 6, and driven by the main shaft 2 of the tapered roller rolling machine to rotate around the main shaft axis 1, as shown in Figure 3 is the reaming part 28 to be shaped , put the reaming part 28 to be shaped into the mold shown in Figure 1, under the action of the main oil cylinder 27 in the ejection cylinder 26 of the tapered roller rolling machine, the slider 25 moves upwards, driving the mold base 20 , fixed plate 18, punch 13, material ring 15 and the reaming part 28 to be shaped move upward, when the reaming part 28 upper surface to be shaped touches the roll 8 (position shown in Figure 4), the frictional force Under the action of rolling, the roll 8 and the roll shaft 3 start to rotate around the roll axis 4, and the rolling deformation of the upper surface and the side cone surface of the reaming part 28 is realized under the combined action of the roll rotating around the main shaft and around the self-axis , in the process of rolling deformation, under the action of the elastic force of the disc spring 19, the upper surface of the floating die 14 is always in contact with the roll 8, forming a closed cavity, that is, a concave cavity, and forcing the reaming part 28 to metal during the deformation process. Flow in a closed cavity. When the slider 25 of the main oil cylinder drives the punch 13 and the discharge ring 15 to continue to move upward, the roll 8 and the floating die 14 do not move in the vertical direction. Under the action of the feeding ring 15, the metal is extruded and deformed, and the cavity formed by the concave die formed by the floating die 14 and rolls and the relatively moving punch and the feeding ring is formed. When the shaped reaming member 28 reaches the required uniform thickness, that is, when the state shown in Figure 5, the slider 25 goes down quickly, and when it reaches the lower limit position, the ejector plate 22 moves upward, passing through three evenly distributed The ejector rod 21 pushes up the feeding ring 15, and the feeding ring pushes out the driven wheel forging 29, and the ejection height is greater than H1 in Fig. 1 .

Claims (10)

1. the shaping mould of an automobile rear axle driven gear forging piece comprises die and punch, it is characterized in that:

The structure of die is: forms by the roll (8) that float mould (14) and a pair of left-right symmetry distribute,

Two rolls are symmetry axis with spindle axis line (1), roll axial line (4) and spindle axis line (2) 1 plane that coexists, and the angle between two roll axial lines is 90 °; The cone-apex angle of each roll is 90 °, and the top is processed with punch six side's platforms (32), and both as guaranteeing roll axial line and the concentric usefulness of roll mandrel axial line (4), conduct prevented to produce relative rotation between roll mandrel (3) and the roll (8) this six sides platform again,

Unsteady mould (14) bottom is equipped with butterfly spring (18), the elastic force excursion is 0 to 300kN, this elastic force guarantees unsteady mould and roll formation near closed hollow ring in the process of shaping, the geometry and the consistent size of last plane, back cone and the outside cylinder of this cavity shape and size and driven pulley forging, on the mould that floats, be processed with the mould six side's platforms (31) that float, this six sides platform had both guaranteed to float mould to the center, and the mould that prevents from again to float is with roll rotation;

The structure of punch (13) is: toroidal and consistent size in its first half shape and size and the driven pulley forging, mid portion is one cylindrical, and its diameter is a forging endoporus maximum diameter d 1, and the bottom is divided into punch six side's platforms (32), this six sides platform guarantees punch to the center, prevents that also punch from rotating;

Between punch (13) and unsteady mould (14), discharging circle (15) is installed;

Discharging circle (15) structure: be an annular element, inner ring is circular, and its size and punch cylinder diameter size match, and assurance can be slided along cylinder; The outer ring is made up of three parts, upper surface shape and size and driven pulley forging lower surface shape and consistent size, mid portion is one cylindrical, diameter is the driven pulley forging, and match with unsteady mould inner ring diameter, assurance can slide up and down in unsteady mould inner ring, and the bottom is a unsteady mould hexagon platform (31), and this six sides platform height ratio liftout height exceeds 5 to 10mm.

2. the shaping mould of automobile rear axle driven gear forging piece according to claim 1, it is characterized in that: two rolls (8) are fixed on the roll mandrel (3) by first compacting ring (9), pull bar (5), first soket head cap screw (10), second soket head cap screw (11), stiffener (7), and roll mandrel is by bearing block (6) movable supporting.

3. the shaping mould of automobile rear axle driven gear forging piece according to claim 2, it is characterized in that: on stiffener (7), be provided with six side's pits, be processed with roll six sides protruding (30) in the upper end of roll (8), this six sides boss cooperates with positive six side's pits of stiffener (7) and links to each other.

4. the shaping mould of automobile rear axle driven gear forging piece according to claim 1, it is characterized in that: die holder (20) is fixed on the slide block (25) with binding thread external member (24), the key (23) of four symmetrical distributions is installed between die holder and slide block (25), and this key is used for preventing that die holder from rotating relative to slide block.

5. the shaping mould of automobile rear axle driven gear forging piece according to claim 4, it is characterized in that: fixed head (18) and the unsteady mould (14) that is attached thereto are fitted on the die holder (20) with second fastening bolt (16) and second compacting ring (17).

6. the shaping mould of automobile rear axle driven gear forging piece according to claim 5 is characterized in that: be manufactured with the butterfly spring abutment that is used to install butterfly spring (19) on fixed head (18).

7. the shaping mould of automobile rear axle driven gear forging piece according to claim 5, it is characterized in that: on fixed head (18), be manufactured with six side's gathering sills (34), it is tall and big in liftout height 5～10mm, and its edge-to-edge's distance is less than 10～20mm of driven gear forging piece (29) maximum outside diameter of shaping.

8. the shaping mould of automobile rear axle driven gear forging piece according to claim 5, it is characterized in that: in fixed head (16), be manufactured with big six side's pits (33) and little six side's pits (35), the mould six side's platforms (31) that float are made in unsteady mould (14) bottom, this six sides platform is packed in big six side's pits (33), punch six side's platforms (32) of punch (13) bottom are packed in little six side's pits (35) of fixed head (16), the mould that floats slides up and down in the guiding of big six side's pits (33) of fixed head (16), and the mould (14) that prevents to float rotates.

9. the shaping mould of automobile rear axle driven gear forging piece according to claim 1, it is characterized in that: roll (8) rolling surface is the planar end surface and the back cone of driven gear forging piece.

10. the shaping methods of an automobile rear axle driven gear forging piece is characterized in that adopting that the described shaping mould of arbitrary claim carries out shaping to automobile rear axle driven gear forging piece in the claim 1 to 9, and its step comprises:

(1) semi-finished product of preparation driven gear forging piece:

Expand part (28) through jumping-up, punching, punching the wad, pressing and the manufacturing of chambering process process, made reaming part is the semi-finished product of driven gear forging piece, the external taper of this reaming part is constant, the inner cone tapering is 0, outside diameter reduces 4mm on the basis of driven gear forging piece, interior circular diameter increases 1mm on the basis of driven gear forging piece, under the principle that keeps volume to equate, calculate height dimension;

(2) the reaming part of manufacturing is put into the shaping mould die cavity, punch in this mould (13) excircle dimension is identical with the interior round size and shape of shape and driven gear forging piece, utilize punch (13) location of mould, the inner hole sleeve that is about to the reaming part is on the cylindrical of punch (13);

(3) shaping of driven gear forging piece: the die of shaping mould is made up of unsteady mould (14) and the formed near closed hollow ring of a pair roller (8), a pair roller (8) rotates around spindle axis line (1) under the drive of main shaft (2), this is revolution, under by the effect of the friction of shaping piece and unsteady mould, roll (8) is again around the rotation of roll axial line, not only revolved round the sun but rotation when metal is rolled distortion and unsteady mould (14) form near closed hollow ring, along with slide block moves up, the attenuation of reaming part is full of float mould inner ring and punch outer ring, finishes the shaping to the reaming part;

Through above-mentioned steps, finish the one-tenth shaping of automobile rear axle driven gear forging piece.

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