JPH09122815A - Production of constant velocity coupling outer ring and its inner die device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To have good productivity in comparison with cutting and to obtain high precision quality having good filling property in comparison with conventional forging method. SOLUTION: In a method to forge a crossing groove 3 on the inner face of a cup shaped preform W, an inner die 4 having a crossing groove 4a on the outer circumference is inserted into the cup shaped preform W. At this state, by repeatedly striking the outer diameter face of preform W with a outer die 6 of a rotating striking device 5, the crossing groove 3 is formed on the inner diameter face of preform W. As for the inner die 4, the crossing groove die 4a is arranged to plural segments 18 arrayed in the circumferential direction, diameter reduction is made possible by moving the segment 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing method for manufacturing an outer ring, which is a constituent part of a constant velocity universal joint for power transmission used in an automobile or the like, by forging, and an inner die apparatus thereof.

[0002]

2. Description of the Related Art In a constant velocity universal joint, an outer ring 50 having a cup portion 51 and a shaft portion 52 is generally used as shown in FIG. On the inner diameter surface of the cup portion 51, an intersecting groove 53 that serves as a track groove of the ball is provided so as to be inclined with respect to the axial direction. Conventionally, to manufacture the outer ring 50 having such a shape, the inner diameter portion of the cup portion 51 is cut by cutting the cross groove 53 and the inner diameter surface 5 based on the forged rough formed product Wa as shown in FIG.
1a is processed, quenched, and then finished by grinding. In addition to this, as an application of plastic working, a method of inserting an inner die (not shown) into a forged rough-formed product Wa as shown in FIG. 5 and squeezing the outer diameter from the axial direction has been attempted. .
As another application of plastic working, the forged rough-formed product W
There is also proposed a method in which an inner mold is put in a and the outer periphery is pressed by a plurality of outer molds to form a cross groove that follows the inner mold (Japanese Patent Publication No. 5-62007).

[0003]

However, in the above-mentioned cutting method, a great number of man-hours are required for forming the cross groove and the inner diameter, which causes an increase in the cost of the product. In the case of the above-mentioned ironing method, the filling property of the material Wa into the inner mold is poor, and it is difficult to form a good quality shape. Further, in the method of pressurizing the outer circumference with a plurality of outer dies, since each outer die is pressurized at one time, a high output drive source is required, There is a problem in that the outer circumference of the material Wa is caught in the circumferential gap between the outer dies and burrs (fine projections) are generated.

An object of the present invention is that the productivity is higher than that of cutting, the filling quality is higher and the quality of precision is better than that of the conventional forging method, and the driving source for striking is a small output. (EN) Provided are a method for manufacturing an outer ring for a constant velocity universal joint, and an inner mold apparatus thereof.

[0005]

The manufacturing method of the present invention comprises:
A method for manufacturing a constant velocity universal joint outer ring, comprising forging a cross groove on an inner diameter surface of a cup-shaped material, wherein an inner die having a cross groove shape on the outer periphery is inserted into the cup-shaped material. In this state, by repeatedly striking the outer diameter surface of the material with a rotary striking device, a cross groove is formed on the inner diameter surface of the material so as to follow the cross groove type. By using the rotary hammering device in this way, it is possible to repeatedly hit the material from the outer periphery of the material in the radial direction at high speed repeatedly, which allows for high-precision quality with good filling even in cold forging. Is obtained. Further, since the rotary striking device is used, the striking is carried out successively little by little, so that the driving source for pressurizing or striking can be of a small output. As the inner mold, it is preferable to use one in which a plurality of segments arranged in the circumferential direction are provided with intersecting groove molds and the diameter of which can be reduced by moving the segments. When the inner die having this structure is used, it is possible to reduce the diameter of the inner die and to extract the inner die in the axial direction after forming the cross groove. By using the inner mold capable of reducing the diameter in this way, the inner mold can be smoothly extracted without generating an excessive force between the cross grooves.

The inner die apparatus for manufacturing a constant velocity universal joint outer ring of the present invention is an inner die used together with a rotary impacting apparatus for impacting the outer diameter surface of a material when forging a cross groove in the inner diameter surface of a cup-shaped material. A device comprising an inner mold and a diameter reducing ring. In the inner mold, a plurality of segments are provided on the outer periphery of a shaft-shaped punch base, and a knockout is movably inserted into the shaft center of the punch base. Each segment has an inner diameter surface forming surface that forms a part of the inner diameter surface of the material and a cross groove type, and a positioning slope surface and a diameter reducing slope surface are formed on the inner diameter side and the outer diameter side, respectively. is there. The punch base is formed with an inner diameter surface forming surface for forming the remaining part of the material inner diameter surface and a plurality of fitting grooves into which each segment fits, and the bottom surface of the fitting groove is in surface contact with the positioning slope surface. It is used as a segment positioning surface. The diameter-reducing ring has a guide slope surface that is provided so as to be movable in the axial direction and that presses the diameter-reducing slope surface of the segment. According to the inner die device of this configuration, after molding, the punch base is moved in the pull-out direction to make the segment radially inward, and the segment can be pushed in the axial direction by the guide slope surface of the diameter-reducing ring. The segment is moved inward to shrink the inner mold. As a result, the cross groove mold is disengaged from the cross groove of the formed material, and the inner mold can be pulled out in the axial direction.

[0007]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described with reference to FIGS. In this method for manufacturing a constant velocity universal joint outer ring, a cup-shaped material W having one end closed shown in FIG. 1 (A) is forged, and a molded product (W) is obtained as shown in FIGS. 1 (C) and 1 (D). This is a method of forging the intersecting groove 3 and the inner diameter surface 1a as shown, and is performed as follows. The material W is roughly formed by forging in the previous step, and has a cup portion 1 and a shaft portion 2 protruding from the back surface thereof. First, an outline method will be described. As shown in FIG. 1 (B), the cup-shaped material W has an inner mold 4
Insert As the inner die 4, one having a cross groove die 4a on the outer circumference is used, and the outer diameter surface of the material W is repeatedly hit by the outer die 6 of the rotary hitting device 5 shown in FIG. The cross groove 3 that follows the cross groove mold 4a is formed on the inner diameter surface of W. Simultaneously with this molding, the inner diameter surface 1a of the cup portion 1 of the material W is also molded. By using the rotary striking device 5 as described above, the material W can be repeatedly striked from the outer periphery in the radial direction at high speed many times. It is possible to obtain highly accurate quality with good filling property.

The rotary striking device 5 is a so-called rotary aging type rotary forging machine, and a commercially available one can be used. The rotary striking device 5 forms a cylindrical pressing surface 6a with a plurality of radially arranged outer dies 6, and in this example, four outer dies 6 are used. These outer dies 6 have guide grooves 8 provided on the spindle 8.
A wedge-shaped shim 9 and a cam 10 are fitted in a so as to be able to move forward and backward in the radial direction. Spindle 8 and housing 11
Each time the roller 12 rolling between the outer rings 11a passes through the guide groove 8a, the outer die 6 is pressed inward in the radial direction via the cam 10 and the shim 9. Roller 12
Is a striking member for the outer die 6, and rolls in a cylindrical gap between the spindle 8 and the outer ring 11a by relatively rotating the spindle 8 and the outer ring 11a. As shown in FIG. 2, the cam 10 and the shim 9 have contact surfaces with each other as inclined surfaces, and by moving the cam 10 in the axial direction, a stroke in the radial direction of the outer die 6 is given. Each roller 12 is a roller guide 1 provided in the housing 11.
3 is positioned in the axial direction. When forming the material W, the cam 1
By gradually advancing 0, the outer die 6 is moved to the inner diameter side while rotating, the outer diameter surface of the material W is narrowed and the inner diameter surface is pressed against the inner die 4, and the cross groove 3 is formed. Alternatively, the outer die 6 may also be formed with a tapered pressure surface, and instead of moving the cam 10 in the axial direction, the cam 10 may be moved in the axial direction by the material to form the outer die 6
It is also possible to squeeze with the tapered pressure surface while rotating.

FIG. 3 shows the internal device 15 and its operation. The same figure (A) shows the state at the time of completion of molding, and the same figure (B)
Shows the inner mold diameter reduction state immediately after the completion of molding. Internal device 15
Is mainly composed of the inner mold 4 and the diameter-reducing ring 16, and a width retainer 28 is provided facing the inner mold 4. The width presser 28
It is a member that supports the back surface of the cup portion 1 of the material W, and has a shaft portion fitting hole 28a into which the shaft portion 2 is fitted. Inner mold 4
Is provided with a plurality of (six in this example) segments 18 on the outer periphery of the axial punch base 17, and the punch base 1
It is assumed that an umbrella-shaped knockout 19 is inserted in the axial center portion of 7 so as to be able to move back and forth. Each segment 18 has an inner diameter surface forming surface 18a for forming a part of the inner diameter surface of the material and an intersecting groove die 4a on the outer diameter side of the front portion.
8b is formed over the entire length on the inner diameter side, and a diameter reducing gradient surface 18c is formed on the rear portion on the outer diameter side. The punch base 17 is formed with an inner diameter surface forming surface 17a for forming the remaining portion of the material inner diameter surface and a plurality of fitting grooves 17b into which the respective segments are fitted, and the bottom surface of the fitting groove 17b is the positioning slope surface. The segment positioning surface 17ba is in surface contact with 18b. The deep side end of the fitting groove 17b is opened to the front end surface of the punch base 17, and the shallow side end is the segment 18.
Is used as the positioning engagement surface 17bb. The diameter-reducing ring 16 has a guide slope 16a that is provided in the ring-shaped stripper 29 so as to be movable in the axial direction and presses the diameter-reducing slope 18c of the segment 18.

The stripper 29 is a member that abuts the front end surface of the cup portion 1 of the material W, and is integrally connected to the cylinder case 21 of the cylinder device 20. The cylinder device 20 is a fluid pressure cylinder such as a hydraulic type that moves a piston rod 22 connected to the punch base 17 forward and backward, and a piston 22a on the outer periphery of the piston rod 22 is fitted in the cylinder chamber 21a. The piston rod 22 and the punch base 17 are hollow shafts, and a spring member 23 disposed inside of the piston rod 22 urges the knockout 19 to project. Rings 16 of reduced diameter are provided at a plurality of positions in the circumferential direction of the cylinder case 21.
A cylinder device 24 serving as a driving means is formed, and its piston rod 25 is connected to the diameter reducing ring 16. The diameter-reducing ring 16 is biased in the backward direction by a return spring 26.

The inner type device 15 is used as follows. The material W is sandwiched between the width presser 28 and the umbrella-shaped knockout 19 while guiding the shaft portion 2, and the inner mold 4 composed of the segment 18, the punch base 17, and the knockout 19 is formed as shown in FIG. 3A. Insert the inside of the cup portion 1 of W. Then, the outer diameter surface of the cup portion 1 of the material W is pressed by the rotary impacting device 5 through the rotating outer die 6, so that the material W has an inner diameter shape that follows the outer shapes of the segment 18 and the punch base 17. Is molded. After forming, the punch base 17 fastened to the piston rod 22 is extracted from the formed material W using the stripper 29, and the diameter reducing ring 16 is advanced by the cylinder device 26, whereby the diameter of the segment 18 is reduced. In this reduced diameter state, the formed material W is axially separated from the inner mold 4.

[0012]

EFFECTS OF THE INVENTION In the method for manufacturing a constant velocity universal joint outer ring of the present invention, an inner die having an intersecting groove type on the outer periphery is inserted into the cup-shaped material, and the outer diameter surface of the material is repeated by a rotary striking device. Since it is a method of forming an intersecting groove that follows the intersecting groove type on the inner diameter surface of the material by hitting with a hammer, the productivity is better than that of the cutting process, and the filling property is better than that of the conventional forging method. High quality is obtained. Also, since a rotary striking device is used, the driving source for striking can be small,
High quality with no burrs on the outer circumference can be obtained. If the inner mold is a reducible one in which a plurality of segments are provided with intersecting groove molds, and after molding, the inner mold is reduced in diameter to be pulled out in the axial direction from the material, the mold can be released easily. It can be done smoothly. The inner mold device of the present invention is used together with a rotary striking device, and includes an inner mold and a diameter reducing ring,
The inner die is provided with a plurality of segments on the outer periphery of the punch base, and the knockout is inserted into the shaft center so as to be able to move forward and backward. Since it has a groove shape and positions each segment in the radial and circumferential directions with the punch base, and the diameter of the segments is reduced with the diameter reducing ring after the punch base is retracted And the demolding can be done smoothly.

[Brief description of the drawings]

FIG. 1A is a cutaway side view of a material used in an embodiment of the present invention, FIG. 1B is a cross-sectional view of an essential part showing a manufacturing method thereof, and FIG. 1C is a cutaway side view of a molded material. (D) is the same front view, (E) is a fracture | rupture front view of a rotary impact device.

FIG. 2 is a cutaway side view and a cutaway perspective view of a rotary impact device.

3A and 3B are cross-sectional views of respective operating states of the inner mold device.

FIG. 4A is a cutaway side view of a conventional constant velocity universal joint outer ring, and FIG. 4B is a front view thereof.

FIG. 5 is a cutaway side view of a rough forged product of a raw material.

[Explanation of symbols]

1 ... Cup part, 2 ... Shaft part, 3 ... Cross groove, 4 ... Inner mold, 4a
... Cross groove type, 5 ... Rotary hitting device, 6 ... Outer mold, 8 ... Spindle, 9 ... Shim, 10 ... Cam, 11 ... Housing, 1
2 ... Roller, 15 ... Inner mold device, 16 ... Diameter reducing ring, 16
a ... guide slope surface, 17 ... punch base, 17a ... inner diameter surface forming surface, 17b ... fitting groove, 17ba ... positioning surface, 1
8 ... Segment, 18a ... Inner diameter surface forming surface, 18b ... Positioning slope surface, 18c ... Diameter reduction slope surface, 19 ... Knockout, 28 ... Width presser, W ... Material

Claims (3)

[Claims] 1. A method for manufacturing a constant velocity universal joint outer ring, comprising forging a cross groove on an inner diameter surface of a cup-shaped material, wherein an inner die having a cross groove shape on the outer periphery is inserted into the cup-shaped material, A method for manufacturing an outer ring for a constant velocity universal joint, which comprises repeatedly striking a radial surface with a rotary striking device to form a cross groove on the inner diameter surface of the material, the cross groove following the cross groove type. 2. The inner mold used is one in which a plurality of segments lined up in the circumferential direction are provided with the intersecting groove mold so that the diameter can be reduced, and after forming the intersecting groove, the inner mold is reduced in diameter. The method for manufacturing a constant velocity universal joint outer ring according to claim 1, wherein the outer ring is pulled out in the axial direction. 3. An inner die device used together with a rotary striking device for striking the outer diameter surface of a material when forging a cross groove on the inner diameter surface of a cup-shaped material, the inner die device and a reduced diameter ring, The inner mold is provided with a plurality of segments on the outer circumference of a shaft-shaped punch base, and a knockout is inserted into the shaft center of the punch base so that the knockout can advance and retreat. The inner diameter surface forming surface and the cross groove type, and the positioning slope surface and the diameter reducing slope surface are formed on the inner diameter side and the outer diameter side respectively, and the punch base molds the remaining portion of the material inner diameter surface. The inner diameter surface forming surface and a plurality of fitting grooves for fitting each segment are formed, and the bottom surface of the fitting groove is a segment positioning surface that makes surface contact with the positioning gradient surface. Freely movable An inner die device for manufacturing a constant velocity universal joint outer ring having a guide sloped surface for pushing the diameter-reducing sloped surface of the segment.