JPH11325094A - Constant velocity universal joint, manufacture of its cage and manufacturing device for the cage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a constant velocity universal joint to reduce a size in the direction of the thickness of a cage and facilitate manufacture of this cage and to provide a method and a device for manufacturing a cage. SOLUTION: By allowing movement in a radial direction of each ball 3, the size in the direction of thickness of the cage 4 is reduced. Therefore, grooves 1a and 2a can be formed more deeply by an amount equivalent to the reduced thickness of the cage, and a high rotation force is transferred. In this case, since the protrusion part 4b of the cage 4 is formed by partially and radially deviating the edge part of a hole 4a, by deforming the edge part of the hole by a press work, the protrusion 4b is easily formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant velocity universal joint used in, for example, a power transmission system of an automobile, a method of manufacturing a cage thereof, and an apparatus for manufacturing the cage.

[0002]

2. Description of the Related Art Conventionally, as a constant velocity universal joint of this kind,
An outer rotating body that rotates integrally with one rotating shaft, an inner rotating body that rotates integrally with the other rotating shaft, and a plurality of rotating bodies disposed between an inner peripheral surface of the outer rotating body and an outer peripheral surface of the inner rotating body. And a cage that holds each ball so that it can roll freely. In this constant velocity universal joint, a plurality of grooves extending in the axial direction are provided on the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, respectively. The rotating force of the rotating body is transmitted to each other via each ball. Also, the grooves of each rotating body and the corresponding peripheral surface are formed so as to form a curved shape in the axial section of each rotating body, whereby the swing center of each rotating shaft is held at a predetermined position. It is supposed to be.

[0003] The cage is provided with a plurality of holes for holding each ball, but when each ball rolls along with the swing of each rotation shaft, it slightly extends in the radial direction of the cage. To move, the cage needs to be thick enough to allow radial movement of each ball. However, when the dimension in the thickness direction of the cage is increased, the depth of the groove of each rotating body is reduced, so that there is a problem that the durability of the groove against the contact load of the ball is reduced. Therefore, as described in, for example, Japanese Patent No. 2678323, projections that partially protrude radially outward are provided at both ends in the axial direction of each hole of the cage, and the diameter of the ball is determined by the projections. There has been proposed an arrangement in which the cage is allowed to move in the direction to reduce the dimension of the cage in the thickness direction.

[0004]

However, in Japanese Patent No. 2678323, since the projection of each hole of the cage is integrally formed so as to be thicker than the cage body, material processing is performed. It is extremely difficult and disadvantageous in production, such as high production cost.

The present invention has been made in view of the above problems, and has as its object to reduce the size of a cage in the thickness direction and to easily manufacture the cage. It is an object of the present invention to provide a constant velocity universal joint, a cage manufacturing method thereof, and a cage manufacturing apparatus thereof.

[0006]

To achieve the above object, according to the present invention, an outer rotating body that rotates integrally with one rotating shaft and an inner rotating body that rotates integrally with the other rotating shaft are provided. Body, a plurality of balls respectively engaging with a plurality of grooves provided on an inner peripheral surface of the outer rotating body and a plurality of grooves provided on an outer peripheral surface of the inner rotating body, and an inner peripheral surface and an inner rotating body of the outer rotating body And a cage provided with a plurality of holes that respectively hold the respective balls so as to be able to roll freely, and the grooves of the respective rotating bodies are curved in the axial cross section of the respective rotating bodies. In the constant velocity universal joint in which the swing center of each rotating shaft is held at a predetermined position by forming as described above, the edge of the hole is radially inward or outward at both axial ends of each hole of the cage. Are provided with projections that are partially unevenly distributed. Thereby, the movement of the ball in the radial direction of the cage is permitted by each projection, so that the thickness dimension of the cage can be reduced.

According to a second aspect of the present invention, an outer rotating body that rotates integrally with one of the rotating shafts, an inner rotating body that rotates integrally with the other rotating shaft, and a plurality of rotating bodies provided on the inner peripheral surface of the outer rotating body. A plurality of balls that are respectively engaged with the grooves and a plurality of grooves provided on the outer peripheral surface of the inner rotating body, and are disposed between the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, and each ball rolls. A cage having a plurality of holes that can be freely held.Protrusions that project radially inward or outward are provided at both axial ends of each hole of the cage, and grooves of each rotating body are respectively formed on the shaft of each rotating body. In the method for manufacturing a constant velocity universal joint in which a swing center of each rotary shaft is held at a predetermined position by forming a curved shape in a cross section in the direction, the edge of each hole of the cage is formed. Radially inside the cage by partially deforming Others are so as to form a projection protruding outward. Thereby, the movement of the ball in the radial direction of the cage is allowed by the projection, so that the thickness of the cage can be reduced. In this case, the protrusion can be easily formed by partially deforming the edge of each hole of the cage radially inward or outward by pressing or the like.

According to a third aspect of the present invention, an outer rotating body that rotates integrally with one of the rotating shafts, an inner rotating body that rotates integrally with the other rotating shaft, and a plurality of rotating bodies provided on the inner peripheral surface of the outer rotating body. A plurality of balls that are respectively engaged with the grooves and a plurality of grooves provided on the outer peripheral surface of the inner rotating body, and are disposed between the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, and each ball rolls. It consists of a cage with a plurality of holes to hold freely, and the groove of each rotating body is formed so as to be curved in the axial cross section of each rotating body, so that the swing center of each rotating shaft is In the method for manufacturing a cage for a constant velocity universal joint that is held at a predetermined position, a notch of a predetermined shape is formed at an edge of each hole of the cage, and the periphery of the notch is partially bent to thereby reduce the diameter of the cage. Projection that projects inward or outward And so as to form a. Thereby, the movement of the ball in the radial direction of the cage is allowed by the projection, so that the thickness of the cage can be reduced. In this case, the protrusion can be easily formed by partially bending the periphery of the cut formed at the edge of each hole of the cage radially inward or outward.

According to a fourth aspect of the present invention, in the method for manufacturing a cage for a constant velocity universal joint according to the second or third aspect, a predetermined shape is respectively formed on an outer peripheral surface side and an inner peripheral surface side of the plastic tubular material to be the cage. A molding die is arranged, and a part of the cylindrical material in the circumferential direction is pressure-formed by moving the molding die on the inner peripheral surface toward the outside in the radial direction. In the circumferential direction, and the other portion in the circumferential direction of the tubular material is pressure-formed. Thereby, in addition to the operation of claim 2, the cylindrical material is pressed and formed by moving the forming die on the inner peripheral surface toward the outside in the radial direction. It can be easily formed into a curved shape along the peripheral surface of the rotating body.

According to a fifth aspect of the present invention, an outer rotating body that rotates integrally with one of the rotating shafts, an inner rotating body that rotates integrally with the other rotating shaft, and a plurality of rotating bodies provided on the inner peripheral surface of the outer rotating body. A plurality of balls that are respectively engaged with the grooves and a plurality of grooves provided on the outer peripheral surface of the inner rotating body, and are disposed between the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, and each ball rolls. It consists of a cage with a plurality of holes to hold freely, and the groove of each rotating body is formed so as to be curved in the axial cross section of each rotating body, so that the swing center of each rotating shaft is An apparatus for manufacturing a cage for a constant velocity universal joint which is configured to be held at a predetermined position, comprising: an outer molding die having a predetermined shape disposed on an outer peripheral surface side of a plastic cylindrical material to be the cage; and an inner peripheral surface of the cylindrical material. The cylindrical material is arranged on the side, circumferentially spaced from each other And a plurality of inner molds radial and circumferential directions movable respectively, predetermined shape. With this, by moving each inner mold toward the radially outer side, the cylindrical material is pressure-formed,
The peripheral surface of the cylindrical material can be easily formed into a curved shape along the peripheral surface of each rotating body.

According to a sixth aspect of the present invention, in the cage manufacturing apparatus for a constant velocity universal joint according to the fifth aspect, the inner peripheral surface of each of the inner forming dies is formed so as to be inclined in one axial direction. By inserting a tapered pressing member between the inner peripheral surfaces of the inner molds in the axial direction, each inner mold is moved radially outward. Thus, in addition to the operation of the fourth aspect, since each of the inner molds moves radially outward due to the insertion of the pressing member, each of the inner molds can be simultaneously moved with a uniform force.

[0012]

1 to 7 show one embodiment of the present invention. FIG. 1 is a side sectional view of a constant velocity universal joint, and FIGS. 2 (a) and 2 (b) show different circumferential directions. FIG. 3 is a side sectional view of the cage viewed from the position, FIG. 3 is a sectional view taken along line XX of FIG. 2, FIG. 4 is a side sectional view showing a state where the rotation axis is inclined, and FIG. FIG. 6 is an explanatory view of a contact ellipse acting on a groove,
FIG. 7 is a comparative explanatory view regarding the durability of the groove.

This constant velocity universal joint has one shaft S1
The outer rotating body 1 that rotates integrally with the other, and the other shaft S2
The inner rotating body 2 that rotates integrally with the inner rotating body, a plurality of balls 3 disposed between the inner peripheral surface of the outer rotating body 1 and the outer peripheral surface of the inner rotating body 2, and each of the balls 3 is rotatably held. And a cage 4.

The outer rotating body 1 is open at one end in the axial direction, and one shaft S1 is integrally provided at the other end. The inner surface of the outer rotating body 1 is formed in a spherical shape, and a plurality of grooves 1a extending in the axial direction are provided on the inner circumferential surface at equal intervals in the circumferential direction. In this case, each groove 1a and its corresponding peripheral surface are formed so as to be curved in the axial cross section of the outer rotating body 1, respectively.

The inner rotating body 2 is arranged inside the outer rotating body 1, and the other shaft S2 is axially penetrated and connected to the center in the radial direction. The outer surface of the inner rotating body 2 is formed in a spherical shape, and a plurality of grooves 2a extending in the axial direction are provided on the outer peripheral surface at equal intervals in the circumferential direction. In this case, each groove 2a and its corresponding peripheral surface are respectively
Are formed so as to be curved in the axial section.

Each of the balls 3 is arranged in the circumferential direction of each of the rotating bodies 1 and 2 and is rotatably engaged with the grooves 1a and 2a of each of the rotating bodies 1 and 2.

The cage 4 is formed in an annular shape, and its peripheral surface is curved along the inner peripheral surface of the outer rotor 1 and the outer peripheral surface of the inner rotor 2. The cage 4 is provided with a plurality of holes 4a for holding the respective balls 3 at equal intervals in the circumferential direction, and at both ends in the axial direction of each hole 4a, a projection 4b projecting radially inward is provided. In this case, each projection 4b is formed by partially displacing the edge of the hole 4a in the radial direction. That is, the cage 4 is formed to have a uniform thickness except for the projections 4b, and is interposed between the peripheral surfaces of the rotating bodies 1 and 2 in a contact state, and the projections 4b are formed in the grooves 2a of the inner rotating body 2. It is arranged to protrude into. Further, the cage 4 is provided with a hole 4a formed in an oval shape and a hole 4a formed in a substantially square shape as shown in FIGS. 2 (a) and 2 (b).
The shape of the oblong hole 4a is necessary when the cage 4 is assembled to each of the rotating bodies 1 and 2, and is not directly related to the gist of the present invention.

In the constant velocity universal joint constructed as described above, each ball 3 is engaged with the grooves 1a, 2a of each of the rotating bodies 1, 2 so that the rotational force of each shaft S1, S2 is reduced. To each other via As shown in FIG. 4, when the rotation axes of the shafts S1 and S2 form an arbitrary angle .theta., The balls 3 roll along the grooves 1a and 2a while being held by the cage 4. At this time, according to a well-known principle, as shown in FIG. 1, the center O1 of the curved surface of the inner peripheral surface of the outer rotating body 1 and the center O2 of the curved surface of the outer peripheral surface of the inner rotating body 1 are shifted from a plane passing through the center of each ball 3. By being formed so as to be deviated in the axial direction by the same distance L, as shown in FIG. 4, the contact point between each ball 3 and each groove 1a, 2a always divides the intersection angle .theta. It is located on the plane to be. As a result, the rotational force of each shaft S1, S2 is always transmitted at the same angular velocity. Also, the grooves 1a,
2a and the corresponding peripheral surface are respectively rotating bodies 1, 2
Is formed so as to be curved in the axial section thereof, so that the swing center O of each of the shafts S1 and S2 is maintained at a constant position even if the crossing angle of each rotating shaft changes.

In the above constant velocity universal joint, each shaft S 1,
When each ball 3 rolls along each groove 1a, 2a by the swing of S2, each ball 3 also moves in the radial direction of the cage 4 as shown in FIG. For this reason, the cage 4
In this embodiment, since the projections 4b extending in the radial direction are provided at both ends in the axial direction of each hole 4a of the cage 4, each ball is provided. 3 is allowed to move in the radial direction by each protrusion 4b,
It is possible to reduce the thickness dimension of a portion excluding each projection 4b.

By the way, when the dimension of the cage 4 in the thickness direction is reduced, the grooves 1a and 2a can be formed deeper by that much, and especially, the contact load of the ball 3 to the edge of each groove 1a and 2a can be reduced. Durability can be improved. As shown in FIG. 6, the contact load P of the ball 3 is applied to each groove 1a, 2a.
Is added, the major axis length and the minor axis length of the contact ellipse D of the contact portion of the ball 3 in each of the grooves 1a and 2a become longer as the load increases. Therefore, each groove 1a, 2a
The contact ellipse D can be increased as much as the depth of the ball 3 increases, and the allowable amount of the ball 3 against the load can be increased. For example, as shown in FIG. 7, when the characteristics of the prototypes A and B having different major axis lengths of the contact ellipse are compared, at the same maximum contact stress, the load of the prototype B having the major axis of the contact ellipse is longer. It was confirmed that the load was about 1.6 times the load of the prototype A having a short major axis.

As described above, according to the constant velocity universal joint of the present embodiment, the projections 4b provided in the respective holes 4a of the cage 4 allow the balls 3 to move in the radial direction, thereby increasing the thickness of the cage 4. Since the dimension in the vertical direction can be reduced,
Each groove 1a, 2a can be formed deep by that much,
Greater torque can be transmitted. in this case,
Since each of the projections 4b of the cage 4 is formed by partially displacing the edge of the hole 4a in the radial direction, the edge of the hole is deformed by pressing or the like, so that each of the projections 4b is deformed.
Can be easily formed.

FIG. 8 is a first embodiment showing a method of forming the projection of the cage 4. As shown in FIG. That is, as shown in FIG. 8 (a), the die 5 is arranged inside the cage 4 in which the hole 4a is formed, and the punch 6 is pressed against the edge of the hole 4a from the outside of the cage 4 so that the die 5 is pressed. The protrusion 4b is press-formed by the concave mold 5a and the convex mold 6a of the punch 6. Thereby, molding of each projection 4b can be performed very easily.

FIGS. 9 and 10 show a second embodiment of the method of forming the projection of the cage 4. As shown in FIGS. That is, as shown in FIG. 9 (a), a notch 4c extending in the axial direction is formed at the edge of the hole 4a of the cage 4, and both sides of the notch 4c are bent from the broken lines in the figure to the inside of the cage 4 to obtain (a) As shown in FIG. 10 and FIG. 10, a projection 4d projecting in the radial direction of the cage 4 is formed. In this case, as shown in FIG. 9A, if the bent portion of the hole 4a is projected obliquely in the axial direction,
As shown in FIG. 9B, when the protrusion 4d is formed by bending, the end face of the protrusion 4d is formed so as to be linear with the periphery of the hole 4a.

FIGS. 11 and 12 show a third embodiment of the method of forming the projection of the cage 4. FIG. That is, as shown in FIG. 11, two cuts 4e extending in the axial direction are formed at the edge of the hole 4a of the cage 4 at intervals in the circumferential direction, and a portion between the cuts 4e is cut from the broken line in FIG. By bending inward, a projection 4f that projects in the radial direction of the cage 4 is formed as shown in FIG.

FIGS. 13 and 14 show a fourth embodiment of the method for forming the projection of the cage 4. As shown in FIGS. That is, as shown in FIG. 13, a notch 4g extending continuously in the axial direction and the circumferential direction is formed at the edge of the hole 4a of the cage 4, and the notch 4g is formed.
By bending the portion surrounded by the dashed line in the figure from the broken line to the inside of the cage 4, a projection 4h projecting in the radial direction of the cage 4 is formed as shown in FIG.

FIGS. 15 to 18 show an apparatus for manufacturing a cage for the constant velocity universal joint. That is, the cage manufacturing apparatus shown in FIG.
And a plurality of inner molds 11 for molding the inner peripheral surface side of the tubular material 7.

Each of the outer molding dies 10 is arranged in the circumferential direction of the cylindrical material 7, and a concave surface 10a corresponding to the outer peripheral surface of the cage 4 is formed on the inner peripheral surface thereof.

Each of the inner molds 11 is arranged at an interval in the circumferential direction of the tubular material 7 and has a cage 4 on its outer peripheral surface.
A convex surface 11a corresponding to the inner peripheral surface of the above is formed. Each of the inner molds 11 is movably supported in the radial direction by a support member 11b, and the inner peripheral surface thereof is formed in a tapered shape along the axial direction. Further, each of the inner molds 11 and the support members 11b can rotate in the circumferential direction.

In the cage manufacturing apparatus constructed as described above, as shown in FIG. 15, the cylindrical material 7 is moved between the respective molds 10, 11 while the respective inner molds 11 are moved inward in the radial direction. , And a tapered pressing member 12 is inserted inside each inner forming die 11. As a result, as shown in FIG.
1 moves radially outward, and a part of the cylindrical material 7 in the circumferential direction is pressed by each of the inner forming dies 11. Next, as shown in FIG. 17, each inner mold 11 is returned radially inward and rotated by a predetermined angle in the circumferential direction, and each inner mold 11 is moved radially outward again as shown in FIG. By pressing the remaining portion of the cylindrical material 7 in the circumferential direction, the cylindrical material 7 is formed into a shape having a curved peripheral surface.

As described above, according to the cage manufacturing apparatus of the present embodiment, a plurality of inner forming dies arranged in the circumferential direction mutually inside the cylindrical material 7 whose outer peripheral surface side is covered by each outer forming die 10. The cylindrical material 7 is pressed and formed by moving the inner forming dies 11 toward the outside in the radial direction, so that the circumferential surface of the cylindrical material 7 is Can be easily formed into a curved shape along the peripheral surface of the above, which is extremely advantageous in manufacturing the cage 4 of the constant velocity universal joint. In addition, since each of the inner molds 11 is moved radially outward by inserting the pressing member 12, each of the inner molds 11 can be simultaneously moved with a uniform force.

The projections 4b of the cage 4 are formed after the step of forming the cage body by the cage manufacturing apparatus, as shown in FIGS.
Although it can be formed by any of the processing methods shown in FIG. 4, a concave portion and a convex portion for projecting a protrusion are provided in each of the molds 10 and 11 of the cage manufacturing apparatus, and pressure forming is performed by the cage manufacturing apparatus. The protrusions may be formed at the same time. In the step of moving each inner forming die 11 in the circumferential direction of the cylindrical material 7, each inner forming die 11 may be fixed and the cylindrical material 7 may be rotated.

[0032]

As described above, according to the constant velocity universal joint of the first aspect, the dimension of the cage in the thickness direction can be reduced, so that the groove of each rotating body can be formed deep. , Can transmit a larger rotational force.

Further, according to the method of manufacturing a cage for a constant velocity universal joint according to the second aspect, the dimension of the cage in the thickness direction can be reduced, so that the groove of each rotating body can be formed deeply. A large torque can be transmitted. In this case, the projection for allowing the ball to move in the radial direction of the cage can be easily formed by press working or the like, which is extremely advantageous in processing the material and reducing the manufacturing cost.

According to the method for manufacturing a constant velocity universal joint cage of the third aspect, the dimension of the cage in the thickness direction can be reduced, so that the groove of each rotating body can be formed deeply. A large torque can be transmitted. In this case, since the projection for allowing the ball to move in the radial direction of the cage can be easily formed by bending or the like, it is extremely advantageous in processing materials and reducing manufacturing costs.

According to the method of manufacturing a cage for a constant velocity universal joint according to a fourth aspect, in addition to the effect of the second or third aspect, the circumferential surface of the cylindrical material to be the cage is formed along the circumferential surface of each rotating body. The cage can be manufactured more efficiently because it can be easily formed into a curved shape.

According to the apparatus for manufacturing a cage for a constant velocity universal joint according to the fifth aspect, the peripheral surface of the cylindrical material to be the cage can be easily formed into a curved shape along the peripheral surface of each rotating body. As a result, the cage can be manufactured more efficiently.

According to the apparatus for manufacturing a cage for a constant velocity universal joint of claim 6, in addition to the effect of claim 5, since the inner molds can be simultaneously moved with a uniform force, the processing accuracy is improved. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a constant velocity universal joint according to an embodiment of the present invention.

FIG. 2 is a side view of a cage.

FIG. 3 is a sectional view taken along line XX of FIG. 2;

FIG. 4 is a side cross-sectional view of the constant velocity universal joint, showing a state where the rotation axis is inclined.

FIG. 5 is a side sectional view of a main part of the cage.

FIG. 6 is an explanatory view of a contact ellipse acting on a groove.

FIG. 7 is a comparative explanatory view regarding the durability of the groove.

FIG. 8 is a process explanatory view showing a first embodiment in a method of forming a protrusion.

FIG. 9 is a partial side view of a cage showing a second embodiment in a method of forming a projection.

FIG. 10 is a partial cross-sectional view of a cage showing a second embodiment in a method of forming a protrusion.

FIG. 11 is a partial side view of a cage showing a third embodiment in a method of forming a projection.

FIG. 12 is a partial cross-sectional view of a cage showing a third embodiment in a method of forming a protrusion.

FIG. 13 is a partial side view of a cage showing a fourth embodiment in a method of forming a projection.

FIG. 14 is a partial cross-sectional view of a cage showing a fourth embodiment in a method of forming a protrusion.

FIG. 15 is a side sectional view and a sectional view taken along line YY of the cage manufacturing apparatus.

FIG. 16 is a side sectional view and a sectional view taken along the line ZZ of the cage manufacturing apparatus.

FIG. 17 is an explanatory view of the operation of the inner mold.

FIG. 18 is an explanatory view of the operation of the inner mold.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Outer rotating body, 1a ... Groove, 2 ... Inner rotating body, 2a ...
Groove, 3 ... ball, 4 ... cage, 4a ... hole, 4b ... projection,
4c ... notch, 4d ... protrusion, 4e ... cut, 4f ...
Projection, 4g Cut, 4h Projection, 5 Dice, 6
Punch, 7: cylindrical material, 10: outer mold, 11: inner mold, 12: pressing member.

Claims (6)

[Claims] 1. An outer rotating body that rotates integrally with one rotating shaft, an inner rotating body that rotates integrally with the other rotating shaft, a plurality of grooves provided on an inner peripheral surface of the outer rotating body, and an inner rotating body. A plurality of balls respectively engaging with a plurality of grooves provided on an outer peripheral surface of the outer rotating body, and a plurality of balls arranged between the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, each of which holds each ball in a freely rolling manner. And a cage having holes, and a groove of each rotating body is formed so as to be curved in an axial cross-section of each rotating body, thereby holding a swing center of each rotating shaft at a predetermined position. In the constant velocity universal joint as described above, a projection is provided at both ends in the axial direction of each of the holes of the cage, the protrusions being formed such that the edges of the holes are partially offset radially inward or outward. Universal joint. 2. An outer rotating body that rotates integrally with one rotating shaft, an inner rotating body that rotates integrally with the other rotating shaft, a plurality of grooves provided on an inner peripheral surface of the outer rotating body, and an inner rotating body. A plurality of balls respectively engaging with a plurality of grooves provided on an outer peripheral surface of the outer rotating body, and a plurality of balls arranged between the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, each of which holds each ball in a freely rolling manner. And a cage having holes, and a groove of each rotating body is formed so as to be curved in an axial cross-section of each rotating body, thereby holding a swing center of each rotating shaft at a predetermined position. In the method for manufacturing a cage for a constant velocity universal joint as described above, a protrusion protruding radially inward or outward of the cage is formed by partially deforming an edge of each hole of the cage. Cage manufacturing method for constant velocity universal joints. 3. An outer rotating body that rotates integrally with one rotating shaft, an inner rotating body that rotates integrally with the other rotating shaft, a plurality of grooves provided on an inner peripheral surface of the outer rotating body, and an inner rotating body. A plurality of balls respectively engaging with a plurality of grooves provided on an outer peripheral surface of the outer rotating body, and a plurality of balls arranged between the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, each of which holds each ball in a freely rolling manner. And a cage having holes, and a groove of each rotating body is formed so as to be curved in an axial cross-section of each rotating body, thereby holding a swing center of each rotating shaft at a predetermined position. In the method for manufacturing a cage of a constant velocity universal joint as described above, a notch of a predetermined shape is formed at an edge of each hole of the cage, and the periphery of the notch is partially bent to radially inward or outward of the cage. To form a protruding protrusion Constant velocity universal joint method cage fabrication of the symptoms. 4. A mold having a predetermined shape is arranged on each of an outer peripheral surface side and an inner peripheral surface side of the plastic cylindrical material to be the cage, and the inner peripheral surface side mold is moved radially outward. In this way, a part of the cylindrical material in the circumferential direction is pressure-formed, and the mold on the inner peripheral surface side is moved in the circumferential direction of the cylindrical material to form the other part of the cylindrical material in the circumferential direction by pressure. The method for manufacturing a cage for a constant velocity universal joint according to claim 2 or 3, wherein: 5. An outer rotating body that rotates integrally with one rotating shaft, an inner rotating body that rotates integrally with the other rotating shaft, a plurality of grooves provided on an inner peripheral surface of the outer rotating body, and an inner rotating body. A plurality of balls respectively engaging with a plurality of grooves provided on an outer peripheral surface of the outer rotating body, and a plurality of balls arranged between the inner peripheral surface of the outer rotating body and the outer peripheral surface of the inner rotating body, each of which holds each ball in a freely rolling manner. And a cage having holes, and a groove of each rotating body is formed so as to be curved in an axial cross-section of each rotating body, thereby holding a swing center of each rotating shaft at a predetermined position. In the apparatus for manufacturing a cage for a constant velocity universal joint, an outer molding die having a predetermined shape disposed on the outer peripheral surface side of the plastic cylindrical material serving as the cage, and a circumferential direction on the inner peripheral surface side of the cylindrical material. Are arranged at intervals in the radial and circumferential directions of the cylindrical material. Cage apparatus for manufacturing the constant velocity universal joint is characterized in that a plurality of inner molds each movable predetermined shape. 6. An inner peripheral surface of each of the inner molds is formed so as to be inclined toward one side in the axial direction, and a tapered pressing member is inserted between the inner peripheral surfaces of each of the inner molds in the axial direction. 6. The cage manufacturing apparatus for a constant velocity universal joint according to claim 5, wherein each inner forming die is moved radially outward.