JPS5815212B2 - Method for manufacturing barfilt type constant velocity joint cage - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a barfilt type constant velocity joint cage.

More specifically, in a barfilt type constant velocity joint consisting of an inner/row drive member, a cage, and a ball, the structure of the cage, which is a ball holding member interposed between the inner and outer drive members, is simplified; The present invention relates to a method for manufacturing a cage that facilitates molding.

In automobiles with independent suspension and front wheel drive, the working angle of the joint on the wheel side becomes large due to the steering mechanism of the wheel, and therefore a large working angle and constant velocity are required, so a so-called constant velocity joint is used. used.

The barfilt type is already known as this type of constant velocity joint.

As shown in FIG. 6, this bar filter type constant velocity joint consists of an inner/outer driving member 1.2, a ball 9, and a member 1.
It consists of a cage 10 held between two.

The outer circumferential surface 3 of the inner drive member 2 is formed into a partially convex spherical shape, and on the circumference thereof there are ball rolling grooves 4 radially extending in the axial direction, and on the inner circumference of the outer drive member 1 there are Rolling groove 4...
...corresponding rolling grooves 5... are arranged in stages in the axial direction, and a cage 10 is interposed between the members 1 and 2.

The outer diameter section 11 of the cage 10 fits into the inner diameter section 6 of the outer drive member 1, is frusto-conical, and partially provided with a convex spherical surface 12 to enable articulation.

In addition, the inner diameter portion 13 is formed into a concave spherical surface corresponding to the outer peripheral convex spherical surface 3 of the inner drive member 2, and allows the inner drive member 2 interposed and held therein to articulate.

And on the circumferential surface of the cage 100, there are windows 14 that penetrate inside and outside...
... is drilled, and the ball 9 passes through the window 14 into the interior of the window 14.
A drive shaft 8 facing the rolling grooves 4, 5, . The angle formed by the driven shaft (not shown) connected to the drive shaft 1 is held within a plane that divides the angle into three equal parts.

And cage 1 of this kind of barfilt type constant velocity joint
The details of the cage 10 are shown in FIGS. 7 to 9. As is clear from FIGS. A large convex spherical surface 12 with a radius R is formed over the entire surface, and a concave spherical surface 13 with a radius r smaller than the above R is formed over the entire inner peripheral surface 13.
is matched with the radial convex spherical surface 3 between the rolling grooves 4 of the inner drive member 2.

The axial tip portion 13-1 of this concave spherical surface 13 protrudes toward the center along r, and this portion 13-1 is provided between each window 14, and extends from the protruding tip portion 13-1 in a direction perpendicular to the axis. The cage 10 is formed into a cylindrical shape by providing a support portion 13-2 and merging with the insertion side of the inner drive member 2 which opens 15 toward the end surface.

That is, in order to obtain an insertion opening into which the member 2 is inserted, the cage 10 has an opening 15 formed in one end face with a large diameter and deep enough to reach the window 14, and a concave spherical surface 13 is formed inside this opening 15 in the axial direction.
The tip 13-1 of this concave spherical surface 13 on the opening 15 side is connected to the opening 15.
This portion is a protruding step portion that protrudes radially toward the center.

The method for manufacturing the cage 10 described above is as shown in FIG. 10 (the cut material W shown in FIG. Next, this is forged and extruded backward to obtain a cup-shaped material W2, and a round hole W4 is punched in the bottom.
A raw material W3 having a formed thereon is obtained.

The material W3 thus obtained is a substantially linear thick-walled cylindrical body having a through hole in the axial direction, and is machined as shown in FIG. 11 to obtain the cage 10.

That is, the linear thick wall part a of the inner diameter part is cut so that the inner part of the outer diameter part forms a concave spherical surface and a convex spherical surface, respectively, and radial windows are bored by drilling, broaching, etc., and then a concave part is formed. The tip of the spherical surface should be removed only in the area between the windows (this part d is counterbore cut).

Then, the cage 10 is obtained by cutting the inner etf of the upper and lower (front and rear) end surfaces.

As is clear from this, in the past, the cage was formed from a straight, thick-walled cylindrical body, which required an extremely large amount of machining, and a lot of cutting work. Because of the protruding structure, molding of the step part is required in addition to machining the inner and outer diameters, which requires an extremely large number of man-hours, and the molding is cumbersome and complicated, which inevitably increases the cost of manufacturing the cage and reduces the overall cost of the constant velocity joint. It also becomes more expensive.

As is clear from the above, since there is a large amount of machining allowance, in addition to the above,
It is also unfavorable from a material economic point of view.

In view of the above-mentioned problems in manufacturing cages of this type of barfilt type constant velocity joint, the present inventors have created the present invention to effectively solve the problems.

In particular, in the above-mentioned cage, the present inventors have found that there is no need to protrude the tip of the concave spherical surface of the cage inner diameter, and to counterbore the end face of this on the side of the opening for inserting the inner drive member into a flat surface inside the opening. In this case, it is sufficient that the inner driving member can be fitted from the opening through the ball rolling groove, and the concave spherical surface can be fitted with the outer circumferential convex spherical surface of the inner driving member to perform joint movement, and to prevent movement in the axial direction. It is good if it can be suppressed (the above function can be performed sufficiently without machining the overhanging protrusion inside the opening of the concave spherical surface, and there is no problem with the function of the constant velocity joint, the window part is a ball) It is sufficient that the inner and outer spherical surfaces can be formed in advance, and it is easy to form them in conjunction with the above. The present invention was created by focusing on the fact that

The object of the present invention is to forge and extrude a raw material to form a cup-shaped raw material, and to form a cup-shaped raw material on the inner wall of the cup-shaped raw material with protrusions forming a part of a concave spherical surface in a radial shape. The insertion opening side is punched and formed into a chrysanthemum-shaped hole leaving a protruding end, and the outer periphery of the portion opposite to the opening side is swaged to form a substantially spherical shape, and machined as necessary. To provide a method for manufacturing a constant velocity joint cage.

Therefore, the object of the present invention is to eliminate the need for machining to form the projection on the insertion opening side of the concave spherical surface, and to form a spherical surface by making the thickness of the material as thin as possible and swaging it. Therefore, the cutting allowance can be set as small as possible, simplifying machining, reducing the number of man-hours, dramatically improving mass production, and reducing the cost of this type of cage. To provide a cage for a constant velocity joint that contributes to cost reduction of the constant velocity joint.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

1 to 3 show a plan view, a sectional view taken along the line 2-2, and a perspective view of the cage of the barfilt type constant velocity joint according to the present invention, and FIG. 4 shows an explanatory diagram showing the manufacturing process in the order of steps.
FIG. 5 is an explanatory longitudinal sectional side view showing the portion to be machined.

Reference numeral 20 denotes a cage, the main body 21 of which has a cylindrical shape with an opening in the axial direction, and the outer peripheral surface 22 is a large circular arc with a radius R centered at a point offset by a predetermined amount from the axial center of the ball window 25. , the part near the driving shaft side (upper part in FIG. 2) is formed as a partial real spherical surface 23, and the part near the driven shaft (lower part in FIG. 2) is formed by a small circular arc with an outer diameter smaller than this.

The inner circumferential surface 24 is a concave spherical surface having approximately the same arc as the convex spherical surface of the outer circumferential surface 22.

Between the inner and outer circumferential surfaces of the main body 21, a plurality of ball windows 25, for example, six ball windows 25, are bored radially through the wall at equal angular intervals.

The opening 26 on the driven shaft side becomes the opening 27 on the drive shaft side due to the decrease in the diameter of the inner peripheral part 24 as the diameter of the outer peripheral part 22 gradually decreases.
That is, it is formed to have a smaller diameter than the insertion opening of the inner drive member 2.

A portion of the inner circumferential surface 24 between the windows 25 . Article 28...
... are formed radially, and the end portion 28-1 of the protrusion 28 extends flush with the end surface 29 of the cage 20 having the opening 27.

Therefore, as shown in FIG. 1, the plane of the opening 27 is approximately in the shape of a picture-shaped hole, with protrusions 28 radially formed on the inner diameter, flush with this end surface.

The inner surfaces of the protrusions 28, that is, the inner surfaces 30 of the peaks protruding toward the center, are concave spherical surfaces with the same radius r that are continuous with the small arc concave spherical surface 24-1 on the driven shaft side of the inner circumferential surface 24. are formed, and both axial ends 30-1 of this concave spherical inner surface 30 are formed.
30-2 restricts the movement of the convex spherical surface 3 of the inner drive member 2 in the axial direction, and the concave spherical inner surface 30 allows its articulation.

The convex spherical surface 23 of the outer circumferential surface 22 allows joint motion within the outer drive member 1, and since the other portions of the outer circumferential surface 22 have smaller arcs than this, the inner circumferential surface of the outer drive member during the above joint motion. Don't interfere.

As described above, the window 25 that engages the convex spherical surface of the inner drive member 2
... The insertion length 27 side end portion 28-1 of the protrusion 28 forming the concave spherical surface 30 between the openings 27 and the end surface 29 on the opening 27 side is not provided with a step on the inside in the axial direction with respect to the opening 27. A protrusion is formed on the inner diameter portion flush with the protrusion, forming an image-shaped hole as shown in FIG.

The inner driving member 2 is inserted because the convex spherical surface 3 that fits into the concave spherical surface 30 has a ball rolling groove 4 in the axial direction. By matching the end portion 28-1, it can be easily inserted in the axial direction, and by rotating it after insertion, the convex spherical surface 3
and the concave spherical surface 30 are easily fitted together.

The axial movement of the inner drive member 2 is restricted at both axial ends 30-1 and 30-2 of the concave spherical surface 30.

In addition, the relationship with the outer driving member 1 is such that the joint movement is performed on the convex spherical surface 23 as described above, and the member 1 during joint movement is performed on the small arc portion.
Prevent interference with the inner surface of the

In this way, it functions as a cage for the constant velocity joint.

Next, the cage manufacturing method described above will be explained in detail with reference to FIGS. 4 and 5.

FIG. 4 shows the manufacturing method of the present invention in order of steps.

FIG. 4A shows the cut material W2o, which is compressed by upsetting to expand the width and densify the internal structure, and the upholstered material W2. get.

Next, the above upsetting material W21 is formed into a cup-shaped material W22 by forging and extrusion molding.

During this forming process, the tip of the punch is shaped like a leaf-shaped punch with a curved outer circumferential surface and a radially protruding surface. Projections W22 having a concave spherical surface W26 formed on the inner surface are formed radially around the inner bottom.

This is shown in Figure 4C.

The closed end W25 of the above material W22 is punched and formed with a punch having radial concave portions on the outer periphery to form a material W29 having an opening W28. A protrusion W3o corresponding to the projection W3o is formed.

Next, the material W29 is swaged and reduced in diameter centering on the side that does not have the protrusions W22, that is, the opening W24 side, and the inner and outer surfaces are approximately the same arc convex spherical surface W3□ and a concave spherical surface. W32 is formed to obtain the material W33 shown in FIG. Shape.

In the above, the swaging process is performed to form the convex spherical surface W31.
In order to form the concave spherical surface w32, it is possible and necessary to make the thickness of the material as close as possible to the final dimension during the forging and extrusion molding.

The thus obtained material W35 is as shown in FIG. 5, and has a thin machining allowance Wa on the outer periphery, a thin machining allowance ■t on the inner periphery, a machining allowance We on the end face on the opening W24 side, and a window W3.
The thin machining allowance Wd on the inner circumference of No. 4 will be left as a balance,
This portion is removed by cutting or the like using machining to obtain the cage 20 described above.

As described above, the desired cage 20 can be obtained with the minimum necessary machining.

As is clear from the above description, according to the present invention, the material is formed into a cup shape by forging extrusion so that the inner circumferential wall is provided with a protrusion having a concave spherical surface, and the closed end is formed into a leaf-shaped hole shape with the protrusion remaining. The material is punched and formed, and then swaged to reduce the diameter and form into a spherical shape. This process allows the material to be thinned close to the final dimensions, reducing the machining allowance as much as possible, making it easier for subsequent machining. becomes simpler and easier.

Therefore, compared to the conventional spherical cutting of a straight cylindrical material, the machining process is dramatically simpler and easier, and this type of cage can be easily obtained with a minimum of man-hours, and mass production of the same is possible.
This is an excellent product that contributes to cost reduction, which in turn contributes to simplifying the production of this type of constant velocity joint and reducing cost.

In addition, it is advantageous in terms of material economy by reducing the machining allowance as much as possible, and since the material can be made thinner, window processing can also be performed by punching. Forming can also be done by simply shaping the punch into a picture shape and adding swaging processing. It exhibits various features such as being simple and the manufacturing method itself is rational, and is extremely practical.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a plan view of a cage according to the present invention, FIG. 2 is a sectional view taken along line 2-2 in FIG. 1, FIG. 3 is a perspective view, and FIGS. F is an explanatory diagram showing the manufacturing method according to the present invention in the order of steps, FIG. 5 is an enlarged cross-sectional view of the material before final processing, FIG. 6 is a longitudinal cross-sectional side view of a barfilt type constant velocity joint, and FIG. 7 is a conventional cage. 8 is a sectional view taken along the line 8-8 in FIG. 7, FIG. 9 is a perspective view of the same, and FIG. 10A
The following is an explanatory diagram showing the conventional manufacturing method in the order of steps, No. 11
The figure is an enlarged cross-sectional view of the same material before final processing. In the drawing, 20 is a cage, 22, 23 is a convex spherical surface, 24 is a concave spherical surface, 25 is a window, 27 is an opening, 28 is a protrusion, 30 is a concave spherical surface, W2o is a material, W27 is a protrusion, W2. is a cup-shaped material, W28 is a drawing hole, W30. W32 is a swaging-processed spherical surface.

Claims (1)

[Claims] 1. A first step of forging and extruding the upsetting material into a cup shape, and also radially forging and extruding protrusions with a concave spherical inner surface around the inner bottom of the closed end, and the forming material obtained in the first step. A second step of punching and forming the closed end into a chrysanthemum-shaped hole leaving the end of the protruding portion, and swaging the molded material obtained in the second step to reduce the diameter of the outer surface. and a third step of forming the inner surface into a convex spherical surface and a concave spherical surface of approximately the same arc.