JPH0988994A - Yoke for shaft coupling, manufacture thereof and elastic shaft coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To aim at the promotion of low-unit cost of production by facilitating the manufacture and assembly of individual constituent elements, in this shaft coupling yoke. SOLUTION: This is a tubular yoke 5 being installed in the end of one side shaft of a universal joint 2 connecting two concentric shafts, two wall parts 51 and 52 at the 180 deg. opposed position of a peripheral surface are formed almost in parallel with each other, while two notches 55 and 56 being opened toward the shaft end side are formed in each of these parallel wall parts 51 and 52. When two notches 55 and 56 are formed, it comes to blanking to these wall parts 51 and 51, whereby a special punch and a support jig become useless, and simultaneously operations are made simply performable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yoke for use in a shaft coupling that connects two coaxial shafts, a method for manufacturing the yoke, and a state in which the two coaxial shafts have elastic play in the rotational direction. To an elastic shaft coupling that is coupled to the.

[0002]

2. Description of the Related Art FIG. 8 shows a steering mechanism of a general automobile. In the figure, 50 is a handle, 51 is a steering shaft, 52 is an input shaft of a steering gear device (power steering device), 53 and 54 are cross pin type universal joints, and 55 is an elastic shaft joint.

Two universal joints 53, 54
Each of the one-side yokes 53a, 54a is formed in a cylindrical shape, and two plate pieces facing each other by 180 degrees are projectingly provided at one shaft end of the one yoke 53a, 54a. A through hole is formed. This yoke is generally manufactured by punching out unnecessary portions (portions that avoid interference with the mating yoke) in a cylindrical pipe, or by punching a flat plate into a required shape and then bending it into a cylindrical shape. Then, it is manufactured by welding the butted parts.

The elastic shaft joint 55 cuts off the vibration transmission from the wheel to the handle 50 and gives the handle operation an elastic play. Details of the elastic shaft joint 55 are shown in FIGS. 9 and 10. In the figure, 56 is a cylinder shaft, 57 is a shaft, 58 is a damper, and 59 is a stopper pin.

The cylindrical shaft 56 is formed integrally with one yoke 54a of the lower universal joint 54 in FIG. 8, and at the end of the cylindrical shaft 56, two through holes 56a penetrating in the diametrical direction, 56a is formed. Shaft 57
Is integrally formed with one yoke 53a of the upper universal joint 53 in FIG. Damper 58
Is a structure in which a cylindrical elastic body 58c such as rubber is baked between a metal inner cylinder 58a and an outer cylinder 58b. The inner cylinder 58a of the damper 58 is externally fitted and press-fitted to the shaft 57, and the outer cylinder 58b is internally fitted and press-fitted to the cylinder shaft 56. The stopper pin 59 is fixed such that the intermediate portion thereof penetrates the shaft 57 and the damper 58 in the diametrical direction, and the projecting both ends thereof are fixed to the cylindrical shaft 56.
Are inserted into the two through holes 56a, 56a via required clearances.

The operation of such an elastic shaft coupling 55 will be described. When the shaft 57 rotates, the inner cylinder 5 of the damper 58
8a and the stopper pin 59 rotate integrally, and elastic twist is given to the elastic body 58c integrated with the inner cylinder 58a. When this twist exceeds a certain amount, the outer cylinder 58b of the damper 58 starts rotating, and along with this, the cylinder shaft 56 integrated with the outer cylinder 58b also starts rotating. After this, shaft 5
7 and the stopper pin 59 integrated with the through hole 56 of the cylindrical shaft 56.
When hitting the hole edges of a and 56a, the shaft 57 to the cylinder shaft 5
The rotational force is transmitted rigidly to 6 directly. That is, as a feeling of operation, there is a play at the start of rotation, and an elastic reaction force gradually responds as the rotation angle increases, and finally there is a rigid response. Therefore, the handle operation is easy.

[0007]

By the way, the above-mentioned conventional universal joint yoke is manufactured by the above-mentioned two kinds of manufacturing methods, but each has the following problems. There is room for improvement.

First, in the case of manufacturing from a cylindrical pipe, in order to obtain a pair of plate pieces, a region having a relatively large area between them is punched out. It is necessary to make the shape of the punch's cutting edge and the shape of the receiving jig special along the curved surface, and if the curvature of the curved surface is different, it is necessary to prepare various types according to it. It is pointed out that the cost is high.

On the other hand, in the case of manufacturing from a flat plate, punching can be easily performed on the flat plate, but welding work unrelated to the flat plate is required, and the work efficiency is low, such as combining unrelated processes. Therefore, it is pointed out that the manufacturing cost is high in relation to productivity.

Further, the above-mentioned conventional elastic shaft joint has a function of giving elastic play at the initial stage of rotation and a function of rigidly transmitting power as the rotation angle increases. Many configurations are needed to realize. On the other hand, in recent years, simplification of the configuration and cost reduction have been required, but the conventional structure has a limit, and there is room for improvement.

Therefore, it is an object of the present invention to facilitate the production and assembly of each component of a shaft coupling yoke and to reduce the cost.

Therefore, it is an object of the present invention to facilitate the production and assembly of each component of an elastic shaft coupling and to reduce the cost.

[0013]

A first shaft coupling yoke of the present invention is a cylindrical one provided at the shaft end of one shaft of a shaft coupling for connecting two coaxial shafts. 180 around the surface
The wall portions at opposite positions are formed substantially parallel to each other, and each parallel wall portion is formed with a notch that opens toward the shaft end side.

The second yoke for a shaft coupling of the present invention is of a cylindrical shape provided at the shaft end of one shaft of a shaft coupling for connecting two coaxial shafts, and has 180 ° opposite circumferential surfaces. The wall portions at the positions are formed substantially parallel to each other, and the wall portions at positions facing each other by 180 degrees on the peripheral surface orthogonal to the wall portions are formed in an arch shape, and the parallel wall portions are directed toward the shaft end side. A notch is formed to open it.

The third shaft coupling yoke of the present invention is a cylindrical one provided at the shaft end of one shaft coupling of the two shaft couplings for connecting two coaxial shafts, and has a circumference on the one shaft end side. The wall portions of the surfaces facing each other by 180 degrees are formed substantially parallel to each other, and each parallel wall portion is formed with a notch that opens toward the one shaft end side, and the other shaft end side. Has a cylindrical surface.

The method for manufacturing a yoke for a shaft coupling according to the present invention comprises the steps of compression-molding the wall portions of the cylindrical member at positions opposite to each other by 180 degrees, so that the wall portions are substantially parallel to each other. Punching each of the parallel wall portions from the thickness direction to provide a notch that opens toward the shaft end side in the wall portion.

The elastic shaft coupling of the present invention couples two coaxial shafts in a state having elastic play in the rotational direction, and comprises the third shaft coupling yoke and the yoke of the third shaft coupling. A shaft body that is inserted into the inner circumference in a non-contact state and has an outer shape that is similar to the outer shape of the yoke, and is interposed between the outer peripheral surface of the cylindrical portion of the shaft body and the inner peripheral surface of the cylindrical portion of the yoke. And a cylindrical damper.

As described above, in the first to third yokes of the present invention, the cylindrical wall portions are provided on their peripheral surfaces and are parallel to each other.
Since the wall is provided with a notch for avoiding interference with another yoke paired with the yoke, when the notch is formed, punching is performed for each parallel wall portion, and a special punch or receiving member is provided. No jig is required and the work can be done easily.

Further, in the method of manufacturing the yoke of the present invention, since the cylindrical member is processed, the processing such as welding becomes unnecessary in addition to the above-mentioned processing.
Work efficiency increases.

Further, in the elastic shaft coupling using the third yoke of the present invention, when the shaft body is rotated, the damper elastically twists and transmits the rotational force to the yoke, but as the rotation angle of the shaft body increases. The shafts come into contact with the mutually parallel walls of the yoke, whereby the torque is directly and rigidly transmitted to the yoke. That is, in the elastic shaft coupling of the present invention, the conventional stopper pin is unnecessary, so that it is not necessary to provide a portion for holding the stopper pin or a portion for abutting the stopper pin, and thus the shape can be simplified and the number of assembling steps can be reduced.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the embodiments shown in FIGS. 1 to 5
1 relates to an embodiment of the present invention, FIG. 1 is an exploded perspective view showing a joint portion of a steering mechanism of an automobile, and FIG.
2 is a cross-sectional view of the elastic shaft joint cut in the vertical direction, FIG. 3 is a cross-sectional view of the elastic shaft joint cut in the horizontal direction, and FIG. 4 is a cross-sectional view taken along line (4)-(4) of FIG. FIG. 5 shows (5) of FIG.
-(5) It is an arrow view of a cross section.

In the figure, 2 is a cross pin type universal joint, and 3 is an elastic shaft joint.

The universal joint 2 comprises a first yoke 4, a second yoke 5 and a cross pin 6.

The first yoke 4 is made of a general one in which a pair of plate pieces 41 and 42 opposed to each other by 180 degrees are provided on one axial end side of the cylindrical main body. The plate pieces 41 and 42 are curved with the same curvature as that of the cylindrical body, and coaxial through holes 43 and 44 are bored in their respective predetermined positions in the thickness direction.

The second yoke 5 has flat wall portions 51 and 52 formed by forming wall portions at positions opposite to each other by 180 degrees on the circumferential surface of approximately half the axial direction so as to be flat wall portions 51 and 52, and are orthogonal to the flat wall portions 51 and 52. The wall portions of the circumferential surface facing each other at 180 degrees are formed in an arch shape to form curved wall portions 53 and 54. The above-mentioned flat wall portions 51, 52 are formed with substantially U-shaped notches 55, 56 that open toward the shaft end side.
Through holes 57 and 58 that are coaxial with each other are formed in predetermined positions of the holes 3 and 54 in the thickness direction. In addition, the notch 55,
56 is for avoiding interference with the first yoke 4.
The peripheral surface of the second half of the second yoke 5 in the axial direction is formed into a cylindrical shape, and this portion is referred to as a cylindrical portion 59.

The cross pin 6 is well known and is 18
The two shaft ends at the 0 ° facing position are fitted into the through holes 43 and 44 of the first yoke 4 via bearings (not shown), and the remaining 180
Two shaft ends at opposite positions are fitted into the through holes 57 and 58 of the second yoke 5 via bearings (not shown).

The elastic shaft coupling 3 includes a second yoke 5 of the universal joint 2, a shaft 7 formed in an outer shape similar to the inner peripheral shape of the second yoke 5, and between the second yoke 5 and the shaft 7. And a damper 8 disposed in the.

The shaft 7 is composed of a cylindrical shaft body, and notch-shaped flat surfaces 71 and 72 which are parallel to each other are provided at positions 180 degrees opposite to each other on the peripheral surface of the tip end thereof. The flat surfaces 71, 72 are arranged to face the inner surfaces of the flat wall portions 51, 52 of the second yoke 5 with a required gap.

The damper 8 is made of an elastic body such as a cylindrical rubber, the outer peripheral surface of which is the inner peripheral surface of the cylindrical portion of the second yoke 5, and the inner peripheral surface of which is the outer peripheral surface of the cylindrical portion of the shaft 7. Are bonded to each other and are in a state of being compressed in the radial direction.

Thus, in the elastic shaft coupling 3 of the present invention,
Since the conventional stopper pin is eliminated, it is not necessary to provide a portion for holding the stopper pin or a portion for contacting the stopper pin, so that the shapes of the second yoke 5 and the shaft 7 can be simplified and the number of assembling steps can be reduced.

Next, a method of manufacturing the second yoke 5 of the universal joint 2 which also serves as a part of the elastic shaft coupling 3 will be described.

First, a cylindrical pipe is prepared. A receiving jig having a substantially rectangular cross section is inserted into the inner circumference of the pipe, and the wall portion of the pipe at a position facing 180 ° on the peripheral surface is compression-molded by drawing or pressing to form the wall portion. The flat wall portions 51 and 52 are substantially parallel to each other. Then, the flat wall portions 51 and 52 are punched out in the thickness direction to form U-shaped notches 55 and 56 that open toward the shaft end side. After that, through holes 57 and 58 for mounting the cross pin 6 are formed by punching out predetermined positions of the curved wall portions 53 and 54 of the pipe from the thickness direction.

These processes are common operations and can be performed continuously, and since the operations themselves are simple, the work efficiency is good and the productivity is improved. Therefore, the manufacturing cost can be reduced. In particular, the second yoke 5 can reduce the number of manufacturing steps as compared with the conventional example in which the plate body is bent and welded.

Next, the operation of the elastic shaft coupling 3 will be described. When the shaft 7 is rotated, the damper 8 is elastically twisted and the rotational force is transmitted to the second yoke 5. As the rotation angle of the shaft 7 gradually increases, the flat surfaces 71 and 72 at the tip of the shaft 7 become flat wall portions 51 and 5 of the second yoke 5.
As a result, the rotational force is directly and rigidly transmitted to the second yoke 5. That is, the flat surfaces 71 and 72 at the tip of the shaft 7 function as conventional stopper pins.
Further, the damper 8 absorbs and damps vibrations from the second yoke 5 to the shaft 7 in the longitudinal direction of the shaft 7 and in the direction perpendicular thereto when the shaft 7 is initially rotated or not rotated.

It should be noted that the present invention is not limited to only the above embodiment, and various applications and modifications are conceivable.

(1) The damper 8 of the elastic shaft coupling 3 is made of only the above-mentioned elastic body, and a structure in which metal inner and outer rings are bonded to the inner and outer peripheral surfaces of the elastic body made of cylindrical rubber or the like. Can be

(2) In the above embodiment, the second yoke 5 of the cross pin type universal joint 2 is used as a part of the constituent elements of the elastic shaft coupling 3, but an independent component unrelated to the universal joint 2 is used. May be used.

(3) In the second yoke 5, the curved wall portions 53 and 54 are also formed as flat wall portions parallel to each other,
The cross section can be square.

(4) The shaft 7 of the elastic shaft coupling 3 is provided with notched flat surfaces 71 and 72 which are parallel to each other at positions opposite to each other by 180 degrees on the circumferential surface of the tip end thereof, and thus the cross section of the tip end of the shaft 7 is formed. Is almost oval,
Instead of forming the flat surface, tapered surfaces 73 and 74 are provided on the end edges of the flat surfaces 71 and 72 as shown in FIG. 6, and the inner surfaces of the flat wall portions 51 and 52 of the second yoke 5 are rotated as the shaft 7 rotates. The state of contact may be surface contact. Alternatively, the entire surface projecting in a mountain shape may be a gentle curved surface, and the cross section of the tip of the shaft 7 may be an egg shape.

(5) In the second yoke 5, as shown in FIG. 7, the distance W between the inner surfaces of the two flat wall portions 51, 52.
Is set to be equal to or slightly larger than the outer diameter dimension of the shell of the shaft end bearing of the cross pin 6, the remaining portions 51a and 52a of the flat wall portions 51 and 52 can be secured as holding portions for the shaft end bearing. That is, since the holding portion and the through holes 57 and 58 provided in the curved wall portions 53 and 54 can increase the margin of the shaft end bearing of the cross pin 6, the cross pin 6 is fitted at the time of mounting. Even if the posture is slanted, it is easy to correct it to a proper posture, which can contribute to the improvement of the overall assembling accuracy. Moreover, as a result, the wall thickness of the second yoke 5 can be set as thin as the minimum required dimension for maintaining the required strength. When thinned in this way, the second
Processing of the flat wall portions 51 and 52, processing of the notches 55 and 56, and processing of the through holes 57 and 58 can be further simplified when the yoke 5 is manufactured.

(6) In the above embodiment, the second yoke 5 of the universal joint 2 is also used as a part of the constituent elements of the elastic shaft coupling 3, but the cylindrical portion 59 is omitted in the second yoke 5. Then, it is possible to provide a structure having only the original function of the yoke. Such a yoke is also included in the present invention.

[0042]

According to the yokes of claims 1 to 3,
When the notch is formed, since the cylindrical wall portions are provided on the peripheral surface and are parallel to each other, and the wall portion is provided with a notch for avoiding interference with another yoke paired with the yoke. By punching parallel wall parts, no special punch or receiving jig is required, and the work can be performed easily.

In the method of manufacturing a yoke of the present invention, since the cylindrical member is processed, in addition to the above, processing such as welding is unnecessary, so that the work efficiency is increased and the production is improved. It is possible to contribute to the reduction of manufacturing cost by improving the productivity.

In the elastic shaft joint using the yoke according to claim 3 of the present invention, the conventional stopper pin is not necessary, so that it is not necessary to provide a portion for holding the stopper pin or a portion for abutting the stopper pin, thereby simplifying the shape. Also, the number of assembling steps can be reduced, the manufacturing cost can be reduced as compared with the conventional example, and the product price can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a joint portion of a steering mechanism portion of an automobile according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the elastic shaft coupling of FIG. 1 taken in a vertical direction.

FIG. 3 is a cross-sectional view of the elastic shaft coupling cut laterally.

FIG. 4 is an arrow view of a cross section taken along line (4)-(4) in FIG. 2;

5 is a cross-sectional view taken along the line (5)-(5) of FIG.

FIG. 6 relates to a modified example of the shaft of the elastic shaft coupling, and FIG.
Figure corresponding to

FIG. 7 is a vertical cross-sectional side view at a cross pin position according to a modification of the second yoke.

FIG. 8 is a side view showing a general steering mechanism section of an automobile.

FIG. 9 is a vertical sectional side view of a conventional elastic shaft coupling.

FIG. 10 is a vertical sectional front view of a conventional elastic shaft coupling.

[Explanation of symbols]

 2 Cross-pin type universal joint 3 Elastic shaft joint 4 Universal joint first yoke 5 Universal joint second yoke 51, 52 Second yoke flat wall portion 53, 54 Second yoke curved wall portion 55, 56 Flat wall portion Notch 59 Cylindrical part of second yoke 6 Cross pin of universal joint 7 Shafts of elastic shaft joint 71, 72 Flat surface of shaft 8 Damper of elastic shaft joint

Claims (5)

[Claims] 1. A cylindrical yoke provided at the shaft end of one shaft of a shaft coupling that connects two coaxial shafts, wherein the wall portions of the peripheral surface at 180-degree opposite positions are formed substantially parallel to each other. In addition, the yoke for a shaft coupling is characterized in that notches that open toward the shaft end side are formed in the respective parallel wall portions. 2. A cylindrical yoke provided at the shaft end of one shaft of a shaft coupling for connecting two coaxial shafts, wherein the wall portions of the peripheral surface at 180 ° opposite positions are formed substantially parallel to each other. The wall portion of the peripheral surface orthogonal to the wall portion at a position opposed to 180 degrees is formed in an arch shape, and each parallel wall portion is formed with a notch opening toward the shaft end side. A yoke for a shaft coupling characterized by the following. 3. A cylindrical yoke provided at the shaft end of one shaft of a shaft coupling for connecting two coaxial shafts, wherein a wall portion of the peripheral surface on the one shaft end side at a 180-degree opposite position is provided. They are formed substantially parallel to each other, and each of the parallel wall parts has a notch that opens toward the one shaft end side,
A yoke for a shaft coupling, wherein the peripheral surface on the other shaft end side is formed in a cylindrical shape. 4. A step of making the wall portions of the cylindrical member facing each other 180 degrees on the peripheral surface of the cylindrical member to be substantially parallel to each other by compression molding, and the respective parallel wall portions from the thickness direction. A step of providing a notch that opens toward the shaft end side in the wall portion by punching, and a method for manufacturing a yoke for a shaft coupling, comprising: 5. An elastic shaft coupling that connects two coaxial shafts in a state having elastic play in the rotation direction, wherein the yoke according to claim 3 and the inner circumference of the yoke are not in contact with each other. And a cylindrical damper inserted between the outer peripheral surface of the cylindrical portion of the shaft and the inner peripheral surface of the cylindrical portion of the yoke. And an elastic shaft coupling including: