JP2547354Y2 - Constant velocity universal joint for steering - Google Patents

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 for connecting a steering shaft to a steering gear in an automobile steering system.

[0002]

2. Description of the Related Art Generally, an automobile is equipped with a steering device for controlling a traveling direction. This steering device is composed of a steering wheel provided in the driver's cab, a steering shaft connected to the steering gear, a steering gear, and a link mechanism communicating with the front wheels. By turning the front wheels to the right or left via the vehicle, the traveling direction of the vehicle is controlled.

Conventionally, in the above-mentioned steering apparatus, as a joint for connecting a steering shaft to a steering gear, a cross joint for transmitting rotational torque via a cross-shaped spider has been widely used. This is because the cross joint has no joint play and can smoothly transmit power.

[0004]

However, in the steering apparatus in which the steering shaft is connected to the steering gear via a cross joint, the operating angle of the steering shaft with respect to the steering gear is too small because the operating angle of the cross joint is small. I can't take it big. Therefore, the steering shaft is divided into a main shaft, one end of which is connected to the steering wheel, and an intermediate shaft, one end of which is connected to the steering gear through the cross joint. , The operating angle of the steering shaft with respect to the steering gear is increased.

However, such a structure has a disadvantage that the shape of the steering shaft is complicated and two joints are required, so that the number of parts is increased and the weight is increased.

Therefore, there is a means that uses a constant velocity universal joint that transmits a rotational torque through a plurality of balls, instead of the above-mentioned cross joint that connects the steering shaft to the steering gear. That is, when the constant velocity universal joint is used for connecting the steering shaft and the steering gear, the operating angle of the constant velocity universal joint is large,
The operating angle of the steering shaft with respect to the steering gear can be increased, which eliminates the need to divide the steering shaft into a main shaft and an intermediate shaft and connect them via a joint, as described above. Simplification and weight reduction.

However, it is important that a joint used for a steering device of an automobile has no joint play so that smooth power transmission can be performed. However, there is no constant velocity universal joint that satisfies such performance. It is a fact. That is, in the conventional constant velocity universal joint, the constituent members such as the inner ring, the outer ring, the ball, and the gauge are formed of a metal material. In the constant velocity universal joint in which the constituent members are formed of the metal material, Since no interference can be given to the ball, joint play occurs due to the clearance between the inner and outer rings and the ball, and smooth power transmission was impossible.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a constant velocity universal joint for steering capable of transmitting power smoothly. The challenge is to eliminate the gap between the inner and outer races and the ball and to eliminate joint play.

[0009]

The present invention has solved the problem by employing a fiber-reinforced composite material as a material of at least the outer race of the main constituent members.

In other words, the constant velocity universal joint for steering according to the present invention has an inner ring in which a predetermined number of guide grooves are formed in the axial direction on the spherical outer peripheral surface, and the same number of guide grooves as the inner ring on the spherical inner peripheral surface. ,
Similarly, there is an outer ring formed with a guide groove extending in the axial direction, a plurality of balls interposed between the guide grooves of the inner and outer rings to transmit torque, and a gap between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring. Consisting of a gauge to hold the ball, at least the outer ring of the constituent members is molded from a fiber-reinforced composite material,
The ball is provided with an interference by utilizing the elasticity of the fiber reinforced composite material.

[0011]

According to the present invention, at least the outer ring is formed of a fiber-reinforced composite material, and the ball is provided with an interference by utilizing the elasticity of the fiber-reinforced composite material. Since it becomes negative, there is no joint play.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of a constant velocity universal joint for steering according to the present invention. The constant velocity universal joint for steering includes an inner ring 1, an outer ring 2, a ball 3, and a gauge 4.

The inner race 1 is spline-coupled to the end of the steering shaft 5, and a predetermined number, for example, six, of guide grooves 1a are formed in the spherical outer peripheral surface in the axial direction in the circumferential direction and the like.

The outer race 2 is formed of a fiber-reinforced composite member (for example, fiber-reinforced plastic) reinforced with carbon fiber or the like, and is spline-coupled to a steering gear (not shown). Guide grooves 2a of the same number as the guide grooves 1a of the inner ring 1 and similarly extending in the axial direction are formed on the spherical inner peripheral surface of the outer ring 2 in the circumferential direction and the like.

The guide groove 1a of the inner ring 1 and the guide groove 2a of the outer ring 2
And one ball 3 is arranged in each pair of the guide grooves 1a and 2a.

The ball 3 is interposed between the guide groove 1a of the inner race 1 and the guide groove 2a of the outer race 2 to transmit torque therebetween, and is held at a predetermined position by a gauge 4.
The ball 3 is an outer ring 2 formed from a fiber-reinforced composite material.
By being assembled between the guide grooves 1a and 2a of the inner and outer races 1 and 2 utilizing the elasticity of the inner and outer races 1, an interference is provided so that the clearance between the inner and outer races 1 and 2 becomes negative.

The gauge 4 has a spherical inner peripheral surface that is in contact with the outer peripheral surface of the inner ring 1 and a spherical outer peripheral surface that is in contact with the inner peripheral surface of the outer ring 2. A pocket 6 for holding the ball 4 has a circular circumference. It is formed in the radial direction with the same orientation.

In the figure, reference numeral 7 denotes a flexible boot mounted between the opening of the outer race 2 and the steering shaft 5 to prevent foreign substances such as dust from entering the interior.

The constant velocity universal joint for steering of the present invention is:
As described above, the outer race 2 formed from the fiber-reinforced composite member
The ball 3 is assembled between the inner and outer rings 1 and 2 using the elasticity of
Since the clearance between the outer races 1 and 2 and the ball 3 is negative, there is no joint play, and power transmission is performed smoothly.

FIGS. 3 and 4 show another embodiment of the constant velocity universal joint for steering according to the present invention. In the guide groove 2a of the outer race 2, a metal (for example, quenched steel) or an oil-impregnated sintered material is used. Alternatively, by embedding a liner 8 formed of a wear-resistant material such as ceramics, the outer ring 2 has a function of withstanding abrasion due to friction with the ball 3. The embedding of the liner 8 is performed by molding with the outer ring 2 or by a strong adhesive.
If necessary, precision is obtained by machining. Further, since the liner 8 is partially embedded in the guide groove 2a of the outer race 1, the elasticity of the outer race 1 can be utilized in the same manner as in the embodiment of FIGS. It is possible to assemble the outer races 1 and 2 in a state where a margin is provided between the guide grooves 1a and 2a. Further, the liner 8 is divided and embedded in the guide groove 2a of the outer race 2, but may be embedded so as to be integrally connected as shown in FIG.

In the above embodiment, the case where the outer race 2 is formed of a fiber-reinforced composite material is described, but the present invention is not limited to this. For example, the inner ring 1 can also be formed from a fiber-reinforced composite material. In this case, since the elasticity of the inner ring 1 can also be used, the elasticity at the time of assembling is further increased to facilitate the assembling, and the ball 3 can be given a larger interference.
When the inner ring 1 is formed from a fiber-reinforced composite material as described above, if a liner formed from a wear-resistant material is embedded in the guide groove 1a of the inner ring 1, the inner ring 1 also wears due to friction with the ball 3. Function can be given. Further, when the gauge 4 is also formed from the fiber reinforced composite material, the sliding resistance between the inner and outer rings 1 and 2 is reduced, and more smooth power transmission is possible.

[0023]

As described above, in the present invention, at least the outer ring of the constituent members is formed from a fiber-reinforced composite member,
Utilizing the elasticity of this fiber-reinforced composite material, the ball is assembled between the inner and outer races with a tight allowance so that the clearance between the inner and outer races is negative. Power transmission is possible, and the weight of the conventional components is significantly reduced as compared with the case of using a metal material. Therefore, in a steering apparatus for an automobile, it is possible to simplify the shape of the steering shaft and reduce the weight.

Further, since the liner formed from the wear-resistant material is embedded in the guide grooves of the inner and outer rings formed from the fiber-reinforced composite material, the inner and outer rings formed from the fiber-reinforced composite material are in contact with the ball. Wear due to friction can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line BB (in FIG. 2) showing an embodiment of the constant velocity universal joint for steering of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a sectional view taken along line DD (in FIG. 4) showing another embodiment of the constant velocity universal joint for steering of the present invention.

FIG. 4 is a sectional view taken along line CC in FIG. 3;

FIG. 5 is a partial sectional view showing a modification of the liner.

[Explanation of symbols]

 Reference Signs List 1 inner ring 1a guide groove 2 outer ring 2a guide groove 3 ball 4 gauge 5 steering shaft 6 pocket 7 boot 8 liner

Claims (2)

(57) [Scope of request for utility model registration] An inner ring having a predetermined number of guide grooves formed on a spherical outer peripheral surface in an axial direction, and an inner ring formed on a spherical inner peripheral surface for connecting a steering shaft of an automobile to a steering gear. Outer races formed with the same number of guide grooves as in the above and also extending in the axial direction, a plurality of balls interposed between the guide grooves of the inner and outer rings to transmit torque, and the outer peripheral surface of the inner race and the outer race A gauge that holds the ball between the inner peripheral surface of the ball and the outer ring of the constituent members is formed from a fiber-reinforced composite material, and the ball is closed using the elasticity of the fiber-reinforced composite material. A constant velocity universal joint for steering, characterized by being provided. 2. The constant velocity universal joint for steering according to claim 1, wherein a liner formed of a wear-resistant material is embedded in the outer ring or the guide groove of the inner and outer rings.