JPH11247879A - Universal coupling free to slide in axial direction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a universal coupling capable of bending even when excessive force is input in the axial direction and free to slide in the axial direction. SOLUTION: An outside member 4 is installed on an input shaft 1 on a universal coupling 3 to link the input shaft 1 and an output shaft 2 and free to slide in the axial direction. An inside member 11 arranged in the inside of the outside member 4 and installed on the output shaft 2 is provided. Ball grooves 10, 14 in the axial direction are respectively provided on the outside member 4 and the inside member 11. Balls 15 arranged in ball grooves 10, 14 and to link the outside member 4 and the inside member 11 are provided. A contact body 21 as a first contact part is provided on the outside member 4 in the inside of the outside member 4. A second contact part 23 free to make contact with the contact body 21 as the first contact part is provided on the output shaft 2 on which the inside member 11 is installed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axially slidable universal joint which can be used for a propulsion shaft or a steering column of an automobile.

[0002]

2. Description of the Related Art A universal joint of this type is disclosed in, for example,
As shown in FIGS. 7 to 10 of Japanese Patent No. 10957, an outer member attached to an input shaft, an inner member disposed inside the outer member and attached to an output shaft, and an outer member or an inner member attached to the output shaft. Either or both of them include a guide groove formed in the axial direction, and a spherical member disposed in the guide groove and communicating between the outer member and the inner member.

The universal joint is slidable in the axial direction by rolling the spherical member in the guide groove.
It is bendable. That is, the sliding and bending of the universal joint are performed within the range of the guide groove.

Japanese Utility Model Laid-Open Publication No. 3-112427 discloses that when an axial impact load is applied between an input shaft and an output shaft connected to the universal joint, the universal joint slides in the axial direction. It has been proposed to absorb the impact load by bending and bending to substantially reduce the axial dimension between the input and output shafts.

[0005]

However, when the universal joint is slid and bent to absorb an impact load, an excessive force is applied to the universal joint, and an excessive force is applied to the universal joint. Axial sliding beyond the range may be required.

In this case, if the universal joint is slid in the axial direction beyond the allowable range, the spherical member may ride on the end of the guide groove and may not be bent. This means that if the universal joint cannot be bent, the bending of the universal joint cannot substantially reduce the size between the input member and the output member. The expected performance cannot be obtained.

The present invention has been devised in view of the above conventional circumstances, and provides an axially slidable universal joint that can bend even when an excessive force is input in the axial direction. The purpose is to:

[0008]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to an axially slidable universal joint for connecting an input shaft and an output shaft, wherein the universal joint is slidable in either the input shaft or the output shaft. An outer member attached to one of the shafts; an inner member disposed inside the outer member and attached to the other one of the input shaft and the output shaft; and one or both of the outer member and the inner member A guide groove formed in the axial direction, a spherical member disposed in the guide groove and communicating between the outer member and the inner member, and inside the outer member, the outer member or the outer member is A first contact portion formed on a shaft to be attached; and a second contact portion formed on the inner member or a shaft to which the inner member is attached and capable of contacting the first contact portion. It has a configuration.

According to a second aspect of the present invention, in the configuration of the first aspect, at least one of the first contact portion and the second contact portion has a hemispherical outer peripheral surface. The first contact portion and the second contact portion can be point-contacted by the hemispherical outer peripheral surface.

According to a third aspect of the present invention, in the configuration of the first aspect, the first contact portion is a contact member provided on a bottom portion of the outer member.

According to a fourth aspect of the present invention, in the first aspect of the invention, the first contact portion is formed on a nut attached to a tip of a shaft to which the outer member is attached. It is.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the first contact portion is formed at a tip of a shaft to which an outer member is attached.

According to a sixth aspect of the present invention, in the configuration of the first aspect, the outer member is formed integrally with one of an input shaft and an output shaft to which the outer member is attached. Configuration.

The universal joint slidable in the axial direction is as follows.
Various types of axially slidable universal joints, such as a double offset type universal joint in which the spherical member is a ball and a sliding tripod type universal joint in which the spherical member is a roller, are included.

In this configuration, the universal joint has an input shaft connected to a driving device and an output shaft connected to a driven device, and is used for power transmission.

That is, the rotational driving force input from the driving device to the input shaft is transmitted to the output shaft via the universal joint.
The power is transmitted to a driven device connected to the output shaft.

At this time, the universal joint bends when an intersection angle occurs between the input shaft and the output shaft, and the spherical member moves on a bisector of the intersection angle between the input shaft and the output shaft. Then, it controls power transmission while maintaining constant speed between the input shaft and the output shaft. Further, when an axial force acts on the input shaft and the output shaft, the spherical member moves in the guide groove in the axial direction, so that the spherical member moves within a predetermined range not exceeding the axial length of the guide groove. , It is possible to expand and contract in the axial direction of the input shaft and the output shaft.

When an excessive force in the axial direction is input to the universal joint, the first contact portion and the second contact portion contact each other.

At this time, the spherical member is in the guide groove, and can roll in the guide groove. For this reason, the universal joint is bendable in a state where the first contact portion and the second contact portion are in contact with each other.

In the state where the first contact portion and the second contact portion are in contact with each other, the bending resistance of the universal joint is greater than when the first and second contact portions are not in contact with each other. The second joint comes into contact with the second contact portion when an excessive force is input to the universal joint than usual, and the universal joint can be easily bent by this force.

Accordingly, a universal joint slidable in the axial direction, which can bend even when an excessive force is input in the axial direction, is obtained.

According to the second aspect of the present invention, since the first contact portion and the second contact portion make point contact, the bending operation of the universal joint becomes smooth.

According to the third aspect of the present invention, since the first contact portion is constituted by the contact member provided on the bottom of the outer member, the material of the contact member is arbitrarily selected. It is possible.

According to the fourth aspect of the present invention, since the first contact portion is formed on the nut attached to the tip of the shaft to which the outer member is attached, it is possible to prevent an increase in the number of parts. Can be.

According to the fifth aspect of the present invention, since the first contact portion is formed at the tip of the shaft to which the outer member is attached, it is possible to prevent an increase in the number of parts.

According to the sixth aspect of the present invention, the outer member is formed integrally with one of the input shaft and the output shaft to which the outer member is attached.
An increase in the number of parts can be prevented.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as embodiments applied to a double offset type universal joint.

FIG. 1 is a cross-sectional view of a universal joint slidable in an axial direction, showing an embodiment of the present invention. FIG. 2 is a universal joint in which a first contact portion and a second contact portion abut. It is sectional drawing explaining the state which bent.

In the figure, 1 is an input shaft, 2 is an output shaft, and 3 is a universal joint connecting the input shaft 1 and the output shaft 2.

Reference numeral 4 denotes an outer member of the universal joint 3. The outer member 4 is attached to either the input shaft 1 or the output shaft 2, in this embodiment, the input shaft 1. That is, the outer member 4 is formed in a substantially cup shape, and the bottom 5 is attached to the input member 1 via the spline joint 6. Specifically, a shaft spline 6a is formed at the end 1A of the input shaft 1, and a hole spline 6a is formed at the bottom 5 of the outer member 4, and are press-fitted and fixed to each other. A screw 7 is formed at the tip of the input shaft 1, and a nut 9 is screwed and fixed to the screw 7 via a washer 8.

Reference numeral 10 denotes a ball groove (guide groove) formed on the inner peripheral side of the outer member 4. The plurality of ball grooves 10 are formed in the outer member 4 in the axial direction, and are arranged at equal intervals in the circumferential direction. The ball groove 10 is formed over a predetermined length from the opening end side of the outer member 4 to the bottom 5 side. In the ball groove 10, a ball (spherical member) to be described later is arranged.

An inner member 11 is disposed inside the outer member 4. The inner member 11 is either the input shaft 1 or the output shaft 2, and in this embodiment, the output shaft 2
Mounted on That is, the inner member 11 is formed in a substantially cylindrical shape having a spherical surface on the outer peripheral side, and the inner peripheral side is connected to the end (the left end in FIG. 1) 2A of the output shaft 2 via the spline joint 12. Installed. Specifically, a shaft spline 12a is formed on the end 2A of the output shaft 2, and a hole spline 12b is formed on the inner member 11, and are press-fitted and fixed to each other. The inner member 1
1 is prevented from being pulled out by a snap ring 13.

Reference numeral 14 denotes a ball groove (guide groove) formed on the outer peripheral side of the inner member 11. The plurality of ball grooves 14 are formed in the axial direction of the inner member 11 and arranged at equal intervals in the circumferential direction. The number of the ball grooves 14 is the ball groove 1
The same number as the number of 0 is formed so as to form a pair.
The ball groove 14 is formed over the entire length of the inner member 14. In the ball groove 14, similarly to the ball groove 10 of the outer member 4, a ball (spherical member) described later is arranged.

Reference numeral 15 denotes a plurality of balls (spherical members) arranged in the ball grooves 10, 14. The plurality of balls 15 are arranged in paired ball grooves 10 and 14 while being aligned and held in the same plane by a cage 16, and connect the outer member 4 and the inner member 11.

Reference numeral 21 denotes a contact body as a first contact portion.
The contact member 21 is provided inside the outer member 4 so that the outer member 4 or the input shaft 1 to which the outer member 4 is attached.
In this embodiment, it is attached to the bottom 5 of the outer member 4.

The contact body 21 is formed in a dish shape as a whole from a metal material or a hard synthetic resin material, and has a hemispherical outer peripheral surface 22 formed thereon. The surface 22 is mounted so as to project toward the inside of the outer member 4.

Reference numeral 23 denotes a second contact portion. The second contact portion 23 can be formed on the inner member 11 or the output shaft 2 to which the inner member 11 is attached. In this embodiment, the second abutment portion 23 is formed at the tip of the output member 2.

The second contact portion 23 has a hemispherical outer peripheral surface 2.
4, and the hemispherical outer peripheral surface 24 protrudes toward the contact body 21 attached to the outer member 4.

Reference numeral 25 denotes a retaining ring attached to the open end of the outer member 4. The retaining ring 25 prevents the ball 15 held by the cage 16 from coming out of the ball groove 10.

Reference numeral 30 denotes a sealing member for controlling the sealing of the universal joint 3. The sealing member 30 includes a substantially cylindrical boot adapter 31 made of a metal material, and a flexible boot 32 made of a rubber material or a synthetic resin material, one end of which is attached to the boot adapter 31. 31 is attached to the outer member 4 of the universal joint 3, and the other end of the boot 32 is attached to the outer periphery of the output shaft 2 by an attachment band 33.

Reference numeral 34 denotes a tube for controlling power transmission. The tube 34 is made of a metal material, a fiber-reinforced synthetic resin material, or the like, and has an end portion of the output shaft 22 (the right end portion 2B in FIG. 1).
Mounted on More specifically, the outer periphery of the right end 2B of the output shaft 2 is reduced in diameter by a predetermined thickness over a substantially length of the tube 34 over a predetermined length. It is press-fitted into the outer peripheral portion and is attached by welding or bonding.

In such a configuration, the universal joint 3 is
The input shaft 1 is connected to a driving device (not shown), and the output shaft 2 is connected to a driven device (not shown) via a tube 4 and used for power transmission.

That is, the rotational driving force input to the input shaft 1 from the driving device (not shown) is applied to the output shaft 2 via the universal joint 3.
And transmitted to the tube 34 and transmitted to a driven device (not shown) connected to the tube 34.

At this time, the universal joint 3 bends when an intersection angle occurs between the input shaft 1 and the output shaft 2, and the universal joint 3 is connected to the output shaft 2 while the ball 15 is held in the cage 16. It moves on a bisector of the intersection angle with the shaft 2 and controls power transmission while maintaining constant speed between the input shaft 1 and the output shaft 2. When an axial force acts on the input shaft 1 and the output shaft 2, the ball 15 moves in the ball groove 10 of the outer member 4 in the axial direction, so that the axial length of the ball groove 10 is increased. Within a predetermined range that does not exceed the height, it can expand and contract in the axial direction of the input shaft 1 and the output shaft 2.

When an excessive force in the axial direction is applied to the universal joint 3, the contact member 21 as the first contact portion and the second contact portion 23 come into contact with each other.

At this time, the ball 15 is in the pair of ball grooves 10 and 14, and can roll in the ball grooves 10 and 14. For this reason, the universal joint 3 is bendable in a state where the contact body 21 and the second contact portion 23 are in contact with each other (see FIG. 2).

The contact body 21 as the first contact portion and the second
In the state where the contact portions 23 are in contact with each other, the bending resistance of the universal joint 3 is larger than when they do not contact, but the contact body 21 and the second contact portions 23 are in contact with each other. This is the case where an excessive force is input to the universal joint 3 than usual, so that the universal joint 3 can be easily bent by this force.

Accordingly, the universal joint 3 slidable in the axial direction, which can bend even when an excessive force is input in the axial direction, is obtained.

The contact member 21 and the second contact portion 23
Are formed with a hemispherical outer peripheral surface 22 and an outer peripheral surface 24, and the contact body 21 and the second contact portion 23 make point contact with each other, so that the bending operation of the universal joint 3 becomes smooth.

Further, since the contact body 21 is provided separately on the bottom 5 of the outer member 4, the material of the contact body 21 can be arbitrarily selected.

FIG. 3 is a view showing another embodiment of the present invention. This embodiment is different from the first embodiment in that the first contact portion is attached to the tip of the input shaft 1 to which the outer member 4 is attached. This is a point formed on the nut 9.

That is, the nut 9 is formed in a bag shape, the first contact portion 21 is formed on the tip end side, and the hemispherical outer peripheral surface 2 is formed.
2 are formed.

Since other configurations are the same as those of the above-described embodiment, the same components are denoted by the same reference numerals, and redundant description will be omitted.

According to this configuration, when an excessive axial force is applied to the universal joint 3, the first contact portion 21 and the second contact portion 23 on the tip side of the nut 9 are mutually connected. Abut

At this time, the ball 15 is in the pair of ball grooves 10 and 14, and can roll in the ball grooves 10 and 14. For this reason, the universal joint 3 becomes bendable in a state where the first contact portion 21 and the second contact portion 23 are in contact with each other, and the same operation and effect as those of the above embodiment can be obtained.

Therefore, the universal joint 3 slidable in the axial direction, which can bend even when an excessive force is input in the axial direction, is obtained.

The first contact portion 2 is attached to the tip of the nut 9.
Since 1 is formed, an increase in the number of parts can be prevented.

FIG. 4 is a drawing showing another embodiment of the present invention. This embodiment is different from the first embodiment in that the first contact portion is formed at the tip of the input shaft 1 to which the outer member 4 is attached. That is the point.

That is, the tip of the input shaft 1 is extended toward the inside of the outer member 4, and the first end of the input shaft 1 is
A contact portion 21 is formed, and a hemispherical outer peripheral surface 22 is formed.

Since other configurations are the same as those of the above-described embodiment, the same components are denoted by the same reference numerals, and redundant description will be omitted.

According to such a configuration, when an excessive force in the axial direction is input to the universal joint 3, the first contact portion 21 and the second contact portion 23 on the distal end side of the input shaft 1 are connected to each other. Abut.

At this time, the ball 15 is in the pair of ball grooves 10 and 14, and can roll in the ball grooves 10 and 14. For this reason, the universal joint 3 becomes bendable in a state where the first contact portion 21 and the second contact portion 23 are in contact with each other, and the same operation and effect as those of the above embodiment can be obtained.

Accordingly, the universal joint 3 slidable in the axial direction, which can bend even when an excessive force is input in the axial direction, is obtained.

A first contact portion 2 is provided at the tip of the input shaft 1.
Since 1 is formed, an increase in the number of parts can be prevented.

FIG. 5 is a drawing showing another embodiment of the present invention.
However, the point is that the outer member 4 is formed integrally with the input shaft 1 to which the outer member 4 is attached.

That is, the outer member 4 is formed integrally with the input member 1, and washers and nuts are eliminated. Further, as in the embodiment shown in FIG. 1, a contact body 21 as the first contact portion is attached to the bottom of the outer member 4.

The other components are the same as those of the above-described embodiment. Therefore, the same components are denoted by the same reference numerals, and redundant description will be omitted.

According to this structure, when an excessive force in the axial direction is applied to the universal joint 3, the contact member (first contact portion) 21 disposed on the bottom of the outer member 4 and the second contact member 21 are disposed. The contact portions 23 come into contact with each other.

At this time, the ball 15 is in the pair of ball grooves 10 and 14, and can roll in the ball grooves 10 and 14. Therefore, the universal joint 3 can be bent in a state where the contact body 21 and the second contact portion 23 are in contact with each other, and the same operation and effect as those of the above embodiment can be obtained.

Therefore, the universal joint 3 slidable in the axial direction, which can bend even when an excessive force is input in the axial direction, is obtained.

Further, since the input shaft 1 and the outer member 4 are integrally formed, an increase in the number of parts can be prevented.

Although the embodiment has been described with reference to the drawings, the specific configuration is not limited to this embodiment, and can be changed without departing from the spirit of the invention.
For example, it is arbitrarily possible to apply a surface treatment to the first contact portion 21 and the second contact portion 23. Further, the second contact portion 23 may be formed on an inner member.

[0073]

As described above, according to the present invention, an axially slidable universal joint that can bend even when an excessively large force is input in the axial direction is obtained. .

[Brief description of the drawings]

FIG. 1 is a sectional view of a universal joint slidable in an axial direction according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a state in which a first contact portion and a second contact portion are in contact with each other and a universal joint is bent.

FIG. 3 is a sectional view of a universal joint showing another embodiment of the present invention.

FIG. 4 is a cross-sectional view of a universal joint showing another embodiment of the present invention.

FIG. 5 is a sectional view of a universal joint according to another embodiment of the present invention.

[Description of Signs] 1 Input shaft 2 Output shaft 3 Universal joint 4 Outer member 10 Ball groove (guide groove) 11 Inner member 14 Ball groove (guide groove) 15 Ball (spherical member) 21 Contact body (first contact portion) ) 23 Second contact part

Claims (6)

[Claims] An outer member attached to one of the input shaft and the output shaft, wherein the outer member is attached to one of the input shaft and the output shaft. And an inner member attached to the other shaft of the input shaft or the output shaft; a guide groove formed in one or both of the outer member and the inner member in an axial direction; A spherical member disposed in the groove and communicating between the outer member and the inner member, and a first contact portion formed on the shaft to which the outer member or the outer member is attached inside the outer member, A second contact portion formed on the inner member or a shaft to which the inner member is attached, the second contact portion being capable of contacting the first contact portion. Fittings. 2. A hemispherical outer peripheral surface is formed on at least one of the first contact portion and the second contact portion, and the first contact portion and the second contact portion are formed by the hemispherical outer peripheral surface. 2. The universal joint slidable in the axial direction according to claim 1, wherein the contact portion is capable of performing point contact. 3. The universal joint slidable in the axial direction according to claim 1, wherein the first contact portion is a contact member provided at a bottom of an outer member. 4. The universal joint slidable in the axial direction according to claim 1, wherein the first contact portion is formed on a nut attached to a tip of a shaft to which the outer member is attached. . 5. The universal joint slidable in the axial direction according to claim 1, wherein the first contact portion is formed at a tip of a shaft to which an outer member is attached. 6. The sliding member according to claim 1, wherein the outer member is formed integrally with one of an input shaft and an output shaft to which the outer member is attached. Possible universal joint.