JPH11230185A - Tripod joint - Google Patents

Abstract

(57) [Problem] To provide a tripod type joint in which a roller can rotate smoothly in a roller groove. SOLUTION: A plurality of trunnion shafts 4 extending in a radial direction.
, A roller 5 having a substantially spherical outer peripheral surface rotatably mounted on a trunnion shaft 4 of the spider 1, and a roller groove 13 into which the roller 5 is inserted.
And a housing 11 having the same. The roller 5 is
A plurality of roller pieces 9 divided in the axial direction of the trunnion shaft 4
Formed from

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tripod joint applied to a drive shaft of a power transmission system of an automobile.

[0002]

2. Description of the Related Art As is well known, a tripod type joint for connecting an input shaft and an output shaft includes a spider having a plurality of trunnion shafts extending in a radial direction and a spider having a plurality of trunnion shafts. Freely mounted,
It has a roller having a substantially spherical outer peripheral surface and a housing having a roller groove in which the roller is inserted. One of the input shaft and the output shaft is connected to the spider, and the spider is connected to the housing. Or the other shaft is connected, so that even if an axis crossing angle occurs between the input shaft and the output shaft, the rotational torque is smoothly transmitted. Note that a similar configuration is described in Japanese Utility Model Laid-Open No. 1-8530.

[0003] The rollers of the tripod joint are:
When the axis crossing angle between the input shaft and the output shaft is zero, that is, the bending angle of the joint is zero, the input shaft connected to the spider and the output shaft connected to the housing are coaxial,
Since the trunnion shaft is perpendicular to the input shaft and the output shaft, the spherical outer peripheral surface of the roller contacts the roller groove of the housing and transmits torque without rotating. On the other hand, when the bending angle of the joint occurs, the trunnion shaft is inclined with respect to the output shaft, so that the roller comes into contact with the roller groove while being inclined.

The angle of inclination of the roller with respect to the roller groove changes from the maximum angle in the positive direction centering on zero to the maximum angle in the negative direction during one rotation of the joint. The change in the inclination angle is performed about the intersection of the axis of the input shaft and the axis of the trunnion axis.When the roller changes from the maximum tilt position in the positive direction to the maximum tilt position in the negative direction, Requires smooth rotation around the trunnion axis.

[0005]

However, the change in the inclination angle is performed about the intersection of the axis of the input shaft and the axis of the trunnion shaft, and the rollers are extended radially outward from the trunnion shaft. Because it is attached to
When this roller changes from the maximum tilt position in the positive direction to the maximum tilt position in the negative direction, one roller apparently moves in an arc around the intersection, and the point of contact with the roller groove of the roller The distance traveled by a roller depends on the position of the contact point in one roller.

That is, the distance by which the contact point of the roller contacting the roller groove on the tip end side of the trunnion shaft moves between the maximum inclination positions is determined by the contact point of the roller contacting the roller groove on the base end side of the trunnion shaft being the maximum inclination position. It will be longer than the distance traveled between.

For this reason, the roller has a difference in the rolling speed of the roller between the distal end side and the proximal end side of the trunnion shaft in one roller.
The roller cannot roll smoothly, and may slip between the roller groove.

If the roller slides between the roller groove and the roller groove, the roller and the roller groove will be worn out early, and an axial thrust force will be generated on the input shaft and the output shaft. There is a possibility that the output shaft will be vibrated.

The present invention has been devised in view of such a conventional situation, and an object of the present invention is to provide a tripod joint in which a roller can rotate smoothly in a roller groove.

[0010]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a spider having a plurality of trunnion shafts extending in a radial direction, and a substantially spherical shape sprung rotatably mounted on the trunnion shaft of the spider. A roller having an outer peripheral surface, a housing having a roller groove into which the roller is inserted,
Wherein the roller is formed of a plurality of roller pieces divided in the axial direction of the trunnion shaft.

According to a second aspect of the present invention, in the configuration of the first aspect of the present invention, the roller is such that the divided surfaces can be in contact with each other on the inner peripheral side of the roller piece and on the outer peripheral side. They are formed so as not to be in contact with each other.

According to a third aspect of the present invention, in the first aspect of the invention, the roller has a configuration in which a low friction portion is formed on a dividing surface.

According to a fourth aspect of the present invention, in the configuration of the first aspect, a bearing member is provided between the trunnion shaft and the roller in correspondence with each of the divided roller pieces. It is a configuration that is made.

Here, the number of roller pieces forming the roller is arbitrary, and it is desirable that the number is as large as possible. One of an input shaft and an output shaft is connected to the spider, and the other shaft is connected to the housing.

In such a configuration, the joint can transmit a rotational torque input to the input shaft to the output shaft, and the joint bends even when an axis crossing angle occurs between the input shaft and the output shaft. This enables smooth transmission.

When a bending angle is given to the joint, the trunnion shaft (for example, the input shaft side) is inclined with respect to the housing (for example, the output shaft side) in accordance with the bending angle. It comes into contact with the roller groove of the housing in an inclined state.

Here, the inclination angle of the roller with respect to the roller groove changes from the maximum angle in the positive direction to the maximum angle in the negative direction centering on zero during one rotation of the joint. The change in the inclination angle is performed about the intersection of the axis of the input shaft and the axis of the trunnion axis.When the roller changes from the maximum tilt position in the positive direction to the maximum tilt position in the negative direction, Is mounted on the trunnion shaft extending outward in the radial direction, so that it apparently moves in an arc around the intersection.

When the inclination angle of the roller with respect to the roller groove changes from the maximum angle in the positive direction to the maximum angle in the negative direction centering on zero, that is, the roller is inclined from the maximum inclination position in the positive direction to the maximum inclination position in the negative direction. When the contact point of the roller contacting the roller groove on the distal end side of the trunnion shaft moves between the maximum inclined positions, the distance between the contact point of the roller contacting the roller groove on the base end side of the trunnion shaft is the maximum inclined position. Roller is longer than the distance traveled by
In one roller, a difference occurs in the rolling speed of the roller between the distal end and the proximal end of the trunnion shaft. For this reason, the roller cannot smoothly roll, and there is a possibility that the roller may slip with the roller groove.
This can be advantageously solved.

That is, when there is a difference in the rolling speed of the roller between the tip end side and the base end side of the trunnion shaft, the roller is formed by a plurality of roller pieces divided in the axial direction of the trunnion shaft. Is absorbed by the plurality of roller pieces sliding relative to each other on the dividing surface, and the plurality of roller pieces can rotate at their own rolling speeds.

For this reason, the roller has a difference in rolling speed between the tip end side and the base end side of the trunnion shaft, but this speed difference is absorbed by the relative sliding of the plurality of roller pieces on the divided surface, and Since the roller pieces of the roller self-rotate at the respective rolling speeds, the roller does not eventually have a difference in the rolling speed depending on the contact position in the contact with the roller groove. As a result, smooth rolling of the roller is achieved, and sliding with the roller groove is advantageously prevented.

Therefore, a tripod-type joint is obtained in which the roller can smoothly rotate within the roller groove.

According to the second aspect of the present invention, since the divided surfaces of the rollers are formed so as not to be in contact with each other on the outer peripheral side of the rollers, lubrication of grease or the like is performed through a gap between the divided surfaces. The oil can be easily introduced into the division surface, and the division surface can be effectively lubricated.

According to the third aspect of the present invention, since the low friction portion is formed on the divided surface of the roller, relative sliding on the divided surface can be performed more smoothly.

According to the fourth aspect of the present invention, a bearing member is provided between the trunnion shaft and the roller in correspondence with each of the divided roller pieces. The rotation of the is smoother.

[0025]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view of a tripod type joint according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIGS. 3 to 5 are sectional views of rollers.

In FIG. 1, reference numeral 1 denotes a spider, and a spline hole 2 is formed in the spider 1, and an input shaft 3 is connected to the spider 1 by the spline hole 2. The spider 1 is formed with three trunnion shafts 4 projecting radially.

A roller 5 having a substantially spherical outer peripheral surface is rotatably mounted on each of the trunnion shafts 4. Specifically, the trunnion shaft 4 is inserted through a bearing member 7 into a through hole 6 formed in the roller 5. Further, a roller 5 is provided at the tip end side of the trunnion shaft 4.
And a retaining ring 8 for preventing the bearing member 7 from coming off.

The roller 5 is formed of a plurality of roller pieces 9 divided in the axial direction of the trunnion shaft 4, in this embodiment, two roller pieces 9. (See FIG. 3). The number of divisions of the roller 5, that is, the number of the roller pieces 9 forming the roller 5, is arbitrary, and as shown in FIG.
, Or from more roller pieces.

Further, as shown in FIG. 5, the rollers 5 are formed so that the entire surfaces of the divided surfaces are not in contact with each other, but are in contact with each other on the inner peripheral side of the roller pieces 9 and are not in contact with each other on the outer peripheral side. It is possible. As a result, a gap is formed on the outer peripheral side of the roller 5, so that lubricating oil such as grease can be easily introduced into the divided surface from the gap,
Lubrication of the divided surface can be effectively performed.

The roller 5 has a low friction portion 10 formed on a divided surface. The low friction portion 10 is formed by applying a phosphate coating treatment, a molybdenum coating treatment, a Teflon (registered trademark) coating treatment, or the like to the divided surface of the roller 5, that is, the side surface of the roller piece 9. Further, the low friction portion 10
Can be formed by sandwiching a low friction material made of Teflon (registered trademark) or the like between the divided surfaces of the rollers 5, that is, between the roller pieces 9.

Reference numeral 11 denotes a hollow housing having one end sealed, and an output shaft 12 is integrally formed at the sealed end of the housing 11. A roller groove 13 into which the roller 5 is inserted is formed in the hollow interior of the housing 11, and the roller groove 13 is formed parallel to the axis X2 of the output shaft 12. A dust cover 14 is attached to the outer periphery of the output shaft 12.

The open end of the housing 11 is sealed by a boot (not shown),
The inside of the hollow is appropriately filled with lubricating oil such as grease.

In such a configuration, the joint can transmit the rotational torque input to the input shaft 3 to the output shaft 12, and even when an axis crossing angle occurs between the input shaft 3 and the output shaft 12, Bending of the joint enables smooth transmission.

At this time, when the axis crossing angle between the input shaft 3 and the output shaft 12 is zero, that is, when the bending angle of the joint is zero, the roller 5 is connected to the shaft of the input shaft 3 connected to the spider 1. The core X1 and the axis X2 of the output shaft 12 integrally connected to the housing 11 are in a state of being united, and the axis Y of the trunnion shaft 4 is orthogonal to the axis X1 and the axis X2. In this state, the spherical outer peripheral surface of the roller 5 comes into contact with the roller groove 13 and transmits rotational torque without rotating. On the other hand, if the bending angle of the joint occurs, the trunnion shaft 4 is inclined with respect to the housing 11, so that the roller 5 comes into contact with the roller groove 13 of the housing 11 while being inclined. .

Here, the inclination angle of the roller 5 with respect to the roller groove 13 changes from the maximum angle in the positive direction to the maximum angle in the negative direction around zero during one rotation of the joint. The change of the inclination angle is performed around the intersection O of the axis X1 of the input shaft 3 and the axis Y of the trunnion shaft 4, and the roller 5 is moved from the maximum inclination position in the positive direction to the maximum inclination position in the negative direction. When the roller 5 changes, since the roller 5 is attached to the trunnion shaft 4 extending outward in the radial direction, the roller 5 apparently moves in an arc around the intersection O.

Therefore, when the inclination angle of the roller 5 with respect to the roller groove 13 changes from the maximum angle in the positive direction to the maximum angle in the negative direction around zero, that is, the roller 5
Is changed from the maximum tilt position in the positive direction to the maximum tilt position in the negative direction, the distance that the contact point of the roller 5 contacting the roller groove 13 on the tip end side of the trunnion shaft 4 moves between the maximum tilt positions is Since the contact point of the roller 5 in contact with the roller groove 13 on the base end side is longer than the distance moved between the maximum inclined positions, the roller 5 is connected to the tip end side of the trunnion shaft 4 in one roller 5. A difference occurs in the rolling speed of the roller 5 on the base end side. As a result, the roller 5 cannot roll smoothly, and may slip between the roller groove 13. This can be advantageously solved in the present invention.

That is, when there is a difference in the rolling speed of the roller 5 between the front end side and the base end side of the trunnion shaft 4, the roller 5 is formed by a plurality of roller pieces 9 divided in the axial direction of the trunnion shaft 4. Therefore, the difference between the rolling speeds generated by the rollers 5 is absorbed by the plurality of roller pieces 9 sliding relative to each other on the divided surface, and the plurality of roller pieces 9 rotate at their respective rolling speeds. It is possible to do.

For this reason, the roller 5 has a difference in rolling speed between the tip end side and the base end side of the trunnion shaft 4, but this speed difference is absorbed by the relative sliding of the plurality of roller pieces 9 on the divided surface. Since the plurality of roller pieces 9 rotate at their respective rolling speeds, the roller 5
Does not cause a difference in rolling speed depending on the contact position in contact with the roller groove 13. As a result, the roller 5 is smoothly rolled, and the sliding between the roller 5 and the roller groove 13 is advantageously prevented.

Therefore, the roller 5 is provided in the roller groove 13
A tripod joint that can rotate smoothly within the joint can be obtained.

Further, by forming the divided surfaces of the rollers 5 so as not to be in contact with each other on the outer peripheral side of the roller piece 9, lubricating oil such as grease can be easily introduced into the divided surfaces through the gap between the divided surfaces. Therefore, lubrication of the divided surface can be effectively performed.

Further, a low friction portion 1 is provided on the divided surface of the roller 5.
By forming 0, relative sliding on the division surface can be performed more smoothly.

FIG. 6 is a view showing another embodiment of the present invention. This embodiment is different from the above-described embodiment in that a divided roller piece 9 is provided between the trunnion shaft 4 and the roller 5. Is that a bearing member 7A is provided for each of the above.

That is, in this embodiment, the roller 5 is formed of two roller pieces 9, and a bearing member 7 A is provided for each of the roller pieces 9. A washer 15 is interposed between the bearing members 7A.

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.

In this embodiment, when the joint bends to cause a difference in the rolling speed of the roller 5 between the distal end side and the base end side of the trunnion shaft 4, the rolling speed of the roller 5 is reduced. The difference is absorbed by the plurality of roller pieces 9 sliding relative to each other on the divided surface, and the plurality of roller pieces 9 can rotate at their respective rolling speeds. In this case, the trunnion shaft 4
Between the roller 5 and the roller 5, the bearing members 7A are provided corresponding to each of the divided roller pieces 9, so that the rotation of the roller pieces 9 becomes smoother.

Therefore, the roller 5 is smoothly rolled, and the sliding between the roller 5 and the roller groove 13 is advantageously prevented.

Therefore, also in this embodiment,
As in the above-described embodiment, a tripod joint in which the roller 5 can smoothly rotate within the roller groove 13 is obtained.

In addition, since the bearing members 7A are provided corresponding to the respective roller pieces 9, the roller pieces 9
The rotation of the is smoother.

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, in the above-described embodiment, the so-called sliding tripod type joint in which the roller groove 13 is formed in parallel with the output shaft 12 and is extendable and contractible has been described. Is also possible.

[0051]

As described above in detail, according to the present invention, a tripod joint in which a roller can smoothly rotate within a roller groove can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a tripod joint according to an embodiment of the present invention.

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

FIG. 3 is a sectional view of the roller shown in FIG. 1;

FIG. 4 is a sectional view showing another embodiment of the roller.

FIG. 5 is a sectional view showing another embodiment of the roller.

FIG. 6 is a view similar to FIG. 1, showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spider 3 Input shaft 4 Trunnion shaft 5 Roller 9 Roller piece 12 Output shaft

Claims (4)

[Claims] 1. A spider having a plurality of trunnion shafts extending in a radial direction, a roller having a substantially spherical outer peripheral surface rotatably mounted on the trunnion shaft of the spider, and a roller fitted with the roller. And a housing having a groove, wherein the roller is formed from a plurality of roller pieces divided in the axial direction of the trunnion shaft. 2. The roller according to claim 1, wherein the divided surfaces are formed so as to be able to contact each other on the inner peripheral side of the roller piece and not to be in contact with each other on the outer peripheral side. 3. The tripod joint according to 1. 3. The tripod-type joint according to claim 1, wherein the roller has a low friction portion formed on a dividing surface. 4. Between the trunnion shaft and the roller,
The tripod joint according to claim 1, wherein a bearing member is provided corresponding to each of the divided roller pieces.