JP2001355645A - Shaft joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shaft joint capable of securely reversing an auxiliary lip of a sealing member fixed on a cylindrical sleeve reversed during grease supply to a previous position by spline sliding of an inner shaft and the cylindrical sleeve. SOLUTION: The inner shaft is engaged with the cylindrical sleeve by spline slidably along an axial direction. The sealing member 5 sliding along a peripheral surface of the inner shaft is fixed on a tip part of the cylindrical sleeve, and a grease nipple for supplying grease to an inner part of the shaft joint is provided on the cylindrical sleeve. The sealing member 5 is constituted by a main lip 7 extending obliquely to an outer side of the shaft joint from a body part, and an auxiliary lip 8 provided on a back surface of the main lip 7 and extending obliquely to an inner side of the shaft joint. Plural reinforcing ribs 10 are formed on a surface of the auxiliary lip 8 on the shaft joint inner side along a circumference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft coupling used for an automobile or the like.

[0002]

2. Description of the Related Art Conventionally, a shaft coupling as shown in FIGS. 3 and 4, for example, has been known. That is, in this shaft coupling, the inner shaft 30 having the spline 31 formed on the outer peripheral surface and the annular sleeve 32 having the spline 33 formed on the inner peripheral surface are spline-fitted slidably in the axial direction. And a hermetic seal member 34 fixed to the distal end portion 32a. The sealing member 34 includes a main body 35,
The main lip 36 and the auxiliary lip 37 are formed. The main body 35 is provided at the distal end 32 of the annular sleeve 32.
a is formed of an outer annular portion 35a fixed to the outer peripheral surface, and a flange portion 35b extending radially inward from the outer annular portion 35a along the end surface of the distal end portion 32a of the annular sleeve 32. The flange 35b is formed so as to extend obliquely outward from the shaft coupling and to slide on the peripheral surface of the inner shaft 30. Further, the auxiliary lip 37 is formed on the back surface 36a of the main lip 36 and obliquely extends inside the shaft coupling. Extend to inner shaft 3
0 is in sliding contact with the peripheral surface. This sealing member 3
The main lip 36 prevents foreign matter such as muddy water from entering the inside from outside.
The grease sealed in the spline fitting portion between the sleeve and the annular sleeve 32 is prevented from leaking to the outside. Further, a grease nipple 38 is provided on the base side of the annular sleeve 32 to supply the grease. Although not shown, it is well known in the case of a shaft coupling that a universal joint is arranged on the opposite end side of the annular sleeve 32 and the inner shaft 30.

[0003]

In the above-mentioned shaft coupling, the inner lip 3 is attached to the auxiliary lip 37 of the sealing member 34.
To prevent leakage of grease sealed in the spline fitting portion of the annular sleeve 32 and the grease nipple 3.
Consideration must be given to compatibility with the workability of additional lubrication of grease from Step 8. That is, if the auxiliary lip 37 is too large for the inner shaft 30 in order to prevent leakage of the internal grease, air and old grease cannot come out from the inside when the grease is additionally greased. In addition, additional lubrication cannot be performed or workability deteriorates.
For this reason, usually, in consideration of the workability of additional lubrication, the squeeze of the auxiliary lip 37 is set to almost zero.

Therefore, when the grease is additionally supplied with the auxiliary lip 37 near zero, the auxiliary lip 37 is temporarily inverted with the passage of air or old grease, and its tip is located outside the shaft coupling. However, when the inner shaft 30 and the annular sleeve 32 are splined, they are reversed again and returned to the original position. However, it is difficult to adjust the auxiliary lip 37 to almost zero, and if the auxiliary lip is larger than a predetermined value, the original position of the auxiliary lip 37 is maintained even if the inverted auxiliary lip 37 is splined between the inner shaft 30 and the annular sleeve 32. May not be inverted again. When such a state occurs, there arises a problem that leakage of grease cannot be prevented.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and the reversal of the auxiliary lip of the hermetic seal member fixed to the annular sleeve at the time of grease supply is performed by spline sliding between the inner shaft and the annular sleeve. It is an object of the present invention to provide a shaft coupling that can be surely inverted to its original position again by movement.

[0006]

As means for solving the above-mentioned problems, an inner shaft and an annular sleeve are spline-fitted so as to be slidable in the axial direction, and slidably contact the distal end portion of the cylindrical sleeve with the peripheral surface of the inner shaft. In a shaft coupling, in which a sealing seal member is fixed and a grease nipple for supplying grease to the inside of the shaft coupling is provided in the annular sleeve, the sealing seal member is provided with a main lip extending obliquely from the main body portion to the outside of the shaft coupling, An auxiliary lip is provided on the back surface of the lip and extends obliquely inside the shaft coupling, and a plurality of circumferentially extending reinforcing ribs are formed on a surface of the auxiliary lip inside the shaft coupling.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a specific embodiment of the present invention will be described with reference to FIGS. In this shaft coupling, an inner shaft 1 having a spline 2 formed on the outer peripheral surface and an annular sleeve 3 having a spline 4 formed on the inner peripheral surface are spline-fitted in an axially slidable manner. 3a. The sealing member 5 includes a main body 6 and a main lip 7.
And the auxiliary lip 8. The main body 6 has an outer annular portion 6 a fixed to the outer peripheral surface of the distal end 3 a of the annular sleeve 3, and extends radially inward from the outer annular portion 6 a along the end surface of the distal end 3 a of the annular sleeve 3. The main lip 7 is formed so as to extend obliquely outward from the flange portion 6b to the outside of the shaft coupling, and to slide on the peripheral surface of the inner shaft 1 with a predetermined squeeze. Is formed on the back surface 7a of the main lip 7, extends obliquely inside the shaft coupling, and is slidably contacted with the peripheral surface of the inner shaft 1 in a state in which shrinkage is almost zero. The main lip 7 of the hermetic seal member 5 prevents foreign matter such as muddy water from entering the inside from the outside, and the outside of the grease sealed in the spline fitting portion between the inner shaft 1 and the annular sleeve 3 by the auxiliary lip 8. Is prevented from leaking. Further, a grease nipple 9 is provided on the base side of the annular sleeve 3 to supply the grease. Although not shown, it is well known in the art of a shaft coupling that a universal joint is arranged on the opposite end side of the annular sleeve 3 and the inner shaft 1.

On the surface 8a of the auxiliary lip 8 on the inner side of the shaft coupling, ribs 10 are formed at a plurality of positions on the circumference from the auxiliary lip tip 8b to the back surface 7a of the main lip 7. The auxiliary lip 8 is partially increased in rigidity by the rib 10. For this reason, only the weak portion of the auxiliary lip where the rib 10 is not formed is inverted by the grease lubrication pressure to relieve the rise of the internal pressure and allow the passage of air and old grease. The high rigidity portion is maintained in its original state without being inverted. Therefore, when the spline slides between the inner shaft 1 and the annular sleeve 3,
The portion of weak rigidity that has been dragged and inverted by the high rigidity portion is returned to the original position after being inverted again.

[0009]

According to the present invention, an inner shaft and an annular sleeve are spline-fitted so as to be slidable in the axial direction, and a sealing member which is in sliding contact with the inner shaft peripheral surface is fixed to the distal end of the cylindrical sleeve. In a shaft coupling having a sleeve provided with a grease nipple for supplying grease inside the shaft coupling, the seal seal member is provided with a main lip extending obliquely from the main body portion to the outside of the shaft coupling, and a shaft coupling provided on the back of the main lip. An auxiliary lip extending obliquely inward is formed, and a plurality of reinforcing ribs are formed circumferentially on a surface of the auxiliary lip on the inner side of the shaft coupling to partially increase the rigidity of the auxiliary lip. Therefore, even if only the weak portion of the auxiliary lip is reversed by the grease lubrication pressure, the high rigid portion is maintained at the original position, and the rigidity is maintained when the spline slides between the inner shaft and the annular sleeve. The part that has been dragged and inverted by the high part of the circle is surely inverted again to the original position. Therefore, leakage of grease can be reliably prevented, and additional grease can be reliably supplied.

[Brief description of the drawings]

FIG. 1 is a sectional view of a shaft coupling according to an embodiment of the present invention.

FIG. 2 is a sectional view of the sealing member shown in FIG. 1;

FIG. 3 is a sectional view of a conventional shaft coupling.

FIG. 4 is a sectional view of the sealing member shown in FIG. 3;

[Explanation of symbols]

 Reference Signs List 1 inner shaft 2 spline 3 annular sleeve 4 spline 5 sealing seal member 7 main lip 8 auxiliary lip 9 grease nipple 10 rib

Claims (1)

[Claims] An inner shaft and an annular sleeve are spline-fitted so as to be slidable in the axial direction, a hermetic seal member slidingly contacting a peripheral surface of the inner shaft is fixed to a tip end of the cylindrical sleeve, and a shaft coupling is fixed to the annular sleeve. In a shaft coupling provided with a grease nipple for lubricating grease therein, the sealing seal member is provided with a main lip extending obliquely from the main body portion to the outside of the shaft coupling, and a main lip provided obliquely on the back side of the main lip and inside the shaft coupling. And a plurality of reinforcing ribs formed circumferentially on a surface of the auxiliary lip inside the shaft coupling.