JP3309042B2 - Universal joint boots - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boot of a universal joint for preventing oil from splashing from the inside of the universal joint and entry and entrapment of foreign matter from the outside.

[0002]

2. Description of the Related Art Conventionally, bellows type boots (bellows boots) have been used as boots for such universal joints. In such a bellows boot, the small-diameter end is fixed around one joint-side base end, and the large-diameter end is fixed around the opposing front end of the other joint.

[0003]

However, the conventional bellows boots can be bent with a change in the angle of the universal joint, but have a drawback that they may be broken by fatigue and have a short life. Further, since the mold has a complicated shape, there is a disadvantage that the cost for manufacturing the mold is high.

Accordingly, it is an object of the present invention to provide a universal joint boot which does not bend even if the angle of the universal joint changes, has no bending fatigue, and can be manufactured at low cost.

[0005]

In order to achieve this object, a boot of a universal joint according to the present invention has a self-supporting bowl made of a pair of elastomers whose small diameter portions are engaged with a driving joint and a driven joint, respectively. The boot half has a front half that faces each other and is slidable with each other so that the overlap does not come off even when the drive side and the driven side of the joint are at the maximum angle. An annular sealing means is provided on the inner surface of the tip portion of the coming boot half, a thin folded sleeve portion is provided on the outer surface extending forward than the annular sealing means on the inner surface side, and the outer boot is provided on the outer surface side of the annular sealing means. A retaining ring for preventing the half from deforming outward in the radial direction is arranged, and the folded back sleeve portion is closely attached to the outer surface of the retaining ring. Characterized by fixing the holding Schilling by.

[0006]

BACKGROUND OF THE INVENTION In the embodiment of the present invention, if a bead is provided at the end of the folded sleeve, the sealing performance with respect to the retaining ring in the folded sleeve is improved.
Deterioration of the retaining ring can be prevented. Further, when at least one annular reinforcing rib is provided on the inner surface of the boot half body, the durability of the boot is further improved. Furthermore,
Preferably, a flare is provided at the front edge of the inner boot half in a radially outward direction so as to make sliding contact with the inner surface of the outer boot half.

According to the present invention, in response to a change in the angle of the universal joint, the boot halves move together with the corresponding joints on which the respective proximal ends are engaged, and the boot halves slide with each other. The boot half itself does not bend.

[0008]

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

FIG. 1 shows a boot 1 of a universal joint according to the present invention.
The embodiment of the present invention is shown diagrammatically, and the universal joint covered by the boot 1 can be any type of universal joint, for example a universal joint with a cross-shaft or a constant velocity joint of any type. Is not shown and only the outline is shown.

The universal joint boot 1 includes a pair of bowl-shaped boot halves 2 and 3 for fixing the small diameter portions 2a and 3a to the driving end joint base end and the driven end joint base end, respectively. Opposing forward portions of the halves overlap and are slidable relative to one another. For this reason, these boot halves 2 and 3 are formed so as to be self-supporting due to the elastomer. Inside boot half 3
It is preferable to provide a flare 3b which is bent outward in the radial direction and slidably contacts the inner surface of the outer boot half at the front edge of the outer boot half. FIG.
1A shows a state in which the axes of the shafts on the driving side and the driven side are aligned with each other, and FIG. 1B shows a state in which the axes of the shafts on the driving side and the driven side are at an angle to each other. .

The boot halves 2 and 3 are dimensioned so that the overlap does not come off even when the drive side and the driven side of the joint are at the maximum angle, and an annular sealing means 4 is provided on the inner surface of the tip portion of the boot half 2 that comes above. The outer surface is provided with a thin folded sleeve portion 5 extending forward from the inner annular sealing means 4. The annular sealing means 4 may be constituted by a relatively long annular lip seal 4a at the forefront end and an annular rib seal 4b behind the seal.

As clearly shown in FIG. 2, the annular sealing means 4
A retaining ring 6 for preventing the outer boot half 2 from deforming outward in the radial direction is disposed on the outer surface side of the
Is fixed by folding back the sleeve 5 for folding. The retaining ring 6 is preferably made of metal, and in the illustrated embodiment is a ring having a flat rectangular cross section, but may be a wire ring.

Further, a bead 5 is provided at the tip of the folded sleeve 5.
a is provided. The bead 5a seals the holding ring 6 in which the sleeve 5 is closed, thereby preventing the holding ring 6 from deteriorating. Although not shown in the illustrated embodiment, the durability is improved by providing at least one annular reinforcing rib on the inner surface of the boot half body.

FIG. 3 shows another embodiment of the boot of the universal joint according to the present invention. In this embodiment, the small-diameter portion of the outer boot half 2A is placed closer to the distal end than the base end of the corresponding joint. This is an embodiment of the present invention. In this embodiment, the boot halves slide relative to each other and the outer boot halves also slide along the outer surface of the joint where the small diameter portion engages.

[0015]

According to the universal joint boot of the present invention, the boot halves move together with the joint on the side where the boot halves are fixed, and the boot halves partially overlapping each other slide with each other. Since the relative angles of the driving-side joint and the driven-side joint can be changed without bending the boot half itself, a long life can be obtained without bending fatigue.

Further, the boot of the universal joint of the present invention is constituted by a pair of bowl-shaped boot halves, and is not a complicated bent shape as in a conventional bellows boot.
The mold for manufacturing can be simplified, and can be manufactured at a considerably lower cost than before. In addition, since the holding ring can be fixed simply by folding back the folding sleeve 5, an effect that the workability of assembling is improved can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a preferred embodiment of a universal joint according to the present invention, wherein (a) shows a state in which axes of a driving-side joint and a driven-side joint are aligned with each other, and (b) forms an angle. Indicates the status.

FIG. 2 is an explanatory view showing a step of attaching a retaining ring to an end of a boot half that overlaps the outside of the embodiment of FIG. 1;

FIGS. 3A and 3B are explanatory views of another preferred embodiment of the universal joint according to the present invention, wherein FIG. 3A shows a state in which axes of a driving-side joint and a driven-side joint are aligned with each other, and FIG. Shows the done state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Universal boot 2a, 3a Small diameter part 2, 3 Boot half 4 Annular sealing means 4a Annular lip-shaped seal 4b Annular rib-shaped seal 5 Folding sleeve 5a Ball 6 Holding ring

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16D 3/84

Claims (2)

(57) [Claims] 1. A boot for a universal joint, comprising a pair of self-supporting bowl-shaped boot halves made of an elastomer in which a small-diameter portion is engaged with a drive-side joint and a driven-side joint, respectively. The parts are overlapped with each other and slidable with each other, so that the overlap does not come off even when the driving side and the driven side of the joint form the maximum angle, and an annular sealing means is provided on the inner surface of the tip portion of the boot half that comes above. The outer surface is provided with a thin folded sleeve portion extending forward from the inner side annular sealing means, and the outer side of the annular sealing means is held to prevent the outer boot half from being deformed radially outward. A ring is arranged, and the holding ring is fixed by the folded-back sleeve portion being closely attached to the outer surface of the holding ring. And universal joint boots. 2. The universal joint boot according to claim 1, wherein a bead is provided at a tip of the folded sleeve.