JPH0324898Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a tightening structure for a boot of a universal joint, and in particular, to a tightening structure for a boot of a universal joint that can be securely fixed to a universal joint.

[Prior art and its problems]

Generally, the state in which the boot is attached to the universal joint is as shown in FIG.

That is, the universal joint 20 has an inner joint member 21
and the outer joint member 22 provided on the outside of the inner joint member 21.
A steel ball 25 held by a retainer 24 is positioned, thereby forming a universal joint 20 in which an outer joint member 22 and an inner joint member 21 are rotatable.

The inner joint member 21 of the universal joint 20 is provided with a driving shaft 26 by spline connection, and the outer joint member 22 is integrally provided with a driven shaft 27.

Then, the drive side shaft 2 of the universal joint 20
The boot 28 provided on the 6 side has a cylindrical shape, and has an enlarged opening edge 29 at one end, an opening edge 30 at the other end, and
A bellows portion 31 is formed between the enlarged opening edge 29 and the opening edge 30, and is further formed of an elastic body through which the driving shaft 26 passes.

The boot 28 as described above is fixed to the outer joint member 22 by a boot fixing band 32 located outside the enlarged opening edge 29 thereof.

As shown in FIGS. 6 and 7, this boot fixing band 32 is made by bending a long steel plate 33 into an annular shape, overlapping both ends thereof, and placing a curved member 34 thereon.
and form a ring shape that unites them, and
Opposing upright pieces 35 are provided at predetermined positions on the long steel plate 33.

When fixing the boot 28 to the universal joint 20 using the boot fixing band 32 as described above, first insert the boot 28 or the universal joint 20 into the ring of the boot fixing band 32, and then insert the boot 28 or the universal joint 20 into the universal joint 20. The enlarged opening edge 29 of the boot 28 is fitted onto the outer joint member 22 of the boot 20 .

Then, attach the boot fixing band 32 to the boot 28.
The curved member 34 forming the boot fixing band 32 is folded back, which is located outside the enlarged opening edge 29, thereby reducing the size of the annular ring formed by the long steel plate 33. With universal joint 2
Fixing of the enlarged opening edge 29 of the boot 28 to the universal joint 20 is completed by sandwiching the enlarged opening edge 29 of the boot 28 with the outer joint member 22 of the universal joint 20 and wrapping the curved member 34 with the upright piece 35. It is something to do.

However, in the boot fixing band 32 of the universal joint 20 configured as described above, the surface pressure compressing the enlarged opening edge 29 is approximately constant as shown in FIG. , since its size is relatively small, the grease inside the universal joint 20 leaks to the outside, significantly reducing the internal lubrication performance, or the internal air leaks to the outside, reducing the internal pressure of the boot, which causes the boot to There is a risk that the boot may be dented or damaged, and furthermore, there is a risk that dust may enter the inside of the boot from the outside, which may impede the sealing function.

This invention solves the problems of the conventional ones as described above, and its purpose is to provide a tightening structure for the boot of a universal joint that can increase the sealing function when attached to the universal joint. do.

[Means for solving problems]

In order to solve the above-mentioned problems, this invention provides a tightening structure for a boot of a universal joint that uses a boot fixing band to tighten the boot that is fitted into the universal joint. Annular protrusions are provided at two opposing locations on the inner and outer circumferential surfaces of the boot fixing band, and the boot fixing band is long and curved in the lateral direction to form a curved portion, and the boot fixing band is formed into a curved portion. This universal joint boot tightening structure is characterized in that only the annular protrusion of the boot comes into contact with the band when the boot is tightened.

[Effect]

By adopting the above-mentioned means, this idea
This means that the sealing function when the boot is attached to the universal joint can be significantly improved.

〔Example〕

Embodiments of this invention shown in the drawings will be described below.

FIG. 1 shows a universal joint boot tightening structure according to this invention, and this boot fixing band 1 is of the same type as that shown in FIGS. 6 and 7, but in the lateral direction. has two curved parts 2 and 3, and these curved parts 2 and 3 are annular.

Further, the enlarged opening edge 29 of the boot 28 is provided with annular protrusions 4a and 4b at two corresponding locations on its inner and outer peripheries, and these annular protrusions 4a and 4b are connected to the boot fixing band 1. The outer joint member 22 of the universal joint 20 is provided with a recess 5 on the outer peripheral surface thereof to receive the annular protrusion 4b of the boot 28.

Then, as mentioned above, the two annular curved parts 2,
When attaching the boot 28 to the outer joint member 22 of the universal joint 20 using the boot fixing band 1 having the boot fixing band 1 formed with the boots 28, Position and tighten as usual.

Then, the surface pressure at the time of tightening becomes as shown in FIG.
A large surface pressure acts at positions a and 4b, thereby increasing the sealing function. Furthermore, since the boot fixing band 1 is curved in its lateral direction, the band itself has a spring effect, increasing the sealing effect.

FIG. 3 shows another embodiment of this invention, in which the cross section of the boot fixing band 1 in the lateral direction is formed by one curved part 6.

When fixing the boots 28 using the boot fixing band 1 configured in this way, the boots 28
An annular protrusion 4a provided on the enlarged opening edge 29 of
When the annular protrusion 4a is placed in contact with the other parts and then tightened, a peak of surface pressure occurs because the annular protrusion 4a is pressed to a greater extent than other parts. It is possible to increase the sealing function.

Therefore, in any of the embodiments, the boot fixing band 1 is connected to the curved portions 2, 3, 6.
The spring effect is exerted to hold the boot 28, and the curved portion 2,
Together with the fact that 3 and 6 are in contact with each other, the sealing function is increased.

In addition, in the above embodiment, a fixing band for boots which is formed into a ring shape from the beginning and whose ring can be compressed by folding back the curved member was shown, but the present invention is not limited to this. Of course, it may be of the type that is made into a ring shape after being attached, or of the type that is caulked.

Further, in the above embodiment, the case where the enlarged opening edge of the boot is fixed has been described, but it goes without saying that it may be used to fix other edges. Although the annular protrusion is provided on the surface and the outer circumferential surface, it may be provided on either one of the annular protrusions.

[Effect of idea]

By configuring this idea as described above,
When attached to a universal joint, the boot fixing band is curved and has a spring effect, as there are protrusions at two opposing locations on the inner and outer circumferential surfaces. As a result, the surface pressure of the protruding portion is significantly increased, which has the excellent effect of significantly improving the sealing function between the protrusion and the universal joint.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing the tightening structure of a universal joint boot according to this invention, Fig. 2 is a diagram showing the surface pressure during tightening, Fig. 3 is a schematic diagram showing another embodiment, and Fig. 4 is a conventional one. FIG. 5 is a diagram showing the surface pressure during tightening, and FIGS. 6 and 7 are diagrams showing the boot fixing band of this invention and the conventional case. 1, 32...Fixing band for boots, 2, 3, 6
...Curved portion, 4a, 4b...Annular protrusion, 5...
Recessed portion, 20... Universal joint, 21... Inner joint member, 22... Outer joint member, 23... Blank space, 24...
...Retainer, 25... Steel ball, 26... Drive side shaft, 27... Driven side shaft, 28... Boot, 29... Enlarged opening edge, 30... Opening edge,
31... Bellows part, 33... Steel plate, 34... Curved member, 35... Standing piece.

Claims (1)

[Scope of utility model registration request] A universal joint boot tightening structure in which a boot 28 fitted into a universal joint 20 is tightened using a boot fixing band 1, wherein the boot 28 includes:
Two opposing inner and outer peripheral surfaces of the opening edge
Annular protrusions 4a and 4b are provided at several locations, and the boot fixing band 1 is made long and curved in the transverse direction to form curved portions 2, 3, and 6, and the boot 28 is fixed with the band 1. A universal joint boot tightening structure characterized in that only the annular protrusions 4a and 4b of the boot 28 come into contact with the band 1 when tightened.