JP2573034Y2 - Boot fixing structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for fixing a boot and a shaft portion of a device such as a joint housed inside the boot.

[0002]

2. Description of the Related Art Conventionally, as a fixing structure of this type, a boot seal structure described below has been proposed.

As shown in FIG. 6, a plurality of annular ridges 111 and an annular recess 112 are provided adjacent to each annular ridge 111 on the outer peripheral surface of a shaft 110 of the universal joint 108. And an annular projection 105 projecting from the inner peripheral surface of the end of the small diameter portion 103 provided at one end of the bellows portion 102 of the boot 101 is engaged with the ring-shaped stopper 10.
7, a notch 106 formed on the outer surface of the small diameter portion 103
(See J.61-91668)
Reference).

[0004]

[Problems to be Solved by the Invention] In the above conventional technology,
As shown in detail in FIG. 6, since the inner peripheral surface of the small diameter portion 103 is a mere cylindrical surface whose inner diameter does not change in the axial direction,
There is a problem that the work of externally fitting and holding the small diameter portion 103 at a predetermined position on the outer peripheral surface of the shaft 110 is troublesome.

[0005] In addition, a kerf is provided in the small diameter portion to prevent the stopper from being displaced, but this portion requires a thickness of 1.2 mm or more in order to obtain a sealing property. There is also a problem that the thickness of the small-diameter portion is increased by that much, the flexibility of the small-diameter portion is deteriorated as compared with the bellows portion, and the durability at the boundary between the two decreases.

The present invention has been made in view of the above-mentioned problems of the prior art, and is superior in airtightness and durability, and can surely position the fixed portion and the shaft portion. It is an object of the present invention to realize a boot fixing structure.

[0007]

In order to achieve the above object, a boot fixing structure according to the present invention comprises a bellows portion having cylindrical fixing portions formed at both ends, and a device housed therein. A fixing structure with a shaft portion, wherein the shaft portion of the device has a plurality of annular ridges formed at intervals from each other in the outer surface axial direction, and the shaft portion of the fixing portion to the fixing portion position which is fixed, along with being high outward protrusion than the outer surface of the bellows portion which projects outwardly on the outer surface of the site of the bellows portion toward, the said bellows portion closer An inward projection protruding inward is formed on an inner surface of the portion facing the outer projection formed at the portion.

[0008]

As described above, since the fixing portion fixed to the shaft has an inward projection formed on the inner surface thereof near the bellows portion, the positioning between the fixing portion and the shaft can be ensured. In addition to the above, the inner surface of the shaft portion is always in contact with the outer surface of the shaft portion.

[0009] In addition, the shaft portion of the fixing portion is fixed to the shaft portion.
Because the anchoring portion to be worn, high outward protrusion than the outer surface of the bellows portion that protrudes is formed to <br/> outward on the outer surface of the site of the bellows portion toward the correspondingly Flexibility can be ensured by setting the thickness of the portion of the fixing portion other than the portion where the outward projection is formed to be smaller than that of the conventional example.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

FIGS. 1 to 4 show a first embodiment of the present invention. FIG. 1 is a partially cutaway plan view, FIG. 2 is an enlarged sectional view showing a part of a fixing portion, and FIG. FIG. 4 is an explanatory view showing a disassembled state of the portion shown in FIG. 1, and FIG. 4 is a sectional view taken along line AA in FIG.

As shown in FIG. 1, the boot 1 is made of a flexible material such as rubber or plastics.
The bellows portion 2 has cylindrical fixing portions 3 and 4 formed at both ends. The boot 1 can be molded by a known molding method. In particular, in the case of plastic, injection molding, blow molding or injection blow molding can be used.

Each of the fixing portions 3 and 4 is inserted into a shaft portion 5 and an outer ring 7 of a device such as a joint housed in the boot 1, respectively.
They are fastened and fixed by bands 6A and 6B, respectively.

As shown in FIGS. 2 and 3, the fixing portion 3 fixed to the shaft portion 5 includes five annular ridges 5A formed at intervals from each other in the axial direction of the outer surface of the shaft portion 5. In order to prevent the band 6A from shifting in the axial direction, the outer protrusions 3A and 3B protruding outward are provided on the outer surface near the bellows portion and on the opening side in order to prevent the band 6A from shifting in the axial direction. It is formed in an annular shape.

An inner surface of a portion opposed to the outer protrusion 3A, which is higher than an outer surface of the bellows portion side formed on the outer surface of the portion closer to the bellows portion , has an inner surface. An inward projection 3 </ b> C protruding in the direction is formed in an annular shape to position the fixing portion 3 and the shaft 5.

As further shown in FIG. 4, in this embodiment,
Four outer projections 3A are formed at substantially equal intervals along the outer peripheral surface of the fixing portion 3. On the other hand, the inner protrusion 3C is formed as a single ring on the inner peripheral surface. For this reason, it is possible to secure the flexibility by setting the thickness of the portion of the fixing portion 3 other than the portion where the outward protrusions 3A and 3B are formed to be relatively thin.

FIG. 5 shows a second embodiment, and is a sectional view of a portion similar to FIG. In the present embodiment, contrary to the first embodiment, the outer protrusion 13A formed near the bellows portion is fixed to the fixing portion 1.
3 are formed in an annular shape on the outer peripheral surface, and four inwardly protruding portions 13C formed at portions opposed thereto are formed at substantially equal intervals along the inner peripheral surface of the fixing portion 13 having a small diameter.

In the first embodiment, the outward projection 3A is
In the second embodiment, each of the plurality of inward protrusions 13C is formed along the peripheral surface, but by forming in this way, especially when molding by blow molding, the resin periphery is improved. So that the outward projection 3A or
The inner protrusion 13C can be completely formed.

By the way, as shown in FIG. 3, the height A of the outer protrusion 3A, the height B of the inner protrusion 3C, and the tip of the fixed portion 3 are formed in the portion of the fixed portion 3 near the bellows portion 2. The height C of the outer protrusion, the height D of each annular ridge 5A, the height E of the fixed portion near the bellows, and the pitch F of each annular ridge 5A may be set to the following numerical values. .

A: 1.85 mm (preferable range: 0.8 to 2.2 mm) B: 0.3 mm (preferable range: 0.1 to 0.5 mm) C: 1.2 mm (preferable range: 1.0 to 2.5 mm) D) 0.2 mm (preferable range 0.1 to 0.5 mm) E: 1.35 mm (preferable range A> E, 0 to 2.0 mm) F: 3.0 mm (preferable range 2.4 to 3.5 mm) )

[0021]

Since the present invention is configured as described above, it has the following effects.

Since the inward protrusion protruding inward is formed at a position near the bellows portion on the inner surface of the fixing portion fixed to the shaft portion, the axial positioning of the fixing portion and the shaft portion is ensured. At the same time, the inner surface of the shaft always comes into contact with the outer surface of the shaft portion, so that the airtightness is improved.

In addition, the outer surface of the fixing portion near the bellows portion is higher than the outer surface of the bellows portion protruding outward.
Because have outward projections are formed, the outer collision of the fixing portion
By setting the thickness of the portion other than the portion where the portion is formed to be relatively thin, flexibility can be secured, and the durability of the fixed portion near the bellows portion can be improved.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view showing a first embodiment of a boot fixing structure according to the present invention.

FIG. 2 is an enlarged sectional view showing a part of a fixing portion fixed to a shaft portion of the first embodiment.

FIG. 3 is an explanatory view showing a state where the part shown in FIG. 2 is disassembled.

FIG. 4 is a sectional view taken along line AA of FIG.

FIG. 5 is a sectional view of a portion similar to FIG. 4 showing a second embodiment.

6A and 6B show a conventional example, in which FIG. 6A is a sectional view thereof, and FIG. 6B is an enlarged sectional view of a main part thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Boot 2 Bellows part 3,4 Fixing part 3A, 3B Outer protrusion 3C Inner protrusion 5 Shaft part 5A Annular protrusion 6A, 6B Band 7 Outer ring

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16J 15/52 F16J 3/04

Claims (1)

(57) [Scope of request for utility model registration] 1. A fixing structure of a boot consisting of a bellows portion having cylindrical fixing portions formed at both ends and a shaft portion of a device housed therein, wherein the shaft portion of the device has an outer surface shaft. a plurality of annular ridges formed at a mutually distance in the direction, while the fixing portion position which is fixed to the shaft portion of the fixing portion is outside the outer surface of the site of the bellows portion toward From the bellows side
And an inner protruding portion that protrudes inward is formed on an inner surface of a portion facing the outer protruding portion formed near the bellows portion. A boot fixing structure characterized in that: