JP2003222240A - Split boot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a split boot 1 excellent in connecting strength and a sealing property of a joint face 3 and having good assembly workability. <P>SOLUTION: A pair of abutting portions 4, 5 mutually brought into abutment at the joint face 3 extending in an axial direction is disposed to a bellows-like boot main body 2. A belt-like connecting member 6 are attached to cover the abutting portions 4, 5 so that the abutting portions 4, 5 are mutually connected. Recess groves 7 recessed to the inside in a diameter direction extends in an axial direction in the abutting portions 4, 5, and a pair of projection streaks 9 fitted in the recess grooves 7 are extended in the axial direction. Fitting pieces 11 partially expanded in a circumference direction extend from the projection streaks 9, and fitting grooves 12 to which the fitting groove 11 fit extend in an axial direction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bellows-like boot for enclosing and sealing a universal joint or the like on a shaft such as a drive shaft of an automobile. The present invention relates to split-type boots that are butted against each other at mating surfaces that extend toward each other.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 9-96362 discloses an example of a split type boot that can be detachably attached to a universal joint or the like later. This split boot has a bellows-shaped boot body that is butted against each other at a mating surface that extends in the axial direction, and a band-shaped band that is attached from the outer peripheral side so as to cover the butted portion and that joins the butted portion. ing. The boot body is provided with a plurality of notches that extend in the circumferential direction across the mating surface and are intermittently recessed in the axial direction, and the band has protrusions that fit into the notches and are intermittent in the axial direction. It is installed in multiple places.

However, the split boot as disclosed in this publication has the following problems. First, since the joints between the protrusions and the notches are intermittently provided in the axial direction, and these joints are discontinuous in the axial direction, the joint strength and sealability (airtightness) of the portion without the joints can be improved. , Liquid tightness) is difficult to secure. For example, when the bellows portion of the split boot bends in the axial bending direction, the mating surface is likely to open at the portion without the joint portion, and it is difficult to ensure sufficient sealing performance. Such a decrease in the sealing property is not preferable because it may lead to leakage of grease filled in the boot or foreign matter such as water or dust may enter the boot from the outside.

Second, when the band is attached to the boot body, since the outer peripheral surface of the band projects radially outward from the outer peripheral surface of the boot body, the split boot is bent in the axial bending direction. In this case, adjacent mountain-shaped portions of the band that bends in a bellows shape are likely to locally contact each other, and wear may be concentrated in this portion (uneven wear), resulting in a decrease in durability. is there. Therefore, in order to improve the durability, it is inevitable to limit the shape such as increasing the pitch of the bellows or reducing the number of bends of the bellows.

Thirdly, since a plurality of connecting portions between the convex portion of the band and the notch portion of the boot body are provided intermittently in the axial direction, when the band is assembled to the boot body, like a button, It is necessary to match the positions of the convex portion and the notch portion with each other for each individual joint portion, and then to fit the both, so that the assembling work is very complicated. In addition, since the convex portion of the band has a solid shape with no void, it is difficult to elastically deform and it is difficult to insert it into the cutout portion.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is a novel split boot having excellent bonding strength and sealing property on mating surfaces and good workability in assembling. The main purpose is to provide.

[0007]

A split boot according to the present invention comprises a boot body which is formed of a flexible material in a bellows shape and has a pair of butting portions which are butted against each other at mating surfaces extending in the axial direction. And a connecting member which is formed of a flexible material in a substantially strip shape and which is mounted so as to cover the pair of abutting portions with the abutting surface sandwiched therebetween and which connects the abutting portions to each other. Each abutting portion is formed with a concave groove that is recessed radially inward in the axial direction, and the connecting member is formed with a pair of convex stripes that are fitted in the concave groove in the axial direction. There is. A fitting piece that partially projects in the circumferential direction is axially formed in the ridge, and a fitting groove into which the fitting piece is fitted is axially formed in the concave groove. Has been done.

As described above, according to the present invention, the pair of abutting portions and the connecting member are formed with the recessed groove and the ridge which are fitted to each other in the axial direction, and the abutting portion and the connecting member are axially formed. Since the joining is performed continuously and without interruption, the joining strength and sealing property at the mating surfaces are made uniform in the axial direction. Therefore, even when the bellows portion is bent in the axial bending direction, the sealing performance is not impaired. Further, since the concave groove and the convex strip that are fitted to each other are formed to extend in the axial direction, if the concave groove and the convex strip are fitted in one place like a chuck, both of them are axially extended from that portion. It can be easily fitted along with it, and it has excellent workability in assembly. Furthermore, since the fitting piece and the fitting groove that fit with each other are formed to extend in the axial direction in the ridge and the groove, it is difficult to combine them by bending in a bellows shape. It is possible to secure good bond strength and sealability.

[0009]

According to the present invention, it is possible to obtain a novel split boot having excellent bonding strength and sealing property at the mating surfaces and good workability in assembling.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A preferred embodiment of a split boot according to the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, the split boot 1 is used for a constant velocity joint or the like of an automobile, and has a boot body 2 having a substantially cylindrical bellows shape. The boot body 2 is integrally molded with a flexible synthetic resin (or rubber or the like), and has one small-diameter open end 2a to the other large-diameter open end 2b.
The diameter gradually increases toward.

As shown in FIGS. 3 and 4, the boot body 2
A pair of abutting portions 4 and 5 which are abutted to each other in the circumferential direction by a single mating surface 3 extending in the axial direction are formed in the circumferential wall of the to extend in the axial direction. You can do it. A substantially band-shaped connecting member 6 is provided so as to cover these butting portions 4 and 5.
By attaching the to the abutting portions 4 and 5 from the outer peripheral side, the abutting portions 4 and 5 are coupled to each other. The connecting member 6 is integrally molded with a synthetic resin (or rubber or the like) which is a flexible material, and as shown in FIG. 2, is preliminarily bent into a bellows shape like the boot body 2. ing.
The abutting portions 4 and 5 are substantially symmetrical with respect to the center line L (see FIG. 3) extending in the diametrical direction, except for the mating surface 3 that is bent in a crank shape. Similarly, the connecting member 6 is also substantially symmetrical with respect to the center line L. Therefore, similar portions with the center line L interposed therebetween will be described with the same reference numerals.

Referring to FIG. 4, in each of the abutting portions 4 and 5, a concave groove 7 which is recessed radially inward is formed so as to extend in the axial direction. The groove 7 is formed in a substantially box shape that is open outward in the radial direction. Further, each of the abutting portions 4 and 5 has a central thick portion 8 thickened with respect to the concave groove 7, and a mating surface 3 is formed on each central thick portion 8. On both sides in the circumferential direction of the connecting member 6, a pair of ridges 9 fitted into the above-mentioned groove 7 are formed.
Is extended in the axial direction. That is, the connecting member 6 has a substantially U-shaped section (channel shape) in which the ridges 9 are formed on both sides of the central thin portion 10 that fits into the central thick portion 8.

As described above, the pair of abutting portions 4, 5 and the connecting member 6 are formed with the recessed groove 7 and the ridge 9 which are fitted to each other in the axial direction, and are connected to the abutting portions 4, 5. Since the member 6 and the member 6 are continuously coupled in the axial direction without interruption, the bonding strength and the sealing property at the mating surface 3 are uniformly and stably imparted in the axial direction. Further, since the concave groove 7 and the convex strip 9 which are fitted to each other are formed to extend in the axial direction, if the concave groove 7 and the convex strip 9 are fitted together at one place like a chuck, both parts will be inserted from that portion. 7 and 9 can be easily fitted along the axial direction, and the workability of assembling is excellent.

A fitting piece 11 partially extending in the circumferential direction is formed on the outer circumferential portion of the ridge 9 so as to extend in the axial direction. On the other hand, on the outer side in the circumferential direction of the concave groove 7, the above-mentioned fitting piece 1 is provided.
A pair of fitting grooves 12 into which 1 is fitted is formed to extend in the axial direction. In other words, the outer circumferential surface of the concave groove 7 is bent and formed in a stepped shape (stepped shape) into which the outer peripheral side enters the connecting member 6 so that the step surface 13 facing inward in the radial direction is formed. ing. The back surface 14 of the fitting piece 11 faces and abuts against the step surface 13. As a result, the connecting member 6 can be securely attached without accidentally coming off from the abutting portions 4 and 5, and a sufficient bonding strength and sealing performance can be obtained even though it has a bellows shape in which it is difficult to secure the bonding strength and sealing performance. You can

FIG. 5 shows a procedure for assembling the split boot 1. First, as shown in, both butting portions 4 and 5 of the boot body 2 are butted to each other at the mating surface 3. Next, as shown in, the convex strip 9 of the connecting member 6 is inserted into the concave groove 7 of the abutting portions 4 and 5. In order to improve the insertability of the ridge 9 into the concave groove 7, the following contrivances have been made.

First, the ridge 9 is fitted with a slit-like void portion 15 of a predetermined volume, which is opened toward the insertion tip side (lower side in FIGS. 4 and 5) at a substantially central portion in the circumferential direction. It is formed adjacent to the joint piece 11. As shown in FIG. 5, the ridge 9 can be easily elastically deformed so that the void 15 is reduced (closed), and thus the workability of inserting the ridge 9 is improved.
When the ridge 9 is completely inserted, the ridge 9 expands in the circumferential direction due to the restoring force of the ridge 9 to return to the initial shape having the void portion 15 having a predetermined volume, as shown in FIG. It elastically deforms to open, the inner peripheral wall 16 of the ridge 9 is pressed against the central thick portion 8, and the fitting piece 11 is fitted into the fitting groove 1.
By fitting with the fitting member 2, the joining strength of the mating surface 3 and the sealing property are sufficiently ensured, and the connecting member 6 is securely attached without accidentally coming off.

Secondly, the fitting pieces 11, which are both side walls in the circumferential direction of the ridge 9, are formed in a taper shape that tapers toward the insertion tip side and widens toward the rear surface 14, as shown in FIG. As shown in (1) and (2), it has a shape that is easy to insert and difficult to remove. Thirdly, the above-mentioned void 15 has a substantially triangular cross-section that widens toward the insertion tip side (lower side in FIG. 5) so that the insertion tip side of the ridge 9 is sufficiently shrunk to facilitate insertion. .

Referring again to FIG. 4, the outer peripheral surface of the connecting member 6 mounted on the boot body 2 is smoothly continuous with the outer peripheral surface of the boot body 2 other than the connecting member 6. In other words, the outer peripheral surface of the connecting member 6 is not projected or recessed with respect to the outer peripheral surface of the boot body 2, and has substantially the same circular arc surface. Therefore, when the bellows portion of the split boot 1 bends in the axial bending direction, the connecting member 6 bends in the same manner as the boot body 2, so that local uneven wear does not occur and the durability is excellent. ing. As a result,
As described above, there is no restriction on the shape such as increasing the pitch of the bellows in order to prevent uneven wear, and the degree of freedom of the shape is high.

As described above, because the outer peripheral surfaces of the connecting member 6 and the boot body 2 are substantially the same, and the concave groove 7 for receiving the above-mentioned convex strip 9 is provided, the abutting portions 4, 5 are formed.
Is thicker inward in the radial direction than the general portion of the boot body 2. More specifically, the inner peripheral surfaces of the butted portions 4 and 5 are substantially flat surfaces orthogonal to the center line L.

The mating surface 3 is not a diametrically extending plane, but is bent in a crank shape. That is, mating surface 3
Is formed in a stepped shape having a step surface 3a that is substantially orthogonal to the center line L. As a result, the butt portions 4, 5 are prevented from being displaced from each other in the radial direction, and even if the butt portions 4, 5 are displaced in a direction in which they are circumferentially separated from each other, the butt portion 4 is formed at the step surface 3a. , 5 may be maintained in a sliding contact state, and the sealing property thereof is further stabilized.

FIGS. 6-8 show modifications of the above-described embodiment of FIGS. 1-5, respectively. In the following modified examples, only parts different from the above embodiment will be described. In the example shown in FIG. 6, in addition to the above-described fitting piece 11 being formed on the outer circumferential portion of each protrusion 9 of the connecting member 6, the auxiliary hook is also attached to the inner inner portion of each protrusion 9. A stop piece 20 is formed. Similar to the fitting piece 11, the sub retaining piece 20 has a shape that tapers toward the insertion tip side (lower side in FIG. 6). Corresponding to this, in addition to the fact that the fitting groove 12 into which the fitting piece 11 fits is formed on one side in the circumferential direction of each recessed groove 7 formed in the butted portions 4 and 5, each recessed groove 7 A sub-engaging groove 21 into which the sub-engaging piece 20 is fitted is also formed on the other side in the circumferential direction. The sub retaining groove 21 is recessed in the central thick portion 8 where the mating surface 3 is formed. Here, it is desirable that the gap 15 has a wider width than that of the embodiment of FIGS. In this way, when the sub-engagement piece 20 and the sub-engagement groove 21 are additionally provided in the fitting piece 11 and the fitting groove 12, the ridge 9
The insertion workability does not deteriorate, and it becomes more difficult for the connecting member 6 to accidentally come off the boot body 2, and the sealing performance also improves.

In the example shown in FIG. 7, the mating surface 22 where the butted portions 4 and 5 are butted against each other is a flat inclined surface that is slanted with respect to the diametrical direction. In this case, the area of the mating surface 22 is increased and the sealing performance is improved as compared with the case where the mating surface extends in the diametrical direction. 4 and 5 can be displaced in the radial direction while being in contact with each other on the mating surface 22, and the sealing property thereof can be kept good.

In the example shown in FIG. 8, the abutting portions 4 and 5 are
To at least one side (butting part 5 in the example of FIG. 8),
Seal protrusions 23, 24 protruding from the mating surfaces 3, 22
Is extended in the axial direction. In this case, even if the abutting portions 4 and 5 are displaced in the circumferential direction away from each other, the seal projections 23 and 24 can ensure a predetermined sealing property, and the sealing property is further improved.

[Brief description of drawings]

FIG. 1 is a front view showing a split boot according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a single connecting member of the split boot.

3 is a sectional view taken along the line AA of FIG.

FIG. 4 is a cross-sectional view showing an enlarged part B of FIG.

FIG. 5 is an explanatory view showing an assembly procedure of the split boot.

FIG. 6 is a cross-sectional view showing another example of the concave groove of the boot body and the convex stripe of the connecting member.

FIG. 7 is a cross-sectional view showing another example of the shape of the mating surface of the boot body.

FIG. 8 is a cross-sectional view showing an example in which a seal protrusion protruding from the mating surface is provided.

[Explanation of symbols]

1 ... Split boots 2 ... Boots body 3… Mating surface 4, 5 ... Butt 6 ... Connecting member 7 ... Concave groove 9 ... ridge 11 ... Mating piece 12 ... Mating groove 15 ... void

Claims (5)

[Claims] 1. A boot body formed of a flexible material in a bellows shape and having a pair of butting portions abutting each other at a mating surface extending in an axial direction; and a boot body formed of a flexible material in a substantially strip shape. And a connecting member which is mounted so as to cover the pair of abutting portions with the abutting surface sandwiched therebetween, and which connects the abutting portions to each other, and each of the abutting portions is provided with a concave groove that is recessed radially inward. And a pair of convex strips that fit in the concave grooves are axially extended in the connecting member, and a fitting piece that partially projects in the circumferential direction is axially formed in the convex strips. And a fitting groove into which the fitting piece is fitted is formed in the concave groove so as to extend in the axial direction. 2. The split boot according to claim 1, wherein an outer peripheral surface of the connecting member is smoothly connected to an outer peripheral surface of the boot body in a state where the connecting member is attached to the abutting portion. 3. The split boot according to claim 1, wherein the convex strip is formed with a void portion that allows elastic deformation when the convex strip is inserted into the concave groove. 4. The split according to claim 1, wherein the mating surface is an inclined surface inclined with respect to the diametrical direction of the boot body or a stepped shape bent in a crank shape. boots. 5. The split boot according to claim 1, wherein at least one of the pair of butting portions is provided with a seal projection protruding from the mating surface.