JPH092005A - Air seal device for spoke wheels for tubeless tires - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a highly durable air seal device capable of effectively preventing air leakage even when a tubeless tire is mounted on a spoke wheel. [Structure] A protective strap 11 fitted to an outer peripheral groove 8a of a center drop portion 8 to which a spoke 4 is connected to a rim 2.
Then, a partition sheet 12 whose central portion is supported by the protective strap 11 and whose both end portions cover the left and right bead seat portions 7 is attached.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rim having a pair of left and right bead seat portions and a center drop portion connecting the bead seat portions, and a hub arranged at the center of the rim.
The present invention relates to an air seal device for a spoke wheel for a tubeless tire including a center drop portion and a large number of spokes connecting between hubs.

[0002]

2. Description of the Related Art Generally, in a spoke wheel, a center drop portion of a rim is provided with an insertion hole for a nipple threadably connected to the spoke. Therefore, when a tubeless tire is used, the air is passed through the insertion hole. An air seal device is required to prevent outflow.

Conventionally, as such an air seal device, a rubber diaphragm for continuously covering both bead seat portions and center drop portions of the rim is attached to a rim, and a nipple between an air chamber and a center drop portion in a tubeless tire is mounted. There is known a device which blocks the space between the insertion hole and the insertion hole (see Japanese Utility Model Publication No. 35-29401).

[0004]

By the way, since the diaphragm directly covers the outer peripheral surface of the center drop of the rim at the central portion thereof, it is strongly pressed against the outer peripheral surface of the center drop by the air pressure in the tire, so that the nipple, etc. There is a possibility that the sealability may be damaged due to damage during long-term pressure contact.

It is an object of the present invention to provide an air seal device for a spoke wheel for a tubeless tire, which is capable of ensuring a good sealability for a long time without the above-mentioned fear.

[0006]

In order to achieve the above object, the present invention provides a rim, a protective strap fitted in an outer peripheral groove of a center drop portion, and a central portion supported by the protective strap. A partition sheet for covering both bead seat portions is provided so that both left and right end portions are in close contact with the left and right bead portions of the tubeless tire.

[0007]

According to the above feature, the partition sheet blocks the air chamber in the tire from the center drop portion of the rim, thereby reliably preventing air leakage. Moreover, since the partition sheet is supported by the protective strap fitted to the center drop portion, excessive deformation due to air pressure is suppressed, and contact with the nipple is cut off.

On the other hand, even if the protective strap is damaged by contact with a nipple or the like, it does not have any adverse effect on the partition sheet which is separate from the protective strap.

Further, the partition sheet and the protective strap are
It is possible to use different materials adapted to each function.

[0010]

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, a spoke wheel 1 for a motorcycle comprises a rim 2, a hub 3 arranged at the center of the rim 2, and a large number of spokes 4 connecting the rim 2 and the hub 3. The tubeless tire 5 is attached to the rim 2.

As shown in FIG. 2, the rim 2 includes a pair of left and right flange portions 6 and 6, a pair of bead seat portions 7 and 7 connected to the roots of the flanges 6 and 6, and a space between the bead seat portions 7 and 7. And a center drop unit 8 connecting the two. The center drop portion 8 is curved toward the hub 3 so as to form an outer peripheral groove 8a, and a large number of hemispherical nipple seat portions 9 and 9 arranged in the circumferential direction are formed on the bottom wall of the outer peripheral groove 8a. Are provided, and each nipple seat 9 has a nipple insertion hole 9a at the center.

The head of the nipple 10 inserted into the nipple insertion hole 9a is seated on the nipple seat 9, and is screwed to the outer end of the spoke 4. Thus, a large number of spokes 4, 4 ... and the center drop portion 8 of the rim 2
Are linked.

A rubber-made endless annular and thick protective strap 11 is fitted in the outer peripheral groove 8a of the center drop portion 8 so as to be fitted therein. Further, a strip-shaped and thin partition sheet 12 is wound so as to continuously cover the outer peripheral surfaces of the elastic strap 11 and the left and right bead seat portions 7, 7, and both end portions 12a, 12a thereof are shown in FIG. As described above, they are overlapped with each other, and are joined by welding, welding, adhesion or the like as necessary. In the illustrated example, the partition sheet 12 is made of a metal or synthetic resin band material having sealability and wear resistance, but it may be made of endless annular rubber.

When the tubeless tire 5 is mounted on the rim 2, the left and right bead portions 5a, 5a come into close contact with both bead seat portions 7, 7 of the rim 2 via the partition sheet 12.

As shown in FIG. 3, the protective strap 11 has a flange 1 formed at the inner end of the valve cylinder 14 of the air valve 13.
4a is embedded and baked. Further, the protective strap 11 is formed with a seal boss 15 which penetrates the through hole 16 of the partition sheet 12 and seals the peripheral edge of the through hole 16, and the air passage 18 in the valve cylinder 14 is connected to the seal boss 15 in the air chamber in the tire 5. 1
A through hole 17 communicating with 9 is provided. The valve cylinder 14 is inserted into the mounting hole 22 of the center drop portion 8 and fixed to the center drop portion 8 by a pair of inner and outer nuts 20 and 21.
Thus, high-pressure air can be supplied to the air chamber 19 through the air valve 13 without leakage.

Next, the operation of this embodiment will be described.

Since the partition sheet 12 interposed between the bead seat portions 7 and 7 of the rim 2 and the bead portions 5a and 5a of the tire 5 is formed thin, the bead portions 5a and the bead portions 5a and 5a are formed in accordance with the tightening force of each bead portion 5a. Familiar with both bead seats 7, ensuring airtightness between them. Further, since the partition sheet 12 blocks between the air chamber 19 in the tire 5 and the center drop portion 8 of the rim 2, the air in the air chamber 19 is prevented from leaking out from the nipple insertion hole 9a of the center drop portion 11. To prevent.

Moreover, since the center portion of the partition sheet 12 covering the center drop portion 8 is in contact with the outer peripheral surface of the protective strap 11 fitted in the outer peripheral groove 8a of the center drop portion 8,
Even if the central portion of the partition sheet 12 is strongly pressed inward in the radial direction by the pressure of the air chamber 19, it is supported by the protective strap 11 in a buffer manner to prevent excessive deformation, and may come into contact with the nipple 10. Absent. As a result, the durability of the partition sheet 12 becomes extremely high.

On the other hand, the protective strap 11 is used for the nipple 1.
Even if it is damaged due to contact with 0, the partition sheet 12 which is a separate body from it is not adversely affected by the seal.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the gist of the invention. For example, in the above embodiment, the protective strap 11
Was formed endlessly, but it can also be formed as an end.

[0022]

As described above, according to the present invention,
A protective strap that fits into the outer peripheral groove of the center drop part, and the central part is supported by this protective strap,
Since a partition sheet covering both bead seats is provided so that both left and right ends are in close contact with the left and right bead parts of the tubeless tire, a partition that blocks between the air chamber inside the tire and the center drop part of the rim. The seat is extremely durable because it is supported by the protective strap of the center drop part to prevent excessive deformation, the contact with the nipple is cut off by the protective strap, and it is not adversely affected even if the protective strap is damaged. Is obtained, and a good air-sealing function can be exhibited for a long period of time. Moreover, since the partition sheet and the protective strap can be made of materials adapted to their respective functions, the requirements for performance and cost can be simultaneously satisfied.

[Brief description of the drawings]

FIG. 1 is a side view showing a spoke wheel according to an embodiment of the present invention with a tubeless tire attached.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 1;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 2;

[Explanation of symbols]

 1 spoke wheel 2 rim 3 hub 4 spoke 5 tubeless tire 5a bead part 7 bead seat part 8 center drop part 8a outer peripheral groove 9 nipple seat part 9a nipple insertion hole 10 nipple 11 protective strap 12 partition sheet 19 air chamber

Claims (1)

[Claims] 1. A pair of left and right bead seat portions (7) and a center drop portion (8) connecting between these bead seat portions (7).
A rim (2), a hub (3) arranged at the center of the rim (2), and a large number of spokes (4) connecting the center drop portion (8) and the hub (3). In the spoke wheel for a tubeless tire, the rim (2) is provided with an outer peripheral groove (8) of the center drop portion (8).
The protective strap (11) fitted to a) and the central portion are supported by this protective strap (11), and both left and right ends are in close contact with the left and right bead portions (5a) of the tubeless tire (5). An air seal device for a spoke wheel for a tubeless tire, characterized in that a partition sheet (12) for covering both bead seat portions (7) is provided on the.