JPH0731409U - Flat tire - Google Patents

Abstract

(57) [Summary] [Purpose] To improve riding comfort and reduce rolling friction in puncture-less tires. A tire main body 2 is mounted on a rim 3 of a wheel 1, and has a ring-shaped first tire member 10, a second tire member 11, and a plurality of circumferentially continuous shock absorbing closed cavities. And a part 15. The first tire member 10 is
It is attached to the rim 3. The second tire member is an elastic annular member fixed to the outer peripheral side of the first tire member 11. The closed cavity 15 is formed on the boundary surface between the first tire member 10 and the second tire member 11, and is arranged in a plurality of rows so that the cross-sectional area thereof is substantially constant.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 TECHNICAL FIELD The present invention relates to a puncture tire, and more particularly to a puncture tire mounted on a wheel rim.

[0002]

[Prior art and its problems]

 As this type of puncture tire, for example, a solid tire disclosed in USP 4,446,903 is known. This solid tire is made of foamed urethane rubber having a tread on the outer periphery, and a plurality of beads for preventing elongation due to centrifugal force are embedded inside the inner periphery of the tire. In this solid tire, if the cushioning properties of urethane foam rubber are improved to improve riding comfort, the amount of deformation on the ground contact surface increases and internal friction increases. When the internal friction increases, the elastic hysteresis loss increases, and the rolling friction increases in accordance with this elastic hysteresis loss. For this reason, power loss during traveling becomes large, and a large amount of power is required for traveling.

As a conventional technique for reducing rolling friction, a solid tire disclosed in Japanese Utility Model Laid-Open No. 55-127603 is known. In this solid tire, rubber with a substantially triangular cross section is fixed to the rim so that its apex contacts the ground, and the ground contact area is reduced to reduce rolling friction. However, since the solid tire has a triangular cross-section, it is difficult to improve the riding comfort, and it can be mainly used only for narrow applications such as racing bicycles.

An object of the present invention is to provide a puncture-less tire with good riding comfort and low rolling friction.

[0005]

[Means for Solving the Problems]

 A puncture-less tire according to the present invention comprises an annular first tire member, a second tire member, and a shock absorbing means. The second tire member is an annular member made of an elastic material that is fixed to the outer peripheral side of the first tire member. The shock absorbing means is formed between the first tire member and the second tire member, and is arranged in a plurality of rows in a circumferential direction such that a cross-sectional area when radially cut from the tire center is substantially constant. It has a series of closed cavities.

[0006]

[Action]

 In the puncture-less tire according to the present invention, a plurality of circumferentially-closed closed cavities arranged in a plurality of rows such that the cross-sectional area when radially cut from the tire center is substantially constant and the first tire member and It is formed between the second tire member. Therefore, the internal friction during elastic deformation is smaller than that of solid tires, and elastic hysteresis loss is reduced. The amount of decrease in the elastic hysteresis loss here is substantially constant because the cross-sectional area of the closed cavity is substantially constant. As a result, rolling friction is reduced at a substantially constant rate compared to solid tires. Further, since it is not necessary to limit the shapes of the first tire member and the second tire member, the riding comfort can be improved. Furthermore, since a plurality of closed spaces are arranged, even if a hole is opened in one of them, it will not be punctured.

[0007]

【Example】

 In FIG. 1, a wheel 1 according to an embodiment of the present invention is used for a bicycle having a width of 26 inches × 1 3/8 inches, for example, a tire main body 2 and a rim for mounting the tire main body 2. 3, a hub 5 arranged at the center of the wheel 1, and a large number of spokes 4 connecting the hub 5 and the rim 3.

As shown in FIG. 2, the tire body 2 includes a first tire member 10 arranged on the rim 3 side and a second tire member 10 fixed to the outer peripheral side of the first tire member 10 and having a substantially semicircular cross section. The tire member 11. The first tire member 10 is made of urethane rubber having a low elastic modulus, and the second tire member is made of urethane foam rubber having high flexibility. Further, the first tire member 10 is composed of a mounting portion 12 having a substantially rectangular cross section fitted into the rim 3, and an inner peripheral portion 13 continuous from the mounting portion 12 in a substantially semicircular cross section. A tread 14 is formed on the outer peripheral portion of the second tire member 11. A closed cavity 15 having a semi-elliptical cross section is formed at the boundary surface between the second tire member 11 and the first tire member 10.

As shown in FIGS. 3 and 4, the closed cavity 15 has a crescent-shaped vertical cross section and a flat rugby ball-shaped cross section. The closed cavities 15 are arranged in a staggered manner in three rows in the circumferential direction of the second tire member 11. In addition, the cross-sectional area of the closed cavity 15 when radially cut from the tire center is arranged to be substantially constant.

Next, the operation when the wheel 1 rotates will be described. When the wheel 1 rotates, the ground contact portion elastically deforms. Along with this, elastic hysteresis loss occurs due to internal friction, but since the closed cavity 15 is formed inside, elastic hysteresis loss is smaller than that of a solid tire. The amount of decrease in this elastic hysteresis loss is substantially constant because the cross-sectional area of the closed cavity 15 is constant. As a result, rolling friction is smaller than that of a solid tire. Therefore, if this is used for a bicycle or the like, the power loss during traveling is reduced and the bicycle can be run with a light force.

Further, since a large number of closed spaces 15 are provided, even if one closed space 15 is in a parked state, it is possible to continue traveling without being affected by it as a whole. Therefore, puncture performance can be exhibited. Further, since the shape of the tire is not limited, the ride comfort can be improved by appropriately setting the size of the space cavity portion 15 and the foaming rate of the urethane foam rubber. In addition, the first tire member 10 on the inner peripheral side has a low elastic force and is difficult to stretch even if centrifugal force is applied during traveling. Therefore, the tire body 2 can be prevented from coming off the rim.

[Other Embodiments] (a) The shape of the closed space is not limited to the above-mentioned embodiment, and may be any shape as long as the cross-sectional area is substantially constant. (B) The formation position of the closed cavity is not limited to the above-mentioned embodiment, and may be any position between the first tire member and the second tire member. (C) The present invention is not limited to bicycle wheels, but can be applied to other vehicles such as automobiles.

[0013]

[Effect of device]

 In the puncture-type tire according to the present invention, a plurality of tires arranged in a circumferential direction between the first tire member and the second tire member are arranged so that the cross-sectional area when radially cut from the tire center is substantially constant. Since the closed cavities are formed so that the cross-sectional area when they are radially cut from the center of the tire is substantially constant, internal friction during elastic deformation is reduced. It is smaller than solid tires and elastic hysteresis loss is reduced. The reduction amount of elastic hysteresis loss here is substantially constant because the cross-sectional area of the closed cavity is substantially constant. As a result, rolling friction is reduced at a substantially constant rate as compared with a solid tire. Further, since it is not necessary to limit the shapes of the first tire member and the second tire member, it is possible to improve the riding comfort. Furthermore, since a plurality of closed spaces are arranged, even if one of them has a hole, it will not be punctured.

[Brief description of drawings]

FIG. 1 is a side view of a wheel adopting an embodiment of the present invention.

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

FIG. 3 is a partial sectional view taken along the line III-III in FIG.

FIG. 4 is a partial sectional view taken along the line IV-IV of FIG.

[Explanation of symbols]

 2 Tire Main Body 10 First Tire Member 11 Second Tire Member 15 Sealed Cavity

Claims (1)

[Scope of utility model registration request] 1. A puncture-less tire mounted on a rim of a wheel, comprising: an annular first tire member; and an elastic annular second tire member fixed to an outer peripheral side of the first tire member. A plurality of seals formed between the first tire member and the second tire member and arranged in a plurality of rows so that the cross-sectional area when radially cut from the tire center is substantially constant and continuous in the circumferential direction. A punctureless tire including: a shock absorbing means having a hollow portion;