JPH03148312A - Bicycle tire - Google Patents

Abstract

PURPOSE:To prevent a tread rubber layer from being torn off in an open side tire having a plurality of carcass layers wrapping a pair of bead portions, by arranging and embedding bias fabrics other than tire fabrics at least a side wall portion on the outside of carcasses. CONSTITUTION:A bicycle tire 1 has bead portions 3 consisting of bead wires and ropes made up of an organic or inorganic fabric, and the bead portions 3 embedded in bead rubbers 4 at both ear portions of the tire are wrapped with a 2 ply carcass 2(2a-2c) of tire fabrics which consists of bias cloths processingly attached to organic or inorganic fiber codes, and covered with rubber. Also, the carcass 2 portion surface located at tire ear portions is covered with ear cloths 5. At such a tire as this one, fabrics (the fabric group of a plain weaves, a twill fabric, a doup fabric) 8 other than the tire fabrics are arranged and embedded bias in adjacency to carcasses 2b, 2c on the outside of the carcass 2 of tire fabrics.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bicycle tire, and more particularly to an open-sided bicycle tire in which the sidewall portion is not coated with tread rubber. (Prior art) Conventionally, there are tires whose sidewalls are coated with rubber as a means of preventing damage to puncture resistance, cut resistance, etc. caused by the tread and sidewalls of tires. Although it is possible to improve the cut resistance of the sidewall portion of a tire, there is a problem in that the weight of the tire is generally increased and the running performance is significantly reduced. On the other hand, an open-sided tire (1°) with no rubber coating on the sidewall has a tire tread (6) and a tire tread (6) as shown in Figure 5.
and a canvas breaker (7) made of one or more plies of synthetic fibers having high tensile strength between the tread and the carcass.
It is widely known that the structure in which the (Problems to be Solved by the Invention) However, the conventional tire (1°) having the above-described oven side structure has various problems as listed below. That is, when the tire (l) contacts the road surface and deforms, the breaker (7), tread rubber (6) and carcass (2a)
(2b) Due to the difference in elastic modulus with (2e), the breaker (7) receives a large relative strain, and further
) and the breaker (7), and the breaker (7) and the carcass (2a), (2b), and (2c) due to the synergistic effect of the relative strain received from the difference in adhesive force between them. (7) is unable to maintain sufficient durability and suffers fatigue damage earlier than other components of the tire, resulting in separation between the tread rubber layer and the breaker, which have reduced adhesive strength, and the tread rubber layer and breaker. The breaker (7) is no longer able to maintain sufficient durability and suffers fatigue damage earlier than other components of the tire, resulting in separation between the tread rubber layer with reduced adhesive strength and the breaker, and the tread rubber (6) is subject to repeated strain not only in the radial direction but also in the axial direction, resulting in not only separation between the breaker and the tread rubber layer, but also separation between the tread rubber layer and the carcass at positions outside the breaker edge. The peeling phenomenon progresses, and eventually a fatal phenomenon occurs in which the entire tread rubber layer peels off, which may lead to the tire being scrapped. (2) The breaker (7), which suffers fatigue damage earlier than other constituent members of the tire, simultaneously loses its function as a cut-resistant layer, leading to a decrease in the cut-resistance of the tire. 0 In the case of open-side tires, it is impossible to make the breaker width wider than the tread width due to the appearance of the tire, and conventionally it has been limited to 0.9 times or less of the tread width. Therefore, the tire is in a state of being defenseless against the cutting action on a part of the shoulder. It had major structural defects such as: As a result of intensive studies aimed at solving the above-mentioned problems, the present invention focuses on the remarkable effect derived by partially modifying the structure of this type of tire. It is an object of the present invention to provide a bicycle tire that can greatly improve the disadvantages inherent in conventional tires of this type as described above by using a fabric other than woven fabric. (Means for Solving the Problems) - In order to achieve the above-mentioned object, the present invention is characterized by wrapping a pair of bead parts with a plurality of layers of carcass, and applying the carcass to the sidewall part and tread part of the tire. This bicycle tire is an extended open-sided tire in which a woven fabric other than a sudare woven fabric is arranged and added in a bias direction on at least the sidewall portion outside the carcass. These textiles include plain weave, satin weave, twill weave, mosier weave,
It is one of the textiles selected from a group of textiles such as Karami weave. (Example) Hereinafter, specific examples of the bicycle tire according to the present invention will be described using the drawings. FIG. 1 is a cross-sectional view of a bicycle tire (1) in which the present invention is implemented. A bead portion made of an inorganic fiber rope, and a bead bum (4) at both ear portions of the tire (1).
, (4) The bead portions (3), (3) embedded in the 2-ply sudare carcass (3) made of bias-like sudare cloth coated with rubber and bonded to organic or inorganic fiber cords (
2a), (2b), (2a), and (2e), and the surface of the carcass (2) located at the ear of the tire is
5) and (5). This sagging carcass (2) is located at the ear of the tire and is folded back in the width direction of the tire, so that the carcass layer (2a) is folded back in the width direction of the tire.
), (2b), and (2c) are overlapped. Furthermore, on the outside of the sudare kakagu (2), there is a weave other than the sudare weave, such as plain weave, satin weave, twill weave, mosiya weave, or karami weave, which is a feature of the present invention and is made of fibers made of the same material as the sudare. The fabric (8) is a sudare carcass (2b) (
2e) is arranged and buried in a biased manner adjacent to 2e). Since the tire according to the present invention is an open-sided tire, there is no breaker in the sidewall compared to the conventional breaker placed corresponding to the ground contact area of the tire, so if a cut occurs in the sidewall, it will not sag. While directly damaging the carcass and causing cut scratches to grow,
Since the woven fabric (8) other than the sudare weave is placed all over the outside of the sudare carcass (2), even if cut scratches occur on the sidewall, the threads of the diameter and weft of the fabric will interfere with each other, making it difficult for the cut scratches to grow. , and the resistance can also be greatly improved. A crescent-shaped tread rubber (6) with a predetermined thickness and a pattern on its surface is integrally laminated and adhered only to the tire contact surface. Fig. 2 is a view corresponding to Fig. 1 showing another embodiment of the bicycle tire according to the present invention, in which a fabric (8) other than the sudare weave is adjacent to only the sidewall portion outside the sudare carcass (2), forming a bias pattern. The other parts are exactly the same as those shown in FIG. 1, so the explanation will be omitted. Here, in order to help better understand the effects possessed by the tire according to the present invention, the following experimental examples will be explained. The tires used in each of the following experiments were tires manufactured according to the present invention (hereinafter referred to as
The tire of the present invention) and the conventional tire shown in FIG.
A bicycle tire with a width of 25 mm was used. (Experiment Example 1) Cut resistance experiments were conducted using the inventive product (1) and the conventional product (1).
A rubber substrate (11 °) was mounted on a rubber substrate (11
) and a steel heavy fi (14) of 50 mm/
Apply it to the side of the tire while descending at the speed of min.
The strength required to penetrate the side portion was measured, and the results shown in Table 1 were obtained. (Experiment Example 2) An experiment of anti-scratch property was carried out using the present invention product (1) and the conventional product (1).
) as shown in Figure 4, using a drum testing machine (15).
While the tire was rotated, an iron rod (16) with a diameter of 10IIInIφ and a rounded tip with a radius of 5II1111 was applied perpendicularly to the side part of the tire with a load of 0.5 kgf, and the time until the side part became punctured was measured. The results shown in Table 1 were obtained. The running conditions of this drum testing machine are a speed of 4 Qlua/h.
r, and the load was 60 kgf. (Experiment Example 3) Driving performance experiments were conducted using the inventive product (1) and the conventional product (1'
) tires were tested for cornering force (C, F) and rolling resistance (
R, R) were measured, and the results are also listed in Table 1. In this experiment, the camber angle of the cornering force was 20°, and the slip angle was 2a. Table 1 As is clear from the above experiments, it was confirmed that the product of the present invention greatly improved its puncture resistance while maintaining the conventional running performance. (Effects) As described above, the bicycle tire according to the present invention has a structure in which a fabric other than the sudare fabric is arranged and embedded in the bias direction on the outside of the sudare carcass layer of the open-side tire, thereby improving the cut resistance of the sidewall portion. Compared to conventional products of this type, it is approximately 1.6 times more cut resistant and approximately 1.8 times more scratch resistant, and is resistant to damage caused by puncture of the side parts by sharp debris on the road surface. , it effectively prevents accidents such as punctures, and maintains the performance of conventional products in rolling resistance, cornering force, etc., and has significantly improved the performance of open-side bicycle tires. .

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of an open-side tire in which the present invention is implemented, Fig. 2 is a cross-sectional view of a tire showing another embodiment of the present invention, and Fig. 3 is a cross-sectional view of a tire cut resistance test for puncture performance. FIG. 4 is a schematic explanatory diagram of a testing apparatus for testing tire puncture resistance against scratches;
FIG. 5 is a cross-sectional view of a conventional tire of this type. (1)... Bicycle tire (2) (2a) (2b) (2C)... Carcass (3)
... Bead part (6) ... Tread rubber (7) ... Breaker - (8) ... Patent applicant for textiles other than Stare weave Mitsuboshi Belting Co., Ltd. 1111 Figure 2 Figure 3 - m-]ノ. -Figure 4Figure 5Figure 17 and 7

Claims (1)

[Claims] 1. In an open-side tire in which a pair of bead portions are wrapped in a plurality of layers of carcass, and the carcass extends to the sidewall portion and tread portion of the tire, at least the sidewall is wrapped outside the carcass. A bicycle tire characterized in that a fabric other than a sudare fabric is arranged and buried in a bias direction in a portion thereof. 2. The fabric other than the sudare fabric is plain weave, satin weave, twill weave,
The bicycle tire according to claim 1, which is a fabric selected from the group of fabrics such as Moshiya weave and Karami weave.