JP2008179303A - Pneumatic tire for motorcycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a pneumatic tire for a motorcycle making durability at a high speed straight advancing time and grip at a high speed turning time compatible, more particularly realize the pneumatic tire capable of exerting proper durability and steering stability according to inputs when the inputs are different at each of straight advancing time and right and left cornering time. <P>SOLUTION: In this tire, a tread part 3 is made of a plurality of different rubber 11 to 13 adjacent in a tire width direction, and is divided into a center rubber region A in a center part including at least a tire equator part and both side parts rubber regions B1 and B2 in both side parts of the tire. JIS hardness of the rubber 11 composing the center rubber region A is higher than that of all the rubber 12 and 13 composing the both side parts rubber regions B1 and B2, and the JIS hardness of the rubber composing both the side parts rubber regions B1 and B2 are different in both the side parts of the tire. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pneumatic tire for a motorcycle (hereinafter, also simply referred to as “tire”), and more particularly to a pneumatic tire for a motorcycle having improved tread rubber characteristics on both sides of the tire.

  In recent years, the evolution of racing motorcycles has accelerated high output and high speed. Therefore, when traveling straight, heat generation at the center of the tire may be extremely high due to ultra-high speed running, and the tread rubber may be destroyed. To solve this problem, the durability of the tread rubber is improved. .

  On the other hand, it is necessary to obtain the grip necessary for high-speed turning during cornering, but when the rubber at the center of the tire with improved durability is placed on the entire tread surface as described above, sufficient grip cannot be exhibited. It was in.

  As a technique related to the improvement of motorcycle tires, for example, Patent Document 1 discloses that a tread portion has a tread width of 0.15 to 0. 0, which is a distance in the tire axial direction between one outer edge Q1, Q2. One shoulder region S from the boundary point P to one outer edge Q1 with reference to a boundary point P separating the distance 35 times from the tire equator C to one outer edge Q1, and the other from the boundary point P through the tire equator C And forming one shoulder region S and the remaining region O with different rubbers having a predetermined loss elastic modulus and loss compliance, respectively, so that the tire can be A technique for realizing a tire capable of improving the durability by equalizing the left and right wear amounts is disclosed.

Patent Document 2 also discloses that tread rubber extends from each tread edge to the tire equator CL side and joined at the joint surface for the purpose of improving running performance in accordance with the race circuit configuration. In this tread part, rubber bases with different compositions are used, and the joint width JW, which is the length along the tread surface between both ends in the tire axial direction of the joint surface, is the length along the tread surface between the tread edges. There is disclosed a motorcycle tire having an insertion ply that is smaller than the tread width TW and has a reinforcing cord along the joint surface.
JP-A-3-125604 (Claims etc.) JP-A-9-125604 (Claims etc.)

  As described above, in conventional pneumatic tires for motorcycles used for racing, etc., it is difficult to achieve both durability during high-speed straight travel and grip during high-speed turning. The establishment of was desired. In particular, in a racing course or the like in which the left and right inputs are different, it is more desirable that appropriate high-speed turning performance can be exhibited according to the left and right inputs.

  Accordingly, an object of the present invention is to solve the above problems by improving tread rubber, and to realize a pneumatic tire for a motorcycle that achieves both durability during high-speed straight traveling and grip during high-speed turning, In particular, the object is to realize a pneumatic tire for a motorcycle that can exhibit appropriate durability and steering stability in accordance with the input when the input is different between straight traveling and right and left cornering such as a race.

  As a result of diligent study, the present inventor has arranged the tread rubber at the center and both sides of the tire with appropriate characteristics to achieve both the durability at the time of high-speed straight traveling and the grip at the time of high-speed turning, in particular, The present invention has been completed by finding that a pneumatic tire for a motorcycle capable of exhibiting turning performance in accordance with left and right inputs can be obtained.

That is, a pneumatic tire for a motorcycle according to the present invention includes a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroid shape between the sidewall portions. For pneumatic tires
The tread portion is composed of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator portion, and both rubber regions on both sides of the tire,
The JIS hardness of the rubber constituting the center rubber region is higher than the JIS hardness of all the rubbers constituting the both side rubber regions, and the JIS hardness of the rubber constituting the both side rubber regions is It is characterized by being different.

Another pneumatic tire for a motorcycle of the present invention includes a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroidal shape between the sidewall portions. In pneumatic tires for motorcycles,
The tread portion is composed of a plurality of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator and rubber regions on both sides of the tire on both sides. One of the partial rubber regions is divided into an intermediate rubber adjacent to the center rubber region and an edge rubber disposed on the outside thereof.
The JIS hardness of the rubber constituting the center rubber region is higher than the JIS hardness of all the rubbers constituting the both side rubber regions, and the JIS hardness of the intermediate rubber and the both side rubber regions The rubber constituting the other has a different JIS hardness.

Furthermore, still another pneumatic tire for a motorcycle according to the present invention includes a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroidal shape between the sidewall portions. In the pneumatic tire for motorcycles provided,
The tread portion is composed of a plurality of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator and rubber regions on both sides of the tire on both sides. Both of the partial rubber regions are divided into an intermediate rubber adjacent to the center rubber region and an edge rubber disposed on the outside thereof.
The JIS hardness of the rubber constituting the center rubber region is higher than the JIS hardness of all the rubbers constituting the both side rubber regions, and the JIS hardness of the intermediate rubber is substantially the same on both sides of the tire. Or different from each other, and the JIS hardness of the edge rubber is different on both sides of the tire.

Furthermore, still another pneumatic tire for a motorcycle according to the present invention includes a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroid shape between the sidewall portions. In a pneumatic tire for a motorcycle comprising:
The tread portion is composed of a plurality of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator and rubber regions on both sides of the tire on both sides. Both of the partial rubber regions are divided into an intermediate rubber adjacent to the center rubber region and an edge rubber disposed on the outside thereof.
The rubber constituting the center rubber region has a JIS hardness higher than the JIS hardness of all the rubbers constituting the both side rubber regions, the JIS hardness of the intermediate rubber is different on both sides of the tire, and the edge The JIS hardness of the part rubber is substantially the same or different at both sides of the tire.

  In this invention, it is preferable that the area | region which the said intermediate part rubber occupies differs in a tire both sides. The tire of the present invention preferably has a directional pattern and a negative ratio in the range of 20% to 40%.

  According to the present invention, the above configuration makes it possible to realize a pneumatic tire for a motorcycle that achieves both durability during high-speed straight traveling and grip during high-speed turning, and in particular, straight traveling such as a race. Realizes a pneumatic tire for motorcycles that can exhibit the appropriate durability and handling stability according to the input even when the input is different at the time of cornering and left and right cornering, and can maximize the high-speed turning performance It became possible to do.

Hereinafter, preferred embodiments of the present invention will be described in detail.
FIG. 1 shows a cross-sectional view of a pneumatic tire 10 for a motorcycle according to a first embodiment of the present invention. The illustrated tire 10 includes a pair of bead portions 1, a pair of sidewall portions 2 connected to them, and a tread portion 3 connected in a toroidal shape between the sidewall portions 2.

  In the first embodiment of the present invention, as shown in the drawing, the tread portion 3 is constituted by a plurality of different rubbers 11 to 13 adjacent in the tire width direction, and at least a center rubber region in a central portion including the tire equator portion. A is divided into rubber regions B1 and B2 on both sides of the tire. Further, the JIS hardness of the rubber 11 constituting the center rubber region A is higher than the JIS hardness of all the rubbers 12 and 13 constituting the both side rubber regions B1 and B2, and constitutes the both side rubber regions B1 and B2. The JIS hardness of the rubbers 12 and 13 is different on both sides of the tire.

  By placing rubber 11 with high JIS hardness in the center rubber region A constituting the tire center portion of the tread rubber, and rubbers 12 and 13 with low JIS hardness in the rubber regions B1 and B2 on both sides, the vehicle goes straight. The high-speed durability at the time and the grip at the time of high-speed turning can be made compatible, and the JIS hardness of the rubbers 12 and 13 constituting the rubber regions B1 and B2 on both sides is made different on both sides of the tire. Therefore, it is possible to realize a pneumatic tire for a motorcycle that can appropriately set the left and right tread rubber characteristics and can exhibit better high-speed turning performance according to the left and right inputs.

  In the tire 10 shown in FIG. 1, the relationship of the JIS hardness of the rubber constituting each region is as follows: (JIS hardness of the rubber 11 in the center rubber region A)> (JIS hardness of the rubber 12 in both side rubber regions B1)> (JIS hardness of rubber 13 in both side rubber regions B2), and both side rubber regions B1 and B2 can be interchanged.

  FIG. 2 shows a sectional view of a pneumatic tire 20 for a motorcycle according to a second embodiment of the present invention. In the illustrated tire 20, the tread portion is divided into a center rubber region A at least including the tire equator portion, and both side rubber regions B 1 and B 2 on both sides of the tire. One B1 of B2 is divided | segmented into the intermediate part rubber | gum 22a adjacent to the center rubber area | region A, and the edge part rubber | gum 22b arrange | positioned on the outer side.

  In the second embodiment, the JIS hardness of the rubber 21 constituting the center rubber region A is higher than the JIS hardness of all the rubbers 22a, 22b, 23 constituting the both side rubber regions B1, B2, and The JIS hardness of the intermediate rubber 22a is different from the JIS hardness of the rubber 23 constituting the other B2 of the both side rubber regions B1 and B2. In this case, the JIS hardness of the edge rubber 22b is not particularly limited in relation to the intermediate rubber 22a and the rubber 23 constituting both side rubber regions B2.

  As a result, as in the case of the first embodiment, a rubber having a high JIS hardness is disposed in the center rubber region A, and a rubber having a low JIS hardness is disposed in the both side rubber regions B1 and B2, respectively. The high speed durability at the time and the grip at the time of high speed turning can be made compatible, and the JIS hardness of the intermediate rubber 22a and the JIS hardness of the rubber 23 constituting both side rubber regions B2 are different. Thus, it is possible to realize a pneumatic tire for a motorcycle that can appropriately set the left and right tread rubber characteristics and can exhibit better high-speed turning performance according to the left and right inputs.

  FIG. 3 shows a sectional view of a pneumatic tire 30 for a motorcycle according to a third embodiment of the present invention. In the illustrated tire 30, the tread portion is divided into a center rubber region A at least including the tire equator portion, and both side rubber regions B 1 and B 2 on both sides of the tire. Both B2 are divided | segmented into the intermediate part rubber | gum 32a, 33a adjacent to the center rubber area | region A, and the edge part rubber | gum 32b, 33b arrange | positioned on the outer side.

  In the third embodiment, the JIS hardness of the rubber 31 constituting the center rubber region A is higher than the JIS hardness of all the rubbers 32a, 33a, 32b, 33b constituting the both side rubber regions B1, B2. And (1) the JIS hardness of the intermediate rubbers 32a and 33a is substantially the same or different on both sides of the tire and the JIS hardness of the edge rubbers 32b and 33b is different on both sides of the tire, or (2) The JIS hardness of the intermediate rubbers 32a and 33a is different on both sides of the tire, and the JIS hardness of the edge rubbers 32b and 33b is substantially the same or different on both sides of the tire.

  As a result, as in the first and second embodiments, a rubber having a high JIS hardness is disposed in the center rubber region A, and a rubber having a low JIS hardness is disposed in the both side rubber regions B1 and B2. It is possible to achieve both high-speed durability during straight running and grip during high-speed turning, and at least the JIS hardness of either the middle rubber or the edge rubber is different on both sides of the tire. Therefore, it is possible to realize a pneumatic tire for a motorcycle that can appropriately set the left and right tread rubber characteristics and can exhibit better high-speed turning performance according to the left and right inputs.

  In the present invention, the ratio of the center rubber region A and the both side rubber regions B1 and B2 is not particularly limited, but in order to ensure high-speed durability when going straight, both side rubber regions B1 , B2 is preferably arranged at a ratio of 0.15 to 0.35 of the tread width so that the tires are not included in the region where the tire contacts the ground when the vehicle is traveling straight ahead. Further, the ratio of the intermediate rubber and the edge rubber in the both side rubber regions can be appropriately determined according to the desired tread rubber characteristics, and is not particularly limited. In the case where both of B2 are divided into the intermediate rubber and the edge rubber, the proportion of the intermediate rubber and the edge rubber may be different on both sides of the tire as shown in FIG. It may be the same (not shown).

  Variations of the divided structure of the tread rubber according to the present invention are shown in FIGS. In the case of (a) in the figure, both the rubber regions on both sides are divided into intermediate rubbers 42a and 43a and edge rubbers 42b and 43b, and the ratio of the intermediate rubber and the edge rubber is changed on both sides of the tire. The intermediate rubbers 42a and 43a have substantially the same JIS hardness, and the edge rubbers 42b and 43b have different JIS hardness. Also, (b) in the figure also divides both side rubber regions into intermediate rubbers 52a and 53a and edge rubbers 52b and 53b, and determines the ratio of the intermediate rubber and the edge rubber on both sides of the tire. In contrast to (a), the intermediate rubbers 42a and 43a have different JIS hardness, and the edge rubbers 42b and 43b have substantially the same JIS hardness.

  Further, (c) in the drawing is obtained by dividing only one of the both side rubber regions into an intermediate rubber and an edge rubber, and a rubber 62 and an intermediate rubber 63a constituting the both side rubber regions, Are different JIS hardnesses, and the rubber 62 and the edge rubber 63b constituting the both-side rubber regions have substantially the same JIS hardness, and (d) in FIG. This is a case where the rubber 72 and the edge rubber 73b constituting the part rubber region have different JIS hardnesses. Furthermore, (e) in the figure shows that the intermediate rubbers 82a and 83a have different JIS hardness, the edge rubbers 82b and 83b have substantially the same JIS hardness, and the regions occupied by the edge rubber are on both sides of the tire. (F) in the figure has a similar divided structure to that shown in (d), and the edge rubber 93b is laminated on the intermediate rubber 93a. In addition, it cannot be overemphasized that these division | segmentation structures can use all, changing right and left.

  As described above, the pneumatic tire for a motorcycle of the present invention can exhibit excellent high-speed turning performance according to left and right inputs, and in particular, a racing motorcycle used in a racing course with different left and right inputs. Etc. are preferably used. Therefore, the tire of the present invention can be suitably applied particularly to a tire having a directional pattern in which the mounting direction is specified, and more preferably in a racing tire having a negative ratio in the range of 20% to 40%. Useful.

  In the present invention, only the point that the tread rubber has the above-mentioned divided structure is important, and the details and materials of the tire structure other than that are not particularly limited. For example, although not illustrated, at least one carcass extending in a toroidal shape is disposed between the bead portions 1 via the sidewall portion 2 and the tread portion 3, and the crown portion of the carcass is radially outward. Is provided with at least one belt. In addition, a bead core is embedded in each bead portion 1, and both ends of the carcass are folded and locked around the bead core from the inside to the outside of the tire. Further, a tread pattern is appropriately formed on the surface of the tread portion 3, and an inner liner is formed in the innermost layer.

Hereinafter, the present invention will be described in more detail with reference to examples.
As shown in Table 1 below, the tread portion was divided into a center rubber region A and both side rubber regions B1 and B2, and each of the tires was made of a plurality of rubbers. The value of JIS hardness in the table is an index display in which the JIS hardness 55 of the rubber constituting the center rubber region A of Example 1 is 100, and the higher the value, the harder it is. The tire size was 190 / 65OR16.5, and a tread pattern (negative ratio: 35%) having directionality was formed on the surface of the tread portion.

  Each of the obtained test tires was mounted on a 1000 cc racing motorcycle, and the actual vehicle was evaluated on a circuit with a severe right input. The evaluation was performed on the four points of high-speed straight running stability, left and right cornering grips, and high-speed durability with the feeling of a professional rider, and was scored by a 10-point scale method. For any evaluation item, the higher the score, the higher the evaluation. The results are shown in Table 2 below.

  As shown in the results of Table 2 above, in the test tires of each example in which the tread rubber has a predetermined divided structure, compared to the conventional examples 1 and 2, high-speed straight running stability, left and right cornering grips, high-speed durability It was confirmed that high performance was obtained in a well-balanced manner for all sex evaluation items. Thus, according to the present invention, by appropriately using the tread rubber division pattern according to the input, the durability at the time of high-speed straight traveling and the grip at the time of high-speed turning can be made compatible even when the left and right inputs are different. It can be seen that a pneumatic tire for a motorcycle that can exhibit appropriate durability and steering stability according to the input can be obtained.

1 is a schematic cross-sectional view showing a pneumatic tire for a motorcycle according to a first embodiment of the present invention. It is a schematic sectional drawing which shows the pneumatic tire for motorcycles concerning the 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the pneumatic tire for motorcycles concerning the 3rd Embodiment of this invention. (A)-(f) is the schematic which shows the tread rubber of the pneumatic tire for motorcycles which concerns on suitable embodiment of this invention. 1 is a schematic cross-sectional view showing a pneumatic tire for a motorcycle according to Conventional Example 1. FIG. FIG. 7 is a schematic cross-sectional view showing a motorcycle pneumatic tire according to Conventional Example 2;

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bead part 2 Side wall part 3 Tread part 10, 20, 30 Motorcycle pneumatic tires 11, 21, 31, 41, 51, 61, 71, 81, 91 Rubber 12, 13, 23 which comprises a center rubber area | region , 62, 72, 92 Rubbers 22a, 32a, 33a, 42a, 43a, 52a, 53a, 63a, 73a, 82a, 83a, 93a constituting the rubber regions on both sides The intermediate rubbers 22b, 32b, 33b, 42b, 43b, 52b, 53b, 63b, 73b, 82b, 83b, 93b Edge rubber A Center rubber area B1, B2 Both side rubber areas

Claims (6)

In a pneumatic tire for a motorcycle including a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroidal shape between both sidewall portions,
The tread portion is composed of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator portion, and both rubber regions on both sides of the tire,
The JIS hardness of the rubber constituting the center rubber region is higher than the JIS hardness of all the rubbers constituting the both side rubber regions, and the JIS hardness of the rubber constituting the both side rubber regions is A pneumatic tire for motorcycles, characterized by being different in In a pneumatic tire for a motorcycle including a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroidal shape between both sidewall portions,
The tread portion is composed of a plurality of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator and rubber regions on both sides of the tire on both sides. One of the partial rubber regions is divided into an intermediate rubber adjacent to the center rubber region and an edge rubber disposed on the outside thereof.
The JIS hardness of the rubber constituting the center rubber region is higher than the JIS hardness of all the rubbers constituting the both side rubber regions, and the JIS hardness of the intermediate rubber and the both side rubber regions A pneumatic tire for a motorcycle, wherein the rubber constituting the other has a different JIS hardness. In a pneumatic tire for a motorcycle including a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroidal shape between both sidewall portions,
The tread portion is composed of a plurality of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator and rubber regions on both sides of the tire on both sides. Both of the partial rubber regions are divided into an intermediate rubber adjacent to the center rubber region and an edge rubber disposed on the outside thereof.
The JIS hardness of the rubber constituting the center rubber region is higher than the JIS hardness of all the rubbers constituting the both side rubber regions, and the JIS hardness of the intermediate rubber is substantially the same on both sides of the tire. A pneumatic tire for a motorcycle, wherein the edge portion rubber has different JIS hardness at both sides of the tire. In a pneumatic tire for a motorcycle including a pair of bead portions, a pair of sidewall portions that are continuous to the bead portions, and a tread portion that is continuous in a toroidal shape between both sidewall portions,
The tread portion is composed of a plurality of different rubbers adjacent to each other in the tire width direction, and is divided into a center rubber region at the center including at least the tire equator and rubber regions on both sides of the tire on both sides. Both of the partial rubber regions are divided into an intermediate rubber adjacent to the center rubber region and an edge rubber disposed on the outside thereof.
The rubber constituting the center rubber region has a JIS hardness higher than the JIS hardness of all the rubbers constituting the both side rubber regions, the JIS hardness of the intermediate rubber is different on both sides of the tire, and the edge A pneumatic tire for a motorcycle, characterized in that the JIS hardness of the part rubber is substantially the same or different at both sides of the tire.   The pneumatic tire for a motorcycle according to claim 3 or 4, wherein a region occupied by the intermediate rubber is different on both sides of the tire.   The pneumatic tire for a motorcycle according to any one of claims 1 to 5, having a directional pattern and having a negative ratio in a range of 20% to 40%.

Images