JP4369249B2 - Pneumatic tire for two-wheeled vehicle and mounting method thereof - Google Patents

Description

The present invention relates to a pneumatic tire for a motorcycle to be mounted on a motorcycle, and a method for mounting the pneumatic tire for a motorcycle, and in particular, a motocross mainly intended for traveling in a muddy area, and a pneumatic tire for a motorcycle for an enduro, and The present invention relates to a method for mounting a pneumatic tire for a motorcycle.

  For motorcycles traveling on rough terrain, for example, pneumatic tires for motorcycles having a block pattern as described in Patent Document 1 are used.

  Among the various characteristics of motorcycle terrain tires, the cornering grip of the rear tire is a very important characteristic.

Especially for racing tires used in motocross, enduro racing, etc., cornering grips during acceleration in muddy areas are particularly required, so the quality of the grip when driving the rear tire is an important factor. .
Japanese Patent Laid-Open No. 03-239605

  In conventional pneumatic tires for two-wheeled vehicles that place emphasis on the performance in muddy areas, the side perpendicular to the driving force direction (= rotation direction) is provided in the block to emphasize traction (driving force). It is difficult to obtain a high grip during cornering because the resultant force of the driving force is received at a corner portion with low rigidity (corner when viewed from above) in the block.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a pneumatic tire for a motorcycle that can greatly improve the cornering grip in a muddy area.

The invention according to claim 1 is a pneumatic tire for a motorcycle in which a block pattern is formed by providing a plurality of blocks on a tread, the tread having a center block disposed on a tire equator plane, A shoulder block disposed on the outside, an intermediate block disposed between the center block and the shoulder block, and when the tread is unfolded in a flat shape, the tire rotation on both sides of the tire equatorial plane A first inclined block row in which the shoulder block, the intermediate block, and the center block are arranged along a direction inclined with respect to the tire equatorial plane so that the shoulder block, the intermediate block, and the center block are sometimes grounded in order. And a step of each block constituting the first inclined block row is formed. The inclination angle of the first virtual inclination line that sequentially connects the center of gravity position of the tire from the shoulder block side to the center block side with respect to the tire equatorial plane is set within a range of 20 to 60 °, and constitutes the first inclination block row. The at least one intermediate block has an inclined side inclined within a range of 15 to 60 ° with respect to the tire circumferential direction on the tire rotation direction side and the tire equatorial plane side , and the tread is developed in a planar shape. When viewed, the intermediate block having the inclined side is arranged at least in the region of 20 to 80% of the tread half width from the tire equatorial plane to the shoulder side.

  Next, the operation of the pneumatic tire for a motorcycle according to claim 1 will be described.

  First, the first inclined block row consisting of the center block, intermediate block, and shoulder block is inclined so as to be grounded from the shoulder side, and the center of gravity of the tread surface of each block is sequentially connected from the shoulder block side to the center block side Since the inclination angle of the first virtual inclination line with respect to the tire equator plane is set within a range of 20 to 60 °, the resultant force of the cornering force and the driving force is the first inclination at the cornering in which the driving force is applied. Input from the direction intersecting the block row.

  During cornering, since the pneumatic tire for a motorcycle is inclined with respect to the road surface, the contact ratio of the intermediate block is larger than that of the center block and the shoulder block.

Since the inclined side provided in the intermediate block faces the input direction side of the resultant force, the intermediate block can easily receive the resultant force and the cornering grip during acceleration is improved. Here, the closer the inclined side is to the right angle with respect to the input direction of the resultant force, the better.

  If the intermediate block having the inclined side is not disposed in the region of 20 to 80% of the tread half-width from the tire equator surface to the shoulder side, improvement in cornering grip during acceleration cannot be expected.

  Further, when the angle of the inclined side is out of the range of 15 to 60 °, it is not possible to improve the cornering grip during acceleration.

  Furthermore, if the angle of the first virtual inclination line is out of the range of 20 to 60 °, the acceleration cornering grip cannot be improved as well.

  According to a second aspect of the present invention, in the pneumatic tire for a motorcycle according to the first aspect, an angle of the first virtual inclined line with respect to the tire equatorial plane gradually decreases from the tire equatorial plane side toward the shoulder side. It is characterized by that.

  Next, the operation of the pneumatic tire for a motorcycle according to claim 2 will be described.

  In a two-wheeled vehicle, cornering is performed by tilting the vehicle body, and the cornering force increases as the vehicle body is largely tilted. Therefore, the cornering force is greater on the shoulder side block than on the tire equator side.

  For this reason, since the angle of the resultant force of the cornering force and the driving force with respect to the tire equatorial plane increases toward the shoulder side, the row direction of the first inclined block row with respect to the resultant force is effective in receiving this resultant force. It is preferable that the angle of the first virtual inclined line with respect to the tire equatorial plane is gradually decreased from the tire equatorial plane side toward the shoulder so as to approach the right angle direction.

The invention according to claim 3 is a pneumatic tire for a motorcycle in which a block pattern is formed by providing a plurality of blocks on the tread, and when the tread is developed in a plane, the tire is on both sides of the tire equatorial plane. The center block, the intermediate block, and the shoulder block are arranged along a direction inclined with respect to the tire equatorial plane so that the center block, the intermediate block, and the shoulder block are grounded in this order when the tire rotates. Inclination angle with respect to the tire equator plane of the second imaginary inclined line that forms two inclined block rows and sequentially connects the center of gravity of the tread surface of each block constituting the second inclined block row from the center block side to the shoulder block side Is set within a range of 20 to 60 °, and the small number constituting the second inclined block row Kutomo one said intermediate block, the inclined side which is inclined in the range of 15 to 60 ° with respect to the tire circumferential direction, opposite direction and having the tire equatorial plane side to the tire rotation direction, the plane said tread The intermediate block having the inclined side when viewed in a shape is arranged in an area of 20 to 80% of the tread half-width at least from the tire equatorial plane to the shoulder side.

  Next, the operation of the pneumatic tire for a motorcycle according to claim 3 will be described.

  First, the 2nd inclination block row | line | column which consists of a center block, an intermediate | middle block, and a shoulder block is inclinedly arranged so that it may contact in the range of 20-60 degrees with respect to a tire equator surface and the tire equator surface side Therefore, at the time of cornering where the braking force is applied, the resultant force of the cornering force and the braking force is input from the direction intersecting the second inclined block row.

  During cornering, since the pneumatic tire for a motorcycle is inclined with respect to the road surface, the contact ratio of the intermediate block is larger than that of the center block and the shoulder block.

Since the inclined side provided in the intermediate block faces the input direction side of the resultant force, the intermediate block can easily receive the resultant force, and the cornering grip when the braking force is applied is improved. Here, the closer the inclined side is to the right angle with respect to the input direction of the resultant force, the better.

  If the intermediate block having the inclined side is not disposed in the region of 20 to 80% of the tread half width from the tire equator surface to the shoulder side, the cornering grip cannot be improved when the braking force is applied.

  Further, if the angle of the inclined side is out of the range of 15 to 60 °, the cornering grip cannot be improved when the braking force is applied.

  Further, when the angle of the first inclined block row is out of the range of 20 to 60 °, the cornering grip cannot be improved when the braking force is applied.

  According to a fourth aspect of the present invention, in the pneumatic tire for a motorcycle according to the third aspect, an angle of the second virtual inclined line with respect to the tire equatorial plane gradually decreases from the tire equatorial plane side toward the shoulder side. It is characterized by that.

  Next, the operation of the pneumatic tire for a motorcycle according to claim 4 will be described.

  In a two-wheeled vehicle, cornering is performed by tilting the vehicle body, and the cornering force increases as the vehicle body is largely tilted. Therefore, the cornering force is greater on the shoulder side block than on the tire equator side.

  For this reason, the angle of the resultant force of the cornering force and the braking force with respect to the tire equatorial plane increases toward the shoulder side. Therefore, in order to efficiently receive this resultant force, the row direction of the second inclined block row is relative to the resultant force. It is preferable that the angle of the second virtual inclined line with respect to the tire equatorial plane is gradually decreased from the tire equatorial plane side toward the shoulder so as to approach the right angle direction.

The invention according to claim 5 is a pneumatic tire for a motorcycle in which a block pattern is formed by providing a plurality of blocks on a tread, and when the tread is developed in a plane, the tire is on both sides of the tire equatorial plane. The shoulder block, the intermediate block, and the center block are arranged along a direction inclined with respect to the tire equatorial plane so that the shoulder block, the intermediate block, and the center block are grounded in this order when the tire rotates. 1 inclined block row is formed, the center block, the intermediate block, the intermediate block, along the direction inclined to the tire equatorial plane so as to come into contact with the center block, the intermediate block, and the shoulder block in this order during tire rotation, And a second inclined block row in which the shoulder blocks are arranged. The inclination angle with respect to the tire equatorial plane of the first virtual inclination line that sequentially connects the center of gravity of the tread surface of each block constituting the first inclined block row from the shoulder block side to the center block side is within a range of 20 to 60 °. A range in which the inclination angle of the second virtual inclination line, which is set and sequentially connects the center of gravity of the tread surface of each block constituting the second inclined block row from the center block side to the shoulder block side with respect to the tire equatorial plane, is 20 to 60 °. It is set within the at least one of said intermediate block first constitutes the inclined block row is inclined side of the tire rotation direction side and inclined in the range of 15 to 60 ° with respect to the tire circumferential direction have the tire equatorial plane side, at least one of the intermediate blocks constituting the second inclined block column 15 with respect to the tire circumferential direction The inclined sides inclined in the range of 0 ° opposite direction and having the tire equatorial plane side to the tire rotation direction, when viewed by expanding the tread in a plane, the intermediate block having the inclined edges , At least from the tire equatorial plane to the shoulder side, it is arranged in an area of 20 to 80% of the tread half width.

  Next, the operation of the pneumatic tire for a motorcycle according to claim 5 will be described.

The pneumatic tire for a motorcycle according to claim 5 includes two block rows, the first inclined block row described in claim 1 and the second inclined block row described in claim 2, and further includes a tire. the inclined sides inclined in the range of 15 to 60 ° to the circumferential direction, the tire rotational direction side and the tire equatorial plane side, and an intermediate block which has the opposite direction and the tire equatorial plane side to the tire rotation direction Therefore, the cornering grip during acceleration is improved and the cornering grip when the braking force is applied is improved.

  The invention according to claim 6 is the pneumatic tire for a motorcycle according to claim 5, wherein an angle of the first inclined block row with respect to a tire equatorial plane and an angle of the second inclined block row with respect to the tire equatorial plane are: Each is characterized by a gradual decrease from the tire equator side to the shoulder side.

  Next, the operation of the pneumatic tire for a motorcycle according to claim 6 will be described.

  Since the angle of the resultant force of the cornering force and the driving force with respect to the tire equatorial plane increases toward the shoulder side, the row direction of the first inclined block row is perpendicular to the resultant force in order to efficiently receive this resultant force. It is preferable that the angle with respect to the tire equatorial plane is gradually decreased from the tire equatorial plane side toward the shoulder side so as to approach.

  In addition, since the angle of the resultant force of the cornering force and the braking force with respect to the tire equatorial plane increases toward the shoulder side, in order to efficiently receive this resultant force, the row direction of the second inclined block row is relative to the resultant force. It is preferable that the angle with respect to the tire equatorial plane is gradually decreased from the tire equatorial plane side toward the shoulder side so as to approach the right angle direction.

  The method for mounting a pneumatic tire for a motorcycle according to claim 7 is characterized in that at least the pneumatic tire for motorcycle according to claim 1 or 2 is used as a rear wheel of the motorcycle.

  Since the pneumatic tire for a motorcycle according to claim 1 or claim 2 has an excellent cornering grip during acceleration, the pneumatic tire for a motorcycle can be used as a driving wheel of a motorcycle on which a driving force acts, that is, a rear wheel of the motorcycle. Improved cornering performance during acceleration.

  The method for mounting a pneumatic tire for a motorcycle according to claim 8 is characterized in that at least the pneumatic tire for motorcycle according to claim 3 or 4 is used for a front wheel of the motorcycle.

  Since the pneumatic tire for a motorcycle according to claim 3 or claim 4 has an excellent cornering grip when a braking force is applied, the pneumatic tire is used for a front wheel of a motorcycle in which a large braking force is applied in comparison with the rear wheel. The cornering performance of a two-wheeled vehicle when braking force is applied is improved.

  The method for mounting a pneumatic tire for a motorcycle according to claim 9 uses the pneumatic tire for a motorcycle according to claim 1 or 2 as a rear wheel of the motorcycle, and the motorcycle according to claim 3 or 4. It is characterized by using pneumatic tires for the front wheels.

  The pneumatic tire for a motorcycle according to claim 1 or 2 having excellent cornering grip at the time of acceleration is used for a rear wheel of the motorcycle, and the pneumatic tire for motorcycle having excellent cornering grip when a braking force is applied. By using the front wheel, the cornering performance of the motorcycle is improved when accelerating and when braking force is applied.

  As described above, since the pneumatic tire for a motorcycle according to claim 1 has the above configuration, it has an excellent effect that the cornering performance during acceleration of the mounted motorcycle can be improved.

  Since the pneumatic tire for a motorcycle according to claim 2 has the above-described configuration, it has an excellent effect that the cornering performance during acceleration can be improved regardless of the size of the cornering force.

  Since the pneumatic tire for a motorcycle according to claim 3 has the above-described configuration, it has an excellent effect of improving cornering performance when the braking force of the mounted motorcycle is applied.

  Since the pneumatic tire for a motorcycle according to claim 4 has the above-described configuration, it has an excellent effect that the cornering performance when a braking force is applied can be improved regardless of the size of the cornering force.

  Since the pneumatic tire for a motorcycle according to claim 5 has the above-described configuration, it has an excellent effect of improving the cornering performance at the time of acceleration and the cornering performance when a braking force is applied to the mounted motorcycle.

  Since the pneumatic tire for a motorcycle according to claim 6 has the above-described configuration, the cornering performance at the time of acceleration and the cornering performance when a braking force is applied can be improved regardless of the size of the cornering force. Has an effect.

  According to the method for mounting a pneumatic tire for a motorcycle according to claim 7, the cornering performance during acceleration of the motorcycle can be improved.

  According to the method for mounting a pneumatic tire for a motorcycle according to claim 8, the cornering performance when the braking force of the motorcycle is applied can be improved.

  According to the method for mounting a pneumatic tire for a motorcycle according to claim 9, there is an excellent effect that the cornering performance of the motorcycle can be improved during acceleration and when a braking force is applied.

[First Embodiment]
A pneumatic tire for a motorcycle according to a first embodiment of the present invention will be described with reference to FIG.

  FIG. 1 is a plan view of a tread 12 of a pneumatic tire 10 for a motorcycle according to the present embodiment as seen in a flat shape.

  As shown in FIG. 1, on the tire equatorial plane CL of the tread 12, a plurality of center blocks 14 are spaced in the tire circumferential direction (arrow A direction (tire rotation direction) and direction opposite to the arrow A direction). Are arranged.

  A plurality of first intermediate blocks 18 are arranged at intervals in the tire circumferential direction on the outer side in the tire width direction of the center block 14.

  A plurality of second intermediate blocks 20 are arranged at intervals in the tire circumferential direction on the outer side in the tire width direction of the first intermediate block 18.

  A plurality of shoulder blocks 22 are arranged at intervals in the tire circumferential direction on the outer side in the tire width direction of the second intermediate block 20.

  On both sides of the tire equatorial plane CL, along the direction inclined with respect to the tire equatorial plane CL so that the shoulder block 22, the second intermediate block 20, the first intermediate block 18, and the center block 14 are grounded in this order when the tire rotates. A first inclined block row 24 in which the shoulder block 22, the second intermediate block 20, the first intermediate block 18, and the center block 14 are sequentially arranged is formed (as shown by a two-dot chain line in FIG. 1) A block string is a combination of close blocks of different types.)

  In addition, the center block 14 of this embodiment is exhibiting the substantially rectangular shape long in the tire width direction which consists of two sides extended along a tire circumferential direction, and two sides extended along a tire width direction. A narrow groove 16 extending in the circumferential direction is formed in the middle portion of the center block 14 in the tire width direction.

  The first intermediate block 18 constituting the first inclined block row 24 has a pair of two sides extending in the tire circumferential direction, a pair of two sides extending in the tire width direction, and a range of 15 to 60 ° with respect to the tire circumferential direction. And a pentagon having a total of five inclined sides 18A inclined in the same direction as the first inclined block row 24, and the inclined sides 18A are provided on the tire rotation direction side.

  Similarly, the second intermediate block 20 constituting the first inclined block row 24 has a pair of two sides extending in the tire circumferential direction, a pair of two sides extending in the tire width direction, and 15 to 60 with respect to the tire circumferential direction. A pentagon consisting of a total of 5 sides of the inclined side 20A inclined in the same direction as the first inclined block row 24 within the range of ° is provided, and the inclined side 20A is provided on the tire rotation direction side.

  The first intermediate block 18 having the inclined side 18A and the second intermediate block 20 having the inclined side 20A have at least a tread half width W / 2 from the tire equatorial plane CL to the shoulder side (tread from the tire equatorial plane CL to the tread end 12E). The dimension measured along the surface (see FIGS. 1 and 2)) is preferably arranged in an area of 20 to 80%.

  Here, the inclination angle θa with respect to the tire equator plane CL of the first virtual inclination line FLA that sequentially connects the gravity center position G of the tread surface of each block constituting the first inclination block row 24 from the shoulder block 22 side to the center block 14 side is It is preferable to set within a range of 20 to 60 °.

  Further, it is more preferable that the inclination angle θa gradually decreases from the tire equatorial plane CL side toward the shoulder side, and the angle difference between the inclination angle θa on the tire equatorial plane CL side and the inclination angle θa on the shoulder side is 5-20. Within the range of ° is preferable.

  The first intermediate block 18 having the inclined side 18A and the second intermediate block 20 having the inclined side 20A are at least 20 to 80% of the tread half width W / 2 along the tread surface from the tire equatorial plane CL to the shoulder side. It is preferable to arrange in (refer FIG. 2).

The angle θ _18A of the inclined side 18A of the first intermediate block 18 with respect to the tire circumferential direction is preferably within a range of 35 to 60 °.

The angle θ _20A of the inclined side 20A of the second intermediate block 20 with respect to the tire circumferential direction is preferably within a range of 15 to 45 °.

In addition, the negative ratio of the tread 12 is preferably in the range of 65 to 97%.
(Function)
In the pneumatic tire 10 for a motorcycle according to the present embodiment, the first inclined block row 24 including the center block 14, the first intermediate block 18, the second intermediate block 20, and the shoulder block 22 has a tire equatorial plane CL. Since it is inclined and arranged so as to be grounded from the shoulder side within a range of 20 to 60 °, the resultant force of the cornering force CF and the driving force TF during cornering (for example, right turn) where the driving force is applied. The MFA is input from the tire equatorial plane CL side and from the intersecting direction with respect to the first inclined block row 24 on the right side.

  Since the two-wheeled pneumatic tire 10 is inclined with respect to the road surface during cornering, the contact ratio of the first intermediate block 18 and the second intermediate block 20 is larger than that of the center block 14.

Since the inclined side 18A provided in the first intermediate block 18 and the inclined side 20A provided in the second intermediate block 20 face the input direction side of the resultant force MFA, the first intermediate block 18 and the second intermediate block 20 easily receives the resultant force MFA, and the cornering grip at the time of acceleration is improved.

  In addition, the cornering force increases as the vehicle body is tilted greatly.

  For this reason, the angle of the resultant force MFA of the cornering force CF and the driving force TF with respect to the tire equatorial plane CL becomes larger toward the shoulder side.

  Therefore, in order to efficiently receive this resultant force MFA, the inclination angle of the first virtual inclination line FLA with respect to the tire equatorial plane CL as in this embodiment so that the first virtual inclination line FLA approaches a right angle with respect to the resultant force MFA. It is preferable to gradually reduce θa from the tire equatorial plane CL side toward the shoulder side.

  Further, it is preferable that the inclined side 18A provided in the first intermediate block 18 to which the resultant force MFA is actually input and the inclined side 20A provided in the second intermediate block 20 are also inclined in the same manner as the first virtual inclined line FLA. As a result, the input direction of the resultant force MFA can be brought close to a right angle with respect to the inclined side 18A and the inclined side 20A.

  As a result, the cornering performance during acceleration can be improved regardless of the size of the cornering force.

  Here, if the first intermediate block 18 and the second intermediate block 20 are not arranged in the region of 20 to 80% of the tread half width W / 2 from the tire equatorial plane CL to the shoulder side, the cornering performance during acceleration is improved. I can't hope.

If the angle theta _18A inclined side 18A provided in the first intermediate block 18 is outside the range of 35 to 60 °, it can not be expected similarly improved acceleration when cornering performance.

If the angle theta _20A inclined side 20A provided in the second intermediate block 20 is outside the range of 15 to 45 °, it can not be expected similarly improved acceleration when cornering performance.

  In addition, when the angle θa of the first inclined block row 24 is out of the range of 20 to 60 °, improvement in cornering performance during acceleration cannot be expected.

In addition, although it is preferable to mount the pneumatic tire 10 for a motorcycle of this embodiment on a driving wheel (rear wheel), it may be mounted on a front wheel.
[Second Embodiment]
A pneumatic tire for a motorcycle according to a second embodiment of the present invention will be described with reference to FIG.

  FIG. 3 is a plan view of the tread 112 of the pneumatic tire 110 for a motorcycle according to the present embodiment as seen in a flat shape.

  As shown in FIG. 3, on the tire equatorial plane CL of the tread 112, a plurality of center blocks 114 are spaced in the tire circumferential direction (arrow A direction (tire rotation direction) and direction opposite to the arrow A direction). Are arranged.

  On the outer side in the tire width direction of the center block 114, a plurality of first intermediate blocks 118 are arranged at intervals in the tire circumferential direction.

  On the outer side in the tire width direction of the first intermediate block 118, a plurality of second intermediate blocks 120 are arranged at intervals in the tire circumferential direction.

  On the outer side in the tire width direction of the second intermediate block 120, a plurality of shoulder blocks 122 are arranged at intervals in the tire circumferential direction.

  On both sides of the tire equatorial plane CL, along the direction inclined with respect to the tire equatorial plane CL so that the center block 114, the first intermediate block 118, the second intermediate block 120, and the shoulder block 122 are grounded in this order when the tire rotates. A second inclined block row 124 in which the center block 114, the first intermediate block 118, the second intermediate block 120, and the shoulder block 122 are sequentially arranged is formed (note that the nearest different blocks are connected to form a block row) Yes.)

  In addition, the center block 114 of the present embodiment has a long rectangle in the tire width direction including two sides extending along the tire circumferential direction and two sides extending along the tire width direction. A narrow groove 116 extending in the circumferential direction is formed in the middle portion of the center block 114 in the tire width direction.

The first intermediate block 118 constituting the second inclined block row 124 includes a pair of two sides extending in the tire circumferential direction, a pair of two sides extending in the tire width direction, and a range of 15 to 60 ° with respect to the tire circumferential direction. In the same direction as the second inclined block row 124 and a pentagon having a total of five sides, and the inclined side 118B is on the side opposite to the tire rotation direction and on the tire equatorial plane side . I have.

Similarly, the second intermediate block 120 constituting the second inclined block row 124 has a pair of two sides extending in the tire circumferential direction, a pair of two sides extending in the tire width direction, and 15 to 60 with respect to the tire circumferential direction. Is a pentagon consisting of a total of five sides of the inclined side 120B inclined in the same direction as the second inclined block row 124, and the inclined side 120B is on the side opposite to the tire rotation direction and on the tire equator. It is provided on the surface side .

  The first intermediate block 118 having the inclined side 118B and the second intermediate block 120 having the inclined side 120B are arranged at least in the region of 20 to 80% of the tread half width W / 2 from the tire equatorial plane CL to the shoulder side. Is preferred.

  Here, the inclination angle θb with respect to the tire equatorial plane CL of the second virtual inclination line FLB that sequentially connects the center of gravity G of the tread surface of each block constituting the second inclined block row 124 from the center block 114 side to the shoulder block 122 side is It is preferable to set within a range of 20 to 60 °.

  Further, it is more preferable that the inclination angle θb gradually decreases from the tire equatorial plane CL side toward the shoulder side, and the angle difference between the inclination angle θb on the tire equatorial plane CL side and the inclination angle θb on the shoulder side is 5 to 20. Within the range of ° is preferable.

  The first intermediate block 118 having the inclined side 118B and the second intermediate block 120 having the inclined side 120B are at least 20 to 80% of the tread half width W / 2 along the tread surface from the tire equatorial plane CL to the shoulder side. It is preferable to arrange in.

The angle θ _118B of the inclined side 118B of the first intermediate block 118 with respect to the tire circumferential direction is preferably in the range of 35 to 60 °.

The angle θ _120B of the inclined side 120B of the second intermediate block 120 with respect to the tire circumferential direction is preferably in the range of 15 to 45 °.

The negative ratio of the tread 112 is preferably in the range of 65 to 97%.
(Function)
In the pneumatic tire 110 for a motorcycle according to the present embodiment, the second inclined block row 124 including the center block 114, the first intermediate block 118, the second intermediate block 120, and the shoulder block 122 has a tire equatorial plane CL. In the range of 20 to 60 ° and inclined so as to come into contact with the tire equatorial plane CL, the cornering force CF and the braking force BF are applied during cornering (for example, right turn) where the braking force is applied. Is input from the tire equatorial plane CL side and from the intersecting direction with respect to the second inclined block row 124 on the right side.

  During cornering, the pneumatic tire 110 for a motorcycle is inclined with respect to the road surface, so that the ground contact ratio of the first intermediate block 118 and the second intermediate block 120 is larger than that of the center block 114.

Since the inclined side 118B provided in the first intermediate block 118 and the inclined side 120B provided in the second intermediate block 120 face the input direction side of the resultant force MFB, the first intermediate block 118 and the second intermediate block 120 becomes easy to receive the resultant force MFB, and the cornering grip when the braking force is applied is improved.

  In addition, the cornering force increases as the vehicle body is tilted greatly.

  For this reason, the angle of the resultant force MFB of the cornering force CF and the braking force BF with respect to the tire equatorial plane CL becomes larger toward the shoulder side.

  Therefore, in order to efficiently receive the resultant force MFB, the inclination angle of the second virtual inclination line FLB with respect to the tire equatorial plane CL as in the present embodiment so that the second virtual inclination line FLB approaches a right angle with respect to the resultant force MFB. It is preferable to gradually reduce θb from the tire equatorial plane CL side toward the shoulder side.

  Further, it is preferable that the inclined side 118B provided in the first intermediate block 118 to which the resultant force MFB is actually input and the inclined side 120B provided in the second intermediate block 120 are also inclined in the same manner as the second virtual inclined line FLB. As a result, the input direction of the resultant force MFB can be made closer to a right angle with respect to the inclined side 118B and the inclined side 120B.

  Thereby, the cornering performance when the braking force is applied can be improved regardless of the size of the cornering force.

  Here, if the first intermediate block 118 and the second intermediate block 120 are not arranged in the region of 20 to 80% of the tread half width W / 2 from the tire equatorial plane CL to the shoulder side, the braking force is applied. Cannot improve cornering performance.

If the angle theta _118B inclined side 118B provided on the first intermediate block 118 is out of the range of 35 to 60 °, it can not be expected to improve the cornering performance at the time of action of the same braking force.

If the angle theta _120B inclined side 120B provided in the second intermediate block 120 is out of the range of 15 to 45 °, it can not be expected to improve the cornering performance at the time of action of the same braking force.

  In addition, when the angle θb of the second inclined block row 124 is out of the range of 20 to 60 °, the cornering performance cannot be improved when the braking force is applied.

The pneumatic tire 110 for a motorcycle according to the present embodiment is preferably mounted on the front wheel, but may be mounted on the rear wheel.
[Third Embodiment]
A pneumatic tire for a motorcycle according to a third embodiment of the present invention will be described with reference to FIG.

  FIG. 4 is a plan view of the tread 212 of the pneumatic tire 210 for a motorcycle according to the present embodiment as seen in a flat shape.

  As shown in FIG. 4, on the tire equator plane CL of the tread 212, a plurality of center blocks 214 are arranged at intervals in the tire circumferential direction.

  A plurality of first intermediate blocks 218 are arranged at intervals in the tire circumferential direction on the outer side in the tire width direction of the center block 214.

  On the outer side in the tire width direction of the first intermediate block 218, the second intermediate block 221 and the second intermediate block 223 are alternately arranged at intervals in the tire circumferential direction.

  A plurality of shoulder blocks 222 are arranged at intervals in the tire circumferential direction outside the second intermediate block 221 and the second intermediate block 223 in the tire width direction.

  On both sides of the tire equatorial plane CL, along the direction inclined with respect to the tire equatorial plane CL so that the shoulder block 222, the second intermediate block 221, the first intermediate block 218, and the center block 214 are grounded in this order when the tire rotates. A first inclined block row 224A is formed in which a shoulder block 222, a second intermediate block 221, a first intermediate block 218, and a center block 214 are sequentially arranged.

  Here, the inclination angle θa with respect to the tire equator plane CL of the first virtual inclination line FLA that sequentially connects the gravity center position G of the tread surface of each block constituting the first inclination block row 224A from the shoulder block 222 side to the center block 214 side is The inclination angle θa is preferably set within a range of 20 to 60 °, and more preferably gradually decreased from the tire equatorial plane CL side toward the shoulder side.

The first intermediate block 218 includes an inclined side 218A that is inclined in the same direction as the first inclined block row 224A on the tire rotation direction side and the tire equatorial plane side within a range of 15 to 60 ° with respect to the tire circumferential direction. In addition, an inclined side 218B that is inclined in the same direction as the second inclined block row 224B within a range of 15 to 60 ° with respect to the tire circumferential direction is provided on the side opposite to the tire rotation direction and on the tire equatorial plane side . .

  Note that the first intermediate block 218 of the present embodiment constitutes the first inclined block row 224A and also constitutes the second inclined block row 224B.

The second intermediate block 221 constituting the first inclined block row 224A has an inclined side 221A inclined within the range of 15 to 60 ° with respect to the tire circumferential direction and in the same direction as the first inclined block row 224A. It is provided on the tire rotation direction side and the tire equatorial plane side .

The second intermediate block 223 constituting the second inclined block row 224B has an inclined side 223B that is inclined in the same direction as the second inclined block row 224B within a range of 15 to 60 ° with respect to the tire circumferential direction. It is provided on the side opposite to the tire rotation direction and on the tire equatorial plane .

  Here, the first intermediate block 218 having the inclined side 218A and the inclined side 218B, the second intermediate block 221 having the inclined side 221A, and the second intermediate block 223 having the inclined side 223B are at least shouldered from the tire equatorial plane CL. It is preferable to arrange in the region of 20 to 80% of the tread half width W / 2 to the side.

The angle θ _218A of the inclined side 218A of the first intermediate block 218 with respect to the tire circumferential direction is preferably in the range of 35 to 60 °.

The angle θ _{218B with} respect to the tire circumferential direction of the inclined side 218B of the first intermediate block 218 is preferably in the range of 35 to 60 °.

An angle θ _221A of the inclined side 221A of the second intermediate block 221 with respect to the tire circumferential direction is preferably within a range of 15 to 45 °.

The angle θ _223B of the inclined side 223B of the second intermediate block 223 with respect to the tire circumferential direction is preferably within a range of 15 to 45 °.

Note that the negative ratio of the tread 212 is preferably in the range of 65 to 97%.
(Function)
In the pneumatic tire 210 for a motorcycle according to the present embodiment, when cornering (for example, turning right) in which driving force is applied, the resultant force MFA of the cornering force CF and the driving force TF is the right first inclined block row 224A. In contrast, the input is made from the tire equatorial plane CL side and from the intersecting direction.

In addition, since the inclined side 218A provided in the first intermediate block 218 and the inclined side 221A provided in the second intermediate block 221 are directed to the input direction side of the resultant force MFA, the first intermediate block 218 and the second intermediate block 218 are provided. The intermediate block 221 can easily receive the resultant force MFA, and the cornering grip during acceleration is improved.

  Also in this embodiment, the inclination angle θa of the first virtual inclination line FLA with respect to the tire equator plane CL is gradually decreased from the tire equator plane CL side toward the shoulder side, and the inclined side 218A and the inclined side 221A are Since it is inclined according to one virtual inclined line FLA, the cornering performance during acceleration can be improved regardless of the size of the cornering force.

  If the first intermediate block 218 and the second intermediate block 221 are not disposed within the region of 20 to 80% of the tread half width W / 2 from the tire equatorial plane CL to the shoulder side, it is possible to improve cornering performance during acceleration. Absent.

If the angle theta _218A inclined side 218A provided in the first intermediate block 218 is out of the range of 35 to 60 °, it can not be expected similarly improved acceleration when cornering performance.

If the angle theta _221A inclined side 221A provided in the second intermediate block 221 is out of the range of 15 to 45 °, it can not be expected similarly improved acceleration when cornering performance.

  Further, if the angle θa of the first inclined block row 224A is out of the range of 20 to 60 °, improvement in cornering performance during acceleration cannot be expected.

  Next, during cornering where the braking force is applied (for example, turning right), the resultant force MFB of the cornering force CF and the braking force BF is from the tire equatorial plane CL side with respect to the second inclined block row 224B on the right side. And it inputs from the direction which crosses.

Further, since the inclined side 218B provided in the first intermediate block 218 and the inclined side 223B provided in the second intermediate block 223 are directed to the input direction side of the resultant force MFB, the first intermediate block 218 and the second intermediate block 218 are provided. The intermediate block 223 can easily receive the resultant force MFB, and the cornering grip when the braking force is applied is improved.

  Further, the inclination angle θb of the second virtual inclination line FLB with respect to the tire equatorial plane CL is gradually decreased from the tire equatorial plane CL side toward the shoulder side, and the inclined side 218B and the inclined side 223B are changed to the second virtual inclination line FLB. Since it is also inclined, the cornering performance when the braking force is applied can be improved regardless of the size of the cornering force.

  If the first intermediate block 218 and the second intermediate block 223 are not arranged in the region of 20 to 80% of the tread half width W / 2 from the tire equatorial plane CL to the shoulder side, cornering when the braking force is applied Improve performance.

If the angle theta _218B inclined side 218B provided on the first intermediate block 218 is out of the range of 35 to 60 °, it can not be expected to improve the cornering performance at the time of action of the same braking force.

If the angle theta _223B inclined side 223B provided in the second intermediate block 223 is out of the range of 15 to 45 °, it can not be expected to improve the cornering performance at the time of action of the same braking force.

When the angle θ _218A of the inclined side 218A of the first intermediate block 218 is out of the range of 35 to 60 °, improvement in cornering performance during acceleration cannot be expected.

If the angle θ _221A of the inclined side 221A of the second intermediate block 221 is out of the range of 15 to 45 °, the acceleration cornering performance cannot be expected to be improved.

  In addition, when the angle θb of the second inclined block row 224B is out of the range of 20 to 60 °, the cornering performance cannot be improved when the braking force is applied.

  By the way, in actual cornering operations, it is sometimes necessary to loosen the accelerator according to the curved shape of the corner. At this time, the braking force may act on the tire instantaneously.

  Therefore, like the pneumatic tire 210 for a motorcycle according to the present embodiment, by having the first inclined block row 224A and the second inclined block row 224B, it is further stable at the time of cornering where braking force acts on the way. A cornering grip is obtained.

  In addition, it is preferable to install the pneumatic tire 210 for a motorcycle according to the present embodiment simultaneously with the front and rear wheels.

  In the above embodiment, two rows of intermediate blocks are arranged between the center block and the shoulder block. However, the present invention is not limited to this, and at least one row of intermediate blocks is provided between the center block and the shoulder block. As long as the intermediate blocks are arranged, three or more rows of intermediate blocks may be arranged.

  The shape of the intermediate block may be a pentagon or more polygon.

In order to receive the resultant force in the intermediate block, the length of the inclined side is required to some extent. The length of the inclined side is preferably 8% or more, more preferably 15% or more of the circumferential length of the intermediate block while leaving the side extending in the tire circumferential direction and the side extending in the tire width direction.
(Test example)
In order to confirm the effect of the present invention, one type of conventional tire and three types of tires according to the embodiments of the present invention were prepared and mounted on an actual vehicle to grip corner acceleration and corner grip deceleration on mud roads. And a comparison of handling.

  The test was performed by running a motorcycle equipped with test tires on a muddy road.

The evaluation is a feeling evaluation (maximum 10 points) by a test rider, and the larger the value, the better the performance.
Example 1: Tire according to the first embodiment Example 2: Tire according to the second embodiment Example 3: Tire according to the third embodiment Conventional example: A tire having a tread pattern shown in FIG. As shown in FIG. 5, the center blocks 300 and 302, the intermediate block 304, and the shoulder block 306 are provided, but each block is a quadrangle and does not have an inclined side. The negative ratio is set to be equivalent to that in the example.
Rear tire size: 140 / 80-18
Front tire size: 90 / 90-21

試験の結果、本発明の適用された実施例のタイヤを装着した二輪車は、コーナリング時のグリップが向上していることが分かる。

As a result of the test, it can be seen that the two-wheeled vehicle equipped with the tire of the example to which the present invention is applied has improved grip during cornering.

1 is a development view of a tread of a pneumatic tire for a motorcycle according to a first embodiment. 1 is a cross-sectional view of a pneumatic tire for a motorcycle according to a first embodiment. FIG. 6 is a development view of a tread of a pneumatic tire for a motorcycle according to a second embodiment. It is an expanded view of the tread of the pneumatic tire for motorcycles concerning a 3rd embodiment. FIG. 6 is a development view of a tread of a pneumatic tire for a motorcycle according to a conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pneumatic tire for two-wheeled vehicles 12 Tread 14 Center block 18A Inclined side 18 Intermediate block 20A Inclined side 20 Intermediate block 22 Shoulder block 24 Inclined block row 110 Two-wheeled pneumatic tire 112 Tread 114 Center block 118B Inclined side 118 Intermediate block 120B Inclined side 120A inclined side 120 intermediate block 122 shoulder block 124 inclined block row 210 tire 212 tread 214 center block 218A inclined side 218B inclined side 218 intermediate block 221A inclined side 221 intermediate block 222 shoulder block 223B inclined side 223 intermediate block 224A inclined block row 224B inclined Block row 300 Center block 304 Intermediate block 306 Shoulder Block CL tire equatorial plane FLA imaginary inclined line FLB imaginary inclined line G gravity position W / 2 tread half width

Claims (9)

A pneumatic tire for a motorcycle in which a block pattern is formed by providing a plurality of blocks on a tread,
The tread includes a center block disposed on the tire equatorial plane, a shoulder block disposed on the outermost side in the tire width direction, and an intermediate block disposed between the center block and the shoulder block,
When the tread is viewed in a flat shape, the shoulder block, the intermediate block, and the center block are inclined to the tire equatorial plane in order of grounding in order of the shoulder block, the intermediate block, and the center block when the tire rotates. A first inclined block row in which the shoulder block, the intermediate block, and the center block are arranged along the center block, and the center of gravity position of the tread of each block constituting the first inclined block row is defined from the shoulder block side. The inclination angle of the first virtual inclination line sequentially connected to the center block side with respect to the tire equatorial plane is set within a range of 20 to 60 °,
At least one of the intermediate blocks constituting the first inclined block row has an inclined side that is inclined within a range of 15 to 60 ° with respect to the tire circumferential direction on the tire rotation direction side and the tire equatorial plane side . And
When the tread is developed in a planar shape, the intermediate block having the inclined side is disposed within a region of 20 to 80% of the tread half width from at least the tire equatorial plane to the shoulder side.
This is a pneumatic tire for motorcycles.   2. The pneumatic tire for a motorcycle according to claim 1, wherein an angle of the first virtual inclined line with respect to a tire equator plane gradually decreases from a tire equator plane side toward a shoulder side. A pneumatic tire for a motorcycle in which a block pattern is formed by providing a plurality of blocks on a tread, and when the tread is unfolded in a planar shape, the center block when the tire rotates, A second inclined block row is formed in which the center block, the intermediate block, and the shoulder block are arranged along a direction inclined with respect to the tire equatorial plane so as to contact the intermediate block and the shoulder block in this order. The inclination angle with respect to the tire equatorial plane of the second virtual inclination line that sequentially connects the center of gravity of the tread surface of each block constituting the second inclined block row from the center block side to the shoulder block side is within a range of 20 to 60 °. Is set,
At least one of the intermediate blocks constituting the second inclined block row has an inclined side inclined within a range of 15 to 60 ° with respect to the tire circumferential direction, on the side opposite to the tire rotation direction and on the tire equator. On the face side ,
When the tread is developed in a planar shape, the intermediate block having the inclined side is disposed within a region of 20 to 80% of the tread half width from at least the tire equatorial plane to the shoulder side.
This is a pneumatic tire for motorcycles.   4. The pneumatic tire for a motorcycle according to claim 3, wherein an angle of the second virtual inclined line with respect to the tire equatorial plane gradually decreases from the tire equatorial plane side toward the shoulder side. A pneumatic tire for a motorcycle in which a block pattern is formed by providing a plurality of blocks on a tread,
When the tread is viewed in a flat shape, the shoulder block, the intermediate block, and the center block are inclined to the tire equatorial plane in order of grounding in order of the shoulder block, the intermediate block, and the center block when the tire rotates. A first inclined block row in which the shoulder block, the intermediate block, and the center block are arranged along the tire block, and the center block, the intermediate block, and the shoulder block are grounded in this order when the tire rotates. A second inclined block row in which the center block, the intermediate block, and the shoulder block are arranged along a direction inclined with respect to the equator plane is formed,
The inclination angle of the first virtual inclination line connecting the center of gravity of the tread surface of each block constituting the first inclined block row sequentially from the shoulder block side to the center block side with respect to the tire equatorial plane is set within a range of 20 to 60 °. And
The inclination angle with respect to the tire equatorial plane of the second virtual inclination line that sequentially connects the center of gravity of the tread surface of each block constituting the second inclined block row from the center block side to the shoulder block side is set within a range of 20 to 60 °. Has been
At least one of the intermediate blocks constituting the first inclined block row has inclined sides that are inclined within a range of 15 to 60 ° with respect to the tire circumferential direction on the tire rotation direction side and the tire equatorial plane side . ,
The at least one intermediate block constituting the second inclined block row has an inclined side inclined within a range of 15 to 60 ° with respect to the tire circumferential direction on the side opposite to the tire rotation direction and the tire equatorial plane. On the side ,
When the tread is developed in a planar shape, the intermediate block having the inclined side is disposed within a region of 20 to 80% of the tread half width from at least the tire equatorial plane to the shoulder side.
This is a pneumatic tire for motorcycles.   The angle of the first virtual inclination line with respect to the tire equatorial plane and the angle of the second virtual inclination line with respect to the tire equatorial plane are gradually decreased from the tire equatorial plane side toward the shoulder side, respectively. Item 6. The pneumatic tire for a motorcycle according to Item 5.   A method for mounting a pneumatic tire for a motorcycle, wherein the pneumatic tire for a motorcycle according to claim 1 or 2 is used for a rear wheel of the motorcycle.   A method for mounting a pneumatic tire for a motorcycle, wherein the pneumatic tire for a motorcycle according to claim 3 or 4 is used as a front wheel of the motorcycle.   The two-wheeled vehicle pneumatic tire according to claim 1 or 2 is used for a rear wheel of the two-wheeled vehicle, and the two-wheeled vehicle pneumatic tire according to claim 3 or 4 is used for a front wheel. How to install pneumatic tires.

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