JP2004155416A - Pneumatic tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pneumatic tire which can be suitably used especially as a pneumatic tire for a passenger car for summer, and has different tread patterns of a tread portion forming a tread face for traveling between an inner half tread facing the inside of a vehicle when fitted to the vehicle and an outer half tread facing the outside of the vehicle when fitted to the vehicle. <P>SOLUTION: Total area of a recess portion of the inner half tread 1 on the tread face is made larger than that of a recess portion of the outer half tread 2. The inner half tread 1 is provided with at least one inner circumferential groove 7 practically extending in the tire circumferential direction S, and the outer half tread 2 is provided with two circumferential grooves 8, 12 practically extending in the circumferential direction. On at least one, or preferably both of the two circumferential grooves 8, 12, no opening of a lateral groove larger than 1 mm in width and larger than 4 mm, preferably larger than 1 mm in depth is allowed. <P>COPYRIGHT: (C)2004,JPO

Description

  INDUSTRIAL APPLICABILITY The present invention can be preferably used as a pneumatic tire, particularly a pneumatic tire for a passenger car for summer, and a tread pattern of a tread portion forming a tread surface for running, which is directed to the inside of the vehicle when mounted on the vehicle. The present invention relates to a pneumatic tire in which a tread pattern in one half of the surface is different from a tread pattern in a half of the outer tread facing the outside of the vehicle.

  Various conflicting requirements are imposed on pneumatic tires. In particular, in summer tires, good maneuverability needs to be accompanied by low abrasion, low noise generation, and good drainage.

  In order to improve such performance, proposals have been made to make the tread pattern asymmetric inside and outside of the tire equator, for example, including the invention of the asymmetric tread pattern of Patent Document 1.

JP 2000-238510 A

  However, the technique disclosed in Patent Document 1 is for optimizing the drainage performance, the running property, and the noise of the tire and the road surface generated at the time of rolling the tire, and has the same problem as the present invention. The invention has an asymmetrical tread pattern that divides the tread surface into an outer region, an inner region, and a central region in the tire axial direction, and has a lateral groove that almost crosses the central region from the inner region facing inward when the vehicle is mounted. Is required.

  In this case, the water in the central part can be discharged through the lateral groove, and there is a possibility that the drainage property can be improved. There is a concern that comfort may be impaired.

  The present invention relates to a pneumatic tire having good maneuverability, low abrasion, low noise generation, and good drainage improved to the extent possible, particularly for a pneumatic tire that can be suitably used for passenger cars and for summer use. It is intended to be provided.

According to the first aspect of the present invention, the tread pattern of the tread portion having the tread surface for traveling is such that the tread pattern on the tread half (1) inwardly facing the vehicle when mounted on the vehicle and the tread pattern facing outwardly on the vehicle. Different from the outer tread pattern of the outer tread half (2),
The total area of the concave portion of the inner tread half (1) on the tread surface is larger than the total area of the concave portion of the outer tread half (2),
The inner tread half (1) is provided with at least one inner circumferential groove (7) extending substantially in the tire circumferential direction S, and the outer tread half (2) is provided with two substantially tread halves (2). And circumferential grooves (8) and (12) extending in the circumferential direction.
At least one, preferably all circumferential grooves (8), (12) of the outer tread half (2) have transverse grooves with a groove width greater than 1 mm and a groove depth of 4 mm, preferably greater than 1 mm. Are not opened.

The invention according to claim 2 is that the inner and outer tread halves include an inner shoulder block row (3) and an outer shoulder block row (4) in which blocks (5) and (6) are arranged in the tire circumferential direction S. With it,
The width (ba) of the block (6) of the outer shoulder block row (4) in the tire axial direction is larger than the width bi of the block (5) of the inner shoulder block row (3). The invention is characterized in that the blocks (6) of the shoulder block row (4) of the outer tread half (2) comprise transverse grooves (9) separated from each other by inclined transverse grooves (9), the tire equatorial plane Q of said transverse grooves (9). The end on the side is interrupted without communicating with the circumferential groove (8).

Furthermore, the invention according to claim 4, wherein the tread half (1) has at least one other block row (18),
The blocks (19) of the other block row (18) are divided in the tire circumferential direction S by inclined lateral grooves (20) curved in an arc shape,
The end of the inclined lateral groove (20) facing the tire equatorial plane Q is substantially continuous with the arc-shaped portion (22) of the other circumferential groove (21) extending substantially in the tire circumferential direction S. The invention according to claim 5, wherein a circumferential rib (16) extending at least substantially in the tire circumferential direction S is provided on the tire equatorial plane of the tread, and both side edges of the circumferential rib (16) are provided. At least one of the edges is characterized in that a lateral groove having a width in the tire axial direction of more than 1 mm and a groove depth of 4 mm or more, preferably 1 mm or more is not opened.

  In the tire according to the first aspect of the invention, various performances of the tire, such as maneuverability, low noise, abrasion resistance, and drainage, can be improved. In particular, when considering including turning, a uniform distribution of the supporting pressure throughout the entire tread portion can be obtained.

  By making the treads of the inner and outer tread halves different, the inner and outer tread patterns bear opposite functions of the pneumatic tire by the two tread halves. The large "negative surface" (recess) on the tread half 1 improves drainage, and the high rubber ratio (small "negative surface": recess) on the outer tread half 2 enhances maneuverability, especially during turning. sell.

  Furthermore, in at least one, preferably all circumferential grooves of the outer tread half, a lateral groove having a groove width larger than 1 mm and a groove depth of 4 mm, preferably deeper than 1 mm is not opened, This prevents turbulence of the water flowing in the circumferential groove, and thus the two linear circumferential grooves of the outer tread half 2 have the outer grooves despite the fact that the lateral grooves are not open. Can exhibit excellent drainage in half of the tread. Such a configuration significantly affects handling characteristics. By providing a substantially continuous groove edge, disturbance of the water flow in the groove can be prevented, and steering stability can be increased.

  According to the second aspect of the present invention, the width of the outer shoulder block row block in the tire axial direction ba is greater than the width of the inner shoulder block row block bi, thereby providing excellent maneuverability. . Further, in the invention according to claim 3, the blocks of the shoulder block row provided in the outer tread pattern of the outer tread half are separated from each other by a lateral groove, and the end of the lateral groove on the tire equator side is in the circumferential groove. It is formed as a discontinuous end without communication. Thus, leakage of the rotation noise to the outside can be reduced.

  In the invention according to claim 4, on the tire equatorial plane side, the arc of the inclined lateral groove smoothly continues to the arc of the circumferential groove extending substantially in the circumferential direction, so that water is transferred from the peripheral groove to the inclined lateral groove. It can flow in large quantities without being hindered by water, improving drainage. In the invention according to claim 5, handling characteristics can be improved by the central circumferential rib.

  In the present invention, the tread pattern of the tread portion is different from the tread pattern of the half of the tread surface facing the inside of the vehicle when mounted on the vehicle and the tread pattern of the half of the outer tread facing the outside of the vehicle.

  The difference between the inner and outer tread patterns implies that the two tread halves bear different and opposing functions in the pneumatic tire. Good drainage characteristics, large "negative surface" (recess) in the inner tread half improves drainage, high rubber ratio in the outer tread half (relatively small "negative surface": concave) Can enhance the maneuverability, especially when turning. This can be achieved by making the total area on the tread surface of the concave portion including the groove of the inner tread half larger than the total area of the tread surface of the concave portion of the outer tread half. The inner half of the tread particularly helps to improve drainage, and the outer half of the tread enhances maneuverability with a relatively large area of tread rubber. As a result, the pneumatic tire can ensure good maneuverability and drainage for aquaplaning.

  The ratio of the total area of the tread surface of the concave portion of the inner tread half to the total area of the tread surface of the concave portion of the outer tread half is set to the extent of 1.05: 1 to 1.2: 1. This proved to be excellent in performance.

  When the tire sectional ratio (flatness) in the tire meridian sectional view, which is the ratio of the tire width to the tire height, is less than or equal to 60% or less, the total area of the recessed portion of the tread half in the tread surface is: The ratio of the recess of the outer half of the tread to the total area on the tread surface is in the order of 1.04: 1 to 1.08: 1. As a result, an excellent effect is provided for a tire of the above size.

  In the case of a tire having an oblateness of greater than 60%, the ratio of the total area of the inner tread half recesses on the tread surface to the total area of the outer tread half recesses on the tread surface is calculated as For improved performance, the range is from 1.14: 1 to 1.18: 1. And As a result, an excellent effect is provided for a tire of the above size. Note that each “up to” is a range in which 8% of the numerical value of each preceding stage is vertically allowed.

  Further, in the present invention, drainage is improved by providing at least one circumferential groove extending at least substantially in the tire circumferential direction in each of the inner and outer tread halves.

  Further, shoulder block rows composed of blocks arranged in the circumferential direction are provided on the inner and outer tread halves. These blocks can enhance traction and drainage.

  The length of the block of the shoulder block row of the outer tread half (the direction of the rotation axis around which the tire rotates around the axis), that is, the width of the block of the shoulder block row of the inner tread half is larger than the width of the block of the shoulder block row of the inner tread half. Also set to large. By increasing the width of the outer half tread block, the handling characteristics of the tire can be further improved.

  It has been found to be particularly preferred for the width of the outer tread half block to be about 1.1 to about 1.15 times larger than the inner tread half block. .

  Further, in the present invention (the invention according to claim 1), two circumferential grooves are provided in the outer tread pattern of the outer tread half. Thereby, excellent drainage can be obtained regardless of the ratio of the total area of the concave portion on the tread surface being small in the outer tread half. This is particularly preferable when the groove width of the circumferential groove is in the range of 0.05% to 0.065% of the tread width.

  Also, at least one, and preferably all, circumferential grooves of the outer tread half have lateral grooves extending in a direction intersecting with the circumferential direction, and a groove width of about 1 mm or more and a groove of about 4 mm or more, preferably 1 mm or more. Do not open a lateral groove having a depth. These dimensions actually have a significant effect on handling characteristics. By providing a substantially continuous groove edge, disturbance of the water flow in the groove can be prevented, and the flow can be speeded off.

  Also, the outer tread half is provided with at least one circumferentially extending circumferential rib. The circumferential ribs prevent the running noise from escaping to the outside, thereby suppressing the generation of tire noise.

  The blocks of the shoulder block row provided in the tread pattern of the outer half of the tread are separated from each other by a lateral groove, and the end of the lateral groove on the tire equator side is formed as a discontinuous end without communicating with the circumferential groove. . Thus, it is possible to reduce the leakage of the rotation noise to the outside.

  The above-mentioned circumferential rib can be formed at an end boundary of the lateral groove on the tire equator side. With this configuration, it is possible to effectively suppress tire noise.

  As described above, the lateral groove has a discontinuous end, and in order to prevent the rigidity of the outer tread half on the shoulder side from becoming excessively large, the end of the lateral groove on the tire equator side has a small width and a small groove depth. Are connected to each other by a small groove, that is, a separation groove. The separation groove extends at least substantially in the circumferential direction, and preferably has a groove width of 2 mm or less and a groove depth of 4 mm or less. By only partially separating the shoulder block, the advantage of a transverse groove having a discontinuous end may be retained.

  The tread half therein preferably has at least one other block row (referred to as another block example therein), which advantageously divides the tread portion.

  The blocks of the at least one other block row are separated from each other at least in the circumferential direction by inclined lateral grooves extending obliquely. Drainage to the side is made possible by this inclined transverse groove, on the one hand only a slight turbulence is generated, on the other hand, noise generation can be minimized.

  The inclined transverse groove may be curved, for example, arcuate, and preferably comprises a transverse groove between the blocks of the inner shoulder block row and an arc that curves in the same direction. The drainage can thereby be further improved without increasing the generation of noise.

  Since the inclined lateral groove is an arc-shaped inclined lateral groove, the string connecting one end and the other end of the inclined lateral groove has an angle of 20 ° to 45 ° with respect to the tire circumferential direction. Such features provide advantages.

  On the tire equator side, the arc of the inclined lateral groove smoothly continues to the arc of the circumferential groove extending substantially in the circumferential direction. As a result, a large amount of water can flow from the circumferential groove without being hindered by the inclined lateral groove, and drainage is improved.

  Particularly preferably, the arcuate portions of the inner and outer circumferential grooves are directly continuous with one another, the circumferential grooves thus consisting of arcuate portions joined together in an arcade fashion. Thereby, drainage through the inclined lateral groove together with the circumferential groove can be improved.

  On the other hand, the inclined transverse groove can also be opened with a circumferential groove extending at least substantially in the circumferential direction. At this time, the circumferential groove may be linear, and in this case, drainage may be further improved.

  In order to guide and remove water from the central region of the inner tread half to the inside of the tire, in the present embodiment, preferably, the lateral grooves that divide the blocks of the shoulder block row in the inner tread half in the tire circumferential direction are: An opening is similarly made in the inner circumferential groove. As a result, water flows from the other circumferential grooves in the arcade through the inclined lateral grooves and the linear circumferential grooves, flows into the lateral grooves between the shoulder-side blocks, and contacts therethrough. Spills from the ground.

  As a further alternative, at least one further row of blocks is provided which is formed by an interrupted transverse groove having an interrupted end, the interrupted transverse groove being a circumferential groove extending in the tire circumferential direction, in particular a transverse groove of the inner shoulder block row. The starting point is a circumferential groove that opens. Drainage from the interrupted transverse groove is made through the circumferential groove on the straight line and the transverse groove between the blocks in the shoulder row. In a particularly preferred arrangement, the interrupted transverse groove in each block of at least one other block row extends approximately in the center between the two inclined transverse grooves separating the block.

  Also preferably, a central circumferential rib extending at least substantially in the circumferential direction is arranged along the tire equatorial plane at the center of the tread pattern. At this time, the handling characteristics can be improved.

  At least one of the two edges of the circumferential rib is not provided with a lateral groove, and a small groove having a width of at least 1.0 mm or more and 4.0 mm or less, preferably 1.0 mm or less is not opened. This minimizes flow disturbances due to the circumferential ribs.

  In order to further reduce the noise of rolling tires, the number of blocks per block row, the so-called pitch number, should be set between at least two shoulder block rows and one other block row, or a plurality of other block rows. To change between blocks. The maximum spectrum of the generated noise is dispersed, which can be dispersed to reduce peak values.

  The ratio of the pitch number of the shoulder block row to the pitch number of another block row, or one other block row, or a plurality of other block rows is about 1: 1.1 to 1: 1.25. These values have been found to be particularly effective in reducing noise.

  In order to further reduce the noise, the blocks of the two shoulder block rows are offset from each other in the circumferential direction and are displaced. Other blocks, or blocks in a plurality of other blocks, can be similarly offset with respect to the blocks in the shoulder block, and sometimes also in a plurality of other blocks. By this block offset, it is possible to prevent the block from being simultaneously squeezed into the tire contact surface, and to suppress noise generation to a small extent.

  Furthermore, a number of different blocks, especially blocks of different length order, are arranged in two shoulder block rows and / or in one other block row, several other block rows to reduce noise. I do. For this reason, different blocks can be arranged in one of the two shoulder block rows and the other one of the other block rows or a plurality of other block rows. The order is particularly preferably different between the two shoulder block rows. This can further reduce noise.

  As shown in FIG. 1, the tread pattern comprises two tread halves 1, 2 separated by a tire equatorial plane Q. One tread half 1 is an “inner tread half” facing the inside of the vehicle when mounted on the vehicle (hereinafter referred to as “inner tread half 2”), and the other tread half 2 faces the outside of the vehicle. Half 2 ".

  The inner and outer tread halves 1 and 2 are provided with shoulder block rows 3 and 4 composed of blocks 5 and 6 provided in the circumferential direction S, respectively. The shoulder blocks 5 and 6 of the shoulder block rows 3 and 4 extend from the shoulder to the tire sidewall region, and are partitioned by circumferential grooves 7 and 8 on the tire equatorial plane Q side. The width bi of the shoulder block 5 in the tire axial direction (the direction of the rotation axis of the tire, that is, the direction crossing the tire equatorial plane Q) (that is, from the edge of the circumferential groove 7 to the inner edge ri of the facing contact surface). In the above, the width ba of the outer shoulder block row 4 from the edge of the circumferential groove 8 to the outer edge ra of the facing tire contact surface is small. The difference between the lengths is about 10 to 15%.

  The blocks 6 of the outer shoulder block row 4 are separated by an arc-shaped outer lateral groove 9 that goes beyond the outer edge ra and enters the sidewall region. On the side facing the tire equatorial plane Q, the outer lateral groove 9 has a discontinuous end that terminates in a discontinuous manner, so that the outer lateral groove 9 does not open in the circumferential groove 8 but extends in the outer block extending in the circumferential direction. Are bounded by the circumferential rib 10. The outer lateral grooves 9 are connected to each other by a separation groove 11 extending in the circumferential direction S on the side facing the tire equatorial plane Q (near a break), and the separation groove 11 has a groove width of 1 to 4 mm, 2 mm in this example. It has a groove depth of 2 to 6 mm, in this example 4 mm.

  In the outer tread half 2, in addition to the outer circumferential groove 8, another outer circumferential groove 12 extending in the circumferential direction S is formed. Are defined by the circumferential ribs 16. In the present embodiment, each of the circumferential grooves 8 and 12 has a straight shape, and sandwiches the outer intermediate circumferential rib 13. Therefore, the edge of the circumferential rib 13 has a straight shape. The two circumferential grooves 8, 12 do not further open a groove having a groove width of 1 mm or more and a groove depth of 4 mm, preferably 1 mm or more. The outer intermediate circumferential rib 13 extends laterally and extends between the other outer circumferential groove 12 and the narrow circumferential groove 15 provided in the rib 13. A narrow lateral groove 14 is provided. Another outer circumferential groove 12 is bounded on the tire equatorial plane Q side by the circumferential rib (the circumferential rib 10 in the outer block) and the corresponding edge of the outer middle circumferential rib 13. As with the edge of the central circumferential rib 16, no interruptions are formed.

  Similarly, the blocks 5 of the inner shoulder block row 3 are separated from each other in the circumferential direction S by the arc-shaped inner lateral groove 17. The inner lateral groove 17 extends to the sidewall region beyond the inner edge ri. On the tire equatorial plane Q side, the inner lateral groove 17 is opened in the linear inner circumferential groove 7 without a break. Further, the lateral groove 17 in the inner shoulder block row 3 has an arc shape opposite to the lateral groove 9 in the outer shoulder block row 4.

  In the inner tread half 1, a block 19 is separated from one another in the circumferential direction S by an inclined lateral groove 20 extending inclining and includes another block row 18 therein. The inclined lateral groove 20 has a curved shape, for example, an arc shape, and an end facing inward is opened by the inner circumferential groove 7. The other end of the inclined lateral groove 20 is not linear, and the inclined lateral groove 20 is connected to another circumferential groove 21 in which the arc-shaped portions 22 are connected to each other in an arcade shape. 22 are connected so as to be continuously and smoothly connected. In this embodiment, the arc portions 22 are directly joined to each other.

  As described above, the inner circumferential groove 7, the inner horizontal groove 17, the inclined horizontal groove 20, and the interrupted horizontal groove 23 described later are opened. Further, the curved inclined lateral groove 20 has a string connecting both ends thereof having a tire equatorial plane Q and an eggplant angle α of not less than 20 ° and not more than 45 °.

  Starting from the inner circumferential groove 7, the interrupted transverse groove 23 extends into the block 19 of the other block row 18 and has an interrupted end in the inner tread half 1, and the two lines that bound the block 19. The groove extends substantially at the center of the inclined lateral groove 20. The discontinuous lateral groove 23 having a discontinuous end has the same angle α (20 ° or more, preferably 25 ° or more, and 45 ° or less, preferably 38 ° or less) with respect to the tire equatorial plane Q at the same angle as the inclined lateral groove 20. It is set at about 30 °.

  The other inner circumferential groove 21, on the other hand, is bounded by a central circumferential rib 16, and the central circumferential rib 16 bounds another outer circumferential groove 12. The edge of the central circumferential rib 16 facing the other circumferential groove 21 does not have a lateral groove entrance. A narrow central groove 24 extends circumferentially on the tire equatorial plane Q of the central circumferential rib 16.

  As is clear from the figure, the blocks 5, 6 of the inner and outer shoulder blocks 3, 4 have different circumferential lengths Li, La between the blocks 5, 6 and the blocks 5, 6 arranged in the circumferential direction. Similarly, the blocks 19 of the other block rows 18 in the tread half 1 have the circumferential length Lm changed according to the blocks 19 arranged in a line. The block 5 of the inner shoulder block row 3 is displaced (offset) with respect to the block 6 of the outer shoulder block row 4, and both of them are also in the tire circumferential direction with respect to the block 19 of the other inner block row 18. The position can be shifted to S.

  In this manner, in a number of blocks 5, 6, 19 having different lengths Li, La, Lm, it can be changed between the shoulder block rows 3 and 4 on both sides and between the other block rows 18 therein. The order of the blocks 5, 6 and 19 between the two shoulder block rows 3 and 4, including the tire block row 18 and the tire block row (which may be added) block row, is included. Can change. Also, the order of the blocks can be changed between the blocks 5 and 6 of the two shoulder block rows.

  Further, the number of blocks 5 and 6 in the inner and outer shoulder block rows 3 and 4 can be different from the number of blocks 19 in the other inner block row 18. When the cross-sectional ratio, that is, the flattening ratio (tire cross-section height / tire cross-section width) is 60% or less, the total number of blocks divided by the interrupted lateral groove 23 of the block 19 in the other block row 18 is calculated as For example, the number of blocks 5 and 6 in the outer shoulder block rows 3 and 4 is, for example, larger than 1.0 times, and preferably 1.05 times or more, and the upper limit is 1.25 times, preferably 1.20 times. Up to the extent. Further, in a tire having an aspect ratio of more than 60%, the total number of blocks divided by the interrupted lateral groove 23 of the block 19 of the other block row 18 is changed to the block 5 of the inner and outer shoulder block rows 3 and 4. For example, the number of 6 is larger than 1.0 times, preferably 1.05 times or more, and the upper limit is 1.25, preferably 1.17 times. As a whole, the range is 1:05 or more, preferably 1:11 or more and 1: 125 or less.

  As is clear from the drawing, the total area of the tread surface of the tread half 1 among the recesses which are removed from the running tread surface, that is, the recesses usually called “negative surfaces”, is reduced by the recesses of the outer tread half 2 Is larger than the total area. This means that the total area of all the circumferential grooves 7, 21 and all the lateral grooves 17, 20, 23 is larger than the total area of the circumferential grooves 8, 12 and the horizontal grooves 9 of the outer tread half 2. It means there is. For a tire having an aspect ratio of 60% or less, the tire preferably has an aspect ratio of 1.06: 1 (approximately 1.05 to 1.20, preferably 1.04 to 1.08: 1). Is large, it is preferably 1.16: 1 (an allowable range of about 1.05 to 1.20, and preferably about 1.14 to 1.18: 1). You can also choose.

  With such a configuration, in the tire of the present invention, various performances of the tire, such as maneuverability, low noise, abrasion resistance, and drainage, can be improved. Furthermore, a uniform distribution of the supporting pressure throughout the entire tread portion is also possible.

  By making the treads of the inner and outer tread halves 1 and 2 different, good drainage characteristics are achieved, while the large “negative surface” (recess) of the inner tread half 1 improves drainage, and the outer tread half A high rubber ratio of 2 (small "negative surface": recess) can enhance maneuverability, especially when turning. In particular, since the width ba of the block 6 of the outer shoulder block row 4 in the tire axial direction is larger than the width bi of the block 5 of the inner shoulder block row 3, excellent maneuverability is provided. The two linear circumferential grooves 8, 12 of the outer tread half 2 can exhibit excellent drainage in the outer tread half 2, despite the fact that the lateral grooves are not open.

  Low noise is due, among other things, to a circumferential rib 10 in the outer block which bounds the outer transverse groove 9 between the outer blocks 6 of the outer shoulder block row 2. Prevents the sound in the region from the center to its inner part from flowing out.

FIG. 2 is a plan view of a tread pattern illustrating a preferred embodiment of the present invention.

Explanation of reference numerals

1 inner tread half 2 outer tread half 3 inner shoulder block row 4 outer shoulder block row 5 block 6 block 7 inner circumferential groove 8 outer circumferential groove 9 outer lateral groove 10 outer circumferential block inside Other circumferential grooves 13 outside the ribs 13 Intermediate circumferential ribs 14 outside the narrow narrow grooves 15 Narrow circumferential grooves 16 Other block rows 19 in the horizontal grooves 18 in the central circumferential rib 17 Blocks 20 Slant horizontal grooves 21 Other circumferential groove 22 inside arc-shaped portion 23 interrupted lateral groove 24 narrow central groove

Claims (5)

The tread pattern of the tread portion having the running tread surface is such that the tread pattern on the inner tread half (1) facing the vehicle inside when mounted on the vehicle and the outer tread half (2) facing the vehicle outside. Different from the tread pattern of
The total area of the concave portion of the inner tread half (1) on the tread surface is larger than the total area of the concave portion of the outer tread half (2),
The inner tread half (1) is provided with at least one inner circumferential groove (7) extending substantially in the tire circumferential direction S, and the outer tread half (2) is provided with two substantially tread halves (2). And circumferential grooves (8) and (12) extending in the circumferential direction.
At least one, preferably all circumferential grooves (8), (12) of the outer tread half (2) have transverse grooves with a groove width greater than 1 mm and a groove depth of 4 mm, preferably greater than 1 mm. A pneumatic tire characterized by having no opening. The inner and outer tread halves include an inner shoulder block row (3) in which blocks (5) and (6) are arranged in the tire circumferential direction S, and an outer shoulder block row (4),
The width (ba) of the block (6) of the outer shoulder block row (4) in the tire axial direction is larger than the width bi of the block (5) of the inner shoulder block row (3). 2. The pneumatic tire according to 1.   The block (6) of the shoulder block row (4) of the outer tread half (2) has a transverse groove (9) separated from each other by an inclined transverse groove (9), and the end of the transverse groove (9) on the tire equatorial plane Q side. The pneumatic tire according to claim 1 or 2, wherein the portion is interrupted without communicating with the circumferential groove (8). Said inner tread half (1) comprises at least one other block row (18);
The blocks (19) of the other block row (18) are divided in the tire circumferential direction S by inclined lateral grooves (20) curved in an arc shape,
The end of the inclined lateral groove (20) on the side facing the tire equatorial plane Q is substantially continuous with the arc-shaped portion (22) of another circumferential groove (21) extending in the tire circumferential direction S. The pneumatic tire according to any one of claims 1 to 3, wherein the pneumatic tire is connected to a pneumatic tire.   A circumferential rib (16) extending at least substantially in the tire circumferential direction S is provided on the tire equatorial plane of the tread, and at least one of both side edges of the circumferential rib (16) has a tire shaft. The pneumatic tire according to any one of claims 1 to 4, wherein a lateral groove having a width in the direction of more than 1 mm and a groove depth of 4 mm or more, preferably 1 mm or more, is not opened.

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