Abstract:
Provided is a pneumatic tire which has both improved driving stability performance on a dry road surface and improved on-snow performance. A pneumatic tire has defined on the tread first lands and second lands. The first lands and the second lands are provided with recesses. The recesses include first recesses provided in first edges of the first lands, and also include second recesses provided in second edges of the second lands. The second recesses are provided so as not to intersect projection regions formed by projecting the first recesses onto the second edges in the axial direction of the tire.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a pneumatic tire which may improve on-snow performance with steering stability on dry road. 
       BACKGROUND ART 
       [0002]    In recent years, pneumatic tires have been required an excellent traveling performance on snowy road (hereinafter, referred to as on-snow performance). 
         [0003]    In order to improve on-snow performance, a pneumatic tire including a tread portion provided with a groove and a sipe has been proposed. Unfortunately, such a pneumatic tire had a problem that the steering stability on dry road tends to deteriorate owing to lowering of rigidity of the tread portion by the groove and the sipe. 
         [0004]    The following Patent document 1 discloses a pneumatic tire including a recess provided on an edge of a land portion of a tread portion. Such a pneumatic tire may maintain rigidity of the land portion to ensure steering stability on dry road. 
         [0005]    Unfortunately, the pneumatic tire disclosed by Patent document 1 has room for further improvement with respect to achieve the steering stability on dry road with on-snow performance. 
         [0000]    Patent document 1: Japanese Unexamined Patent Application Publication No. 2000-52715 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0006]    The present invention has been made in view of circumstances described above, and has a main object to provide a pneumatic tire which achieves steering stability on dry road with on-snow performance based on improved arrangement of recesses provided on a land portion. 
       Solution to Problem 
       [0007]    The present invention provides a pneumatic tire including a tread portion being provided with at least one circumferentially and continuously extending main groove to separate a first land portion located on one side of the main groove and a second land portion located on the other side of the main groove, a recess being provided on the first land portion and the second land portion, the recess including a plurality of first recesses provided on a first edge of the first land portion wherein the first edge faces the main groove and a plurality of second recesses provided on a second edge of the second land portion wherein the second edge faces the main groove, and each second recess being arranged so as not to overlap each projected region in which each first recess is projected onto the second edge in an axial direction of the tire. 
         [0008]    In the pneumatic tire according to the invention, preferably, each recess includes a substantially tetrahedron void surrounded by four triangular surfaces, and the substantially tetrahedron including a first surface located on a ground contact surface of the first or second land portion, a second surface located on a groove wall of the main groove, a third surface forming a bottom side of the recess, and a fourth surface facing the second surface. 
         [0009]    In the pneumatic tire according to the invention, preferably, the third surface is a spherical triangle surface that protrudes radially outwardly. 
         [0010]    In the pneumatic tire according to the invention, preferably, the third surface of each first recess slopes radially inwardly toward one side in a circumferential direction of the tire, and the third surface of each second recess slopes radially inwardly toward the other side in the circumferential direction of the tire. 
         [0011]    In the pneumatic tire according to the invention, preferably, the second land portion is provided with a lug groove having one end connected to the main groove and the other end terminates within the second land portion, and the lug groove is arranged so as to overlap with one of the projected regions of the first recesses. 
         [0012]    In the pneumatic tire according to the invention, preferably, the second land portion is provided with a lateral groove on an opposite edge to the second edge, and the lateral groove is communicated with one of the second recesses. 
         [0013]    In the pneumatic tire according to the invention, preferably, a maximum depth of the recess is in a range of from 0.5 to 0.95 times a depth of the main groove. 
         [0014]    In the pneumatic tire according to the invention, preferably, a circumferential distance between the first recess and the second recess is in a range of from 0.9 to 1.1 times a width of the main groove. 
         [0015]    The present invention also provides a pneumatic tire including a tread portion being provided with a plurality of circumferentially and continuously extending main grooves to form a land portion therebetween, a plurality of recesses being provided on the land portion, the recesses including a plurality of recesses provided on an axially one side edge of the land portion and a plurality of recesses provided on an axially other side edge of the land portion, and each recess provided on the one side edge is arranged so as not to overlap with each projected region in which each recess provided on the other side edge is projected onto the one side edge in an axial direction of the tire. 
         [0016]    In the pneumatic tire according to the invention, preferably, the main grooves include a pair of circumferentially and continuously extending shoulder main grooves each deposed proximate each tread edge and a circumferentially and continuously extending crown main groove arranged between the shoulder main grooves to form second land portions each between the shoulder main groove and the crown main groove on each side of a tire equator, each second land portion is provided with a plurality of lug grooves extending axially outwardly from the crown main groove and terminating within the second land portion, a plurality of lateral grooves extending axially inwardly from the shoulder main groove and terminating within the second land portion and the second recess provided between a pair of circumferentially adjacent lug grooves on an edge on the side of the crown main groove of the second land portion, and the lug grooves and the lateral grooves are arranged alternately in a circumferential direction of the tire. 
         [0017]    In the pneumatic tire according to the invention, preferably, the second recess includes a substantially triangular recess bottom surface, the recess bottom surface being smoothly connected to a ground contact surface of the second land portion, the recess bottom surface extending toward a bottom of the second recess while increasing a depth of the second recess and reducing a width of the recess bottom surface in the axial direction of the tire from the ground contact surface toward the bottom, the recess bottom surface includes a first side extending on a sidewall of the second land portion, a second side to define a boundary with respect to the ground contact surface, and a third side disposed between the first side and the second side, and the first side has a length greater than that of the third side. 
         [0018]    In the pneumatic tire according to the invention, preferably, an angle between the second side and the third side is an obtuse angle. 
         [0019]    In the pneumatic tire according to the invention, preferably, the second recess includes a recess sidewall extending radially outwardly from the third side in a substantially planar shape. 
         [0020]    In the pneumatic tire according to the invention, preferably, the lateral grooves include a steep inclined portion having an angle with respect to the circumferential direction of the tire wherein the angle gradually decreases axially inwardly, and the second land portion is provided with a connection sipe connecting between the second recess and the steep inclined portion. 
         [0021]    In the pneumatic tire according to the invention, preferably, a depth of the steep inclined portion gradually increases axially outwardly. 
         [0022]    In the pneumatic tire according to the invention, preferably, circumferential arrangement pitches of lug grooves are greater than an axial width of the second land portion. 
         [0023]    In the pneumatic tire according to the invention, preferably, the arrangement pitches are in a range of from 2.0 to 3.3 times the axial width of the second land portion. 
         [0024]    In the pneumatic tire according to the invention, preferably, an inclined sipe extending axially inwardly from the shoulder main groove and terminating within the second land portion is provided. 
       Advantageous Effects of Invention 
       [0025]    The pneumatic tire according to a first aspect of the invention includes the tread portion provided with at least one circumferentially and continuously extending main groove to separate the first land portion located on one side of the main groove and the second land portion located on the other side of the main groove. The recess is provided on the first land portion and the second land portion. Such a recess may compress snow introduced therein effectively, and then may generate large snow-shearing force by shearing the compressed snow. Thus, traction performance on snowy road can be improved. 
         [0026]    The recess includes a plurality of first recesses provided on the first edge of the first land portion wherein the first edge faces the main groove and a plurality of second recesses provided on the second edge of the second land portion wherein the second edge faces the main groove. Each second recess is arranged so as not to overlap each projected region in which each first recess is projected onto the second edge in the axial direction of the tire. Such first and second recesses may ensure rigidity of land portions effectively to achieve an excellent steering stability on dry road while maintaining snow traction in the circumferential direction of the tire. 
         [0027]    The pneumatic tire according to a second aspect of the invention includes the tread portion provided with a plurality of circumferentially and continuously extending main grooves to form a land portion therebetween. The land portion is provided with a plurality of recesses. The recesses include a plurality of recesses provided on an axially one side edge of the land portion and a plurality of recesses provided on an axially other side edge of the land portion. Such recesses may improve traction performance when traveling on snowy road by obtaining a large snow-shearing force on the snowy road. 
         [0028]    Each recess provided on the one side edge is arranged so as not to overlap with each projected region in which each recess provided on the other side edge is projected onto the one side edge in the axial direction of the tire. Such recesses may ensure rigidity of the land portion effectively to achieve an excellent steering stability on dry road while maintaining snow traction in the circumferential direction of the tire. 
         [0029]    Accordingly, the pneumatic tire in accordance with the present invention may achieve steering stability on dry road with on-snow performance. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0030]      FIG. 1  is a development view of a tread portion of a pneumatic tire according to an embodiment of the invention. 
           [0031]      FIG. 2  is a cross-sectional view taken along a line A-A of  FIG. 1 . 
           [0032]      FIG. 3  is an enlarged perspective view of a main groove and a land portion illustrated in  FIG. 1 . 
           [0033]      FIG. 4  is an enlarged perspective view of a recess illustrated in  FIG. 3 . 
           [0034]      FIG. 5A  is an enlarged perspective view of a first surface of the recess and  FIG. 5B  is an enlarged perspective view of a second surface of the recess. 
           [0035]      FIG. 6A  is an enlarged perspective view of a third surface of the recess and  FIG. 6B  is an enlarged perspective view of a fourth surface of the recess. 
           [0036]      FIG. 7  is an enlarged view of a first land portion illustrated in  FIG. 1 . 
           [0037]      FIG. 8  is an enlarged view of a second land portion illustrated in  FIG. 1 . 
           [0038]      FIG. 9A  is a cross-sectional view of a lug groove taken along a line B-B of  FIG. 8 , and  FIG. 9B  is a cross-sectional view of a lateral groove taken along a line C-C of  FIG. 8 . 
           [0039]      FIG. 10  is an enlarged perspective view of a second recess illustrated in  FIG. 8 . 
           [0040]      FIG. 11  is an enlarged view of a third land portion illustrated in  FIG. 1 . 
       
    
    
     REFERENCE SIGNS LIST 
       [0000]    
       
         
           
               2  Tread portion 
               3  Main groove 
               11  First land portion 
               12  Second land portion 
               11   e  First side 
               12   e  Second side 
               17  Projected region 
               30  Recess 
               31  First recess 
               32  Second recess 
           
         
       
     
       DESCRIPTION OF EMBODIMENTS 
       [0051]    An embodiment of the present invention will be explained below to the accompanying drawings.  FIG. 1  is a development view of a tread portion  2  of a pneumatic tire (hereinafter, simply referred to as “tire”)  1  in accordance with an embodiment of the present invention. The pneumatic tire  1  according to the embodiment, for instance, is preferably embodied as a radial tire for passenger cars. 
         [0052]    As illustrated in  FIG. 1 , the tread portion  2  is provided with a plurality of circumferentially and continuously extending main grooves  3 . As used herein, “main groove” means a groove that extends continuously in a circumferential direction of the tire and has a width of 2% or more a tread width TW. 
         [0053]    The tread width TW is an axial distance between tread edges Te and Te of the tire  1  placed under a standard state. The standard state is such that the tire is mounted on a standard wheel rim (not shown) with a standard pressure, but is loaded with no tire load. 
         [0054]    The standard wheel rim is a wheel rim officially approved or recommended for the tire by standards organizations, wherein the standard wheel rim is the “standard rim” specified in JATMA, the “Measuring Rim” in ETRTO, and the “Design Rim” in TRA or the like, for example. 
         [0055]    The standard pressure is a standard pressure officially approved or recommended for the tire by standards organizations, wherein the standard pressure is the “maximum air pressure” in JATMA, the “Inflation Pressure” in ETRTO, and the maximum pressure given in the “Tire Load Limits at Various Cold Inflation Pressures” table in TRA or the like, for example. 
         [0056]    The tread edge is an axially outermost ground contact edge of a ground contact patch of the tire which is obtained by loading with a standard tire load on the tire placed under the standard state with at a camber angle of zero. 
         [0057]    As used herein, the standard tire load is a tire load officially approved or recommended for the tire by standards organizations, wherein the standard load is the “maximum load capacity” in JATMA, the “Load Capacity” in ETRTO, and the maximum value given in the above-mentioned table in TRA or the like. 
         [0058]    The main grooves  3  include a crown main groove  4  and a shoulder main groove  5 . 
         [0059]    A pair of the shoulder main grooves  5  are arranged so that the tire equator C is located therebetween wherein each is located nearest to each tread edge Te. In this embodiment, the shoulder main grooves  5 , for example, extend in a straight shape in the circumferential direction of the tire. 
         [0060]    A pair of crown main grooves  4  are arranged between the shoulder main grooves  5  and  5  wherein the tire equator C is located between the crown main grooves  4 . In this embodiment, the crown main grooves  4 , for example, extend in a straight shape in the circumferential direction of the tire. 
         [0061]    The widths W 4  of the crown main grooves  4  and the widths W 5  of the shoulder main grooves  5 , for example, are preferably in a range of from 2.5% to 7.5% the tread width TW. These crown main grooves  4  and shoulder main grooves  5  may achieve steering stability on dry road with on-snow performance. In this embodiment, the widths W 4  and W 5  of the crown main grooves  4  and the shoulder main grooves  5  respectively are substantially constant. 
         [0062]      FIG. 2  illustrates a cross-sectional view taken along a line A-A of  FIG. 1 . As illustrated in  FIG. 2 , the depths d 4  of the crown main grooves  4  and the depths d 5  of the shoulder main grooves  5 , for example, are preferably in a range of from 5 to 15 mm as for a tire for passenger cars according to the embodiment. 
         [0063]    As illustrated in  FIG. 1 , the tread portion  2  is separated into a plurality of land portions  10  between the main grooves  3  and  3  by providing a plurality of main grooves  3 . The land portions  10 , for example, include a first land portion  11 , a pair of second land portion  12  and a pair of third land portions  13 . In this embodiment, the first land portion  11  is disposed between a pair of the crown main grooves  4  and  4 . Each of the second land portions  12  is disposed between one of the crown main grooves  4  and one of the shoulder main grooves  5 . Each of the third land portions  13  is disposed axially outward of each shoulder main groove  5 . 
         [0064]      FIG. 3  illustrates an enlarged perspective view of a region  38  surrounded by two-dot chain line of  FIG. 1 . In  FIG. 3 , one of the crown main grooves  4  for the main grooves  3 , the first land portion  11  located on one side of the crown main groove  4 , and the second land portion  12  located on the other side of the crown main groove  4  are illustrated. 
         [0065]    As illustrated in  FIG. 3 , each of the first land portion  11  and the second land portion  12  is provided with a plurality of recesses  30 . The recesses  30  may compress snow introduced therein effectively, and then may generate large snow-shearing force by shearing the compressed snow. Thus, traction performance on snowy road can be improved. 
         [0066]    As illustrated in  FIG. 1 , the recess  30  includes a plurality of first recesses  31  provided on a first edge  11   e  of the first land portion  11  wherein the first edge  11   e  faces the main groove  3  and a plurality of second recesses  32  provided on a second edge  12   e  of the second land portion  12  wherein the second edge  12   e  faces the main groove  3 . 
         [0067]    Each second recess  32  is arranged so as not to overlap each projected region  17  in which each first recess  31  is projected onto the second edge  12   e  in the axial direction of the tire. These first recesses  31  and second recesses  32  may ensure rigidity of land portions  10  effectively to achieve an excellent steering stability on dry road while maintaining snow traction in the circumferential direction of the tire. 
         [0068]      FIGS. 4 to 6  each illustrate an enlarged perspective view of the recesses  30 . As illustrated in  FIG. 4 , the recess  30  is a void having a substantially tetrahedron shape  40  provided on the land portions  10  and which is surrounded by four triangular surfaces. As illustrated in  FIGS. 5A, 5B, 6A and 6B , the substantially tetrahedron shape  40  includes a first surface  41 , a second surface  42 , a third surface  43  and a fourth surface  44 . 
         [0069]    As illustrated in  FIG. 5A , the first surface  41  is located on the ground contact surface  10   s  of the land portion  10 . The first surface  41  is indicated by hatching in  FIG. 5A . 
         [0070]    The first surface  41  has a triangular shape having a first side  41   a , a second side  41   b  and a third side  41   c . The first side  41   a  corresponds to a virtual extension  39  of the edge  10   e  and which extends along the circumferential direction of the tire. The second side  41   b , for example, is shorter than the first side  41   a , and extends on the ground contact surface  10   s  of the land portion  10  with an inclination with respect to the circumferential direction of the tire. The third side  41   c , for example, is the shortest in three sides, and extends on the ground contact surface  10   s  of the land portion  10 . The angle θ 4  between the first side  41   a  and the second side  41   b , for example, is in a range of from 5 to 30 degrees. 
         [0071]    As illustrated in  FIG. 5B , the second surface  42  is a surface located on a sidewall  3   w  of the main groove  3 . The second surface  42  is indicated by hatching in  FIG. 5B . The second surface  42  has a triangular shape including a first side  42   a , a second side  42   b  and a third side  42   c . The first side  42   a  is a virtual extension  39  of the edge  10   e  of the land portion  10 , and corresponds to the first side  41   a  (shown in  FIG. 5A ) of the first surface  41 . The second side  42   b  extends from the ground contact surface  10   s  of the land portion  10  to the deepest portion  30   d  of the recess on the sidewall  3   w  of the main groove  3  with an inclination with respect to the circumferential direction of the tire. The third side  42   c  is shorter than the first side  42   a  and the second side  42   b , and extends in a depth direction of the main groove  3  within the sidewall  3   w  of the main groove  3 . 
         [0072]    As illustrated in  FIG. 6A , the third surface  43  forms a bottom surface  33  of the recess  30 . The third surface  43  is indicated by hatching in  FIG. 6A . 
         [0073]    Preferably, the third surface  43  is connected smoothly with the ground contact surface  10   s  of the land portion  10 . The third surface  43  is inclined with respect to the ground contact surface  10   s  so as to increase the depth of the recess  30  in one side or the other side in the circumferential direction of the tire. In this embodiment, the third surface  43  is a spherical triangle surface that protrudes radially outwardly. Such a third surface  43  may introduce snow into the recess  30  when traveling on snowy road, and compress it effectively. Accordingly, an excellent traveling performance on-snow performance can be achieved by generating large snow-shearing force. 
         [0074]    The third surface  43  includes a first side  43   a , a second side  43   b  and a third side  43   c . The first side  43   a  extends from the ground contact surface  10   s  of the land portion  10  to the deepest portion  30   d  of the recess on the sidewall  3   w  of the main groove  3  while inclining with respect to the circumferential direction of the tire. The first side  43   a  of the third surface  43  corresponds to the second side  43   b  (shown in  FIG. 5B ) of the second surface  42 . 
         [0075]    The second side  43   b  of the third surface  43  is the shortest side in the sides of the third surface  43 , and which extends on the ground contact surface  10   s  of the land portion. The third side  43   c  extends from the ground contact surface  10   s  of the land portion  10  toward the deepest portion  30   d  of the recess while inclining with respect to the circumferential direction of the tire. 
         [0076]    The vertex angle θ 1  of the bottom surface  33  formed between the first side  43   a  and the third side  43   c  of the third surface  43  is preferably in a range of not less than 5 degrees, more preferably not less than 15 degrees, but preferably not more than 30 degrees, more preferably not more than 20 degrees. Thus, the recess may have a sufficient volume that may compress the snow introduced in the recess  30  effectively. 
         [0077]    The edge side angle θ 2  of the bottom surface  33  formed between the first side  43   a  and the second side  43   b  of the third surface  43  is preferably in a range of not less than 45 degrees, more preferably not less than 60 degrees, but preferably not more than 90 degrees, more preferably not more than 75 degrees. Such a bottom surface  33  may introduce snow into the recess  30  effectively when cornering, and therefore cornering performance on snowy road can be improved. 
         [0078]    The inclined angle θ 3  formed between the first surface  41  (shown in  FIG. 5A ) and the third surface  43  is preferably in a range of not less than 5 degrees, more preferably not less than 8 degrees, but preferably not more than 15 degrees, more preferably not more than 12 degrees. Such a third surface  43  may maintain a sufficient volume of the recess  30  while ensuring rigidity of the land portion. Thus, the steering stability on dry road as well as on-snow performance can be improved. 
         [0079]    Preferably, the inclined angle θ 3  increases toward the deepest portion  30   d  of the recess  30  from the side of the ground contact surface  10   s . With this, the snow introduced in the recess  30  is compressed more effectively when traveling on snowy road. Accordingly, a large snow-shearing force may be obtained and offer an excellent on-snow performance. 
         [0080]    As illustrated in  FIG. 6B , the fourth surface  44  is a surface on the side of the land portion  10  and which faces the second surface  42  (shown in  FIG. 5B ). The fourth surface  44  is indicated by hatching in  FIG. 6B . 
         [0081]    The fourth surface  44  is connected substantially vertically to the third surface  43  (shown in  FIG. 6A ). The fourth surface  44  extends along the radial direction of the tire. The fourth surface  44 , for example, is formed as a flat surface or a curved surface that is bent smoothly. Such a fourth surface  44  may compress snow introduced in the recess  30  along the third surface strongly toward the main groove  3  when traveling on snowy road. Accordingly, a large snow-shearing force may be obtained, and in particular cornering performance on snowy road can be improved. 
         [0082]    The fourth surface  44  has a triangular shape including a first side  44   a , a second side  44   b  and a third side  44   c . The first side  44   a  extends on the ground contact surface  10   s  of the land portion  10  with an inclination with respect to the circumferential direction of the tire. The second side  44   b  extends on the sidewall  3   w  of the main groove  3  in the depth direction of the main groove  3 . The third side  44   c  extends from the ground contact surface  10   s  of the land portion  10  toward the deepest portion  30   d  of the recess  30  while inclining with respect to the circumferential direction of the tire. 
         [0083]    As illustrated in  FIG. 4 , the width W 1  of the recess  30  in the axial direction of the tire is preferably in a range of not less than 0.2 times, more preferably not less than 0.25 times, but preferably not more than 0.4 times, more preferably not more than 0.35 times the width W 2  of the land portion  10  on which the recess  30  is provided. Such a recess  30  may improve on-snow performance while ensuring rigidity of the land portion  10 . 
         [0084]    A ratio W 1 /L 1  of the axial width W 1  of the recess  30  to the circumferential length L 1  of the recess is preferably in a range of not less than 0.15, more preferably not less than 0.18, but preferably not more than 0.25, more preferably not more than 0.22. Such a recess  30  may improve traction on snowy road as well as cornering performance in a well balanced manner. 
         [0085]    The maximum depth d 1  of the recess  30  is preferably in a range of not less than 0.5 times, more preferably not less than 0.6 times, but preferably not more than 0.95 times, more preferably not more than 0.75 times the depth d 2  of the main groove  3 . Such a recess  30  may achieve the steering stability on dry road with on-snow performance. 
         [0086]    As illustrated in  FIG. 1 , a circumferential length L 2  between circumferentially adjacent first recess  31  and the second recess  32  is preferably in a range of not less than 0.9 times, more preferably not less than 0.95 time, but preferably not more than 1.1 times, more preferably not more than 1.05 times the width W 3  of the main groove  3 . These first recess  31  and second recess  32  may achieve a large snow-shearing force while maintaining rigidity uniformity of the land portion  10 . 
         [0087]    As illustrated in  FIG. 3 , preferably, the third surface  43  of the first recess  31  is inclined radially inwardly toward one side in the circumferential direction of the tire, and the third surface  43  of the second recess  32  is inclined radially inwardly toward the other side in the circumferential direction of the tire. These first recess  31  and second recess  32  may obtain a large snow-shearing force in both situations of acceleration and braking. Accordingly, on-snow performance can be further improved. 
         [0088]      FIG. 7  illustrates a partial enlarged view of the first land portion  11 . The tread portion  2  according to the present embodiment is designed as a point symmetrical pattern with respect to an arbitrary point on the tire equator C. Accordingly, a plurality of the recesses  30  are provided on the both first edges  11   e  of the first land portion  11 , as shown in  FIG. 7 . Such recesses  30  may obtain a large snow-shearing force from around the tire equator where a large ground contact pressure acts when traveling on snowy road, and may further improve snow traction. 
         [0089]    Each first recess  31 A provided on the one side of the first edge  11   e  is arranged so as not to overlap with each projected region  18  in which each first recess  31 B provided on the other side of the first edge  11   e  is projected onto the one side of the first edge  11   e . Such recesses  30  may ensure rigidity of the land portion on which recesses are provided effectively to achieve an excellent steering stability on dry road while maintaining snow traction in the circumferential direction of the tire. 
         [0090]    A circumferential distance between the first recess  31 A provided on the one side of the first edge  11   e  and the first recess  31 B provided on the other side of the first edge  11   e  is preferably in a range of not less than 1.05 times, more preferably not less than 1.1 times, but preferably not more than 1.2 times, more preferably not more than 1.15 times the width W 6  of the first land portion  11 . Such recess  30  may maintain a large snow-shearing force while ensuring rigidity uniformity of the first land portion  11 . 
         [0091]    In this embodiment, the first land portion  11  is preferably formed as a rib extending continuously in the circumferential direction of the tire. The width W 6  of the first land portion  11  in the axial direction of the tire, for example, is in a range of from 0.1 to 0.15 times the tread width TW (shown in  FIG. 1 , hereinafter the same). Such a first land portion  11  may offer an excellent steering stability due to its high circumferential rigidity. 
         [0092]    Preferably, a circumferentially and continuously extending circumferential sub groove  34  is provided on a central region of the first land portion  11 . In this embodiment, the circumferential sub groove  34  extends in a straight manner on the tire equator C. The circumferential sub groove  34  may compress snow effectively when traveling on snowy road. Accordingly, cornering performance on snowy road can be improved. 
         [0093]    The width W 7  of the circumferential sub groove  34 , for example, is preferably in a range of from 6% to 12% the width W 6  of the first land portion  11 . The depth d 6  (shown in  FIG. 2 ) of the circumferential sub groove  34 , for example, is in a range of from 4 to 6 mm. The circumferential sub groove  34  may offer an excellent on-snow performance while ensuring rigidity of the first land portion  11 . 
         [0094]      FIG. 8  illustrates an enlarged view of the second land portion  12 . As illustrated in  FIG. 8 , the second land portion  12  is provided with a plurality of lug grooves  46  extending axially outwardly from the crown main groove  4  and terminating within the second land portion  12 , a plurality of lateral grooves  47  extending axially inwardly from the shoulder main groove  5  and terminating within the second land portion  12  and a second recess  32  provided on the edge  12   a  at the side of the crown main groove  4  of the second land portion  12 . 
         [0095]    These lug grooves  46  and lateral grooves  47  may improve on-snow performance while ensuring an excellent uneven wear resistance by maintaining the central region rigidity of the second land portion  12 . Furthermore, the second recess  32  with the crown main groove  4  may compress snow strongly when traveling on snowy road. Thus, a large snow-shearing force may be maintained and improve on-snow performance. 
         [0096]    The lug grooves  46  and the lateral grooves  47  are arranged alternately in the circumferential direction of the tire. With this, the rigidity of the second land portion  12  may be uniform, and suppress uneven wear of the second land portion  12 . 
         [0097]    In order to improve the effect described above further, the arrangement pitches L 5  of the lug grooves  46  are preferably greater than the axial width W 4  of the second land portion  12 . With this, wear resistance can further be improved. 
         [0098]    The arrangement pitches L 5  of the lug grooves  46  are preferably in a range of not less than 2.0 times, more preferably not less than 2.5 times, but preferably not more than 3.3 times, more preferably not more than 3.0 times the width W 4  of the second land portion  12 . With this, uneven wear resistance as well as on-snow performance can be improved in a well balanced manner. 
         [0099]    The lug grooves  46 , for example, are inclined with respect to the circumferential direction of the tire. The lug grooves  46  according to the embodiment, for example, are bent within the second land portion  12 . Each of the lug grooves  46 , for example, includes a first portion  14  located axially inward of a bent portion  27  and a second portion  15  located axially outward of the bent portion  27 . 
         [0100]    The angle θ 5  of the first portion  14 , for example, is in a range of from 30 to 70 degrees with respect to the circumferential direction of the tire. The second portion  15 , for example, is inclined at an angle with respect to the circumferential direction of the tire, and the angle is greater than that of the first portion  14 . These first portion  14  and second portion  15  may improve steering stability while maintaining rigidity of the central region of the second land portion  12 . 
         [0101]    Preferably, widths W 5  of the lug grooves  46  decrease gradually axially outwardly. Such lug grooves  46 , for example, may offer an excellent wear resistance while ensuring rigidity of the second land portion  12 . 
         [0102]    Lengths L 6  of the lug grooves  46  in the axial direction of the tire are preferably in a range of not less than 0.6 times, more preferably not less than 0.65 times, but preferably not more than 0.75 times, more preferably not more than 0.7 times the width W 4  of the second land portion  12 . These lug grooves  46  may improve wear resistance as well as on-snow performance in a well balance manner. 
         [0103]      FIG. 9A  illustrates a cross-sectional view of the lug groove  46  taken along a line B-B of  FIG. 8 . As illustrated in  FIG. 9A , the lug grooves  46  is preferably provided with a tie-bar  28  at the axially inner portion  16  wherein the tie-bar  28  raises its groove bottom. The tie-bar  28  may suppress uneven wear around the axially inner portion  16  of the lug grooves  46  effectively. 
         [0104]    The maximum depth d 3  of the lug grooves  46  is preferably in a range of not less than 0.55 times, more preferably not less than 0.65 times, but preferably not more than 0.8 times, more preferably not more than 0.7 times the depth d 4  of the crown main groove  4 . Such lug grooves  46  may improve wear resistance as well as on-snow performance in a well balanced manner. 
         [0105]    As illustrated in  FIG. 8 , each of the lateral grooves  47 , for example, is inclined in the same direction as the lug grooves  46 . The angle θ 6  of the lateral groove  47  is preferably in a range of not less than 30 degrees, more preferably not less than 40 degrees, but preferably not more than 70 degrees, more preferably not more than 60 degrees with respect to the circumferential direction of the tire. Such lateral grooves  47  may generate snow-shearing force in a well balanced manner in the circumferential direction of the tire as well as in the axial direction of the tire when traveling on snowy road. 
         [0106]    Each of the lateral grooves  47 , for example, includes a steep inclined portion  29  having an angle with respect to the circumferential direction of the tire wherein the angle gradually decreases axially inwardly. With this, uneven wear around the steep inclined portion  29  can be prevented. 
         [0107]      FIG. 9B  illustrates a cross-sectional view of the lateral groove  47  taken along a line C-C of  FIG. 8 . As illustrated in  FIG. 9B , the depth d 7  of the lateral groove  47 , for example, preferably increases axially outwardly. Such a steep inclined portion  29  may maintain the central region rigidity of the second land portion  12  to achieve an excellent wear resistance. 
         [0108]    The maximum depth d 8  of the lateral groove  47  is preferably in a range of not less than 0.55 times, more preferably not less than 0.65 times, but preferably not more than 0.8 times, more preferably not more than 0.7 times the depth d 5  of the shoulder main groove  5 . Such a lateral groove  47  may offer an excellent wet performance while ensuring steering stability. 
         [0109]    As illustrated in  FIG. 8 , the length L 7  of the lateral groove  47  in the axial direction of the tire is preferably in a range of not less than 0.6 times, more preferably not less than 0.65 times, more preferably not more than 0.75 times, more preferably not more than 0.7 times the axial width W 4  of the second land portion  12 . Such a lateral groove  47  may improve wear resistance and on-snow performance in a well balanced manner. 
         [0110]    In the same point of view, the circumferential distance L 8  between the axially outer end  47   o  of the lateral groove  47  and the axially outer end  46   o  of the lug groove  46  closest to the axially outer end  47   o  is preferably in a range of not less than 0.35 times, more preferably not less than 0.4 times, but preferably not more than 0.55 times, more preferably not more than 0.5 times the arrangement pitches L 5  of the lug grooves  46 . 
         [0111]      FIG. 10  illustrates an enlarged perspective view of the second recess  32 . As illustrated in  FIG. 10 , the second recess  32 , for example, includes a recess bottom surface  20  and a recess sidewall  26  extending from the recess bottom surface  20  to the ground contact surface  25  of the second land portion  12 . 
         [0112]    The recess bottom surface  20 , for example, is connected to the ground contact surface  25  of the second land portion  12 , and extends toward the bottom  32   d  of the second recess  32  while increasing the depth of the second recess  32  gradually. The recess bottom surface  20 , for example, has a substantially triangular shape having an axial width decreasing gradually from the ground contact surface toward the bottom  32   d . In this embodiment, the recess bottom surface  20  is a spherical triangle surface that protrudes radially outwardly. Such a recess bottom surface  20  may generate a large snow-shearing force by introducing snow into the second recess  32  effectively when traveling on snowy road. 
         [0113]    The recess bottom surface  20  includes a first side  21  extending on the sidewall  8  of the second land portion  12 , a second side  22  which is a boundary to the ground contact surface  25  of the second land portion  12  and a third side  23  located between the first side  21  and the second side  22 . 
         [0114]    The length of the first side  21 , for example, is preferably longer than those of the second side  22  and the third side  23 . Such a second recess  32  with the crown main groove  4  may form a large snow column to improve on-snow performance. 
         [0115]    The angle θ 7  between the first side  21  and the third side  23  is preferably in a range of not less than 10 degrees, more preferably not less than 15 degrees, but preferably not more than 30 degrees, more preferably not more than 25 degrees. When the angle θ 7  is less than 10 degrees, a sufficient volume of the second recess  32  may not be obtained. When the angle θ 7  is more than 30 degrees, the second land portion  12  may be worn easily. 
         [0116]    The angle θ 8  between the first side  21  and the second side  22  is preferably in a range of not less than 25 degrees, more preferably not less than 30 degrees, but preferably not more than 35 degrees, more preferably not more than 40 degrees. With this, when traveling on snowy road, the snow tends to be introduced into the second recess  32  easily. 
         [0117]    The second side  22 , for example, is an arc shape protruding toward the bottom  32   d  of the second recess  32 . Thus, uneven wear around the second side  22  can be prevented. 
         [0118]    The angle θ 9  between the second side  22  and the third side  23 , for example, is preferably an obtuse angle. With this, uneven wear around the vertex angle  20   t  of the recess bottom surface  20  formed between the second side  22  and the third side  23  can be prevented. 
         [0119]    The recess sidewall  26 , for example, extends radially outwardly from the third side  23  of the recess bottom surface  20  in a substantially planar shape. When traveling on snowy road, the recess sidewall  26  may compress the snow introduced in the second recess  32  axially inwardly to improve steering stability on snowy road. 
         [0120]    The depth d 9  of the second recess  32  from the ground contact surface  25  of the second land portion  12  to the bottom  32   d  of the second recess  32  is preferably in a range of not less than 0.5 times, more preferably not less than 0.6 times, but preferably not more than 0.85 times, more preferably not more than 0.75 times the depth d 4  of the crown main groove  4  (shown in  FIG. 2 ). Such a second recess  32  may improve wet performance while maintaining steering stability. 
         [0121]    As illustrated in  FIG. 8 , the circumferential distance L 9  between the bottom  32   d  of the second recess  32  and the axially inner end  46   i  of the lug groove  46  closest to the bottom  32   d  is preferably in a range of not less than 0.25 times, more preferably not less than 0.3 times, but preferably not more than 0.45 times, more preferably not more than 0.4 times the arrangement pitches L 5  of the lug grooves  46 . With this, the rigidity of an axially inner portion of the second land portion  12  may be maintained, and therefore wear resistance thereof can be maintained. 
         [0122]    The width W 8  of the second recess  32  in the axial direction is preferably in a range of not less than 0.1 times, more preferably not less than 0.15 times, but preferably not more than 0.3 times, more preferably not more than 0.25 times the axial width W 4  of the second land portion  12 . Such a second recess  32  may improve wear resistance and on-snow performance in a well balanced manner. 
         [0123]    In the same point of view, the circumferential length L 10  of the second recess  32  is preferably in a range of not less than 0.3 times, more preferably not less than 0.35 times, but preferably not more than 0.5 times, more preferably not more than 0.45 times the arrangements pitches L 5  of the lug grooves  46 . 
         [0124]    The second land portion  12  according to the embodiment, for example, is provided with a plurality of connection sipes  49  and inclined sipes  48 . Each connection sipe  49 , for example, connects between one of the second recesses  32  and one of the steep inclined portions  29  of the lateral grooves  47 . In this embodiment, the connection sipe  49  is connected to the axially inner end  29   e  of the steep inclined portion  29 . The inclined sipe  48 , for example, extends axially inwardly from the shoulder main groove  5 , and terminates within the second land portion  12 . These connection sipe  49  and inclined sipe  48  may prevent uneven wear of the second land portion  12  by uniforming the rigidity distribution of the second land portion  12 . In this description, the “sipe” means a cut having a width less than 1.0 mm, and is distinguished from a groove for draining water. 
         [0125]      FIG. 11  illustrates an enlarged view of one of the third land portions  13 . The axial width W 10  of the third land portion  13 , for example, is in a range of from 0.15 to 0.25 times the tread width TW. 
         [0126]    The third land portion  13  includes a rib region  51  and a block region  52 . The rib region  51  extends continuously in the circumferential direction of the tire. The block region  52  includes a plurality of circumferentially arranged blocks divided by a sipe and a lateral groove. 
         [0127]    The ratio W 11 /W 12  of the axial width W 11  of the rib region  51  to the axial width W 12  of the block region  52  is preferably in a range of not less than 0.2, more preferably not less than 0.23, but preferably not more than 0.3, more preferably not more than 0.27. These rib region  51  and block region  52  may improve wandering performance while maintaining steering stability. 
         [0128]    The third land portion  13  is provided with a tread edge lateral groove  53 , a longitudinal sipe  54  and a lateral sipe  55 . 
         [0129]    The tread edge lateral groove  53 , for example, extends axially inwardly from the tread edge Te, at least. Preferably, the tread edge lateral groove  53  terminates within the third land portion  13 . The tread edge lateral groove  53  according to the embodiment is curved smoothly. Such a tread edge lateral groove  53  may achieve steering stability with wandering performance. 
         [0130]    The longitudinal sipe  54 , for example, connects between the tread edge lateral grooves  53  and  53 . The longitudinal sipe  54  is connected to the axially inner ends  53   i  of the tread edge lateral grooves  53 . Such a longitudinal sipe  54  may improve cornering performance on icy road. 
         [0131]    The lateral sipe  55 , for example, is arranged between a pair of the tread edge lateral grooves  53  and  53 , and extends parallel to the tread edge lateral grooves  53 . The lateral sipe  55 , for example, extends axially inwardly from the tread edge Te at least, and terminates within the third land portion  13 . Such a lateral sipe  55  may improve wandering performance. 
         [0132]    While the embodiments in accordance with the present invention have been described in detail, the present invention is not limited to the illustrated embodiments, but can be modified and carried out in various aspects. For example, the first land portion  11  and the second land portion  12  may be arranged on both sides of a main groove except the crown main groove  4 . 
       Example 
       [0133]    Pneumatic tires having a size 225/65R17 and a basic tread pattern illustrated in  FIG. 1  were manufactured based on details shown in Table 1. For the reference example 1, a tire having the basic tread pattern illustrated in  FIG. 1  without having any recesses was manufactured. These tires were installed to the following test vehicle, and then steering stability on dry road and on-snow performance were tested. The common specification of each test tire and the test methods are as follows. 
         [0134]    Rim: 17×6.5J 
         [0135]    Tire inner pressure: 220 kPa 
         [0136]    Test vehicle: Four wheel drive vehicle with a displacement of 2,400 cc 
         [0137]    Tire installing location: All wheels 
         [0138]    Steering Stability on Dry Road: 
         [0139]    Steering stability in which the test vehicle was run on a test course of a dry asphalt road was evaluated by a driver&#39;s feeling. The results were indicated using an index based on Ref. 1 being 100. The larger the value, the better the steering stability on dry road is. 
         [0140]    On-Snow Performance: 
         [0141]    On-snow performance I which the test vehicle was run on a snowy road was evaluated by a driver&#39;s feeling. The results were indicated using an index based on Ref. 1 being 100. The larger the value, the better the on-snow performance is. 
         [0142]    The test results are shown in Table 1. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
             
             
               
                   
                 Ref. 1 
                 Ex. 1 
                 Ex. 2 
                 Ex. 3 
                 Ex. 4 
                 Ex. 5 
                 Ex. 6 
                 Ex. 7 
                 Ex. 8 
               
               
                   
               
               
                 Recess 
                 None 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
               
               
                 Recess width W1/Land portion width 
                 — 
                 0.30 
                 0.30 
                 0.20 
                 0.20 
                 0.20 
                 0.30 
                 0.60 
                 0.60 
               
               
                 W2 
               
               
                 Recess width W1/Recess length L1 
                 — 
                 0.20 
                 0.20 
                 0.20 
                 0.18 
                 0.18 
                 0.20 
                 0.20 
                 0.28 
               
               
                 Recess maximum depth d1/Main 
                 — 
                 0.60 
                 0.95 
                 0.95 
                 0.95 
                 0.95 
                 0.30 
                 0.30 
                 0.30 
               
               
                 groove depth d2 
               
               
                 Vertex angle θ1 of bottom surface of 
                 — 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
               
               
                 recess (deg.) 
               
               
                 Edge side angle θ2 of bottom surface 
                 — 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
               
               
                 of recess (deg.) 
               
               
                 Inclination angle θ3 of bottom surface 
                 — 
                 10 
                 10 
                 10 
                 10 
                 10 
                 10 
                 10 
                 10 
               
               
                 of recess (deg.) 
               
               
                 Circumferential distance between first 
                 — 
                 1.00 
                 1.00 
                 1.00 
                 1.00 
                 1.10 
                 1.00 
                 1.00 
                 1.00 
               
               
                 recess and second recess/Main 
               
               
                 groove width W1 
               
               
                 Steering stability on dry road (Score) 
                 100 
                 99 
                 96 
                 97 
                 96 
                 98 
                 100 
                 96 
                 99 
               
               
                 On-snow performance (Score) 
                 100 
                 115 
                 115 
                 109 
                 110 
                 108 
                 106 
                 110 
                 107 
               
               
                   
               
               
                   
                 Ex. 9 
                 Ex. 10 
                 Ex. 11 
                 Ex. 12 
                 Ex. 13 
                 Ex. 14 
                 Ex. 15 
                 Ex. 16 
                 Ex. 17 
               
               
                   
               
               
                 Recess 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
               
               
                 Recess width W1/Land portion width 
                 0.60 
                 0.30 
                 0.30 
                 0.30 
                 0.30 
                 0.30 
                 0.30 
                 0.30 
                 0.30 
               
               
                 W2 
               
               
                 Recess width W1/Recess length L1 
                 0.28 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
               
               
                 Recess maximum depth d1/Main 
                 0.30 
                 0.50 
                 0.65 
                 0.80 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
               
               
                 groove depth d2 
               
               
                 Vertex angle θ1 of bottom surface of 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
                 10 
               
               
                 recess (deg.) 
               
               
                 Edge side angle θ2 of bottom surface 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
               
               
                 of recess (deg.) 
               
               
                 Inclination angle θ3 of bottom surface 
                 10 
                 10 
                 10 
                 10 
                 10 
                 10 
                 10 
                 10 
                 10 
               
               
                 of recess (deg.) 
               
               
                 Circumferential distance between first 
                 0.70 
                 1.00 
                 1.00 
                 1.00 
                 0.90 
                 0.95 
                 1.05 
                 1.10 
                 1.00 
               
               
                 recess and second recess/Main 
               
               
                 groove width W1 
               
               
                 Steering stability on dry road (Score) 
                 100 
                 99 
                 99 
                 97 
                 97 
                 98 
                 99 
                 99 
                 100 
               
               
                 On-snow performance (Score) 
                 106 
                 110 
                 115 
                 115 
                 115 
                 115 
                 112 
                 113 
                 110 
               
               
                   
               
               
                   
                 Ex. 18 
                 Ex. 19 
                 Ex. 20 
                 Ex. 21 
                 Ex. 22 
                 Ex. 23 
                 Ex. 24 
                 Ex. 25 
                 Ex. 26 
               
               
                   
               
               
                 Recess 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
               
               
                 Recess width W1/Land portion width 
                 0.30 
                 0.30 
                 0.30 
                 0.30 
                 0.30 
                 0.20 
                 0.40 
                 0.30 
                 0.30 
               
               
                 W2 
               
               
                 Recess width W1/Recess length L1 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.20 
                 0.15 
                 0.25 
               
               
                 Recess maximum depth d1/Main 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
                 0.60 
               
               
                 groove depth d2 
               
               
                 Vertex angle θ1 of bottom surface of 
                 30 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
                 20 
               
               
                 recess (deg.) 
               
               
                 Edge side angle θ2 of bottom surface 
                 60 
                 50 
                 70 
                 60 
                 60 
                 60 
                 60 
                 60 
                 60 
               
               
                 of recess (deg.) 
               
               
                 Inclination angle θ3 of bottom surface 
                 10 
                 10 
                 10 
                 5 
                 15 
                 10 
                 10 
                 10 
                 10 
               
               
                 of recess (deg.) 
               
               
                 Circumferential distance between first 
                 1.00 
                 1.00 
                 1.00 
                 1.00 
                 1.00 
                 1.00 
                 1.00 
                 1.00 
                 1.00 
               
               
                 recess and second recess/Main 
               
               
                 groove width W1 
               
               
                 Steering stability on dry road (Score) 
                 98 
                 98 
                 98 
                 99 
                 97 
                 99 
                 97 
                 99 
                 98 
               
               
                 On-snow performance (Score) 
                 120 
                 114 
                 116 
                 110 
                 115 
                 111 
                 115 
                 112 
                 114 
               
               
                   
               
             
          
         
       
     
         [0143]    From the test results, it was confirmed that the example pneumatic tires shown in Table 1 have achieved steering stability on dry road with on-snow performance. 
         [0144]    Pneumatic tires having a size 225/65R17 and a basic tread pattern illustrated in  FIG. 1  were manufactured based on details shown in Table 1. For the reference example 2, a tire having the basic tread pattern illustrated in  FIG. 1  without having any second recesses was manufactured. These tires were installed to the following test vehicle, and then wear resistance performance on dry road and on-snow performance were tested. The common specification of each test tire and the test methods are as follows. 
         [0145]    Rim: 17×6.5J 
         [0146]    Tire inner pressure: 220 kPa 
         [0147]    Test vehicle: Four wheel drive vehicle with a displacement of 2,400 cc 
         [0148]    Tire installing location: All wheels 
         [0149]    Wear Resistance Performance: 
         [0150]    A wear amount of the middle land portion was measured after traveling on a test course of a dry asphalt road for a certain distance. The results were reciprocals of the wear amounts, and were indicated using an index based on Ref. 1 being 100. The larger the value, the better the wear resistance performance is. 
         [0151]    On-Snow Performance: 
         [0152]    On-snow performance in which the test vehicle was run on a snowy road was evaluated by a driver&#39;s feeling. The results were indicated using an index based on Ref. 1 being 100. The larger the value, the better the on-snow performance is. 
         [0153]    The test results are shown in Table 2. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
             
             
               
                   
                 Ref. 
                 Ex. 27 
                 Ex. 28 
                 Ex. 29 
                 Ex. 30 
                 Ex. 31 
                 Ex. 32 
                 Ex. 33 
                 Ex. 34 
               
               
                   
               
               
                 Second recess 
                 None 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
               
               
                 Lug groove arrangement 
                 2.6 
                 2.6 
                 2.6 
                 2.6 
                 2.6 
                 2.6 
                 2.6 
                 2.6 
                 2.6 
               
               
                 pitches L5/Second land 
               
               
                 portion width W4 
               
               
                 Distance between second 
                 — 
                 0.35 
                 0.5 
                 0.45 
                 0.25 
                 0.2 
                 0.35 
                 0.35 
                 0.35 
               
               
                 recess and lug groove L9/Lug 
               
               
                 groove arrangement pitches 
               
               
                 L5 
               
               
                 Distance between lug groove 
                 — 
                 0.45 
                 0.45 
                 0.45 
                 0.45 
                 0.45 
                 0.3 
                 0.35 
                 0.55 
               
               
                 and lateral groove L8/Lug 
               
               
                 groove arrangement pitches 
               
               
                 L5 
               
               
                 Connection sipe 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
               
               
                 Inclined sipe 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
               
               
                 Wear resistance performance 
                 100 
                 100 
                 98 
                 100 
                 100 
                 99 
                 98 
                 100 
                 100 
               
               
                 (Index) 
               
               
                 On-snow performance (Index) 
                 100 
                 110 
                 110 
                 110 
                 110 
                 106 
                 110 
                 110 
                 110 
               
               
                   
               
             
          
           
               
                   
                 Ex. 35 
                 Ex. 36 
                 Ex. 37 
                 Ex. 38 
                 Ex. 39 
                 Ex. 40 
                 Ex. 41 
                 Ex. 42 
               
               
                   
               
               
                 Second recess 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
               
               
                 Lug groove arrangement pitches 
                 2.6 
                 1.9 
                 2.0 
                 3.3 
                 3.4 
                 2.6 
                 2.6 
                 2.6 
               
               
                 L5/Second land portion width 
               
               
                 W4 
               
               
                 Distance between second recess 
                 0.35 
                 0.35 
                 0.35 
                 0.35 
                 0.35 
                 0.35 
                 0.35 
                 0.35 
               
               
                 and lug groove L9/Lug groove 
               
               
                 arrangement pitches L5 
               
               
                 Distance between lug groove and 
                 0.6 
                 0.45 
                 0.45 
                 0.45 
                 0.45 
                 0.45 
                 0.45 
                 0.45 
               
               
                 lateral groove L8/Lug groove 
               
               
                 arrangement pitches L5 
               
               
                 Connection sipe 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 None 
                 Presence 
                 None 
               
               
                 Inclined sipe 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 Presence 
                 None 
                 None 
                 Presence 
               
               
                 Wear resistance performance 
                 98 
                 98 
                 100 
                 100 
                 100 
                 102 
                 101 
                 101 
               
               
                 (Index) 
               
               
                 On-snow performance (Index) 
                 110 
                 110 
                 110 
                 110 
                 106 
                 107 
                 109 
                 108 
               
               
                   
               
             
          
         
       
     
         [0154]    From the test results, it was confirmed that the example pneumatic tires shown in Table 2 have improved on-snow performance while maintaining wear resistance performance.