KR100593008B1 - Heavy duty Pneumatic Radial Tire - Google Patents

Abstract

The present invention is applied to the circumferential direction of the tire (running direction) and formed in the center longitudinal groove of the tread, the shoulder longitudinal groove formed in the shoulder portion of the tread, and the center-shoulder formed between the center longitudinal groove and the shoulder longitudinal groove. A longitudinal groove, a center transverse groove applied in the tread width direction of the tire and formed at the center portion of the tread, a shoulder transverse groove formed at the shoulder portion of the tread, and a center-shoulder transverse groove formed between the center transverse groove and the shoulder transverse groove And a center block formed by the groove and formed at the center of the tread, a shoulder block formed at the shoulder of the tread, and a center-shoulder block formed between the center block and the shoulder block. In heavy-duty pneumatic radial tires having a tread pattern, the upper part of the longitudinal groove is in the tread width direction. Is formed to be straight, in the longitudinal groove bottom is made in a zigzag form by 5 ~ 7 ° to the tire running direction, it characterized in that the width of the bottom of the longitudinal groove are formed narrower than the top width of the longitudinal groove.

Blocks, Grooves, Blocking Stones, Sipes

Description

Heavy Duty Pneumatic Radial Tires             

1 is a view showing a pneumatic radial tire for a heavy load according to the present invention.

2 is a plan view showing a pattern of a pneumatic radial tire for a heavy load according to an embodiment of the present invention.

3A is a plan view illustrating in detail the longitudinal groove shown in FIG. 2.

FIG. 3B is a sectional view taken along line A′-A of FIG. 2, ie, a longitudinal groove not including a break prevention tool.

FIG. 3C is a cross-sectional view taken along line B-B of FIG.

FIG. 3D is a cross-sectional view taken along the line C-C of FIG.

<Description of Symbols for Main Parts of Drawings>

C / L: Tire circumferential center line RS: Rim diameter line

10: inner liner rubber layer 20: carcass cord layer

30: tread rubber layer 40: belt cord layer

1: Stone jam prevention tool (stone eject bar) 2: Saipe

W1: Width of crushing prevention tool H1: Height of crushing prevention tool

B1: Center Block B2: Center-Shoulder Block

B3: shoulder block GW1: center bell groove

GW2: center-shoulder longitudinal groove GW3: shoulder longitudinal groove

GW4: Center Lateral Groove GW5: Center-Shoulder Lateral Groove

GW6: Shoulder Transverse Groove

TW: Tread Width Tc: Tread Width Centerline

ASD: depth of longitudinal groove ASD1: depth of horizontal groove

SP1, SP2: Sipe length P: Long groove 1 pitch

Ga: longitudinal groove top width Gb: longitudinal groove bottom width

Groove Top Line (GTL): Vertical Groove Top Line

GBL (Groove Bottom Line): Long Groove Bottom Line

GTCL (Groove Top Center Line): Long Groove Top Center Line

GBCL (Groove Bottom Center Line): Long groove bottom center line

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heavy-duty pneumatic radial tire, which effectively suppresses wear and tear such as heel and toe wear between tire blocks, improves braking properties, and prevents segregation by crushing during unpacking driving. The present invention relates to a pneumatic radial tire for a heavy load which improves the service life of a tire.

In the case of a conventional heavy-load radial pneumatic tire, various types of block patterns are designed to improve traction performance.

For example, as in our current 943W pattern, the lateral groove is designed to have a wider interval between blocks and perpendicular to the driving direction to improve traction.

However, the conventional heavy-loaded radial pneumatic tires have a high heel and toe wear, resulting in premature wear of the tires, as well as reduced ride comfort and separation of tires due to crushing during unpacking. A phenomenon (separation) occurred.

The present invention has been made to solve the above problems, the purpose of which is to effectively suppress the wear and tear, such as heel and toy (HEEL AND TOE) wear between the tire blocks, to improve the braking performance, to the crushing during unpacking driving The present invention provides a heavy-load pneumatic radial tire that prevents separation by improving tire durability.

In order to achieve the above object, the present invention is applied to the circumferential direction (driving direction) of the tire, the center longitudinal groove formed on the center portion of the tread, the shoulder longitudinal groove formed on the shoulder portion of the tread, the center longitudinal groove and the shoulder A center-shoulder longitudinal groove formed between the longitudinal grooves, a center horizontal groove applied in the tread width direction of the tire and formed at the center portion of the tread, a shoulder horizontal groove formed at the shoulder portion of the tread, and the center horizontal groove and the shoulder side groove A center-shoulder transverse groove formed therebetween, a center block defined by the groove and formed at the center portion of the tread, a shoulder block formed at the shoulder portion of the tread, and a center-shoulder block formed between the center block and the shoulder block. In a heavy-duty pneumatic radial tire having a straight six-ribbed tread pattern comprising The upper part of the lube is formed perpendicular to the tread width direction, and the lower part of the longitudinal groove is formed in a zigzag shape at 5 to 7 ° with respect to the tire driving direction, and the width of the lower part of the longitudinal groove is narrower than the upper width of the longitudinal groove. It is characterized by.

In the above, when the lower portion of the longitudinal groove is formed in a zigzag form less than 5 ° with respect to the tire driving direction, there is a problem in that the late abrasion traction performance decreases, and the lower portion of the longitudinal groove exceeds 7 ° with respect to the tire driving direction. If it is made of traction performance is improved, but the problem of decay emission is generated.

The width of the vertical groove is preferably 0.045 to 0.055 times the width of the tread, and the depth of the longitudinal groove is preferably 0.8 to 1.2 times the width of the vertical groove.

If the width of the upper part of the groove is less than 0.045 times the width of the tread, the occurrence of crushing in the groove increases, causing a problem of damage to the belt. After that, the problem of faster wear occurs.

In addition, when the depth of the longitudinal groove is less than 0.8 times the upper width of the longitudinal groove, the mileage is reduced, and when the depth of the longitudinal groove exceeds 1.2 times the upper width of the longitudinal groove, cracks in the groove and cracks are generated under the groove.
The angle of inclination of the longitudinal groove (the inclination inclined upward from the bottom of the longitudinal groove to the side of the block with respect to the radial direction of the tire) is at most 15 to 20 ° and at least 4 to 7 °. It is preferable that the angle is made within the range of.
When the inclination angle of the longitudinal groove is less than 15 °, the problem that the pinching is increased, the inclination angle of the longitudinal groove is a problem that the traction performance is lowered when the top angle exceeds 20 °.

In addition, the inclination angle of the longitudinal groove is a problem that the crushing is increased when the minimum angle is less than 4 °, the angular angle of the longitudinal groove is a problem that the traction performance is reduced when the minimum angle exceeds 7 °.

delete

delete

The present invention is characterized in that the lower portion of the longitudinal groove is formed with a plurality of anti-twist tool in the shape of the longitudinal groove.

The interval between the pinch prevention openings is preferably 1/32 to 1/8 of 1 pitch of longitudinal grooves, and more preferably 1/16 of 1 pitch of longitudinal grooves.

The length of the anti-jamming tool is preferably 1/8 to 1/3 of the pitch of longitudinal grooves, more preferably 1/8.

In the above, when the spacing between the anti-knuckles is less than 1/32 of the pitch of the longitudinal groove, a problem occurs that the end-of-wear traction performance decreases. The problem that the belt is damaged due to the occurrence of crushing occurs.

In addition, when the length of the anti-twisting tool is less than 1/8 of the pitch of one longitudinal groove, a problem occurs in that the belt is damaged due to the twisting, and when the length of the anti-twisting tool exceeds one third of the longitudinal groove, wear occurs. There is a problem that the terminal traction performance is reduced.

It is preferable that the width of the anti-twisting tool is 0.15 to 0.25 times the width of the vertical groove, and the height of the anti-twisting tool is 0.2 to 0.3 times the depth of the longitudinal groove.

In the above, if the width of the anti-knock hole is less than 0.15 times the upper width of the longitudinal groove, not only does not prevent the anti-tilt, but also the belt is damaged. There is a crack underneath.

In addition, if the height of the anti-twisting tool is less than 0.2 times the depth of the longitudinal groove, not only does not prevent the proper function of anti-twisting, but also damages the belt. At the end of the day, traction performance drops.

The present invention is characterized in that the depth of the horizontal groove is 0.2 ~ 0.3 times the depth of the longitudinal groove, the width of the horizontal groove is 0.15 ~ 0.25 times the upper width of the longitudinal groove.

In the above, when the depth of the lateral groove is less than 0.2 times the depth of the longitudinal groove, the traction performance is reduced, and when the depth of the lateral groove exceeds 0.3 times the depth of the longitudinal groove, premature wear of the solder part occurs.

In addition, when the width of the lateral groove is less than 0.15 times the upper width of the longitudinal groove, the problem that the initial traction is reduced, and when the width of the lateral groove exceeds 0.25 times the upper width of the longitudinal groove, wear resistance performance is reduced Is generated.

In addition, the distance between the center longitudinal groove and the center-shoulder longitudinal groove is 0.14 to 0.18 times the tread width, and the distance between the center longitudinal groove and the shoulder longitudinal groove is preferably 0.30 to 0.34 times the tread width.

If the distance between the center longitudinal groove and the center-shoulder longitudinal groove is less than 0.14 times the tread width, the center block is prematurely worn, and if the distance between the center longitudinal groove and the center-shoulder longitudinal groove exceeds 0.18 times the tread width, the center -There is a problem that the shoulder block is prematurely worn.

In addition, when the distance between the center longitudinal groove and the shoulder longitudinal groove is less than 0.30 times the tread width, a problem arises that the center-shoulder block is prematurely worn, and the distance between the center longitudinal groove and the shoulder longitudinal groove is 0.34 times the tread width. If exceeded, the shoulder block is prematurely worn.

The present invention is characterized in that the sipe is applied to both sides of the block in the tread width direction.

The sipes are preferably applied at 30 to 50 per pitch of longitudinal grooves, and more preferably at least 40 said sipes per pitch of longitudinal grooves.

In the above, when the sipes are applied less than 30 per pitch of longitudinal grooves, premature wear around the grooves is generated, and when the sipes are applied more than 50 per pitch of the longitudinal grooves, tearing of the grooves is generated when crushing occurs.

It is preferable that the length of the said sipe is 3-6 mm.

When the length of the sipe is less than 3mm in the above, there is almost no effect that the early wear around the groove is improved, and when the length of the sipe exceeds 6mm, groove tearing due to pinching occurs.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing a heavy-load pneumatic radial tire according to the present invention, Figure 2 is a plan view showing a pattern of a heavy-load pneumatic radial tire according to an embodiment of the present invention.

1 and 2, the heavy-loaded pneumatic radial tire of the present invention is a rubber layer attached to the inside of the tire, the inner liner rubber layer 10 for preventing cord protection and water absorption, and loads the cord layer inside the tire. A carcass cord layer (also known as a 'body ply') 20 that is supportive, shock-resistant, and resistant to flexion during driving, and a tread rubber layer that is in direct contact with the road surface (30) ), A belt cord layer 40 between the tread rubber layer 30 and the carcass cord layer 20.

The tread pattern of the heavy duty pneumatic radial tire according to the present invention is a straight six-ribbed type.

Here, "straight six-ribbed" means that six blocks are partitioned by five grooves as shown in FIGS. 2 and 3, and the overall shape of the blocks and grooves is formed in a straight line in the tire driving direction. Say.

Looking at the tire pattern having the 'straight six-ribbed' in more detail, it consists of a longitudinal groove applied in the running direction of the tire, a lateral groove applied in the tread width direction of the tire, and blocks partitioned by the groove.

The longitudinal groove includes a center longitudinal groove (GW1) formed at the center portion of the tread, a shoulder longitudinal groove (GW3) formed at the shoulder portion of the tread, and a center-shoulder longitudinal groove (GW2) formed between the center longitudinal groove and the shoulder longitudinal groove. There is).

The horizontal groove includes a center horizontal groove (GW4) formed at the center portion of the tread, a shoulder horizontal groove (GW6) formed at the shoulder portion of the tread, and a center-shoulder horizontal groove (GW5) formed between the center horizontal groove and the shoulder horizontal groove. There is).

The block includes a center block B1 formed at the center of the tread, a shoulder block B3 formed at the shoulder of the tread, and a center-shoulder block B2 formed between the center block and the shoulder block.

In addition, the interval between the center longitudinal groove (GW1) and the center-shoulder longitudinal groove (GW2) is 0.14 ~ 0.18 times the tread width (TW), the interval between the center longitudinal groove (GW1) and shoulder longitudinal groove (GW3) is tread width It is preferable that it is 0.30 to 0.34 times (TW).

In the above, when the distance between the center longitudinal groove (GW1) and the center-shoulder longitudinal groove (GW2) is less than 0.14 times the tread width (TW), premature wear of the center block (B1) occurs, and the center longitudinal groove (GW1) and the center If the distance between the shoulder longitudinal grooves GW2 exceeds 0.18 times the tread width TW, the center-shoulder block B2 may be prematurely worn.

In addition, if the distance between the center longitudinal groove (GW1) and the shoulder longitudinal groove (GW3) is less than 0.30 times the tread width (TW), the problem that the center-shoulder block (B2) is early wear occurs, the center longitudinal groove If the distance between GW1 and the shoulder longitudinal groove GW3 exceeds 0.34 times the tread width TW, the problem occurs that the shoulder block B3 becomes prematurely worn.

The present invention is characterized in that the sipes 2 are applied to both sides of the blocks B1, B2, and B3 in the tread width TW direction.

The sipes 2 are preferably 30 to 50 per pitch P of longitudinal grooves, and more preferably 40 of the sipes 2 per pitch P of longitudinal grooves.

In the above, when the sipes 2 are applied at less than 30 per pitch P of the longitudinal groove, premature wear around the groove occurs, and the sipes 2 are greater than 50 per pitch P of the longitudinal groove. If it is applied, the groove tearing phenomenon occurs when crushing occurs.

It is preferable that the length SP1 and SP2 of the said sipe 2 are 3-6 mm.

In the above, when the length SP2 of the sipe 2 is less than 3 mm, there is a problem that the effect of early wear improvement around the groove is hardly generated. When the length SP1 of the sipe 2 exceeds 6 mm, the grooves are formed by crushing. Tearing occurs.

Next, the specifications of the longitudinal grooves GW1, GW2 and GW3 will be described in more detail with reference to FIGS. 3A to 3C.

3A is a plan view illustrating the longitudinal groove shown in FIG. 2 in more detail, and FIG. 3B is a sectional view taken along the line A′-A of FIG. 3C is a cross-sectional view taken along the line B-B of FIG. 2, that is, the longitudinal groove including the pinch block.

In the present invention, the specifications of the center longitudinal groove GW1, the center-shoulder longitudinal groove GW2 and the shoulder longitudinal groove GW3 are preferably the same.

The longitudinal grooves GW1, GW2 and GW3 according to the present invention have different top and bottom shapes. That is, as shown in Figure 3a, the upper part of the longitudinal grooves (GW1) (GW2) (GW3) has a vertical shape (straight in the running direction of the tire) (GTL) and the tread width direction (TW) of the tire The lower part of the longitudinal grooves GW1, GW2 and GW3 has a zigzag shape GBL in the tire traveling direction.

In other words, an upper portion of the longitudinal grooves GW1, GW2, and GW3 is formed along a center of a tread width centerline (also referred to as a 'longitudinal groove upper centerline') GTCL, and the longitudinal groove GW1. Lower portions of GW2 and GW3 are formed along the longitudinal groove lower centerline GBCL.

The lower portion of the longitudinal groove is preferably formed in a zigzag with an angle AG3 of 5 to 7 ° with respect to the traveling direction of the tire, that is, the longitudinal groove upper center line GTCL.

Reference numeral Gb is the width of the longitudinal groove bottom.

In the above, when the lower portion of the longitudinal groove is formed in a zigzag form of less than 5 ° with respect to the tire driving direction, there is a problem in that the wear and tear traction performance decreases, and the lower portion of the longitudinal groove has a zigzag form in excess of 7 ° with respect to the tire driving direction. If it is made of traction performance is improved, but the problem of decay emission is generated.

Accordingly, in the present invention, the sizes of the inclination angles AG2 and AG1 on the longitudinal groove A side (highest inclination) and the longitudinal groove A 'side (lowest inclination) are different.

Here, the 'inclined angle' refers to the angle inclined from the bottom of the longitudinal groove to the top relative to the tire radius direction.
The inclination of the longitudinal groove is made of left and right sides, and since the lower portion of the longitudinal groove is formed in a zigzag, the inclination angle is changed within a predetermined angle.

That is, the relationship between the inclination angle AG2 of the A side of the longitudinal groove and the inclination angle AG1 of the A 'side of the longitudinal groove is that in the case of the A-A' cross section, the inclination angle AG2 of the A side represents the highest inclination angle, The inclination angle AG1 on the A 'side indicates the lowest inclination angle.
The inclination angles AG1 and AG2 formed on the left and right sides of the lower longitudinal grooves are formed along the longitudinal grooves, and are formed from the A side inclination angle to the A 'side inclination angle and gradually change from the A side inclination angle to the A' side inclination angle. The change from the side inclination angle to the A side inclination angle is repeated.

It is preferable that the inclination angle AG2 on the longitudinal groove A side is 15 to 20 degrees, and the inclination angle AG1 on the longitudinal groove A 'side is 4 to 7 degrees.

If the inclination angle AG2 of the longitudinal groove A side is less than 15 °, the problem of increase in crushing occurs. If the inclination angle AG2 of the longitudinal groove A side exceeds 20 °, the problem of lowering the traction performance occurs.

In addition, when the inclination angle AG1 of the longitudinal groove A 'side is less than 4 °, a problem occurs in which the turning increases, and when the inclination angle AG1 of the longitudinal groove A' side exceeds 7 °, the traction performance decreases. Is generated.

In the present invention, it is preferable that the width Ga of the upper part of the longitudinal groove is 0.045 to 0.055 times the width of the tread, and the depth ASD of the longitudinal groove is 0.8 to 1.2 times the width of the upper part of the longitudinal groove.

In the above, when the width Ga of the upper part of the longitudinal groove is less than 0.045 times the tread width TW, the occurrence of crushing in the groove increases, causing the belt to be damaged, and the width Ga of the upper part of the longitudinal groove is defined as the tread width ( If it exceeds 0.055 times of TW), the traction is good, but a problem arises that abrasion becomes fast.

In addition, if the depth ASD of the longitudinal groove is less than 0.8 times the upper width Ga of the longitudinal groove, the mileage decreases. Crushing in the grooves and cracks under the grooves.

According to the present invention, by applying the longitudinal grooves GW1, GW2, and GW3 having the above-described structure (including specifications) to the tread part, separation due to crushing during unpacking driving can be prevented, thereby improving tire durability. .

3A and 3C, the lower part of the longitudinal groove is characterized in that a plurality of anti-twisting tools 1 are formed in the longitudinal groove shape.

The interval between the pinch stops 1 is preferably 1/32 to 1/8 of the longitudinal groove 1 pitch P, more preferably 1/16 of the longitudinal groove 1 pitch P.

The length of the anti-jamming tool 1 is preferably 1/8 to 1/3 of the longitudinal groove 1 pitch P, and more preferably 1/8.

If the spacing between the anti-knuckle (1) is less than 1/32 of the longitudinal groove 1 pitch (P) is a problem that the end-of-wear traction performance is reduced, the spacing between the anti-knuckle (1) is longitudinal groove 1 If it exceeds 1/8 of the pitch P, the belt may be damaged by the occurrence of crushing in the gap.

In addition, if the length of the anti-twisting tool 1 is less than 1/8 of the longitudinal groove 1 pitch P, the belt due to curling is damaged, and the length of the anti-twisting tool 1 is equal to the longitudinal groove 1 pitch ( If 1/3 is exceeded, the end-wear traction performance is deteriorated.

It is preferable that the width W1 of the anti-jamming tool is 0.15 to 0.25 times the upper width Ga of the vertical groove, and the height H1 of the anti-chipping tool is 0.2 to 0.3 times the longitudinal groove depth ASD.

If the width W1 of the anti-twisting tool is less than 0.15 times the upper width Ga of the vertical groove, not only does not prevent the anti-twisting function but also the belt is damaged, and the width W1 of the anti-twisting tool is the upper end of the vertical groove. Exceeding 0.25 times the width Ga causes a problem that a crack is generated under the groove.

In addition, if the height (H1) of the anti-twisting tool is less than 0.2 times the depth of the longitudinal groove depth (ASD) not only does not properly serve to prevent the face crushing, the belt is damaged, and the height (H1) of the chucking stop Exceeding 0.3 times the groove depth ASD causes a problem in that the traction performance decreases at the end of wear.

As described above, by forming a squeeze-preventing hole in the longitudinal groove, it is possible to prevent crushing in the center longitudinal groove during unpaved driving, thereby preventing separation of the tread.

Next, with reference to Figure 3d, the specification of the horizontal groove of the present invention will be described.

FIG. 3D is a cross-sectional view taken along the line C-C of FIG.

As shown in Figure 3d, the present invention has a depth (ASD1) of the horizontal groove is 0.2 to 0.3 times the longitudinal groove depth (ASD), the width of the horizontal groove (GW4) (GW5) (GW6) is the top of the longitudinal groove It is characterized in that 0.15 ~ 0.25 times the width (Ga).

In the above, if the depth ASD1 of the horizontal groove is less than 0.2 times of the longitudinal groove depth ASD, the traction performance decreases, and when the depth ASD1 of the lateral groove exceeds 0.3 times the longitudinal groove depth ASD, wear is rapid. There is a problem going forward.

In addition, when the width of the horizontal groove is less than 0.15 times the upper width Ga of the longitudinal groove, the initial traction performance is reduced, and when the width of the horizontal groove exceeds 0.25 times the upper width Ga of the longitudinal groove, the wear resistance is reduced. The problem of poor performance is caused.

 The present invention made as described above, effectively suppresses the wear and tear, such as heel and toe (HEEL AND TOE) wear between the tire blocks without deteriorating other performance, and improves the braking property, and prevents the segregation by the crushing during unpacking driving can do.

Accordingly, the present invention can improve the durability life of the tire.

Claims (8)

A center longitudinal groove applied in the circumferential direction of the tire and formed at the center portion of the tread; a shoulder longitudinal groove formed at the shoulder portion of the tread; and a center-shoulder longitudinal groove formed between the center longitudinal groove and the shoulder longitudinal groove; A center transverse groove formed in the tread width direction of the tire and formed at the center portion of the tread, a shoulder transverse groove formed at the shoulder portion of the tread, and a center shoulder transverse groove formed between the center transverse groove and the shoulder transverse groove A straight six-ribbed tread pattern comprising a center block defined by a groove and formed at the center of the tread, a shoulder block formed at the shoulder of the tread, and a center-shoulder block formed between the center block and the shoulder block. In the pneumatic radial tire for the branch, The upper part of the longitudinal groove is formed perpendicular to the tread width direction, and the lower part of the longitudinal groove is formed in a zigzag shape with 5 to 7 ° with respect to the tire driving direction, and the width of the lower part of the longitudinal groove is narrower than the upper width of the longitudinal groove. Pneumatic radial tire for heavy loads, characterized in that. The heavy-duty pneumatic radial tire according to claim 1, wherein the width of the longitudinal groove is 0.045 to 0.055 times the width of the tread, and the depth of the longitudinal groove is 0.8 to 1.2 times the width of the longitudinal groove. According to claim 1, wherein the left and right inclination angle formed from the bottom of the longitudinal groove to the top is formed in the range between the highest angle and the lowest angle based on the radial direction of the tire, the maximum angle is 15 ~ 20 °, Pneumatic radial tire for heavy loads, characterized in that the minimum angle is 4 ~ 7 °. The method of claim 1, wherein the bottom of the bell groove is formed in the form of a plurality of anti-knuckle in the groove, the interval between the anti-knuckle is 1/32 ~ 1/8 of the pitch 1 longitudinal groove, the stone pinch A pneumatic radial tire for heavy loads, characterized in that the length of the guard is 1/8 to 1/3 of the pitch of one longitudinal groove. 5. The heavy-duty pneumatic radial tire according to claim 4, wherein the width of the anti-twisting tool is 0.15 to 0.25 times the width of the longitudinal groove, and the height of the chuck is 0.2 to 0.3 times the depth of the longitudinal groove. The heavy-duty pneumatic radial tire according to claim 1, wherein the depth of the horizontal groove is 0.2 to 0.3 times the depth of the longitudinal groove, and the width of the horizontal groove is 0.15 to 0.25 times the upper width of the longitudinal groove. The heavy load air according to claim 1, wherein the distance between the center longitudinal groove and the center-shoulder longitudinal groove is 0.14 to 0.18 times the tread width, and the distance between the center longitudinal groove and the shoulder longitudinal groove is 0.30 to 0.34 times the tread width. Mouth radial tires. The method according to any one of claims 1 to 7, wherein a sipe is applied to both sides of the block in the tread width direction, wherein the sipes are 30 to 50 per pitch of longitudinal grooves, and the length of the sipes is 3 to 6 mm. A heavy duty pneumatic radial tire characterized by the above-mentioned.

Images