Pneumatic tire

FIELD: transport.

SUBSTANCE: invention relates to automotive industry, namely, to studless tire tread pattern. Tire (1) tread (2) has several (5R) crown blocks (5b) separated by crosswise crown grooves (8), two rows (6R) of mid blocks (6b) separated by mid crosswise grooves (9) and two rows (7R) of shoulder blocks (7b) separated by shoulder crosswise groves (10). Every crown crosswise groove (8) is level in lengthwise direction with one crosswise crown mid groove (9) so that crosswise groove (8) is located in area (Mc) of the mid crosswise groove confined by 1st and 2nd crosswise straight lines (Za and Zb). The latter extend through 1st and 2nd extreme ends (9a, 9b) of the mid crosswise groove (9), respectively. Longitudinal length of crosswise mid groove are (Mc) makes at least 25% but not over 50% of pitch length (P) confined by 1st extreme ends (9a, 9b). Are (Mc) of mid crosswise groove does not overlap anyone shoulder crosswise groove (10).

EFFECT: better bite.

8 cl, 7 dwg, 1 tbl

 

The technical field

The present invention relates to a pneumatic tire, more particularly to the location of the transverse grooves in the tread, providing a good grip neshipovannyh tires with icy and snowy road.

The level of technology

In recent years, various kinds nelipovich tyres fitted in the area of the tread by a large number of blades, are widely used as winter tyres, suitable for driving on well-paved roads to avoid air pollution by dust.

These slats provide good traction when driving on a relatively flat and rigid pavements covered with ice and/or water film. But when driving on a road surface covered with snow to a certain depth, it becomes difficult to ensure a good grip with slats.

If the area of the grooves (especially cross grooves) in the area of the tread increases traction on snow can be improved, but the driving characteristics of the tire, such as maneuverability, traction, driving stability and the like, during the movement of the above-mentioned relatively flat and solid road surface may deteriorate.

Description of the invention

Thus, the aim of the present invention is to provide a pneumatic tire which can provide well the grip snowy road without compromising other performance tires, for example adhesion characteristics with icy road.

In accordance with the present invention a pneumatic tire comprises a tread provided on each side of the equator of the tire axially inner main groove of the crown and the axially outer main shoulder groove that run continuously in the longitudinal direction of the tire so that the tread is divided in the transverse direction on one area of the ground contact of the crown between the main grooves of the crown, the middle two of the contact area with the ground between the main grooves of the crown and shoulder main grooves and two shoulder contact area with the ground shoulder between the main grooves and the edges of the tread, where the contact area with the ground to the crown divided in the longitudinal direction of the transverse grooves of the crown with the formation of a number located in the longitudinal direction of the blocks of the crown, each of the middle areas of contact with the ground is divided in the longitudinal direction of the average transverse grooves to form the rows arranged in the longitudinal direction of the medium blocks and each shoulder contact area with the ground is divided in the longitudinal direction of the shoulder lateral grooves to form the rows arranged in the longitudinal direction of the shoulder block.

Each transverse groove of the crown is flush with the ne average transverse groove on one side and on the other side of the equator of the tire so that

above each transverse groove of the crown is within the scope of the average transverse grooves, which are limited to the aforementioned one middle lateral groove and located between the 1st and 2nd transverse straight lines that are drawn through the extreme longitudinal ends of the above-mentioned one middle lateral grooves, respectively, where

the longitudinal length of the field average transverse grooves is not less than 25%but not more than 50% of the average step length of the transverse grooves, and the length of the step is limited to the above-mentioned 1-m extreme in the longitudinal direction end and a 1-m extreme in the longitudinal direction by the end of the middle lateral grooves, following the above-mentioned 2-m extreme in the longitudinal direction of the end.

Region average transverse grooves, which are limited to the aforementioned one average transverse groove, does not overlap any of the shoulder lateral grooves formed on the same side of the equator of the tire, as mentioned above, one middle lateral groove.

Thus, each transverse groove of the crown is flush with at least one middle lateral groove in the Central region of the tread, in which the ground pressure becomes relatively high. As a result, the snow on the road surface, compacted in a cross-Kahn the internals of the crown and the average transverse groove of the crown, can form large units capable of creating large shearing force. Thus, it is possible to provide a good grip while you are driving on snow-covered roads.

Region average transverse grooves, which corresponds to the length in the longitudinal direction of the average transverse grooves, has a relatively large length in percentage from 25%to 50%. Accordingly, the longitudinal component of the average transverse grooves becomes relatively large, therefore, can be provided with a good grip on snow-covered road during rectilinear motion, as well as when driving on a curve.

Because of the shoulder lateral grooves is displaced in the longitudinal direction are located on the same level as the transverse grooves of the crown and the average transverse grooves, the shearing force of the snow from the shoulder transverse grooves can be obtained sequentially, which further enhances performance on snow.

In this application, including the following description and claims, various sizes, positions, etc. of the tire, refer to the values obtained in the normally inflated unloaded state of the tire, unless otherwise noted.

Normally inflated unloaded state is a state in which the tire is mounted on a standard rim and Naka is Jena to standard pressure, but is in an unstressed state.

Mentioned below are normally inflated loaded condition is a condition in which the tire is mounted on a standard rim, inflated to the standard pressure and loaded with a standard load for the bus.

The standard rim is a rim officially set for tire standards organizations, i.e. JATMA (Japan Association of manufacturers of automotive tyres, Japan and Asia), TRA (Technical organization rims and tyres North America), ETRTO (European technical organization rims and tyres), STRO (Scandinavian technical organization rims and tyres) and similar organizations. The standard pressure and the standard load tyres represent the maximum air pressure and the maximum load of the tire defined by the specified organizations in the table "air Pressure/maximum load" or similar list. For example, the standard rim means "standard rim" in the JATMA, the "measuring rim" in the system ETRTO, "design rim" in the TRA or the like, the Standard pressure means "maximum air pressure" in the system JATMA, the "inflation pressure" in the system ETRTO, the maximum pressure given in the table "Within loads of tyres at different pressures of the cold pumping system TRA or other Standard naked is narrow means "maximum load capacity" in the system JATMA, "carrying capacity" in the system ETRTO, the maximum value given in the above table in the system TRA, or the like, However, in the case of tires for passenger cars standard pressure and standard load tires uniformly set equal to 180 kPa and 88% of the maximum load of the tire, respectively.

The edges of The tread are axially outer edge of the contact patch with the ground (camber angle=0) in the normally inflated loaded condition.

Mentioned below width TW of the tread is a transverse distance between the edges of The tread, measured in the normally inflated unloaded state.

Brief description of drawings

Figure 1 presents a detailed partial view of the tread of the pneumatic tire in accordance with the present invention. Figure 2 presents an enlarged partial view of the tread. Figure 3 presents the cross-sectional view taken along the line A-a in figure 1.

4 shows an enlarged top view of part of a number of blocks of the crown.

Figure 5 presents an enlarged top view of part of the middle row of blocks.

Figure 6 presents an enlarged top view of part of a series of shoulder blocks.

Figure 7(a) presents a detailed partial view of the tread of the tire in comparative example 1 used in the following comparative tests.

On Phi is .7(b) presents a detailed partial view of the tread of the tire in comparative example 2, used in the following comparative tests.

Description of the preferred embodiments

Embodiments of the present invention is described in more detail below in connection with the accompanying drawings.

Pneumatic tire 1 according to the present invention includes: protector 2 with a radially outer surface defining a tread surface and the edges of The tread; a pair located at a distance in the transverse direction of the boards, each of which has a bead ring inside; a pair of side walls, passing between the edges of The tread and sides; the frame is held between the flanges through the tread and sidewall, and reinforcing the tread belt located outside of the carcass in the tread, as is well known in the technique.

In this embodiment of the pneumatic tire 1 is neshipovannyh radial tire for passenger cars.

The protector 2 is equipped with a unidirectional tread pattern, limited intended or given direction R of rotation of the tire. Given the direction R of rotation of the tire shown in side letters, labels, etc.

Unidirectional tread pattern in this embodiment, a mirror-symmetric about the equator With tires.

The protector 2, as shown in figure 1 and figure 2, provided with a main longitudinal groove 3 located on each side of the equator With the bus and held the of the present continuously in the longitudinal direction of the tire, and the main shoulder groove 4 located on each side of the equator From the tire and axially outside of the main grooves 3 of the crown, and passing continuously in the longitudinal direction of the tire.

In this embodiment, in order to ensure good drainage and characterization of spontaneous ejection of snow, the main grooves 3 of the crown and the main shoulder grooves 4 formed in the form of straight grooves parallel to the longitudinal direction of the bus.

Moreover, in order to ensure the rigidity of the blocks mentioned below, without deterioration of the characteristics of spontaneous ejection of snow, as shown in Figure 3, the transverse width W1 of the main grooves 3 of the crown ranges from 2.5 to 4.5% of the width TW of the tread and the transverse width W2 of the main shoulder of the groove 4 is from 3.0 to 5.0% of the total width TW of the tread.

Moreover, to ensure a good grip on icy road, the transverse width W1 of the main grooves 3 crown set is less than the transverse width W2 of the main shoulder of the groove 4.

If neshipovannyh tires for passenger cars, preferably as shown in Figure 3, the depth D1 of the main grooves 3 of the crown and the depth D2 of the main shoulder of the groove 4 is from 8.0 to 14.0 mm In this embodiment, the depth D1 of the groove is the same as the depth D2 of the groove (D1=D2=11,2 mm).

Thus, the protector 2 is defined following the e five areas of ground contact: region 5 soil contact crown between the main grooves 3 of the crown, two middle region 6 soil contact between the main grooves 3 of the crown and main shoulder grooves 4 and two shoulder region 7 contact with the ground located axially outside the main shoulder grooves 4.

With regard to the location of the main grooves 3 of the crown and the main shoulder grooves 4 in the transverse direction, in order to improve the balance of rigidity between the regions 5, 6 and 7 in contact with the ground and to improve the driving stability and wear resistance is preferably as shown in figure 2, the transverse distance We between the Central width of the line G1 of the main grooves 3 of the crown and the equator From the tire is not less than 4%, more preferably not less than 6%but not more than 12%, more preferably not more than 10% of the width TW of the tread, and the transverse distance Ws between the Central width of the line G2 the main shoulder of the groove 4 and the equator From the tire is not less than 26%, more preferably not less than 28%, but not more than 38%, more preferably not more than 36% of the total width TW of the tread

Region 5 soil contact crown divided in the longitudinal direction of the transverse grooves 8 of the crown with the formation of a number of 5R located in the longitudinal direction of block 5b crown, passing across the transverse width of the region 5 contact crown at ground level.

Each medium regions 6 in contact with the ground is divided in the longitudinal healthy lifestyles the Institute of middle lateral grooves 9 with the formation of a number 6R arranged in the longitudinal direction of block 6b of the crown, passing across the transverse width of the middle region 6 contact with the ground.

Each of the shoulder regions 7 in contact with the ground is divided in the longitudinal direction of the shoulder lateral grooves 10 with the formation of a number of 7R arranged in the longitudinal direction of the shoulder block 7b, passing across the transverse width of the shoulder region 7 contact with the ground.

All transverse grooves 8 of the crown in this embodiment have the same shape, as shown in Figure 4.

Each transverse groove 8 of the crown is curved relative to the direction R of rotation of the tire with the formation of the concave essentially V-shaped.

Thanks to a V-shaped transverse grooves 8 of the crown can smoothly guide the water and frozen snow between the contact area with the ground to the crown and the surface of the road, the main grooves 3 of the crown, using ground pressure, as during rectilinear movement of each transverse groove 8 of the crown into the area of contact with the ground first vertex With V-shaped and, last but not least, the transverse edges. Moreover, since the total length of the edges of the groove increases, the characteristic grip on icy roads can be improved.

In addition, in this embodiment the top With a V-shaped form is located on the equator With the tires, and the transverse groove 8 of the crown formed with metecno relative to the equator With tires. Therefore, the driving stability during straight movement and the resistance to uneven wear of the block 5b crown can be improved, as the blocks of the crown or the contact area with the ground to the crown-balanced rigidity on both sides of the equator of the tire.

The transverse groove 8 of the crown, as shown in figure 3 and Figure 4, consists of the Central part 14, which has a depth D4 and the longitudinal width W8, and a pair of side plates 15 located on each side of the Central part 14 and which has a depth D5 and the longitudinal width W7 is greater than the depth D4 and width W8, respectively (D5>D4, W7>W8).

Preferably, the depth D5 is at least 150%, more preferably at least 160%, but not more than 170%, more preferably not more than 165% of the depth D4. Through this, the characteristics of water drainage and spontaneous ejection of snow can be obtained without decreasing the hardness of the region 5 soil contact crown.

With this purpose, preferably, the depth D4 of the Central part 14 of the groove ranges from 40 to 60% of the depth D1 of the main grooves 3 of the crown. The depth D5 of the side part 15 of the groove ranges from 65 to 85% of the depth D1 of the main grooves 3 of the crown. Lateral length L1 of the Central part 14 is from 20 to 40% of the width W4 region 5 contact with the ground to the crown.

To improve the resistance to uneven wear and diversion of water, preferably the width W7 of the side part 15 of the groove on the transverse ends, facing to the main groove 3 of the crown, is not less than 1.2, more preferably not less than 1.5 but not more than 3.0, more preferably not more than 2.7 width W8 of the Central part 14 of the groove in the top (or on the equator of the tire).

The angle α1 of the Central width of the line G4 transverse grooves 8 of the crown is preferably from 50 to 80 degrees relative to the longitudinal direction. If the angle α1 is greater than 80 degrees, then the characteristic spontaneous throwing snow may deteriorate. If the angle α1 is less than 50 degrees, then the characteristic of the clutch during rectilinear motion may deteriorate.

All secondary transverse grooves 9 in this embodiment have the same shape, as shown in Figure 5.

Each secondary transverse groove 9 is curved relative to the direction R of rotation of the tire with the formation of the concave essentially V-shaped.

The average transverse groove 9 comprises an axially inner portion 9i, passing from the top With a V-shaped form to the main groove 3 of the crown with an inclination in a direction opposite to the given direction R of rotation of the tire, and the axially outer part o passing from the top With a V-shaped form to the main shoulder of the groove 4 with an inclination in a direction opposite to the given direction R of rotation of the tire.

Like transverse grooves corona, the middle lateral grooves 9 can smoothly display the snow present in the grooves in the main groove 3 of the crown and the main shoulder groove 4, using ground pressure. Moreover, thanks to the V-shape, the total length of edges average transverse grooves 9 increases, and the characteristic of the clutch with icy road can be improved.

The angle α3 of the Central width of the line G5 axially inner part 9i and angle α4 of the Central width of the line G5 axially outer part a preferably range from 65 degrees to 85 degrees relative to the longitudinal direction.

If the angles α3, α4 represent over 85 degrees, the resistance to move the snow into the main groove 3, 4 becomes larger. If the angles α3, α4 are less than 65 degrees, the characteristic of the clutch with icy road may deteriorate.

The longitudinal width of middle lateral grooves 9 increases gradually from the axially inside to the axially outer side, and in this embodiment, as shown in Figure 5, increasing speed.

Thus, the average transverse groove 9 can take water and frozen snow present in the groove, in the direction of less resistance, namely in the direction to the main shoulder of the groove 4, releasing them outside the contact patch of the tyre with the ground.

The longitudinal width of middle Poperechnaya 9 has a minimum value of W9 on the axially inner end or near it, intermediate value of W10 in the top and With a maximum value of W11 on the axially outer end or near it, and W10/W9 and attitude W11/W10 constitute not less than 1.3, preferably not less than 1.5 but not more than 3.0, preferably not more than 2.5. If the relation W10/W9 and attitude W11/W10 are greater than 3.0, medium blocks 6b may experience uneven wear. If these values are less than 1.3, the spontaneous ejection of the compacted snow from the grooves difficult.

The average transverse groove 9 provided with at least one part with an increasing width (16, 17), where the width of the middle lateral grooves 9 speed increases from the width of the narrow end portion, and at least one edge of the groove between the part with the increasing width and a narrow end part provided with a short edge cut e, e held at an angle δ of not more than 20 degrees relative to the longitudinal direction of the tire.

The total length of the edges of the groove increases, and thereby the characteristic of the clutch with icy road can be improved. Moreover, it is possible to improve the characteristic of the spontaneous ejection of snow.

In this embodiment the axially inner portion 9i provided such part 16 with increasing width, and the portion 16 with the increasing width formed axially outside end of the narrow part, and formed between the two boundary segment e.

Also, the axially outer portion a provided such part 17 with increasing width, and part 17 with increasing width formed axially outside end of the narrow part, and between them is formed of a boundary segment e.

From the point of view of the clutch characteristic with icy dear preferably at least one boundary segment e, e formed on each edge of the middle lateral grooves 9.

To speed up the drainage of water and release of snow in the direction of the main shoulder of the groove 4 is preferably as shown in Figure 3, the depth D7 axially outer part o grooves is greater than the depth D6 of the axially-inner portion 9i of the notch.

To provide rigidity to the section of the middle region 6 ground contact side of the tire equator, where the ground pressure is high, preferably the depth D6 of the axially-inner portion 9i is not more than 95%, more preferably not more than 90% of the depth D1 of the main grooves 3 of the crown.

On the other hand, if the depth D6 reduced shearing force of the snow from the road surface, compacted into the grooves may be insufficient and characterization of spontaneous throwing snow is getting worse. Therefore, preferably the depth D6 is at least 50%, more preferably at least 60% of the depth D1.

In this embodiment the depth D7 axially outer part o ka is where it is refuelled the same as the depth D1 and D2 of the main grooves 3 of the crown and the main shoulder of the groove 4. But also, the depth D7 can be excellent.

In this embodiment, the average blocks 6b is wider than the blocks 5b crown and shoulder blocks 7b. Therefore, in order to improve the drainage of water in secondary areas 6 in contact with the ground, each middle area 6 in contact with the ground supply one middle narrow groove 11, as shown in figure 2 and 5.

Middle narrow groove 11 is held directly and continuously in the longitudinal direction of the tire. Through this, each of the middle blocks 6b is divided into axially inner part 12 and the axially outer part 13.

As for the crosswise middle narrow groove 11 to balance the water drainage and the rigidity of the middle pane 6 in contact with the ground, preferably the Central width of the line G1 middle narrow groove 11 is located in the region from 30% to 60%, more preferably in the range from 40% to 50% of the width W5 medium blocks from the axially inner edge 6i medium blocks 6b in a direction axially outward.

In this embodiment the top With each average transverse groove 9 is located on the axially inner edge of the Hi average of the narrow groove 11.

Preferably, the width W3 middle narrow groove 11 is from 2.0 to 4.0 mm If the width is less than 2.0, the characteristic of spontaneous throwing snow wholeesale width is more than 4.0 mm, the rigidity of the middle pane 6 in contact with the ground (namely medium blocks 6b in General) is reduced, and the driving stability may deteriorate. For the same reasons, preferably the depth D3 (shown in figure 2) the average of the narrow groove 11 is not less than 50%, preferably at least 55%, more preferably not less than 55%but not more than 95%, preferably not more than 90%, more preferably not more than 70% of the depth D1 of the main grooves 3 of the crown.

As shown in Fig.6, the shoulder lateral grooves 10 in this embodiment are essentially straight grooves, which are essentially parallel to the transverse direction of the tire. More specifically, the angle α5 Central on the line width of the shoulder lateral grooves 10 is not more than 20 degrees relative to the transverse direction of the tire. Therefore, the shoulder blocks 7b become almost rectangular in the top view.

To get a large shearing force of the compacted snow in the shoulder regions of the tread and to avoid excessive reduction of the relations of space in the shoulder regions of the tread, preferably the width W13 of the shoulder lateral grooves 10 is not less than 7.0 mm, more preferably not less than 8.0 mm, but not more than 10.0 mm, more preferably not more than 9,0 mm And the depth D8 (shown in Figure 3) shoulder lateral grooves 10 is from 90% to 100% of the depth D2 of the main clause is iceway grooves 4.

Note that the ratio of the areas is the ratio of the real contact area to the total area (including the area of the grooves).

The number Nc of the steps of the transverse grooves 8 of the crown (i.e. the number of transverse grooves 8 of the crown in region 5 contact crown at ground level), the number Nm of steps average transverse grooves 9 (namely, the number of average transverse grooves 9 in each middle pane 5 in contact with the ground) and the number Ns of the steps of the shoulder lateral grooves 10 (namely, the number of shoulder lateral grooves 10 in each shoulder region 7 contact with the ground) is from 55 to 85.

If the number of steps is less than 55, it becomes difficult to provide a sufficient characterization of coupling with a snow-covered road, and may increase the noise moves. If the number of steps is more than 85, it becomes difficult to provide a sufficient characterization of coupling with icy road.

In this embodiment the number Nc, Nm and Ns steps are the same.

In accordance with the present invention, as shown in figures 1 and 2, the middle lateral grooves 9, located in one medium area 6 in contact with the ground (preferably in each area) are on the same level with the transverse grooves 8 of the crown in relation to the position in the longitudinal direction, so that each transverse groove 8 of the crown is in the field of MS average cross-ka is where it is refuelled.

Each area MS average transverse grooves is limited to one middle lateral groove 9 and is located between the 1st transverse straight line Za and 2nd transverse straight line Zb, held parallel to the axial direction of the tire and passing through the 1-St and 2-nd extreme in the longitudinal direction of the ends 9a and 9b of the average transverse groove 9 located on the front edge and the rear edge of the middle lateral grooves 9, respectively.

In this embodiment, the extreme longitudinal ends 9a correspond to the above-mentioned top With. Thus, each region MS average transverse grooves includes one of the transverse grooves 8 of the crown and one of the secondary transverse grooves 9, and one of the secondary transverse grooves 9 in the other middle region 6 soil contact can be added in this area Milliseconds. As a result, in the Central region of the tread 2, where the ground pressure is relatively high, two or more transverse grooves 8 and 9 are in contact with the ground simultaneously, and shearing force condensed into these grooves snow increases, therefore, you can get great traction and braking force.

In the embodiment represented in figure 1, the transverse lines Za and Zb, drawn from the extreme in the longitudinal direction of the ends 9a and 9b of one middle lateral grooves 9 average areas and 6 in contact with the ground, go through extreme in the longitudinal direction of the ends 9a and 9b of one middle lateral grooves 9 other middle pane 6 in contact with the ground.

In other words, the field of MS average transverse grooves, limited middle lateral grooves 9 one medium area 6 in contact with the ground, coincide with areas of MS average transverse grooves, limited average transverse grooves 9 other middle pane 6 in contact with the ground, respectively.

Thus, three transverse grooves 9, 8, and 9 are in the field of MS average transverse grooves.

If the average transverse grooves 9 one medium area 6 in contact with the ground is not symmetric with respect to the average transverse grooves 9 other middle pane 6 in contact with the ground, there is a possibility that one of the respective two regions MS average transverse grooves completely encloses another, and as a result, all three transverse grooves 9, 8, and 9 are present in this area.

The longitudinal length Lm of each area MS average transverse grooves is not less than 25%, preferably at least 30%, more preferably not less than 35%but not more than 50%, preferably not more than 45%, more preferably not more than 40% of the longitudinal length of the step R of average transverse grooves 9, measured between the extreme longitudinal ends 9a,as shown in figure 2. Through this, the longitudinal component of the average transverse grooves 9 increases, and the characteristic of the clutch when driving in rotation on snowy roads can be improved without deteriorating the characteristics of the clutch in straight-line motion.

As shown in figure 2, preferably mouth 8s transverse grooves 8 of the crown, facing to the main groove 3 of the crown, and the mouth 9n average transverse grooves 9 extending in the main groove 3 of the crown, at least partially overlap in the longitudinal direction of the tire.

In this embodiment mouth 9n average transverse grooves 9 is smaller in width in the longitudinal direction than the mouth 8s transverse grooves 8 of the crown, and the full width of the mouth 9n overlaps the width of the hole 8s.

When driving on snow-covered road is cross-shaped arrangement of the transverse grooves 8 of the crown, middle lateral grooves 9 and the main grooves 3 of the crown will form a dense cross-shaped lump of snow at each intersection, therefore, the shearing force of the snow increases, and the characteristic of the clutch with the snow-covered road can be further improved.

On the other hand, the shoulder lateral grooves 10 in this embodiment is displaced in the longitudinal direction relative to the transverse grooves of the crown 8 and the average transverse grooves 9.

More specifically, each transverse shoulders the first groove 10 does not overlap any region MS average transverse grooves and located between the areas of MS average transverse grooves on the same side of the equator.

Therefore, the area in the longitudinal direction, which can be obtained a large shearing force, distributed, and characterization of coupling with a snow-covered road can be further improved. To further increase the high shear snow received location on the same level as the transverse grooves of the crown and the average transverse grooves, preferably longitudinal distance L7 between the mouth 10n shoulder lateral grooves 10 extending in the main shoulder of the groove 4, and the mouth 9s middle lateral grooves 9 extending in the main shoulder of the groove 4 is not more than 10 mm, more preferably not more than 5 mm.

To improve the characteristic of the clutch with icy road, each block 5b, 6b and 7b provided with slats S and cuts K.

The slats S of each block are zigzag in the transverse direction of the tire.

Cuts To each block are mainly in the transverse direction of the tire, slightly curving towards the same longitudinal direction.

The width and depth of the incision To is from 0.1 to 2.0 mm, the Width of the slats S ranging from 0.1 to 2.0 mm, the Depth of the slats S is greater than the depth of the incision To, but less than the depth D1 and D2 of the main grooves 3 and 4. Therefore, at the initial stage of operation of the bus characteristics bus as winter neshipovannyh tires can be additional is but improved at the same time, when reaching the wear characteristics of the tread, the stability of the driving and similar characteristics of the tires, when used as a summer tire from the middle stage to the final stage of operation of the bus

As shown in figure 4, 5 and 6, relative to a given direction R of rotation of the tire cuts in the blocks 5b crown and medium-sized blocks 6b bent with the formation of the convex line. But cuts To shoulder blocks 7b bent with the formation of a concave line. Thus, it is possible to obtain the maximum edge effect under different road conditions with improved performance on icy roads.

The ratio of the areas of ET for the entire area of the tread 2 is preferably not less than 60%, more preferably at least 61%, but not more than 73%, more preferably not more than 71%.

If the ratio of the areas is NO more than 73%, the shear compacted snow reduces and characteristics on snowy roads can deteriorate. If the ratio of total area NO less than 60%, may decrease the characteristic coupling with icy road.

Comparative tests

Made studless radial tires size 265/70R16 for cars and tested as follows.

All tires have the same construction, with the exception of technical characteristics is presented in Alice 1.

Specifications common to all tires below. The width TW of the tread: 183 mm

The main groove of the crown

The width W1: 6.8 mm

The depth D1: 11,1 mm

Position Wc/TW: 9,5%

The main shoulder groove

The width W2: 7,3 mm

The depth D2: 11.2 mm

Position Ws/TW: 31,1%

Middle narrow groove

The width W3: 3.2 mm

The depth D3: 7.0 mm

Position L6/W4: 44%

Shoulder lateral groove

Width W13: 8.5 mm

Depth D8: 11.2 mm

The ratio of the areas of EM: 67%

the number of steps Nc, Nm, Ns: 68

The tread pattern is presented on Fig.7(a), the transverse grooves of the crown formed outside the regions of Central transverse groove.

The tread pattern is presented on Fig.7(b), the transverse grooves of the crown formed within regions of Central transverse groove.

Using a test car (sports car type 3500 cm3equipped with four wheels the same type of tires installed on rims size 7,0h16 and inflated to a pressure of 200 kPa)was subjected to the following tests.

Prior to testing, all the test tires were checked on a dry road surface at a distance of 100 km

Tests on snowy and icy roads

On the test car and were run on snow-covered road surface and icy road on the route and the test bus, and tires were evaluated by the sensations of driver : a test based on the handling, braking characteristics, the characteristics of traction and grip.

The results are presented in table 1 in the form of an index based on comparative example 1 taken as 100, where the higher the value, the better the response.

Test characteristics of climbing on snow-covered road

On the test car and were run on a circular route with a length of 2 kilometers, including snow rising up the road surface, the test car ran five laps and got the total time for all circles.

The inverse of the total time for all circles, are presented in table 1 in the form of an index based on comparative example 1 taken as 100, with the higher the value, the better the response.

Test characteristics of braking on icy roads

On the test car and were run on icy roads with a speed of 30 km/h, and measured brake lock all four wheels.

The inverse of the measured braking distances, are presented in table 1 in the form of an index based on comparative example 1 taken as 100, with the higher the value, the better the response.

Resistance test servname the resultant wear

On the test car and were run on a dry asphalt road surface at a distance of 3000 km and Then measured the difference between the amount of wear between the longitudinal edges of the blocks (the so-called wear front and back) for three blocks in different positions in the longitudinal direction, and the expected average value.

Average values are presented in the form of an index based on comparative example 1 taken as 100, with the higher the value, the better the resistance to uneven wear.

According to test results it is obvious that the characteristics of motion on snowy/icy roads can be significantly improved without degrading the resistance to uneven wear.

Table 1

BusSRPSRPCf. np.3Ave. 1Ave. 2SRPPRPRPRPRPRPRPRPRProverbs 11PR PR
The tread pattern (Fig.)7(a)7(b)111111111111111
Lm/P (%)3535152545553535353535353535353535
L1/W4 (%)20202020202020 40503030303030303030
W7/W81,21,21,21,21,21,21,21,21,21,21,52,53,52,02,02,02,U
W10/W81,31,31,31,31,31,31,31,31,31,31,31,31,31,31,82,23,
W11/W101,31,31,31,31,31,31,31,31,31,31,31,31,31,31,The2,23,b
Characteristics on icy roads10098102101999810010110110110099981001009997
Characteristics on snow-covered road1009598107108 106110109107110112113113112114115116
Characteristics of climbing on snow-covered road10010296105105103110110108110110112113112114114114
The braking performance on icy road1001001021019997100101101100100 99981001009998
Resistance to uneven wear1001001031029999100102102102102102100102102101100

The list of designations

2 - the protector

3 - the main groove of the crown

4 - the main shoulder groove

5 - contact area with the ground to the crown 5R - the number of blocks of the crown

6 - the average contact area with the ground 6R - average number of blocks

7 - shoulder contact area with the ground 7R - a series of shoulder blocks

8 is a transverse groove of the crown

9 - the average transverse groove

9a - 1st extreme in the longitudinal direction of the end of the middle cross

groove

9b is the 2nd least in the longitudinal direction of the end of the middle cross

groove

10 - shoulder lateral groove

With the tire equator

Me - about the region average transverse grooves

Lm - longitudinal length of the field average transverse grooves

Za - 1-I cross a straight line

Zb - 2-I cross a straight line

R - step length

The edge protector

1. A pneumatic tire (1), including:
the protector (2), provided on each side of the equator (C) tire axially inner main groove (3) of the crown and the axially outer main shoulder groove (4), which run continuously in the longitudinal direction of the tire so that the tread (2) is divided in the transverse direction on one area (5) of the ground contact of the crown between the main grooves (3) of the crown, two middle region (6) of the ground contact between the main grooves (3) of the crown and main shoulder grooves (4) and two shoulder region (7) contact with the ground between the main shoulder grooves (4) and edges (Te) of the tread, where
region (5) of the ground contact of the crown is divided in the longitudinal direction of the transverse grooves (8) of the crown with the formation of a number of (5R) located in the longitudinal direction of block (5b) crown,
each middle area (6) in contact with the ground is divided in the longitudinal direction of the middle lateral grooves (9) with the formation of a number of (6R) located in the longitudinal direction of the blocks (6b) and
each of the shoulder region (7) in contact with the ground is divided in the longitudinal direction of the shoulder lateral grooves (10) formed with the eating of a number of (7R) located in the longitudinal direction of the blocks (7b),
characterized in that
each of these transverse grooves (8) of the crown is at the same level in the longitudinal direction with one middle lateral groove (9) on one side of the equator (C) bus and the average transverse groove on the other side of the equator (C) bus so that each of the mentioned transverse groove (8) of the crown is located in the area (MS) average transverse groove, which is limited to a specified one middle lateral groove (9) and is located between the 1st and 2nd transverse straight lines (Za and Zb), which occurred within 1-St and 2-nd extreme in the longitudinal direction ends (9a) and (9b) of the said one middle lateral grooves (9), respectively,
where the longitudinal length of the field (MS) average transverse grooves is not less than 25%but not more than 50% of the length of the step (B) average transverse grooves (9)and step length (P) limited 1-m extreme in the longitudinal direction end (9a) and 1-m extreme in the longitudinal direction end (9a) of the average transverse grooves (9)that follows the specified 2-m extreme in the longitudinal direction end (9b), and
the specified region (MS) average transverse grooves, limited to the specified one middle lateral groove (9), does not overlap any of the shoulder lateral groove (10)formed on the same side of the equator (C) bus that the specified one middle lateral groove (9).

<> 2. Pneumatic tire according to claim 1, in which each of the specified transverse groove (8) of the crown corresponds to the specified one middle lateral groove (9) on each side of the equator (C) bus.

3. Pneumatic tire according to claim 1, in which the protector (2) is provided with a unidirectional tread pattern with a specified direction (R) of rotation of the tire, and with respect to the longitudinal direction corresponding to a given direction (R) of rotation of the tire, all secondary transverse groove (9) is curved with the formation of the concave essentially V-shaped.

4. Pneumatic tire according to claim 3, in which with respect to the longitudinal direction corresponding to a given direction (R) of rotation of the tire, all of the transverse grooves (8) of the crown is curved with the formation of the concave essentially V-shaped.

5. Pneumatic tire according to one of claims 1, 2, 3 or 4, in which
each of the mouths of (8s) cross grooves (8) of the crown facing in two main grooves (3) of the crown at least partially overlap in the longitudinal direction of the bus with one of the mouths of (9s) average transverse grooves (9)facing the two main grooves (3) of the crown.

6. Pneumatic tire according to claim 5, in which the mouth (9s) average transverse grooves (9), each of which enters one of the main shoulder grooves (4), do not overlap in the longitudinal direction of the bus neither one of estuaries (10n) shoulder butt is echnik grooves (10), each of which goes to the specified one of the main shoulder grooves (4), and the longitudinal distance(L7) between the mouths (9s) average transverse grooves (9) and these mouths (10n) shoulder lateral grooves (10) is not more than 20 mm.

7. Pneumatic tire according to claim 1, in which the longitudinal width of each secondary transverse grooves (9) gradually increases from the axially inside to the axially outer side of the tire.

8. Pneumatic tire according to claim 1, in which each secondary region (6) of the ground contact provided with a middle narrow groove (11)passing continuously in the longitudinal direction.



 

Same patents:

Pneumatic tire // 2524522

FIELD: transport.

SUBSTANCE: invention relates to vehicle tread pattern. Pneumatic tire (1) contains tread (2) which includes projections (23) formed by longitudinal grooves made in longitudinal direction of tire and by transversal grooves (24) crossing longitudinal grooves. The transversal grooves (24) in longitudinal direction of tire form multiple pitches (P1, P2 and P3) of tread pattern. In this structure, in the tread (2) shoulder, as tread pattern pitch decreases the volume ratio of transversal grooves (24) in the volume of portion corresponding to tread pattern pitch increases, and in the central zone of tread (2), as tread pattern pitch decreases the volume ratio of transversal grooves in the volume of portion corresponding to tread pattern pitch decreases.

EFFECT: higher stability of vehicle driving while keeping tread uniformity.

4 cl, 5 dwg

FIELD: transport.

SUBSTANCE: tire tread has at least two wearing plies including outer wearing ply and at least one inner wearing ply located at mid tread under outer wearing ply, and at least one outer groove located in outer wearing ply. Besides, said tread features volumetric cavity ratio of 0.25-0.40 in sound state and of about 0.25-0.40 in worn-out state. External side interacting with ground extends along one of inner wearing ply in worn-out tread. Additionally, said tread features contact surface ratio of 0.66-0.72 in sound state and of about 0.56-0.66 in worn-out state.

EFFECT: enhanced performances.

15 cl, 19 dwg

Pneumatic tire // 2521052

FIELD: transport.

SUBSTANCE: invention relates to tread pattern of automobile non-spiked tire with improved noise characteristics. Pneumatic tire includes axially-internal lengthwise rows of crown blocks which rows are located at each side of tire equator, and axially-external lengthwise rows of shoulder blocks which rows are located axially to the outside of axially-internal lengthwise rows. Crown blocks are longitudinally separated by the first and the second interleaving transverse grooves of the crown. Shoulder blocks are longitudinally separated by the first and the second interleaving transverse shoulder grooves. The first transverse shoulder grooves have width of not less than 3.5 mm. The first transverse crown grooves have width of not less than 2.0 mm. The second transverse shoulder grooves include axially-internal slit-shaped portion with width of 0.5 to 2.0 mm and axially-external main portion at least 3.5 mm wide. The second transverse crown grooves include axially-internal slit-shaped portion with width of 0.5 to 2.0 mm and axially-external main portion at least 2.0 mm wide.

EFFECT: better tire noise characteristics without impairment of running characteristics over snow-covered road surface.

9 cl, 5 dwg, 1 tbl

Pneumatic tire // 2520265

FIELD: machine building.

SUBSTANCE: proposed tire comprises tread zone (A) located from vehicle inner side and tread zone (B) located on vehicle outer side. There are multiple slot-like drain grooves (32A, 32B) extending over tire width and formed in every block (31A, 31B). The number of blocks (31A) in said zone (A) is larger than that of blocks (31B) in said zone (B). Note here that slot-like drain grooves (32B) in blocks (31B) of zone (B) are configured to extend linearly along their depth. Note here that slot-like drain grooves (32A) in blocks (31A) of zone (A) are configured to extend in wavy manner along their depth.

EFFECT: better road grip on dry road and snow.

7 cl, 4 dwg

Pneumatic tire // 2519327

FIELD: transport.

SUBSTANCE: method is executed by means of making multiple wave-shaped grooves (20) in central belt (16) of tread between two ring grooves (14) located with tilt relative to equatorial plane of tire and consisting of central small elements (26) equatorial plane CL and side small elements (28) at two sides of this equatorial plane. In each of side small elements (28), the second transversal groove (40) is made containing wide area (42) and narrow area (44). Reducing fragmentation of rubber and cracking in side small elements (28) is achieved due to formation of area (54) with raised bottom on periphery of the first acute-angled area (50) and formation of the first bevelled area (56A) on sharp end of the first acute-angled area (50).

EFFECT: lower noise level, rubber fragmentation and cracking in tread elements, higher dewatering capability.

4 cl, 3 tbl, 13 dwg

FIELD: transport.

SUBSTANCE: tread contains multiple grooved obstructing elements (4) which are formed by and located in circular grooves (2). Herewith, obstructing elements (4) go from bottom (21) of circular groove (2) and blocks at least 70% of cross-section area of circular groove (2). Bending parameter of grooved obstructing elements (4) is determined as E·I/(h3l), where E is module at 10% elongation of material used for grooved obstructing elements, I is inertia moment of grooved obstructing element cross-section, h is height of grooved obstructing element, and l is width of grooved obstructing element, and ranges from 250 Pa to 350 Pa.

EFFECT: providing grooved obstructing elements wear to degree equivalent to tread section wear degree while reducing noise caused by resonance of air columns and maintaining retraction characteristics.

6 cl, 6 dwg, 1 tbl

Pneumatic tire // 2513210

FIELD: transport.

SUBSTANCE: invention relates to tread pattern of tire designed to be used on dry road, ice- and snow-covered roads. Proposed tire comprises unidirectional tread pattern including right and left lengthwise grooves of the crown and crow rib arranged there between. Crown rib has first and second V-like grooves arranged by turns in the tire lengthwise direction. First V-like grooves extend from the left lengthwise groove of the crown. Second V-like grooves extend from the right lengthwise groove of the crown. First and second V-like grooves terminate nearby the rib while their V-like configurations have inflections located, in fact, at tire equator.

EFFECT: stable motion on dry road, ice- and snow-covered roads.

9 cl, 10 dwg, 1 tbl

FIELD: transport.

SUBSTANCE: invention relates to automotive industry, namely, to tread pattern. Tire features tread asymmetric patter wherein ratio of actual area of contact to total area for zone 2o of outer side is larger than that for inner side zone 2i but with minor difference characteristic of water removal for right and left wheel tires. Said tire has tread surface 2 divided by four lengthwise grooves 3 and 4 into central area 5 of contact with soil, mid areas 6,6 of contact with soil and shoulder areas 7,7 of contact with soil. Said mid area 6o and shoulder area 7o in outer side zone 2o are divided by outer mid transverse grooves 8o and outer shoulder transverse grooves 10o into blocks 9o and blocks 11o. Mid transverse grooves 8o are inclined in opposite direction to inclination of shoulder transverse grooves 10o relative to tire axial direction while transverse grooves 8o and 10o are inclined at angle θmo of 5-45° and at angle θso over 0° and not over 40°, respectively.

EFFECT: better stability in rainy and dry weather.

8 cl, 6 dwg, 1 tbl

FIELD: transport.

SUBSTANCE: tread comprises multiple raised elements 10 confined by cutouts. At least one of said raised elements 10 has dents 2 of maximum depth H not larger than tread thickness. This dent is located in major direction confined by the dent track ends on new tread and in minor direction extending in tread depth. Dent 2 has first part 21 and second part 22. Dent first part 21 extends in minor direction between contact side 15 in new state and depth H1 equal to, at least, 40% of maximum depth H while second part 22 extends the first part 21 in tread depth. Note here that said second part 22 extends to depth H2. Dent second part 22 in major direction has at least one first section 221 and one second section 222.

EFFECT: improved performances.

10 cl, 7 dwg

FIELD: transport.

SUBSTANCE: tread 2 has rounded shoulders and is divided by the main lengthwise grooves 3 and crosswise grooves 4 in blocks 5 furnished with pockets 6, each having zigzag part 8. Lengthwise grooves 3 include at least two axially outer lengthwise grooves 3o dividing the tread 2 into shoulders Ysh and crowns Ycr wherein zigzag part 8 of pockets 6sh in shoulders Ysh features larger zigzag amplitude Wsh and larger zigzag pitch Psh that zigzag amplitude Wcr and zigzag pitch Wcr of zigzag part 8 of pockets 6cr in crowns Ycr. Inclination angle θsh of pockets 6sh relative to axial direction is smaller than angle θcr.

EFFECT: improved flotation at dry road at minimum deterioration of performances on snow-covered road.

7 cl, 7 dwg, 1 tbl

Pneumatic tire // 2523539

FIELD: transport.

SUBSTANCE: pneumatic tire 1 having excellent snow-running characteristics while keeping control stability and resistance to uneven wear, including tread 2 containing a pair of longitudinal crown grooves running continuously in longitudinal direction of tire at both sides of tire equator C and having edges, where one edge 3m runs in zigzag fashion, so that L-shaped sections 3s of groove edge are continuously interconnected in tire longitudinal direction, and the other edge 3n runs in corrugated manner so that arc-shaped sections of groove edge 3o having arc-shaped convexity towards groove centre are continuously interconnected in tire longitudinal direction where each section 3s of L-shaped groove edge includes long portion 3c inclined at angle of 1 to 20° relative to longitudinal direction, and short portion 3t with longitudinal length less than this value for long portion 3c and inclined in direction opposite to direction of the mentioned long portion 3c relative to longitudinal direction.

EFFECT: improved characteristics.

17 cl, 1 tbl, 10 dwg

FIELD: transport.

SUBSTANCE: tire tread has at least two wearing plies including outer wearing ply and at least one inner wearing ply located at mid tread under outer wearing ply, and at least one outer groove located in outer wearing ply. Besides, said tread features volumetric cavity ratio of 0.25-0.40 in sound state and of about 0.25-0.40 in worn-out state. External side interacting with ground extends along one of inner wearing ply in worn-out tread. Additionally, said tread features contact surface ratio of 0.66-0.72 in sound state and of about 0.56-0.66 in worn-out state.

EFFECT: enhanced performances.

15 cl, 19 dwg

Pneumatic tire // 2521052

FIELD: transport.

SUBSTANCE: invention relates to tread pattern of automobile non-spiked tire with improved noise characteristics. Pneumatic tire includes axially-internal lengthwise rows of crown blocks which rows are located at each side of tire equator, and axially-external lengthwise rows of shoulder blocks which rows are located axially to the outside of axially-internal lengthwise rows. Crown blocks are longitudinally separated by the first and the second interleaving transverse grooves of the crown. Shoulder blocks are longitudinally separated by the first and the second interleaving transverse shoulder grooves. The first transverse shoulder grooves have width of not less than 3.5 mm. The first transverse crown grooves have width of not less than 2.0 mm. The second transverse shoulder grooves include axially-internal slit-shaped portion with width of 0.5 to 2.0 mm and axially-external main portion at least 3.5 mm wide. The second transverse crown grooves include axially-internal slit-shaped portion with width of 0.5 to 2.0 mm and axially-external main portion at least 2.0 mm wide.

EFFECT: better tire noise characteristics without impairment of running characteristics over snow-covered road surface.

9 cl, 5 dwg, 1 tbl

Automotive tire // 2521033

FIELD: transport.

SUBSTANCE: invention relates to automotive winter tire tread design. Tire (1) has tread (2) containing central part (L1) covering from two sides the equatorial plane (7), and two shoulder parts. The central part (L1) is separated from shoulder parts (L2, L3) of tread by two first circumferential grooves (3, 6). At least two second circumferential grooves (4, 5) are located in the central part (L1). The second circumferential grooves (4, 5) determine margins of the central circumferential bar (10) containing multiple sipes (20) located in parallel to each other and at certain distance from each other. The second circumferential grooves (4, 5) have a mid line running as peak-to-valley scallops throughout tire length in direction along circumference. The mid lines with peak-to-valley scallops are mainly matching in phase with each other throughout tire length (1) in direction along circumference.

EFFECT: better operational properties when moving both over snowy and dry and wet road surfaces.

20 cl, 4 dwg, 1 tbl

Pneumatic tire // 2520265

FIELD: machine building.

SUBSTANCE: proposed tire comprises tread zone (A) located from vehicle inner side and tread zone (B) located on vehicle outer side. There are multiple slot-like drain grooves (32A, 32B) extending over tire width and formed in every block (31A, 31B). The number of blocks (31A) in said zone (A) is larger than that of blocks (31B) in said zone (B). Note here that slot-like drain grooves (32B) in blocks (31B) of zone (B) are configured to extend linearly along their depth. Note here that slot-like drain grooves (32A) in blocks (31A) of zone (A) are configured to extend in wavy manner along their depth.

EFFECT: better road grip on dry road and snow.

7 cl, 4 dwg

Pneumatic tire // 2520265

FIELD: machine building.

SUBSTANCE: proposed tire comprises tread zone (A) located from vehicle inner side and tread zone (B) located on vehicle outer side. There are multiple slot-like drain grooves (32A, 32B) extending over tire width and formed in every block (31A, 31B). The number of blocks (31A) in said zone (A) is larger than that of blocks (31B) in said zone (B). Note here that slot-like drain grooves (32B) in blocks (31B) of zone (B) are configured to extend linearly along their depth. Note here that slot-like drain grooves (32A) in blocks (31A) of zone (A) are configured to extend in wavy manner along their depth.

EFFECT: better road grip on dry road and snow.

7 cl, 4 dwg

Pneumatic tire // 2519327

FIELD: transport.

SUBSTANCE: method is executed by means of making multiple wave-shaped grooves (20) in central belt (16) of tread between two ring grooves (14) located with tilt relative to equatorial plane of tire and consisting of central small elements (26) equatorial plane CL and side small elements (28) at two sides of this equatorial plane. In each of side small elements (28), the second transversal groove (40) is made containing wide area (42) and narrow area (44). Reducing fragmentation of rubber and cracking in side small elements (28) is achieved due to formation of area (54) with raised bottom on periphery of the first acute-angled area (50) and formation of the first bevelled area (56A) on sharp end of the first acute-angled area (50).

EFFECT: lower noise level, rubber fragmentation and cracking in tread elements, higher dewatering capability.

4 cl, 3 tbl, 13 dwg

Pneumatic tire // 2508996

FIELD: transport.

SUBSTANCE: invention relates to automotive industry, namely, to tread pattern. Proposed tire comprises multiple circular main grooves extending in tire circumference and multiple running surfaces separated and composed by said circular main grooves in tread zone. Multiple running sections have multiple sipes. At least 90% of sipes located in inner side area represent are 2D sipes and at least 90% of sipes in outer side surface are 3D sipes. Tread zone comprises top and bottom rubber layers. Rubber hardness H1in at -10°C and rubber hardness H2in at 20°C of rubber top layer 151in in inner side area, and hardness H1out at -10°C and hardness H2out at 20°C of rubber top layer 151out in outer side area are related by relationships H1in<H1out and H2in<H2out.

EFFECT: better stability on dry and snowy surface.

18 cl, 9 dwg

Pneumatic tire // 2508995

FIELD: transport.

SUBSTANCE: invention relates to automotive industry, namely, to tread pattern. Tire tread has circular major grooves extending in tire circumference and contact parts separated and composed on said circular major grooves. Every said central zone contact part and contact parts of right and left shoulder zone has multiple sipes. At least 90% of sipes located in inner side area represent are 2D sipes in central zone and at leas 90% of sipes in outer side surface are 3D sipes in shoulder zone. Every contact parts of right and left shoulder zones has multiple transverse side grooves arranged in definite order in tire circumference. The number N-ce of transverse side grooves in central zone contact part and the number N-sh of transverse side grooves in contact parts of right and left shoulder zones are relates as N-ce>N-sh.

EFFECT: perfected design.

20 cl, 7 dwg

FIELD: transport.

SUBSTANCE: invention relates to automotive industry, namely, to tread pattern. Tire features tread asymmetric patter wherein ratio of actual area of contact to total area for zone 2o of outer side is larger than that for inner side zone 2i but with minor difference characteristic of water removal for right and left wheel tires. Said tire has tread surface 2 divided by four lengthwise grooves 3 and 4 into central area 5 of contact with soil, mid areas 6,6 of contact with soil and shoulder areas 7,7 of contact with soil. Said mid area 6o and shoulder area 7o in outer side zone 2o are divided by outer mid transverse grooves 8o and outer shoulder transverse grooves 10o into blocks 9o and blocks 11o. Mid transverse grooves 8o are inclined in opposite direction to inclination of shoulder transverse grooves 10o relative to tire axial direction while transverse grooves 8o and 10o are inclined at angle θmo of 5-45° and at angle θso over 0° and not over 40°, respectively.

EFFECT: better stability in rainy and dry weather.

8 cl, 6 dwg, 1 tbl

Pneumatic tire // 2524522

FIELD: transport.

SUBSTANCE: invention relates to vehicle tread pattern. Pneumatic tire (1) contains tread (2) which includes projections (23) formed by longitudinal grooves made in longitudinal direction of tire and by transversal grooves (24) crossing longitudinal grooves. The transversal grooves (24) in longitudinal direction of tire form multiple pitches (P1, P2 and P3) of tread pattern. In this structure, in the tread (2) shoulder, as tread pattern pitch decreases the volume ratio of transversal grooves (24) in the volume of portion corresponding to tread pattern pitch increases, and in the central zone of tread (2), as tread pattern pitch decreases the volume ratio of transversal grooves in the volume of portion corresponding to tread pattern pitch decreases.

EFFECT: higher stability of vehicle driving while keeping tread uniformity.

4 cl, 5 dwg

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