Pneumatic tire

FIELD: transport.

SUBSTANCE: invention relates to automotive industry, namely, to tread pattern. Group GB of small blocks is arranged on, at least, a section of tire running surface 1. Group of small blocks comprises multiple small blocks 3 located side by side. Said group comprises, at least, one lengthwise main groove designed by position 4 including through section of said groove extending linearly along running surface and, at least, one ribbed lateral section 6 adjoining lengthwise main groove to make side surface 5 of said groove extending continuously in longitudinal direction. Density D of small blocks varies from 0.003 to 0.04 pc/mm2 to express amount of said block per actual area of contact spot.

EFFECT: better water removal, ruled out irregular wear, better running on ice and snow.

4 cl, 7 dwg, 2 tbl

 

The technical field to which the invention relates.

The present invention relates to pneumatic tires with checkers on a Jogging area formed by the grooves. In particular, the present invention proposes a technology for improving the parameters for drainage while preventing uneven wear and greatly improving the running performance on ice/snow.

Description of the appropriate level of technology

In conventional pneumatic tires, such as the one shown in figure 4, checkers 103, as a rule, are formed longitudinal grooves 101, passing in the longitudinal direction of the treadmill, as well as the transverse grooves 102, passing in the transverse direction of the treadmill, in addition, to improve the running performance on ice and increased edge effect, checkers made slit drainage grooves. In addition, such a pneumatic tire, due to requirements for increased demands on the chassis, brake indicators and indicators when driving in rotation, as the number of slit drainage grooves 104 in checkers 103 is increased, and the improvement of running performance on ice is achieved by increasing the area of the contact spot, the number of pieces is reduced to 3-9, and each piece 103 has an elongated shape in the circumferential direction Jogging layer, as disclosed in Japanese published vannoy patent publication No. 2002-192914.

Summary of the invention

Problems, the solution of which the invention is directed

Unfortunately, as in conventional pneumatic tires, discussed above, the width of each portion 103A checkers, separated by narrow drainage grooves 104 increases, the stiffness of the divided parts of checkers becomes insufficient. As a result of this divided part 103A checkers are deformed upon contact with the road surface and grip with the road surface deteriorates. In result, it becomes difficult to achieve high running performance when driving on ice, necessary for modern cars. In addition, since the size of each checkers 103 increases, when braking is not possible to completely remove the water film formed between the ice and the bus from the Central part checkers 103 by means of mere slit drainage grooves 104. This is another factor hindering the improvement of running performance on ice. In addition, although on the one hand, it is advisable to reduce the negative coefficient (i.e. the ratio between the surface area of the contact spot and the total area of the contact spot, including grooves) by increasing the contact area between the treadmill and the road surface to improve the running performance on ice, on the other hand, it is advisable zoom is to the negative coefficient by increasing the area of the grooves, thus, these indicators are mutually exclusive.

Accordingly, the present invention is directed to solving the above problems, and its objective is to improve the properties of the drainage system, preventing uneven wear, as well as significant improvement of running performance when driving on ice/snow due to the optimization of the tread pattern.

Tools for problem solving

To achieve the above objectives the present invention proposes a pneumatic tire with a small group of checkers, located at least on the part of the Jogging station, a group of small checkers includes many small pieces, which are located next to each other, each of the small checkers formed grooves, many checkers lined up in a row and pass in the longitudinal direction, the bus contains:

at least one longitudinal main groove, passing through a group of small pieces, the longitudinal main groove made in the form of through-plot linearly passing in the longitudinal direction of the treadmill;

at least one ribbed cross section, located adjacent to the longitudinal main groove, the ridge section forms a side surface of the longitudinal main groove and continuously runs in the longitudinal direction; and

the numerical platnost the D small checkers is in the range of 0.003 to 0.04 (pieces/mm 2), numerical density, D is the number of small checkers unit actual area of the contact spot of the group of small grooves and is calculated by the formula: D=a/{PL×W×(1-N/100)-S}, where

PL (mm) represents a small step checkers 3 in group GB,

W (mm) represents the width of GB(equal to the width TW of the contact spot of the treadmill, as this variant implementation checkers 3 are located around the Jogging section 1),

while (PCs) denotes the number of pieces 3, located in the computational domain Z (hatched area in the drawing) of GBlimited by the length of the pitch PL and width W,

N (%) indicates a negative factor in the computational domain Z,

S (mm2) denotes the surface area of the ribbed cross-country area, located in the computational domain.

It should be noted that the term "estimated step length small pieces" in this case refers to the minimum unit of a repeating pattern of small pieces in this range, checkers, forming a group of small pieces. For example, if a repeating pattern is formed of one small piece and groove forming this small piece, characterized by the step length is small checkers is calculated by adding the length of his checkers in the longitudinal direction of the treadmill with the length in the longitudinal direction of the treadmill one Cana is key, adjacent to such a small piece in the longitudinal direction of the treadmill. In addition, the term "width of a small group of checkers" refers to the width of a group of small pieces, which is formed by the arrangement of small checkers so that they were next to each other in the transverse direction of the treadmill. For example, if the group is small checkers passes across the treadmill, the width of a small group of checkers refers to the width of the contact spot of the treadmill. The term "actual contact area is" a small group of checkers refers to the total surface of all the small pieces, placed in the computational domain of a small group of checkers. In other words, the actual contact area refers to the area obtained by subtracting the area of the grooves, respectively, forming small pieces, the square of the longitudinal main groove, and the surface area of the finned cross-country plot of the square computational domain, which is obtained by multiplying the characteristic length PL of the step width W. in Addition, the term "surface area of the finned Jogging area" refers to the total surface area of the finned cross-country areas in the computational domain. It should be noted that the term "small piece" in this case does not include "ribbed cross section" kakato becomes clear from the above formula. That is, when counting the number of small checkers quantity ribbed cross-country areas in the calculation. In addition, the actual contact area is small checkers does not include the contact area (i.e. surface area) ribbed cross-country section.

In the pneumatic tire of the present invention, because the small pieces are arranged so that they are placed next to each other, it is possible to increase the total edge length of the sticks, which can improve the edge effect in comparison with a variant that uses a slit-like drainage grooves. In addition, since the surface area of each of the small checkers is much smaller than in conventional checkers, it is possible to improve the coupling properties of each draughts, and you can reduce the distance from the Central region to the peripheral region checkers for effective removal of water film from the Central zone checkers. In addition, the water in the contact patch effectively play through the longitudinal main groove, in which there is a through section of the groove. In addition, since the running of land located near the longitudinal main groove has the shape of a rib, it is possible to ensure sufficient rigidity, which can prevent the uneven wear small checkers around the longitudinal main groove.

Thus, since the pneumatic tire according to the present invention due to the above properties, through the use of small checkers has excellent coupling properties and the boundary effect, it effectively removes the water layer, and by using a ribbed cross-country site provides effective drainage of water through the longitudinal main groove and prevents uneven wear, this can improve performance for the removal of water while preventing uneven wear, and significantly improve the running performance on ice/snow.

Preferably, on the ribbed area were narrow grooves and narrow grooves are closed at the contact of the ribbed cross-country area with the road.

In addition, it is preferable that the width of the narrow grooves is in the range of from 0.2 to 2.0 mm

In addition, it is preferable that the side wall is adjacent to the longitudinal main groove, passed linearly in the longitudinal direction of the treadmill.

The technical result

Pneumatic tire according to the present invention allows to improve drainage while preventing uneven wear, and significantly improve the running performance on ice/snow due to the optimization of the tread pattern.

Brief description of drawings

Figure 1 shows a portion of the a rule drawing tread pneumatic tyres (tires in example 1) according to one of the embodiments of the present invention.

Figure 2 shows a partial drawing of the tread pneumatic tyres (tires in example 2) in another variant implementation of the present invention.

Figure 3 shows a partial drawing of the tread pneumatic tyres (tires in example 3) in another variant implementation of the present invention.

Figure 4 shows a partial drawing of the tread conventional pneumatic tyres (standard tyres 1).

Figure 5 shows a partially theoretical drawing of the tread comparative pneumatic tyres (tires comparative Sample 1).

Figure 6 shows a partial drawing of the tread comparative pneumatic tyres (tires comparative Sample 2).

7 shows a partial drawing of the tread comparative pneumatic tyres (tires comparative Sample 3).

The implementation of the invention

Further embodiments of the present invention will be described with reference to the drawings. 1 shows a tread pattern of a pneumatic tire (hereinafter "bus") in one of the embodiments of the present invention. It should be noted that in the drawing the vertical direction is the longitudinal direction and the horizontal direction (the direction perpendicular to the Equatorial plane E) is the transverse direction of the treadmill.

Although this is e shown in the drawing, the bus on this version of the implementation is of the usual construction, consisting of a skeleton, toroidal passing between a pair of left and right cores sides of the tire cord that is located radially outside the crown area above the frame in the radial direction of the tire, and plot the treadmill, which is located radially outside the cord. Plot treadmill tire has a tread pattern shown in figure 1.

As shown in figure 1, to the race site 1 tyres have a group GBconsisting of many small checkers 3, each of which is formed adjacent grooves 2. In this variant implementation of GBcheckers are all running site 1. All pieces are arranged in a zigzag manner in the longitudinal direction.

Preferably to the outer surface of each of the small checkers 3 had the shape of a polygon, in this case the octagon. That is, small pieces 3 have the shape of a column with a cross section in the form of a plate. It is preferable that the height of the small checkers 3 ranged from 60 to 100% of the depth of the longitudinal main grooves 4, more preferably from 70 to 90% of the depth of the longitudinal main groove 4.

The size of each of the small checkers 3 is smaller than checkers conventional tread pattern shown in figure 4, and the density n is large draughts 3 above, than conventional tread pattern shown in figure 4. The smaller the size of each of the small checkers 3 and the higher density small checkers 3, the more pronounced edge effect and better drainage, the preferred range specified below. That is, the numerical density D small checkers (PCs/mm2) is the number of small checkers unit actual area of contact group GB small grooves and is calculated by the formula

and is in the range of 0.003 to 0.04 (pieces/mm2), where

PL (mm) represents a small step checkers 3 in group GB,

W (mm) represents the width of GB(equal to the width TW of the contact spot of the treadmill, as this variant implementation checkers 3 are located around the Jogging section 1),

a (PCs) denotes the number of pieces 3, located in the computational domain Z (hatched area in the drawing) of GBlimited by the length of the pitch PL and width W,

N (%) indicates a negative factor in the computational domain Z,

S (mm2) denotes the surface area of the ribbed cross-country area, located in the computational domain.

Numerical density D indicates how many small checkers 3 falls on a unit area (mm2section where you will find small pieces. The actual square is the contact spot is the area excluding ribbed cross-country land and grooves. Solely as an example, the normal winter tyres density D below about 0.002. It should be noted that when calculating the number "and" checkers 3, located in the computational domain Z of GBif some small pieces 3 are both inside and outside the computational domain Z of GBand cannot be counted as a checker, the number of small checkers 3 is calculated as the ratio of the remaining small square checkers 3 in a characteristic area to the surface area of such checkers 3. For example, as in the case of checkers, indicated by the position B1 in figure 1, which is both inside and outside the specific region Z, and only half of which is characteristic of the range of Z, it can be counted as 1/2 checkers.

If the density D checkers 3 in group GBis less than 0.003 (pieces/mm2), to achieve a high edge effect without the use of slit drainage grooves will be difficult. If the density D of the small checkers 3 is more than 0.04 (pieces/mm2), the size of each small pieces 3 becomes too small to provide the necessary rigidity checkers. In addition, if the density D of the small checkers 3 in group GBis in the range from 0.0035 to 0.03 (PCs/mm2), it is possible to simultaneously provide both rigidity checkers 3 and edge effect at higher indices.

In addition, the tire has at least one (in this variant implementation) of the longitudinal main groove 4, passing through the GBcheckers and containing a through portion which passes linearly in the longitudinal direction of the treadmill. The longitudinal main groove 4 is located in the Central part of the treadmill (in the Equatorial plane). The longitudinal main groove 4 passes through the GBsmall grooves. In this variant implementation, because of GBlocated throughout the Jogging section 1, of the longitudinal main groove 4 runs along the entire circumference.

In addition, in the circumferential direction of the tire has a pair of ribbed cross-country sections 6, which are located near at least one of the sides (both sides in this variant implementation) longitudinal main grooves, forming at least one of the surfaces (both surfaces of the grooves in this variant implementation) of the longitudinal main groove 4. The side wall (i.e., the surface 5 of the groove) ribbed Jogging area 6 adjacent to the longitudinal main groove 4, is held in the circumferential direction. Thus, the width W1the groove is of constant width clearance in the area where the GB.

In the bus on this variant implementation accounts for the arrangement of checkers 3 in close proximity to each other, coupling properties of the road surface treadmill improved in particular improve the braking performance and the rolling of the rear wheels in the front track. Although conventional bus driving performance on ice is improved through the use of a certain number of slit drainage grooves in relatively large blocks, the improvement of running performance on ice is limited to this technology, since the divided areas of checkers between slit drainage grooves to bend upon contact with the road surface, which complicates the creation of a uniform adhesion. In turn, since the present invention a certain number of small checkers 3 are located next to each other so that the density D of the small checkers is within the specified range, this allows to achieve a higher marginal effect compared to winter tires with narrow drainage grooves.

In addition, because the regular bus configuration slit drainage grooves are located in relatively large blocks, removing a water film with a plot icy surface corresponding to the Central part of the surface of checkers, is difficult. In turn, the present invention can effectively remove the water film due to the fact that the surface area of the small checkers 3 small, and the distance from the Central part to the peripheral part of the surface is tis little pieces.

Although it is possible to radically improve the running performance on ice by the arrangement of small sticks in the immediate vicinity of each other, greatly increasing the actual contact patch, this configuration leads to the fact that the treadmill becomes as smooth tires. Moreover, it hinders the drainage on wet roads. Therefore, due to the fact that according to the present invention in the group GBcheckers has a longitudinal groove 4 through segment passing linearly in the circumferential direction of the treadmill, it becomes possible to effectively drain water away from the surface of the contact spot through the longitudinal main groove 4. This can further improve the running performance on ice due to the synergy effect with small pieces 3. In addition, the longitudinal main groove 4 improves various aspects of running performance on snow, in particular the indicators when driving in rotation on ice and snow by increasing edge effect in the lateral direction. Width W1the grooves may vary depending on the required indicators for water drainage, etc.

However, if for improvements in the drainage system used longitudinal main groove 4, the load will be in checkers 3 located around (from the side) of the longitudinal main grooves 4 and small Sha the Cam will have to carry the load instead of the longitudinal main groove. The result is that by concentrating the load increases the wear small checkers 3. To prevent this, the present invention Jogging area, adjacent to the longitudinal main groove 4 has a ribbed shape provides the rigidity of this Jogging area that helps prevent uneven wear.

Thus, due to the aforementioned features of the pneumatic tire according to the present invention has excellent coupling properties and the boundary effect, enables the effective removal of water film with a small checkers 3, located next to each other, the effective removal of water by means of the longitudinal main grooves 4, and prevents uneven wear due to the ribbed section 6, thereby improving the properties of the drainage and preventing uneven wear, while significantly improving the running performance on ice/snow.

Although the ribbed section 6 allows to provide the above effect, even if the ribbed section 6 is located only on one side of the longitudinal main grooves 4, preferably, if the running performance on ice and wet road surface are important to the length of the ribbed section 6 has been reduced, but instead used small blocks 3 placed around the ditches and 2. On the other hand, if it is important to prevent uneven wear, preferably ribbed to Jogging areas 6 were located on both sides of the longitudinal main groove 4. Besides, ribbed cross-country area located adjacent to the longitudinal main groove 4, provides a more uniform drainage along the longitudinal main groove 4, thereby further contributing to the improvement of the parameters of the drainage, as well as to increase the rigidity of checkers, located around the longitudinal main groove 4, thereby improving handling on dry and wet pavement.

In addition, in the tire according to this variant implementation of the side wall (side surface 5 of the longitudinal main grooves) ribbed cross-country plot 6 passes linearly in the longitudinal direction of the running surface, due to which all parts of the longitudinal main grooves act as a cross-cutting area, which further improves the drainage of the longitudinal main groove 4.

In addition, in the tire according to this variant implementation of small pieces 3 are arranged zigzag, which can further increase the number of small checkers 3, the edges of which are consistently used in the rotation of the tire, additionally increasing, thus, the edge effect. In addition, when sigs loobraznoy the location of the small checkers 3 time of entering into contact with the road surface at the adjacent checkers 3, located in the transverse direction of the treadmill can be varied, thereby reducing the noise figure. In addition, when the zig-zag arrangement of the small checkers 3, as noted above, you can easily increase the density of small checkers 3. Also, if small pieces 3 are arranged zigzag, with the increased density of D small pieces, adjacent small pieces 3 will support each other when exposed to a high load to a small checkers 3, which can further increase the rigidity of the small checkers 3 and to improve the running performance on ice.

Next will be described other embodiments of the present invention. Figure 2 presents part of the drawing, which shows a tread pattern of a pneumatic tire according to another variant implementation of the present invention.

As shown in figure 2, to the race site 1 such tires are of GBsmall pieces, consisting of many small checkers 3, each of which is formed by passing near it grooves 2. Of GBsmall checkers are held throughout the Jogging section 1. All small pieces are arranged zigzag in the longitudinal direction of the treadmill. The cross section of each of the small checkers 3 has the shape of an octagon. That is, small pieces 3 have the form of octagonal columns. The number of the n density D small checkers is from 0.003 to 0.04 (pieces/mm 2).

In addition, the group GBcheckers has at least one (in this variant implementation) of the longitudinal main groove 4, passing in the longitudinal direction of the treadmill. Also has a pair of ribbed cross-country sections 6, adjacent at least one side (both sides in this variant implementation) longitudinal main grooves 4, which form at least one of the side surfaces (both surfaces of the grooves in this variant implementation) longitudinal main grooves 4 and are continuously in the longitudinal direction. The side wall (i.e., the surface 5 of the groove) ribbed Jogging area 6 adjacent to the longitudinal main groove 4, passes linearly in the longitudinal direction. Thus, the width W1the groove is constant in the field of GBsmall grooves.

Under this option the implementation of slit drainage grooves 7, which in the absence of contact with the road surface is disclosed on the running surface and can impinge upon contact with the road surface, and during rotation, is made in the form of narrow grooves. Can be used slit drainage grooves 7 of any shape, provided that they can be gathered after the tire is mounted on a corresponding rim, Naka is Ana to correct pressure, on the bus affects the corresponding load and the tire rotates.

In this case, the above-mentioned corresponding rim" refers to the rim, determined in accordance with the standard for tires of each type, for example "Standard rim" in JATMA (manufacturers Association the Japan automobile tire), "design rim" in TRA (Association of tires and wheels) or "Control ring" ETRTO (European technical organization for tire and rim). Above "the appropriate pressure refers to the pressure that is set in accordance with the above standards for tires of each type, for example "Maximum pressure" in JATMA, the maximum value listed in "Maximum permissible load for cold tyres at different pressure" or "tire Pressure" in ETRTO. Above "the appropriate load refers to the load in accordance with the above standards for tires of each type, for example "Maximum load capacity" in JATMA, the maximum value listed in "Maximum permissible load for cold tyres at different pressure" or "Permissible load" ETRTO.

Under this option the implementation of the reduction of small checkers 3 (i.e., reducing edges) resulting from the use of longitudinal main grooves 4 and ribbed cross-country section 6 may be more the but slit drainage grooves 7, which further improves driving performance on ice/snow, the rate of water drainage and prevents uneven wear. It should be noted that the present invention it is preferable that the width of slit drainage grooves 7, located on the ribbed section 6, was in the range of from 0.2 to 2.0 mm This is because if the width of the grooves 7 will be less than 0.2 mm, the edge effect may be insufficient, and if the width is more than 2.0 mm, the rigidity ribbed Jogging area will decrease, which will hinder effective prevention of uneven wear.

Next will be considered another variant of implementation of the present invention. Figure 3 presents part of the drawing, which shows a tread pattern of a pneumatic tire according to another variant implementation of the present invention.

As shown in figure 2, to the race site 1 such tires have a group GBsmall pieces, consisting of many small checkers 3, each of which is formed by passing near it grooves 2. Of GBsmall checkers are held throughout the Jogging section 1. All small pieces are arranged zigzag in the longitudinal direction of the treadmill. The cross section of each of the small checkers 3 has the shape of an octagon. That is, small pieces 3 are views of vos is migranal columns. Numerical density D small checkers is from 0.003 to 0.04 (pieces/mm2).

In addition, the group GBsmall checkers, there are two longitudinal main grooves 4, linearly passing in the longitudinal direction of the treadmill. Although longitudinal main grooves 4 are located on both sides of the equator S of the tire, such longitudinal main grooves 4 are asymmetric relative to the equator S of the tire. That is, the distance X1longitudinal main grooves 4 on the left from the equator side in the drawing is less than the distance X2longitudinal main grooves 4 on the right from the equator side. In addition, although the side walls 5 of each of the longitudinal main grooves 4 are composed of only one of the straight part, the width of each of the grooves is different from each other. That is, the width W1longitudinal main grooves 4 on the left is greater than width W2longitudinal main grooves 4 on the right. Therefore, the tread pattern shown in figure 4, is asymmetric.

In addition, the groups GBsmall checkers are ribbed cross-country sections 6, each ribbed section 6 is located near one side of each longitudinal main grooves 4 and continuously runs in the longitudinal direction of the treadmill, forming one of the side walls 5 of the groove of each of the longitudinal main grooves 4. As in the variant implemented the program of figure 2, in each of the ribbed cross-country sections 6 are slit drainage grooves.

In the bus on this version of the exercise by increasing the number of longitudinal main grooves 4 can strengthen their scraping effect in the lateral direction (transverse direction), thereby improving performance when driving in rotation on ice/snow. In addition to this longitudinal main grooves 4)where there are no small pieces 3, distributed, which can provide uniform coupling properties with the road surface and be improved running performance on ice/snow. In addition, due to the position of the longitudinal main grooves 4 asymmetrically on the left and right sides, a longitudinal main grooves 4 can be positioned in such a way as to ensure maximum drainage and improved running performance on snow, which can effectively improve both the parameter data. For example, because of the negative axial curvature or similar phenomena, if the width of the longitudinal main groove 4 located on the inner side from the center of the treadmill in the axial direction is increased (see figure 3), the parameters for the drainage can be improved.

The more the width of the longitudinal main grooves 4, the better the drainage. Meanwhile, when the increase in the number of wide longitudinal key to navok 4 there is the possibility of high-frequency noise of the tires. Therefore, it is preferable that the longitudinal main groove 4 large width was placed in such a way as to ensure the best performance for the drainage, and the width of the other of the longitudinal main grooves 4 was small to prevent high-frequency noise of the tires.

Although the present invention is described with reference to several variants of its implementation, according to the present invention it is preferable that the negative coefficient N in a group GBsmall checkers were in the range from 5% to 50%. If negative coefficient N is less than 5%, then the area of the grooves will be insufficient to provide for adequate drainage, and the size of each of the small pieces will be too large and will not provide the desired edge effect provided by the present invention. On the other hand, if a negative coefficient N is greater than 50%, the contact area becomes too small to provide sufficient driving stability, as well as the necessary driving performance on ice.

In the above description covers only the individual embodiments of the present invention, the composition described above may be combined with each other and/or they can be made various changes, provided that such combinations/modifications do not deviate from the essence of the tee of the present invention. For example, according to the present invention, the shape of the outer surface of the small checkers 3 is not limited to octagonal or round shape, also valid oval shape, other polygonal shape or an asymmetrical closed form. In addition, the longitudinal main groove 4 is not limited to form end-to-end segment passing linearly in the longitudinal direction of the treadmill. The longitudinal main groove 4 may be curved, for example, wavy. In addition, ribbed cross section 6 is not limited to form, continuously passing in the longitudinal direction of the treadmill, and may also have a zigzag or wavy shape. In addition, although from the point of view of efficiency it is desirable that the group of small checkers were held throughout the treadmill, a group of small checkers can also take place only on certain parts of it.

Examples

Were prepared by the tires of examples 1 to 3 according to the present invention, a standard tire-Sample 1 produced by the conventional methods, and bus-comparative Samples 1 to 3 and assess their driving performance on ice/snow, indicators for drainage and to prevent uneven wear, the results of the assessment are provided below.

The tire of example 1 is a radial tire for passenger cars. The bus is on a treadmill tread pattern shown in figure 1, and size 205/55R16. Throughout the treadmill such tires are a group of smaller pieces, consisting of many small pieces, formed by the grooves and located next to each other. Tire of example 1 in the group of small checkers has one longitudinal main groove containing end-to-end plot linearly passing in the longitudinal direction of the treadmill. Width W1longitudinal main grooves is the same as the width of the cross-cutting area of the groove is equal to 14 mm, the Depth of the longitudinal main groove is 8.3 mm Ribbed sections respectively located on both sides of the longitudinal main grooves, each ribbed cross section continuously runs in the longitudinal direction of the treadmill and forms a side wall of the longitudinal main groove. The width of the ribbed cross-country area, measured in the transverse direction of each ribbed Jogging area, a minimum of 7.6 mm and a maximum of 11.5 mm Other characteristics of the tire of example 1 are shown in table 1.

The tire of example 2 is a radial tire for passenger cars. The bus is on a treadmill tread pattern shown in figure 2, and the size 205/55R16. The tire of example 2 was the same as the tire of example 1, with the only difference that ribbed Jogging area has slit drainage grooves pohodami is linear in the transverse direction of the treadmill, the width of each is 0.5 mm, the depth of each is 4.5 mm Other characteristics of the tire of example 2 are shown in table 1.

The tire of example 3 is a radial tire for passenger cars. The bus is on a treadmill tread pattern, shown in figure 3, and the size 205/55R16. Tire of example 3, there are two longitudinal main grooves containing end-to-end sections, each end-to-end site runs linearly in the longitudinal direction of the treadmill. The distance between the equator of the tire and each of these longitudinal main grooves of different width such longitudinal main grooves is also different from each other. Tire installed on the vehicle, the longitudinal main groove located on the inner side of the vehicle (i.e. the longitudinal main grooves shown in the figure on the left), the distance X1from the equator of the tire to the centerline of the longitudinal main groove is 21.9 mm From the longitudinal main groove located on the outer side of the vehicle (i.e. the longitudinal main grooves shown in the figure to the right), the distance X2from the equator of the tire to the centerline of the longitudinal main groove is 48 mm Width W1the left longitudinal main grooves is the same as the width of the cross-cutting area of the groove and is 16.5 mm Width W2right main longitudinal to the skill sets are the same as the width of the cross-cutting area of the groove and is 11 mm on one side (outer side) of each of the longitudinal main groove has a ribbed cross section, each ribbed cross section is formed on the surface of the longitudinal main groove and continuously runs in the longitudinal direction of the main groove. The width of each ribbed Jogging area, measured in the transverse direction of each ribbed cross-country area is not less than 7.6 mm and not more than 11.5 mm Other characteristics of the tire of example 3 is shown in figure 1.

For comparison were prepared by the standard-bus Sample 1 and bus-a comparative Sample 1, standard-tire Sample 1 was radial tyre size 205/55R16, and the tread had a negative coefficient 31.9% on the entire surface of the treadmill, as shown in figure 4, the tire of comparative Sample 1 was radial tyre size 205/55R16, and the tread had a negative 32.6% on the entire surface of the treadmill, as shown in figure 5. The standard bus of the Sample 1 on the entire surface of the treadmill were many rectangular pieces, formed longitudinal grooves acting as the main grooves, passing in the longitudinal direction and lateral grooves intersecting at a right angle about the Aulnay grooves. The width of the longitudinal grooves was 3 mm, and the depth of the longitudinal grooves was 8.5 mm Width of the lateral grooves was 7.9 mm, and the depth of the lateral grooves was 8.5 mm in Addition, each piece had three straight slit drainage grooves. The tires of comparative Sample 1 on a treadmill were many rectangular pieces, formed by longitudinal grooves, acting as the main grooves, passing in the longitudinal direction and lateral grooves intersecting at right angles with the longitudinal grooves. The width of the longitudinal grooves was 1.2 mm, and the depth of the longitudinal grooves was 8.5 mm Width of the lateral grooves was 4.5 mm, and the depth of the lateral grooves was 8.5 mm in Addition, each piece had two straight slit drainage grooves. Other characteristics are shown in table 1.

For another comparison were prepared bus-comparative Sample 2 and bus-a comparative Sample 3, the tire of comparative Sample 2 was radial tyre size 205/55R16 and had a tread pattern shown in Fig.6, the tire of comparative Sample 3 was radial tyre size 205/55R16 and had a tread pattern shown in Fig.7. The bus-comparative Sample 2 in the group of small checkers was not a longitudinal main grooves or ribbed egoboo plot. The bus-comparative Sample 3 in the group of small checkers had longitudinal main groove, but there was ribbed cross-country area. Other characteristics are shown in table 2.

Assessment of driving performance

Each of the samples described above tire was installed on the rim size is 6.5J×16, inflated to 220 kPa (relative pressure) and installed on the vehicle. After that conducted the following tests to assess driving performance.

(1) Evaluation of braking performance on ice.

Evaluation of braking performance on ice was performed by measuring the braking distance after pressing the brake pedal to the floor at a speed of 20 km/h on icy roads. The obtained test results are shown in table 2. Table 2 shows the results of the test tires-samples 1 through 3, as well as tire-comparative samples 1 to 3 in coefficient ratio relative to a standard bus of the Sample 1, and the results of the tests, the standard-bus Sample 1 taken as 100. The higher the value of each outcome, the better the braking performance on ice.

(2) Evaluation of subjective running performance on snow.

Assessment of subjective running performance on snow was carried out by the driver-pilot when driving in different modes of riding on the proving ground, covered with the m snow was given a comprehensive subjective evaluation of braking performance, acceleration, motion in a straight line and movement in the rotation. The results are given in table 2. Table 2 shows the results of the test tires-samples 1 through 3, as well as tire-comparative samples 1 to 3 in coefficient ratio relative to a standard bus of the Sample 1, and the results of the tests, the standard-bus Sample 1 taken as 100. The higher the value of each outcome, the better the subjective running performance on snow.

(3) Evaluation of braking performance on snow.

Evaluation of braking performance on snow was carried out by measuring the braking distance after pressing the brake pedal to the floor at a speed of 40 km/h on the road surface from the compacted snow. The results are given in table 2. Table 2 shows the results of the test tires-samples 1 through 3, as well as tire-comparative samples 1 to 3 in coefficient ratio relative to a standard bus of the Sample 1, and the results of the tests, the standard-bus Sample 1 taken as 100. The higher the value of each outcome, the better the braking performance on snow.

(4) Test for drainage.

Evaluation indicators for drainage was carried out by measuring the speed limit before the emergence of the effect of aquaplaning when driving straight on a wet road is covered and with a layer of water of thickness 5 mm The results are given in table 2. Table 2 shows the results of the test tires-samples 1 through 3, as well as tire-comparative samples 1 to 3 in coefficient ratio relative to a standard bus of the Sample 1, and the results of the tests, the standard-bus Sample 1 taken as 100. The higher the value of each outcome, the better indicators for drainage.

(5) Assessment of driving stability on a dry road surface.

Assessment of driving stability on a dry road surface subjectively produced a driver's test in different modes drive on a dry road surface. The results are given in table 2. Table 2 shows the results of the test tires-samples 1 through 3, as well as tire-comparative samples 1 to 3 in coefficient ratio relative to a standard bus of the Sample 1, and the results of the tests, the standard-bus Sample 1 taken as 100. The higher the value of each outcome, the better driving stability on a dry road surface.

(6) Assessment to prevent uneven wear.

Assessment to prevent uneven wear was carried out by measuring the gradation at the adjacent checkers (the degree of wear from one to the other edge) after a distance of 5000 km on a dry road surface. The results are given in table 2. Table 2 shows the financial p the tats test tires-samples 1 to 3, and tires-comparative samples 1 to 3 in coefficient ratio relative to a standard bus of the Sample 1, and the results of the tests, the standard-bus Sample 1 taken as 100. The higher the value of each outcome, the better the performance for preventing uneven wear.

The results of the tests are shown in table 2, confirm that the tire of the present invention, in addition to drastically improve the running performance on ice/snow, also helps to improve the drainage. In addition, as confirmed by the results of comparisons with the tire of comparative Example 3, the present invention allows to prevent uneven wear, as well as to improve the above-mentioned indicators. In addition, as confirmed by the comparison of Sample 1 with Sample 3, by increasing the number of longitudinal main grooves can improve the drainage and running performance on snow.

Industrial applicability

The present invention allows to improve the drainage, preventing uneven wear, as well as by optimizing the tread to significantly improve the running performance on ice/snow.

Description reference positions

1 Cross section

2 Groove

3 Small piece

4 Longitudinal main ditches is and

5 Surface grooves

6 Ribbed cross section

7 Slit drainage groove

GBThe small group of checkers

PL Estimated step length of a small group of checkers in the longitudinal direction

W Width of a small group of checkers

Z the Computational domain.

1. Pneumatic tire with a small group of checkers, located on at least part of the running area, and includes many small pieces, each of which is formed by grooves, and located next to each other in the longitudinal direction in a row containing
at least one longitudinal main groove, passing through a group of small pieces in the longitudinal direction of the treadmill;
at least one ribbed area located adjacent to the longitudinal main groove, and forming a side surface of the longitudinal main groove, continuously passing in the longitudinal direction;
numerical density D small checkers is in the range from 0.003 to 0.04 (pieces/mm2) and represents the number of small checkers unit actual area of the contact spot of a small group of checkers and is calculated by the formula: D=a/{PL·W·(1-N/100)-S},
where PL (mm) represents a small step checkers 3 in group GB,
W (mm) represents the width of GB(equal to the width TW of the contact spot of the treadmill, because what about this variant implementation checkers 3 are located around the Jogging section 1),
while (PCs) denotes the number of pieces 3, located in the computational domain Z (hatched area in the drawing) of GBlimited by the length of the pitch PL and width W,
N (%) indicates a negative factor in the computational domain Z,
S (mm2) denotes the surface area of the ribbed cross-country area, located in the computational domain.

2. The tire according to claim 1, characterized in that ribbed Jogging area has slit drainage grooves made with the possibility of closing when touching ribbed cross-country area with the road surface.

3. The tire according to claim 2, characterized in that the width of the slit of the drainage grooves is in the range from 0.2 mm to 2.00 mm

4. Tire according to any one of claims 1 to 3, characterized in that the side wall is ribbed Jogging area adjacent to the longitudinal main groove, passes linearly in the longitudinal direction of the treadmill.



 

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FIELD: transport.

SUBSTANCE: invention relates to tread of tires to be used in winter. Block central side has two open grooves while closed grooves are made on both sides of tire open grooves in circumferential direction. Depth of open grooves makes 50-70% of the depth of first circumferential main groove while depth of closed groove makes 105-140% of open groove depth.

EFFECT: good performance on ice, rigidity of blocks.

7 cl, 2 dwg, 1 tbl

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SUBSTANCE: invention relates to tread of tires to be used in winter. Tread 10 has multiple blocks 16. Multiple splines 18 are made on wear face 10A of blocks 16. Ledges 22 are arranged in splines 18 on surface of first wall of two surfaces 1804 of spline opposite walls while recesses 24 are made on surface of second wall of said spline to engage with said ledges 22. Engagement of said ledges and recesses suppress collapse of the components of blocks 16 located between splines 18. Height H1 of ledges 22 located on surfaces 1804 of spline walls 18 on edges of blocks 16 exceeds height H2 on surfaces 1804 of other splines 18. Therefore, collapse of the components of blocks 16 located on block edges in lengthwise direction is eliminated.

EFFECT: better braking on ice.

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SUBSTANCE: invention relates to tread of tires to be used in winter. Pneumatic tire comprises splines 2 with ledges 2 on first of its two opposed walls and aligned therewith along contour of recess 3 on second wall of said spline. Besides, projection of wall spline with ledges 2 in open state features relationship between density of location of X ledges in area extending to half the depth of alpine H from open side of spline 1, and density of location of ledges Y in area extending to half the depth of alpine H from base of spline 1 is given by X>Y.

EFFECT: better braking on ice.

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EFFECT: better tire tread characteristics on wet road surface and on snow, higher wear resistance.

10 cl, 7 dwg, 2 tbl

FIELD: transport.

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Pneumatic tire // 2468931

FIELD: transport.

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Air tire // 2467885

FIELD: transport.

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FIELD: transport.

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EFFECT: better bite on damp or icy roads.

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FIELD: transport.

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FIELD: transport.

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EFFECT: improved performances on ice.

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FIELD: transport.

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FIELD: transport.

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EFFECT: higher safety and reliability in motion on rod and ice.

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FIELD: transport.

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EFFECT: higher safety and reliability in motion on rod and ice.

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Land rover tire // 2467882

FIELD: transport.

SUBSTANCE: invention relates to automotive super-low pressure tires for use on impassability and soils of low bearing capacity. Proposed tire rated at 0.005-0.070 MPa comprises tread, carcass made of rubberized cord, side strips with cord layers turned up to bead rings. It has lengthwise grooves separating tread cleats of its central part from central ribs. Note here that the ratio between tire profile height and width varies from 0.45 to 0.7.

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FIELD: transport.

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FIELD: transport.

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FIELD: transport.

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EFFECT: better bite.

28 cl, 7 dwg, 1 tbl

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