Abstract: A pneumatic tire has a tread pattern which comprises at least three circumferential grooves with a groove width of 6 to 18 mm and a groove depth of 6.0 to 16.0 mm extending in a tire circumferential direction, wherein, on groove walls on both sides forming the at least three circumferential grooves, first inclined walls inclined by an inclination angle of 5 to 20 degrees with respect to the tire circumferential direction and second inclined walls inclined by an inclination angle of 0 to 45 degrees with respect to a tire width direction are provided so as to be successively connected in the tire circumferential direction so that positions of groove ends in the tire width direction vary in the tire circumferential direction.

Abstract: A pneumatic tire (10) has an inner shoulder (11), an outer shoulder (12) and a tread (13) therebetween. The tread includes a plurality of circumferential grooves 30, 32, 34, 36 38) dividing the tread into a plurality of ribs including inner and outer shoulder ribs (14, 14?), inner and outer intermediate ribs (18, 18?) between the shoulder ribs and a central rib (16) between the intermediate ribs. First sipes (20) are provided in the shoulder ribs and the central rib. Each first sipe has an interlocking shape. Second sipes (22) are provided in the intermediate ribs. Each second sipe has a shape different from that of the first sipes. Third sipes (24) are provided in the intermediate ribs. Each third sipe has a shape different from that of the first and second sipes.

Abstract: A pneumatic tire is provided for enhancing its driving stability and braking performance on particular road surfaces. The pneumatic tire is provided with five main grooves, first and second lateral grooves, and first and second blocks. The five main grooves include a single first main groove, two second main grooves, and two third main grooves. The single first main groove is disposed on a tire equator. The first main groove is made of a see-through groove extending in the tire circumferential direction. The two second main grooves are disposed on two sides of the first main groove in the tire width direction. The first and the second lateral grooves are extending in the tire width direction. The first and the second blocks are formed in a center area of the tread surface between the two third main grooves. A sub-groove is disposed in each first block.

Abstract: In a tire, a phase difference L1 of transverse grooves 2 is within 25% of the length L of blocks 3, the projected portions 11 are alternately on both sidewalls 10, L2 of the portion 11 is 20% to 45% of L, and in the cross-section of the width direction of the main groove 1, the edge 15 of the portion 11 at the groove bottom is more of a sidewall 10 side than a center line 19 of the groove 1, the outline of the portion 11 is at least on a virtual surface 17 that connects the edge 13 of the groove 1 at the tread surface and the edge 15. The tire also has one or a plurality of sub-projected portions 21, 22 projected from the surface 17.

Abstract: The present invention enhances noise performance and anti-uneven wear performance. A pneumatic tire 1 includes a belt layer 7 including at least one belt ply in which belt cords 15 are arranged at an angle of 10 to 40° with respect to a tire equator C. A tread pattern formed on a surface of the tread portion 2 includes a pitch line 22 in which at least two kinds of pattern-constituting units 21 having different pitches in a circumferential direction of the tire are arranged in the circumferential direction of the tire. The belt cords 15 are arranged relatively densely on an inner side of the pattern-constituting unit 21 having a small pitch, and relatively thinly on an inner side of the pattern-constituting unit 21 having a large pitch.

Abstract: A tire is provided having a pitch sequence designed from this method. The pitch ratios are unevenly spaced. An exemplary tire has five pitch ratios of 1.00, 1.10, 1.25, 1.4, and 1.50.

Abstract: A pneumatic tire having a rotation direction specified in one direction. The tread surface has a main groove extending on the equatorial plane of the tire, right and left first inclination grooves extending in an inclined manner from the main groove toward the reverse rotation direction of the tire, and right and left second inclination grooves disposed on the opposite sides of the main groove. The right and left second inclination grooves are disposed at symmetrical positions with respect to the equatorial plane of the tire. Blocks are formed on the opposite sides of the main groove by the main groove, right and left first inclination grooves and right and left second inclination grooves.

Abstract: An in tire sound absorber for a pneumatic wheel assembly including a wheel rim and a tire fitted to the wheel rim. The sound absorber comprises a first fibrous layer and a second fibrous layer with a higher air flow resistance than the first layer. The sound absorber is configured to fit around the wheel rim with the first layer in contact with a surface of the wheel rim and extending substantially between the second layer and the wheel rim.

Abstract: Provided are: a noise reduction device with an improved adhesion of a noise absorbing member formed of a porous material and with a reduced processing time; a method of manufacturing the noise reduction device; and a pneumatic tire including the noise reduction device. The noise reduction device of the present invention includes: a noise absorbing member formed of a porous material; a band member for attaching the noise absorbing member to the inner surface of a tire; and locking members formed of a thermoplastic resin. The band member is formed of a thermoplastic resin. The noise absorbing member is disposed between the band member and the locking members. The locking members are bonded to the band member through the noise absorbing member by thermal fusion.

Abstract: Provided is a pneumatic tire in which improvement is achieved in a wet performance and reduction in vehicle exterior noise while ensuring a dry performance.

Abstract: A vehicle tire includes a tread provided with a tread pattern, which is made up of circumferentially arranged design units having a plurality of pitch lengths Pi (i=l to j) including a minimum pitch length Pl and a maximum pitch length Pj. Each of the design units has at least one groove with side walls each having an inclination angle ?i in a cross section parallel to the tire equator, and the inclination angle ?1 in the design unit having the minimum pitch length P1 is less than the inclination angle ?j in the design unit having the maximum pitch length Pj, whereby the rigidity difference between the design units having different pitch lengths is decreased. Preferably, the angle ?i in a design unit having a pitch length Pi is not more than the angle ?i+1 in a design unit having the next longer pitch length Pi+1.

Abstract: A pneumatic tire comprises a tread portion provided with annular regions each provided with axial grooves each extending from one of the axial edges of the annular region, wherein each axial groove is defined as having a groove width of from 2.0 to 6.0 mm and an axial length of not less than 40% of the axial width of the annular region. The annular regions are different from each other with respect to the number Nj of the axial grooves therein, and the greatest common divisor of the different numbers Nj of the grooved annular regions is in a range of from 10 to 40.

Abstract: A pneumatic tire is cured and molded by a sectional type tire mold including an annular side mold section having a tread forming surface for forming a tread surface, the side mold section comprising a plurality of sectors into which the side mold section is divided along a circumferential direction of the side mold section. A tread surface, which has first regions formed by sector divisional position vicinity regions of the side mold section and second regions formed by sector divisional position distant regions of the side mold section, has lands defined by at least one circumferential groove which extends in a circumferential direction of the tire. Sipes which extend from the at least one circumferential groove into at least one of the lands with their extension ends located within the at least one land are disposed at predetermined intervals along the tire circumferential direction. The sipes comprise first sipes in the first regions and second sipes in the second regions.

Abstract: A tire for a wheel of a vehicle includes a carcass, a belt structure, and a tread. The tread pattern includes at least two circumferential grooves and at least three circumferential ribs. The grooves include a zigzag configuration and a shape repeated according to a circumferential pitch. Within a single pitch, each groove includes at least two directions different from a circumferential direction of the tire, generating at least two ground-gripping fronts in each of two rotation directions of the tire, and at least one blind transverse cut extending from opposite sides of the groove, generating a third ground-gripping front. Ends of the blind transverse cuts are positioned on planes parallel to each other and to an equatorial plane of the tire. The first plane and the second plane delimit a continuous portion of at least one of the circumferential ribs. The continuous portion includes a constant axial width.

Abstract: A tread surface 2 is divided by inner and outer longitudinal grooves 3a and 3b located on opposite sides of the tire equator into a central land portion 4i, intermediate land portions 4m and shoulder land portions 4o. The intermediate land portion 4i includes an inclined grooves 9 having an angle ? with respect to the circumferential direction of the tire, and the angle is increased from an inner end (mi) away from the inner longitudinal grooves 3a by a small distance La to an outer end (mo) where the intermediate land portion intersects with the outer longitudinal grooves 3b. An angle ?i in the inner end (mi) is 0 to 25°, and an angle ?o in the outer end (mo) is 60 to 80°. A pitch P1 of the inclined grooves 9 in the circumferential direction is greater than a pitch P2 of lug grooves 5 provided in the shoulder land portion 4o in the circumferential direction.

Abstract: A tire tread, comprising a tread pattern formed of groups of motifs arranged, in the transverse direction, in a number M of distributions at least equal to two and of average width Li, Lj, the total of the widths Li, Lj being at least equal to 80% of the width L of the tread, each distribution of groups of motifs being formed by a succession of a plurality of groups, at least two of said groups of motifs of the distribution in question having different longitudinal lengths, the ratio Ri between the longitudinal length of the smallest group of motifs and the largest group of motifs being strictly less than one, this tread being characterized in that for at least two distributions comprising respectively Ni and Nj motifs, with Ni<Nj, the following relationships are satisfied: 0.20?Tij?0.50, 0.60?Rpg?0.

Abstract: A pneumatic tire has a tread extending along the circumferential length of the tire. The tread is divided into at least two different regions across the width of the tread, and has a plurality of tread elements. Each tread element has a pitch length as measured along the circumferential length of the tire. In each of the tread regions, different pitching methods are employed. Preferably, the different pitch methods are selected and the pitch lengths in each region are arranged so that the noise frequency contribution generated in each tread regions cancels or eliminates the noise frequency contribution generated in the other tread regions.

Abstract: The manufactured pieces are the ones both end surfaces thereof in the tire circumferential direction are cut from the pieces before cutting 1 and the pieces before cutting 1 have the cutting regions whose cross-sectional shapes in the tire width direction are the same at both ends of its circumferential direction. And in the cutting process of cutting the pieces for modifying the lengths in the circumferential direction from each of the pieces before cutting 1, in order that the length in the tire circumferential direction of each piece after cutting and that both of the end surfaces in the circumferential direction of the piece after cutting are included in the cutting regions, the cutting lines of each piece are set at different not less than two positions (a, a? and b, b?) in the tire circumferential direction and the pieces are cut by either one of the set cutting lines.

Abstract: The invention provides a method for balancing tire performance with both increased and decreased numbers of lugs on the ribs while also having desirable tire noise performance. This method allows the tire designer to take advantage of the benefits of both high and low pitch count patterns while minimizing undesirable tire noise. The method involves the design of the fundamental pitch of the tire tread pattern and the design of the tread pattern for the tire. The invention also provides tires incorporating the fundamental pitch and tread patterns.

Abstract: When variable pitches are classified into a plurality of groups (S, M, and L) depending on lengths thereof in the tire circumferential direction, all the differences of the average pitch lengths of one of the groups and the average pitch lengths of the other groups are 3 to 30 mm and in at least one group of the groups, any one of the pitch of the group differs from the average pitch length (PM) and among the differences of the average pitch lengths, when the minimum difference is defined to be Xmin, the pitch lengths of all the pitches of each group (M group) are modified to have the values of ±10% of the minimum difference is defined to be Xmin based on the average pitch length of the group.

Abstract: A pneumatic tire 10, in which at least one rib groove 12 extended in a tire circumferential direction is formed on a tread surface portion T of a tread portion 11, and portions 13 discontinuous in terms of rigidity are formed in a circumferential direction of rib lines B formed by the rib groove 12, the discontinuous portions 13 causing variations of tire axle force. Rigidity changing portions 20 which cancel the variations of the tire axle force are provided in the rib groove 12, the variations being caused by the discontinuous portions 13. Thus, vibrational force to an axle is lowered, and pattern noise caused thereby is reduced effectively.

Abstract: A winter tire containing a central vertical groove which extends along a tire equator C, and rib portions 6a and 6b having sipes S are formed on the opposite sides of the central vertical groove. At a groove edge line 3E of the central vertical groove, reference pitches P each comprises a main portion extending from an outermost origin N1 in a tire axial direction to a terminal end N2 closest to the tire equator, and an auxiliary portion 3b having a length in the tire circumferential direction smaller than that of the main portion 3a and passes through said origin N1 from said terminal end N2, and the reference pitches P are repeated in the tire circumferential direction into a zigzag configuration. A tire circumferential direction length of the main portion is 60% or more of a tire circumferential direction length of the reference pitch P.

Abstract: A pneumatic tire includes a tread portion provided with shoulder blocks in a row along each tread edge. The shoulder blocks are provided in a row divided by a circumferential groove and first shoulder grooves and second shoulder grooves. The first and second shoulder grooves alternate in the tire circumferential direction and each extend from the circumferential groove to the tread edge. A circumferential width (WLo) of the first shoulder groove at the tread edge is larger than a circumferential width (WSo) of the second shoulder groove at the tread edge. The ratio (WLo/WSo) of the circumferential width (WLo) to the circumferential width (WSo) is larger than a ratio (WLi/WSi) of a circumferential width (WLi) of the first shoulder groove to a circumferential width (SWi) of the second shoulder groove, each measured at the circumferential groove.

Abstract: A method of comparing tire noise pitch sequences based on the tire noise generated by tire tread lug stiffness variations provides a secondary examination technique used to evaluate tire noise pitch sequences that have been selected by traditional evaluation techniques. The method includes the steps of defining the tire noise pitch sequence and the pitch lengths, calculating the differential between the arc length from an arbitrary fixed reference point to the end of each pitch length in the pitch sequence and the arc length of the mean pitch length of the number of pitches from that arbitrary reference point, and analyzing the differential to identify desirable and undesirable tire noise characteristics.

Abstract: A pneumatic radial tire for all-season passenger car comprises a tread with a tread block pattern defined by plural slant grooves and at least one circumferential center groove and consisting of a central zone having a width corresponding to 30-60% of a tread width and a pair of side zones located on both sides of the central zone, wherein the slant grooves comprise steeply slant grooves and gently slant grooves each having a given shape, and the number of the gently slant grooves is made two times or more than the number of the steeply slant grooves, and the block is provided with at least one sipe, and each of the blocks defined by the circumferential center groove and the steeply slant grooves is chamfered from a tapered top end over a given range toward a longitudinal direction of the block.

Abstract: A method of controlling uniformity during tire manufacture includes the steps of selecting a target attribute and assigning a target value thereto, measuring the target attribute in a subject tire at a first rotational speed approximating highway speed and measuring in the subject tire indicator attributes a second rotational speed lower than the first rotational speed. The indicator attributes are condensed via a multivariate process to determine which attributes are the most strongly related to the target attribute. Next, a plurality of predictors for the target attribute is determined, each predictor having components including at least one indicator attribute. From the plurality of predictors, at least one best predictor is selected.

Abstract: A pneumatic tire for use in rough terrain which is provided in the tread with central blocks, shoulder blocks and intermediate blocks; in the tread developed in a plane, the central blocks are arranged circumferentially of the tire at substantially constant pitch lengths P1, the intermediate blocks in each intermediate region are arranged circumferentially of the tire at substantially constant pitch lengths P2, the shoulder blocks in each shoulder region are arranged circumferentially of the tire at substantially constant pitch lengths P3; in a certain number (K) of circumferential positions, the central blocks are aligned with the intermediate blocks in the tire axial direction, the number (K) is in a range of from 6 to 32; these circumferential positions are provided circumferentially of the tire at regular intervals equal to the pitch length P1 multiplied by an integral number (n), the number (n) is in a range of from 3 to 8; and the pitch length P2 and pitch length P3 are equal to the pitch length P1 mult

Abstract: A method of arranging cyclic patterns in a tire tread is disclosed, wherein design cycles in each cyclic pattern are repeated in a pitch sequence; with respect to each of the design cycles, an averaged pitch of the pitch lengths of a predetermined number of subsequent design cycles is obtained; combinations of the sequences of the averaged pitches are defined by changing phase between the sequences; with respect to the averaged pitches of the combined sequences, crossover averages are obtained; from the crossover averages in each combination, a difference between a maximum and a minimum is obtained; from the differences of the combinations, a combination having a smaller difference is found; the cyclic patterns are arranged in accordance with the phase shift of the combination having the smaller difference.

Abstract: A method for determining preselected performance characteristics of a tire tread includes the steps of dividing the tread into a 3-D grid of cells; dividing a tread contact area into longitudinal and transversal strips; associating a longitudinal or transversal stiffness value with each strip using a linear relationship; assigning a preselected deformation state to each longitudinal and transversal strip; determining at least one single force, associated with each strip and acting in the longitudinal or transversal direction by means of the stiffness value and the deformation state; determining at least one total force associated with each contact area by summing all single forces, the total force representing at least one of the performance characteristics; determining a pattern of the total forces of all the contact areas; and analyzing the pattern of total forces to evaluate whether they assume values that optimize at least one preselected performance characteristic of the tread.

Abstract: A pneumatic tire for use on iced and snowed road surfaces has a tread surface. The tread surface has a plurality of main grooves extending in a circumferential direction of the tire and a plurality of lateral grooves extending in a width direction of the tire. Blocks are defined by the main grooves and the lateral grooves. The blocks have a ground contact face which has a plurality of pairs of sipes comprising a left sipe and a right sipe extending in the tire width direction. The plurality of pairs of sipes are placed in a predetermined interval in the tire circumferential direction. Each of the left and right sipes of each pair extends from a width-directional center portion of the ground contact face of the block toward each way of the tire width direction so as to open its outer end to each side face of the block.

Abstract: An all-terrain vehicle tire (10) operated at 4 psi (0.3 bar) or less inflation pressure has a plurality of lugs (44) arranged in a pitched pattern for noise reduction. The ratio of small (S), medium (M) and large (L) pitches are preferably arranged with a maximum pitch variation between circumferentially adjacent pitches of 1.1 to 1.

Abstract: A pneumatic tire has a tread portion curved so that the maximum section width of the tire lies between tread edges. The tread portion is provided with central blocks arranged circumferentially of the tire at pitches P1, axially outer blocks arranged circumferentially of the tire at pitches P3, and middle blocks arranged circumferentially of the tire at pitches P2 between the central blocks and axially outer blocks: the pitches P1 have a longer length than the pitches P2 and the central blocks, and the middle blocks are substantially aligned every two or more (number n) pitches P1; two or more circumferential positions at which the central blocks and the middle blocks are substantially aligned are provided around the tire; circumferential positions of the axially outer blocks are between the middle blocks.

Abstract: Tread profile of a snow tire for a vehicle in which at least two vehicle wheels are rotatably mountable outside of a longitudinal vehicle axis. The tread profile includes a plurality of profile block rows aligned in a circumferential direction and distributed in an axial direction from a first tire shoulder adapted to be positioned toward an outside of the vehicle in an operational state of the tire on the vehicle to a second tire shoulder adapted to be positioned toward an inside of the vehicle in an operational state of the tire on the vehicle.

Abstract: A vehicle tire comprises a central tread portion divided into central blocks B0 by central oblique grooves (g); a lateral tread portion divided into four kinds of blocks B1, B2, B3 and B4 by first and second oblique grooves (ga and gb) extending from a circumferential groove (G) to a tread edge, and cross oblique grooves (gc) extending between the first oblique grooves (ga1) while crossing the second oblique groove (gb); the central oblique grooves (g) and the cross oblique grooves (gc) inclined reversely to the first and second oblique grooves (ga and gb); the number of each of the first to fourth lateral blocks B1 to B4 in each of the lateral land portions being equal to the number of the central blocks B0; and each of the first oblique grooves (ga) and two of the cross oblique grooves (gc) meeting with at axially different positions (P1 and P2).

Abstract: A tread 20 has an equatorial centerplane and a plurality of tread elements 40, 42, 44 oriented into a first shoulder row 22, a second shoulder row 24 and a central array 30. The central array 30 forms a repeating pattern of tread elements 40 wherein each array 30 has at least five tread elements 40 distinct in size, shape or orientation relative to adjacent tread elements 40 within the array. The array 30 extends circumferentially adjacent the first or second shoulder row 22, 24 and has a centerline L inclined less than 45° relative to the equatorial centerplane. Each array 30 forms a large distinctive mosaic pattern repeating around the tread circumference, the array 30 having at least two rows of tread elements 40 oriented with at least one tread element 40 being on each side of the centerline L at the equatorial centerplane of the tread 20.

Abstract: A pneumatic radial tire, wherein five main grooves extending in the circumferential direction of a tire are provided on a tread to divide into and form land portions of six rows, each land portion is divided into block rows constituted by a plurality of blocks by means of a plurality of subgrooves extending in the direction of width of the tire, and an area ratio of the blocks is set at a relationship of 1:0.9 to 1.1:1.8 to 2.2 from the block row of the shoulder side to the block row of the center side, in a region between ends of a belt layer having a maximum width embedded in said tread.

Abstract: A pneumatic tire for use in rough terrain which is provided in the tread with central blocks, shoulder blocks and intermediate blocks; in the tread developed in a plane, the central blocks are arranged circumferentially of the tire at substantially constant pitch lengths P1, the intermediate blocks in each intermediate region are arranged circumferentially of the tire at substantially constant pitch lengths P2, the shoulder blocks in each shoulder region are arranged circumferentially of the tire at substantially constant pitch lengths P3; in a certain number (K) of circumferential positions, the central blocks are aligned with the intermediate blocks in the tire axial direction, the number (K) is in a range of from 6 to 32; these circumferential positions are provided circumferentially of the tire at regular intervals equal to the pitch length P1 multiplied by an integral number (n), the number (n) is in a range of from 3 to 8; and the pitch length P2 and pitch length P3 are equal to the pitch length P1 mult

Abstract: A method of designing a tread unit that may be repeated in succession about the circumference of a tire to produce an acoustically acceptable tread pattern. The impact of an initial design of a tread unit on a road surface is simulated so that a determination of the number of pulses contained in the impact may be made. An analysis is then performed, based on the number of pulses, as to whether the tread unit design satisfies a predetermined acoustic criteria. If the tread unit design satisfies the acoustic criteria, it may be incorporated into the tire tread pattern. Otherwise, the method may be repeated with a modified tread unit design until the predetermined acoustic criteria is satisfied.

Abstract: A tread (1) for a tire with a preferred rolling direction, the tread having grooves (2) of substantially circumferential orientation which delimit ribs (30, 31, 32, 33, 35), at least one of which is provided close to each of its traverse edges with a plurality of incisions of width smaller than 1.5 mm. The incisions open onto the contact surface of the tread, are essentially parallel to one another, and having a mean inclination &agr; different from zero relative to the direction perpendicular to the rolling surface (S) of the tread.

Abstract: An apparatus and method that determines a maximum road friction coefficient for each wheel regardless of whether the tire is in a predetermined drive slip state, and whether the wheel is a driving wheel. The braking force of each wheel is calculated, and the longitudinal force of the tire of each wheel is calculated. Then, the driving force of the vehicle is calculated, and the lateral force of the tire of each wheel is calculated. Next, the reaction force of the road to each wheel is calculated, and the vertical load of each wheel is calculated. Finally, the ratio of variation in reaction force of the road to variation in composite slip ratio is calculated for each wheel. The sum of the ratio of the reaction force of the road to the vertical load, and the product of a predetermined coefficient and the ratio of variation in reaction force of the road to variation in composite slip ratios is calculated for each wheel as the maximum road friction coefficient.

Abstract: The present invention provides a pneumatic tire having a tread portion comprising a plurality of axially spaced apart essentially longitudinal grooves separating essentially longitudinal ribs. On at least one of said ribs, transverse grooves or cuts repeat in the circumferential direction to form first and second land portions wherein the first land portions comprise blocks having a circumferential length greater than that of the second land portions. Said second land portion acts as a sacrificial bridge which provides traction improvement and minimizes undesirable surface anomalies during the service life of the tire.

Abstract: A method and a device for reducing the internal noise of a vehicle produced during the rolling of the tire are described The device comprises a plurality of elements made from open-cell expanded materials, for example expanded polyethylene, or from fibers of the mineral or textile type. These elements are introduced into the tire during its mounting on the corresponding rim and are placed in the absence of restraints in the annular cavity delimited between the tire and the rim. As a result of the rolling of the wheel, the various elements, under the action of the centrifugal force, are moved and pushed in a random way towards the inner surface of the tire, producing a ragged surface whose presence, in combination with the open cells of said elements, modifies and damps the acoustic waves generated inside the tire during the rolling of the tire.

Abstract: A high-performance tire (1, 51) for a motor vehicle is provided with a tread (2, 52) comprising two deep circumferential grooves (3, 6, 53, 56) which separate a central region (7, 57) from two lateral shoulder regions (8, 9, 58, 59) provided with shoulder blocks (20, 120, 64, 164); in the tread (2, 52) the sum of the widths of the shoulder regions (8, 9, 58, 59) is equal to or less than 60% of its overall width L, the width of each shoulder region (8, 9, 58, 59) is not less than 20% of the overall width L, in that each of said circumferential grooves (3, 6, 53, 56) is adjacent, on the side further from said central region (7, 57), to a continuous track (22, 122, 66, 166) from which are branched transverse grooves (21, 121, 65, 165) which delimit the shoulder blocks (20, 120, 64, 164).

Abstract: A tire noise damper to be disposed in an annular tire hollow formed between a wheel rim and a pneumatic tire mounted thereon, the damper made of a flexible material and comprising a base to be secured to the wheel rim and at least one flap extending from the base to be risen radially outwards from the wheel rim by centrifugal force during running to block the annular tire hollow. For example, the damper comprises at least one annular elastic band to be put around the wheel rim, the annular band provided with at least one U-cut for forming a flap, and the base is formed by the remaining annular portion of the band. In another example, the damper is made of a strip of the fixable material having a certain length, the base is formed by one end portion of the strip, and the flap is formed by the remaining portion of the strip.

Abstract: A method of determining a tread pattern for a pneumatic tire, the method including the steps of defining a first unit as including at least one pitch which is not less than a standard long pitch (PLa) and at least one pitch which is not more than a standard short pitch (PSa); defining a second unit as including at least one pitch within one of a first range of not less than the standard long pitch (PLa) and a second range of not more than the standard short pitch (PSa) but not including a pitch within the other range; defining a third unit as all the pitches therein are more than the standard short pitch (PSa) and less than the standard long pitch (PLa); selecting a number of the first units, second units and third units from a total number of units (U); and determining a tread pattern composed of a series of units based on the selected first units, second units and third units.

Abstract: A tire noise reducing system comprises a wheel rim, a pneumatic tire to be mounted on the wheel rim and a noise damper to be disposed in an annular tire cavity enclosed by the wheel rim and the pneumatic tire mounted thereon, wherein the noise damper is made of a multi-cellular material whose volume S2 is in a range of not less than 0.4% of the volume S1 of said annular tire cavity. Preferably, the specific gravity of the damper is set in a range of from 0.005 to 0.06.

Abstract: A pneumatic tire for passenger car has a direction tread pattern defined by a plurality of circumferential grooves and a plurality of directional slant grooves arranged at given intervals in the circumferential direction, wherein a circumferential center rib is formed in the central zone of the tread by a pair of circumferential center grooves, and a pair of circumferential middle ribs are formed by the pair of circumferential center grooves and a pair of circumferential side grooves, and a pair of circumferential side ribs are formed by the pair of circumferential side grooves and a pair of tread ends, and the directional slant grooves are directional slant center grooves formed in the circumferential middle rib and directional slant side grooves formed in the pair of circumferential side ribs, provided that each of the directional slant center grooves is opened to either of the circumferential center groove and the circumferential side groove and terminated in the circumferential middle rib and each of the

Abstract: A tire tread having design cycles or pitches in which the circumferential lengths of repeated pitches are randomly modulated in certain selected sequences to reduce the amount of noise generated by the tire tread when the tire rolls on a road surface. The pitch sequences include three different circumferential pitch lengths including a group having a largest number of medium length (M) pitches, a smallest number of shortest length pitches (S) and a medium number of longest length (L) pitches. In one embodiment, the ratio of the three different pitches are 0.8 for the smallest length pitch (S), 1 for the medium length pitch (M) and 1.2 for the longest length pitch (L). 100 pitch sequences are proposed with the sequence L M S M S L M L M L M L M L M M L M L M L M L M L M being the preferred sequence which provides the most noise reduction. Ninety nine other pitches are also within a range to provide an acceptable level of noise reduction in a tire tread.

Abstract: A tire noise damper to be disposed in an annular tire cavity formed between a wheel rim and a pneumatic tire mounted thereon. The damper comprises an annular band-like body which is made of an elastomeric material and provided with at least one generally U-shaped cut oriented in a circumferential direction. The cutout formed by the at least one U-shaped cut forms a flap risen by a centrifugal force during running, and the remainder forms a base band to be put around a bottom of the wheel rim in an elongated condition. In order to reduce resonance of the air in the tire cavity in not only the fundamental mode but also the higher harmonic modes, the flap may have a relatively long length such that, when risen, a radially outer end portion thereof comes into contact with the radially inside of a tread portion of the tire. Further, the flap may be made of nonwoven fabric at least partially.

Abstract: A vehicle tire has an unidirectional tread pattern, and the tread portion is provided with two circumferential grooves to divide the tread portion into two outer parts and a central part there between, the central part being substantially continuous in the tire circumferential direction and formed symmetrically about the tire equator. The outer parts are provided with mirror-image patterns, each formed by circumferentially repeating pattern units having an average circumferential length, and the mirror-image patterns are circumferentially shifted from each other by a distance S of from 0.15 to 0.25 times the above-mentioned average circumferential length.