The Yokohama Rubber Co., Ltd.

Hirokatsu Maruyama

Takumi Morito

Kohtaroh Iwabuchi

Kazuhiro Shimura

Hiroshi Iizuka

Satoru Isobe

Hironori Kobayashi

Atao Kishi

Toshiro Oyama

In a pneumatic tire, 48%&#x2266;HB/HA&#x2266;52%, 98%&#x2266;HC/HA&#x2266;100%, 108%&#x2266;WB/WA&#x2266;115%, and 55%&#x2266;WC/WA&#x2266;75% are satisfied, where, when a line from a position A of rim height FH in tire width direction is X-axis and a line in tire radial direction via center crown CL is Y-axis, WA is distance of a half of tire base width, WB is distance from the Y-axis to a maximum width position P of a carcass layer, WC is distance from the Y-axis to an inflection point Q of the carcass layer, HA is distance from the X-axis to a peak R of the carcass layer on the center crown CL, HB is distance from the X-axis to the maximum width position P, and HC is distance from the X-axis to the inflection point Q.

Pneumatic tire

Disclosed is a pneumatic tire effectively controlling uneven wear occurring in the vicinity of a main groove even if a groove width of the main groove is widened due to change in tread radius during inflation. In the pneumatic tire, with regard to a zigzag-shaped main groove having the groove width widened during inflation among a plurality of main grooves provided on a tread surface, an inclination angle of a groove wall near the center with respect to the tread surface is made relatively large in a bent portion near the shoulder, an inclination angle of a groove wall near the shoulder with respect to the tread surface is made relatively large in a bent portion near the center, and regions where the inclination angles of the opposed groove walls are different from each other are uncontinuously arranged in the tire circumferential direction.

Pneumatic tire including zig-zag main grooves

A heavy-duty pneumatic radial tire is disclosed, which comprises a bead filler disposed on an outer periphery of an annular bead core; a carcass layer formed by arraying a plurality of steel cords in a tire radial direction, an end part thereof being turned up from the inside of the tire to the outside around the bead core; a steel reinforcing material wrapping around the bead core with the carcass layer interposed, and a bar-shaped transponder buried in an area separated from metallic components of a bead section in the bead filler so as to set a longitudinal direction thereof in a tire circumferential direction, the area being closer to the bead core than a turned-up end of the carcass layer in a turned-up side of the carcass layer, and closer to the bead core than an inner wrapping end of the steel reinforcing material in a main body side of the carcass layer.

Heavy-duty pneumatic radial tire with transponder buried in bead filler

A heavy duty pneumatic radial tire having sub grooves provided on a tread surface which has a center main groove and two outer main grooves. The sub grooves extend in the tire width direction and together with the main grooves, divisionally form two block rows composed of a plurality of blocks. The sub grooves are inclined in a direction opposite to the tire rotating direction from the center main groove toward the outer main grooves. The inclination angle of the sub grooves is gradually and continuously reduced from a first inclination angle measured at the center main groove to a second inclination angle measured at the outer main groove. The first inclination angle is set in the range from 70 to 90.degree. while the second inclination angle is set in the range of greater than 30.degree. and less than the first inclination angle. Further, notched grooves can be provided dividing the shoulder areas of the tread surface into a plurality of blocks. The notched grooves can be inclined in a direction opposite to the tire rotating direction.

Pneumatic radial tire for heavy duty

A pneumatic radial tire for heavy loads, formed by providing the shoulder side edge portions of at least the second inner ribs or block rows counted from the outermost parts of a tread portion with narrow ribs of a height equal to that of the ribs or block rows via narrow grooves, and chambering the edge portions of these narrow ribs or inclining the depthwise axes of these narrow grooves from a tread surface toward a tread center.

Growing community of inventors

Kanagawa, Japan

Hirokatsu Maruyama