公开(公告)号：MX9206505A

公开(公告)日：1994-06-30

申请号：MX9206505

申请日：1992-11-12

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO ,  YAMAGISHI JUNICHI ,  HACHIYA KAZUO ,  HASHIMOTO TAKATSUGU ,  AKUTAGAWA KEIZO ,  YAGAWA KAZUO

IPC: B60C1/00 ,  B60C11/00 ,  B60B21/00

Abstract: The invention provides a flame-retardant rubber tire comprising an outer rubber body portion consisting essentially of a tread rubber layer 2, a sidewall rubber layer 3 extending inwardly from each side edge of the tread rubber layer 2 toward the vicinity of a bead portion 8 in a radial direction and a rubber chafer layer arranged in the vicinity of the bead portion 8. A flame-retardant rubber composition having an oxygen index of not less than 19.8 but not more than 27.5 is disposed so as to amount to at least 20% by weight of the tread rubber layer 2. Such rubber tires are used in electric vehicles, automobiles, airplanes and the like and having excellent self-extinguishing property and flame-delaying property without damaging other rubber properties.

公开(公告)号：CA1314000C

公开(公告)日：1993-03-02

申请号：CA564744

申请日：1988-04-21

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO ,  MIYAMOTO KENJI ,  SHIMADA NORIHIRO

IPC: B60C11/04 ,  B60C11/12 ,  B60C11/06

Abstract: HEAVY DUTY PNEUMATIC RADIAL TIRES A heavy duty pneumatic radial tire comprises a tread divided into plural ribs by plural main grooves each extending zigzag circumferentially of the tire. The resistance to uneven wear is improved by regulating the pitch of the open sipe crossing the tread as well as the amplitude and pitch of the main groove in connection with the sipe pitch.

公开(公告)号：FR2617096A1

公开(公告)日：1988-12-30

申请号：FR8808241

申请日：1988-06-20

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO ,  MIYAMOTO KENJI

IPC: B60C9/08 ,  B60C11/00 ,  B60C11/01 ,  B60C3/00

Abstract: Radial tyre for heavy loads with high internal pressure, comprising a tread strip, the tyre being formed and vulcanised in a mould, the tread strip having an external contour inside the mould, this external contour consisting, in section, of a curve having a positive radius of curvature, a centre of curvature located on one side of the axis of the tyre at a central part of the tread strip extending between points "m" separated on either side of the centre of the tread strip by a distance equal to 0.64-0.85 times the half-width of the tread strip TW/2, and of a curve having a negative radius of curvature and a centre of curvature located on the opposite side with respect to the axis of the tyre, close to the shoulder parts of the tread strip which are located outside, in the axial direction, the points "m", the negative radius of curvature having an absolute value of 1 to 30 times the width of the tread strip TW. The value H3 for correcting the shoulder edge drop of the tread strip is within a range from 0.05 to 0.40 times H1, which is the value of the drop, in the radial direction, of the edge of the tread strip which would be formed in a mould having a single radius of curvature in section.

公开(公告)号：JP2000158909A

公开(公告)日：2000-06-13

申请号：JP33311098

申请日：1998-11-24

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO

IPC: B60C9/00 ,  B60C9/18 ,  B60C9/20 ,  B60C9/26 ,  B60C11/12

Abstract: PROBLEM TO BE SOLVED: To provide a pneumatic tire suitable for a main wheel tire of a new transportation vehicle by preventing deterioration in service life of a guide wheel road surface and preventing cracks at a bottom of a sipe. SOLUTION: A four-layer construction waved belt layer 24 consisting of multiple cords 22 meandering along a circumference of a tire prevents an increase of a diameter during charging an internal pressure and cracks at bottoms of sipes 34 on lands 32. Also, the waved belt layer 24 blocks influence of a slant belt layer 20 consisting of cords 18 slanting against the tire circumference direction to thereby greatly reduce a ply steerage. Accordingly, loads applied on guide wheels of a new transportation vehicle are reduced and deterioration in service life of a guide wheel road surface can be prevented.

公开(公告)号：JPH1158384A

公开(公告)日：1999-03-02

申请号：JP21753197

申请日：1997-08-12

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO

IPC: B60C11/00 ,  B29C33/02 ,  B29C35/02 ,  B29D30/52 ,  B29K21/00 ,  B29K105/04 ,  B29K105/24 ,  B29L30/00 ,  B32B25/00

Abstract: PROBLEM TO BE SOLVED: To provide a pneumatic tire manufacturing method for manufacturing a pneumatic tire for preventing the growth of cracks generated on a channel bottom section of a main channel of a cap tread formed of foamed rubber. SOLUTION: In an unvulcanized tread member 10 forming a tread after vulcanization molding, sections facing main channel forming protrusions 20 of a mold 16 of a cap tread rubber member 12 are formed thinner than sections facing areas between respective one main channel forming protrusion 20 of the mold 16 and another main channel forming protrusion 20. When an unvulcanized tread member 10 is vulcanization molded by the mold 16, the thickness of the cap tread rubber member 12 on the bottom of a main channel of a tire is 0.5 mm, and foamed rubber is not generated thereon. As the foamed rubber is not formed by the cap tread member 12 on the bottom of the main channel, even when ozone cracks are generated on the channel bottom, the growth of ozone cracks is prevented.

公开(公告)号：JPH0752609A

公开(公告)日：1995-02-28

申请号：JP21917393

申请日：1993-08-11

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO

IPC: B60C11/00 ,  B60C11/01

Abstract: PURPOSE:To avoid reduction of appearance and durability when mini-side rubber which covers a connection section of tread rubber with side rubber is applied on a pneumatic radial tire for high internal pressure heavy load. CONSTITUTION:A profile of outer ring in tire cross section has arcs 42, 44, 46, 48 having a center of curvature on the outer side of a tire in the vicinity of mini-side rubber 10, and a connection section of the mini-side rubber 10 which appears on an outer surface of the tire and side rubber 20 is positioned in a central part of the arcs 42, 44, 46, 48.

公开(公告)号：JPH06127208A

公开(公告)日：1994-05-10

申请号：JP27443292

申请日：1992-10-13

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO

IPC: B60C9/04 ,  B60C9/08

Abstract: PURPOSE:To distribute the distortion of ply ends to prevent ply end separation from occurring and also prevent air from entering the ply joint sections. CONSTITUTION:A pneumatic radial tire 10 is composed of a first ply 14 as an up-ply, a second ply 16, and a third ply 18 as a down-ply coated with a rubber layer 20. The first ply 14 and the second ply 16 are overlap-jointed, and the third ply 18 is butt-jointed. Because the radial outer end 14A of the first ply 14, the radial outer end 16A of the second ply 16, and the radial outer end 18A of the third ply 18 are arranged distributedly, distortion is not concentrated on one point to prevent ply end separation from occurring. Also, because the surface of the outmost third ply 18 as butt-joint is smooth, it can be prevented that air enters when a first belt 26 is stuck on it.

公开(公告)号：JPH02164603A

公开(公告)日：1990-06-25

申请号：JP31651588

申请日：1988-12-16

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO

IPC: B60C9/18 ,  B60C9/20 ,  B60C9/28

Abstract: PURPOSE:To advantageously delay the time of crack generation to a rubber situated in and around the side end part of a belt layer by setting the rubber thickness between adjacent belt layers to specified times the thickness of the lateral center part thereof on the side end part of the belt layer. CONSTITUTION:A tire applied to vehicle for subway and the like is provided with a carcass 1 consisting of one layer or more of plies, a belt 2 having a plurality of belt layers 4, 5 each code of which is extended in the direction crossing to the tire equator surface X-X, and a tread part 3 forming the tire thread. In this case, the rubber thickness between adjacent belt layers in which the extending direction of the code in each of belt layers 4, 5 is directed in mutually opposite directions to the tire equator surface X-X, in other words, the rubber thickness between respective belt layer 4, 5, is set to 2-5 times the thickness of the tire lateral directional center part C on the outer end part, in the tire width direction, of respective belt layers 4, 5 in the side end position E of the narrower belt layer 4, for example, when one belt layer 4 is narrower than the other.

公开(公告)号：JPH02158402A

公开(公告)日：1990-06-18

申请号：JP31020488

申请日：1988-12-09

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO

IPC: B60C9/18 ,  B60C11/04 ,  B60C11/12

Abstract: PURPOSE:To improve the extent of abrasive resistance as well as to abate a sipe tear by forming an innermost layer among three steel belt layers into a hollow structure, and setting width of the three layers and width of the hollow part to a specified relationship, while extending an outer end of a sipe in the same side as the extending direction of a cord at the outermost layer. CONSTITUTION:An innermost layer steel belt layer 6 is formed into a hollow structure removing a central part in the tire width direction. In addition, width W1 of an intermediate layer steel belt layer 5 is made larger than each width W2 of other steel belt layers 4, 6, setting it to 80 - 110% of tread width W. Each width W2 of these innermost and outermost steel belt layers 4, 6 is set to 80 - 98% to the width W1 of the intermediate layer steel belt layer 5. Then, hollow width W3 of the innermost layer steel belt layer 6 is set to 15 - 50% with the width W1 of the intermediate layer steel belt layer 5. On the other hand, an outer end in the tire width direction of each sipe 10 is extended at the same side in the extending direction of a cord in the outermost layer steel belt layer 4.

公开(公告)号：JPS641608A

公开(公告)日：1989-01-06

申请号：JP15539787

申请日：1987-06-24

Applicant: BRIDGESTONE CORP

Inventor： TANAKA MAKOTO ,  MIYAMOTO KENJI ,  SHIMADA NORIHIRO

IPC: B60C9/08 ,  B60C11/00 ,  B60C11/01

Abstract: PURPOSE:To improve resistance to partial wear, of the title tire for a bus and the like, by forming a shoulder portion outer contour, axially outside from a specific point on a tread, in a specific negative radius of curvature so as to form a shoulder falling to a specific correcting value. CONSTITUTION:The inner/outer contours of a mould on a tread center portion, away from a tread center CL to a point of 0.64-0.85 times the half width of a tread, is formed at a positive radius of curvature R1 having its center of curvature on the tire axis side, and the outer contour of a shoulder outside of this point is formed at a negative radius of curvature R2, 1-30 times a tread width. Furthermore, a tread shoulder portion falling correcting value H2 is set at 0.05-0.04 times the head H1 at a single tread crown radius of curvature. Hence the charge of operating internal pressure will cause the whole area of the outer contour to expand outwardly in the axial direction beyond the tread outer contour and its ground contacting shape in loading to be nearly rectangular. This constitution improve resistance to partial wear.