Abstract: The collapse of conductive terminal rubber strips is prevented while a conductive terminal portion is formed stably to have an exposure width of 5 mm or less. The conductive terminal portion is formed by continuously winding the terminal strips formed of a conductive rubber toward an outward radial direction from a tread conductive layer to a tread ground contacting surface. The terminal strip is sequentially wound while shifting a position at a pitch D of a distance in a tire axial direction while the terminal strip goes around such that the conductive terminal portion constitutes a trapezoidal cross section in which a width (Wa) of an upper base is smaller than a width (Ws) of the terminal strip and a width (Wb) of a lower base is larger than the width (Ws) of the terminal strip. The width (Wa) of the upper base is within a range of between 2 mm and 5 mm.

Abstract: The collapse of conductive terminal rubber strips is prevented while a conductive terminal portion is formed stably to have an exposure width of 5 mm or less. The conductive terminal portion is formed by continuously winding the terminal strips formed of a conductive rubber toward an outward radial direction from a tread conductive layer to a tread ground contacting surface. The terminal strip is sequentially wound while shifting a position at a pitch D of a distance in a tire axial direction while the terminal strip goes around such that the conductive terminal portion constitutes a trapezoidal cross section in which a width (Wa) of an upper base is smaller than a width (Ws) of the terminal strip and a width (Wb) of a lower base is larger than the width (Ws) of the terminal strip. The width (Wa) of the upper base is within a range of between 2 mm and 5 mm.

Abstract: A green tire includes a surface layer defining a green tire surface and made up of a plurality of windings of an unvulcanized rubber tape. A part of each of the windings is exposed on the green tire surface so that the exposed part has a width of from 50% to 80% of the width W1 of the rubber tape. Each of the windings has a substantially rhomboid cross section and has one end at an acute angle corner exposed on the green tire surface and the other end at the opposing acute angle corner. An angle theta of a diagonal line of the rhomboid drawn between the one end and the other end is not more than 30 degrees with respect to a tangential line to a profile line of the green tire surface.

Abstract: Tire uniformity is improved. A method comprising a strip winding step S3 of forming strip-wound bodies 21 for forming bead apexes by circumferentially spirally winding a rubber strip 20 with an overlap on a ply inner portion 6A1a of a cylindrical ply 6A1 wound on a former, which is located axially inward of bead core setting positions P, and/or on ply outer portions 6A1b of the cylindrical ply 6A1, which are located axially outward of the bead core setting positions P, an expanding step S4 of toroidally expanding the ply inner portion 6A1a of the cylindrical ply 6A1, and a joining step S5 of turning up the ply outer portions 6A1b of the cylindrical ply 6A1 around bead cores 5 to sandwich the strip-wound bodies 21 between the toroidal ply inner portion 6A1a and the ply outer portions 6A1b, thereby joining them together.

Abstract: A rubber member for tires is formed by spirally winding an unvulcanized rubber strip. The rubber strip has a first longitudinal end portion for serving as a starting side of winding of the rubber strip and a second longitudinal end portion for serving as an end side of the winding. The end surface of at least one of the first end portion and the second end portion is an inclined surface inclining to the longitudinal direction line of the rubber strip.

Abstract: A pneumatic tire wherein at least 75% by weight of tire-constituting components based on the tire overall weight are made of nonpetroleum-based materials and wherein, at least, base rubber 2G2 and cap rubber 2G1 of tread rubber 2G, sidewall rubbers 3G and a topping rubber of carcass 6 are formed of an insulating rubber material, wing rubbers 2G3 of tread rubber 2G are formed of an electrically conductive rubber material, and sidewall portions are provided with at least one electrically conducting path 20 formed from a ribbon-like conductive rubber strip 21 made of an electrically conductive rubber material and having a width Ws of 10 to 40 mm, in which the conductive rubber strip 21 extends linearly in a radially inward direction from an electrically conducting part 21A contacting the wing rubber 2G3 to reach clinch rubber 4G.

Abstract: A pneumatic tire comprises a tread rubber comprising layers each formed by overlap winding a rubber tape. The rubber tape in each layer has a conductive part in the longitudinal direction of the tape and the remaining less-conductive part, wherein the conductive part is wound at least once around the tire. In the radially outermost layer, the conductive part is exposed in the tread surface by a total axial width WU of at least 1.0 mm. In the radially innermost layer, the conductive part appears in the radially inner surface so as to be electronically connected to a conductive underlying structure by a total axial width WL of at least 1.0 mm. Between the radially adjacent layers, the conductive part in the radially outer layer is connected to the conductive part in the radially inner layer by a total axial width WM of at least 1.0 mm. Preferably, the rubber tape is made of mainly a silica rich compound.

Abstract: A method for manufacturing a pneumatic tire with tread grooves comprises: building a green tire, and vulcanizing the green tire in a mold, wherein the building of the green tire includes making a tread rubber by overlap-winding a raw rubber tape, and the mold is provided with protrusions for molding the tread grooves on the tread rubber. During vulcanizing the green tire in the mold, one of the protrusions is positioned radially outside an end of the raw rubber tape so that the end is relatively pressed radially inwards of the tire by the protrusion.

Abstract: A green tire includes a surface layer defining a green tire surface and made up of a plurality of windings of an unvulcanized rubber tape. A part of each of the windings is exposed on the green tire surface so that the exposed part has a width of from 50% to 80% of the width W1 of the rubber tape. Each of the windings has a substantially rhomboid cross section and has one end at an acute angle corner exposed on the green tire surface and the other end at the opposing acute angle corner. An angle theta of a diagonal line of the rhomboid drawn between the one end and the other end is not more than 30 degrees with respect to a tangential line to a profile line of the green tire surface.