Abstract: Disclosed is a pneumatic tire in which formation of a belt layer is realized by using an integer number of strip pieces and without causing any overlap between the strip pieces, and a method of manufacturing the same. The method is a method of manufacturing a pneumatic tire provided with a belt layer composed of a plurality of strip pieces each of which is formed by pulling together and rubberizing a plurality of steel cords. In the method, when a width of the respective strip pieces, an applicable number of the strip pieces, a cord angle of the belt layer with respect to a circumferential direction of the tire, and a circumferential length of the belt layer are respectively denoted by A, N, ?, and L, an integer satisfying (N+1)×A/sin ?>L>N×A/sin ? is selected as the applicable number N, and the belt layer is formed by aligning the N strip pieces on a molding drum in the circumferential direction of the tire with equal spaces disposed between adjacent ones thereof.

Abstract: In a tire designing method, at least one of a tire profile shape, a shape of a tire component member and physical property data of the tire component member is tentatively selected as a parameter to prepare an initial tire model (30) representing the pneumatic tire by using a finite number of elements, and at least one of a stress acting on the initial tire model by the inner pressure filling processing and the physical property data used for the initial tire model is modified corresponding to a predetermined measure of elapsed time, to thereby deform the initial tire model and a tire profile shape after a change with time is predicted by using the deformed initial tire model.

Abstract: Disclosed is a method of designing rubber composite executed as follows. A shape of the rubber composite, a shape of the each part (i) constituting the rubber composite and physical properties of a rubber material used for each part (i) are tentatively selected respectively. Thereafter, the rubber composite is divided into many finite elements, and strain in each element is calculated by the finite element method to obtain maximum principal strain (?i)max of the elements in each part (i). Then, the tentative selections of the shape of the rubber composite, the shape of each part (i) and the physical properties of the rubber material, and the calculations by the finite element method are repeated until an allowance ratio Sia calculated as a ratio of strain (?i)b at break to the maximum strain (?i)max becomes equal to a specified reference allowance ratio S0 or higher in all of the parts (i).

Abstract: A method for tire parameter derivation, tire cornering characteristic calculation and tire design is used with a tire dynamic model constituted by using a plurality of tire dynamic element parameters including stiffness and friction coefficient and parameter defining a distribution of contact pressure of the tire. The parameters and tire cornering characteristic are derived by using the combined sum of squared residuals being obtained by weighted addition of a first sum of squared residuals of lateral force and a second sum of squared residuals of self-aligning torque. The tire dynamic model is a model for calculating a lateral force and for calculating a self-aligning torque separately as a lateral force-based torque component generated by the lateral force applied on a contact patch of the tire and a longitudinal force-based torque component generated by a longitudinal force applied on the contact patch of the tire.

Abstract: A golf ball whose core is covered with a cover, wherein the core is constituted of a rubber composition containing polybutadiene rubber and the cover is constituted of a resin composition composed of ionomer resin and diene rubber. A golf ball cover material composition composed of ionomer resin, diene rubber and non-staining antioxidant. A method of manufacturing a golf ball cover material composition constituted by mixing/kneading ionomer resin and diene rubber.

Abstract: A golf ball whose core is covered with a cover, wherein the core is constituted of a rubber composition containing polybutadiene rubber and the cover is constituted of a resin composition composed of ionomer resin and diene rubber. A golf ball cover material composition composed of ionomer resin, diene rubber and non-staining antioxidant. A method of manufacturing a golf ball cover material composition constituted by mixing/kneading ionomer resin and diene rubber.

Abstract: A joint boot for protecting a joint part of a power transmission system, in particular a joint boot for improving the durability by reducing a local stress concentration. The joint boot comprises a cylindrical bellows part, and annular mounting parts formed at both ends of the bellows part, a ridge portion and a bottom portion of said bellows part being formed in a continuous spiral shape.

Abstract: Disclosed is a method of designing rubber composite executed as follows. A shape of the rubber composite, a shape of the each part (i) constituting the rubber composite and physical properties of a rubber material used for each part (i) are tentatively selected respectively. Thereafter, the rubber composite is divided into many finite elements, and strain in each element is calculated by the finite element method to obtain maximum principal strain (&egr;i)max of the elements in each part (i). Then, the tentative selections of the shape of the rubber composite, the shape of each part (i) and the physical properties of the rubber material, and the calculations by the finite element method are repeated until an allowance ratio Sia calculated as a ratio of strain (&egr;i)b at break to the maximum strain (&egr;i)max becomes equal to a specified reference allowance ratio S0 or higher in all of the parts (i).

Abstract: A golf ball whose core is covered with a cover, wherein the core is constituted of a rubber composition containing polybutadiene rubber and the cover is constituted of a resin composition composed of ionomer resin and diene rubber. A golf ball cover material composition composed of ionomer resin, diene rubber and non-staining antioxidant. A method of manufacturing a golf ball cover material composition constituted by mixing/kneading ionomer resin and diene rubber.

Abstract: A golf ball whose core is covered with a cover, wherein the core is constituted of a rubber composition containing polybutadiene rubber and the cover is constituted of a resin composition composed of ionomer resin and diene rubber. A golf ball cover material composition composed of ionomer resin, diene rubber and non-staining antioxidant. A method of manufacturing a golf ball cover material composition constituted by mixing/kneading ionomer resin and diene rubber.

Abstract: A pneumatic radial tire has at least two belt layers disposed at a tread portion thereof, wherein the two belt layers are constituted by inclining a strip formed by aligning a plurality of reinforcing cords to a tire circumferential direction and extending it zigzag in the tire circumferential direction so that the strip is turned back from the lower belt layer to the upper belt layer at both end portions of the two belt layers, and zone portions in which the reinforcing cords incline to the right in the tire circumferential direction and the zone portions in which the reinforcing cords incline to the left in the tire circumferential direction are alternately arranged.

Abstract: A pneumatic vehicle tire having a belt layer at the outside of a carcass layer of the tread, wherein a plurality of mutually parallel reinforcement cords are wound back and forth in a spiral at a predetermined angle to the longitudinal direction and embedded in a matrix of a lateral flattened tubular cross-section to form a continuous tape and the continuous tape is continuously wound around the outer circumference of the carcass layer a plurality of times in a spiral to form the belt layer or a pneumatic vehicle tire having a continuous tape, composed of a two-layer construction consisting of a plurality of aligned rubberized reinforcement cords wound in a spiral to form a lateral flattened tubular cross-section and an elastic cord inserted inside the flattened tube along its longitudinal direction as a core member, continuously wound over an outer circumference of a carcass layer at a tread in a spiral with a slight angle with respect to the tire circumferential direction to form a belt layer.

Abstract: A pneumatic radial tire includes a cylindrical steel cord belt layer having a two-layered structure is formed by winding a tape obtained by burying one or a plurality of steel cords in parallel with one another in a matrix, round the outer circumference of a carcass layer on a tread while bending the tape zigzag.

Abstract: A pneumatic radial tire is formed by disposing a single steel cord belt layer on the outer side of a carcass layer in a tread, and providing a cylindrical organic fiber cord belt layer of a double structure on the outer side of the steel cord belt layer by winding a tape, which is obtained by burying one or a plurality of organic fiber cords in parallel with each other in a matrix, around the steel cord belt layer while bending the tape zigzag.

Abstract: A pneumatic radial tire formed so that, when the tire is inflated from a non-inflated state, in which the inner pressure thereof is 5% of a normal lever, to a normal inner pressure, a central region of the outer surface of the tread in a meridional cross section of the tire which is between two points P.sub.1, P.sub.1 ' spaced from the center P.sub.0 of a tread width to left and right along the outer surface of the tread by a distance L, which is expressed by the formula 0.25TW.ltoreq.L<0.50TW, with respect to a width TW of a ground contacting portion of the bread grows outward in the radial direction of the tire, shoulder regions on both outer sides of the two points P.sub.1, P.sub.1 ' contracting inward in the radial direction of the tire, with a radius of curvature R.sub.2 of a region, which is formed between two intermediate points P.sub.2, P.sub.2 ', which are positioned halfway respectively between the center P.sub.

Abstract: A pneumatic radial tire for heavy loads, having steel belt layers provided on the inner side of a tread, and a tread pattern having a plurality of divisional ribs separated by a plurality of main grooves extending in the circumferential direction of the tire, characterized in that at least the inner vertical surfaces of left and right outermost main grooves out of the main grooves are formed so as to extend zigzag in the circumferential direction of the tire, narrow grooves which extend continuously in the circumferential direction of the tire being provided at the shoulder side edge portions of ribs internally adjacent to the outermost main grooves, the width W.sub.4 of the narrow grooves being set to a level in the range of 0.

Abstract: A pneumatic radial tire for heavy-duty vehicles in which reinforcement belts comprising metal cords are disposed in the tread portion, and a plurality of main grooves extending in the circumferential direction of the tire are provided in the tread surface. In addition, recessed and projecting portions are provided on the edges of the tread surface in a zig-zag fashion along the circumferential direction of the tire.

Abstract: A pneumatic radial tire comprising a carcass layer, a tread portion and a belt layer disposed therebetween, the belt layer having a structure composed of at least two layers, wherein the belt layer is formed at least at a central portion of the cross section thereof to have a parallel portion substantially parallel to the axis of rotation of the tire over a width corresponding to 30 to 50% of the maximum width of the belt layer; and the carcass layer is formed in such a manner that when the tire is mounted on a rim and filled with air to 10% of a normal internal pressure, a portion corresponding to the parallel portion of the belt layer has a profile of a carcass line joined parallel to the parallel portion and a portion tangentially extending from the edge of the parallel portion and leading through the maximum width portion of the tire to at least the upper edge of a bead filler has a profile of a carcass line comprising arcs having substantially the same radius of curvature.

Abstract: A heavy duty and medium pneumatic radial tire having a belt layer composed of at least three layers between a carcass layer and a tread, wherein the first belt layer as numbered from the carcass layer towards the tread is separated into two parts at the central region of a crown and at least one organic fiber cord layer is disposed in a space formed by the separation of the first belt layer.

Abstract: A radial tire with a split structure in the first belt layer provided with an organic fiber cord layer in the split structure and having a narrow groove extending in the circumferential direction of the tire and provided in each of both shoulder portions of the surface of a tread, wherein the narrow groove has a depth h determined in the radial direction of the tire, and a distance d.sub.1 measured between the internal edge on the shoulder side of an opening portion of the narrow groove and the radially outermost surface of the shoulder portion as determined along a parallel line to the surface of the tread, and a distance d.sub.2 measured between the internal wall surface on the shoulder side of the bottom of the narrow groove and the radially outermost surface of the shoulder portion as determined along a parallel line to the surface of the tread, wherein d.sub.1 is less than 15 mm and is smaller than d.sub.2, and a shape factor m defined by the following equation is 0.8 to 1.