Abstract: A cord reinforcing layer 30 can be highly efficiently fanned with easy control, and the amplitude and the wavelength of a wavy steel cord 32 can be made uniform throughout the cord reinforcing layer. When the wavy steel cord 32 (ribbon-like body 37) is wound plural times around the forming drum 35 to form the cylindrical cord reinforcing layer 30, the amount of extension is made decreased with distance from a set position P of a bead core 12 in the axial direction, and the amount of extension applied in advance to the wavy steel cord 32 in the vicinity of the set position P is approximated to the amount of extension according to the expansion and deformation of the wavy steel cord 32 at a position spaced away from the set position P, whereby at least either one of the amplitude and the wavelength of the wavy steel cord in the tire can be made uniform throughout the cord reinforcing layer 30.

Abstract: A tire molding apparatus folds the periphery of bead portions at a low speed with an increased pressing force. The tire molding apparatus has folding mechanisms including fingers to fold the tire component to the periphery of bead cores. Folding fingers (101) are integrally provided with cams (120), which rotate in accordance with the swing of the fingers. The fingers (101) receive a driving force of a driver (130) through cam followers (122) energized by springs and the cams (120), and open. The cams (120) are rotated in accordance with the opening of the finger, compressing the springs energizing the cam followers (122). The compression of the springs reduces the opening speed of the fingers (101), and increases the pressing force of finger rolls (104) applied to the tire component (K).

Abstract: When a stitching roll is allowed to act on a tread rubber member to attach the tread rubber member to an unvulcanized tire, lateral displacement of the tread rubber member is prevented. In a method for manufacturing unvulcanized tires by attaching a tread rubber composite (40) to an unvulcanized tire (55), the tread rubber composite (40) is disposed on the outer circumference of the unvulcanized tire (55) that is disposed on the molding drum (50) and is swelled into a toroidal shape, and, while the molding drum (50) is rotated, a rotating stitching roll (45) is pressed against a tread rubber member (42) of the tread rubber composite (40) to press-bond it to the unvulcanized tire (55). At this time, the outer-peripheral rotation speed of the stitching roll (45) is controlled such that it is substantially equal to the outer-peripheral rotation speed of the above-described tread rubber member (42).

Abstract: A tire manufacturing method includes the steps of, when a green tire is molded, moving a toroidally expandable toroidal molding drum through a distance between a plurality of working stations at a specified tact time, disposing a carcass band and both bead cores on the drum in any working station and locking the bead cores, increasing the diameter of the molding drum, toroidally extending the carcass band between both bead cores, and rolling up the side portion of the carcass band around the bead cores in the outer radial direction, assembling tire component members with the bead cores locked to the toroidal molding drum and molding the green tire, and reducing the diameter of the molding drum, unlocking the bead cores, and removing the green tire from the molding drum, whereby the tires of a plurality of sizes can be sequentially molded, a conventional tire structure must not be largely changed, and an energy and time can be prevented from being wastefully consumed.

Abstract: A pneumatic tire comprises a carcass comprised of at least one carcass ply containing a steel cord(s) arranged at a cord angle of 70-90° with respect to an equatorial plane of the tire and toroidally extending between a pair of bead cores and turned up around the bead core inward or outward in a radial direction to form a turnup portion, wherein a wrap part wrapping on a peripheral face of the bead core therealong is formed in the turnup portion of the carcass ply.

Abstract: A ribbon-like element supplied from a supply source is wound on the rotating toroidal support member, when a first rotatable guide roller arranged spaced from the outer surface of the support member is moved in parallel with the meridian direction along the outer surface of the support member, and turned so that the direction of its rotational axis approaches a tangent relative to the outer surface of the winding member. A second guide roller is arranged on a straight line perpendicular to a plane containing the moving trajectory of the first guide roller and passing through the first guide roller, and has a rotational axis that extends in the widthwise direction of the ribbon-like body extending from the supply source toward the winding member.

Abstract: The present invention aims at improving balance and uniformity of a tire, with simplifying facilities, reducing space for the facilities and suppressing shape flows and generation of air bubbles. An extruder is provided for supplying rubber ribbon immediately after extrusion to a second molding drum, so that the rubber ribbon is spirally wound around the second molding drum plural times to structure a portion of tread (a cap layer), whereby the rubber ribbon which is relatively hot and soft is wound around the second molding drum. As a result, the rubber ribbon easily deforms compliant to the second molding drum. Further, no joint portion of starting and terminal ends as is observed in the prior art exists, whereby thickness of the tread is even in the circumferential direction.

Abstract: A tire comprising a tread layer comprised of a tread rubber and an electrically conductive band arranged in a widthwise middle portion thereof, and a method of producing the tire, wherein the tread rubber is made of a low-conductive continuous rubber ribbon circumferentially wound plural times, and the electrically conductive band is made of a high-conductive thin annular rubber sheet. Also, the electrically conductive band is arranged so as to extend in the widthwise region ranging from a part of the top face of the first tread rubber portion to a part of the bottom face of the second tread rubber portion, whereby the tire uniformity is improved and the production is possible in a multi-size mixed production system and the conductive path from the belt to the treading face can be surely formed at a low cost.

Abstract: Tire building drum and tire building method, capable of assembling tire component members with high accuracy. A tire building drum is used, which includes at least one core body, which is disposed at an axial inside of a pair of bead lock means, and which comprises a plurality of sheets of rigid support members disposed in a toroidal shape and adapted to be displaced and thereby expanded or contracted. Bead cores are locked by the bead lock means, respectively, and a center portion of a carcass band is bulged while displacing the bead lock means close to each other. Back side portions of the carcass band are folded to radial outsides around the bead cores, respectively. The core body is then radially expanded to the maximum diameter while locking the bead cores, and tire component members are assembled onto the radially expanded core body.

Abstract: Precise measurement of the entire surface of a green tire is performed during a building process. A laser displacement gauge is provided integrally on a bonding roller for bonding a ribbon to a building drum of a tire building apparatus, and the profile of a green tire after bonding the ribbon is measured while the ribbon is bonded. At this time, the displacement gauge is enabled to move in an X-Y plane and rotate in the same plane to change the orientation while the ribbon is bonded, so as to enable measurement of the entire surface of the tire. Then, the resulting data with respect to the Y-axis direction is corrected according to the difference in position between the bonding roller and the laser displacement gauge.

Abstract: A device for turning a carcass band is used for a method of producing a green tire which enable to securely wrap and hold end portions of a carcass band, which is to be wrapped around a bead ring, as desired without a need for restraining the end portions on the bead ring by means of an auxiliary restraining member or the like. In this device, anvil rings having diameters smaller than that of the rigid core are arranged adjacent to respective side portion of a rigid core having an outer contour corresponding to an inner contour of a product tire. The anvil rings are fixed on a rotational driving shaft of the rigid core, and are provided with two annular grooves on their circumferences. Rotation disks for pressing a carcass band into the annular grooves of the anvil rings are arranged so as to approach to and recede from the anvil ring.

Abstract: A method for manufacturing a tire and a tire curing mold, capable of preventing a failure that the turned-up portion is moved apart from the main portion of the carcass of a green tire on a rigid core, are provided. Each bead-holding ring to hold the bead portion 11 of a green tire 10 from the lateral outside, is assembled onto the rigid core prior to preheating the green tire 10.

Abstract: In a grinding device, first, an eddy-current-sensor detects a distance from the eddy-current-sensor to an outer peripheral surface of a belt layer while a tire to be retreaded held by a pair of half rims is caused to rotate. Thus, an eccentricity amount and an eccentricity direction of the tire to be retreaded with respect to a device axial center, corresponding to the phase of the tire to be retreaded, can be respectively determined, so position control signals corresponding to the phase, eccentricity amount and eccentricity direction of the tire to be retreaded can be generated. Next, on the basis of the position control signal, a carriage causes a rasp to be moved in a radial direction with respect to the tire to be retreaded along the radial direction whose center is a device axial center, and the rasp grinds a tread surface of the rotating tire to be retreaded.

Abstract: A method of manufacturing a tire having first color characters or lines on at least one side wall part, includes the steps of stamping a second color side wall rubber and a first color side wall rubber on the side face of a carcass member formed in a toroidal shape by winding, a plurality of turns, a continuous second color rubber ribbon and a continuous first color rubber ribbon thereon, stamping a second color cover rubber on the outsides of the side wall rubbers by winding a rubber sheet whereon one turn in an annular shape, and molding a green tire, whereby the use of a large extrude can be eliminated, different types of tires can be efficiently manufactured since a size switching can be easily performed, the accuracies of the shape and the dimensions of the members thereof can be increased, the uniformity and the tire balance thereof can be increased, and the sharp profile of the first color characters or lines can be assumed, thus eliminating problems associated with the appearance.

Abstract: A pneumatic tire having a portion formed by laminating a rubber ribbon exhibits improved durability due to reduced propagation of cracks from the surface of the laminated portion of the rubber ribbon at a sidewall, for example. A pneumatic tire includes a laminated portion (40) formed by winding and laminating a rubber ribbon (50), and a surface layer (41) formed by bonding a rubber sheet on the outer surface of the laminated portion (40) at, for example, a sidewall (31). The surface layer (41) covers projections, recessions, and portions of adhesion failure on the laminated portion (40), and smoothes the surface of the tire, thus preventing cracking from propagating from the surface of the tire by tensile forces (P) and compressive forces (Q) during flexure.

Abstract: In producing a side-reinforced type runflat tire in which side reinforcing rubbers with generally crescent-shaped sections are interposed between a carcass and an inner liner, the first drums 11a, 11b on which the side-reinforcing rubbers are to be attached are so configured that their diameter do not substantially fluctuate along the axial direction. The expanding operation of the first drum, the mutually approaching operation of the first drums 11a, 11b and the approaching operation of the bead gripping rings 30A are synchronized. As a result, there is provided a tire and a method of its production capable of being produced by a multi-size mixed flow production system consisting of minimum equipments and of preventing air inclusions and wrinkles between the carcass member 4A and the side-reinforcing rubber 2A.

Abstract: The present invention aims to improve the durability of a motorcycle pneumatic tire in which a tread portion is formed by a rubber strip-laminating body and to provide a method of producing such tire. A pneumatic tire 1 for a motorcycle has a tread portion 5 consisting of a rubber strip-laminating body 8 formed by continuously and spirally winding a rubber strip 11 in the tire circumferential direction. An imaginary extended plane p of an outermost layer 10a of the rubber strip-laminating body 8 forming the surface 9 of the tread portion defined by extending a boundary between the rubber strips constituting the outermost layer from the surface 9 of the tread portion to the outside of the tire is situated in a tread end side with respect to a normal line n of the surface 9 of the tread portion.

Abstract: A method for extruding a rubber strip for tire constitutive members, allowing the facility to be made compact and having excellent energy efficiency, and a strip rubber extrusion system for carrying out the method. In the method for extruding a rubber strip for tire constitutive members according to the invention, the rubber to be extruded from an extruder (1) is warmed-up by a gear pump type warming-up machine (2) and directly fed to the extruder (1).

Abstract: A tire molding apparatus folds the periphery of bead portions at a low speed with an increased pressing force. The tire molding apparatus has folding mechanisms including fingers to fold the tire component to the periphery of bead cores. Folding fingers (101) are integrally provided with cams (120), which rotate in accordance with the swing of the fingers. The fingers (101) receive a driving force of a driver (130) through cam followers (122) energized by springs and the cams (120), and open. The cams (120) are rotated in accordance with the opening of the finger, compressing the springs energizing the cam followers (122). The compression of the springs reduces the opening speed of the fingers (101), and increases the pressing force of finger rolls (104) applied to the tire component (K).

Abstract: A shaped rubber body with improved uniformity in terms of weight and/or physical properties is produced by extruding a rubber strip by a positive displacement extruding system that includes, as seen from an upstream side of the rubber strip, a screw extruder unit, a gear pump unit and an extrusion head unit with an extrusion nozzle, which are connected in series with each other. The rubber strip is fed to a rotating support along a substantially straight passage extending from the screw extruder unit to the extrusion nozzle of the extrusion head unit, passed through a gap defined between a pair of pressure roll, and applied onto an outer surface of the support by one of the pressure rolls.