Patent ID: 8632649

Claim:
A method of fabricating a pneumatic tire for forming a tread portion by winding spirally a rubber strip member in a circumferential direction of a tire in a partially overlapping fashion, comprising: by an extruding machine, extruding continuously a rubber strip member whose cross section is divided into a first region which is made up of a conductive rubber and a second region which is made up of a non-conductive rubber, and winding the rubber strip member on to a rotational support element while changing an area ratio of the first region relative to a cross section of the rubber strip member in a tire width direction, wherein the rubber strip member made up of only the non-conductive rubber is used at a time of starting winding the rubber strip member and at a time of finishing winding the rubber strip member, wherein the rubber strip member made up of the conductive rubber and the non-conductive rubber is used in the midst of winding the rubber strip member, wherein in the extruding step, the extruding machine forms the conductive rubber into the shape of the first region and the non-conductive rubber into the shape of the second region and then coalesces the conductive rubber and the non-conductive rubber together to form the rubber strip member whose cross section is divided into the first region and the second region, wherein the rubber strip member is extruded in such a manner that an area ratio of the first region in both side portions in the tire width direction becomes larger than in a central portion in the tire width direction, wherein a base rubber portion is wound on the rotational support element in advance before the rubber strip member is wound on the rotational support element, and wherein the base rubber portion includes a base portion made up of a non-conductive rubber material and a conductive rubber layer made up of a conductive rubber material.