Patent ID: 7090735
Filing Date: 2006-08-15
Classification: B29D,B60C,Y10S

Abstract:
1. A method of manufacturing a pneumatic tire, comprising: providing a circumferentially extending tread pattern of a pneumatic tire with at least first and second circumferentially extending ribs, said ribs being located on opposite sides of a mid-circumferential plane of said tire, each rib containing a plurality of tread blocks separated by laterally extending grooves, said tread blocks having sipes, said tread blocks having leading and trailing sidewalls symmetrical with respect to a first radial plane passing through a midpoint of said tread blocks and through an axis of rotation of the tire; varying an angle of inclination of the sipes with respect to a second radial plane passing through an outermost surface of the tread block and adjacent to the sipe and through an axis of rotation of the tire to change a residual aligning torque of the pneumatic tire until a desired residual aligning torque is achieved and such that an angled sipe is formed in each of the tread blocks, each angled sipe extending for a sipe lateral width and a radial depth at a substantially constant sipe angle of inclination between 2° and 15° with respect to the second radial plane passing through the outermost surface of the tread block and adjacent to the sipe and through the axis of rotation of the tire; wherein all sipes within said rib tread blocks on a first side of the mid-circumferential plane extend, at a first sipe angle of inclination with respect to said second radial plane for the sipe lateral width and the radial sipe depth, at least one sipe within each tread block on the first side of the mid-circumferential plane extending from one side of the block and across the center of the block to the other side of the block, wherein all sipes within said rib tread blocks on a second side of the mid-circumferential plane extend, at a second sipe angle of inclination with respect to said second radial plane that is substantially equal to and opposite the first sipe angle for the sipe lateral width and the radial sipe depth, at least one sipe within each tread block on the second side of the mid-circumferential plane extending from one side of the block and across the center of the block to the other side of the block, and forming a pneumatic tire such that said pneumatic tire has said angled sipes in said tread pattern.