The Goodyear & Tire Rubber Company

Kumho & Co., Inc.

Robert P Loser

Terry John Waibel

Ronald L Loeffler

Michael W Smith

Georges V Adam

Arthur Allen Goldstein

Joseph M Forney

Deborah L Ebbott

William R Casey

Jang S Kim

An elastomeric tread for a pneumatic tire is disclosed. The tread has a pair of ribs, one rib being adjacent each lateral edge of the tread, and a plurality of large block elements located between the ribs. The large block elements are in two rows extending circumferentially about the tread. The ribs and the two rows of blocks are separated by three circumferential zigzag grooves. The blocks are further separated by a plurality of lateral grooves. The lateral grooves extend from one rib to the opposite rib.

Tread for a tire with blocks and ribs

Tire tread

Vehicle tire

Pneumatic tire tread and buttress

A radial-ply pneumatic tire carcass has a reverse curvature, an outwardly concave shape, centered about the tire's equatorial plane. A wedge of elastomeric material is positioned above or below the belt structure of the tire. If positioned above the belt structure, the wedge is used with a carcass cord angle in the range from 65.degree. to 80.degree.. This carcass structure also may be used when the wedge is positioned between the belt structure and carcass. The tire has an aspect ratio less than 75%, but 40% to 65% is preferred. The wedge has a shape on its radially inner side that is similar to a low amplitude cosine function. Particularly when the wedge is above the belt structure (providing both it and the belt structure with a reverse curvature), the belt cord angle is less than a 'critical angle' of about 25.degree.. The invention can provide a radial-ply belted tire which has 'natural shape' in the portion of the radial carcass underlying the belt structure, but the 'natural shape' is for those low cord angles used in the belt structure.

Radial ply pneumatic tire with reverse curvature carcass ply

Tire

A tire carcass (55) is built on a generally cylindrical drum (10) rotatable about an axis (12) by applying green tire components (50) to the cylindrical surface (14) and curved shoulder surfaces (32,34) of the drum (10). The radially inner surfaces (58) of the lower sidewalls (56) of the tire carcass (55) are formed on the surfaces (32,34) of the curved shoulders (28,30) which have a curvature which can be generated as a segment of a conic section which is at an angle other than a right angle to the axis of a cone. The curvature for each of the lower sidewall inner surfaces (58) as measured along a line of intersection (36) of a shoulder surface (32,34) of the drum (10) and a radial plane (A--A) containing the drum axis (12) is decreased from positions (38) adjacent the axially outer edges (40) of the drum (10) to positions (42) on the cylindrical surface (14 ) of the drum. As a result, there is minimum change in the shape of the lower sidewalls (56) during shaping of the tire carcass (55) to the cured shape of the tire.

Tire building apparatus and method

A pneumatic tire (A) includes a body having a crown (10) with a ground-engaging tread portion (20), a pair of sidewall portions (12, 14), as well as a pair of bead portions (16, 18). An annular substantially inextensible bead reinforcing member (36) is positioned in each of the bead portions (16, 18). A carcass ply (30) is positioned in each sidewall (12, 14) and the crown (10) and extends from one of the bead portions (16) to the other of the bead portions (18). A first elastomer reinforcing member (50) is positioned in each bead portion (16, 18) and is disposed axially outwardly of the carcass ply (30) and adjacent the bead reinforcing member (36). A second elastomer reinforcing member (60) is positioned in each bead portion (16, 18) with at least a portion of the second member being disposed axially inwardly of the carcass ply (30) and extending radially outwardly from adjacent the bead reinforcing member (36).

Pneumatic tire with sidewall insert

Growing community of inventors

Akron, OH, United States of America

Robert P Loser