Bridgestone/firestone, Inc.

The Goodyear & Tire Rubber Company

Leonard R Holm

Gerardo P Elia

Gaetan Arbour

George T Watts

Daniel Christian Shavers

Douglas A Swift

Ivan Z Podobnik

Robert Dean Irwin

Robert Thomas Irwin

Arthur Warner Moll

Gary Wayne Corder

Nguyen Bau

Margaret N Elia

Ronald Thomas Dillard

Gilles Lavallee

A method and apparatusfor correcting tire nonuniformity is disclosed. The invention is particularly suited for correcting tread runout and connicity problems for large off-road tires. Multiple measurements are taken in multiple circumferentially spaced planes which enable data to be fed into a computer which predicts an optimal profile to correct tire non-uniformities using preset rules. A virtual template directs correction of the tire profile.

Method and apparatus for correcting tire nonuniformity

An extruder head made up of several segments including a first section made up of at least two plates bolted together. At least one plate is hingeably mounted to another plate in the first section to provide access to an extrudate passage defined by the plates. Downstream of the first section is a pair of mating blocks bolted to the first section further defining the extrudate passage. Inserts of hardened steel are provided and held by the plates and blocks forming the extruder head and the inserts define parts of the extrudate passage. A cooling liquid chamber is provided in at least one insert to cool the wall forming the passage. Although the passage is continuously restricted in the downstream direction, to increase the pressure of the elastomeric melt, intermittent portions of a slightly greater cross-sectional area are provided to allow expansion and thus intermittent lower pressure of the melt as it passes through the passage.

Extruder head for elastomeric material

An extruder for elastomeric material has an axial screw in an extruder chamber defined by a cylindrical housing. Two radial planes of vented kneading pins are provided upstream of the extruder housing succeeded by spaced-apart planes of non-vented kneading pins. Each vented kneading pin includes small apertures at the inlet end of the pin which communicate with a stepped bore of gradually increasing crosssectional area from the inlet to the outlet thereof whereby gases within the elastomeric material can be vented through the apertures communicating with the stepped bore to the exterior of the extruder housing.

Vented kneading pin for extruder

Growing community of inventors

Hartville, OH, United States of America

Leonard R Holm