The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 13, 1979
Filed:
Feb. 15, 1977
Achille Gallizia, Milan, IT;
Industrie Pirelli, S.p.A., Milan, IT;
Abstract
A process is provided for molding a tread on a vehicle tire body in which a tire body requiring a tread is supported in a mold which combines with the surface of the tire body to form a cavity conforming to the configuration and dimensions of the tread. The cavity is filled with a flowable vulcanizable elastomeric composition by injection at equally spaced points around the equatorial axis of the mold of measured volumes of material which will combine to fill the cavity and develop a low pressure in the mold cavity to insure flow of material until the cavity is completely filled. The invention also provides an injection molding apparatus having a mold which combines with a tire body supported therein to form a cavity corresponding to the configuration and dimensions of a tire tread. A series of equally spaced openings are provided around the equatorial axis of the mold for injection of molding composition and openings are provided around the sides of the mold cavity for the escape of air from the cavity as it is filled with composition.