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:
Oct. 14, 1980
Filed:
Nov. 29, 1978
Eric J Hurst, Trenton, CA;
Hugh G MacAulay, Batawa, CA;
Bata Shoe Company, Inc., Belcamp, MD (US);
Abstract
In a slush molding process for producing a boot or shoe from a plastisol, a mold in the shape of the article of footwear is filled with liquid plastisol, the mold is heated to form a skin, the mold is tilted to pour out excess plastisol, and, after filling the heel cavity of the mold, the skin and heel filler are cured or hardened, and the skin is removed from the mold and trimmed for further processing. Instead of filling the heel cavities of the molds with a specially formulated heel filling composition, the skin trimmings, which were previously discarded as waste, can be ground, if necessary, mixed with additional stabilizer and injected into the heel cavities using an injection unit. With the molds travelling along a straight line path of travel, it is necessary to cause the nozzle end of the injection unit to move in synchronism with the molds. For such purpose, the injection unit is mounted on a shaft which is rotated by a drive train connected to the conveyor chain carrying the molds or the drive of the conveyor chain. In order to cause the nozzle of the injection unit to follow the same straight line path of travel as the molds, the shaft and injection unit are mounted on a carriage slidable towards and away from the molds, and a cam device controls sliding of the injection unit so that the nozzle is maintained in position over a mold during each heel filling operation. By utilizing the waste material instead of a specially formulated heel filling material, the cost of producing the heel and consequently the cost of the article of footwear as a whole is substantially reduced.