Cosmetic or dental brush manufacture involves insertion of a bristle-free end of a brush through an opening with variable cross-section into a tool for molding a handle

摘要

A carrier part of twisted wire sections has a head end with bristles(3) and a bristle-free opposite end around which a brush handle is to be molded. The bristle free end is inserted through a variable size opening(7) of a tool part(4) into an injection molding tool. For the injection stage the cross-section of the opening is reduced to hold and seal around the end of the brush preform(5). Following injection the opening cross-section is increased to allow the brush to be removed. The tool part(4) is divided close to the opening. Opening cross-section is reduced by moving tool slides(15a,15b) and increased by moving them apart. An independent claim is also included for the process equipment which includes an injection molding tool for molding a handle onto a bristle-free handle end(6) of a brush preform and includes a tool part with an opening of variable cross-section.