Apparatus for manufacturing fluid seals

Abstract

Various forms of apparatus are described for manufacturing half seal units by injection molding in specially constructed molds. The apparatus was developed in response to a need for producing precision parts, particularly so-called insert molded parts containing integral stiffening members surrounded by an elastomeric seal body. Seals of this type are mated upon installation in position of use to form a unitary seal which provides primary and secondary seals as well as a seal at the split line where the two half seals are joined. One described molding apparatus includes means adapted for formation of a mold cavity from horizontally movable, cam actuated mold parts wherein finished so-called piece parts are removed after molding by an axial movement with a specially constructed stripper assembly. Another described apparatus is adapted for injection molding of an elastomer in totally surrounding relation to a metal insert, following which the newly formed piece part is removed by sequential downward movement of plural separable mold parts. Flow of the elastomer in its uncured state is carried out so as to eliminate or minimize the formation of flash, or at least confine it to areas wherein formation thereof will not prove objectionable in the finished piece part, the molds are adapted to permit utilization of vacuum assistance for complete filling, and means are provided for automatically tear trimming the completed piece parts upon stripping thereof from the mold cavity.