Abstract

An effective, relatively inexpensive, improved caster support structure can be manufactured by molding an appropriate polymer, preferably polypropylene, around a retainer forming a part of a conventional bearing into the shape of a housing. The housing is preferably shaped so as to include an elongated first cylinder which is coaxial with a second cylinder of greater diameter than the first. The bearing is located within a cavity at the end of a second cylinder remote from the first cylinder and is held in place because the portion of the retainer adjacent to the end of the second cylinder remote from the first is of smaller diameter than at least another portion of the retainer. The retainer is held against movement in such a way that it cannot be displaced by the shape of the retainer and housing and by a compressive type force resulting from a polymer orientation. The internal structure of a polymer necessary to exert this force is developed within the polymer as a result of cooling of the polymer material from a temperature at which it will flow during molding to ambient temperature.