PROCEDE ET DISPOSITIF POUR LA FABRICATION DE GALETS PAR UNE TECHNIQUE DE MOULAGE PAR INJECTION

摘要

A method and apparatus for manufacture of a rolling body directly on a bearing, comprising a hub, a roller sleeve, an annular portion joining the hub and roller sleeve, and reinforcing ribs on either side of the annular portion. Injected material fills the recesses for forming the reinforcing ribs from two directions: a primary flow radially inwardly directed from the mold portion for forming the roller sleeve and a secondary flow radially outwardly directed from the mold portion for forming the hub. The total cross-sectional area of the recesses for forming the reinforcing ribs is adjusted with respect to the circumferential cross-sectional area of the mold portion for forming the annular portion so that the fronts of the primary and secondary flows meet in the recesses. Pressure-release openings are arranged to communicate with the recesses at points in the area at which the meeting of the flow fronts occurs. The junctures resulting from the meeting of the flow fronts are thereby formed along the reinforcing ribs.