Sheet metal pulley with force fitted hub - is in re=entrant cylindrical sleeve which is preserved by holding annular wheel zone during formation of rim

摘要

The pulley-wheel with an integral hub is fabricated from thin sheet metal, and the hub-piece (2) is force-fitted into the sheet metal element (1). The hub (2) is retained in a re-entrant co-axial sleeve (3) which is formed by an initial pressing operation. The grooved rim (7) is formed by subsequent pressing and profiling operations during which the piece is clamped by an intermediate annular zone (5). The utilisation of this zone (5) ensures the dimensional integrity of the sleeve (3). The dimensions of the sleeve (3) and the hub-block (2) are such that the force-fitting provides a rigid connection without recourse to crimping or brazing. The process may be concluded by folding a locating tongue (8) into a groove (9) in the hub (2). The folding may be effected simultaneously with the force-fitting or immediately thereafter.