| 摘要 |
1,041,895. Making grommets. UNITEDCARR Inc. Oct. 7, 1964 [Oct. 7, 1963], No. 40924/64. Heading B3A. [Also in Division F2] To form a grommet, Fig. 4, a disc of cold rolled steel is drawn in four operations to flanged cup shape and then the bottom is blanked out leaving a hole surrounded by a small inturned rim, Fig. 10. The flange is then cut to form bent fingers 7, Fig. 13, and a punch and circular die is used to bend the fingers so that they extend radially to their outer portions which incline downwardly from shoulders 8. The body then is forced over a die to flare the holed end, curl back its edge compressing the rim against the body wall to form a bead 5 and produce a curved flange 4. The flange 4 is placed in a die and the legs 7 are then bent to lie adjacent the grommet body, Fig. 4, and at the same time the flange 4 is curved back further towards the legs 7. The grommet is then hardened by heat treatment. |
