| 摘要 |
1,236,827. Making bolts; jointing. PLASTIC METAL PRODUCTS CORP. 12 Sept., 1968 [28 Sept., 1967], No. 43390/68. Headings B3A and B3V. [Also in Division F2] A method of making a bolt comprises threading one end of a straight shank 10, disrupting the continuity of the surface of the other end of the shank, placing on the latter end of the shank a head 14 having an axially recessed shoulder portion 18, and applying external radially inward forces against the shoulder to cause the metal thereof to flow into the surface disruptions thereby permanently affixing the head to the shank. The surface disruptions may comprise knurling 22 or longitudinal fluting (34), Fig. 5 (not shown). The shoulder 18 is formed to a hexagonal or square cross-section as the head is being secured to the shank. The shank is made from steel rod and the bolt head is preferably formed by die casting, being made from any desired metal, e.g. iron or ferrous alloys, zinc, brass, copper, steel or aluminium. |
