| 摘要 |
1,226,860. Power tong assembly. BYRON JACKSON Inc. 6 Sept., 1968 [17 Oct., 1967], No. 37744/70. Heading B3N. The jaw assembly in a power tong having an outer ring 11 provided with cam surfaces 18, 19, for actuating gripping jaws 40 inwardly, upon relative rotation of the outer ring and the gripping jaw assembly G comprises, a pair of annular guide members 21, 22, defining a central opening, axially extending arms 23, 24, disposed bebetween the guide members in opposed relation and defining diametrically opposed radial openings 25, hollow jaw guides 28 carried by the guide members, the gripping jaws 40 reciprocable in the jaw guides into the opening, and cam followers 44 carried by the jaws and adapted to be engaged by the cam surfaces of the outer ring to force the jaws into the opening. The machine is as described in Specification 1,226,856. |
