| 摘要 |
<p>An improved adjustable box wrench having a mouth (9) with a plurality of gripping surfaces (27, 31, 32) for surrounding a nut, bolt or the like. A movable jaw (5) allows the size of the mouth to be altered when a worm screw (8) is turned. The worm screw (8) has gear (24) which fit between teeth (20) in an arm (4) extending from the movable jaw (5). The adjustment arm (4) and worm screw (8) fit into cavities (14, 17) in the wrench body (1). Increased lateral support for the movable jaw is provided by protrusions (19) on each side (21) of the jaw which fit into and move longitudinally within channels (26) in fixed gripping surfaces (32) on opposite sides of the mouth (9). A removable closure plate (6) covers the adjustment arm (4) and the worm screw (8) and facilitates assembly of the wrench and disassembly for repair or other purposes.</p> |
