| 摘要 |
<p>1,230,539. Impact wrenches. ATLAS COPCO A.B. 17 Sept., 1969 [24 Sept., 1968], No. 45759/69. Heading B3N. An impact wrench comprises an anvil 19, Figs. 1, 2, a rotatable hammer 24, and a clutch dog 33, non-rotatably, but axially fixed, to the anvil member, the dog having a cam 37 slidable in a recess 35 in the anvil, and engageable with impact faces 45, 46 on the hammer, and a face cam 40 which co-operates with a ball 29. In a modification, sleeve shaped dog 48, Fig. 9, has three cams 49, and is splined to anvil 19. In a further modification, sleeve shaped dog 48, Fig. 10, is guided on a spacing sleeve 60 mounted on a spigot 55. In operation, a reversible pneumatic motor drives shaft 17, Fig. 1, which drive is transmitted to anvil 19, by ball and cam 29, 40, and dog 33. When the workpiece is screwed down, anvil 19 and dog 33 are retarded; hammer 24 continues to rotate, ball 29 co-operates with cam 40 to move dog 33 to the left, Fig. 1, against springs 42, whereupon cam 37 and co-operating face 45 or 46 produces rotary impacts to anvil 19.</p> |
