| 摘要 |
<p>1,259,539. Power-screwdrivers. ALFRED TEVES G.m.b.H. 22 Sept., 1969 [28 Sept., 1968], No. 46641/69. Heading B3N. [Also in Division G3] An air operated screw-driver comprises a plate 3 having lobes 16, secured for rotation with the tool shaft 15, two pairs of nozzles 1, 2, formed in a body 11 fixed to the tool body 17, the nozzles 1 being on one side of the plate, and nozzles 2 being on the other side, nozzles 1 being connected to a supply 12, and nozzles 2 being connected to nozzles 13, which latter are connected to the main air control valve via a logic circuit-Fig. 3 (not shown). In operation, when the tool, and therefore plate 3, rotates, a jet of air is supplied alternately to a nozzle 13. When shaft 15 is brought to a standstill, a continuous signal is supplied to one of the nozzles 13 so that the main air control valve is actuated, and the supply of air to the logic circuit and to the tool drive is interrupted.</p> |
