| 摘要 |
1,156,070. Jig washers. BETEILIGUNGSUND PATENTVERWALTUNGS G.m.b.H. 28 Dec., 1967 [4 Oct., 1967], No. 58855/67. Addition to 1,032,837. Heading B2H. In a gas-operated jig of the type described in the parent specification, instead of stepwise adjustment of the change in volume of the hollow body (3-5), and hence of the length of the jigging stroke, by the alternative utilization of two lower limit switches (12, 13) which limit the contraction in length of the hollow body, infinitely variable adjustment of the length of the jigging stroke is provided by interposing an adjustable delay member between a single lower limit switch and the means for varying the internal pressure in the. hollow body. The lower limit switch is arranged, through the delay device to effect simultaneous opening and closing of the inlet and outlet valves (14, 15) respectively. To ensure re-starting of the jig after stopping, the movable exciting element (7) of the jig switch is of .such length that it provides excitation even in its end position corresponding to maximum delay. Alternatively, the switch may be connected to an emitter of an electrical starting impulse. |
