| 摘要 |
<p>1,082,663. Hydraulic rams. W. E. & F. DOBSON Ltd. Jan. 14, 1965 [Jan. 18, 1964], No. 2312/64. Heading F1P. The supply of hydraulic fluid to a horizontal ram cylinder 1 for advancing a coal face conveyer is cut-off at the end of the outward stroke by the closure of an electric switch 4 or a pilot valve effected when a coil spring 17 carried by the piston 16 moves a cam slide 9 carried by the cylinder end block 12 to displace a plunger 6 also in said block 12 and connected to the switch 4. A similar switch 3, plunger 5 and cam slide 18 carried by the opposite cylinder end block are actuated by a spring-biased striker 24 carried by the piston 16.</p> |
