| 摘要 |
<p>1,110,831. Advancing hydraulic mine roof supports. COAL INDUSTRY (PATENTS) Ltd. Dec.17, 1965 [Dec.22, 1964, No. 52029/64. Heading F1P. The main hydraulic supply line 9, Fig.1, of a plurality of sequentially advanced mine roof supports 1 - 5 each comprising props 1a - 5a, rams 1b 5b and control valves 1c - 5c includes an electric flowmeter 11 connected to a remote flow-rate indicator 14, Fig. 2, and through an integrating unit 17 to a total flow indicator 18 and which are actuated on pushing a switch button 15 to energize a solenoid valve 1d of the first support 1 and initiate the cycle. The end unit 5 has transducer 5e, 5f connected to indicators 19, 20 respectively for measuring the advance of ram 5b and the pressure in prop 5a.</p> |
