GB1169361A - Improvements in Fluid Valve Means for Mine Roof Supports - Google Patents

Abstract

1,169,361. Advancing mine roof support controls. W. E. & F. DOBSON Ltd. 28 Nov., 1966 [14 Sept., 1965], No. 39088/65. Heading E1P. [Also in Divisions EF2 and G3] A valve device is applied to an arrangement for extending and contracting hydraulic mine roof supports 13, 14, 15, and for advancing the supports by a cylinder-and-ram 24, 25. The device replaces in part a known arrangement in which there is a basic control block 1b, Figs. 1-5. (not shown) to which is fitted a manual control block 1a with manual valves (V, V1) controlling the supports and the advancing ram locally. In the present arrangement, the basic block is retained, and this includes throughway passages comprising a main feed passage 4a, a return passage 5b, and service passages 7, 8, 9 to the props, along with pressure holding and overload valves such as 16 and 52, 53, 54. A second valve. block fixed to the basic. block contains main fluid feed, return, and service passages registering with those in the basic block. The second valve block also contains a double seated cone automatic selector valve device 29b, 29c controlling the passages. This is operated by a control pressure signal received through a passage such as the passage 65 which extends from an outer surface of the block and supplies pressure through a fixed hollow stop 35 to move the valve members 29b, 29c apart. A third valve block 3 fixed to the second block is interchangeable and is arranged to provide alternatively for operation (a) in sequence with other supports by transmitted pressure signals, (b) remotely by electrical control, through a solenoid valve incorporated with the block, or (c) by a local manual valve. In each case, the third block has a pressure signal passage 41 registering with the passage 65 in the second block. As shown, the block 3 is arranged for operation in mode (a) the pilot pressure signal being received at a connection 41. An output signal to the support next to be: operated goes from a connection 44. The solenoid valve (97) Fig. 22 (not shown) communicates with an alternative signal passage 90 in the second block.