Longwall mining apparatus
AssigneeDowty Mining Equipment Limited
InventorRobert G. Harris
Life of this patent
Estimating the term…
Abstract
Mining apparatus for use on a mineral face comprising a plurality of roof supports arranged along the face, the roof supports being capable of undergoing advancing movements in sequence, and a manually operable control means on each of at least some of the supports, arranged such that actuation of the control means on one support will enable any other support within a predetermined range of supports adjacent said one support to undergo an advancing movement if the support preceding the said support in the sequence has unergone an advancing movement, the number of supports between any two successive supports which have a control means being less than the number in said predetermined range.
Claims11
Mining apparatus for use on a mineral face comprising a plurality of roof supports arranged in a line along the face, advancing means for each support, an advance prime signal generating means on each support adapted to generate an advance prime signal on completion of a support advance movement, an advance prime signal transmission means between each adjacent pair of supports adapted to feed an advance prime signal only to a support adjacent to the advance prime signal generator giving the prime signal, a plurality of manually operable controls one on each of some or all of the supports, each of which on actuation is adapted to generate an advance enable signal, advance enable signal transmission means extending between all supports connected to receive and to transmit any advance enable signal, and limiting means associated with the enable signal transmission means adapted to ensure that any advance enable signal may not be carried by said enable signal transmission means for more than a predetermined number of supports from the position of generation of an advance enable signal, each said advancing means being adapted to cause advance of the associated support only on receipt of an advance prime signal and an advance enable signal, said predetermined number of supports being less than the number of supports along the face, and the number of supports between any two successive supports having manually operable controls being not more than said predetermined number.
Dependencies are inferred from the claim text.