Abstract: A method of electro-hydraulic control of the cutting and self-advancing mine-roof support units in an automated longwall is carried out in dependence on the measured lengths to which the rams pushing the support are extended, with extraction by the cutter occurring in long cuts extending over almost the entire length of the longwall. After each extraction cut, the conveyor is advanced by an amount equal to the depth to which the cutter has cut, and the process of advancing each group is triggered in dependence on the length to which the pushing rams have been extended. The self-advancing roof-support units inserted in the longwall are divided into groups which, depending on the respective state of operation, are moved forward individually and successively, in each case by a preset extension length of the pushing rams.
Type:
Grant
Filed:
August 11, 1989
Date of Patent:
October 23, 1990
Assignee:
Herman Hemscheidt Maschinenfrabrik GmbH & Co.