Abstract: A hydraulic control for a longwall support with a plurality of face support frameworks (1-3), which are adapted to be actuated in the sense of longwall support functions, in particular in the sense of the longwall support operations: robbing, advancing, and setting, comprises hydraulic control valves (8, 9) for each of the biasing elements, which are each arranged in close spatial relationship with the biasing elements, and subdivided into groups. Each group connects to a hydraulic pressure line (16), which extends over the longwall length of a plurality of face support frameworks, via a group connection line (18), which can be blocked by a group stop valve (20) as a function of the actuation of the control valves, specifically, when all control valves are not actuated and all biasing elements of the group are in a static state.

Abstract: An electrically controlled actuating element is arranged on a machine by a flange connection consisting of a mounting flange (4) and a machine flange (2), and is controlled by an electric control subsystem (6). Embedded in the mounting flange (4) in a predetermined geometric pattern is a plurality of electric switches (7.1-7.8, 8.1-8.8). Each switch is arranged in an electric circuit that connects to the control subsystem. In the machine flange (2), closing elements are arranged in some marking points of the geometric pattern in a geometric arrangement that is characteristic of the respective machine and associated to it. In an existing flange connection, the switches located in the respective marking points can be actuated by the closing elements. The control subsystem (6) of each consumer is provided with a memory (11), which stores the geometric arrangement of the closing elements that is characteristic of and associated to the machine.

Abstract: For an explosion-proof connection of two electric line ends (25, 26), the contact elements (27, 28) are accommodated in two tubes (1, 2), which can be joined in an explosion-proof manner. Each of the plug-in contact parts is axially secured in its tube by a radial projection (41) in the direction toward the end facing the other tube. At its line end, each of the tubes is closed by an end cap (42), which sealingly surrounds with a narrow outlet (44) the electric lines, including an insulation (43). The tube, in which the plug-in contact part with the contact pins is axially secured, extends beyond the tip of the contact pins, and has there an enlarged diameter, with which it surrounds the other tube (inner tube 1,3) with a narrow cylindrical gap (sealing gap 20).

Abstract: For an explosion-proof connection of two electric line ends (25, 26), the contact elements (27, 28) are accommodated in two tubes (1, 2), which can be joined in an explosion-proof manner. Each of the plug-in contact parts is axially secured in its tube by a radial projection (41) in the direction toward the end facing the other tube. At its line end, each of the tubes is closed by an end cap (42), which sealingly surrounds with a narrow outlet (44) the electric lines, including an insulation (43). The tube, in which the plug-in contact part with the contact pins is axially secured, extends beyond the tip of the contact pins, and has there an enlarged diameter, with which it surrounds the other tube (inner tube 1,3) with a narrow cylindrical gap (sealing gap 20).