Patent GB-1073358-A (GB)
Title: A method and apparatus for controlling machines,especially mining machines, which comprises winding devices
IPC: E21C29/16
Filed: 1964-08-04
Abstract: 1,073,358. Mineral-mining installations. GEBR. EICKHOFF MASCHINENFABRIK U. EISENGIESSEREI m.b.H. Aug. 4, 1964 [July 25, 1963], No. 30509/64. Heading E1F. [Also in Division F2] In apparatus for controlling mining machines wherein a winding device is driven by hydraulic motor 3 and pump 1 in a closed working circuit 4, 4' connected to a control circuit supplied with liquid from a servo pump 2, pressure responsive valves cause pump 1 to cease to deliver liquid and so stop motor 3, when pressure in the working circuit rises to a predetermined value and/or when pressure in the control circuit falls. Pumps 1, 2 are driven from the motor of the mining machine. Liquid from pump 2 passes via pipe 8, 9 13 and valve 11 to move a piston 14 whose end 16 engages grooves 15 in a slide 17 to adjust pump 1 to idle in which it prevents any liquid flow and thus holds motor 3 stationary. Liquid also passes to valve 21 via pipes 13, 19, 20 and via pipe 24, valve 26 and pipe 27 to move piston 28 against spring 29. A plunger 30 is thereby free so that a lever 31 can rotate rod 32 to shift valve 11 through roller 34. Pipe 9 is closed and pipe 13 is connected to sump. Liquid now acts via pipes 8, 35, 37 to withdraw piston 14 from slide 17 and valve 21 is connected to pipe 8 via pipe 38. A handle 40 can now be rotated to move a bar 44 and slide 17, Fig. 3, via nut 47, threaded spindle 43, gears 41, 42; bar 44 moves valve 21 via lever 50 to supply liquid via duct 57 or 58 to one end of a piston 53 which adjusts pump 1 to the desired direction of rotation and output and since lever 50 is connected to piston 53, the valve 21 is eventually returned to its shown position. Pump 1 forces liquid through pipes 4 or 4' to drive motor 3. According to the direction of rotation of pump 1 liquid is supplied to one end of valve 63 via pipes &c. 60 or 60', 61 or 61', 62 or 62' to push valve 63 so that liquid acts via space 65 and pipe 66 on a piston 67 of a performance regulator 68 to move its extension 69 into groove 15 to adjust pump 1 to a lower output when the pressure in the working circuit exceeds a predetermined value. If the winding device is overloaded or underloaded a piston 71 is caused to engage groove 15 to lower the pump output. Liquid from the working circuit also acts via pipe 72, recess 73 and bore 74 on a piston 76 to raise valve 26 against spring 77 if there is an excess pressure in the working circuit, the valve cutting off supply to piston 28 which moves lever 32 away from valve 11 which thus moves to supply liquid to piston 14 so stopping the output of pump 1. When the working circuit pressure drops valve 26 returns to its initial position permitting piston 28 to be raised; lever 31 can then cause pump 1 to operate. Should the pressure be very high, the edge 79 of valve 26 enters recess 80 to short circuit the working circuit through pipes 81 and 82 or 82' and also to cut-off piston 28. Cooled and filtered liquid is supplied to the working circuit via pipes 24, 84 or 84' and check valve 83 or 83' and an equal volume is removed, in dependance on the position of valve 63, via pipe 60 or 60', recess 61 or 61', pipes 82 or 82', 81. recess 80, pipe 85 to valve 86, cooler 87 and the sump.