Patent GB-312113-A (GB)
Title: Improvements in or relating to controlling mechanism for moving devices or apparatus, more particularly for winding, hauling, hoisting and like gear
IPC: B66B1/12
Filed: 1928-02-18
Abstract: 312,113. Davison, J. W., Perry, J. F., and Associated Electrical Industries, Ltd. Feb. 18, 1928. Fluid-pressure.-Mechanism for controlling the motion of moving devices, particularly winding, hoisting and like gear, comprises a manuallyoperable brake lever connected to brake gear for the purpose of moving a brake-operating member different amounts from zero to " full on " and automatic means which on the occurrence of one or more predetermined emergency conditions are adapted to operate the braking gear to apply the brakes irrespective of the position of said manually-operable lever, said means being adapted to be reset when the said emergency conditions have passed by the movement of the said brake lever to its normal full on " position. An arm of the manually-operable brake lever 800 is connected by a rod 805, crank 806, shaft 807, crank 810 and rod 811 to a member 812 which is pivoted to a cross-head 813 carried by the moving member 814 of a solenoid 815 and biassed by a weight 816. The member 812 is connected by a rod 817, crank 832, shaft 831, crank 830 to a floating lever 826 one end of which is connected by a rod 827 to a brake valve operating member 828 and the other end of which is connected by a rod 829 to the cross-head of the brake engine. An abutment for the end of the member 812 comprises a rod 820 slidably mounted in bearings 818, 819. A spring 824 keeps the rod in contact with a cam 821 driven by the winding drum or depth-indicator so that it makes one revolution while the cage travels from the top to the bottom of the shaft. The cranked end of a control lever 799 is connected by a link 798 to an arm 797 of a three-armed lever, the other arms 795, 794 of which are connected respectively to a rod 793 for operating a rheostat controlling the speed of the winding engine, and to a rod 792 associated with cam gear whereby the rheostat control may be modified, e.g. in accordance with the normal winding cycle. A switch in the circuit of the solenoid 815 is opened to de-energize it in cases of emergency, such as overspeeding, overwinding, overload, failure of the current supply with electric winding engines or failure of the oil or air pressure with fluid-operated braking systems. A switch 833 prevents the re-energization of the solenoid unless the lever 800 is placed in the " full-on " position A. During normal running the solenoid 815 is energized, and the member 812 can be moved about its pivot 813 by the lever 800 to actuate the brake engine valve. When an emergency occurs, the solenoid is de-energized and the member 812 drops until one end rests on the abutment member 820. The brake valve operating rod 817 &c. are then no longer under the control of the lever 800, but are actuated by the cam 821 to produce an appropriate retardation as described in Specification 301,338. Manual control of the brakes is restored by moving the lever 800 to " full-on " position, placing the lever 799 in " neutral " position, and closing the circuits manually. A manuallyoperable switch in the solenoid circuit permits the transfer of the control of the brakes to the cam when desired. The variable abutment may be replaced by a fixed abutment or by one that is manually adjustable.