GB179720A - Improvements in haulage gear for slip-ways - Google Patents

Abstract

179,720. Glover, W. G. Feb. 26, 1921. Winches; driving-gear; brakes. - Haulage gear for slipways is constructed with the downhaul drum 7 on the same shaft as the main drum 1. The haulage rope passes from the main drum to the upper end of the cradle carrying the vessel, while the downhaul rope passes from the lower side of the cradle, round a pulley at the bottom of the slipway, to the downhaul drum. When the loaded cradle is being raised, the drum 7 is loose to pay out the downhaul rope freely, but when the vessel is to be launched, the drum 7 is clutched to the shaft by a friction or dog clutch 39. The driving motor 23 is reversed so that the drum 1 pays out, while the drum 7 supplies the initial force to start the cradle moving downwards. When the cradle is started, the drum 1 is disconnected from the motor so that it pays out under the load and drives drum 7 to take up the slack of the downhaul rope. To permit accurate winding and paying- out, the drum 7, using a thinner rope, is made slightly larger than the drum 1 so that the distance from the centre of each drum to the axis of the ropes is the same. The driving-gear includes sliding toothed wheels arranged for two lowspeeds, each speed being obtained by a train comprising four pairs of meshed wheels. A solenoid brake mechanism 30 is applied to the motor shaft, while brake blocks controlled by screw-operated linkages 35, 38 are applied to each drum. In a modified construction the drum 7 is cast in two halves and arranged between two drums 1 driven by separate motors so that It can be clutched to either drum shaft. The driving-gears can be cross-connected so that either or both motors can drive either drum 1, or either can drive the drum 7.