GB548671A - Improvements in and relating to elevating apparatus - Google Patents

Abstract

548,671. Portable fluid-pressure hoists. BROMILOW & EDWARDS, Ltd., and SWIFT, H. W. May 8, 1941, No. 5977. [Class 78 (iii)] Hoisting apparatus for use with aircraft and for other purposes comprises a gang of wheeled trolleys 1 each provided with a vertical ram cylinder 2, a self-contained hydraulic system on each trolley and unitary control means, which may be remote from the trolley, adapted to operate the systems to raise and lower the rams either together or independently of each other. When used for lifting aircraft three trolleys may be used as shown in Fig. 4, all being controlled from a remote point, as by means of control buttons 36, 39 mounted on a body harness 35 and connected to a general control unit 40 on one of the trolleys. In the construction shown in Figs. 1 and 2 the trolley is mounted on three castor wheels 9 and its ram cylinder is provided with three stays 7. The ram or piston is preferably telescopic and is formed with a ball-head 20 to engage a suitable socket on the underside of one of the aeroplane wings. A trolley for lifting the tail of the aircraft has its ram provided with a pivoted fork member instead of a ball to engage the tail. Each trolley has a petrol engine or electric motor 14 driving a pump 18 connected to a tank 19 and the ram cylinder 2. Hand-operated screwjacks 27, 28 are provided on each trolley to take the weight off the castor wheels and prevent accidental moving of the trolley. The portable switchboard 35 has independent switches 36, 37, 38 for each of the three hoists and a master switch 39 for simultaneously controlling all three motors. It may also have means for controlling the lowering valves of the hoists. in the case of the trolley having a petrol-engine or other source of power a common hydraulic system may be used connected by fluid-pressure pipe lines to the cylinders of the other trolleys in the gang.