GB662961A - Improvements in or relating to hydraulic apparatus - Google Patents

Abstract

662,961. Balancing-apparatus. GENERAL ELECTRIC CO., Ltd., and MEACOCK, J. H. March 8, 1950. [March 8, 1949] No. 6316/49. Class 78 (ii). In hydraulic apparatus for raising a load, e.g. aircraft in aircraft carriers, in whicb a platform is raised and lowered by a piston, or ram, and cylinder arrangement, the platform and load are at least partially balanced by compressed gas, such as air, operating with a subsidiary piston, or ram, and cylinder arrangement hydraulically connected with the first-mentioned piston, or ram, and cylinder arrangement, raising and lowering of the load being arranged to be effected or controlled by means which aid or oppose the balancing effect of the compressed gas. The load carrying platform 3, Fig. 1, is supported by a ram 2 movable in a cylinder 1 which is connected by a pipe 4 to subsidiary cylinders 5, 6. The cylinders 1, 5, 6 and pipe 4 contain water or other working liquid. Rams 7, 8 working in the cylinders 5, 6 are connected by a cross-head 9 on which are mounted rams 10, 11 working in cylinders 12, 13. These cylinders are connected by a pipe 14 to a series of compressed air bottles 15. Also mounted on the cross-head are opposed rams 16, 17 working in oil-filled cylinders. 18, 19 which are connected by a pipe 20 to an oil pump 21 of the variable displacement swashplate type capable of operating as a motor and driven by an electric motor 22. The air pressure and dimensions of the various parts are so chosen that the weight of the platform 3 and half the maximum possible load is approximately balanced. Each cylinder associated with the platform is connected to it by chains passed over sprockets and the sprockets are connected by shafting and bevel gears to ensure correct levelling of the platform. In practice the operating cylinders will move on fixed rams and more than one cylinder and ram, e.g. eight will be associated with each platform, and the cylinders will be connected to a pair of accumulators in each of which the oil cylinder is disposed between the balancing cylinders. In a modification, Fig. 3, the cylinder 1 is connected by a pipe 65 containing an oil pump motor 21 to the left hand end of a cylinder 67 containing a piston 68. The right hand end of the cylinder is connected to the air bottles 15. This arrangement may be modified by disposing the cylinder 67 vertically and in this case the piston 68 may be dispensed with and baffles provided to limit the agitation of the oil.