GB433198A - Apparatus for lifting vehicles - Google Patents

Abstract

433,198. Vehicle &c. jacks. HALL, F. H., Cleeve Cottage, Holford, near Bridgwater, Somerset. Jan. 11, 1934, Nos. 1038, 2022, and 26519. [Class 78 (iii)] [See also Group XXXI] A fluid - pressure lifting-jack is operated by the explosion or combustion of gas-producing material. The Figure shows a cylinder 1 attached by clips 3 to a vehicle axle 2 and adapted to be moved relatively to the piston 4 by the firing of a cartridge 18 in the chamber 9. The gas produced first forces the piston 4 downwards until its foot 5 rests on the ground and then forces the cylinder upwards to raise the vehicle. A spring 6 normally maintains the piston and cylinder in collapsed position. A pawl 41, pivoted at 38, engages the slot 35 and holds the load in the raised position as long as a cam 42 contacts with the roller 46. To lower, a pull on the cable 47 rotates the cam about the pivot 43 and allows the load to overrun the pawl. In the chamber 9 a screw-on cap 23 carrying the firing-pin 33 confines the cartridge in the perforated cage 14. Unscrewing the cap slightly allows the gas to leak past the copper washer 16 to the exhaust outlets 26. Reference is made to the use of cartridges with two or more compartments containing different mixtures having different rates of combustion in order to produce a graded increase of pressure either continuous or in relays. Among the modifications referred to, the cap 23 may be hinged, or the firing-chamber may be fitted directly on the end of the cylinder ; the jack may be portable instead of attached to the vehicle, or the piston may be attached to the axle instead of the cylinder; two or more cartridges may be used to supply each cylinder, or a single cartridge may be used to raise two or more cylinders ; a safety valve may be fitted to the cylinder, and in some cases the pawl sustaining-gear may be omitted.