GB376731A - Improvements relating to portable lifting jacks - Google Patents

Abstract

376,731. Lifting-jacks. ROSE, W. and PRECISION METAL WARES, Ltd., 179, Belgrave Road, Birmingham. April 7, 1931, No. 10170. [Class 78 (iii).] A ratchet jack of the kind having pawls e, d set for lifting and lowering by a displacement of the lever handle in its socket is constructed with toothed racks a<2> on the jack body, and the operating lever fulcrums alternately on the lifting pillar c to raise or lower the pawls e and on the fulcrum of the pawls e to raise or lower the lifting pillar c and pawls d carried thereon. The operating handle g is inserted in a socketed member f and is provided with recesses k<2> co-operating with balls or plungers j so that by sliding or turning the handle g in the socket, blade springs k, k<1> can be set to the inoperative position shown for lifting or can be held outwardly from the socket to engage the pawls for lowering. The' member f is pivoted in the lifting pillar c at f<2> and carries main pawls e pivoted at e<2>. The pillar c carries a bracket c<1> with holding pawls d pivoted at d<2>. For lifting, during the downward stroke of the handle the lever f<2> pivots at e<2> while the pawls d ride upwards on the racks a<2>, and during the upward stroke the load is carried by the pawls d while the lever pivots at f<2> and the pawls e ride upwards on the racks. When the handle g is set for lowering and the blade springs k are held outwards away from the member f they engage the tails of the pawls d, e in turn so that on the downstroke of the handle the pawls d are withdrawn from the racks in readiness to engage the next lower teeth when the handle is first raised, and the pawls e are then withdrawn from the racks in readiness to engage the next lower teeth when the handle is first lowered. A casing mover the pawl mechanism is flanged at m<1> to engage a stop l on the jack body and limit the upward movement of the pillar.