GB424764A - Improvements in and relating to lifting jacks and the like - Google Patents

Abstract

424,764. Lifting-jacks. HERN, A. B. F., and HERN, A. H. F., 8, Essex Street, Strand, London. Aug. 18, 1933, No. 20306. [Class 78 (iii)] [See also Group XXXI] Comprises improved forms of lazytongs jacks which may be portable or attached to a vehicle, may be operated by screw-and-nut mechanism or by hydraulic or compressed-air devices, and may collapse into a box or casing or may be enclosed within a waterproof bag. As shown diagrammatically in Fig. 1, the lazytongs 1, 2, 8, 9, 11, 12 is stabilized by levers 14, 15 with rollers 16 engaging the guide 4, and the crutch 13 is guided by a link 17. In a modification, Fig. 2, (not shown), the upper diamond is dispensed with and the crutch is mounted at the pivot 10 and guided by a link such as 17. As shown in Fig. 3, the control is replaced by a plate 13<a> pivoted to the links 8, 9 and guided by rollers 16<a> on the extended links 14, 15. As shown in Fig. 4, the lazytongs 18-24 is stabilized by rollers 16 running on the guide 4 and the crutch is guided by the link 25. As shown in Fig. 5, the lazytongs is guided by a link 26 and vertical guide 27, and the crutch is guided by a link 17. As shown in Fig. 6, the lazytongs 32, 33, 8, 9, 11, 12 is carried on crossed levers 28, 29 pivoted on the base at 30, 31 and is stabilized by a vertical guide 27, and the crutch is guided by a link 17. In a modification, Fig. 7, (not shown), the upper diamond is dispensed with and the crutch is mounted at the pivot 10 and guided by a pair of equal links pivoted to the links 8, 9. In all these arrangements, the screw-and-nut or fluid-pressure operating device may be arranged in other positions, e.g. adjacent to the base or upper plate, the hydraulic cylinder may be vertical, the screw may have a single or double thread and may comprise right-and-left hand portions, the screw may turn on a ball thrust bearing, it may be driven by bevel-gearing, or it may be fixed from rotation and the lazytongs operated by a nut driven by toothed gearing. When the jack is attached to a vehicle, the mechanism is inverted, and the operating device is provided with a handle shaft which may be detachable, may be connected with the jack by a universal joint, and may be connected at its other end with the vehicle by a clip if required to be released for working or by a sleeve if required only to be rotated, and the handle shaft may be secured, as by a pin, against movement due to the vibration of the vehicle.