GB1191802A - Improvements in Jacks - Google Patents

Abstract

1,191,802. Jacks. TANGYES Ltd. 30 April, 1969 [11 April, 1968], No. 17708/68. Heading B8J. A lifting jack comprises a pair of arms 10, 11 pivotally connected by a pin 12, respectively with ground engaging wheels 41, 52, the former on a shaft 40 and the latter on an axle 51 carried by a pair of downwardly divergent arms 15 forming the arm 11. A load engaging pad 20 is dished and is pivoted at one end to the arms 15 through lugs 21 and pin 22. The other end of the pad 20 runs on a roller 31 on a pin 32 attached to the arm 10. A screw threaded member 42 slides through an opening in the shaft 40 and has an eye 43 secured to it by a pin 45. The inner end of the eye 43 bears against a thrust bearing 46 and the member 42 is threaded through a nut 58 held against rotation relative to a bracket 56 against which it bears. Limbs 54 of a tie frame are riveted to the bracket 56 at one end and have holes at the other end through which the axle 51 passes. A second nut 60 is a safety feature supporting the load if the nut 58 strips. The jack is raised by rotating the member 42, using a handle assembly, Fig. 5 (not shown), having a universal joint, so as to draw the wheels 41, 52 relatively together, thus raising the pad 20 by a scissors action. The screw-threaded member 42 may be rotated by an electric, hydraulic or pneumatic motor. Alternatively the member 42 and the nuts 58, 60 may be replaced by an hydraulic ram. In the lowered, inoperative position, Fig. 1, the jack is of considerable length. It may be folded by lifting the pivotally connected ends of the arms 10, 11 so that they lie side-by-side with the pairs of wheels 41, 52 in contact. The frame 55 may be replaced by a flexible assembly incorporating chains or cables.