GB1131067A - Improvements in and relating to lifting jacks for vehicles - Google Patents

Abstract

1,131,067. Screw jacks. M. STORZ, and W. PLISCHKE. 10 Dec., 1965 [12 Dec., 1964], No. 52498/65. Heading B8J. A lifting jack, Figs. 1, 2, for vehicles, comprises a support column 20 mounted on a base (not shown) with a load-carrier 22 arranged on the column 20 for lifting and lowering by a threaded spindle 24 driven by a crank handle 34 through bevel gears 32, 28 arranged in a headpiece 26 and is characterized by stopping means 42, 44 which prevent further drive of the spindle 24 in a predetermined position of lift of the load carrier 22. The stopping means 42, 44 comprise an attachment 42 on the crank handle 34 which contacts an abutment 44 on the load carrier 22, as it approaches the region of its upper lifting position, further rotation of the crank handle 34 becoming impossible. The stopping means may comprise a cam 48, Fig. 5, which co-operates with an extension 56 on a load carrier 54, Fig. 4 (not shown), to prevent further rotation of a crankpin (50) at maximum lift. As shown in Fig. 6 a rocking lever 60 pivoted to a load carrier 58 is deflected into the path of a crank 66 at maximum lift. As shown in Fig. 7 an abutment for blocking a crank 80 is provided by a spring-loaded slide 70 associated with a displaceable locking bolt 74. As shown in Fig. 11 a crankpin 102 is driven by a crank 98, a tilting lever 90 forcing the crank 98 off the crankpin 102 as a load carrier 110 approaches its upper lifting position. A friction clutch adjusted to the maximum torque permissible may be interposed in the transmission means for driving a crankpin (108), Figs. 12, 13 (not shown).