GB1101341A - Improvements relating to connecting linkages for pivoted hand levers - Google Patents

Abstract

1,101,341. Agricultural implements. NATIONAL RESEARCH DEVELOPMENT CORPORATION. 6 Nov., 1964 [9 Aug., 1963], No. 31646/63. Heading A1B [Also in Division F2] In raising a tool-carrying bar 20 of the agricultural tractor of Specification 972,920, the pivotal movement of an actuating lever 30 is transmitted to the bar 20 initially by a flexible cable or chain 34, connected to the lever 30 at a point 36 adjacent its pivot 31, and, after predetermined angular movement of the lever 30, with a lower mechanical advantage, by a second cable or chain 33, previously slack, connected to the lever 30 at a point 35 at a greater radius from the pivot 31 than the point 36, the chain 34 then becoming slack. As the lever 30 approaches its extreme position (Fig. 5, not shown) in which it may be held by a hook (44), the mechanical advantage increases again. The chains 33, 34 are connected at a ring 37 to a strut 38 pivoted at 39 to the tractor frame 23, to which later the lever 30 and arms 22 carrying the member 20 are also pivoted at 31 and 24 respectively. A chain 40 connects the ring 37 to a bar 41 secured to the arms 22.