Improvements in or relating to Tracked Vehicles

1,177,460. Endless-track vehicles. CHELYABINSKY ORDENA KUTUZOVA I STEPENI, ORDENA KRASNOI ZVEZDY, TRAKTORNY ZAVOD. 7 Aug., 1968, No. 37680/68. Heading B7H. In an endless-track tractor having equalized track frames 1 pivotally connected to the tractor chassis and provided with sprung ground support rollers 6, each track frame 1 carries at one end a spring-suspended idler wheel 5. Each idler wheel 21 is carried by an arm 15 splined to a sleeve 10 journalled by bearings 24, 25 in a support member 14 slidably mounted in the frame 1. A laminated torsion bar spring 11 within the sleeve 10 has respective ends anchored to the sleeve and support member 14. An extension 16 of the arm 15 co-operates with an additional spring 18 providing a progressive spring rate, and with a screw 17 adjustable to raise the idler wheel 21 from a ground support position consistent with maximum tractive effort to a non-support position consistent with maximum running speed. Side thrust on the idler wheel is transmitted directly to the support member 14 through adjustable stops 41 engaging the idler wheel axle 23, and from the member 14 to the track frame 1 through adjustable thrust pads 39, 40.