BELT TYPE CONTINUOUSLY VARIABLE TRANSMISSION

PURPOSE:To prolong the service life of an endless V-belt by reducing the friction torque generated between the endless V-belt and the fixed pulley half body and movable pulley half body of a trailing side variable diameter V-pulley smaller than that of the residual part in the outer peripheral part of these both pulley half bodies. CONSTITUTION:When the load applied onto a trailing shaft 2 exceeds the transmission torque even if the speed change ratio is in low ratio, in other words when the radius of the contact part of a drive side variable diameter V-pulley P1 of an endless V-belt 3 is close to the min. value, and the radius of the contact part of a trailing side variable diameter V-pulley P2 for the V-belt 3 is close to the max. value, the revolution torque of a driving shaft 1 is not transmitted to the trailing shaft 2. At this time, between the trailing side variable diameter V-pulley P2 having a large friction torque and the belt 3, the outer peripheral part having a small friction force of the fixed and movable side pulley bodies 30 and 31 contacts the belt 3, and slipping state is generated therebetween. Therefore, the belt 3 is not in a standstill state, and freely moves between both pulleys P1 and P2, and the generation of local friction is prevented.