Hisashi Machida

トラクションドライブ式無段変速機の変速制御 : 第2報,ねじ制御式CVTの変速特性

Traction-drive continuously variable power transmission, CVT, changes its speed ratio through control of the side-slip force acting on the Hertzian ellipse. Usually it is controlled by a hydraulic servomechanism because of its easy control of equal torque transmission of rolling elements. Here a new type of mechanical servomechanism is proposed for reducing the auxiliary unit power waste. Side slip for the speed ratio change is controlled by a nut and screw set. The dynamic model of the servomechanism is reduced to a first-order lag system. The time constant is inversely proportional to the screw-lead and the disk rotational speed. The performance is tested by the CVT with input torque capacity of 38N·m, input rotational speed of 4000 rpm and speed ratio range of 0.4 to 2.5.

ハーフトロイダル形トラクションドライブ式無段変速機の研究 : 第4報,4輪駆動用CVTの設計と効率試験

Authors have been developing single-cavity half-toroidal-type CVTs, continuously variable power transmissions, for the past 14 years and recently have designed a new type of double cavity CVT for a 4 wheel drive automotive power transmission. This CVT easily distributes transmitting torque between front and rear axles without center differential gears. This report presents the configuration of the CVT of nominal input torque capacity 250 N·m and maximum speed ratio 1 : 8.7, and shows the power transmission efficiency.