V-벨트 무단변속기(無段變速機)를 이용(利用)한 자탈형(自脫型) 콤바인의 주행속도(走行速度) 제어(制御)(II) - V-벨트 무단변속기(無段變速機)의 변속특성(變速特性) -

A Forward Speed Control of Head-feed Combine Using Continuously Variable V-belt Transmission -Transmission Characteristics of CVVT-

This study was conducted to investigate the feasbility of continuously variable V-belt transmission(CVVT) as automatic power transmission system of combine harvesters. An experimental set-up for testing the performance of CVVT and the automatic transmission system was designed and used to analyze the power transmission characteristics of CVVT. The transmission efficiency of CVVT was increased logarithmically with increase of the load of driven shaft, but was not affected by the speed ratios of transmission. More than 80% of transmission efficiency was obtained in the 25N-m load and more of driven-shaft, and the maximum efficiency was 88~91%. When rapid speed change of the CVVT was attempted, the speed of driven shaft was stabilized within about 0.4 seconds after shift operation in both cases of increasing and decreasing of the speed.