摘要 |
<p>A series of electric valve drive units is provided, which can set up rotational efficiency and anti-counter-rotating function of a valve. In a series of electric valve drive units which can drive a valve body via reduction gears, at least one gear mechanism of the reduction gears is provided with an eccentric wobbling inscribed gear type of a planetary gear mechanism which has an input shaft, an external gear eccentrically and wobbly rotating about the input shaft, an internal gear engaged with the external gear, and a carrier absorbing a wobbling ingredient of the external gear. At least two types of valve drive units are supplied, one of which places prime importance on the anti-counter-rotating function, and the other places prime importance on the rotational efficiency.</p> |