Motor operated valve

摘要

The invention provides a motor-operated valve including a planetary gear mechanism achieving a greater reduction gear ratio without increasing the number of teeth of the gears, thereby enabling downsizing. In a planetary gear mechanism 1, a sun gear 91 functioning as an input gear receives smaller load than an internally toothed output gear 45, so gears (second planet gears 95) having a smaller module are connected to the planet gears 93, and the sun gear 91 is in engagement with the second planet gears 95. The sun gear 91 is formed of a same module as the second planet gears 95. The rotation of the sun gear 91 is reduced in speed and transmitted to the second planet gears 95, and rotation of the second planet gears 95 rotated at a reduced speed is further reduced by the slight difference in the numbers of teeth of the ring gear 44 and the internally toothed output gear 45 before being output.

主权项

1. A motor-operated valve comprising:
a motor composed of a rotor and a stator; a valve member being moved toward and away from a valve seat formed on the valve body; and a planetary gear mechanism comprising: a sun gear; one or more planet gears in engagement with the sun gear; an internally toothed fixed gear in engagement with the planet gears; and an internally toothed turning gear in engagement with the planet gears; wherein each planet gear is composed of a first planet gear in engagement with the internally toothed fixed gear and the internally toothed turning gear, and a second planet gear which is formed integrally with the first planet gear and having a smaller module than the first planet gear; and the sun gear is in engagement with each second planet gear, wherein the rotation of the rotor is transmitted to the sun gear, and the internally toothed turning gear is connected to the valve member.