Flow rate adjustment valve, and fluid control apparatus in which the flow rate adjustment valve is used

A flow rate adjustment valve including:

• a body provided with a fluid passage;
• a valve element configured to open and close the fluid passage;
• a vertically movable body that moves upward or downward whereby an opening degree of the fluid passage is adjusted, the opening degree of the fluid passage being defined by the valve element;
• a rotation member that is screwed on the vertically movable body;
• and a rotation device configured to rotate the rotation member thereby causing the vertically movable body to move upward or downward, wherein
• the rotation device comprises a driven gear disposed at a part of the rotation member, a driving gear engaged with the driven gear, and a motor configured to rotate the driving gear, and
• the motor is a stepping servo motor and has a rotary shaft to which the driving gear is fixed.