| 摘要 |
At the valve closing position of a valve element 17, a valve stem 16 is stopped by contracting a engaging portion 71 provided in an intermediate portion in the axial direction to a stopper 70 formed on a valve body 10. Since the valve element 17 forms a bleed port forming a small clearance between the valve element 17 and an orifice 12, a small amount of fluid flows through the clearance even at the fully closing position of valve, and thus so-called initialize noise, which is liable to be produced, for example, at the time of the start of compressor, can be reduced. Since the valve stem 16 is stopped by the stopper 70, the bleed port is less liable to wear. The movement in the valve closing direction at the time when a screw feeding member 45 is further driven by a stepping motor 40 is absorbed by a coil spring 52. Subsequently, by the contact of upper and lower stopper bodies 67 and 68 with each other, the rotation base point of the stepping motor, which is the zero point flow rate, is secured. |
