| 摘要 |
<p>PURPOSE:To simplify a structure to achieve miniaturization and cost reduction and to enhance assembling workability, by allowing a valve for opening and closing a discharge port discharging the pressure medium sent into a pressure storage part to perform opening and closing operations by the action of the coil spring wound around the rotary shaft of a motor. CONSTITUTION:The pressure medium of a pressure medium chamber 16 is sent to the arm band of an examinee from an emitting port 13 through the hose inserted in an insert port 7 to measure blood pressure. After the blood pressure is measured, a motor 2 is reversed in the direction shown by an arrow C. The friction force between a rotary shaft 21 and the inner peripheral surface of a coil spring 4 acts in the direction tightening the spring 4 and the force ready to rotate along with the rotary shaft 21 acts on the coil spring 4. Since this force is stronger than that at the time of forward rotation, a valve 3 is opened from a permanent magnet 5 to open a discharge port 15 and the pressure medium is rapidly discharged. Since the coil spring 4 loosens upon the reception of pressing force in a loosening direction at the point of time when the end part 4b thereof impinges against the wall surface of a groove 18, the rotary shaft 2 races in the ring of the coil spring 4 in such a state that the valve 3 is held. The motor 2 can continuously rotate without almost receiving load.</p> |
