CUT-OFF VALVE AND CUT-OFF VALVE BLOCK EMBEDDING CUT-OFF VALVE FOR SECURING SUFFICIENT VALVE CLOSING AIRTIGHTNESS

摘要

PURPOSE: A cut-off valve and a cut-off valve block embedding the cut-off valve are provided to obtain proper valve-closing airtightness even if enlarging the diameter of a valve body to correspond to the large quantity of fluid by reducing the gradient of the valve body. CONSTITUTION: A cut-off valve is composed of a valve body(43) for moving to open and close a passage(41) and having a through-hole; a valve seat(42) pressurized with the valve body to close the passage and fixed and disposed in the passage; a first spring(49) for pressurizing the valve body to the valve seat; a valve shaft(45) with the thickness blocking up the through-hole; a pin(45a) integrally formed at one end of the valve shaft, inserted into the through-hole from the opposite side of the valve seat, and formed with a bypass passage between the pin and the through-hole; a second spring for pressurizing the valve shaft toward the valve seat; a guide unit(48) for guiding a movement of the valve shaft; a rotary driving mechanism(55) disposed oppositely to the valve seat of the valve body; a transfer unit(60) installed at an output shaft(59) of the rotary driving mechanism; a movable body(61) for pressurizing and operating the pin and the valve body and having a central hole thread-combined to the transfer unit; and a rotation preventing unit(64) for restricting the rotation of the movable body.