Gate valve in which amount of squeeze of sealing material is controllable

摘要

{Technical Problem};To provide a gate valve that can control the amount of squeeze of sealing material according to each of situations, that is, under the in-manufacturing or during vacuum-maintaining state; thereby, the invented gate valve is capable of suppressing deterioration of its sealing material and lengthening the service life of the sealing material used therein.;{Solution to Problem};The gate valve 100 of the embodiment has the control device 11, which is comprised of the equipment control unit 12 that transmits an instruction either an in-manufacturing CLOSE instruction or a FULL CLOSE instruction and the storage means 13 that stores position date that corresponds to each of such instructions. The control device 11 receives either of such instructions and generates the position signal referring to the corresponding position data. The servo motor 4 of the driving device 2 receives the position signal and the rotative force of the servo motor 4, which corresponds to the received position signal, is translated into the movement of the activator 5. The sealing material 3 on the gate 1 is pressed against the valve seat 101 by the gate 1 driven according to each of the instructions and is maintained in the squeezed state.

主权项

1. A gate valve comprising:
a valve seat, a valve body arranged confronting said valve seat, a sealing material, a driving device that drives said valve body to said valve seat to press said sealing material against said valve seat so that said sealing material will be squeezed to establish sealing, and a control device connected to said driving device, wherein, with respect to said gate valve, said driving device is comprised of a servo motor and an actuator connected to said valve body to drive said valve body by applying linear-motion force generated by translating rotative force from said servo motor, said control device is comprised of an equipment control unit that transmits an instruction that is either an in-manufacturing CLOSE instruction or a FULL CLOSE instruction according to determination by related manufacturing equipment, movement of the actuator is controlled so that a squeeze amount in a first squeezed state of said sealing material at a FULL CLOSE position is larger than the squeeze amount in a second squeezed state of said sealing material at an in-manufacturing CLOSE position by movement of the actuator in an opening direction from said FULL CLOSE position, and a storage means that stores in advance a graphical relationship, in a graph, of CLOSE position data obtained from squeezing of the sealing material and gas leak amount data relating to any gas leak from between the sealing material and the valve seat, said control device receives either said in-manufacturing CLOSE instruction or said FULL CLOSE instruction, according to the determination by said related manufacturing equipment, from said equipment control unit, and generates an in-manufacturing CLOSE position signal or a FULL CLOSE position signal by referring to said graphical relationship of the CLOSE position data and the gas leak amount data stored in said storage means, said servo motor receives said in-manufacturing CLOSE position signal or said FULL CLOSE position signal, and the rotative force of from said servo motor, which corresponds to the signal received by the servo motor, is translated into the movement of said actuator, and said sealing material is pressed against said valve seat by movement of said valve body caused according to said in-manufacturing CLOSE instruction or said FULL CLOSE instruction and is maintained being in a squeezed condition.