To suppress the breakage of coil springs of a valve actuator, and to reduce the size of the valve actuator.
The valve actuator opens and closes a valve by the contact/separation movement of a first spring seat 14 and a second spring seat 32. The valve actuator includes the first coil spring 51, the second coil spring 52 and an intermediate spring receiver 60. The intermediate spring receiver 60 includes: a first spring receiving unit 62 at which an opening penetrated with the second coil spring 52 is formed, and which sandwiches the first coil spring 51 between the first spring seat 14 and itself; a second spring receiving unit 64 which is positioned inside the first coil spring 51, and sandwiches the second coil spring 52 between the second spring seat 32 and itself; and a connection 66 which is positioned between the first coil spring 51 and the second coil spring 52, and integrally connects the first spring receiving unit 62 and the second spring receiving unit 64.
| WO/2007/069526 | VALVE ACTUATOR |
| JPS51131922 | SLIDE VALVE CONSTRUCTION |
| JP6758717 | Vacuum valve |
SASA OSAMU
KINOSHITA SO
| JPH09100940A | 1997-04-15 |
| US3039758A | 1962-06-19 |