Title:
VALVE OPENING AND CLOSING MECHANISM FOR VACUUM EXHAUST DEVICE
Document Type and Number:
Japanese Patent JPS5280517
Kind Code:
A
Abstract:
Disclosed is a vacuum valve apparatus comprising a valve head, a motor for driving the valve head, means for checking the position of the valve adapted to issue a first signal upon detecting that the valve head is moved to be within a predetermined valve-closed range, means for checking electric current adapted to issue a second signal when the driving current for the motor is increased to a predetermined value, switching means adapted to cut the driving current supply to the motor upon detecting said second signal, and means for issueing a third signal for confirming the complete closure of the valve when both of the first and the second signals are simultaneously obtained.
Inventors:
OKUMURA MASAHIDE
KAMAYA YOSHIO
NAKAIZUMI TAI
NAKADA TOSHIAKI
KAMAYA YOSHIO
NAKAIZUMI TAI
NAKADA TOSHIAKI
Application Number:
JP15506575A
Publication Date:
July 06, 1977
Filing Date:
December 26, 1975
Export Citation:
Assignee:
HITACHI LTD
International Classes:
F16K31/04; F04B37/16; F16K37/00; F16K51/02; (IPC1-7): F04B39/08; F16K31/02; F16K37/00
Domestic Patent References:
| JP40028316A | ||||
| JPS5074232A | 1975-06-18 |