| 摘要 |
PURPOSE:To save electric power consumption in a vacuum type air control system holding constant pressure in an actuator, by flowing no electric current in a negative pressure selector valve device when a control valve is in a neutral state. CONSTITUTION:If a rotary sensor 1 detects a higher value than a preset value, a comparator circuit 3 generates an indicating current with one of the lead wires 36 to a plus side and the other to a minus side, and a permanent magnent magnet 27 is operated rightward by an electromagnetic coil 24. A valve body 34 is separated from a seat 17b to transmit the atmospheric air from an inlet port 19 to a chamber 10 through a chamber 21 and outlet port 20, and a control valve 13 is moved to the direction of closing a bypass passage 16' and operated to hold a preset value of the comparator circuit 3. If the comparator circuit 3 detects a lower value than the preset value, the magnet 27 is operated leftward to separate a valve body 31 from a seat 17a and transmit megative pressure to the chamber 10 through a passage 9 from an inlet pert 18. Accordingly, the control valve 13 is moved to the direction of opening the bypass passage 16' to limit a feed amount of air to a combustion chamber B. |
