Abstract: A vacuum actuator having a vacuum chamber and an atmospheric chamber separated from each other by a diaphragm, and an actuator rod connected at one end to the diaphragm and extending across the atmospheric chamber to the outside of the actuator so as to be connected to an object to be actuated. At least one annular solenoid coil is mounted on the upper surface of the upper wall of the case defining the vacuum chamber, with the axis of the solenoid coil extending substantially at a right angle to the axis of the actuator rod. A plunger of the annular solenoid coil is adapted to be moved in one and the other directions along the axis of the annular solenoid coil. The end of the plunger is adapted to be moved into and out of a control pressure chamber of valve case. A port for introducing a vacuum from a vacuum passage into the control pressure chamber and a port for introducing the atmospheric pressure into the same are formed in the valve case coaxially with each other.

Abstract: A vacuum actuator having a vacuum chamber and an atmospheric chamber separated from each other by means of a diaphragm, and an actuator rod connected at its one end to the diaphragm and extending across the atmospheric chamber to the outside of the actuator so as to be connected to an object to be actuated. An annular solenoid coil is mounted on the upper surface of the upper wall of the case defining the vacuum chamber, in such a manner that the axis of the solenoid coil extends substantially at a right angle to the axis of the actuator rod. A plunger disposed in the annular solenoid coil is adapted to be moved in one and the other directions along the axis of the annular solenoid coil. The end of the plunger is adapted to be moved into and out of a valve case in which is defined a control pressure chamber.