Abstract: A pressure regulating valve includes a device body and an actuator. The device body includes a valve seat member, a valve, which is capable of closing the first opening of the valve seat member, an urging member, which urges the valve toward the valve seat member, a piston arranged opposite to the valve across the valve seat member, an actuator, which adjusts the position of the piston, and a protrusion provided on at least one of the piston and the valve. When the tip end of the protrusion comes into contact with the piston or the valve, the second opening of the second fluid passage is closed. When the tip end of the protrusion is not in contact with any of the piston and the valve and the second opening is opened, the second fluid passage is in communication with the pressure regulation chamber.

Abstract: A pressure regulating valve includes a device body and an actuator. The device body includes a valve seat member, a valve, which is capable of closing the first opening of the valve seat member, an urging member, which urges the valve toward the valve seat member, a piston arranged opposite to the valve across the valve seat member, an actuator, which adjusts the position of the piston, and a protrusion provided on at least one of the piston and the valve. When the tip end of the protrusion comes into contact with the piston or the valve, the second opening of the second fluid passage is closed. When the tip end of the protrusion is not in contact with any of the piston and the valve and the second opening is opened, the second fluid passage is in communication with the pressure regulation chamber.

Abstract: An evaporative emission control system is provided wherein a differential pressure valve includes a diaphragm that separates a back pressure chamber and a tank chamber from each other, and has a communication hole formed therethrough. The differential pressure valve is placed in an open state in which the diaphragm is spaced apart from a valve seat, or a closed state in which the diaphragm rests on the valve seat. The differential pressure valve further includes a closure member for closing the communication hole when the differential pressure valve is placed in the closed state, and the communication hole communicates with the back pressure chamber and the tank chamber when the differential pressure valve is in the open state.