Pressure regulating valve

A pressure regulating valve, comprising:

• a device body including
• an inflow portion into which fluid flows;
• a valve chamber that is in communication with the inflow portion;
• an outflow portion out of which the fluid flows;
• a pressure regulation chamber that is in communication with the outflow portion;
• a valve seat member, which separates the valve chamber and the pressure regulation chamber from each other;
• a valve located in the valve chamber, wherein the valve is capable of closing a first opening of the valve seat member;
• an urging member, which applies an urging force to the valve in a direction toward the valve seat member;
• a piston arranged opposite to the valve across the valve seat member;
• an actuator, which adjusts a position of the piston in accordance with a power supply state;
• a first fluid passage, which draws the fluid in the valve chamber into the pressure regulation chamber, wherein the first fluid passage is connected with the pressure regulation chamber via the first opening in a state where the valve is separated from the valve seat member;
• a second fluid passage provided in the valve, wherein the second fluid passage includes
• a second opening, has a cross-sectional area that is different from
• a cross-sectional area of the first fluid passage and draws the fluid in the valve chamber into the pressure regulation chamber;
• and
• a protrusion, which is provided on at least one of the piston and the valve, wherein in a case where the protrusion is provided on the piston, the protrusion protrudes toward the valve through the first opening, and when a tip end of the protrusion comes into contact with the valve, the second opening of the second fluid passage is closed, in a case where the protrusion is provided on the valve, the protrusion protrudes toward the piston through the first opening, and when the tip end of the protrusion comes into contact with the piston, the second opening of the second fluid passage is closed, in a case where the protrusion is provided on each of the piston and the valve, the protrusion on the piston protrudes toward the valve through the first opening, the protrusion on the valve protrudes toward the piston through the first opening, and when the tip end of the protrusion on the valve comes into contact with the tip end of the protrusion on the piston, the second opening of the second fluid passage is closed, and when the tip end of the protrusion is out of 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, wherein the urging member is a first urging member, wherein at least a part of the piston is formed from a magnetic material, the actuator includes an electromagnetic coil arranged radially outward of the piston, a second urging member arranged in an accommodation chamber opposite to the valve chamber across the pressure regulation chamber, wherein the second urging member applies an urging force to a wall of the pressure regulation chamber and the second urging member applies an urging force to the piston in a direction toward the valve, and wherein the urging force by the second urging member is less than the urging force by the first urging member.