Patent ID: 8641176

Claim:
A pressure-regulating valve for opening and closing a valve body provided to a communication flow passage via which a primary chamber and a secondary chamber communicate inside a valve housing, with the aid of a pressure-receiving membrane that constitutes one surface of the secondary chamber, for regulating the pressure of a liquid fed to the primary chamber via an inflow port, and for feeding the liquid from the secondary chamber via an outflow port, wherein a cover for allowing action of the pressure-receiving membrane covers an entirety of the pressure-receiving membrane from one side of the pressure-receiving membrane, the cover is formed in the shape of a cap using a covering wall portion that faces the pressure-receiving membrane, and a peripheral wall portion that extends to the covering wall portion, the cover is detachably attached to the valve housing, the cover has a communication hole for communicating to atmosphere, the communication hole being formed in the peripheral wall portion, and the cover has light-blocking properties.