PRESSURE REGULATOR FOR FIRE EXTINGUISHING SYSTEM

PURPOSE:To enable the prevention of abnormal boosting on a secondary side to hold a secondary side pressure and prevention of water sprinkling by a malfunction with an increase or decrease of the number of parts without separately disposing a safety valve and pressure regulating valve on a piping. CONSTITUTION:This pressure regulating valve is designed to maintain the fluid pressure on a secondary side at a prescribed value by opening and closing the valve disk of a ball valve body 10 via a valve disk driving section 20 in accordance with control of a pressure switch 50 for detecting the fluid pressure on the secondary side. The pressure regulating valve is so constituted that a replenishing safety valve for holding the secondary side fluid pressure at the time of warning, a limit switch for detecting the operation of the valve disk and a switch turning on cooperatively with a fire detector are mountable thereon.