Abstract: A a fire protection system controls terminal units, or devices which are connected to the terminal units, according to a predetermined control command through control circulars provided at the terminal units. The terminal units have timer circuits which work a predetermined timing operation in response to reception of the control command, whereby the terminal units or the devices to be controlled are controlled during the time interval determined by the timing operation.

Abstract: A signal transmission circuit provided with a control panel or a terminal device of a fire/security protection system is arranged so as to transmit a signal for the control panel or terminal device to a signal line. The signal transmission circuit includes: a signal transmission which is enabled when transmitting a signal under the control of a signal processing portion; a signal detector for detecting the signal transmitted from the signal transmitter to the signal line; a timer which is set when the signal is transmitted and is reset by the detection output from the signal detector, and a signal transmission controller for turning off the signal transmitter when the time count output of the timer exists during a predetermined time interval.

Abstract: In a fire alarm system wherein a receiver polls terminal devices having CPU's, such as fire detectors, fire sensors and repeaters, and the receiver reads monitoring information called from the terminal device or transmits control information thereto; a fire alarm system constructed so that each of said terminal devices having a CPU brings said CPU included therein into a standby status when a polling address of said receiver and an intrinsic address of said terminal device are different.

Abstract: In an ionization-type smoke detector wherein inner, intermediate and outer electrodes are supported on an insulating base, an inner ionization chamber and an outer ionization chamber being constituted by the inner and intermediate electrodes, and the intermediate and outer electrodes respectively, and a radioactive source provided to irradiate both of the ionization chambers, a detector is disclosed wherein the insulating base is formed with a through-hole to connect its upper and lower parts, the inner electrode being passed through the hole to be supported inside the insulating base at its upper portion, and the outer electrode is supported on the outside of the insulating base at its upper parts with an intervening substance being interposed therebetween, whereby the mutual creepage distances between the respective electrodes are elongated.

Abstract: An apparatus for generating high expansion foam. The disclosed apparatus includes an elongated housing having an inlet and an outlet and a perforated member extending across its free passage area. A fan is positioned in the housing and drivingly rotated by impulse nozzles supplied with pressurized liquid foam solution. The nozzles are arranged tangentially to the rotational axis of the fan, in a plane normal to the axis. A deflector is positioned around the nozzles so as to direct jet spray of the liquid foam solution partially toward the central portion of the perforated member and partly toward the outer edge portion of the perforated member to provide a relatively uniform wetting of the perforated means. The deflector further provides means for permitting all the nozzles to be directed tangentially to the rotational axis in design and to be mounted at the greatest possible distance from the shaft to provide the largest moment arm in order to increase percentage of the power available in the water supply.