Hochiki Corporation

Takeshi Tanigawa

Yukio Yamauchi

Yuichiro Yamamoto

Yoshinori Kaminaka

Hiroshi Ito

Tadashi Sugiyama

Yoshifusa Saito

Shunichi Shoji

Apparatus for monitoring fire and effecting indication and control operations comprises a matrix monitoring signal line network comprising vertical lines and horizontal lines. A plurality of sensing blocks are connected between vertical lines and horizontal lines of the network. Each of the sensing blocks comprises a sensor connected to a power supply. A monitoring circuit having a switch controlled by the sensor and a diode of forward direction in series with the switch is connected between the respective vertical line and horizontal line of the network. An operating circuit connected in parallel with the monitoring circuit comprises a relay connected in series with a second diode of reverse direction. The horizontal lines and vertical lines of the network are sequentially scanned by a circuit including a counter and demultiplexer. When the scanning detects a short circuit produced by operation of a sensor and respective monitoring circuit, the polarity of the vertical and horizontal lines of the network are reversed and this results in operation of the operating circuit to activate an indicator and any accessory controls such as door closers and the like. After reversal of polarity, the network is again scanned and normal polarity of the network is thereafter restored.

Apparatus for monitoring fire and effecting control operation

A monitoring system having physical condition detectors arranged at places remote from a central receiving device so as to detect changes in the physical condition of a matter to be observed such as temperature, light and smoke. The central receiving device impresses detection mode signals on the output portions of detectors to control the outputs thereof. When said receiving device receives an output fed from said detectors by one of detection mode signals, said receiving device displays a physical condition of matter responding to the detection mode signal, thereby enabling the physical condition of matter to be continuously observed responding to detection mode signals and according to the lapse of time.

Physical condition monitoring system for detection in remote places

Fire observation system comprises a central receiving device and detectors, said central receiving device being provided with a remotely searching means for generating detection mode changing signals to continuously change the quantity of detection from a small value to a large one by means of electrical output units, which are connected to the detectors and can feed an output corresponding to the quantity of detection detected by each of detectors, and each of detectors being provided with an intrinsic signal feeding means for causing each of detectors to receive the detection mode changing signal and feed to the central receiving device the quantity of detection detected by the detector at the place where a fire is developing. Said fire observation system is intended to observe the condition of area surrounding a place where a fire is broken and search the development of fire at the place, after the break of fire is warned by detecting a predetermined reference value of a matter such as smoke, temperature and light.

Fire detection and observation system

Disclosed herein is an improved composite-type heat-system fire sensing device consisting essentially of a differential sensing element and constant-temperature sensing element, capable respectively of actuating a pair of electric contacts. These two type of sensing elements used in customary devices are difficult to assemble and to adjust. There are also serious problems for production and wider utilization of the sensing device. Further, the elements lack practical utilizability as well as reliability. The sensing device of this invention overcomes the abovementioned problems of the customary devices by effecting sensitivity matching of different operation characteristics of the two sensing elements, and makes it possible to optionally and freely adjust the sensitivity of the sensing device as required in accordance with the conditions of the place of installation of the sensing device so as to ensure a higher reliability and wider application of the sensing device.

Composite-type heat-system fire sensing device

Circuit conduction test arrangement for emergency alarm systems having a receiving panel for a group of several sections to be supervised and including common alarm means, and a plurality of relay panels installed in the respective sections; comprising in each relay panel a sensor and an alarm device connected in parallel, said relay panels including a test switch, a reset switch and an impedance network; the receiving panel including means responsive to the variation of the input impedance, having first and second responsive devices connected in a particular manner so as to provide safe operation for the circuit conduction tests. In the test operation, the common alarm means does not operate, and only the alarm device of the relaying panel operates which has its text switch activated.

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Machida, Japan

Takeshi Tanigawa