Hochiki Corporation

Hochiki Kabushiki Kaisha

Isao Asano

Satoshi Nakajima

Yoshimi Kawabata

Yoshitaka Egawa

Hiroshi Shima

Sadataka Yuchi

Atsushi Mammoto

Takashi Shimokawa

Hiroshi Nishizaki

Kumiko Ando

An alarm unit of the invention is provided with: a light emitting section; a battery power supply; a voltage booster circuit that boosts a voltage from this battery power supply to thereby generate a boosted voltage; a light emission control section that controls the voltage booster circuit to supply, with the timing at which the boosted voltage is obtained, the boosted voltage to the light emitting section, thereby intermittently driving light emission; a light receiving section that receives light from the light emitting section having been diffused by smoke; a conversion circuit that converts a received light signal from the light receiving section into received light data; a fire hazard detection section that detects a fire hazard based on the received light data from the conversion circuit; an alarm section that outputs an alarm based on a fire hazard detection signal from the fire hazard detection section; a reference voltage circuit that generates a reference voltage for the voltage booster circuit and the conversion circuit; and a clock circuit that outputs a clock signal for operating the voltage booster circuit, the light emission control section, and the conversion circuit. Furthermore, in this alarm unit, a packaged integrated circuit is provided with: a processor circuit that realizes functions of the light emission control section and the fire hazard detection section by executing a program; the voltage booster circuit; the conversion circuit; the reference voltage circuit; the clock circuit; and a control circuit of the respective circuit sections.

Alarm unit

A fire distinguishing device includes: a detection device which detects an outbreak of a fire; a fire presence/absence distinguishing device which distinguishes the presence or absence of the fire; and a cumulative time determining device which determines the cumulative time required for distinguishing the presence or absence of the fire, in the fire presence/absence distinguishing device. The cumulative time determining device distinguishes an environment type of an environment where the detection device is installed, or a phenomenon type of a phenomenon being detected by the detection device, and further determines the cumulative time according to the distinguished environment type or phenomenon type.

Fire distinguishing device

An alarm device includes: a detection device which detects an occurrence of an abnormal condition within a monitoring area; a transmission device which transmits an alarm signal when the detection device detects the abnormal condition; and an output device which, after the transmission device has transmitted the alarm signal, outputs an alarm after a lapse of a predetermined time after the transmission.

Alarm device and alarm system

A D/A converter outputs analog voltage in a range of 0 to 2 V in accordance with a digital value in a range of 0 to 31 outputted from a light emission control unit, and supplies the analog voltage to a voltage/current conversion unit. Driving current outputted from the voltage/current conversion unit is controlled on a 1 mA unit basis in a range of 0 to 31 mA in accordance with the digital value. Driving current outputted from a voltage/current conversion unit is controlled on a 4 mA unit basis in a range of 0 to 124 mA, and driving current outputted from a voltage/current conversion unit is controlled on a 20 mA unit basis in a range of 0 to 620 mA. The voltage/current conversion units are on-off controlled in accordance with range designation signals, respectively. Accordingly, the luminance of the LED can be controlled in a wide range and accurately even in a low luminance level.

Light emission circuit

A driving unit generates a driving current corresponding to a light generation control signal CTL supplied from a light generation controlling unit. The driving current is supplied to an LED. Light emitted from the LED impinges on a light receiving circuit through a space of a monitoring area. The received light level of the light receiving circuit is converted into a received light level signal RLV in an A/D. The received light level signal RLV is supplied to a smoke detecting unit and the light generation controlling unit. The received light level signal RLV is monitored in a short period by the smoke detecting unit. When the received light level signal RLV is equal to or lower than an alarm level, an alarm signal ALM is output. The light generation controlling unit compares the received light level signal RLV with a reference level in a long period. The light generation control signal CTL is increased or decreased so that the level difference between the received light level signal RLV and the reference level is eliminated.

Light obstruction type smoke sensor

A thermal detector in which an element unit has a heat sensor element such as a, thermistor, sealed into the terminal end portion thereof, for electrically detecting temperature change. A detector body integrates by plastic-forming a pair of fitting members for electrically and mechanically coupling to a detector base. A circuit board is mounted on a circuit accommodation portion inside the detector body. A back side cove is provided for closing and sealing the circuit accommodation portion from the reverse side thereof. Airtightness of the circuit accommodation portion is thereby secured and it is simplified to make possible automatization. Positioning projections and respective positioning grooves are provided. By respectively fitting these, positioning is achieved of the circuit board to a molded body, the back side cover to the reverse side of the molded body and the outer cover to the lower side of the molded body. In such a positioned state, the back side cover, the circuit board, the molded body and the outer cover are fixed into one body by screwing of the fitting members. Positioning of a plurality of component parts at the time of assembling is simplified thereby to achieve an improvement in working efficiency and assembling precision.

Thermal detector

A thermal detector comprises: an element unit 11 having a heat sensor element 1 such as a thermistor sealed into the terminal end portion thereof, for electrically detecting temperature change; a detector body integrating by means of plastic-forming a pair of fitting members 12 for electrically and mechanically coupling to a detector base; a circuit board 16 mounted on a circuit accommodation portion 15 inside the detector body; and a back side cover 17 for closing and sealing the circuit accommodation portion 15 from the reverse side thereof. Thereby, airtightness of the circuit accommodation portion is secured and it is simplified to make possible automatization thereof. Also, positioning projections 110, 112, 114 and positioning grooves 111, 113, 115 are provided. By respectively fitting these, positioning of the circuit board 16 to a molded body 14, the back side cover 17 to the reverse side of the molded body 14 and the outer cover 13 to the lower side of the molded body 14 is effected. The back side cover 17, the circuit board 16, the molded body 14 and the outer cover 13 in such positioned state are fixed into one body by means of screwing of the fitting members 12. Thereby positioning of a plurality of component parts at the time of assembling is simplified to achieve an improvement in working efficiency and assembling precision.

Growing community of inventors

Tokyo, Japan

Isao Asano