Abstract: Provided is an explosion-proof structure of a power source part, an explosion-proof type battery unit and an explosion-proof type gas alarm, in which the degree of temperature rise upon short circuit of a secondary battery is reduced and explosion-proof performance with high reliability is achieved. The explosion-proof structure of a power source in an explosion-proof type apparatus employing a secondary battery as a power source for driving is fabricated by arranging a heat-radiating member composed of a metal at an outer peripheral surface of the secondary battery in a state that at least a part thereof comes into close contact with the surface. The explosion-proof type battery unit is composed of a cylindrical secondary battery and a heat-radiating member composed of a metal provided at an outer peripheral surface of the secondary battery in a state that at least a part thereof comes into close contact with the surface.

Abstract: Disclosed is a portable gas alarm device easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas alarm device comprises a gas alarm device body having a casing flat in whole and a fitting member provided on the casing to fit it to the human body. The gas alarm device body has a control circuit board extending to the direction of the flat plane of the casing, a display mechanism is arranged in a central area on the front surface side of the control circuit board, a gas sensor and an alarm buzzer are arranged on the right and left sides of the display mechanism, and a battery fitting chamber is provided on the back surface side of the circuit board. A vibration generator for alarm may be provided in the gas alarm device body. The fitting member may be one suitable for use in fitting the gas alarm device body to a person's wrist or a person's wear.

Abstract: A portable gas detector comprises a casing proper 1 adapted to be attached to the human body. The casing proper 1 has multiple openings to accommodate gas sensors 5 on one side and charging terminals 38 and a communication window 14 on the other. Calibration of the gas sensors and securing of power supply are easy to achieve.

Abstract: Disclosed is a portable gas alarm device easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas alarm device comprises a gas alarm device body having a casing flat in whole and a fitting member provided on the casing to fit it to the human body. The gas alarm device body has a control circuit board extending to the direction of the flat plane of the casing, a display mechanism is arranged in a central area on the front surface side of the control circuit board, a gas sensor and an alarm buzzer are arranged on the right and left sides of the display mechanism, and a battery fitting chamber is provided on the back surface side of the circuit board. A vibration generator for alarm may be provided in the gas alarm device body. The fitting member may be one suitable for use in fitting the gas alarm device body to a person's wrist or a person's wear.