| 摘要 |
PURPOSE:To attain to miniaturize the simplify a sensor, by providing a Fresnel lens condensing heat rays to the heat ray element of a printed circuit board block mounted to the front surface of a body. CONSTITUTION:A sensor is constituted of a base 3, a body 10 and a cover 5. The base 3 consists of a second base 31 having a printed circuit board block 9 received therein and a first base 32 mounted to the wall surface of a structure. A detection circuit detecting a human body is further mounted in the base 3 and the printed circuit board block 9 received in the base 3 is engaged with the inside surface of the opening part of the second base 31 in a state received in the second base 31 and fixed to the body 10. The part mounting a Flesnel lens 2 condensing heat rays to a heat ray element 1 is opened to the front surface of the body 10 and the upper and lower edges of the opening provided to the front surface are protruded in a semicircular shape to provide a projection 11. The cover 5 is mounted to the opening part of the second base 31. By this constitution, because it is unnecessary to use a parabolic mirror in the sensor, the sensor can be miniaturized and the number of assembling processes can be reduced. |
