Radiant infrared type flame detection apparatus

Abstract

Abstract PURPOSE:To contrive the prevention of occurrence an erroneous alarming and the enhancement of detection capacity, by uniformizing quantity of incident light by adjusting the incident area of infrared rays to a light receiving element regardless of the distance between the light receiving element and an infrared ray generation source. CONSTITUTION:A detector, wherein a condensing lens 6 and an infrared filter 7 are mounted to an opening part and a large number of light receiving elements 8 are mounted therein, is attached to a ceiling in a rotatable manner. Through-holes 12, 13, which are eccentric back and forth with respect to the lens 6 and partially overlapped, are provided to first and second cover plates 11a, 11b provided to the front and back surfaces of the lens 6 by drilling and the incident area of infrared rays to the elements 8 from an infrared ray generation source S is increased and decreased with the increase and decrease of the distance between the generation source S and the elements 8. Next, when the adjacent elements 8 catch infrared rays, a light receiving signal with a level corresponding to the quantity of incident light is outputted from the detector and, when reached a predetermined number of pulses within a set time, an alarm is ordered. By this method, incident quantity is uniformized and reliability can be enhanced.

Inventors

• 👤 Takashi Odajima
• 👤 小田島　隆
• 👤 Takashi Onishi
• 👤 崇 大西
• 👤 Hiroshi Hasegawa
• 👤 博 長谷川
• 👤 Yoshimichi Shoji
• 👤 庄司　好道

Bibliographic Details