| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to securely detect smoke production without any malfunction in noisy electric equipment and know abnormality of the electric equipment before firing by emitting and receiving light by using a burst signal. SOLUTION: A control means 4 outputs a burst code signal as a control signal for a light emitting element 21 to a light projecting means 2, and receives a light reception signal from a light receiving means 3 and compares it with the burst code signal to decide whether or not there is smoke in a detection space 52. The CPU of a microcomputer having a burst code signal, etc., is used as this control means 4. For example, a CPU which is used for other purposes such as remote control over electric equipment and has a function for outputting a desired burst code signal and also compares an inputted signal with its burst signal may be used. In this case, a comparing circuit is only provided additionally unless the CPU has the comparing function. |
