| 摘要 |
PROBLEM TO BE SOLVED: To solve problems for example, a conventional flame sensor comprises a contamination degree measurement light emission element and a contamination degree measurement light receiving element, for measuring a contamination degree of a light receiving window on a front part of the light receiving element, but, because a lamp part position being the light emission part of the contamination degree measurement light emission element is a far position from a circuit board, so that, a light emission direction has to be adjusted, and even when adjusting the direction, the light emission direction is not stabilized, and there is risk of variation of a light receiving amount of the contamination degree measurement light receiving element.SOLUTION: A stationary spacer for attaching a contamination degree measurement light emission element to a circuit board is provided, and a lamp part of the contamination degree measurement light emission element is positioned and fixed to the stationary spacer, therefore a light emission direction of the contamination degree measurement light emission element is fixed to a predetermined direction.SELECTED DRAWING: Figure 1 |
