公开(公告)号：EP3435068A1

公开(公告)日：2019-01-30

申请号：EP17769886.7

申请日：2017-03-06

申请人： Yanmar Co., Ltd. ,  Fuji Electric Co., Ltd.

发明人： FUKUI Yoshinori ,  KOBAYASHI Ryota ,  YOKOYAMA Tetsuya ,  INOUE Tsuyoshi ,  ODA Yusuke ,  OKADA Michiyasu ,  AKAO Kozo ,  HIGASHI Ryouichi

IPC分类号： G01N21/03 ,  G01N21/15 ,  G01N21/85 ,  G01N21/3504

摘要： A gas concentration measuring device 1 related to the present invention includes a light emitter 3 and a light receiver 4 which are disposed so as to be opposed to each other with a hollow tube-like measurement pipe 2 interposed therebetween and the device 1 is configured to measure concentration of target gas passing through the measurement pipe 2 using light applied from the light emitter 3, transmitted through an inside of the measurement pipe 2, and received by the light receiver 4. Purge gas guide pipes 11, 13 through which purge gas is introduced into optical systems of the light emitter 3 and the light receiver 4 are connected to a side wall of the measurement pipe 2. The measurement pipe 2 includes a gas entrance portion 21 having a tapered shape widening from a gas supply port toward a downstream side.