OBJECT DETECTION DEVICE

To provide an object detection device capable of accurately and stably measuring an object in a vessel, without requiring maintenance of a dust intrusion preventive member.SOLUTION: An object detection device 100 includes: a dust intrusion prevention device 300 which includes an annular main body part installed at an opening 201 formed on a vessel 200 or a conveyance path, an annular cavity formed across the whole circumference inside the main body part, an inclined surface gradually descending toward a central part of the main body part, an annular slit communicating with the cavity from a proper place of the inclined surface, and an open hole communicating with the cavity from an outer peripheral surface of the main body part, and which supplies compressed gas from the open hole through the slit; an outer air take-in member 400 which is attached to the main body part of the dust intrusion prevention device 300, and in which open holes 401 are formed to take-in outer air; a guide pipe 500 mounted to the outer air take-in member 400; and a detection wave transmitting and receiving device 600 installed via the guide pipe 500.SELECTED DRAWING: Figure 1 【課題】粉塵侵入防止用部材のメンテナンスが不要で、容器内の物体を正確に安定して測定できる物体検出装置を提供する。【解決手段】本発明の物体検出装置１００は、容器２００または搬送路に形成された開口２０１に設置される環状の本体部と、本体部の内部に全周にわたり形成される環状の空洞と、本体部の中央部に向かって漸次降下する傾斜面と、傾斜面の適所から前記空洞に通じる環状のスリットと、本体部の外周面から空洞に通じる貫通孔とを有し、貫通孔からスリットを通じて圧縮ガスを供給する粉塵侵入防止装置３００と、粉塵侵入防止装置３００の本体部に取り付けられ、外気を取り入れるための貫通孔４０１が形成された外気取入部材４００と、外気取入部材４００に取り付けられるガイドパイプ５００と、ガイドパイプ５００を介して設置される検出波の送受信装置６００と、を備える。【選択図】図１