Patent attributes
Disclosed herein is a passage detection apparatus capable of detecting a passage of an object in a specific space. The passage detection apparatus includes a transmitting device, a receiving device, and a shielding member. The transmitting device is provided with a vibration generating source. The receiving device is arranged at the position corresponding to the transmitting device across the specific space. The shielding member has a through-hole, and is arranged so as to be interposed between the transmitting device and the receiving device. The vibration transmitted from the transmitting device reaches the receiving device via the through-hole and a passage route of the object. On the other hand, the reception of the vibration, reflected in the specific space, by the receiving device is suppressed by the shielding member.
