| 摘要 |
PURPOSE:To position equipment in the center of space suitably and to receive an ultrasonic wave in any direction with constant sensitivity by providing a receiving microphone upside down in the center of a main body bottom part and arranging a conic reflector in front of the microphone. CONSTITUTION:In the center of the bottom part of a cylindrical main body, the receiving microphone is arranged with the down and in front of the microphone, the conic reflector which decreases in sectional area in accord with the approach to the receiving microphone is arranged facing oppositely to the receiving microphone. For example, the receiving microphone 2 is arranged in the bottom part center of the cylindrical main body 1 with the top down to avoid the accumulation of dust and in front of this receiving microphone 2, the truncated conic reflector 3 is arranged closely through a supporting rod 4. For the main body bottom part 1a and microphone-side surfaces 3a of the truncated conic body which form a path for an ultrasonic wave signal, a material having large reflectivity for an acoustic wave is used and to form a smooth surface enough not to cause diffused reflection. Then as the ultrasonic wave signal approaches the receiving microphone 2, the opening area of the path decreases to emphasize roughness and fineness, and to increase the intensity. |
