ULTRASONIC DETECTOR

• Main Author: KAWAGUCHI SHOJIRO
• Format: Patent
• Language: English
• Published: 10.07.1991
• Subjects: ANALOGOUS ARRANGEMENTS USING OTHER WAVES; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION ORRERADIATION OF RADIO WAVES; MEASURING; PHYSICS; RADIO DIRECTION-FINDING; RADIO NAVIGATION; TESTING

PURPOSE:To prevent erroneous detection otherwise caused by water drops by narrowing a detection area so as not to detect water drops when water drops attributed to a falling of rain or the like are detected. CONSTITUTION:When the attaching of water drops is detected with a water drop detecting section 60 mounted on a vehicle near a transmitter/receiver 13, a water drop detection circuit 6 out puts a water drop detection signal to a receiving amplification circuit 4. Then, in a receiving amplification circuit 4, when the water drop detection signal is inputted, a gain is altered to a specified low level. The water drop detecting section 60 is made up of parallel linear electrodes 61 and 62 formed sandwiching a specified gap 64 to such an extent that short-circuiting is caused even by a water drop adhering to an insulating body 63 with a falling of rain, washing of a car or the like. Then, when a water drop adheres to the water drop detecting section 60, a low resistance occurs between the electrodes 61 and 62 to turn ON a transistor and a low or high level is outputted as water drop detection signal at an output end.