| 摘要 |
PURPOSE:To obtain a car periphery searching device which can precisely prevent the car from clashing without the influence of a car speed by comparing the distance with a distance to be measured with an ultrasonic wave and changing a prescribed distance to generate alarms in accordance with a car speed. CONSTITUTION:A counter 16 in an alarm device 14' counts up car speed from a car speed sensor 15 and a prescribed distance corresponding to the car speed is latched by a latch circuit 18 and compared with a distance measured by an ultrasonic wave through an arithmetic processing unit 19 in a digital comparator 20. When the measured distance is shorter than the prescribed distance, an alarm is generated through an alarm circuit 21, operating a car periphery searching device which can precisely prevent the car from clashing without the influence of car speed. |
