| 摘要 |
PURPOSE:To simplify the construction of an ultrasonic pulse detector and reduce the number of mutual wirings therein by internally containing a time constant circuit for setting an ultrasonic wave emitting timing in respective ultrasonic wave pulse radars and connecting the radars employing the same ultrasonic pulse wave in parallel. CONSTITUTION:In an ultrasonic pulse detector having a plurality of ultrasonic wave pulse radars 1 each including a transmitter 2 for transmitting ultrasonic pulse and a receiver switch circuit 3 for receiving reflected wave and controlling a relay 19 in the same sound field, a time constant circuit 5 for setting an ultrasonic wave emitting timing is internally contained in each of the pulse radars 1, and the transmitter 2 is so constructed as to transmit an ultrasonic wave pulse when the output signal of the receiver circuit becomes not existed. Thus, it is not necessary to provide a master equipment having a special synchronizing signal generator but necessary to provide only two signal wirings between the pulse radars 1. |
