JPS6034298B2 - Ultrasonic transducer transmitter/receiver switching circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmitting/receiving switching circuit for a transducer that converts electrical signals into ultrasonic waves and converts ultrasonic signals into electrical signals in an underwater telephone.

Traditional battery operated underwater telephones It was about 2.7 kHz in the 10 hW band.

However, in order to transmit and receive broadband high power such as several watts or several 1 OW and 9.7 kHz in a band, it is not possible to cause the transducer to resonate in a single manner, and the transmission voltage must be set to a high voltage. However, when outputting high voltage with a device that operates on a low-voltage power source such as a battery, loop oscillation is likely to occur, making it difficult to make it compact and operate stably. Furthermore, the configuration of a wideband, high-efficiency transducer has become complicated. In order to eliminate these drawbacks, the present invention requires only a pair of electric wires connecting the transceiver and the transducer, which enables high-output transmission with low-voltage transmission signals, and efficiently transmits and receives the received voltage during reception. The purpose is to provide a transmission/reception switching circuit for an ultrasonic transducer that can be supplied to an ultrasonic transducer.

A detailed explanation will be given below with reference to the drawings. FIG. 1 is a connection diagram showing one embodiment of the present invention. 1 and 2 are input terminals, LI and L2 are primary and secondary coils wound on the same coil, C
RI~CR4 is a diode, CI is a capacitor, EI~
E9 is a vibrator.

FIG. 2 is a functional diagram when the device shown in FIG. 1 operates as a transmitter.

FIG. 3 is a functional diagram when the device shown in FIG. 1 operates as a receiver. First, the operation as a transmitter will be explained.

Transmission and reception power from a transceiver (not shown) is supplied to input/output terminals 1 and 2 in FIG. 1 through two lines. Diode CR1,C
Since R2 is a diode with a forward cutoff voltage sufficiently lower than the transmission signal supplied to the input/output terminals 1 and 2, it is in a short-circuited state, and the transmission signal is applied to both ends of the coil LI. Since the coils LI and L2 are wound on the same core, they act as a single-winding flyback transformer, and the oscillator E
A transmission signal boosted to a high voltage is supplied to I to E9.
The oscillators EI to E9 are oscillators with slightly different resonance frequencies, and are selected so that the combined frequency characteristics cover the required range. The number of vibrators is not limited to nine, and can be increased or decreased as necessary. The forward cutoff voltage of diodes CR3 and CR4 is sufficiently lower than the voltage applied to the oscillators EI to E9, so they are short-circuited, and the capacitor CI is connected to the oscillator E.
Enter in parallel with 1 to E9.

It is not necessarily easy to select each vibrator so that the combined frequency of the vibrators EI to E9 is even, and valleys are likely to occur. The capacitor CI is combined with the capacitance of the vibrators EI to E9 to resonate at the frequency of the trough with the capacitance of the single-winding linear transformer composed of the primary coil LI and the secondary coil L2, thereby improving the frequency characteristics. Therefore, if necessary, the oscillator E
It may be inserted in series with I to E9 or elevated. If omitted, diodes CR3 and CR4 are unnecessary. FIG. 2 shows the function of FIG. 1 when it operates as a transmitter. As shown in the above description of operation, CRI to CR4 are short-circuited, so one end of each of C1, L1, and EI to E9 is connected to two ends of the input/output terminals.

Next, the operation as a receiver will be explained.

Since the received voltage appearing on the oscillators EI to E9 is weak, it is not possible to conduct the diodes CRI to CR4.
Diodes CRI-CR4, capacitor CI and primary coil LI are functionally excluded from the circuit (FIG. 3). Therefore, the received voltage is output to input/output terminal 1 and terminal 2 through secondary coil L2. If you want to widen the band with one oscillator, you can insert a damping resistor in parallel with the oscillator, but this will result in poor power efficiency. If a wide band is not required, there is no need for a damping resistor, just make the circuit resonate at the frequency used.
As explained above, during transmission, the transmission voltage between input/output terminal 1 and terminal 2 can be boosted to supply high-voltage transmission signals to the transducers 1 to E9, and during reception, the received voltage can be efficiently used for transmission. It can be output to the transmitter/receiver using two wires from the common input/output terminals 1 and 2. Therefore, wide-band, high-output transmission and reception can be easily and stably performed using a small-sized, low-voltage power transmitter/receiver. The present invention is applicable not only to underwater telephones but also to all ultrasonic transducers.

[Brief explanation of drawings]

FIG. 1 is a connection diagram for implementing the present invention. FIG. 2 is a functional diagram as a transmitter, and FIG. 3 is a functional diagram as a receiver. 1, 2...Input/output terminal, L1...
...Primary coil, L2...Secondary coil, CRI
~CR4...Diode, CI...Capacitor, EI~E9...Resonator. Case 1 figure belt 2 figure boar 3 figure

Claims (1)

[Claims] 1. A single-winding transformer consisting of a primary coil L_1 and a secondary coil L_2, diodes CR_1 and CR_2 connected in antiparallel to each other connected in series with the transformer, and a capacitor C_1 connected in parallel with the transformer. A series circuit of diodes CR_3 and CR_4 connected in antiparallel to each other, a plurality of vibrators connected in parallel to a connection point between the secondary coil L_2 and the capacitor C_1, and the other ends of the diodes CR_1 and CR_2. Ultrasonic wave transmission and reception, characterized in that a transmission signal is applied to a connection point between the primary coil L_1 and the secondary coil L_2 of the transformer and a connection point between the diodes CR_1, CR_2 and the vibrator. transmitter/receiver switching circuit.