SU1465130A1 - Arrangement for device for power supply unit of ultrasonic transducer - Google Patents

Abstract

The invention is intended for use in the field of ultrasound technology and technology. The device contains an ultrasonic generator 1 connected to the inputs of the power amplifier 2 and the clock pulse generator 3, the output of which is connected to the control input of the key 4 and through the inverter 7 to the key 6. The output of the amplifier is connected via the key 4 to the input of the ultrasonic converter and to the second key 6. The output of the second key is connected via an amplitude detector 8 to the reverse unit and to the control input of an integrator with a variable time constant, the output of the reverse unit is connected via an integrator to the control input. 2 Il. ip cl

Description

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The invention relates to ultrasound technology and technology, to automatic frequency control systems.

The aim of the invention is to improve the accuracy of auto-tuning.

FIG. 1 shows a block diagram of the device; in fig. 2 - voltage plots at the output of some units of the device.

The device works as follows.

The harmonic signal from ultrasonic generator 1 is fed to power amplifier 2 and clock pulse generator 3, which generates pulses controlling the operation of switch 4, which is located at the input of ultrasonic converter 5 and switch 6, connected to generator 3 via inverter 7. The control input of the first key is shown in FIG. 2a, and the voltage plot at the input of the ultrasound transducer is shown in FIG. 26. The clock pulse generator via key 4 pauses the operation of the ultrasonic transducer. During transducer operation, its operating frequency is set by ultrasonic generator 1, and during pause, the frequency at the input of the ultrasonic transducer is equal to the natural frequency of the transducer, and the signal amplitude is determined by the proximity of the operating frequency of the transducer to its resonant frequency (Fig. 26). The maximum signal corresponds to the operating mode of the ultrasonic transducer at the resonant frequency. The second key is unlocked only during pauses. The signal from it (Fig. 2c) goes to the detector 8, which converts the harmonic pulse during the pause to a constant voltage between the pauses (Fig. 2d). The signal from the detector goes to the reverse 9 unit and to the integrator control input with a variable time constant 10, from the integrator output is a signal whose rise rate is inversely proportional to the difference between the operating frequency of the generator 1 and the resonant frequency of the converter 5 (Fig. 2e). The use of an integrator with a variable time constant ensures a smooth transition of the converter 5 to the resonant mode. The accuracy of the auto-tuning is 0.5%.

Claims (1)

Invention Formula A power source auto-tuning device for an ultrasonic transducer containing a clock pulse connected to the output of an ultrasonic generator, connected via a key to a power amplifier and through an inverting cell to a control input of a second key, in order to increase the accuracy of auto-tuning, the output of a power amplifier through the first key is connected to the input of the ultrasonic transducer connected to the input of the second key, the output of which is connected to the input of the reverse unit and a control input of said variable integrator time constant, the output unit via the reverse integrator is connected to the ultrasonic generator input. cpusZ