JP2008219420A - Ultrasonic oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic oscillator for stably obtaining an effective ultrasonic output. <P>SOLUTION: A switching high frequency voltage at secondary side of an output transformer being the voltage of the switching high frequency power at secondary side of output transformer, which is an ultrasonic wave output and is corrected with a power factor, and a switching high frequency voltage at secondary side of an output transformer being a current are respectively converted into an output voltage value detection voltage and an output current value detection voltage. An output power value detection voltage is calculated based on the converted output voltage value detection voltage and output current value detection voltage. Frequencies are swept by a prescribed frequency width at prescribed time interval based on an initial setting oscillation frequency. The frequency having the highest output power value detection voltage for each frequency in sweeping is set as the oscillation frequency. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic oscillator. More specifically, the present invention is suitable for use in applying high-frequency power to an ultrasonic transducer used in various ultrasonic apparatuses such as an ultrasonic cleaning apparatus and an ultrasonic measurement apparatus. In particular, the present invention relates to an ultrasonic oscillator that can track, as an oscillation frequency, a frequency at which the ultrasonic output of various ultrasonic apparatuses using an ultrasonic transducer is maximized.

  Conventionally, in various ultrasonic apparatuses such as an ultrasonic cleaning apparatus and an ultrasonic measurement apparatus using an ultrasonic vibrator, the resonance frequency is influenced by the influence of various conditions such as an ultrasonic processing target or an ultrasonic processing environment. As a result, there is a difference between the resonance frequency and the oscillation frequency of the ultrasonic oscillator that applies high-frequency power to the ultrasonic transducer, and the two deviate from each other, reducing the ultrasonic output in various ultrasonic devices. It was known that.

Specifically, for example, an ultrasonic cleaning apparatus as shown in FIG. 1 is known as an ultrasonic cleaning apparatus using an ultrasonic transducer.

  The ultrasonic cleaning apparatus 100 includes a cleaning tub 104 in which a cleaning liquid 102 is stored, and an ultrasonic oscillator 108 that is attached to the bottom 104 a of the cleaning tub 104 and is connected to an AC power source 106 and is applied with high-frequency power. And a sonic transducer 110.

  Reference numeral 200 denotes an object to be cleaned by the ultrasonic cleaning apparatus 100, and examples of such an object include electronic devices such as a semiconductor wafer substrate and a glass substrate for a liquid crystal display (LCD).

  In the above configuration, according to the ultrasonic cleaning apparatus 100, when high frequency power is applied from the ultrasonic oscillator 108 connected to the AC power source 106 to the ultrasonic vibrator 110, the cleaning basket 104 is transferred from the ultrasonic vibrator 110. The ultrasonic wave is propagated to the cleaning liquid 102 stored in this, and thereby the object 200 to be cleaned can be cleaned.

  However, in general, in such an ultrasonic cleaning apparatus 100, the object to be cleaned 200 is cleaned as described above. However, the shape, quantity, or material of the object to be cleaned 200, the type of the cleaning liquid 102 (liquid type) ), The resonance frequency changes depending on the depth (liquid depth) or temperature (liquid temperature) when stored in the cleaning tub 104.

  Along with the change in the resonance frequency, a difference occurs between the resonance frequency and the oscillation frequency of the ultrasonic oscillator 108, and the both are shifted, resulting in a phenomenon that the ultrasonic output of the ultrasonic cleaning apparatus 100 is reduced. It was supposed to be.

For this reason, as a technique for solving the above-described phenomenon, the resonance frequency and the oscillation frequency of the ultrasonic oscillator 108 are tracked by tracking the resonance frequency using PLL (Phase Locked Loop) control. There has been proposed a method for eliminating the deviation.

However, since the resonance frequency tracking using PLL control is the tracking of the resonance frequency by checking only the phase, if the resonance frequency shifts to a resonance frequency different from the initial setting, the resonance frequency is synchronized with the resonance frequency. There is a possibility that the ultrasonic output due to the oscillated frequency may be lowered or exceeded the set value, and a stable ultrasonic output cannot be obtained.

The prior art that the applicant of the present application knows at the time of filing a patent is as described above and is not an invention related to a known literature, so there is no prior art information to be described.

The present invention has been made in view of the various problems of the conventional techniques as described above, and an object of the present invention is to stably obtain an effective ultrasonic output. An ultrasonic oscillator is to be provided.

  In order to achieve the above object, the ultrasonic oscillator according to the present invention sweeps the frequency of the ultrasonic wave to be irradiated at an arbitrary frequency width at an arbitrary time, and at that time, outputs an ultrasonic output at each frequency being swept. In comparison, the oscillation frequency is set.

  Therefore, according to the ultrasonic oscillator according to the present invention, when the frequency of the ultrasonic wave to be irradiated is swept at an arbitrary frequency width at arbitrary time intervals, the ultrasonic output at each frequency during the sweep is compared, The maximum output frequency can be set as the oscillation frequency for driving.

  For this reason, when cleaning is performed with an ultrasonic cleaning apparatus using an ultrasonic transducer, if the ultrasonic transducer is driven by the ultrasonic oscillator according to the present invention to perform cleaning, the ultrasonic output is always the maximum. It becomes possible to perform cleaning by setting a certain frequency as an oscillation frequency, and a high cleaning ability can be stably obtained.

That is, the invention described in claim 1 of the present invention is an ultrasonic oscillator that applies high frequency power to both poles of an ultrasonic transducer, and DC power is alternately switched between a high side and a low side at a set oscillation frequency. A switching output circuit for generating switching high-frequency power, an output transformer for boosting or stepping down the voltage of the switching high-frequency power generated by the switching output circuit and outputting the output side switching high-frequency power, and the output transformer Output transformer secondary side switching high frequency voltage which is a voltage part of the output transformer secondary side switching high frequency power output from the output transformer secondary side switching high frequency current which is a current part of the output transformer secondary side switching high frequency power Applying to an ultrasonic transducer without phase difference A power factor correction circuit for correcting the power factor, and an output transformer secondary side switching high frequency voltage which is a voltage portion of the output transformer secondary side switching high frequency power outputted from the output transformer to detect an output voltage value detection voltage. Voltage value detection circuit for conversion, and current value for detecting output transformer secondary switching high-frequency current, which is a current portion of output transformer secondary switching high-frequency power output from the output transformer, and converting it to output current value detection voltage A detection circuit; and a multiplier for calculating an output power value detection voltage by multiplying the output voltage value detection voltage converted by the voltage value detection circuit by the output current value detection voltage converted by the current value detection circuit; Control is performed so that the set oscillation frequency is swept at a predetermined time interval and a predetermined frequency width, and the calculated frequency is calculated by the multiplier. Output power detection voltage at each oscillation frequency is obtained so as to have an oscillation frequency setting means for setting the oscillation frequency of the frequency at which the maximum by arguments.

  According to the second aspect of the present invention, in the ultrasonic oscillator that applies high-frequency power to both poles of the ultrasonic transducer, the DC power is alternately switched between the high side and the low side at a set oscillation frequency. A switching output circuit for generating switching high-frequency power, a power factor correction circuit for correcting power factor of the switching high-frequency power generated by the switching output circuit, and a switching high-frequency corrected by the power factor correction circuit In order to apply power to the ultrasonic transducer, an output transformer that steps up or down and outputs the output transformer secondary side switching high frequency power, and a voltage portion of the output transformer secondary side switching high frequency power output from the output transformer. Output voltage value detection by detecting a secondary high-frequency switching voltage of an output transformer A voltage value detection circuit for converting to a voltage, and an output transformer secondary-side switching high-frequency current, which is a current portion of the output-transformer secondary-side switching high-frequency power output from the output transformer, and converting it to an output current value detection voltage A current value detection circuit; and a multiplier for calculating an output power value detection voltage by multiplying the output voltage value detection voltage converted by the voltage value detection circuit by the output current value detection voltage converted by the current value detection circuit When the set oscillation frequency is controlled to be swept at a predetermined time interval and a predetermined frequency width, and the output power value detection voltage at each oscillation frequency calculated by the multiplier is maximized And an oscillation frequency setting means for setting the frequency as an oscillation frequency.

  According to a third aspect of the present invention, in the ultrasonic oscillator that applies high frequency power to both poles of the ultrasonic transducer, DC power is switched alternately between the high side and the low side at a set oscillation frequency. A switching output circuit for generating switching high-frequency power, an output transformer for boosting or stepping down the voltage of the switching high-frequency power generated by the switching output circuit and outputting the output side switching high-frequency power, and the output transformer Output transformer secondary side switching high frequency voltage which is a voltage part of the output transformer secondary side switching high frequency power output from the output transformer secondary side switching high frequency current which is a current part of the output transformer secondary side switching high frequency power Applying to an ultrasonic transducer without phase difference A power factor correction circuit that performs power factor correction on the power source, and a bridge output power that determines the vibration speed of the ultrasonic transducer that vibrates by applying the output transformer secondary side switching high frequency power corrected by the power factor by the power factor correction circuit. And a voltage value detection circuit that detects a bridge output voltage that is a voltage portion of the bridge output power detected by the bridge output power detection resistor and converts it to a bridge output voltage value detection voltage. A current value detection circuit that detects a bridge output current that is a current portion of the bridge output power detected by the bridge output power detection resistor and converts the current to a bridge output current value detection voltage, and the voltage value detection circuit converts the current value detection circuit. Bridge output voltage value detection voltage and the bridge output current value detection voltage converted by the current value detection circuit A multiplier that multiplies and calculates a bridge output power value calculation voltage, and controls to sweep the set oscillation frequency at a predetermined time interval and a predetermined frequency width, and by the sweep calculated by the multiplier And oscillation frequency setting means for setting the frequency at which the bridge output power value calculation voltage at each oscillation frequency is maximum as the oscillation frequency.

  According to a fourth aspect of the present invention, in an ultrasonic oscillator that applies high-frequency power to both poles of an ultrasonic transducer, DC power is switched alternately between a high side and a low side at a set oscillation frequency. A switching output circuit for generating switching high-frequency power, a power factor correction circuit for correcting power factor of the switching high-frequency power generated by the switching output circuit, and a switching high-frequency corrected by the power factor correction circuit Applying the output transformer secondary side switching high frequency power output from the output transformer and the output transformer that outputs the output transformer secondary side switching high frequency power by stepping up or down to apply power to the ultrasonic transducer The vibration speed of the ultrasonic transducer vibrating by the A bridge output power detection resistor, a voltage value detection circuit that detects a bridge output voltage that is a voltage portion of the bridge output power detected by the bridge output power detection resistor, and converts the detected voltage to a bridge output voltage value detection voltage; A current value detection circuit that detects a bridge output current, which is a current portion of the bridge output power detected by the bridge output power detection resistor, and converts it into a bridge output current value detection voltage; and the voltage value detection circuit A multiplier that multiplies the bridge output voltage value detection voltage by the bridge output current value detection voltage converted by the current value detection circuit to calculate the bridge output power value calculation voltage, and sets the oscillation frequency at a predetermined time interval. In addition, control is performed so as to sweep at a predetermined frequency width, and each oscillation frequency by the sweep calculated by the multiplier Bridge output power value calculating voltage definitive is that so as to have an oscillation frequency setting means for setting a frequency as the oscillation frequency when the maximum.

  According to a fifth aspect of the present invention, in the invention according to any one of the first, second, third, and fourth aspects of the present invention, the power factor correction circuit includes the ultrasonic vibration. It is designed to be connected in parallel to the child.

  According to a sixth aspect of the present invention, in the invention according to any one of the first, second, third, and fourth aspects of the present invention, the power factor correction circuit includes the ultrasonic vibration. It is designed to be connected in series to the child.

  The invention according to claim 7 of the present invention is the invention according to any one of claims 1, 2, 3, 4, 5 or 6 of the present invention, wherein the ultrasonic transducer is It is a piezoelectric ultrasonic transducer, and the power factor correction circuit is an inductor.

  Further, the invention according to claim 8 of the present invention is the invention according to any one of claims 1, 2, 3, 4, 5 or 6 of the present invention. 7. The ultrasonic oscillator according to any one of 4, 4, 5 and 6, wherein the ultrasonic vibrator is a magnetostrictive ultrasonic vibrator, and the power factor correction circuit is a capacitor. is there.

  Since the present invention is configured as described above, there is an excellent effect that an ultrasonic oscillator capable of stably obtaining an effective ultrasonic output can be provided.

  Hereinafter, an example of an embodiment of an ultrasonic oscillator according to the present invention will be described in detail with reference to the accompanying drawings.

  In the following description, components that are the same as or correspond to those described previously are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

First, the ultrasonic oscillator according to the first embodiment of the present invention will be described with reference to FIGS.

  The ultrasonic oscillator according to the first embodiment of the present invention shows an example in which high-frequency power is applied to the ultrasonic vibrator 110 mounted on the bottom 104a of the cleaning bowl 104.

  Here, FIG. 2 is a block diagram for explaining the configuration of the ultrasonic oscillator according to the first embodiment of the present invention, and FIG. 3 shows a switching circuit in the ultrasonic oscillator shown in FIG. The schematic circuit explanatory drawing which shows the principal part of the electric power transmission path | route leading to is shown.

  The ultrasonic oscillator 10 according to the first embodiment of the present invention is an embodiment in which the output transformer secondary side switching high frequency power L is monitored and the resonance frequency is tracked. A circuit configuration in which the power factor correction circuit 18 is arranged is shown.

  That is, the ultrasonic oscillator 10 is an ultrasonic oscillator for applying high-frequency power to both poles of the ultrasonic vibrator 110 that is a load, and is connected to the AC power source 106.

  The ultrasonic oscillator 10 rectifies the AC power I applied from the AC power source 106 and converts it into DC power J, and the oscillation in which the DC power J is set by a microcomputer 26 (described later). Switching output circuit 14 for obtaining switching high-frequency power K by alternately switching between a high side (Hi-side) and a low side (Lo-side) at a frequency (hereinafter referred to as “set oscillation frequency” as appropriate) As shown in FIG. 3, the switching output circuit 14 includes high-side FETs (Field Effect Transistors) 141 a and 141 b and low-side FETs 142 a and 142 b), and a switching high frequency. Output transformer 2 by stepping up or down the voltage of power K The output transformer 16 for making the secondary side switching high frequency power L and the output transformer secondary side which is the voltage part of the output transformer secondary side switching high frequency power L by performing power factor correction of the output transformer secondary side switching high frequency power L In order to eliminate the phase difference between the switching high-frequency voltage A and the output transformer secondary-side switching high-frequency current B, which is the current portion of the output transformer secondary-side switching high-frequency power L, to obtain the ultrasonic output M applied to the ultrasonic transducer 110. Power factor correction circuit 18 (in addition, as the power factor correction circuit 18, for example, when the ultrasonic transducer 110 is a piezoelectric ultrasonic transducer, an inductor is used, and the ultrasonic transducer 110 is a magnetostrictive ultrasonic vibration. In the case of the child, it is preferable to use a capacitor.) Voltage value detection circuit 20 that detects transformer secondary side switching high frequency voltage A and converts it to output voltage value detection voltage C, and output transformer secondary side switching high frequency current that is a current portion of output transformer secondary side switching high frequency power L A current value detection circuit 22 that detects B and converts it into an output current value detection voltage D, and outputs an output power value calculation voltage by inputting and multiplying the output voltage value detection voltage C and the output current value detection voltage D A multiplier 24 for calculating E and an oscillation frequency set in advance as an initial setting (hereinafter referred to as “initial setting oscillation frequency” as appropriate. The initial setting oscillation frequency is set as appropriate). A predetermined frequency width (the predetermined frequency width can be arbitrarily set) is set to a predetermined time interval (the predetermined time interval can be arbitrarily set). ) And the output power value calculation voltage E at each oscillation frequency when the sweep operation is performed in a single line, and the oscillation when the output power value calculation voltage E is the highest among the stored output power value calculation voltages E The microcomputer 26 is an oscillation frequency setting means for setting the frequency as the set oscillation frequency, and obtaining and outputting a digital signal indicating the frequency of the set oscillation frequency as the oscillation frequency setting 0/1 signal F. A DDS (Direct Digital Synthesizer) 28 that receives the oscillation frequency setting 0/1 signal F and converts it to the oscillation frequency setting signal G, and amplifies and amplifies the oscillation frequency setting signal G output from the DDS 28 Oscillation frequency setting signal G is output to switching output circuit 1 And a drive circuit 30 that converts it into an FET gate input signal H to be alternately input to the gate terminals of the high-side FETs 141a and 141b and the gate terminals of the low-side FETs 142a and 142b and outputs the FET gate input signal H to the switching output circuit 16. Configured.

  In the ultrasonic oscillator 10, an oscillation frequency processing means is constructed by the microcomputer 26, the DDS 28 and the drive circuit 30.

Here, the microcomputer 26 will be described in more detail. A frequency for sweeping a predetermined frequency width at a predetermined time interval is formed by a program based on the oscillation frequency of the ultrasonic wave irradiated from the ultrasonic transducer 110. Can output an oscillation frequency setting signal that can be output, and compares the output power value calculation value E at each frequency during the sweep, and sets the frequency when the output power value calculation value E is maximum after the sweep A digital signal that is set as a frequency and indicates the frequency of the set oscillation frequency can be set and output as an oscillation frequency setting 0/1 signal F.

  The switching output circuit 14 performs a high-frequency switching operation by the FET gate input signal H that is alternately input to the gate terminals of the high-side FETs 141a and 141b and the gate terminals of the low-side FETs 142a and 142b, and switches the DC current J. It is converted into high frequency power K.

  That is, the DC power J applied to the switching circuit 14 is converted into the switching high-frequency power K by the FET gate input signal H that switches between the high side and the low side according to the oscillation frequency set by the DDS 28, and the output transformer 16, An ultrasonic output M is applied to the ultrasonic transducer 110 via the power factor correction circuit 18.

  In the ultrasonic oscillator 10, the power factor correction circuit 18 is connected in parallel to the ultrasonic transducer 110.

In the above configuration, when the ultrasonic output M is applied to the ultrasonic transducer 110, the ultrasonic wave is propagated from the ultrasonic transducer 110 attached to the bottom 104a of the cleaning tank 104 to the internal cleaning liquid 102 to be cleaned. The object 200 can be washed.

  The ultrasonic vibrator 110 can sweep a predetermined frequency width at a predetermined time interval with respect to the ultrasonic wave irradiated to the cleaning liquid 102 and the object 200, that is, the frequency of the ultrasonic output M, and The output power value calculated value E corresponding to the ultrasonic output M at each frequency during the sweep is compared, and the frequency when the ultrasonic power M is maximum, that is, the output power value calculated value E is the maximum. An ultrasonic oscillator 10 that can be tracked as a set oscillation frequency is connected.

  In other words, the ultrasonic oscillator 10 sweeps the frequency of the ultrasonic wave to be radiated at a predetermined frequency width every predetermined time, and at that time, the output transformer secondary side switching high-frequency power L at each frequency being swept is obtained. In comparison, it is configured such that it can be driven by setting the frequency when the power is maximum, that is, when the ultrasonic output M is maximum as the set oscillation frequency.

  That is, the ultrasonic oscillator 10 sweeps the oscillation frequency of the ultrasonic wave to be irradiated at a predetermined time interval by a predetermined frequency width, and the output transformer secondary side switching high frequency power L at each frequency being swept is multiplied by the multiplier 24. The oscillation frequency when the output power value calculation voltage E is maximum is set as the set oscillation frequency by the microcomputer 26, and the switching circuit 14 sets the switching frequency of the set oscillation frequency. The power K is output, and this cycle is repeated, and tracking is performed so that the oscillation frequency at which the output transformer secondary side switching high frequency power L is always the maximum becomes the set oscillation frequency.

  As described above, the microcomputer 26 sets the oscillation frequency of the ultrasonic wave emitted from the ultrasonic transducer 110 to each frequency for sweeping a predetermined frequency width at predetermined time intervals by a program. Are generated and passed to the DDS 28 side.

  Here, the above-described initial set oscillation frequency is a frequency that becomes the center of the oscillation frequency of the ultrasonic wave that is irradiated while sweeping a predetermined frequency width from the ultrasonic vibrator 110 to the cleaning liquid 102 and the cleaning object 200, for example, 20 kHz to 3 MHz may be used.

  Further, the predetermined frequency width when sweeping the oscillation frequency may be a value of 1% to 50% of the initial set oscillation frequency, for example, and 1% to 50% of the initial set oscillation frequency is the center. The frequency width of the value may be swept to search for a frequency that maximizes the ultrasonic output.

  Specifically, when the initial oscillation frequency is 30 kHz and the predetermined frequency width when sweeping the oscillation frequency is 10% of the initial oscillation frequency, the frequency width of 3 kHz is swept around 30 kHz. That is, the frequency band of 28.5 kHz to 31.5 kHz is swept.

  The predetermined time interval until the next search is performed after searching for the frequency at which the ultrasonic output is maximum and setting the set oscillation frequency may be, for example, 5 seconds to 600 seconds.

Next, the operation of the above-described ultrasonic oscillator 10 will be described in more detail. When applying high-frequency power to both poles of the ultrasonic vibrator 110 as a load, the ultrasonic oscillator 10 was applied from the AC power supply 12. The AC power I is converted into DC power J by the rectifier circuit 12, and the converted DC power J is converted into switching high-frequency power K by the switching function of the switching output circuit 14.

  Here, the microcomputer 26 outputs an oscillation frequency setting 0/1 signal F for causing the DDS 28 to recognize the set oscillation frequency, and an oscillation frequency setting signal for causing the DDS 28 to recognize the frequency to be swept, such an oscillation frequency setting 0/1 signal. When F and the oscillation frequency setting signal are input to the DDS 28, the DDS 28 outputs a rectangular wave oscillation frequency setting signal G to the drive circuit 30.

  Then, the drive circuit 30 to which the oscillation frequency setting signal G is input has an FET gate input amplified to a voltage that can drive the gate terminals of the high-side FETs 141a and 141b and the gate terminals of the low-side FETs 142a and 142b of the switching output circuit 14. The signal H is alternately input to the gate terminals of the high-side FETs 141a and 141b and the gate terminals of the low-side FETs 142a and 142b of the switching output circuit 14 at a set frequency or a sweeping frequency. J is converted into switching high-frequency power K.

  The switching high-frequency power K is stepped up or down by the output transformer 16 and converted into the output transformer secondary-side switching high-frequency power L. After that, the output transformer secondary-side switching high-frequency power L passes through the power factor correction circuit 18. The power factor corrected and the power factor-corrected output transformer secondary-side switching high frequency power ultrasonic output M is applied to the ultrasonic transducer 110.

Here, in the ultrasonic oscillator 10, in order to measure whether the oscillation frequency oscillated in the ultrasonic oscillator 10 is different from the resonance frequency due to the influence of various conditions such as the usage environment of the ultrasonic oscillator 10. As described above, a predetermined frequency width is swept around the initially set oscillation frequency at predetermined time intervals.

  That is, the output transformer secondary-side switching high-frequency voltage A that is the voltage portion of the output transformer secondary-side switching high-frequency power L output from the output transformer 16 is detected by the voltage value detection circuit 20 and converted into the output voltage value detection voltage C. In addition, the output transformer secondary-side switching high-frequency current B, which is the current portion of the output transformer secondary-side switching high-frequency power L output from the output transformer, is detected by the current value detection circuit 22 and converted into an output current value detection voltage. .

  The converted output voltage value detection voltage C and output current value detection voltage D are input to the multiplier 28, and the multiplier 28 multiplies the output voltage value detection voltage C and the output current value detection voltage D to output power. A value detection voltage E is calculated, and the calculated output power value detection voltage E is output to the microcomputer 26.

  Then, the microcomputer 26 sweeps a predetermined frequency width around the initially set oscillation frequency, measures the output power value detection voltage E at each frequency, and among the measurement results, the output power value detection voltage E is the maximum. In other words, the oscillation frequency when the ultrasonic output M is maximum is set as the set transmission frequency which is the oscillation frequency until the next sweep.

  Further, the conversion from the output voltage value detection voltage C and the output current value detection voltage D in the voltage value detection circuit 20 and the current value detection circuit 22 to the setting of the set frequency in the microcomputer 26 are performed at predetermined time intervals. Is set to do.

That is, according to the ultrasonic oscillator 10 described above, the set oscillation frequency can always be set to the frequency at which the output is maximized by performing the frequency sweep operation for the purpose of investigating the output power value at predetermined time intervals.

  In the ultrasonic oscillator 10, the power factor correction circuit 18 is connected in parallel to the ultrasonic transducer 110 so that the output is maximized.

As described above, according to the ultrasonic oscillator 10 of the present invention, the output transformer secondary-side switching high frequency that is the voltage portion of the output transformer secondary-side switching high-frequency power L that is the ultrasonic output M is corrected. The voltage A and the output transformer secondary switching high-frequency voltage B, which is the current part, are converted into an output voltage value detection voltage C and an output current value detection voltage D, respectively, and the converted output voltage value detection voltage C and output current value are converted. The operation of calculating the output power value detection voltage E from the detection voltage D is performed by sweeping the frequency with a predetermined frequency width around the initially set oscillation frequency at a predetermined time interval, and the output power value at each frequency at the time of sweeping The frequency at which the detection voltage becomes maximum is set as the oscillation frequency.

  That is, in the ultrasonic generator 10, the output power value detection voltage E is measured and the frequency when the output power value detection voltage E is the maximum is set as the oscillation frequency, so that the frequency is tracked by PLL control. Compared to such a conventional method, the method of measuring the output of the ultrasonic generator is straightforward, so that an efficient ultrasonic output can be stably obtained.

Next, an ultrasonic oscillator according to a second embodiment of the present invention will be described with reference to FIGS.

  Here, FIG. 4 is a block diagram for explaining the configuration of an ultrasonic oscillator according to the second embodiment of the present invention, and FIG. 5 shows an ultrasonic transducer from a switching circuit in the ultrasonic oscillator shown in FIG. The schematic circuit explanatory drawing which shows the principal part of the electric power transmission path | route leading to is shown.

  Similarly to the ultrasonic oscillator 10 according to the first embodiment of the present invention, the ultrasonic oscillator 40 according to the second embodiment of the present invention monitors the output transformer secondary-side switching high-frequency power L and the resonance frequency. The embodiment which tracks is shown.

  However, the ultrasonic oscillator 10 according to the first embodiment of the present invention has a circuit configuration in which the power factor correction circuit 18 is arranged at the subsequent stage of the output transformer 16, whereas the second embodiment of the present invention. The ultrasonic oscillator 40 according to the embodiment has a circuit configuration in which the power factor correction circuit 18 is arranged in front of the output transformer 16, and the ultrasonic oscillator 10 according to the first embodiment of the present invention and the ultrasonic oscillator 10 according to the present invention. Different from the ultrasonic oscillator 40 according to the second embodiment.

  Therefore, according to this ultrasonic oscillator 40, the switching high frequency power K is power factor corrected by the power factor correction circuit 18, and then boosted or lowered by the output transformer 16 to transform the transformer secondary side switching high frequency power L, that is, ultrasonic output. Will be converted to M.

  Also in such an ultrasonic oscillator 40, the same effects as those of the ultrasonic oscillator 10 described above can be obtained.

Next, an ultrasonic oscillator according to a third embodiment of the present invention will be described with reference to FIG.

  FIG. 6 is a block diagram for explaining the configuration of an ultrasonic oscillator according to the third embodiment of the present invention. The ultrasonic oscillator 50 according to the third embodiment of the present invention includes a bridge circuit. An embodiment in which the bridge output power N of 52 is monitored and the resonance frequency is tracked is shown.

  In addition, a piezoelectric ultrasonic transducer 120 is connected to the ultrasonic oscillator 50 as an ultrasonic transducer to which high frequency power is applied by the ultrasonic oscillator 50.

  Further, in the ultrasonic oscillator 50, an inductor 18 ′ is connected in parallel as a power factor correction circuit to the bridge circuit 52 including the piezoelectric ultrasonic transducer 120.

  Such an ultrasonic oscillator 50 sweeps a predetermined frequency width at a predetermined time interval for the frequency of ultrasonic waves to be irradiated, and compares the bridge output power N at each frequency being swept at that time, That is, it is formed so that it can be driven by setting the frequency when the ultrasonic output M is maximum as the set oscillation frequency.

  More specifically, the ultrasonic oscillator 50 is an ultrasonic oscillator for applying high-frequency power to both electrodes of the piezoelectric ultrasonic transducer 120 that is a load, and is connected to the AC power source 106.

  The ultrasonic oscillator 50 includes a bridge circuit 52 having a bridge output power detection resistor 52a for detecting the vibration speed of the piezoelectric ultrasonic transducer 120 as the bridge output power N, and a voltage portion of the bridge output power N. A voltage output detection circuit 20 ′ that detects a bridge output voltage O and converts it to a bridge output voltage value detection voltage Q, and a bridge output current P detection that detects a bridge output current P that is a current portion of the bridge output power N. A current value detection circuit 22 'for converting to voltage R, and a multiplier for inputting a bridge output voltage value detection voltage Q and a bridge output current value detection voltage R and multiplying them to calculate a bridge output power value calculation voltage S 24 'and a bridge output at each oscillation frequency when a predetermined frequency width centered on the initially set oscillation frequency is swept through at predetermined time intervals. The power value calculation voltage S is stored, and the oscillation frequency when the bridge output power value calculation voltage S is the highest among the stored bridge output power value calculation voltages S is set as the set oscillation frequency. And a microcomputer 26 ′ as oscillation frequency setting means for obtaining and outputting a digital signal indicating the frequency as an oscillation frequency setting 0/1 signal F.

  In the ultrasonic oscillator 50, the oscillation frequency processing means is constructed by the microcomputer 26 ', the DDS 28, and the drive circuit 30.

Here, the microcomputer 26 ′ will be described in more detail. For sweeping a predetermined frequency width at predetermined time intervals by a program based on the oscillation frequency of the ultrasonic wave irradiated from the piezoelectric ultrasonic transducer 120. When an oscillation frequency setting signal capable of forming a frequency can be output and the bridge output power value calculation voltage S at each frequency during the sweep is compared and the bridge output power value calculation voltage S is maximum after the sweep Is set as the set oscillation frequency, and a digital signal indicating the set oscillation frequency can be set and output as the oscillation frequency setting 0/1 signal F.

  That is, the microcomputer 26 ′ sweeps a predetermined frequency width around the initially set oscillation frequency at a predetermined time interval, measures the bridge output power value calculation voltage S at each oscillation frequency, and the ultrasonic output M is The maximum oscillation frequency is set as the set oscillation frequency.

  That is, the ultrasonic oscillator 50 sweeps a predetermined frequency width at a predetermined time interval for the oscillation frequency of the ultrasonic wave to irradiate, and the bridge output power N at each frequency being swept is calculated by the multiplier 24 ′. The oscillation frequency at the time when the bridge output power value calculation voltage S is maximum is set as the set oscillation frequency by the microcomputer 26 ′, and the switching high frequency power at the set oscillation frequency is set by the switching circuit 14. K is output, and this cycle is repeated, and tracking is performed so that the oscillation frequency at which the bridge output power N is always the maximum becomes the set oscillation frequency.

  In other words, the ultrasonic oscillator 50 performs a frequency sweep operation for the purpose of investigating the output power value at an arbitrary time interval so that the set oscillation frequency is always a frequency at which the output is maximized.

  In the ultrasonic oscillator 50, the ultrasonic output M is applied to the bridge circuit 52 including the piezoelectric ultrasonic transducer 120.

  In the ultrasonic oscillator 50, an inductor 18 'is connected in parallel with the piezoelectric ultrasonic transducer 120 as a power factor correction circuit so that the output is maximized.

Next, an ultrasonic oscillator according to a fourth embodiment of the invention will be described with reference to FIG.

  Here, FIG. 7 shows a block diagram of an ultrasonic oscillator according to the fourth embodiment of the present invention.

  Similarly to the ultrasonic oscillator 50 according to the third embodiment of the present invention, the ultrasonic oscillator 60 according to the fourth embodiment of the present invention monitors the bridge output power N of the bridge circuit 52 and sets the resonance frequency. The embodiment which tracks is shown.

  However, in the ultrasonic oscillator 40 according to the third embodiment of the present invention, the inductor 18 ′ is connected in parallel as a power factor correction circuit to the bridge circuit 52 including the piezoelectric ultrasonic transducer 120. On the other hand, in the ultrasonic oscillator 60 according to the fourth embodiment of the present invention, the inductor 18 ′ is connected in series as a power factor correction circuit to the bridge circuit 52 including the piezoelectric ultrasonic transducer 120. In that respect, the ultrasonic oscillator 50 according to the third embodiment of the present invention is different from the ultrasonic oscillator 60 according to the fourth embodiment of the present invention.

  That is, in the ultrasonic oscillator 60, the inductor 18 ′ is connected in series with the piezoelectric ultrasonic transducer 120 as a power factor correction circuit so that the output is maximized. Since it is the same as that of the oscillator 50, detailed description thereof is omitted.

Next, an ultrasonic oscillator according to a fifth embodiment of the invention will be described with reference to FIG.

  FIG. 8 is a block diagram for explaining the configuration of an ultrasonic oscillator according to the fifth embodiment of the present invention. The ultrasonic oscillator 70 according to the fifth embodiment of the present invention includes a bridge circuit. An embodiment in which the bridge output power N of 52 is monitored and the resonance frequency is tracked is shown.

  In addition, a magnetostrictive ultrasonic transducer 130 is connected to the ultrasonic oscillator 70 as an ultrasonic transducer to which high frequency power is applied by the ultrasonic oscillator 70.

  In the ultrasonic oscillator 70, a capacitor 18 ″ is connected in parallel as a power factor correction circuit to the bridge circuit 52 including the magnetostrictive ultrasonic transducer 130.

  In such an ultrasonic oscillator 70, the ultrasonic oscillator 50 connected to the ultrasonic oscillator 50 is the piezoelectric ultrasonic vibrator 120, and the inductor 18 ′ is replaced with the piezoelectric ultrasonic vibrator 120 as a power factor correction circuit. In contrast, the ultrasonic transducer is connected to the magnetostrictive ultrasonic transducer 130 in parallel, and a capacitor 18 ″ is connected in parallel to the magnetostrictive ultrasonic transducer 130 as a power factor correction circuit. The other operational effects are the same as those of the ultrasonic oscillator 50, and the detailed description thereof will be omitted.

Next, an ultrasonic oscillator according to a sixth embodiment of the invention will be described with reference to FIG.

  FIG. 9 is a block diagram for explaining an ultrasonic oscillator according to the sixth embodiment of the present invention.

  Similarly to the ultrasonic oscillator 70 according to the fifth embodiment of the present invention, the ultrasonic oscillator 80 according to the sixth embodiment of the present invention monitors the bridge output power N of the bridge circuit 52 and sets the resonance frequency. The embodiment which tracks is shown.

  However, in the ultrasonic oscillator 70 according to the fifth embodiment of the present invention, a capacitor 18 ″ is connected in parallel as a power factor correction circuit to the bridge circuit 52 including the magnetostrictive ultrasonic transducer 130. On the other hand, in the ultrasonic oscillator 80 according to the sixth embodiment of the present invention, a capacitor 18 ″ is connected in series as a power factor correction circuit to the bridge circuit 52 including the magnetostrictive ultrasonic transducer 130. The ultrasonic oscillator 70 according to the fifth embodiment of the present invention is different from the ultrasonic oscillator 80 according to the sixth embodiment of the present invention in that they are connected to each other.

  That is, in the ultrasonic oscillator 80, the capacitor 18 ″ is connected in series with the magnetostrictive ultrasonic transducer 130 as a power factor correction circuit so that the output is maximized. Since it is the same as the sound wave oscillator 70, the detailed description is abbreviate | omitted.

As described above, according to the ultrasonic oscillator of the present invention, the output power value detection voltage measured at a predetermined time interval or the oscillation frequency corresponding to the bridge output power value detection voltage is managed efficiently. Ultrasonic output can be obtained.

The embodiment described above can be changed as shown in the following (1) to (4).

(1) In the third embodiment, the fourth embodiment, the fifth embodiment, and the fourth embodiment described above, an inductor 18 ′ or a capacitor is used as a power factor correction circuit after the output transformer. The case where 18 ″ is arranged has been described, but the present invention is not limited to this. Of course, an inductor 18 ′ or a capacitor 18 ″ may be arranged as a power factor correction circuit before the output transformer. Good (2) In the first embodiment and the second embodiment described above, the power factor correction circuit 18 is configured to be connected in parallel to the ultrasonic transducer 110. However, the present invention is not limited to this. Of course, the power factor correction circuit 18 may be connected to the ultrasonic transducer 110 in series.

  (3) In the description of the second embodiment, the third embodiment, the fourth embodiment, the fifth embodiment and the sixth embodiment described above, the initial set frequency and the oscillation frequency The description of the specific example of the predetermined frequency width and the predetermined time interval when sweeping is omitted, but for example, it may be set similarly to the first embodiment. That is, the initial set oscillation frequency may be, for example, 20 kHz to 3 MHz, the predetermined frequency width may be, for example, a value of 1% to 50% of the initial set oscillation frequency, and the predetermined time interval is, for example, What is necessary is just to set it as 5 seconds-600 seconds.

  (4) You may make it combine suitably the embodiment shown above and the modification shown in said (1) thru | or (3).

  The present invention can be used as an ultrasonic generator for various ultrasonic apparatuses such as an ultrasonic cleaning apparatus and an ultrasonic measurement apparatus.

FIG. 1 is an explanatory diagram of a configuration of an ultrasonic cleaning apparatus using an ultrasonic transducer to which high-frequency power is applied from an ultrasonic oscillator. FIG. 2 is an explanatory block diagram of the ultrasonic oscillator according to the first embodiment of the present invention. FIG. 3 is a schematic circuit explanatory diagram showing the main part of the power transmission path from the switching circuit to the ultrasonic transducer in the ultrasonic oscillator shown in FIG. FIG. 4 is an explanatory block diagram of an ultrasonic oscillator according to the second embodiment of the present invention. FIG. 5 is a schematic circuit explanatory diagram showing the main part of the power transmission path from the switching circuit to the ultrasonic transducer in the ultrasonic oscillator shown in FIG. FIG. 6 is a block diagram for explaining an ultrasonic oscillator according to the third embodiment of the present invention. FIG. 7 is a block diagram for explaining an ultrasonic oscillator according to the fourth embodiment of the present invention. FIG. 8 is a block diagram for explaining an ultrasonic oscillator according to the fifth embodiment of the present invention. FIG. 9 is a block diagram for explaining an ultrasonic oscillator according to the sixth embodiment of the present invention.

Explanation of symbols

10, 40, 50, 60, 70, 80 Ultrasonic oscillator 12 Rectifier circuit 14 Switching output circuit 16 Output transformer 18, 18 ', 18''Power factor correction circuit 20, 20' Voltage value detection circuit 22, 22 'Current value Detection circuit 24, 24 'multiplier 26, 26' microcomputer 28 DDS (Direct Digital Synthesizer)
DESCRIPTION OF SYMBOLS 30 Drive circuit 52 Bridge circuit 52a Resistance for bridge output electric power value detection 100 Ultrasonic cleaning apparatus 102 Cleaning liquid 104 Cleaning bowl 104a Bottom part 106 AC power supply 108 Ultrasonic oscillator 110 Ultrasonic vibrator 120 Piezoelectric ultrasonic vibrator 130 Magnetostrictive ultrasonic wave Vibrators 141a, 141b High-side FETs (Field Effect Transistors)
142a, 142b Low-side FET
A Output transformer secondary side switching high frequency voltage B Output transformer secondary side switching high frequency current C Output voltage value detection voltage D Output current value detection voltage E Output power value calculation voltage F Oscillation frequency setting 0/1 signal G Oscillation frequency setting signal H FET gate input signal I AC power J DC power K Switching high frequency power L Output transformer secondary side switching high frequency power M Ultrasonic output N Bridge output power O Bridge output voltage P Bridge output current Q Bridge output voltage value detection voltage R Bridge output current Value detection voltage S Bridge output power value calculation voltage

Claims (8)

In an ultrasonic oscillator that applies high-frequency power to both poles of an ultrasonic transducer,
A switching output circuit that generates switching high-frequency power by alternately switching DC power between a high side and a low side at a set oscillation frequency;
An output transformer for boosting or stepping down the voltage of the switching high-frequency power generated by the switching output circuit and outputting the output transformer secondary-side switching high-frequency power;
The output transformer secondary side switching high frequency voltage which is the voltage part of the output transformer secondary side switching high frequency power output from the output transformer and the output transformer secondary side switching high frequency which is the current part of the output transformer secondary side switching high frequency power. A power factor correction circuit that performs power factor correction to eliminate the phase difference from the current and apply it to the ultrasonic transducer;
A voltage value detection circuit that detects an output transformer secondary-side switching high-frequency voltage, which is a voltage portion of the output transformer secondary-side switching high-frequency power output from the output transformer, and converts it into an output voltage value detection voltage;
A current value detection circuit that detects an output transformer secondary-side switching high-frequency current that is a current portion of the output transformer secondary-side switching high-frequency power output from the output transformer, and converts it into an output current value detection voltage;
A multiplier for multiplying the output voltage value detection voltage converted by the voltage value detection circuit and the output current value detection voltage converted by the current value detection circuit to calculate an output power value detection voltage;
A frequency at which the set oscillation frequency is controlled to be swept at a predetermined time interval and a predetermined frequency width, and the output power value detection voltage at each oscillation frequency calculated by the multiplier is maximized. And an oscillation frequency setting means for setting the oscillation frequency as an oscillation frequency. In an ultrasonic oscillator that applies high-frequency power to both poles of an ultrasonic transducer,
A switching output circuit that generates switching high-frequency power by alternately switching DC power between a high side and a low side at a set oscillation frequency;
A power factor correction circuit for power factor correcting the switching high frequency power generated by the switching output circuit;
An output transformer that boosts or steps down the switching high-frequency power corrected by the power factor by the power factor correction circuit and outputs the switching high-frequency power as an output transformer secondary-side switching high-frequency power;
A voltage value detection circuit that detects an output transformer secondary-side switching high-frequency voltage, which is a voltage portion of the output transformer secondary-side switching high-frequency power output from the output transformer, and converts it into an output voltage value detection voltage;
A current value detection circuit that detects an output transformer secondary-side switching high-frequency current that is a current portion of the output transformer secondary-side switching high-frequency power output from the output transformer, and converts it into an output current value detection voltage;
A multiplier for multiplying the output voltage value detection voltage converted by the voltage value detection circuit and the output current value detection voltage converted by the current value detection circuit to calculate an output power value detection voltage;
A frequency at which the set oscillation frequency is controlled to be swept at a predetermined time interval and a predetermined frequency width, and the output power value detection voltage at each oscillation frequency calculated by the multiplier is maximized. And an oscillation frequency setting means for setting the oscillation frequency as an oscillation frequency. In an ultrasonic oscillator that applies high-frequency power to both poles of an ultrasonic transducer,
A switching output circuit that generates switching high-frequency power by alternately switching DC power between a high side and a low side at a set oscillation frequency;
An output transformer for boosting or stepping down the voltage of the switching high-frequency power generated by the switching output circuit and outputting the output transformer secondary-side switching high-frequency power;
The output transformer secondary side switching high frequency voltage which is the voltage part of the output transformer secondary side switching high frequency power output from the output transformer and the output transformer secondary side switching high frequency which is the current part of the output transformer secondary side switching high frequency power. A power factor correction circuit that performs power factor correction to eliminate the phase difference from the current and apply it to the ultrasonic transducer;
A bridge output power detection resistor for detecting, as a bridge output power, a vibration speed of the ultrasonic transducer that vibrates by applying the output transformer secondary side switching high frequency power that has been power factor corrected by the power factor correction circuit;
A voltage value detection circuit that detects a bridge output voltage, which is a voltage portion of the bridge output power detected by the bridge output power detection resistor, and converts it into a bridge output voltage value detection voltage;
A current value detection circuit that detects a bridge output current, which is a current portion of the bridge output power detected by the bridge output power detection resistor, and converts it into a bridge output current value detection voltage;
A multiplier for calculating a bridge output power value calculation voltage by multiplying the bridge output voltage value detection voltage converted by the voltage value detection circuit and the bridge output current value detection voltage converted by the current value detection circuit;
Control is performed so that the set oscillation frequency is swept at a predetermined time interval and a predetermined frequency width, and the bridge output power value calculation voltage at each oscillation frequency by the sweep calculated by the multiplier is maximized. An ultrasonic oscillator characterized by comprising oscillation frequency setting means for setting a frequency as an oscillation frequency. In an ultrasonic oscillator that applies high-frequency power to both poles of an ultrasonic transducer,
A switching output circuit that generates switching high-frequency power by alternately switching DC power between a high side and a low side at a set oscillation frequency;
A power factor correction circuit for power factor correcting the switching high frequency power generated by the switching output circuit;
An output transformer that boosts or steps down the switching high-frequency power corrected by the power factor by the power factor correction circuit and outputs the switching high-frequency power as an output transformer secondary-side switching high-frequency power;
A bridge output power detection resistor that detects a vibration speed of the ultrasonic transducer that vibrates by applying an output transformer secondary side switching high frequency power output from the output transformer as a bridge output power;
A voltage value detection circuit that detects a bridge output voltage, which is a voltage portion of the bridge output power detected by the bridge output power detection resistor, and converts it into a bridge output voltage value detection voltage;
A current value detection circuit that detects a bridge output current, which is a current portion of the bridge output power detected by the bridge output power detection resistor, and converts it into a bridge output current value detection voltage;
A multiplier for calculating a bridge output power value calculation voltage by multiplying the bridge output voltage value detection voltage converted by the voltage value detection circuit and the bridge output current value detection voltage converted by the current value detection circuit;
Control is performed so that the set oscillation frequency is swept at a predetermined time interval and a predetermined frequency width, and the bridge output power value calculation voltage at each oscillation frequency by the sweep calculated by the multiplier is maximized. An ultrasonic oscillator characterized by comprising oscillation frequency setting means for setting a frequency as an oscillation frequency. The ultrasonic oscillator according to any one of claims 1, 2, 3 or 4,
The ultrasonic oscillator, wherein the power factor correction circuit is connected in parallel to the ultrasonic transducer. The ultrasonic oscillator according to any one of claims 1, 2, 3 or 4,
The ultrasonic oscillator, wherein the power factor correction circuit is connected in series to the ultrasonic transducer. The ultrasonic oscillator according to any one of claims 1, 2, 3, 4, 5 or 6,
The ultrasonic transducer is a piezoelectric ultrasonic transducer,
The ultrasonic oscillator, wherein the power factor correction circuit is an inductor. The ultrasonic oscillator according to any one of claims 1, 2, 3, 4, 5 or 6,
The ultrasonic transducer is a magnetostrictive ultrasonic transducer,
The ultrasonic power oscillator, wherein the power factor correction circuit is a capacitor.

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