JP4039627B2 - Ultrasonic generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an ultrasonic generator that vibrates biological tissue with ultrasonic energy generated between conductors.
[0002]
[Prior art]
  In general, this type of ultrasonic generator has a built-in ultrasonic vibrator used for facial instruments, medical instruments, industrial use, etc., and the ultrasonic energy generated from this ultrasonic vibrator is transferred between the conductors to the living body. To give. The ultrasonic vibrator has an overtone (harmonic) vibration mode in addition to the fundamental vibration mode. For example, a vibrator having a fundamental wave of 1 MHz can be vibrated at an odd multiple of 3 MHz or 5 MHz. Is possible.
[0003]
  On the other hand, the living body, that is, the human body can transmit vibration to a deeper part when a lower frequency is given than a higher frequency, and the higher frequency can vibrate the shallow part of the human body intensively, for example, about 1 MHz. Low frequency ultrasonic waves are used for abdominal slimming (fat free burning), and high frequency ultrasonic waves of about 3 MHz are used for facial beauty. Therefore, if the vibration (frequency) mode can be instantaneously switched electronically in an ultrasonic generator with a built-in ultrasonic transducer, vibration up to the deep part at the low frequency by the fundamental wave vibration mode and overtone vibration mode Combined with the concentrated vibration to the shallow part at a high frequency, the effect of giving vibrations at a plurality of different frequencies at the same time can be obtained. Moreover, such instantaneous switching of vibration modes not only has the effect of treating a wide range from the shallow part to the deep part of the living body at the same time, but also energy to a part that cannot be avoided when a stimulus signal is given in a single vibration mode. The harmful effects of concentration can be reduced.
[0004]
  The internal configuration of a conventional ultrasonic generator is composed of a type in which an ultrasonic transducer is placed in a feedback loop of a drive circuit, and the ultrasonic transducer is vibrated by a current caused by so-called self-excited oscillation, and a power amplifier is provided in a separately excited oscillation circuit. By providing a connected oscillation output circuit, mechanically switching a matching circuit having a filter action, and providing an output signal output at a plurality of frequencies from the oscillation output circuit to a single ultrasonic transducer, Two types are known in which this ultrasonic vibrator vibrates with a fundamental wave or overtone. In particular, the latter configuration has an internal configuration suitable for achieving the above-described effect. As a related technology, for example, Patent Document 1 discloses that the output of the oscillation circuit is a high-frequency power by a power amplifier in the next stage. There has been disclosed an ultrashort wave treatment device that can treat two points simultaneously by amplifying and alternately supplying amplifier outputs to two output terminals via a matching circuit.
[0005]
[Patent Literature]
  Japanese Patent Laid-Open No. 2002-165892
[0006]
[Problems to be solved by the invention]
  In the configuration of Patent Document 1, when a single ultrasonic vibrator is provided at the output stage of the matching circuit and a plurality of frequencies are to be vibrated from the ultrasonic vibrator, a filter action is performed according to each frequency. It is necessary to switch the matching circuit having In that case, since a very large electric power (several W to several tens W) having a high impedance and a low impedance is handled, conventionally, the matching circuit has to be mechanically switched by a switch or a relay contact. Therefore, frequent mechanical switching cannot be performed as long as mechanical parts are used, and a sufficient effect of simultaneously treating a wide range from a shallow part to a deep part of a living body cannot be obtained.
[0007]
  Therefore, in view of the above problems, the present invention provides an ultrasonic generator that can simultaneously treat a wide range from a shallow part to a deep part of a living body using a single ultrasonic transducer. Objective.
[0008]
[Means for Solving the Problems]
  An ultrasonic generator according to the present invention supplies output signals of different frequencies from an oscillation output circuit to a single ultrasonic transducer through a matching circuit, and applies ultrasonic energy from the ultrasonic transducer to a living body. In the sound wave generator,The oscillation output circuit includes: an oscillation circuit that generates a rectangular wave oscillation signal having any one frequency among frequencies corresponding to a fundamental vibration mode, a harmonic vibration mode, and a spurious response of the ultrasonic vibrator; An attenuator that attenuates each oscillation signal of each frequency independently; a variable frequency filter comprising a filter that removes harmonics by shaping the oscillation signal of each frequency into a sine wave; and the variable frequency filter. An amplification circuit that amplifies a sinusoidal oscillation signal to be output and guides it to the matching circuit as the output signal. In order to switch and output the frequency of the oscillation signal, a division ratio switching signal is supplied to the oscillation circuit. A controller for adjusting the attenuation of the attenuator by monitoring the current flowing through the ultrasonic transducer and the current from the amplifier circuit. Equipped with a,The matching circuit includes theEach corresponding to the fundamental vibration mode, harmonic vibration mode, and spurious response of an ultrasonic transducerfrequencyThe output impedance of the amplifier circuit to the ultrasonic transducerAlignmentWhatIt is characterized by being.
[0009]
  In this case, the frequency of the output signal supplied from the oscillation output circuit isCorresponding to fundamental vibration mode, harmonic vibration mode, and spurious response of ultrasonic transducerEven if it changes frequently at high speed,MaThe etching circuit iseachThe matching between the oscillation output circuit and the ultrasonic transducer can be optimized for the frequency output signal. Therefore, it is possible to simultaneously treat a wide range from the shallow part to the deep part of the living body by using a single ultrasonic transducer without any conventional mechanical parts.
[0010]
In addition, each sine wave oscillation signal output from the variable frequency filter is amplified to a predetermined power by an amplifier circuit and guided to a matching circuit. The matching circuit in this case is particularly a fundamental wave vibration of an ultrasonic transducer. At each frequency corresponding to the mode, harmonic vibration mode, and spurious response, the output impedance of the amplifier circuit can be matched to the ultrasonic transducer, so that the ultrasonic vibration can be performed in a stable state with almost no loss of the output signal. Can be supplied to children.
[0011]
In addition, the control means monitors the current flowing through the ultrasonic transducer and the state of the current from the amplifier circuit, and when the frequency of the oscillation signal is switched, a loss or gain error occurs in the oscillation output circuit or the matching circuit. In order to correct this, an attenuation amount switching signal for gain adjustment can be independently sent to the attenuator of the variable frequency filter. Therefore, the attenuation amount of each attenuator is feedback-controlled, and coupled with the fact that the matching circuit has matching characteristics corresponding to each frequency, it is possible to supply more stable ultrasonic energy from the ultrasonic transducer.
[0012]
Furthermore, by supplying a frequency division ratio switching signal from the control means to the oscillation circuit and frequently switching the frequency of the output signal from the oscillation output circuit, the adverse effect of energy concentration on a part of the living body can be eliminated.
[0013]
In the ultrasonic generator according to the present invention, in the above configuration, the control unit stores a natural resonance frequency of the ultrasonic transducer for each frequency and a total gain of the oscillation output circuit for each frequency. And storing the content stored in the non-volatile storage means to change the frequency division switching signal, the frequency component of the signal attenuated by the attenuator, and the frequency component of the signal filtered by the filter. The filter frequency variable signal is supplied.
[0014]
In this case, the characteristics of the ultrasonic transducer and the oscillation output circuit, which are adjusted while measuring the output waveform of each part in the inspection process after the manufacture of the device, are stored in the nonvolatile storage means. As a result, the control means reads out the stored contents from the non-volatile storage means as appropriate, and eliminates the manufacturing error of each ultrasonic transducer and the gain deviation of the oscillation output circuit so as to eliminate the optimum frequency division ratio switching signal and filter frequency. A variable signal can be supplied.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, an ultrasonic generator according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a schematic configuration of an ultrasonic generator, in which 1 is a single ultrasonic vibrator, and 2 is a pair of guides for applying ultrasonic energy generated from this ultrasonic vibrator to a living body (not shown). It is a child and the conductor 2 is detachably attached to the treatment site of the living body. On the other hand, as an oscillation output circuit 3 for supplying output signals of different frequencies to the ultrasonic transducer 1, in this embodiment, a wideband PLL (Phase Locked Loop) oscillator 4 corresponding to the oscillation circuit, and a sine wave generating means A variable frequency filter 5 and a broadband power amplifier circuit 6 corresponding to an amplifier circuit are connected in order. In addition, a matching circuit 7 is provided between the oscillation output circuit 3 and the ultrasonic transducer 1, but the matching circuit 7 of the present embodiment is an output signal having a different frequency supplied from the oscillation output circuit 3. The circuit is designed so that the oscillation output circuit 3 and the ultrasonic transducer 1 are matched over the entire area.
[0016]
  Here, referring to the block diagram of FIG. 2 as well, the wideband PLL oscillator 4 receives the frequency division ratio switching signal from the CPU 11 which is a control means to be described later, and the vibration mode (basic vibration) of the ultrasonic vibrator 1. Corresponding to the frequency of the mode), for exampleFrequency corresponding to spurious response1 / 2f,Frequency corresponding to fundamental vibration mode1f,Frequency corresponding to harmonic vibration modeAn oscillation signal having any one frequency of 3f is generated. Various other oscillation circuits are conceivable. Here, in order to change the frequency to a wide frequency (for example, 6 times or more) and make the frequency step finer, a special wide-band PLL oscillator 4 adapted to the frequency is used. Yes.
[0017]
  Further, the variable frequency filter 5 at the next stage prevents the ultrasonic transducer 1 from vibrating in an unnecessary mode and also prevents a rectangular wave generated from the wideband PLL oscillator 4 from flowing an invalid current. The harmonic signal is removed from the oscillating signal to form a sine wave, which corresponds to the oscillating signals of different frequencies from the wide-band PLL oscillator 4 as shown in FIG. 2, and a plurality of attenuators 15a, 15b, 15c. And a plurality of low-pass filters 16a, 16b, 16c, and a common buffer 17. Each of the attenuators 15a, 15b, and 15c is provided for gain adjustment for receiving an attenuation amount switching signal from the CPU 11 and attenuating a signal at a specific frequency component. In this embodiment, a wideband PLL is provided. In consideration of the selective output of oscillation signals having the frequencies of 1 / 2f, 1f, and 3f from the oscillator 4, three attenuators 15a that can attenuate the signals in these frequency components independently. 15b and 15c. The low-pass filters 16a, 16b, and 16c connected in series to the subsequent stages of the attenuators 15a, 15b, and 15c filter only signals at a specific frequency component, which are also 1 / 2f, 1f, and 3f. Signals below each frequency can be filtered. The frequency components of the signals attenuated by the attenuators 15a, 15b, and 15c and the frequency components of the signals that are filtered by the low-pass filters 16a, 16b, and 16c are all received by the filter frequency variable signal from the CPU 11, and individually. It can be changed according to the ultrasonic transducer 1. Further, the buffer 17 is for preventing a circuit connected to the output side of the variable frequency filter 5 from affecting the operation of the broadband PLL oscillator 4 from the variable frequency filter 5.
[0018]
  The low-pass filters 16a, 16b, and 16c are provided for shaping a rectangular wave oscillation signal into a sine wave to remove harmonics. For example, a single digital filter (DSP) is used as a device that performs the same function. May be used. However, in order to reduce the manufacturing cost, reduce the size, and reduce the power consumption, it is preferable to use a filter corresponding to each frequency as in this embodiment. The sinusoidal oscillation signal output from the variable frequency filter is amplified to a predetermined power by the broadband power amplification circuit 6 at the next stage, and then ultrasonically vibrated from the matching circuit 7 as an output signal of the oscillation output circuit 3. It is led to the child 1.
[0019]
  The CPU 11 includes frequency switching means 12 that outputs a frequency division ratio switching signal to the broadband PLL oscillator 4 in order to switch and output an oscillation signal having a plurality of frequencies from the broadband PLL oscillator 4, and to the ultrasonic transducer 1. Feedback monitoring means 13 for constantly monitoring the state of the flowing current and the current from the broadband power amplifier 6 is provided. If the feedback monitoring means 13 determines that the device is operating abnormally as a result of monitoring each current, the feedback monitoring means 13 forcibly stops the operation of the device or switches the oscillation signal when the frequency of the oscillation signal is switched. The loss and gain error of the output circuit 3 and the matching circuit 7 are calculated from the monitoring results of the currents, and the attenuation of the attenuators 15a, 15b, and 15c constituting the variable frequency filter 5 is adjusted.
[0020]
  Further, the CPU 11 includes an EEPROM 21 as nonvolatile storage means for storing the natural resonance frequency of the ultrasonic transducer 1 for each output frequency and the total gain of the oscillation output circuit 3 for each output frequency. The characteristics of the ultrasonic transducer 1 and the oscillation output circuit 3 are adjusted and stored in the EEPROM 21 while measuring the output waveform of each part in the inspection process after manufacturing the device. That is, the ultrasonic vibrator 1 has large variations in resonance frequency and capacitance (normally 10% or more), and when used in the overtone vibration mode with a frequency of 3f, for example, it is exactly an integral multiple of the basic frequency 1f. Therefore, it is necessary to store each resonance frequency in the EEPROM 21. As a result, the CPU 11 reads out the stored contents from the EEPROM 21 as appropriate, and optimizes the frequency division ratio switching signal and the filter frequency variable signal so as to eliminate the manufacturing error of each ultrasonic transducer 1 and the gain deviation of the oscillation output circuit 3. Can be supplied. In the present embodiment, a total of six pieces of information corresponding to different frequencies 1 / 2f, 1f, and 3f are stored in the EEPROM 21.
[0021]
  Next, the operation of the above configuration will be described. During the operation of the apparatus, the frequency switching means 12 of the CPU 11 outputs a frequency division ratio switching signal to the broadband PLL oscillator 4 at a timing of 100 times or more per second. In response, the broadband PLL oscillator 4 supplies an oscillation signal having a frequency component corresponding to each division ratio switching signal to the variable frequency filter 5. At this time, which frequency component is supplied at what ratio in each oscillation signal within a predetermined time can be adjusted by, for example, a switch (not shown) on the operation panel connected to the CPU 11 on the input side. As a result, an oscillation signal group having only single frequencies 1 / 2f, 1f, 3f can be supplied from the broadband PLL oscillator 4, or an oscillation in which three frequencies 1 / 2f, 1f, 3f are mixed at an appropriate ratio. The signal group can also be supplied from the broadband PLL oscillator 4.
[0022]
  When a rectangular wave oscillation signal having a frequency of 1 / 2f is output from the broadband PLL oscillator 4, this oscillation signal is optimally adjusted by the first attenuator 15a of the corresponding variable frequency filter 5, and the first low pass of the next stage is obtained. The harmonic component is removed by the filter 16a to form a sine wave. Similarly, the rectangular wave oscillation signal having a frequency of 1f output from the wideband PLL oscillator 4 is sine-wave shaped by the second low-pass filter 16b after optimal gain adjustment by the corresponding second attenuator 15b. The rectangular wave oscillation signal having the frequency 3f is sine wave-shaped by the third low-pass filter 16c after optimal gain adjustment is performed by the third attenuator 15c corresponding thereto. In this way, the output signals of the low-pass filters 16a, 16b, and 16c become only vibration mode waveforms that do not include harmonics, and pass through the common buffer 17.
[0023]
  afterwards,Output from variable frequency filter 5Each sinusoidal oscillation signal is amplified to a predetermined power by the broadband power amplifier 6 and guided to the matching circuit 7. The matching circuit 7 of the present embodiment particularly has the frequencies 1 / 2f, 1f, 3f.smellThus, the output impedance of the broadband power amplifier 6 can be matched with the low impedance ultrasonic transducer 1, therebyoutputThe signal can be supplied to the ultrasonic transducer 1 in a stable state with almost no loss. And eachoutputUltrasonic energy is generated from the ultrasonic vibrator 1 that resonates with the signal, and this ultrasonic energy is applied to the living body from between the conductors 2.
[0024]
  When the vibration mode of the ultrasonic vibrator 1 is only a high frequency (for example, 3f) component, the shallow part of the living body can be vibrated intensively, and this high frequency ultrasonic energy is used for, for example, facial cosmetics. can do. On the contrary, when the vibration mode of the ultrasonic transducer 1 is only a low frequency (for example, 1 / 2f) component, the deep part of the living body can be vibrated intensively, and this low frequency ultrasonic energy is applied to, for example, the abdomen. Can be used for slimming. Further, in this embodiment, the vibration mode of the ultrasonic transducer 1 can be switched in a short time so that the low frequency, the intermediate frequency (for example, 1f), and the high frequency have the same ratio. In this case, vibration can be uniformly applied from the shallow part to the deep part of the living body, and local concentration of ultrasonic energy can be avoided. Furthermore, the balance of the stimulation depth of the site to be used can be finely adjusted by making the time ratio of the frequency to be switched not variable and variable by an operating means such as a switch.
[0025]
  During this series of operations, the CPU 11 constantly monitors the state of the current flowing through the ultrasonic transducer 1 and the current from the broadband power amplifier 6 by the feedback monitoring unit 13. When a loss or a gain error occurs in the oscillation output circuit 3 or the matching circuit 7 when the frequency of the oscillation signal is switched, the attenuators 15a, 15b, and 15c of the variable frequency filter circuit 5 are corrected with respect to the loss or gain error. Attenuation amount switching signals for gain adjustment are sent independently. Thereby, the attenuation amount of each attenuator 15a, 15b, 15c is feedback-controlled, and the matching circuit 7 isCorresponding to each frequency 1 / 2f, 1f, 3fCombined with the matching characteristics, more stable ultrasonic energy can be supplied from the ultrasonic transducer 1.
[0026]
  As described above, according to the present embodiment, output signals of different frequencies from the oscillation output circuit 3 are supplied to the single ultrasonic transducer 1 via the matching circuit 7, and the ultrasonic transducer 1 transmits the ultrasonic wave to the living body. In an ultrasonic generator that applies sonic energy,The oscillation output circuit 3 is an oscillation circuit that generates a rectangular wave oscillation signal having any one of the frequencies corresponding to the fundamental vibration mode, the harmonic vibration mode, and the spurious response of the ultrasonic vibrator 1. Wideband PLL oscillator 4, attenuators 15 a, 15 b, 15 c that attenuate the oscillation signals of each frequency independently, and a low-pass filter 16 a that shapes the oscillation signals of each frequency into a sine wave and removes harmonics. A variable frequency filter 5 composed of 16b and 16c, and a broadband power amplifier circuit 6 as an amplifier circuit that amplifies the sine wave-like oscillation signal output from the variable frequency filter 5 and guides it to the matching circuit 7 as an output signal. In order to switch and output the frequency of the oscillation signal, a frequency division ratio switching signal is output to the broadband PLL oscillator 4, and Comprising monitoring the current from current and broadband power amplifier circuit 6 flowing through the ultrasonic transducer 1, the attenuator 15a, 15b, the CPU11 as a control means for adjusting the attenuation amount of 15c,The matching circuit 7Each corresponding to the fundamental vibration mode, harmonic vibration mode, and spurious response of the ultrasonic vibrator 1frequencyIn FIG. 4, the output impedance of the broadband power amplifier circuit 6 is applied to the ultrasonic vibrator 1.AlignmentIt is configured to make it.
[0027]
  In this case, even if the frequency of the output signal supplied from the oscillation output circuit 3 changes frequently at high speed., MaThe chucking circuit 7 can optimize the matching between the oscillation output circuit 3 and the ultrasonic transducer 1 for output signals of any frequency. Therefore, it is possible to simultaneously treat a wide range from the shallow part to the deep part of the living body by using the single ultrasonic transducer 1 without any conventional mechanical parts.
[0028]
Further, each sinusoidal oscillation signal output from the variable frequency filter 5 is amplified to a predetermined power by the broadband power amplifier 6 and guided to the matching circuit 7. The matching circuit 7 here is particularly an ultrasonic vibration. The output impedance of the broadband power amplifier 6 can be matched to the ultrasonic transducer 1 at each of the frequencies 1 / 2f, 1f, and 3f corresponding to the fundamental vibration mode, harmonic vibration mode, and spurious response of the child 1 Thus, the output signal can be supplied to the ultrasonic transducer 1 in a stable state with almost no loss.
[0029]
In addition, the CPU 11 monitors the state of the current flowing through the ultrasonic transducer 1 and the current from the broadband power amplifier 6, and when the frequency of the oscillation signal is switched, the oscillation output circuit 3 and the matching circuit 7 have a loss or gain. When an error occurs, an attenuation amount switching signal for gain adjustment is independently sent to the attenuators 15a, 15b, and 15c of the variable frequency filter 5 to correct the error. Thereby, the attenuation amount of each attenuator 15a, 15b, 15c is feedback-controlled, and combined with the matching circuit 7 having matching characteristics corresponding to the respective frequencies 1 / 2f, 1f, 3f, the ultrasonic vibration More stable ultrasonic energy can be supplied from the child 1.
[0030]
  Further, by supplying a frequency division ratio switching signal from the CPU 11 serving as the control means to the broadband PLL oscillator 4 and frequently switching the frequency of the output signal from the oscillation output circuit 3, there is also a problem that energy is concentrated on a part of the living body. Can be wiped out.
[0031]
Further, the CPU 11 of this embodiment includes the natural resonance frequency of the ultrasonic transducer 1 for each frequency 1 / 2f, 1f, 3f and the total gain of the oscillation output circuit 3 for each frequency 1 / 2f, 1f, 3f. EEPROM 21 as a non-volatile storage means for storing the data, and the storage contents from the EEPROM 21 are read out, and the frequency division ratio switching signal and the attenuators 15a and 15b are read out. , 15c and the low-pass filters 16a, 16b, 16c are supplied with a variable filter frequency signal for changing the frequency components of the signals to be filtered.
[0032]
In this case, the characteristics of the ultrasonic transducer 1 and the oscillation output circuit 3 are adjusted and stored in the EEPROM 21 while measuring the output waveform of each part in the inspection process after the device is manufactured. As a result, the CPU 11 reads out the stored contents from the EEPROM 21 as appropriate, and optimizes the frequency division ratio switching signal and the filter frequency variable signal so as to eliminate the manufacturing error of each ultrasonic transducer 1 and the gain deviation of the oscillation output circuit 3. Can be supplied.
[0033]
  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist of the present invention. The method of selecting a frequency in the embodiments is merely an example, and may be appropriately changed according to the design specifications of the apparatus. For example, the signal of the frequency 1 / 2f in the embodiment uses the spurious response of the ultrasonic vibrator 1 and normally does not vibrate at an even multiple, but can be used depending on the design of the ultrasonic vibrator 1. Become.
[0034]
【The invention's effect】
  Of the present inventionClaim 1An ultrasonic generator supplies output signals of different frequencies from an oscillation output circuit to a single ultrasonic transducer via a matching circuit, and applies ultrasonic energy to the living body from this ultrasonic transducer. InThe oscillation output circuit includes: an oscillation circuit that generates a rectangular wave oscillation signal having any one frequency among frequencies corresponding to a fundamental vibration mode, a harmonic vibration mode, and a spurious response of the ultrasonic vibrator; An attenuator that attenuates each oscillation signal of each frequency independently; a variable frequency filter comprising a filter that removes harmonics by shaping the oscillation signal of each frequency into a sine wave; and the variable frequency filter. An amplification circuit that amplifies a sinusoidal oscillation signal to be output and guides it to the matching circuit as the output signal. In order to switch and output the frequency of the oscillation signal, a division ratio switching signal is supplied to the oscillation circuit. A controller for adjusting the attenuation of the attenuator by monitoring the current flowing through the ultrasonic transducer and the current from the amplifier circuit. Equipped with a,The matching circuit includes theEach corresponding to the fundamental vibration mode, harmonic vibration mode, and spurious response of an ultrasonic transducerfrequencyThe output impedance of the amplifier circuit to the ultrasonic transducerAlignmentIt is characterized byThis makes it possible to simultaneously treat a wide range from the shallow part to the deep part of the living body using a single ultrasonic transducer.In addition, the output signal can be supplied to the ultrasonic transducer in a stable state with almost no loss, and more stable ultrasonic energy can be supplied from the ultrasonic transducer, and the adverse effects of energy concentration on a part of the living body can be eliminated. it can.
[0035]
  Of the present inventionClaim 2The ultrasonic generatorThe control unit includes a non-volatile storage unit that stores a natural resonance frequency of the ultrasonic transducer with respect to each frequency and a total gain of the oscillation output circuit with respect to each frequency, and stores from the non-volatile storage unit The contents are read, and the frequency division ratio switching signal, the frequency component of the signal attenuated by the attenuator, and the filter frequency variable signal for changing the frequency component of the signal filtered by the filter are supplied. An optimal frequency division ratio switching signal and a variable filter frequency signal can be supplied so as to eliminate manufacturing errors of the acoustic wave vibrator and gain deviation of the oscillation output circuit.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an outline of an ultrasonic generator according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a more detailed configuration of the variable frequency filter.
[Explanation of symbols]
  1 Ultrasonic vibrator
  3 Oscillation output circuit
  4 Broadband PLL oscillator (oscillation circuit)
  5Variable frequency filter
6 Broadband power amplifier circuit
  7Matching timesRoad
11 CPU (control means)
15a, 15b, 15c Attenuator
16a, 16b, 16c Low-pass filter (filter)
21 EEPROM (nonvolatile storage means)

Claims (2)

In an ultrasonic generator that supplies output signals of different frequencies from an oscillation output circuit to a single ultrasonic transducer via a matching circuit, and applies ultrasonic energy from the ultrasonic transducer to a living body.
The oscillation output circuit includes: an oscillation circuit that generates a rectangular wave oscillation signal having any one frequency among the frequencies corresponding to the fundamental vibration mode, the harmonic vibration mode, and the spurious response of the ultrasonic vibrator; ,
A variable frequency filter comprising an attenuator that attenuates each oscillation signal of each frequency independently, and a filter that shapes the oscillation signal of each frequency into a sine wave and removes harmonics;
An amplification circuit that amplifies a sinusoidal oscillation signal output from the variable frequency filter and guides it to the matching circuit as the output signal;
In order to switch and output the frequency of the oscillation signal, a frequency division ratio switching signal is output to the oscillation circuit, and a current flowing through the ultrasonic transducer and a current from the amplification circuit are monitored to reduce the attenuation Control means for adjusting the attenuation of the vessel,
The matching circuit is configured to match the output impedance of the amplification circuit to the ultrasonic transducer at each frequency corresponding to the fundamental vibration mode, the harmonic vibration mode, and the spurious response of the ultrasonic transducer. An ultrasonic generator characterized by.   The control unit includes a non-volatile storage unit that stores a natural resonance frequency of the ultrasonic transducer with respect to each frequency and a total gain of the oscillation output circuit with respect to each frequency, and stores from the non-volatile storage unit The contents are read, and the frequency division ratio switching signal, the frequency component of the signal attenuated by the attenuator, and the filter frequency variable signal for changing the frequency component of the signal filtered by the filter are supplied. The ultrasonic generator according to claim 1.

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