KR20190047796A - A Method for Optimizing a Frequency Condition of Generating a Ultrasound and A Ultrasound Generating Apparatus Having a Optimized Frequency Condition - Google Patents

Abstract

The present invention relates to a frequency optimization method for generating ultrasonic waves and an ultrasonic wave generating apparatus having a frequency optimization structure and, more specifically, to a frequency optimization method for generating ultrasonic waves, configured to search for a resonant frequency band which fluctuates during an operation process so as to enable ultrasonic waves to be generated under optimal generation conditions, and an ultrasonic wave generating apparatus having a frequency optimization structure. The frequency optimization method for generating ultrasonic waves comprises the steps of: searching for a resonant frequency range with respect to at least one vibrator for generating ultrasonic waves; inputting a test drive signal at predetermined time intervals before or during an operation; detecting an output according to the input of the test drive signal; and determining optimal conditions based on the detected output.

Description

TECHNICAL FIELD [0001] The present invention relates to a frequency optimization method for generating ultrasonic waves and an ultrasonic apparatus using a frequency optimization structure,

The present invention relates to a frequency optimization method for generating ultrasonic waves and to an ultrasonic apparatus with a frequency optimization structure. More specifically, the present invention relates to a frequency optimization method for generating ultrasonic waves in which an ultrasonic wave is generated in an optimal generating condition by searching for a resonance frequency band, And to an ultrasonic device of a frequency-optimized structure.

The ultrasonic device for diagnosis or treatment is composed of a plurality of vibrators, and each of the vibrators can be selected to have the same vibration characteristic. However, the impedance may be varied due to an error occurring in the manufacturing process or an error occurring during the operation, and the resonance may not occur under the predetermined condition. In addition, a change in the load may occur during the operation, and the resonance state may not be maintained. This may reduce the operating efficiency of the ultrasonic device and increase the diagnostic or procedure time. Therefore, there is a need to develop a method that can automatically change the setting to the resonance state according to the change of the operating state or the change of the load.

Patent Registration No. 10-1129129 discloses an automatic resonance frequency control apparatus capable of generating a resonance frequency without depending on a phase-locked loop. Also, Patent Registration No. 10-1411141 discloses a multi-frequency ultrasonic oscillation apparatus having a resonance frequency automatic matching function.

Ultrasonic vibrators having uniform vibration characteristics are substantially difficult to manufacture, and vibrators manufactured in batches may have variations in oscillation frequency, impedance, electro-mechanical vibration conversion coefficient, or similar electro-physical properties. For example, the vibration frequency may have a deviation of 2 to 3% depending on the vibrator, so that the input condition can be appropriately set accordingly. However, in the case of the impedance, a deviation of 10 to 20% is generated in the operation process, which may greatly affect the output characteristics, and the impedance may be changed due to the heat generated in the vibration process, have. Therefore, it is necessary to vary the resonance conditions in accordance with such changes in impedance or other characteristics, and it is therefore necessary to optimize the output efficiency. The prior art does not disclose a method for tracking changes in such resonance conditions and thereby enabling resonant frequency optimization to be obtained.

The present invention has been made to solve the problems of the prior art and has the following purpose.

Prior Art 1: Patent Registration No. 10-1129129 (published by Zero-Won Co., Ltd., March 23, 2012) Automatic control device for resonance frequency of ultrasonic therapeutic apparatus and control method thereof Prior Art 2: Patent Registration No. 10-1411141 (Kim Dongsoo, Announcement of June 23, 2014) Multifrequency ultrasonic oscillation device having resonance frequency automatic matching function

An object of the present invention is to provide a frequency optimization method and a frequency optimization type ultrasonic apparatus for generation of ultrasonic waves in which the ultrasonic waves are generated in the range of optimization of the resonance occurrence by tracking and detecting the resonance fluctuation conditions changed during the operation of the ultrasonic vibrator.

According to a preferred embodiment of the present invention, the frequency optimization method for generating ultrasonic waves and the ultrasonic apparatus of the frequency optimization structure include: searching a resonance frequency range for at least one vibrator for generating ultrasonic waves; Inputting a test drive signal at a predetermined cycle before or during operation; Detecting an output according to an input of the test drive signal; And determining an optimal condition based on the detected output.

According to another preferred embodiment of the present invention, the input of the test drive signal is input in accordance with the impedance change.

According to another preferred embodiment of the present invention, there is provided a pulse width modulation control circuit (PWM); A resonance circuit connected to the pulse width modulation control circuit; An ultrasonic wave generating unit for outputting ultrasonic waves in a frequency band based on the output of the resonance circuit; A condition detecting module for detecting an output of the ultrasonic wave generating unit; A detection unit for detecting a current or voltage of the condition detection module; And a phase comparison circuit for comparing the phase of the detected current or voltage.

According to another preferred embodiment of the present invention, the condition detection module includes a bridge circuit.

The frequency optimization method according to the present invention is applied to a medical ultrasound generator to optimize the resonance condition to generate ultrasonic waves, thereby reducing power consumption and simultaneously reducing the procedure time. Further, the ultrasonic apparatus according to the present invention can be applied to the field of diagnosis or therapy to enable a simple and structurally simple device design.

1 is a block diagram showing an embodiment of a frequency optimization method according to the present invention.
FIG. 2 shows an embodiment of a process of applying the frequency optimization method according to the present invention.
3 shows an embodiment of the ultrasonic device according to the present invention.
FIG. 4 illustrates an operation of an ultrasonic apparatus according to an embodiment of the present invention. Referring to FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings, but the present invention is not limited thereto. In the following description, components having the same reference numerals in different drawings have similar functions, so that they will not be described repeatedly unless necessary for an understanding of the invention, and the known components will be briefly described or omitted. However, It should not be understood as being excluded from the embodiment of Fig.

1 is a block diagram showing an embodiment of a frequency optimization method according to the present invention.

Referring to FIG. 1, a method for optimizing a resonance frequency of an ultrasonic generator includes searching a resonance frequency range for at least one vibrator for generating ultrasonic waves; Inputting a test drive signal at a predetermined cycle before or during operation; Detecting an output according to an input of the test drive signal; And determining an optimal condition based on the detected output.

The ultrasound generator may be but is not limited to a medical ultrasound generator for diagnosis or treatment. The ultrasonic generator may comprise at least one oscillator, and each oscillator may have an operating range of 53.35 to 56.65 kHz, for example with an error of +/- 3% around 55 kHz. The resonance frequency of each oscillator is determined by the inductance and the capacitance, and the output of the oscillator can be determined by the impedance. The inductance and capacitance can be determined by the coils and capacitors installed in the ultrasonic device, and the impedance can be determined by resistance, inductance and capacitance, and can vary with frequency.

The condition setting unit 11 may have a function of determining parameters affecting the resonance frequency and the output in the ultrasonic apparatus. For example, the condition setting unit can be used to determine the effect of other elements on the inductance and capacitance of the coil and the capacitor in different frequency bands, the change in resistance (R) at different temperatures, The conditions under which data can be generated can be set. For this purpose, the condition setting unit 11 can set parameters affecting the resonance frequency and the reactance. When the parameters affecting the resonance frequency and the reactance are determined by the condition setting unit 11 in this way, the resonance frequency can be searched. The resonance frequency search unit 12 may have a function of searching for a resonance frequency and a maximum output while changing a parameter value set by the condition setting unit 11. [ When a plurality of vibrators are disposed in the ultrasonic device, the resonance frequency and the maximum output may be detected for each vibrator, or the resonance frequency and the maximum output may be detected for the plurality of vibrators. The maximum output is obtained at the resonance frequency, but the impedance change may occur in the range of 10 to 20% depending on the change of the temperature during the operation, for example, so that the resonance state may not be maintained according to the temperature rise. Also, the temperature rise can be limited to a predetermined range. The resonance frequency search unit 12 determines the conditions under which the maximum output is maintained at the resonance frequency, the maintenance of the resonance state according to the parameters that affect the impedance such as the temperature change, or the maintenance of the gap between the resonance frequency and the maximum output It can have a function of searching for an allowable range. In order to search for such a resonance frequency, a test drive signal may be generated from the drive signal unit 14 and transmitted to the vibrator. The test drive signal may be determined in accordance with the manufacturing specification, for example, assuming that the resonance frequency is 55 kHz. Specifically, a driving signal can be generated and applied in units of 100 to 300 Hz in a range of 53 kHz to 57 kHz based on 55 kHz corresponding to the resonance frequency. And the variable detection unit 13 can detect the output in different frequency bands. The test drive signal can be applied under different conditions, and can be applied, for example, to the vibrator for different temperature conditions or for different loads. And resonance conditions can be detected for different parameters. The resonance conditions include, for example, a frequency at which the impedance becomes minimum, a frequency at which the current and voltage become equal in phase, or a frequency at which the current becomes the maximum. And such resonance conditions can be detected at different loads or at different temperatures. The variable detection unit 13 can transmit the detection result to the optimum condition determination unit 15. [ The optimum condition determining unit 15 can determine the resonance condition for different parameter values while at the same time determining the condition change band. The condition change band is detected as being out of the resonance frequency based on, for example, the current detected in the variable detection unit 13, the phase difference or the output value, and even if adjusting the impedance, frequency or temperature in the ultrasonic device, Or a range in which the effect due to a change in the generated output is not large. Such a condition change band can be determined by the application field of the ultrasonic device or the application target of the ultrasonic device or the specifications of the ultrasonic device. The optimum condition determining unit 15 can determine the resonance frequency and the condition change band for different variables. Further, the drive signal unit 14 can determine the range in which the test drive signal is generated so that such a condition change band can be determined. For example, the test drive signal is applied while changing to a magnitude of 100 Hz, but can be applied while changing to a magnitude of 10 to 20 Hz in a range adjacent to the resonance frequency. For example, the condition change band can be determined as ± 1 to 3% with respect to the virtual maximum output. When the optimum condition is determined in this way, the optimum condition data is generated accordingly, and the optimum condition data can be transmitted to the condition setting unit 11. [ The ultrasonic apparatus can be operated according to the conditions determined by the condition setting unit 11. [ And, if the condition change band set in the optimum condition data is deviated, the operating condition can be changed accordingly. Changes in operating conditions may include, for example, frequency adjustment, capacitor adjustment, inductance adjustment, temperature adjustment or resistance adjustment.

The operation of the ultrasonic device thus operated will be described below.

FIG. 2 shows an embodiment of a process of applying the frequency optimization method according to the present invention.

Referring to FIG. 2, a method for optimizing a frequency of an ultrasonic apparatus includes a step (P21) of setting a range of a resonance frequency for at least one vibrator; Determining a band frequency in a range of the set resonance frequency and applying the frequency while varying the frequency within a range of the resonance frequency (P22); Determining (P23) a resonance frequency for at least one oscillator while the band frequency is applied; Setting a detection parameter (P24) that affects the resonance condition; Setting a correlation between the parameter and the fluctuation of the resonance frequency or the fluctuation of the maximum output (P25); Detecting an output while operating the ultrasonic device (P26); And determining whether the variation range of the detected output is within a predetermined range (P27).

As described above, the vibrator is designed and manufactured to be resonant in a specific frequency band, but the vibration frequency may change in a manufacturing process or in an installed state in an ultrasonic device. Setting the resonance frequency range means setting a certain interval on the assumption that an error occurs based on the resonance frequency indicated in the manufacturing specification of the resonator (P21). For example, the resonance frequency range may be set in a range of 2 to 5% of the display resonance frequency.

When the resonance frequency range is set (P21), the output or resonance can be detected while the band frequency is applied in the range of the resonance frequency (P22). The band frequency may be in the range of, for example, 50 to 250 Hz, and may be applied while increasing the band frequency range from a small value of the set resonance frequency range. The value of the band frequency may be set to a relatively small value in order to determine the condition change band in the portion where the resonance occurs. If the resonance frequency is determined by the application of the band frequency range, a detection parameter that affects the resonance frequency or the maximum output can be set (P24). The detection parameter may be, for example, the temperature, the load, or the impedance matching level of the load. Correlation refers to the influence of such parameters on the change of the impedance and the variation of the output with the change of the impedance. The impedance change or the output change with respect to the variation of the parameter may be displayed in intervals or displayed in a graph, and a condition variation band according to the variation may be set in each parameter or a plurality of parameters (P25). When the resonance frequency is determined in this manner (P23) and the parameter correlation according to the resonance frequency is determined (P25), the ultrasonic device can be operated based on it. And the output of the ultrasonic device may be detected (P26).

The operating environment of the ultrasonic apparatus may be changed during the operation of the ultrasonic apparatus, and the impedance of the ultrasonic apparatus may be changed. For example, heat may be generated due to the operation of the vibrator or the generation of ultrasonic waves. As the heat is generated, the impedance changes and the resonance condition or the maximum output condition may change. The change range of the impedance or the level of change in output relative to the maximum output can be determined (P27). If the change range of the impedance or the change of the output is out of the predetermined range (NO), the detection parameter may be reset (P24) and the resonance condition may be searched again in the current operation state (P24). For example, the operation of the part or element associated with the parameter can be adjusted based on the set parameter. Specifically, the input frequency may be adjusted, the cooling means may be operated to adjust the temperature, or the reactance or capacitance may be adjusted. On the other hand, if the change range of the impedance or the change in the output is within the predetermined range or the range of the condition change band, the output can be continuously detected (P26).

The method of optimizing the ultrasonic device in the present invention can be performed by various methods, and is not limited to the embodiments shown.

3 shows an embodiment of the ultrasonic device according to the present invention.

3, the ultrasonic device 30 includes a pulse width modulation control circuit (PWM) 32; A resonant circuit 34 connected to the pulse width modulation control circuit 32; An ultrasonic wave generating unit (35) for outputting an ultrasonic wave in a frequency band based on the output of the resonance circuit (34); A condition detecting module 36 for detecting the output of the ultrasonic wave generating unit 35; Detection units (371, 327) for detecting the current or voltage of the condition detection module (36); And a phase comparison circuit 38 for comparing the phase of the detected current or voltage.

An ultrasonic generation signal generated by a vibration generator 31 such as a voltage control oscillator VCO is controlled by a pulse width modulation control circuit 32 so that duty cycle and frequency are adjusted and transmitted to a transformer 33, The voltage can be adjusted. In a state where the input voltage is adjusted, the ultrasonic generation signal may be input to the resonance circuit 34 and resonated. The resonance circuit 34 may be a series resonance circuit or a parallel resonance circuit, and a switching circuit may be provided in the pulse width modulation control circuit (PWM) 32 to allow the resonance circuit 34 to open and close the input of the ultrasonic generation signal have. The power source may be disposed inside or outside the resonance circuit 34 according to the configuration of a circuit such as a series resonance circuit or a parallel resonance circuit, and the power supply may be performed by, for example, a HVDC (High Voltage Direct Current) method. Then, the vibration generated in the resonance circuit 34 is transmitted to the ultrasonic wave generating unit 35 to generate vibration. The ultrasonic wave generating unit 35 may include at least one oscillator 351. The oscillator 351 may convert an electric oscillation to a mechanical oscillation to generate ultrasonic waves, But can be adjusted to the appropriate waveform.

The operating state may change during the operation of the ultrasonic apparatus, and thus the resonance condition or the maximum output condition may be changed, and such a change in the resonance condition may be detected by the condition detection module 36. [ The condition detection module 36 may have the function of detecting whether the ultrasonic device is operating in the resonance state, for example, detecting the range where the value of the reactance becomes minimum. Or the maximum current or minimum current in the resonance state in the direct current resonance circuit or the parallel resonance circuit can be compared with the operating current in the operating state. The condition detection module 36 can detect the operating state of the ultrasonic device 30 in various ways, and is not limited to the illustrated embodiment.

A voltage detection circuit may be arranged in parallel with the vibrator 351 to detect the resonance state so that the voltage can be detected by the voltage detection unit 372. [ Further, a current flowing from the condition detecting module 36 through the ultrasonic wave generating unit 35 can be detected. For example, the condition detection module 36 may include a comparison detection unit 361 connected in series with the ultrasonic generating unit and a comparison detection unit 362 for detecting a change in the detected current in the comparison detection unit 361 . And the detected current change in the comparison detection unit 362 can be transmitted to the current detection unit 371. [ The current and voltage detected by the current detection unit 371 and the voltage detection unit 372 may be transmitted to the phase comparison circuit 38. [ The comparison detection unit 362 may be a detection circuit such as, for example, a Wheatstone bridge.

It is possible to determine whether the ultrasonic device 30 is in the resonance state by comparing the phases of the current and the voltage in the phase comparison circuit 38. The reactance can also be calculated and a level deviating from the resonance state can be determined. The phase comparison circuit 38 can determine whether the operating state of the ultrasonic device 30 also corresponds to the condition change band or not and transmit the determination result to the vibration generator 31. [ The vibration generator 31 can change the conditions of the ultrasonic wave generation in accordance with the comparison result transmitted from the phase comparison circuit 38. [

The ultrasonic device 30 may include various detection modules for searching for resonance conditions and is not limited to the embodiments shown.

FIG. 4 illustrates an operation of an ultrasonic apparatus according to an embodiment of the present invention. Referring to FIG.

4, a control unit 41 for controlling the entire operation of the ultrasonic apparatus can be provided, and the overall operation of the ultrasonic apparatus can be controlled by the control unit 41. [ The control unit 41 can control the operation of the vibration generator 31 described above, for example. When the operation setting unit 42 is operated by the control unit 41, the operation setting unit 42 sets the vibrator 351 on the basis of the resonance data transmitted from the control unit 41 while storing the operating condition of the ultrasonic apparatus So that ultrasonic waves having predetermined output characteristics can be generated. In order to detect the vibration characteristic of the vibrator 351, the detection setting unit 43 can set a method for detecting the known frequency of the vibrator. The detection setting unit 43 may store the vibration characteristics of the vibrator and set a method for detecting the resonance characteristics as described above. For example, the detection setting unit 43 can determine the resonance search frequency range and determine the search frequency range based on the displayed resonance frequency. As described above, when the resonance frequency is indicated as 55 kHz, the resonance search frequency range can be set to 53 kHz to 57 kHz, and the search frequency range can be set to 50 to 200 Hz. The driving signal can be applied to the oscillator 351 by the operation of the input switch 45 while being increased from 53 kHz to 50 to 200 Hz by the test drive signal generating unit 44. [ And whether or not the resonance condition is detected by the condition detection module 36 can be detected. The detection results can be sent to the comparator 46, which can detect the output reduction range at different frequencies that deviate from the resonant frequency and resonant frequency. The comparator 46 may also determine the condition reversible band described above and transmit it to the resonance condition data unit 47. [ The resonance condition data unit 47 can generate resonance data that determines the optimum operating level of the ultrasonic device and the control unit 41 can operate the ultrasonic device based on the resonance data.

The detection setting unit 43 can be operated for searching for the resonant frequency in the operation process of the ultrasonic apparatus. For example, the result detected by the condition detection module 36 may be transmitted to the comparator 46, and the comparator 46 may transmit it to the control unit 41 if it is determined that the current operation level belongs to the conditional reversible band have. Then, the control unit 41 can operate the test drive signal generating unit 44 by setting a condition for searching the resonance frequency in the detection setting unit 43. [ Then, through the above-described procedure, the resonance frequency is searched in the operating state, and new resonance data can be generated. Then, the control unit 41 is operated in accordance with the generated resonance data so that the operation of the ultrasonic device can be adjusted.

The ultrasonic device can be operated in various ways and is not limited by the embodiments shown. The frequency optimization method according to the present invention is applied to a medical ultrasound generator to optimize the resonance condition to generate ultrasonic waves, thereby reducing power consumption and simultaneously reducing the procedure time. Further, the ultrasonic apparatus according to the present invention can be applied to the field of diagnosis or therapy to enable a simple and structurally simple device design.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention . The invention is not limited by these variations and modifications, but is limited only by the claims appended hereto.

11: Condition setting unit 12: Resonance frequency search unit
13: Variable detection unit 14: Drive signal unit
15: Optimum condition determining unit 30: Ultrasonic device
31: Vibration generator 32: Pulse width modulation control circuit
33: transformer 34: resonant circuit
35: ultrasonic wave generating unit 36: condition detecting module
38: phase comparison circuit 41: control unit
42: Operation setting unit 43: Detection setting unit
44: test drive signal generating unit 45: input switch
46: comparator 47: resonance condition data unit
351: Oscillator 361: Comparison detection unit
362: comparison detection unit 371: current detection unit
372: Voltage detection unit

Claims (4)

A method of optimizing a resonance frequency of an ultrasonic generator,
Searching for a resonant frequency range for at least one vibrator for generating ultrasonic waves;
Inputting a test drive signal at a predetermined cycle before or during operation;
Detecting an output according to an input of the test drive signal; And
And determining an optimal condition based on the detected output. The method of claim 1, wherein the input of the test drive signal is input according to an impedance change. A pulse width modulation control circuit (PWM) 32;
A resonant circuit 34 connected to the pulse width modulation control circuit 32;
An ultrasonic wave generating unit (35) for outputting an ultrasonic wave in a frequency band based on the output of the resonance circuit (34);
A condition detecting module 36 for detecting the output of the ultrasonic wave generating unit 35;
Detection units (371, 327) for detecting the current or voltage of the condition detection module (36); And
And a phase comparison circuit (38) for comparing the phase of the detected current or voltage. The ultrasound system of claim 1, wherein the condition detection module (36) comprises a bridge circuit.

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