Portable LIPUS ultrasonic pulse therapeutic apparatus

Abstract

The utility model relates to a portable LIPUS ultrasonic pulse therapeutic apparatus. The therapeutic apparatus comprises a shell, a unit circuit in the shell, a touch panel on the shell, a voltage sampling circuit interface located at one end of the shell and a plurality of ultrasonic probe interfaces located at the other end of the shell. Wherein the touch panel, the voltage sampling circuit interface and the ultrasonic probe interface are electrically connected with the unit circuit respectively. The LIPUS therapeutic apparatus has the advantages that by establishing the LIPUS energy conversion model and by means of the high-frequency electronic technology and the embedded software technology, multi-parameter adjustment of the frequency, the sound intensity and the pulse mode of the LIPUS therapeutic apparatus can be achieved, support is provided for clinical medical tests of LIPUS treatment, proper LIPUS treatment parameters can be selected for different symptoms, and the LIPUS therapeutic apparatus can be used for treating different symptoms. The method has important theoretical research and medical application values.

Description

Technical Field

[0001] The utility model relates to the technical field of ultrasonic medical treatment, in particular to a portable LIPUS ultrasonic pulse therapeutic apparatus. Background Art

[0002] LIPUS ultrasonic treatment method has a good therapeutic effect on symptoms that are difficult to heal by themselves, such as fractures and cartilage injuries, but how to find the appropriate LIPUS "therapeutic dose" for different symptoms is a problem that is of great concern in clinical medicine.

[0003] The so-called LIPUS "treatment dose" refers to four key parameters: ultrasonic center frequency, sound intensity, pulse mode and treatment time. The difficulty in designing a multi-parameter adjustable LIPUS therapeutic device lies in:

[0004] 1. Precise control of mW-level ultrasonic energy.

[0005] 2. On the same PCB printed circuit board, ultrasonic signals of multiple frequencies and multiple gears are generated, and mutual coupling and interference will occur between the amplifying unit circuits.

[0006] At the same time, the adjustable parameters provided by the LIPUS therapeutic device are very limited. How to screen out appropriate LIPUS frequency, sound intensity and pulse mode treatment plans for different symptoms in clinical treatment is a problem that the industry urgently needs to solve.

[0007] In view of the above problems, this utility model proposes a LIPUS therapeutic instrument architecture with adjustable frequency, sound intensity and pulse mode parameters by establishing a LIPUS energy conversion model, using high-frequency electronic technology and embedded software technology, and provides a design method for key unit circuits. It is expected to provide support for clinical medical trials of LIPUS treatment and help select appropriate LIPUS treatment parameters for different symptoms, which has important theoretical research and medical application value. Utility Model Content

[0008] The purpose of the utility model is to solve the above problems, and a portable LIPUS ultrasonic pulse therapeutic apparatus is provided for this purpose.

[0009] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0010] A portable LIPUS ultrasonic pulse therapeutic device, comprising a shell, a unit circuit in the shell, a touch panel on the shell, a voltage sampling circuit interface at one end of the shell, and a plurality of ultrasonic probe interfaces at the other end of the shell; wherein the touch panel, the voltage sampling circuit interface, and the ultrasonic probe interface are electrically connected to the unit circuit respectively.

[0011] The portable LIPUS ultrasonic pulse therapeutic device provided by the utility model may also have the following technical features: the unit circuit includes a microcontroller unit, a signal generator unit, a programmable amplifier unit, a PA power amplifier unit and a piezoelectric transducer unit; wherein the microcontroller unit adopts PWM technology to control the modulation signal frequency and pulse width by outputting a pulse square wave to obtain output signals with different duty cycles through voltage, and the microprocessor is connected to the voltage sampling circuit through the A / D conversion interface to monitor the output signal voltage change and start the alarm circuit and cut off the output signal when the ultrasonic probe is unloaded; in addition, the microcontroller unit also controls the data operation output and input of the signal generator unit, the programmable amplifier unit, the PA power amplifier unit and the piezoelectric transducer unit.

[0012] The portable LIPUS ultrasonic pulse therapeutic device provided by the utility model may also have the following technical features: the signal generator unit adopts DDS chip direct digital frequency synthesis technology, and is a high-frequency sine wave signal generator that can controllably output stable ultrasonic pulses of 1.0MHz, 1.5MHz, 2.0MHz, 2.5MHz and 3.0MHz at 5 different frequencies; wherein the ultrasonic pulses at each frequency point include 7 levels of sound intensity.

[0013] The portable LIPUS ultrasonic pulse therapeutic apparatus provided by the utility model may also have the following technical features: the signal generator unit is a high-frequency sine wave signal generator with a pulse duty cycle of 20%-50% which is continuously adjustable.

[0014] The portable LIPUS ultrasonic pulse therapeutic apparatus provided by the utility model may also have the following technical features: the program-controlled amplifier unit is used to perform program-controlled amplification on the generated high-frequency sine wave signal, and the amplification factor of the program-controlled amplifier unit is 2 times or 3 times.

[0015] The portable LIPUS ultrasonic pulse therapeutic apparatus provided by the utility model may also have the following technical features: the PA power amplifier unit includes a push-pull power amplifier circuit without an output transformer.

[0016] The portable LIPUS ultrasonic pulse therapeutic device provided by the utility model may also have the following technical features: the piezoelectric transducer unit adopts the inverse piezoelectric effect of the piezoelectric ceramic sheet to convert the input high-frequency sinusoidal wave pulse signal into sinusoidal pulse ultrasonic energy for output; wherein each frequency gear adopts a piezoelectric transducer with an effect resonant frequency; correspondingly, an impedance matching circuit unit matching the piezoelectric transducer unit is also connected to the piezoelectric transducer unit.

[0017] The portable LIPUS ultrasonic pulse therapeutic device provided by the utility model may also have the following technical features: the static capacitance of the piezoelectric transducer unit is Cp, and an inductor L is connected in parallel at both ends of the piezoelectric transducer unit to form an LC parallel resonant network; wherein, by tuning the static capacitance Cp to the resonant frequency fo of the piezoelectric transducer unit, the conversion from a capacitive load to a pure resistive load can be realized, and the load resistance value after the conversion is Rp;

[0018] The LC parallel resonant frequency formula is as follows:

[0019]

[0020] Since the unit of parallel inductance value is mostly uH level, in order to facilitate calculation, the LC parallel resonant frequency formula is transformed into:

[0021]

[0022] Wherein, Cp represents the static capacitance, fo represents the static capacitance Cp is tuned at the resonant frequency of the piezoelectric transducer unit.

[0023] The portable LIPUS ultrasonic pulse therapeutic device provided by the utility model may also have the following technical features: the touch panel is an OLED liquid crystal touch display, and parameter adjustment and display of status marks on the therapeutic device can be completed by touching the touch panel.

[0024] The utility model has the advantages that:

[0025] The utility model establishes a LIPUS energy conversion model and, with the help of high-frequency electronic technology and embedded software technology, can achieve multi-parameter adjustment of the frequency, sound intensity and pulse mode of the LIPUS therapeutic instrument, provide support for clinical medical trials of LIPUS treatment, and help select appropriate LIPUS treatment parameters for different symptoms, which has important theoretical research and medical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the portable LIPUS ultrasonic pulse therapeutic device described in the embodiment of the utility model.

[0027] Figure 2 It is a system architecture diagram of the portable LIPUS ultrasonic pulse therapeutic device described in the embodiment of the utility model.

[0028] Figure 3 It is the ultrasonic energy conversion model in the LIPUS ultrasonic pulse therapeutic device in the embodiment of the utility model.

[0029] Figure 4It is a programmable control block diagram of a high-frequency sinusoidal ultrasonic pulse signal in an embodiment of the utility model.

[0030] Figure 5 It is an OTL power amplifier circuit of a high-frequency sinusoidal ultrasonic pulse signal in an embodiment of the utility model.

[0031] Figure 6 It is a no-load protection block diagram in an embodiment of the utility model.

[0032] Figure 7 It is a multi-frequency channel switching circuit model of the LIPUS ultrasonic pulse therapeutic instrument in the embodiment of the utility model.

[0033] Figure 8 It is a control program flow chart of the LIPUS ultrasonic pulse therapeutic apparatus in an embodiment of the utility model.

[0034] Fig. 9 It is a performance index test block diagram of the LIPUS ultrasonic pulse therapeutic apparatus in an embodiment of the utility model.

[0035] The reference numerals and components involved in the drawings are as follows:

[0036] 1. Shell;

[0037] 2. Unit circuit; 21. Microcontroller unit; 22. Signal generator unit;

[0038] 23. Program-controlled amplifier unit; 24. PA power amplifier unit; 25. Piezoelectric transducer unit;

[0039] 3. Touch panel; 4. Voltage sampling circuit interface; 5. Ultrasonic probe interface; 6. DDS chip;

[0040] 7. Impedance matching circuit unit. DETAILED DESCRIPTION

[0041] The present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the contents recorded in the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

[0042] like Figure 1 , Figure 2 As shown, the utility model mainly includes a housing 1, a unit circuit 2 in the housing, a touch panel 3 on the housing, a voltage sampling circuit interface 4 located at one end of the housing, and a plurality of ultrasonic probe interfaces 5 located at the other end of the housing;

[0043] The touch panel 3 , the voltage sampling circuit interface 4 , and the ultrasonic probe interface 5 are electrically connected to the unit circuit 2 , respectively.

[0044] In this embodiment, the unit circuit 2 includes a microcontroller unit 21, a signal generator unit 22, a programmable amplifier unit 23, a PA power amplifier unit 24 and a piezoelectric transducer unit 25; wherein the microcontroller unit 21 adopts an STM32MCU microcontroller, and controls the data operation output and input of the signal generator unit 22, the programmable amplifier unit 23, the PA power amplifier unit 24 and the piezoelectric transducer unit 25.

[0045] Correspondingly, the microcontroller unit 21 adopts PWM technology to control the modulation signal frequency and pulse width by outputting pulse square waves to obtain modulated sinusoidal wave signals with different duty cycles; the microcontroller unit 21 obtains output signals of different intensities by controlling the voltage amplification and power amplifier output circuit; the voltage sampling circuit is connected through the A / D conversion interface to monitor the output signal voltage change and start the alarm circuit and cut off the output signal when the ultrasonic probe is unloaded.

[0046] In addition, the signal generator unit 22 in the utility model adopts the direct digital frequency synthesis technology of the DDS chip 6, and can control the output of stable high-frequency sine wave signals of 1.0MHz, 1.5MHz, 2.0MHz, 2.5MHz and 3.0MHz. Compared with the traditional transformer positive feedback high-frequency oscillation circuit, the DDS chip can be controlled by software, which is convenient for modifying the output frequency of the LIPUS therapeutic instrument, and the output high-frequency sine wave oscillation signal is more stable. In addition, considering that the output impedance of the DDS chip is large and the load capacity is weak, a voltage follower can be added to the next stage, so that the input signal of the signal source can be truly transmitted to the next stage.

[0047] Among them, under the action of the 32-bit MCU microcontroller unit 21, it outputs a PWM signal (pulse width modulation) with a repetition frequency of 1kHz and a corresponding duty cycle of 20%, 25%, 33%, and 50%. Its PWM signal input is an ADG821 analog switch chip, and is multiplied with the high-frequency sine wave signal output by the DDS chip to achieve ASK modulation, thereby generating a high-frequency sine wave pulse signal.

[0048] Correspondingly, the programmable amplifier unit 23 uses a two-stage operational amplifier to programmably amplify the generated high-frequency sine wave signal to meet the requirements of the high-frequency power amplifier (PA) unit circuit for the input voltage amplitude. At the same time, considering the relationship between the bandwidth and gain of the high-frequency programmable amplifier unit, the amplification factors designed by the utility model are 2 and 3 respectively.

[0049] Meanwhile, in order to reduce high-frequency noise in the present utility model, a PA power amplifier unit 24 is adopted in this design. The PA power amplifier unit 24 includes a push-pull power amplification circuit without an output transformer. Its output power is related to the amplitude and amplification factor of the input signal. Among them, the amplitude and amplification factor of the input signal are composed of multiple potentiometers and an analog multiplexer chip; and the 32-bit MCU microcontroller selects the amplification factor of the driving stage through software, and finally realizes the output of sound intensity signals at 7 levels for each frequency point.

[0050] Correspondingly, the piezoelectric transducer unit 25 in the present utility model uses the inverse piezoelectric effect of piezoelectric ceramic sheets to convert the input high-frequency sine wave pulse signal into sine pulse ultrasonic energy for output. Among them, an impedance matching circuit unit 7 that matches it is also connected to the piezoelectric transducer unit 25. In order to improve the energy conversion efficiency, the following measures are also adopted:

[0051] (1) The piezoelectric transducer unit of the effect resonance frequency is adopted for each frequency level.

[0052] (2) Considering that the piezoelectric transducer unit 25 is a capacitive load, it is converted into a pure resistive load through an LC parallel resonance impedance transformation circuit, and at the same time plays the role of a band-pass filter.

[0053] As Figure 3 shown, the high-frequency sine wave pulse signal V amplified by the programmable amplifier unit 23 is input to the high-frequency power amplifier unit, and Pa is the output power of the high-frequency power amplifier unit. The static capacitance of the piezoelectric transducer unit 25 is Cp, and a suitable inductor L is connected in parallel at both ends of it (this process is called impedance transformation), and it can be equivalent to a pure resistor Rp. Through impedance transformation, on the one hand, it can improve the effective output power Po of the piezoelectric transducer, and on the other hand, it can also use the higher quality factor of the LC parallel network to filter out noise interference. s Among them, the piezoelectric transducer unit 25 working in the resonance state can emit pulsed ultrasonic waves by contacting the human tissue through a coupling agent. Let the pulsed ultrasonic wave sound power emitted be Po. Obviously Po < Pa, denoted as:

[0054] Po / Pa = K (1)

[0055]

[0056] Then K is the electromechanical coupling coefficient of the piezoelectric transducer unit 25, and generally K = 0.55 is taken. Its physical meaning is that about 55% of the electrical energy output by the power amplification circuit is converted into ultrasonic energy emitted by the ultrasonic transducer into the human tissue. Thus, the mathematical expression of the output sound intensity Is of the piezoelectric transducer can be further deduced: Is = Po / Ae (2)

[0057]

[0058] ​Wherein, Ae is the effective radiating area of ​​the ultrasonic transducer. In the present invention, the diameter of the piezoelectric transducer unit is 2 cm, and the geometric area is 3.14 cm 2 , effective radiation area is 2.5cm 2 .

[0059] According to formulas (1) and (2), the corresponding relationship between the output sound intensity Is level of the LIPUS therapeutic device and the output power Pa of the power amplifier unit can be calculated. Taking the provisional level 7 as an example, the calculation results are shown in Table 1 below.

[0060] Table 1 Correspondence between the output sound intensity Is of the LIPUS therapeutic device and the output power Pa of the power amplifier circuit. (Take the effective radiation area A of the ultrasonic transducer ER =2.50cm 2 ; Electromechanical coupling coefficient k = 0.55)

[0061] Gear 1 2 3 4 5 6 7 <![CDATA[Is(mW / cm 2 )]]> 30.00 45.00 60.00 90.00 120.00 150.00 180.00 Po(mW) 75.00 112.50 150.00 225.00 300.00 375.00 450.00 Pa(mW) 136.36 204.55 272.73 409.09 545.45 681.82 818.18

[0062] It should be noted that when the number of gears and the output sound intensities corresponding to the gears change, the calculation method remains unchanged.

[0063] In addition, in the present invention, the piezoelectric transducer unit 25 is a piezoelectric ultrasonic transducer based on the piezoelectric effect. Compared with other types of ultrasonic transducers such as magnetostrictive transducers, it has the advantages of low electromagnetic radiation and high energy conversion efficiency, and is more suitable for application in the field of ultrasonic medical treatment. In addition, from the perspective of electrical engineering, the piezoelectric ultrasonic transducer is a typical capacitive load: as the frequency increases, its reactance decreases, and the available effective output power decreases. In order to eliminate the static capacitance C P In order to reduce the influence of the piezoelectric transducer unit and improve the energy conversion efficiency, the utility model also connects an inductor L in parallel at both ends of the piezoelectric transducer unit to form an LC parallel resonant network (LC parallel resonant circuit is a commonly used unit circuit in communication electronic circuits, and under the signal excitation of different operating frequencies, the LC parallel resonant circuit exhibits different impedance amplitude-frequency characteristics and phase-frequency characteristics. In communication electronic circuits, it is a unit circuit with very flexible application. In amplifiers, mixers, sine wave oscillators, modulation and demodulation and other functional circuits, the LC parallel resonant circuit plays different roles)), see for details. Figure 3 .

[0064] Wherein, Cp is the static capacitance of the piezoelectric transducer unit 25; and by tuning it at the resonant frequency fo of the piezoelectric transducer unit 25, the conversion from capacitive load to pure resistive load can be realized, and the load resistance value after conversion is Rp. Specifically, the LC parallel resonant frequency formula is as follows:

[0065]

[0066] Considering that the parallel inductance is mostly in uH level (microhenry), for the convenience of calculation, formula (3) can be slightly transformed:

[0067]

[0068] According to clinical medical knowledge, ultrasonic pulses of different frequencies are suitable for different symptoms. The LIPUS therapeutic device designed by the utility model can output ultrasonic pulses of 5 different frequencies: 1.0MHz, 1.5MHz, 2.0MHz, 2.5MHz and 3.0MHz. Each of its ultrasonic pulses of different frequencies contains 7 levels of sound intensity, as shown in Table 1 above. However, in terms of 5 different frequencies, 5 piezoelectric ultrasonic probes need to be connected to the LIPUS therapeutic device, and the resonant frequencies of these 5 ultrasonic probes are 1.0MHz, 1.5MHz, 2.0MHz, 2.5MHz and 3.0MHz respectively.

[0069] As mentioned above, "the piezoelectric ultrasonic transducer is a typical capacitive load: as the frequency increases, its reactance decreases and the available effective output power decreases." Therefore, in order to convert it into a pure resistive load and reduce noise interference, the required parallel inductance L value (unit: uH) can be calculated according to formula (4). The calculation results are shown in Table 2 below.

[0070] Table 2. Piezoelectric ultrasonic transducer parameters and inductance values ​​required for impedance transformation

[0071]

[0072] It should be noted that: 1. It is difficult to make the static capacitance Cp of piezoelectric transducers of the same resonance point and different batches consistent, and there may even be large deviations. The inductance value calculated by formula (4) will inevitably have obvious deviations. 2. At the same time, unlike resistance and capacitance, inductance L has no nominal value, that is, the inductance L value calculated according to formula (4) is likely to be unavailable for use.

[0073] In the development of LIPUS therapeutic device, in order to better solve the above two problems, we adopted the following methods: 1. Use several sets of commonly used inductance values ​​for series and parallel connection to obtain the approximate value of L. 2. In terms of hardware circuit design, several sets of alloy chip power inductors with different inductance values ​​are used for series and parallel connection. On the one hand, this type of inductor has stronger anti-interference ability and can isolate mutual inductance, which is convenient for circuit design; on the other hand, the entire impedance conversion unit circuit adopts modular design: the geometric dimensions and electrical interfaces are consistent, and it can be easily inserted into the motherboard PCB.

[0074] like Figure 4As shown, in this embodiment, the functions of the high-frequency sinusoidal wave pulse oscillator (LC high-frequency sinusoidal wave oscillator is an oscillator that uses L and C components to form a frequency selection network, generally used to generate a high-frequency sinusoidal signal above 1MHz; it corresponds to the LC parallel resonant network loop mentioned above) are: (1) to generate high-frequency sinusoidal wave pulse voltage signals required by multiple frequency points and multiple modes (duty cycles) of the LIPUS therapeutic device. (2) The high-frequency sinusoidal wave pulse voltage signal requires a certain amplitude to meet the requirements of the power amplifier stage circuit for the input signal amplitude. As far as the utility model is concerned, it is necessary to generate five kinds of sinusoidal wave pulses, namely 1.0MHz, 1.5MHz, 2.0MHz, 2.5MHz and 3.0MHz; each sinusoidal wave pulse has four duty cycles: 1:1, 1:2, 1:3, 1:4; a total of 20 waveforms. If the traditional design method of "pure hardware" of high-frequency electronic circuits is adopted, it is difficult to generate high-frequency voltage signals with 20 different waveforms on a PCB circuit board. To this end, we adopted the method of DDS direct frequency synthesizer chip, which can be programmed and controlled by MCU single chip, that is, the register of DDS chip is controlled by embedded software to generate 20 different sine wave pulse voltage signals. This provides convenient conditions for the adjustment and expansion of LIPUS therapeutic instrument frequency and pulse mode.

[0075] At the same time, two details need to be considered: 1. The peak-to-peak value of the high-frequency sinusoidal pulse signal output by the DDS chip 6 is only 0.6V, which cannot meet the input voltage requirements of the power amplifier circuit. It needs to be program-controlled amplified before connecting to the next-level power amplifier circuit. For the convenience of circuit debugging, we use a 2-level program-controlled amplification mode. 2. As a signal source, the DDS chip has a large output impedance. For this reason, we can connect a voltage follower in series at the output end of the DDS chip 6 to reduce the output impedance of the signal source.

[0076] like Figure 5 As shown, only after the high-frequency sinusoidal wave pulse signal is properly amplified can it be connected to the piezoelectric transducer unit 25 after impedance transformation to realize the ultrasonic pulse emission function required by each frequency point and each gear of the LIPUS therapeutic device. There are four main types of high-frequency sinusoidal wave power amplifier circuits: OTL circuit, OCL circuit, Class D power amplifier circuit and Class E power amplifier circuit. In comparison, the OTL circuit is powered by a single power supply, the circuit structure is simple, and the energy conversion efficiency meets the power requirements of the LIPUS therapeutic device. Therefore, this design uses the OTL circuit as the power amplifier unit (such as Figure 5 It is the OTL power amplifier circuit in the utility model).

[0077] Among them, the power tube Q1 constitutes the driving stage; Q2 and Q4, Q3 and Q5 are a pair of NPN and PNP type crystal transistors with symmetrical parameters, forming a complementary push-pull OTL power amplifier circuit; R10, R11, R12 and R13, R14 respectively constitute a local current negative feedback circuit, so that the collector current of the transistor will not increase with the increase of temperature, protecting it from being burned by large current; potentiometer REG_50k is a negative feedback resistor to improve the stability of the output voltage; capacitors C18, R7, R9 form a bootstrap circuit to increase the upper limit of the output voltage; capacitor C21 with a small impedance in parallel at the output end can filter out high-frequency noise.

[0078] Since the impedance value of the piezoelectric transducer unit 25 after impedance transformation is still small, a sufficiently large output current is required to meet the expected output power. Therefore, the utility model can use a diode and a potentiometer to form a series circuit to provide a bias voltage to the push-pull tube, so that the output current is large enough.

[0079] At the same time, in the present invention, the generation of high-frequency sinusoidal pulse signals, the precise control of the output sound intensity of high-frequency sinusoidal pulse ultrasonic signals, and the impedance transformation method of ultrasonic transducers are the technical cores of the multi-parameter LIPUS therapeutic instrument. In addition, the no-load protection of the therapeutic instrument, the channel switching method between multiple frequency points, and the control software are also very important functions; their specific implementation is as follows:

[0080] like Figure 6 As shown, when the piezoelectric transducer unit 25 is not in contact with the patient's skin or the coupling agent is insufficient, the ultrasonic wave emitted by the piezoelectric transducer unit 25 will not be fully released, and due to the positive piezoelectric effect, the transducer will generate a backflow current, causing the LIPUS therapeutic instrument circuit to be damaged due to overheating. Therefore, it is necessary to design a no-load protection function. When the ultrasonic sound head is detected to be in a no-load state, the high-frequency sinusoidal ultrasonic pulse generation is promptly turned off to prevent damage to the instrument. Among them, the effective value of the high-frequency AC voltage applied to the piezoelectric transducer unit is measured. When it exceeds the threshold value (experiments show that it is 1.4 times the design voltage), it indicates that the no-load phenomenon is generated. At this time, the output of the high-frequency sinusoidal pulse generating circuit is promptly cut off to achieve the effect of protecting the LIPUS circuit board. The entire cutting process is performed by the output and input of the data calculation by the microcontroller unit mentioned above, and finally the alarm circuit is started and the output signal is cut off when the ultrasonic probe is no-loaded to ensure the safety of the instrument during use.

[0081] like Figure 7As shown, for a single-frequency LIPUS therapeutic device, there is no problem of channel switching between multiple frequencies. For a multi-frequency LIPIS therapeutic device, pulsed ultrasound waves of different frequencies must be output according to different ultrasonic therapy symptoms. Currently, the manual operation mode of a toggle switch is mostly used to select the frequency point, which undoubtedly reduces the convenience of the LIPUS therapeutic device and is prone to misoperation. In order to solve the above problems, we have adopted the following measures in the design of the PCB circuit board, based on the programmable production of high-frequency sinusoidal wave pulse signals:

[0082] (1) Piezoelectric ultrasonic transducers with different resonant frequencies are connected in parallel to the output end of the power amplifier circuit unit through an impedance conversion network with a unified electrical interface.

[0083] (2) Each impedance matching network realizes on-off control through an SSR solid-state relay with low insertion loss and sufficient current.

[0084] (3) The instructions issued by the MCU microcontroller unit 21 ensure that only one impedance matching network is connected to the power amplifier circuit unit at the same time. That is, the switching of the multi-frequency (e.g., 1.0MHz, 1.5MHz, 2.0MHz, 2.5MHz, 3.0MHz) channels of the LIPUS therapeutic device is realized through the software control mode, which is significantly more convenient to operate compared with the traditional toggle switch switching mode.

[0085] like Figure 8 As shown in the above text, the LIPUS ultrasonic pulse therapy device not only includes hardware circuit design but also requires the writing of corresponding embedded control programs. The specific control program flow is as follows Figure 8 As shown:

[0086] First, the MCU microcontroller unit 21 controls the register of the DDS chip (the register is a component of the central processing unit, a high-speed storage component with limited storage capacity, which can be used to temporarily store instructions, data and addresses) to generate the required high-frequency sine wave pulse signal.

[0087] In addition, the MCU microcontroller unit 21 collects the voltage signal fed back by the no-load protection circuit through the built-in ADC module (because the common single-chip CPU can only process digital quantities, and the control or measurement of related parameters are often continuously changing analog quantities, such as the known temperature, pressure, speed and voltage, etc., these continuously changing analog quantities must be converted into digital quantities before the single-chip CPU can process them. The process of converting analog quantities into digital quantities is analog / digital (A / D) conversion. The device that can complete analog / digital (A / D) conversion is called an A / D converter or ADC). When the voltage signal exceeds the set threshold, the high-frequency sinusoidal wave pulse signal output of the LIPUS ultrasonic pulse therapy device is automatically cut off.

[0088] Among them, the MCU microcontroller unit 21 collects data from the temperature sensor. If the temperature exceeds the set value, it can also automatically cut off the high-frequency sinusoidal wave pulse signal output of the LIPUS ultrasonic pulse therapeutic device.

[0089] Correspondingly, the MCU microcontroller unit 21 communicates with the serial touch screen through the serial port pins, and automatically selects the frequency channel and the sound intensity level according to the touch screen instructions; the above-mentioned hardware circuit cooperation is required in the process.

[0090] At the same time, the MCU microcontroller unit 21 can set different treatment times such as 5 minutes, 10 minutes, 15 minutes and 20 minutes in sequence through the timer; when the set time is reached, the high-frequency sinusoidal wave ultrasonic pulse output of the LIPUS therapeutic device is immediately cut off.

[0091] In this embodiment, the control program is written in C language and runs on the MCU microcontroller unit 21 .

[0092] In order to realize the above process, the utility model also proposes a method for measuring and calibrating the parameters of the LIPUS ultrasonic pulse therapeutic apparatus, which is as follows:

[0093] LIPUS ultrasonic pulse therapy instrument is essentially a precise ultrasonic emission dose control instrument, which can achieve milliwatt-level ultrasonic energy output control. Its main technical indicators include: 1. Ultrasonic pulse frequency. 2. Ultrasonic pulse mode (duty cycle). 3. Ultrasonic pulse intensity.

[0094] In order to measure the above three indicators of the LIPUS therapeutic device, we proposed the following scheme:

[0095] (1) After the LIPUS therapeutic device is powered on, the ultrasonic pulse frequency is directly measured using a digital oscilloscope.

[0096] (2) After the LIPUS therapeutic device is powered on, the ultrasonic pulse mode is directly measured using a digital oscilloscope.

[0097] (3) After the LIPUS therapeutic device is powered on, the ultrasonic pulse sound intensity is measured indirectly using the equivalent voltage method.

[0098] The principle of indirect measurement of ultrasonic pulse sound intensity is as follows: After the impedance transformation is completed, the impedance of the piezoelectric ultrasonic transducer is pure resistance Rp when it works at the resonant frequency point. Assuming the effective value of the voltage at the piezoelectric transducer terminal is Uo, it is obvious that its effective power Pa is

[0099]

[0100] It can be seen that the sound intensity of the ultrasonic pulse can be converted by measuring the terminal voltage of the piezoelectric transducer under load conditions. This is convenient and low-cost, compared with directly using an expensive dedicated ultrasonic sound intensity tester for measurement.

[0101] Table 3. Effective value Uo of the voltage at the rear end of ultrasonic impedance conversion (unit: mV)

[0102] Gear 1 2 3 4 5 6 7 Pa / mW 136.36 204.55 272.73 409.09 545.45 681.82 818.18 1.0MHz 369.27 452.27 522.24 639.60 738.55 825.72 904.53 1.5MHz 387.29 474.35 547.73 670.82 774.59 866.03 948.68 2.0MHz 304.51 372.95 430.65 527.43 609.02 680.91 745.89 2.5MHz 253.16 310.06 358.03 438.49 506.32 566.09 620.12 3.0MHz 290.76 356.12 411.21 503.62 581.53 650.18 712.23

[0103] Taking the above five-frequency LIPUS therapeutic apparatus as an example, combined with formula (6), the expected effective voltage across the ultrasonic transducer corresponding to the five frequency points and seven sound intensity levels can be calculated as shown in Table 3 above.

[0104] Fig. 9 It is a performance index test block diagram of the LIPUS ultrasonic pulse therapeutic apparatus in an embodiment of the utility model.

[0105] like Fig. 9 As shown above, the test steps of the technical parameters of LIPUS ultrasonic pulse therapy device can be briefly described as follows:

[0106] (1) After the piezoelectric ultrasonic transducer is connected to the LIPUS ultrasonic pulse therapy device host, the piezoelectric transducer probe is placed in the ultrasonic coupling agent to simulate the loaded transmission condition.

[0107] (2) The ultrasonic host is powered on and runs, and the touch screen panel control software sequentially outputs sinusoidal pulse ultrasonic waves with varying frequency, duty cycle and sound intensity. (The touch panel is an OLED liquid crystal touch display, and parameter adjustment and display of various status signs on the therapeutic device can be completed by touching the touch panel; at the same time, for ease of operation, a corresponding mobile phone APP can also be set on the mobile phone end, and Internet information interaction can be established with the host through the mobile phone APP. The connection method can realize information interaction with the MCU microcontroller unit on the single-chip computer through a Bluetooth module or a WiFi module.)

[0108] (3) Use a high-frequency oscilloscope to read and record the waveform of the sinusoidal ultrasonic pulse, and record the ultrasonic pulse frequency, ultrasonic pulse mode and the effective value of the voltage at the piezoelectric ultrasonic transducer terminal.

[0109] Based on 3MHz@150mW / cm 2 The ultrasonic waveform corresponding to the gear position shows that its frequency deviation is 0.4%; the effective voltage value of 659mV is close to the theoretical value of 650.18mV, and the ultrasonic output dose control is more precise.

[0110] It should be noted that: the utility model establishes a LIPUS energy conversion model and uses high-frequency electronic technology and embedded software technology to achieve multi-parameter adjustment of the frequency, sound intensity and pulse mode of the LIPUS therapeutic instrument, provides support for clinical medical trials of LIPUS treatment, and helps to select appropriate LIPUS treatment parameters for different symptoms. It has important theoretical research and medical application value.

[0111] Example 2

[0112] In order to provide a wider range of options for clinical medical research on LIPUS treatment, we have trial-produced a multi-parameter adjustable LIPUS ultrasonic pulse therapy device. The adjustable parameters are as follows:

[0113] 1. Ultrasonic center frequency is adjustable: 1.0MHz-3.0MHz, 0.5MHz step;

[0114] 2. Output ultrasonic sound intensity 30mW / cm 2 ~180mW / cm 2 A total of 7 levels are adjustable;

[0115] 3. Pulse mode: 1:1, 1:2, 1:3, 1:4 adjustable.

[0116] 4. Treatment time: 5 minutes, 10 minutes, 15 minutes, 20 minutes adjustable.

[0117] In addition, according to the national standards for ultrasonic therapy, temperature alarm and no-load alarm are set to ensure the safety of the LIPUS ultrasonic pulse therapeutic device during use. It should be pointed out that the method and circuit implementation process involved in the utility model are also applicable to other multi-parameter LIPUS therapeutic devices.

[0118] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the principle of the present invention. These improvements and supplements should also be regarded as the protection scope of the present invention.

Claims

1. A portable LIPUS ultrasonic pulse therapeutic device, characterized in that: The therapeutic device comprises a housing, a unit circuit in the housing, a touch panel on the housing, a voltage sampling circuit interface at one end of the housing, and a plurality of ultrasonic probe interfaces at the other end of the housing; Wherein, the touch panel, the voltage sampling circuit interface, and the ultrasonic probe interface are electrically connected to the unit circuit respectively; The unit circuit includes a microcontroller unit, a signal generator unit, a program-controlled amplifier unit, a PA power amplifier unit and a piezoelectric transducer unit; Wherein, the microcontroller unit adopts PWM technology to control the frequency and pulse width of the modulation signal by outputting a pulse square wave to obtain output signals with different duty ratios via voltage, and the microprocessor is connected to the voltage sampling circuit through the A / D conversion interface to monitor the output signal voltage change and start the alarm circuit and cut off the output signal when the ultrasonic probe is unloaded; In addition, the microcontroller unit also controls the data operation output and input of the signal generator unit, the programmable amplifier unit, the PA power amplifier unit and the piezoelectric transducer unit.

2. The portable LIPUS ultrasonic pulse therapeutic device according to claim 1, characterized in that: The signal generator unit is a high-frequency sine wave signal generator that uses DDS chip direct digital frequency synthesis technology and can control the output of stable ultrasonic pulses at 5 different frequencies: 1.0MHz, 1.5MHz, 2.0MHz, 2.5MHz and 3.0MHz; Among them, the ultrasonic pulse of each frequency point contains 7 levels of sound intensity.

3. The portable LIPUS ultrasonic pulse therapeutic device according to claim 1, characterized in that: The signal generator unit is a high-frequency sine wave signal generator with a pulse duty ratio of 20%-50% which is continuously adjustable.

4. The portable LIPUS ultrasonic pulse therapeutic device according to claim 1, characterized in that: The program-controlled amplifier unit is used to perform program-controlled amplification on the generated high-frequency sine wave signal, and the amplification factor of the program-controlled amplifier unit is 2 times or 3 times.

5. The portable LIPUS ultrasonic pulse therapeutic device according to claim 1, characterized in that: The PA power amplifier unit includes a push-pull power amplifier circuit without an output transformer.

6. The portable LIPUS ultrasonic pulse therapeutic device according to claim 1, characterized in that: The piezoelectric transducer unit uses the inverse piezoelectric effect of the piezoelectric ceramic sheet to convert the input high-frequency sinusoidal wave pulse signal into sinusoidal pulse ultrasonic energy for output; Wherein, each frequency gear adopts a piezoelectric transducer with an effect resonant frequency; Correspondingly, the piezoelectric transducer unit is also connected to an impedance matching circuit unit that matches it.

7. The portable LIPUS ultrasonic pulse therapeutic device according to claim 6, characterized in that: The static capacitance of the piezoelectric transducer unit is Cp, and an inductor L is connected in parallel at both ends of the piezoelectric transducer unit to form an LC parallel resonant network; The static capacitance Cp is tuned at the resonant frequency fo of the piezoelectric transducer unit to achieve the conversion from the capacitive load to the pure resistive load, and the load resistance value after the conversion is Rp; The LC parallel resonant frequency formula is as follows: Since the unit of parallel inductance value is mostly uH level, in order to facilitate calculation, the LC parallel resonant frequency formula is transformed into: Wherein, Cp represents the static capacitance, fo represents the static capacitance Cp is tuned at the resonant frequency of the piezoelectric transducer unit.

8. The portable LIPUS ultrasonic pulse therapeutic apparatus according to claim 1, characterized in that: The touch panel is an OLED liquid crystal touch display, and parameter adjustment and display of status signs on the therapeutic device can be completed by touching the touch panel.

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