Radio frequency therapeutic apparatus power automatic calibration device and calibration method

Abstract

The invention relates to the technical field of radio frequency therapeutic apparatuses, and discloses an automatic power calibration device for a radio frequency therapeutic apparatus. Comprising a base, connecting plates are fixedly connected to the outer surface of the base, wheel seats are movably connected to the lower surfaces of the connecting plates through bearings, moving wheels are movably connected to the side surfaces of the wheel seats through bearings, a machine base is fixedly connected to the upper surface of the base, and a platform is fixedly connected to the upper surface of the machine base; a display is arranged on the upper surface of the platform, a calibrator is arranged on the front surface of the machine base, the calibrator is low in cost, a professional power meter is not needed, multiple devices are supported to share tools, the cost is further reduced, multi-gear programmable impedance loads such as 50 ohms, 200 ohms, 500 ohms and 1k ohms are arranged in the platform, the platform communicates with an electric cautery instrument through an RS485 / USB serial port, remote load switching is supported, and the platform is convenient to use. A temperature coefficient lt is selected as a load material; a precise non-inductive resistor with the temperature of 0.01% / DEG C is adopted, the stability and the operation convenience are ensured, one-key automatic calibration is realized, and the time consumed for one time is lt; and 3 minutes.

Description

Technical Field

[0001] This invention relates to the field of radiofrequency therapy device technology, specifically to an automatic power calibration device and calibration method for radiofrequency therapy devices. Background Technology

[0002] Radiofrequency therapy devices utilize low-frequency electromagnetic waves to act on diseased tissues, causing polarized water molecules within the tissue to move at high speeds, generating heat (i.e., endogenous heat effect). At low temperatures, this causes proteins to coagulate and lose their activity. Finally, through the body's rejection process, the proteins slough off, thus achieving the therapeutic goal. Radiofrequency generates radiofrequency waves at a specific depth under the skin, acting on water molecules within collagen. The bipolar water molecules vibrate and rotate at high speed, generating heat through friction, achieving the effect of heating dermal collagen. The radiofrequency device emits low-frequency electromagnetic waves (radiofrequency waves) that penetrate the epidermis to the dermis, generating heat through the high-speed friction of water molecules (endogenous heat effect). This gentle heating causes collagen fibers to contract and initiate repair mechanisms, stimulating the production of new collagen. During treatment, the heating of dermal collagen fibers first causes them to contract, tightening loose skin and wrinkles. Subsequently, the thermal effect in the dermis promotes collagen proliferation, and the newly generated collagen rearranges and increases in quantity, repairing the aged and damaged collagen layer, thereby achieving the effect of wrinkle reduction and skin tightening. Multiple positive and negative electrodes act at the same interface, and the focused current makes the treatment energy more precise, concentrated, and controllable, heating deeper layers. It can simultaneously heat the dermis and subcutaneous fat layer, tightening and wrinkle removal while also having fat-reducing and shaping effects. The energy penetrates deeply, but the heat is dispersed, making it very safe. Treatment of the body requires no pre- or post-treatment cooling, is painless, will not cause burns, is safe and comfortable, requires no consumables, and has minimal operating costs. The treatment head is very lightweight, and the operator's grip is close to the electrodes and skin, reducing fatigue. The octagonal treatment head is used for body treatment, and the diamond treatment head is used for facial treatment. To achieve constant power output, radiofrequency therapy devices need to perform impedance detection on the target tissue. Based on the detected load impedance and target power, the required output voltage is calculated, and then the target voltage is output by adjusting the duty cycle. Since the dynamic change of load impedance under the same conditions causes output voltage fluctuations, impedance calibration and voltage calibration for different impedances are required to achieve constant power output. Radiofrequency therapy devices face problems such as relying on precision instruments, high operational difficulty, high cost, and the need for a strict laboratory environment during power calibration. Summary of the Invention

[0003] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an automatic power calibration device and method for radiofrequency therapy instruments. Simply connect the calibrator to the therapy instrument, and the instrument can automatically calibrate by switching the calibration fixture to the corresponding impedance via serial port control. Users can customize the calibration impedance range according to clinical needs. The device collects voltage and current data during calibration using an ADC, fitting radiofrequency voltage curves for different impedances at the same duty cycle and for different impedances with different duty cycles and radiofrequency voltage curves. In actual use, the current impedance is detected based on the impedance detection curve, and the duty cycle is adjusted according to the radiofrequency voltage curve to output the target voltage. The device incorporates multiple programmable impedance loads, such as 50Ω, 200Ω, 500Ω, and 1kΩ. It communicates with the electrocautery instrument via an RS485 / USB serial communication module, supporting remote load switching. The load material is a precision non-inductive resistor with a temperature coefficient <0.01% / ℃ to ensure stability. The device offers advantages such as convenient operation (one-click automatic calibration), a single calibration time of <3 minutes, and rapid automatic calibration, solving the problems of reliance on precision instruments, high operational difficulty, high cost, and the need for a strict laboratory environment.

[0004] (II) Technical Solution To solve the above-mentioned technical problems, the present invention provides the following technical solution: A base is included, with connecting plates fixedly connected to the outer surface of the base. A wheel seat is movably connected to the lower surface of the connecting plate via bearings. A movable wheel is movably connected to the side surface of the wheel seat via bearings. A machine base is fixedly connected to the upper surface of the base. A platform is fixedly connected to the upper surface of the machine base. A display is provided on the upper surface of the platform. A calibrator is provided on the front surface of the machine base. A therapeutic instrument is embedded inside the platform, and the therapeutic instrument is electrically connected to the calibrator via wires.

[0005] Preferably, the calibrator includes a serial communication module, a main control chip, a relay array, an RF input interface, a non-inductive resistor array, and a power supply module. The power supply module, the serial communication module, the main control chip, the relay array, the RF input interface, and the non-inductive resistor array are all electrically connected to the calibrator, and the RF input interface is electrically connected to the therapeutic instrument.

[0006] Preferably, the relay array uses a solid-state relay matrix to switch loads, and the solid-state relay matrix connects multiple precision impedance loads with different resistance values.

[0007] Preferably, the base has a built-in radio frequency generation module, which is electrically connected to the main control chip, and the serial communication module is configured to send impedance switching commands to the calibrator.

[0008] Preferably, the main control chip is configured with a PWM generation module, a load impedance detection module, a storage module, and an RF voltage sampling module. The RF voltage sampling module and the PWM adjustment module form a closed-loop control system. The storage module stores the duty cycle-voltage relationship curves corresponding to each load impedance. The main control chip establishes command communication with the high-frequency electrocautery instrument through a serial communication module. The storage module adopts a dual-zone storage structure, including a calibration parameter storage area and a runtime lookup table area, which supports online updates of calibration parameters.

[0009] Preferably, the solid-state relay matrix has a 1ms-level switching response time and uses low-capacitance MOSFET relays to form a multi-channel switching network.

[0010] Preferably, the precision impedance load is a metal foil resistor with a temperature coefficient of less than 0.01% / ℃, including four standard resistance value modules of 50Ω, 200Ω, 500Ω and 1kΩ.

[0011] Preferably, the duty cycle-voltage relationship curve is generated by performing cubic polynomial fitting on the corresponding voltage values ​​of four duty cycle reference points of 3%, 5%, 10%, and 20% under each load, obtained experimentally.

[0012] Preferably, the load impedance detection module adopts the four-wire Kelvin detection method and is connected in parallel to a high-precision ADC sampling circuit in the RF output circuit.

[0013] An automatic power calibration method for a radiofrequency therapy device includes the following steps: S1. Establish command connection between the treatment device and the calibrator through the serial communication module, activate the radio frequency generation module and closed-loop control system of the main control chip, initialize the dual-zone storage structure of the storage module, and clear the lookup table area during operation. S2, the solid-state relay matrix switches four groups of precision impedance loads of 50Ω / 200Ω / 500Ω / 1kΩ at a speed of 1ms. The actual load impedance value is measured in real time using the four-wire Kelvin detection method, and the impedance feedback data is obtained by a high-precision ADC sampling circuit. S3. Voltage sampling is performed at four reference duty cycle points of 3% / 5% / 10% / 20% for each load impedance. The PWM generation module outputs a preset duty cycle signal, the RF voltage sampling module collects the output voltage waveform, records the duty cycle-voltage correspondence data, and uses a cubic polynomial fitting algorithm to generate a nonlinear calibration curve. S4. Write the fitted calibration curve into the calibration parameter area of ​​the storage module, establish the mapping relationship between the runtime lookup table area and the calibration parameters, and support the maintenance of data consistency between the two areas during online updates; S5. During operation, the load impedance changes are monitored in real time. The duty cycle-voltage curve of the corresponding lookup table area is called according to the current impedance value. The PWM duty cycle output is dynamically adjusted through the PID algorithm. The error between the RF voltage sampling value and the set value is controlled within ±1%. The temperature characteristics of the metal foil resistor are periodically checked. S6. Utilize a temperature coefficient of 0.01% / ℃ to dynamically correct the impedance value, update the temperature compensation parameters in the storage module, automatically traverse all load impedance combinations, compare the deviation between the measured power value and the set value, generate a calibration verification report, and output it through the display.

[0014] Compared with the prior art, the present invention provides an automatic power calibration device and calibration method for radiofrequency therapy devices, which has the following beneficial effects: 1. This invention only requires connecting the calibrator to the treatment device. The radiofrequency therapy device can automatically calibrate by controlling the calibration fixture to switch to the corresponding impedance via serial port. Users can customize the calibration impedance range according to clinical needs. The voltage and current during calibration are collected by ADC, and the radiofrequency voltage curves of different impedances under the same duty cycle and the duty cycle and radiofrequency voltage curves of different impedances are fitted. In actual use, the current impedance is detected according to the impedance detection curve, and then the duty cycle is adjusted according to the duty cycle and radiofrequency voltage curve to output the target voltage. It has multiple built-in programmable impedance loads, such as 50Ω, 200Ω, 500Ω, 1kΩ, etc. It communicates with the electrocautery device through RS485 / USB serial communication module, supports remote load switching, and the load material is a precision non-inductive resistor with a temperature coefficient of <0.01% / ℃ to ensure stability. The operation is convenient with one-click automatic calibration, and the single calibration time is <3 minutes, which can quickly and automatically calibrate. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the calibrator flow structure of the present invention; Figure 3 This is a schematic diagram of the main control chip process structure of the present invention; Figure 4 This is a schematic diagram of the procedure flow structure during calibration of the present invention; Figure 5 This is a schematic diagram of the load switching principle structure of the solid-state relay matrix of the present invention.

[0016] The components include: 1. base; 2. wheel seat; 3. connecting plate; 4. platform; 5. therapeutic instrument; 6. display; 7. base; 8. calibrator; and 9. moving wheels. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1: Please see Figure 1-5 An automatic power calibration device and calibration method for a radiofrequency therapy device includes a base 1. A connecting plate 3 is fixedly connected to the outer surface of the base 1. A wheel seat 2 is movably connected to the lower surface of the connecting plate 3 via a bearing. A movable wheel 9 is movably connected to the side surface of the wheel seat 2 via a bearing. A base 7 is fixedly connected to the upper surface of the base 1. A platform 4 is fixedly connected to the upper surface of the base 7. A display 6 is provided on the upper surface of the platform 4. A calibrator 8 is provided on the front surface of the base 7. A therapy device 5 is fitted inside the platform 4. The therapy device 5 is electrically connected to the calibrator 8 via a wire.

[0019] The base 1 is connected to the wheel seat 2 with movable wheels 9 via the connecting plate 3, forming a movable support structure. The movable wheel 9's bearing movable design allows the entire device to move freely to the required position, and the wheel seat 2 provides stable support. The interlocking connection design inside the platform 4 ensures the physical fixation and electrical connection between the therapeutic instrument 5 and external components. The therapeutic instrument 5 is electrically connected to the calibrator 8 via wires. The calibrator 8 is responsible for adjusting output parameters and calibrating signals. The display 6 provides a treatment status monitoring interface, forming a closed-loop control system of "calibrator 8 - therapeutic instrument 5 - display 6" to ensure treatment accuracy. During treatment, the calibrator 8 transmits the adjusted electrical signal to the therapeutic instrument 5 to implement treatment, and simultaneously feeds back real-time data through the display 6.

[0020] The calibrator 8 includes a serial communication module, a main control chip, a relay array, an RF input interface, a non-inductive resistor array, and a power supply module. The power supply module, serial communication module, main control chip, relay array, RF input interface, and non-inductive resistor array are all electrically connected to the calibrator 8. The RF input interface is electrically connected to the therapeutic instrument 5. The relay array uses a solid-state relay matrix to switch loads, connecting multiple precision impedance loads with different resistance values. The base 7 has a built-in RF generation module, which is electrically connected to the main control chip. The serial communication module is configured to send impedance switching commands to the calibrator 8. The main control chip includes a PWM generation module, a load impedance detection module, a storage module, and an RF voltage sampling module. The RF voltage sampling module and the PWM adjustment module form a closed-loop control system. The storage module stores the duty cycle corresponding to each load impedance. - Voltage relationship curve: The main control chip establishes command communication with the high-frequency electrocautery instrument through the serial communication module. The storage module 113 adopts a dual-zone storage structure, including a calibration parameter storage area and a runtime lookup table area, which supports online updating of calibration parameters. The solid-state relay matrix has a 1ms-level switching response time and uses low-capacitance MOSFET relays to form a multi-channel switching network. The precision impedance load uses metal foil resistors with a temperature coefficient of less than 0.01% / ℃, including four standard resistance value modules of 50Ω, 200Ω, 500Ω, and 1kΩ. The duty cycle-voltage relationship curve is generated by cubic polynomial fitting of the corresponding voltage values ​​of four duty cycle reference points of 3%, 5%, 10%, and 20% under each load, obtained by experimental testing. The load impedance detection module adopts the four-wire Kelvin detection method and is connected in parallel to a high-precision ADC sampling circuit in the RF output circuit.

[0021] The main control chip acts as the central hub, coordinating the operation of the serial communication, PWM generation, load switching, and data acquisition and storage modules. The power supply module provides a stable power supply to all functional modules. External control commands can be received through the RS232 / 485 serial communication module. The main control chip parses the commands and activates the corresponding functional modules. The solid-state relay matrix completes the target impedance switching within 1ms. Selectable precision loads are 50Ω / 200Ω / 500Ω / 1kΩ. The four-wire Kelvin method can detect and eliminate the influence of contact resistance, accurately measuring the actual load impedance. RF sampling: A high-precision ADC (24bit) acquires the RF output voltage waveform in real time. The RF voltage sampling data is fed back to the PWM generation module, dynamically adjusting the PWM duty cycle to maintain the preset output voltage. The control cycle is <10ms, achieving fast response. Calibration area: stores the original polynomial coefficients. Running area: stores the optimized duty cycle-voltage lookup table, supporting online updates of calibration parameters without interrupting the current operation. The treatment device 5 can control the calibration fixture to switch to the corresponding impedance through the serial communication module to achieve automatic calibration.

[0022] Example 2: An automatic power calibration method for a radiofrequency therapy device includes the following steps: S1. Establish command connection between the treatment device and the calibrator through the serial communication module, activate the radio frequency generation module and closed-loop control system of the main control chip, initialize the dual-zone storage structure of the storage module, and clear the lookup table area during operation. S2, the solid-state relay matrix switches four groups of precision impedance loads of 50Ω / 200Ω / 500Ω / 1kΩ at a speed of 1ms. The actual load impedance value is measured in real time using the four-wire Kelvin detection method, and the impedance feedback data is obtained by a high-precision ADC sampling circuit. S3. Voltage sampling is performed at four reference duty cycle points of 3% / 5% / 10% / 20% for each load impedance. The PWM generation module outputs a preset duty cycle signal, the RF voltage sampling module collects the output voltage waveform, records the duty cycle-voltage correspondence data, and uses a cubic polynomial fitting algorithm to generate a nonlinear calibration curve. S4. Write the fitted calibration curve into the calibration parameter area of ​​the storage module, establish the mapping relationship between the runtime lookup table area and the calibration parameters, and support the maintenance of data consistency between the two areas during online updates; S5. During operation, the load impedance changes are monitored in real time. The duty cycle-voltage curve of the corresponding lookup table area is called according to the current impedance value. The PWM duty cycle output is dynamically adjusted through the PID algorithm. The error between the RF voltage sampling value and the set value is controlled within ±1%. The temperature characteristics of the metal foil resistor are periodically checked. S6. Utilize a temperature coefficient of 0.01% / ℃ to dynamically correct the impedance value, update the temperature compensation parameters in the storage module, automatically traverse all load impedance combinations, compare the deviation between the measured power value and the set value, generate a calibration verification report, and output it through the display.

[0023] During use, the radiofrequency therapy device controls the radiofrequency voltage by adjusting the PWM duty cycle, thereby achieving the target output power. According to the power formula P = U... 2 When the radiofrequency therapy device outputs the target power, it needs to know the current load impedance R. Since the duty cycle of the PWM controlled by the radiofrequency voltage is consistent, the voltage across different loads will differ. Therefore, it is necessary to obtain the duty cycle versus voltage curve under different loads. This is achieved by obtaining the voltage corresponding to different impedances (e.g., 50Ω, 200Ω, 500Ω, 1kΩ, etc.) and duty cycles (e.g., 3%, 5%, 10%, 20%) to fit the duty cycle versus voltage curve under different loads. Using this duty cycle versus voltage curve, the radiofrequency therapy device first obtains the current load impedance, then looks up the target duty cycle in a table and adjusts the output voltage using PWM. The device can then automatically calibrate by controlling the calibration fixture to switch to the corresponding impedance via the serial communication module.

[0024] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic power calibration device for a radiofrequency therapy instrument, comprising a base (1), characterized in that: The outer surface of the base (1) is fixedly connected to a connecting plate (3). The lower surface of the connecting plate (3) is movably connected to a wheel seat (2) via a bearing. The side surface of the wheel seat (2) is movably connected to a moving wheel (9) via a bearing. The upper surface of the base (1) is fixedly connected to a base (7). The upper surface of the base (7) is fixedly connected to a platform (4). The upper surface of the platform (4) is provided with a display (6). The front surface of the base (7) is provided with a calibrator (8). The inside of the platform (4) is fitted with a therapeutic instrument (5). The therapeutic instrument (5) is electrically connected to the calibrator (8) via a wire.

2. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The calibrator (8) includes a serial communication module, a main control chip, a relay array, an RF input interface, a non-inductive resistor array, and a power supply module. The power supply module, the serial communication module, the main control chip, the relay array, the RF input interface, and the non-inductive resistor array are all electrically connected to the calibrator (8). The RF input interface is electrically connected to the therapeutic instrument (5).

3. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The relay array uses a solid-state relay matrix to switch the load, and the solid-state relay matrix connects multiple precision impedance loads with different resistance values.

4. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The base (7) has a built-in radio frequency generation module, and the built-in radio frequency generation module is electrically connected to the main control chip. The serial communication module is configured to send impedance switching commands to the calibrator (8).

5. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The main control chip is equipped with a PWM generation module, a load impedance detection module, a storage module, and an RF voltage sampling module. The RF voltage sampling module and the PWM adjustment module form a closed-loop control system. The storage module stores the duty cycle-voltage relationship curves corresponding to each load impedance. The main control chip establishes command communication with the high-frequency electrocautery instrument through a serial communication module. The storage module adopts a dual-zone storage structure, including a calibration parameter storage area and a runtime lookup table area, which supports online updates of calibration parameters.

6. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The solid-state relay matrix has a 1ms-level switching response time and uses low-capacitance MOSFET relays to form a multi-channel switching network.

7. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The precision impedance load uses metal foil resistors with a temperature coefficient of less than 0.01% / ℃, including four standard resistance value modules: 50Ω, 200Ω, 500Ω, and 1kΩ.

8. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The duty cycle-voltage relationship curve was generated by performing a cubic polynomial fitting on the corresponding voltage values ​​of four duty cycle reference points (3%, 5%, 10%, and 20%) under each load, obtained through experiments.

9. The automatic power calibration device for a radiofrequency therapy instrument according to claim 1, characterized in that: The load impedance detection module adopts the four-wire Kelvin detection method and is connected in parallel to a high-precision ADC sampling circuit in the RF output circuit.

10. A method for automatic power calibration of a radiofrequency therapy device according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Establish command connection between the treatment device and the calibrator through the serial communication module, activate the radio frequency generation module and closed-loop control system of the main control chip, initialize the dual-zone storage structure of the storage module, and clear the lookup table area during operation. S2, the solid-state relay matrix switches four groups of precision impedance loads of 50Ω / 200Ω / 500Ω / 1kΩ at a speed of 1ms. The actual load impedance value is measured in real time using the four-wire Kelvin detection method, and the impedance feedback data is obtained by a high-precision ADC sampling circuit. S3. Voltage sampling is performed at four reference duty cycle points of 3% / 5% / 10% / 20% for each load impedance. The PWM generation module outputs a preset duty cycle signal, the RF voltage sampling module collects the output voltage waveform, records the duty cycle-voltage correspondence data, and uses a cubic polynomial fitting algorithm to generate a nonlinear calibration curve. S4. Write the fitted calibration curve into the calibration parameter area of ​​the storage module, establish the mapping relationship between the runtime lookup table area and the calibration parameters, and support the maintenance of data consistency between the two areas during online updates; S5. During operation, the load impedance changes are monitored in real time. The duty cycle-voltage curve of the corresponding lookup table area is called according to the current impedance value. The PWM duty cycle output is dynamically adjusted through the PID algorithm. The error between the RF voltage sampling value and the set value is controlled within ±1%. The temperature characteristics of the metal foil resistor are periodically checked. S6. Utilize a temperature coefficient of 0.01% / ℃ to dynamically correct the impedance value, update the temperature compensation parameters in the storage module, automatically traverse all load impedance combinations, compare the deviation between the measured power value and the set value, generate a calibration verification report, and output it through the display.

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