Intermediate frequency interference current output control method and system

Abstract

The invention discloses an intermediate frequency interference current output control method and system, and the method comprises the steps: obtaining an interference mode, and obtaining a corresponding waveform parameter based on the interference mode; according to the waveform parameter, dynamically determining a key frequency parameter of an output waveform in the current output time period, and calculating the retention time of the key frequency parameter; generating a reference waveform signal based on the currently determined key frequency parameter; and within the holding time, modulating and shaping the reference waveform signal to form an intermediate-frequency interference current waveform signal required by treatment, and outputting the intermediate-frequency interference current waveform signal. According to the invention, through software configuration, key frequency parameters can be dynamically determined and the retention time of the key frequency parameters can be calculated, so that each frequency component acts on human tissues within the optimal action time, and higher-precision time sequence control on intermediate-frequency interference current is realized; and the key frequency parameters can be adaptively changed according to the input interference mode and the waveform parameters thereof, so that the treatment is flexible and configurable.

Description

Technical Field

[0001] This invention relates to the field of medical equipment technology, and more specifically to a method and system for controlling the output of intermediate frequency interference current. Background Technology

[0002] Interferential electrotherapy is a physical therapy device that outputs two sets of medium-frequency alternating currents of different frequencies to act crosswise on deep tissues of the human body, producing low-frequency biological effects with therapeutic effects. It can be widely used in the treatment of neuropathy, muscle spasms, arthritis, sports injuries and chronic pain.

[0003] The treatment and output characteristics of existing intermediate frequency interference electrotherapy devices are largely determined by hardware circuits, resulting in fixed functions and a single treatment method. Secondly, most current devices generally use analog oscillation circuits or basic digital clock frequency division to generate intermediate frequency signals, obtaining the frequency difference required for treatment through the frequency difference. The output parameters (especially frequency and time) rely heavily on simple timers or analog circuits, resulting in insufficient output control precision and inaccurate treatment output, thus limiting the treatment effect and failing to meet rehabilitation needs. Summary of the Invention

[0004] This invention provides a method and system for controlling the output of intermediate frequency interference current, in order to solve the technical problem that the treatment and output characteristics of existing intermediate frequency interference electrotherapy devices are largely determined by hardware circuits, resulting in fixed treatment and insufficient output control precision, which limits the treatment effect and fails to meet rehabilitation needs.

[0005] To solve the above-mentioned technical problems, in a first aspect, the present invention provides a method for controlling the output of intermediate frequency interference current, comprising: Obtain the interference pattern, and obtain the corresponding waveform parameters based on the interference pattern; Based on the waveform parameters, the key frequency parameters of the output waveform within the current output time period are dynamically determined, and the holding time of the key frequency parameters is calculated. Based on the currently determined key frequency parameters, a reference waveform signal is generated; During the holding time, the reference waveform signal is modulated and shaped to form the intermediate frequency interference current waveform signal required for treatment, and then output.

[0006] Secondly, the present invention provides a medium-frequency interference current output control system, comprising: The main control unit is used to acquire the interference mode input to the intermediate frequency electrotherapy device and acquire the waveform parameters corresponding to the interference mode; and based on the waveform parameters, dynamically determine the key frequency parameters of the output waveform within the current output time period, calculate the holding time of the key frequency parameters; and calculate the waveform frequency of each output channel based on the currently determined key frequency parameters. The base frequency control unit, connected to the main control unit, is used to generate corresponding reference waveform signals based on the waveform frequency of each output channel; A modulation output unit, connected to the baseband control unit, is used to independently modulate and shape the reference waveform signal during the holding time to form the intermediate frequency interference current waveform signal required for treatment, and then output it.

[0007] Compared with existing technologies, the intermediate frequency interference current output control method of this invention dynamically determines the key frequency parameters of the output waveform within the current output time period based on the waveform parameters of the input interference mode, calculates the holding time of the key frequency parameters, and generates a reference waveform signal based on the currently determined key frequency parameters. During the holding time, the reference waveform signal is modulated and shaped to form the intermediate frequency interference current waveform signal required for treatment. It can be seen that this invention, through software configuration, can dynamically determine the key frequency parameters and calculate their holding time, so that each frequency component acts on human tissue within its optimal action time, achieving higher precision timing control of the intermediate frequency interference current, avoiding ineffective or excessive stimulation. Moreover, the key frequency parameters of the output interference current can be adaptively changed according to the input interference mode and its waveform parameters, making the treatment flexible and configurable. When used, it can also significantly enhance the targeting and effectiveness of electrical stimulation on neuromuscular tissue, thereby further improving the treatment effect and meeting complex rehabilitation needs. Attached Figure Description

[0008] Figure 1 This is a flowchart illustrating a specific embodiment of the intermediate frequency interference current output control method of the present invention.

[0009] Figure 2 for Figure 1 The diagram shows the specific flow chart of S20 in the intermediate frequency interference current output control method of the present invention.

[0010] Figure 3 for Figure 2 The diagram shows a detailed flow chart of S22 in the intermediate frequency interference current output control method of the present invention.

[0011] Figure 4 This is a schematic diagram of the structure of a specific embodiment of the intermediate frequency interference current output control system of the present invention. Detailed Implementation

[0012] To enable those skilled in the art to more clearly understand the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0013] The intermediate frequency interference current output control method of this invention can be applied to intermediate frequency electrotherapy devices. Through software configuration, key frequency parameters can be dynamically determined and their holding time calculated, so that each frequency component acts on human tissue within its optimal action time. This achieves higher precision timing control of the intermediate frequency interference current, avoiding ineffective or excessive stimulation. Furthermore, the key frequency parameters of the output interference current can be adaptively changed according to the input interference mode and its waveform parameters, making treatment flexible and configurable. This enables personalized and diversified treatment modes, thereby effectively enhancing the targeting, safety, and overall therapeutic effect of intermediate frequency interference electrotherapy, and meeting complex rehabilitation needs.

[0014] Reference Figure 1 , Figure 1 This is a flowchart illustrating a specific embodiment of the intermediate frequency interference current output control method of the present invention. In the embodiment shown in the figure, the intermediate frequency interference current output control method includes the following steps S10-S50: S10. Obtain the interference mode and obtain the corresponding waveform parameters based on the interference mode.

[0015] Users can select the interference mode through the human-machine interface of the intermediate frequency interference electrotherapy device, and select / set the waveform parameters of the corresponding interference mode. In this step, the selected interference mode and the corresponding waveform parameters of the interference mode are obtained, so as to control the output of the electrotherapy device according to the waveform parameters of the interference mode.

[0016] Understandably, users can also select the output channel and working time, or the output channel and working time can be pre-bound or defaulted using the interference mode, and the output channel is a non-empty multi-channel combination, which can be any two-channel combination or any three-channel combination.

[0017] In this invention, the interference modes may include interference mode 1, interference mode 2 and interference mode 3, wherein interference mode 1, interference mode 2 and interference mode 3 may be difference frequency interference electrical mode, vector interference electrical mode and amplitude modulation interference electrical mode, respectively, and the waveform parameters are different according to different modes.

[0018] If the selected interference mode is a difference frequency interference electrical mode, the waveform parameters must include at least the fundamental frequency, difference frequency, difference frequency variation mode, difference frequency variation range, difference frequency variation period, intensity parameter, and envelope parameter; if the selected interference mode is a vector interference electrical mode, the waveform parameters must include at least the fundamental frequency, difference frequency, vector time, difference frequency variation mode, difference frequency variation range, difference frequency variation period, intensity parameter, and envelope parameter; if the selected interference mode is an amplitude modulation interference electrical mode, the waveform parameters must include at least the fundamental frequency, difference frequency, modulation frequency, difference frequency / frequency modulation variation mode, difference frequency / frequency modulation variation range, difference frequency / frequency modulation variation period, intensity parameter, and envelope parameter.

[0019] S20. Based on the waveform parameters, dynamically determine the key frequency parameters of the output waveform within the current output time period, and calculate the holding time of the key frequency parameters.

[0020] In this invention, the key frequency parameter values ​​to be output are continuously and dynamically determined based on the change pattern, range, and period of the key frequency parameters. Specifically, if the key frequency parameter is a difference frequency, then dynamically determining the key frequency parameters of the output waveform within the current output time period includes: continuously and dynamically determining the difference frequency value to be output based on the change pattern, range, and period of the difference frequency; and if the key frequency parameter includes synchronously changing difference frequency and modulation frequency, then dynamically determining the key frequency parameters of the output waveform within the current output time period includes: continuously generating synchronous difference frequency change sequences and modulation frequency change sequences based on a shared change pattern and period, combined with the difference frequency change range and the modulation frequency change range, to determine all difference frequency values ​​and modulation frequency values ​​of the output waveform within the current output time period. It can be understood that the difference frequency change range and the modulation frequency change range can be the same or different.

[0021] For example, if the interference modes are interference mode 1 and interference mode 2, and the key frequency parameter is the difference frequency, then the difference frequency value of the output waveform within the current output time period is dynamically determined based on the difference frequency, the difference frequency change mode (such as constant, sweep, and random), the difference frequency change range, and the change period in the waveform parameters. For example, when the difference frequency change mode is sweep, the difference frequency value changes cyclically within the difference frequency change range in the order of small to large and then large to small according to the difference frequency change period, and switches to the next value at the end of the holding time of each difference frequency value.

[0022] Understandably, if the interference mode is interference mode 3, and the key frequency parameters include the synchronously changing difference frequency and the modulation frequency, the difference frequency and modulation frequency of the output waveform in the current output time period can be dynamically determined based on the difference frequency, the modulation frequency, and the shared difference frequency / modulation change mode and the difference frequency / modulation change period, combined with their respective change ranges.

[0023] Preferably, in this invention, to ensure that each key frequency parameter has a complete cycle, the holding time is allocated according to the physiological response characteristics of different frequencies using the following intelligent holding time allocation algorithm to optimize the treatment effect or measurement accuracy.

[0024] Specifically, such as Figure 2 As shown, the holding time for calculating the key frequency parameter in step S20 includes the following steps S21-S23: S21. Calculate the theoretical average hold time based on the change period and change range of the key frequency parameters in the waveform parameters.

[0025] In this step, if the key frequency parameter includes the difference frequency, the theoretical average hold time is calculated based on the difference frequency change period and difference frequency change range in the waveform parameters. In this embodiment, the theoretical average hold time t0 is calculated according to the formula t0 = T * 1000 / (Fn - Fm +1), where T represents the difference frequency change period in seconds, T * 1000 is the period time in milliseconds, Fn and Fm represent the upper and lower limits of the difference frequency change range, respectively, and (Fn - Fm) + 1 represents the total number of difference frequency points within the difference frequency change range. That is, within the difference frequency change period T, when traversing all integer difference frequency points from Fm to Fn, the theoretical average hold time t0 allocated to each difference frequency point is calculated.

[0026] If the key frequency parameters include the difference frequency and the modulation frequency, then based on the difference frequency / modulation variation period shared by the waveform parameters, and according to the difference frequency variation range and the modulation frequency variation range respectively, two theoretical average hold times required to traverse all frequency points within their respective ranges are calculated. Understandably, if the difference frequency variation range and the modulation frequency variation range are the same, then the theoretical average hold times are the same.

[0027] S22. Identify specific frequency points within the range of key frequency parameter variations that require extended action time.

[0028] In this step, specific frequency points within the range of difference frequency variation that require extended action time are identified, or specific frequency points within the range of difference frequency variation and frequency modulation variation that require extended action time are identified, so as to automatically detect special frequency points that require longer action time under the corresponding interference mode, and extract their number and required time.

[0029] Specifically, such as Figure 3 As shown, this step includes the following steps S221-S222: S221. Traverse each frequency point within the range of changes of the key frequency parameters and calculate the minimum required action time based on its frequency value.

[0030] In this step, if the key frequency parameter is the difference frequency, each frequency point within the difference frequency variation range is traversed, and the minimum required action time is calculated based on its frequency value. In this embodiment, the minimum required action time ti is calculated using the formula ti = 1000 / Fi, i∈[mn], where Fn and Fm represent the upper and lower limits of the difference frequency variation range, respectively, and Fi refers to any frequency point from Fm to Fn. Each frequency requires at least one complete cycle of action time to produce a physiological effect. The minimum action time ti represents the time required for the output current to complete one complete Fi frequency cycle. A lower time limit standard is established for each frequency point. The reciprocal of the frequency Fi is the time of a single cycle, with the unit being seconds (S). The time unit is converted to milliseconds (ms) using a unit conversion constant of 1000 to meet the high precision (millisecond level) requirements of medical devices for time control.

[0031] Accordingly, if the key frequency parameters are the synchronous difference frequency and modulation frequency, each frequency point within the difference frequency variation range and the modulation frequency variation range is traversed respectively, and the minimum required action time for each is calculated based on its frequency value. If the difference frequency variation range and the modulation frequency variation range are different, a suggested minimum action time for the difference frequency is generated for each difference frequency value in the difference frequency variation sequence. At the same time, a suggested minimum action time for the modulation frequency is generated for each modulation frequency value in the modulation frequency variation sequence. Since the difference frequency and the modulation frequency are synchronized, in order to ensure that both frequency components can reach the minimum effective action time, the larger of the suggested minimum action time for the difference frequency and the suggested minimum action time for the modulation frequency is taken as the minimum action time for the combined action of the pair of frequency values.

[0032] S222. Determine whether the minimum duration of action at the frequency point is greater than the theoretical average duration. If so, determine that the frequency point is a specific frequency point.

[0033] In this step, ti is iterated and compared with t0. If ti > t0, then the number of special frequency points num += 1, and the total time required for special frequency points t2 += ti.

[0034] S23. Assign a first holding time to the specific frequency point based on its frequency value, and recalculate the second average holding time of the remaining frequency points based on the change period and range of the key frequency parameters and the sum of the first holding times of all specific frequency points.

[0035] In this embodiment, the first holding time is the minimum action time at a specific frequency point.

[0036] In this step, the remaining time is redistributed, that is, the second average hold time of the remaining frequency points is calculated using the formula t = (T*1000 - t2) / (Fn - Fm + 1- num), where num represents the number of special frequency points.

[0037] Understandably, in practical applications, each time the differential frequency changes, it is necessary to calculate ti and compare it with t. If ti is greater than t, the differential frequency output is switched and adjusted after a timing period ti; otherwise, the differential frequency output is switched and adjusted only after a timing period t. If the differential frequency change method is constant, the differential frequency change range can be understood as 1 (i.e., m=n), and the differential frequency change period can be understood as the working time. If the differential frequency change method is random, it means that the differential frequency change period may be a random number time within 15-30 seconds, the differential frequency change range can be understood as 1 (i.e., m=n), and the differential frequency may be a random number frequency within 1-200Hz. After one differential frequency change period ends, the software system's random factor regenerates a differential frequency change period and differential frequency that conform to the range.

[0038] S30. Based on the currently determined key frequency parameters, generate a reference waveform signal.

[0039] Specifically, in this step, based on the key frequency parameters and the preset fundamental frequency and channel configuration relationship (e.g., channel A outputs the fundamental frequency, channel B outputs the fundamental frequency ± difference frequency), the waveform frequency of each output channel is calculated. Based on the calculated waveform frequencies of each channel, multiple reference waveform signals are generated, i.e., reference waveform signals corresponding to each output channel are generated. The difference frequency is switched according to its hold time, and the generated reference waveform signal will be maintained for output during the corresponding hold time.

[0040] If the key frequency parameter is the difference frequency, then based on the fundamental frequency and the currently determined difference frequency value, the waveform frequency of each channel is calculated according to the preset inter-channel frequency relationship; then, based on the calculated waveform frequency of each channel, multiple reference waveform signals are generated.

[0041] If the key frequency parameters include the difference frequency and the modulation frequency, then based on the fundamental frequency and the currently determined difference frequency value, and according to the preset inter-channel frequency relationship, the specific frequency to be output by each output channel is calculated, and the reference waveform signal of each channel is generated; wherein, the modulation frequency is used for subsequent envelope modulation and does not participate in the frequency generation of the reference waveform signal.

[0042] S40. During the holding time, the reference waveform signal is modulated and shaped to form the intermediate frequency interference current waveform signal required for treatment, and then output.

[0043] In this embodiment, the modulation and shaping of the reference waveform signal may include: sequentially performing intensity modulation and envelope modulation on the reference waveform signal. Specifically, intensity modulation may involve independently adjusting the amplitude of the reference waveform signal according to the intensity parameter in the waveform parameters to generate an amplitude-controlled intermediate signal; envelope modulation may involve generating an envelope control signal according to the envelope parameter corresponding to the current interference mode, and shaping the waveform shape of the intermediate signal.

[0044] In this step, the key frequency parameters are maintained throughout the entire calculated current hold-time window. The intensity and envelope modulation set according to the current treatment stage are continuously applied until the end of the current holding time is reached, and then the system switches to the next set of key frequency parameters and corresponding modulation shaping parameters.

[0045] Specifically, if the interference mode is a difference frequency interference electrical mode, this step specifically includes: during the holding time of each difference frequency, based on the intensity parameter and envelope parameter, sequentially performing intensity modulation and envelope modulation on the corresponding reference waveform signal to form an intermediate frequency interference current waveform signal. That is, during each holding time, based on the constant amplitude and envelope gain, intensity modulation and envelope modulation are performed on the corresponding reference waveform signal to form an intermediate frequency interference current signal, which is then output after constant current conversion. In this mode, the envelope parameter can be configured to apply a constant unity gain, that is, no specific envelope shaping is performed, and the shape is not changed, so that the envelope shape of the output waveform remains constant. The signal after envelope modulation is output after constant current conversion and applied to human tissue through the electrode of the selected channel. When the current holding time ends, the process immediately returns to step S20 to determine the next difference frequency value and its holding time, achieving dynamic switching with millisecond-level precision.

[0046] Understandably, in practical applications, after the envelope modulation is completed, the signal can be output to the selected output channels after constant current conversion. The frequency relationship of the output waveforms between channels is as follows: one channel directly outputs the fundamental frequency, and the other channels output the fundamental frequency ± the difference frequency by superimposing or subtracting the difference frequency.

[0047] If the interference mode is a vector interference electrical mode, this step specifically includes: during the holding time of each difference frequency, intensity modulation of the corresponding reference waveform signal according to the intensity parameter; generating a periodic trapezoidal wave envelope control signal according to the vector time and the number of output channels, and performing envelope modulation on the intensity-modulated waveform according to the trapezoidal wave envelope control signal to form an intermediate frequency interference current waveform signal with amplitude periodically changing according to a trapezoidal law. Specifically, the step of generating the periodic trapezoidal wave envelope control signal according to the vector time and the number of output channels includes: calculating the fixed period of the trapezoidal wave envelope according to the vector time and the number of activated output channels, and periodically calling a pre-stored trapezoidal wave amplitude array to generate the trapezoidal wave envelope control signal, wherein the total duration of a single trapezoidal wave period is equal to the product of the number of output channels and the vector time. In this mode, the difference frequency switches according to its holding time, while the trapezoidal wave envelope changes continuously according to its own period; the two work together to form an intermediate frequency interference current waveform signal with amplitude periodically changing according to a trapezoidal law.

[0048] If the interference mode is an amplitude-modulated interference electrical mode, this step specifically includes: within the holding time of each difference frequency, intensity modulation of the corresponding reference waveform signal according to the intensity parameter; generating an envelope modulation signal of the corresponding frequency according to the modulation frequency value corresponding to the current holding time; and performing envelope modulation on the intensity-modulated waveform according to the envelope modulation signal to form an interference current waveform signal whose amplitude is periodically modulated at the current modulation frequency; wherein, the change of the difference frequency is synchronized with the change of the modulation frequency and takes effect within the same holding time.

[0049] S50. During the output of the intermediate frequency interference current waveform signal, the actual current value of the output is sampled in real time. If the actual current value is lower than the preset safety threshold within a preset time period, it is determined that the output is open, triggering a safety alarm and stopping the output.

[0050] In this step, real-time sampling and feedback are performed during the output process to achieve closed-loop constant current control and open-circuit protection, ensuring treatment safety.

[0051] Understandably, when the intermediate frequency interference current output control method of this invention is applied to the use of an intermediate frequency electrotherapy device, if the user selects interference mode 1, the waveform parameters of this mode are first obtained, mainly including: fundamental frequency, difference frequency change mode (such as sweeping), and difference frequency change range [Fm, The system calculates the frequency difference value ΔF of the output waveform within the current output time period, based on the preset base frequency and the current frequency difference value ΔF. It then calculates the holding time of the frequency difference value using a holding time intelligent allocation algorithm, thereby calculating the first holding time at a specific frequency point and the second average holding time at other frequency points. Based on the preset base frequency and the current frequency difference value ΔF, it calculates the target frequency for each channel according to the channel-frequency relationship (e.g., channel A outputs the base frequency, channel B outputs the base frequency ± ΔF), and generates the reference waveform signal for each channel at the corresponding frequency. Finally, within the calculated current holding time, it performs intensity modulation (reaching the intensity parameter) and envelope modulation (usually configured as a constant unity-gain envelope, i.e., without changing the shape) on the reference waveform signal for each channel. The modulated signal is output after constant current conversion. When the current holding time ends, the system immediately returns to the previous steps of dynamically determining the frequency difference value ΔF of the output waveform within the current output time period and calculating the holding time of the frequency difference value using a holding time intelligent allocation algorithm, determining the next frequency difference value and its holding time, achieving dynamic switching with millisecond-level precision.

[0052] If the user selects interference mode 2, the waveform parameters for this mode are obtained. In addition to the difference frequency correlation parameters from mode 1, the vector time T_vector is also included to define the envelope rhythm. Then, the same process as in mode 1 is performed to dynamically determine the difference frequency value ΔF of the output waveform within the current output time period. The hold time of the difference frequency value is calculated using a hold time intelligent allocation algorithm to calculate the first hold time at specific frequency points and the second average hold time at other frequency points. Simultaneously, based on the vector time T_vector and the number of activated output channels, the fixed period T_cycle of the trapezoidal wave envelope is calculated. The system calculates the number of channels × T_vector and periodically calls the pre-stored trapezoidal waveform amplitude array to generate a continuous envelope control signal. Based on the preset fundamental frequency and the current difference frequency value ΔF, it calculates the target frequency of each channel according to the channel-frequency relationship (e.g., channel A outputs the fundamental frequency, channel B outputs the fundamental frequency ± ΔF) and generates the reference waveform signal for the corresponding frequency of each channel. During the holding time of the calculated current difference frequency, the reference waveform signal of each channel is intensity modulated, and the intensity-modulated signal is shaped according to the envelope control signal so that the amplitude of the final output waveform exhibits a periodic trapezoidal change of gradual increase, holding, and gradual decrease, ultimately forming a composite therapeutic current with dynamic frequency changes and amplitude fluctuations according to a fixed physiological rhythm.

[0053] If the user selects interference mode 3, the waveform parameters for this mode are obtained, including: fundamental frequency, difference frequency variation range, modulation frequency variation range, and the common variation method and variation period T. The variation ranges of the difference frequency and modulation frequency can be set independently or the same; if they are different, the difference frequency value ΔF of the output waveform within the current output time period is determined independently for the difference frequency sequence and the modulation frequency sequence, and the holding time of the difference frequency value is calculated through the holding time intelligent allocation algorithm. This process calculates the first holding time of the special frequency point and the second average holding time of the remaining frequency points (i.e., calculates their respective t0, ti, identifies their respective special frequency points and obtains t2_df). The system generates suggested hold times for all frequency values ​​in both sequences (t2_mod), and generates synchronized difference frequency and modulation frequency sequences based on the shared change pattern and period. For the i-th pair of synchronized values ​​(difference frequency value, modulation frequency value), it obtains their respective suggested hold times and takes the larger one as the minimum action time, i.e., the hold time, to ensure that both frequency components can obtain effective action time. Then, it calculates the channel frequency based on the current difference frequency value ΔF and the fundamental frequency to generate a reference waveform signal. The current modulation frequency value does not participate in the frequency generation of the reference waveform signal. Within the current hold time (minimum action time or second average hold time), the intensity of the reference signal is adjusted. The waveform is amplitude modulated using the current modulation frequency value as the frequency of the envelope modulation signal, so that the amplitude of the output current is regularly adjusted with the current modulation frequency value. When the current hold time ends, the system synchronously switches to the next pair of (difference frequency value, modulation frequency value) values ​​and their corresponding hold times, realizing complex interference treatment with dual dynamic changes in frequency and modulation depth.

[0054] As can be seen, in the above solution, this invention, through software configuration, can select an appropriate mode according to specific treatment needs, dynamically determine key frequency parameters based on the waveform parameters of the interference mode, and calculate its holding time. Unlike the fixed or simple loop output modes in existing technologies, this allows each frequency component to act on human tissue within its optimal duration, achieving millisecond-level high-precision timing control of the mid-frequency interference current. This avoids ineffective or excessive stimulation, resulting in more precise treatment output. Furthermore, the key frequency parameters of the output interference current can adapt to the input interference mode and its waveform parameters, making treatment flexible and configurable. During use, it can precisely change according to the waveform parameters (such as sweeping and other variations), demonstrating… This invention enhances the targeting and effectiveness of electrical stimulation on neuromuscular tissue, thereby further improving treatment efficacy. Furthermore, it allows for programmable intensity and envelope modulation of the reference waveform signal during the hold time, generating treatment waveforms with flexible and adjustable parameters and diverse morphologies. This provides flexible and configurable multi-mode treatment capabilities to adapt to diverse clinical needs. Combined with closed-loop output based on real-time sampling feedback, it also improves treatment safety. Therefore, this invention introduces configurable multi-mode treatment logic, combined with output control of key frequency parameters and hold time based on real-time algorithms, and integrated closed-loop feedback, improving the control precision, treatment flexibility, and safety of the mid-frequency electrotherapy device, thus meeting complex rehabilitation needs.

[0055] By reference Figure 4 , Figure 4 The intermediate frequency interference current output control system provided in this embodiment of the invention is applied to an intermediate frequency electrotherapy device to execute the intermediate frequency interference current output control method described in the above embodiment. In the embodiment shown in the accompanying drawings, the intermediate frequency interference current output control system includes a main control unit 101, a base frequency control unit 102, a modulation output unit 103, and a sampling feedback unit 104. Detailed descriptions of each functional module are as follows: The main control unit 101 is used to acquire the interference mode input to the intermediate frequency electrotherapy device and acquire the waveform parameters corresponding to the interference mode; and based on the waveform parameters, dynamically determine the key frequency parameters of the output waveform within the current output time period, calculate the holding time of the key frequency parameters; and calculate the waveform frequency of each output channel based on the currently determined key frequency parameters. The main control unit 101, as the core of the system, preferably uses a high-performance ARM Cortex-M series microcontroller, responsible for running the control logic and calculations in the above-mentioned intermediate frequency interference current output control method, and can be connected to and controlled by peripheral units via an independent SPI communication bus. In this embodiment, the interference modes include interference mode 1, interference mode 2, and interference mode 3. Interference mode 1, interference mode 2, and interference mode 3 can be differential frequency interference electrical mode, vector interference electrical mode, and amplitude modulation interference electrical mode, respectively. If the interference mode is interference mode 3 and the change method is sweep, then two threads are started to continuously calculate the hold time of each differential frequency and the hold time of each modulation frequency using the hold time calculation method. At the same time, the differential frequency and the adjustment frequency are adjusted. When adjusting the differential frequency, the reference waveform signal frequency of each output channel is calculated according to the selected output channel and the relationship between the output frequencies of the channels. One channel directly outputs the base frequency, and the other channels output the base frequency ± the differential frequency frequency by superimposing or subtracting the differential frequency. The output frequency of each channel is sent to the base frequency control unit 102 using the combination of SPI bus and chip select, driving it to immediately generate a reference waveform with a specified frequency. At the same time, the main control unit 101 starts a timer corresponding to the hold time. Within this hold time range, the system will maintain the constant output frequency of this reference waveform signal until the timer ends, triggering the parameter determination and signal generation of the next cycle.

[0056] The baseband control unit 102, connected to the main control unit 101, is used to generate corresponding reference waveform signals based on the waveform frequencies of each output channel. In this embodiment, the baseband control unit 102 can be composed of multiple high-precision direct digital synthesizer (DDS) chips, such as the AD9833. Specifically, the reference waveform signal generation is achieved based on multiple DDS chips. One DDS chip is connected to one output channel and can receive frequency control words sent by the main control unit 101 via an SPI bus to generate the required frequency and waveform reference waveform signal. Based on the above design, this invention uses a single main control unit 101 combined with a high-precision direct digital synthesizer (DDS) as the reference signal source. The reference waveform signals of all output channels are calculated and uniformly driven by the same main control unit 101 in real time according to a preset algorithm. This ensures strict frequency relationships and phase consistency between multiple signals from the source, eliminates frequency drift, and ensures the homogeneity and long-term synchronization stability of multiple output signals from a hardware architecture perspective.

[0057] A modulation output unit 103, connected to the baseband control unit 102, is used to independently modulate and shape the reference waveform signal during the holding time to form a mid-frequency interference current waveform signal required for treatment, and then output it. Specifically, in some embodiments, the modulation output unit 103 includes an intensity control unit 1031, an envelope modulation unit 1032, and a constant current output unit 1033. The intensity control unit 1031 is connected to the baseband control unit 102 and is used to perform amplitude modulation on the reference waveform signal. Preferably, it can be composed of a multi-channel digital potentiometer chip (such as AD5204), which can receive intensity control data sent by the main control unit 101 via an SPI bus, and perform precise amplitude attenuation or amplification on the reference waveform signal sent by the DDS to realize independent digital control of the intensity of each channel, so as to realize amplitude modulation separately. The envelope modulation unit 1032 is connected to the intensity control unit 1031. The envelope modulation unit 1032 is used to perform envelope shaping on the modulated waveform. It can also be composed of a multi-channel digital potentiometer chip, receiving envelope control data (such as a trapezoidal wave amplitude array or modulation frequency) generated by the main control unit 101 according to the current interference mode via an SPI bus. This data is used to perform envelope shaping on the intensity-modulated signal to simulate physiological stimulation effects. The constant current output unit 1033 is connected to the envelope modulation unit 1032 and is used to convert the shaped signal into a constant current output. It can include multiple independent voltage-to-current conversion circuits to receive multiple analog voltage signals output by the envelope modulation unit 1032 and convert them into a constant, safe current output to the electrodes.

[0058] The sampling feedback unit 104, connected to the constant current output unit 1033 and the main control unit 101, is used to sample the output current in real time and feed it back to the main control unit 101. This allows the main control unit 101 to determine whether there is an open circuit based on the sampled output current within a preset time period and a preset safety threshold. If an open circuit occurs, an alarm is triggered and the output is stopped. Preferably, a high-precision sampling resistor and a differential amplification sampling circuit can be used to sample the output current of each channel in real time and feed the sampling signal back to the main control unit 101. The main control unit 101 can compare the sampled output current with the preset safety threshold to achieve closed-loop constant current control and open circuit protection (e.g., if the current is too low for 6 consecutive seconds, it is judged as an open circuit alarm), ensuring treatment safety.

[0059] Understandably, in this embodiment, the main control unit 101 independently controls the baseband control unit 102, the intensity control unit 1031, and the envelope modulation unit 1032 via three SPI buses. The reference signal waveform output by the baseband control unit 102 is sent in parallel to the intensity control unit 1031. The signal modulated by the intensity control unit 1031 is then sent to the envelope modulation unit 1032. The final multi-channel analog signals output by the envelope modulation unit 1032 are sent to the corresponding channels of the constant current output unit 1033. The constant current output unit 1033 outputs to each selected or default output channel. The sampling feedback unit 104 is connected between each output channel and the main control unit 101 for sampling feedback to achieve protection.

[0060] As can be seen, through the above technical solution, this invention achieves intelligent, millisecond-level high-precision timing control and multi-mode control of mid-frequency interference current output. It can flexibly configure the difference frequency change law and superimpose different types of envelopes according to different treatment needs, generating treatment waveforms with flexible adjustable parameters and diverse forms, providing a variety of essentially different treatment waveforms and stimulation modes, greatly enriching the treatment methods of electrical stimulation, adapting to diverse clinical needs, significantly improving the current output control accuracy and dynamic adaptability, while realizing the personalization and diversification of treatment modes, thereby effectively enhancing the targeting, safety and overall treatment effect of mid-frequency interference electrotherapy, and further improving treatment safety by combining real-time sampling feedback closed-loop output.

[0061] It should be noted that the specific limitations regarding the intermediate frequency interference current output control system can be found in the limitations of the intermediate frequency interference current output control method mentioned above, and will not be repeated here. Those skilled in the art will understand that, for the sake of convenience and brevity, the above division of units and components is used as an example. In practical applications, the above functions can be assigned to different units and modules as needed.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Those skilled in the art can make various equivalent changes and improvements based on the above embodiments, and all equivalent variations or modifications made within the scope of the claims should fall within the protection scope of the present invention.

Claims

1. A method for controlling the output of intermediate frequency interference current, characterized in that, include: Obtain the interference pattern, and obtain the corresponding waveform parameters based on the interference pattern; Based on the waveform parameters, the key frequency parameters of the output waveform within the current output time period are dynamically determined, and the holding time of the key frequency parameters is calculated. Based on the currently determined key frequency parameters, a reference waveform signal is generated; During the holding time, the reference waveform signal is modulated and shaped to form the intermediate frequency interference current waveform signal required for treatment, and then output.

2. The intermediate frequency interference current output control method as described in claim 1, characterized in that, If the key frequency parameter includes a difference frequency, or includes both a difference frequency and a modulation frequency; wherein, calculating the hold time of the key frequency parameter specifically includes: Based on the variation period and range of the key frequency parameters in the waveform parameters, the theoretical average hold time is calculated. Identify specific frequency points within the range of key frequency parameter variations that require extended action time; A first hold time, calculated based on the frequency value, is assigned to the specific frequency point, and a second average hold time is recalculated based on the change period and range of the key frequency parameters and the sum of the first hold times of all specific frequency points.

3. The intermediate frequency interference current output control method as described in claim 2, characterized in that, The specific frequency points requiring extended action time within the range of key frequency parameter variations include: Iterate through each frequency point within the range of changes in the key frequency parameters and calculate the minimum required action time based on its frequency value; Determine whether the minimum duration of action at the frequency point is greater than the theoretical average duration. If so, determine that the frequency point is a specific frequency point.

4. The intermediate frequency interference current output control method as described in claim 1 or 2, characterized in that, The interference mode includes a vector interference electrical mode, and the waveform parameters include at least the fundamental frequency, difference frequency, vector time, difference frequency variation mode, difference frequency variation range, difference frequency variation period, intensity parameter, and envelope parameter; the key frequency parameter is the difference frequency; wherein... During the holding time, the reference waveform signal is modulated and shaped to form the intermediate frequency interference current waveform signal required for treatment, and then output, specifically including: During the holding time of each difference frequency, the corresponding reference waveform signal is intensity modulated according to the intensity parameter; Based on the vector time and the number of output channels, a periodic trapezoidal wave envelope control signal is generated, and the waveform after intensity modulation is envelope modulated according to the trapezoidal wave envelope control signal to form a medium-frequency interference current waveform signal whose amplitude changes periodically according to a trapezoidal law, and then output after constant current conversion.

5. The intermediate frequency interference current output control method as described in claim 1 or 2, characterized in that, The interference mode includes an amplitude-modulated interference electrical mode, and the waveform parameters include at least the fundamental frequency, difference frequency, modulation frequency, difference frequency / frequency modulation variation mode, difference frequency / frequency modulation variation range, difference frequency / frequency modulation variation period, intensity parameter, and envelope parameter; the key frequency parameters include the difference frequency and the modulation frequency; wherein... During the holding time, the reference waveform signal is modulated and shaped to form the intermediate frequency interference current waveform signal required for treatment, and then output, specifically including: During the holding time of each difference frequency, the corresponding reference waveform signal is intensity modulated according to the intensity parameter; Based on the modulation frequency value corresponding to the current holding time, an envelope modulation signal of the corresponding frequency is generated. The waveform after intensity modulation is envelope modulated according to the envelope modulation signal, thereby forming an interference current waveform signal whose amplitude is periodically modulated at the current modulation frequency, and output after constant current conversion. The change in the difference frequency is synchronized with the change in the modulation frequency and takes effect within the same holding time.

6. The intermediate frequency interference current output control method as described in claim 1 or 2, characterized in that, The interference mode includes a difference frequency interference electrical mode, and the waveform parameters include at least the fundamental frequency, difference frequency, difference frequency variation mode, difference frequency variation range, difference frequency variation period, intensity parameter, and envelope parameter; the key frequency parameter is the difference frequency; wherein... During the holding time, the reference waveform signal is modulated and shaped to form the intermediate frequency interference current waveform signal required for treatment, and then output, specifically including: During the holding time of each difference frequency, based on the intensity parameter and envelope parameter, the corresponding reference waveform signal is sequentially subjected to intensity modulation and envelope modulation to form an intermediate frequency interference current waveform signal, which is then output after constant current conversion.

7. The intermediate frequency interference current output control method as described in claim 1, characterized in that, The intermediate frequency interference current output control method further includes: During the output of the intermediate frequency interference current waveform signal, the actual current value of the output is sampled in real time. If the actual current value is lower than the preset safety threshold within a preset time period, it is determined that the output is open circuit, triggering a safety alarm and stopping the output.

8. A medium-frequency interference current output control system, characterized in that, The intermediate frequency interference current output control system includes: The main control unit is used to acquire the interference mode input to the intermediate frequency electrotherapy device and acquire the waveform parameters corresponding to the interference mode; and based on the waveform parameters, dynamically determine the key frequency parameters of the output waveform within the current output time period, calculate the holding time of the key frequency parameters; and calculate the waveform frequency of each output channel based on the currently determined key frequency parameters. The base frequency control unit, connected to the main control unit, is used to generate corresponding reference waveform signals based on the waveform frequency of each output channel; A modulation output unit, connected to the baseband control unit, is used to independently modulate and shape the reference waveform signal during the holding time to form the intermediate frequency interference current waveform signal required for treatment, and then output it.

9. The intermediate frequency interference current output control system as described in claim 8, characterized in that, The modulation output unit includes: An intensity control unit, connected to the baseband control unit, is used to perform amplitude modulation on the reference waveform signal; An envelope modulation unit, connected to the intensity control unit, is used to perform envelope shaping on the modulated waveform; A constant current output unit, connected to the envelope modulation unit, is used to convert the shaped signal into a constant current output.

10. The intermediate frequency interference current output control system as described in claim 9, characterized in that, The intermediate frequency interference current output control system also includes: The sampling feedback unit is connected to the constant current output unit and the main control unit. It is used to sample the output current in real time and feed it back to the main control unit so that the main control unit can determine whether there is an open circuit based on the output current sampled within a preset time period and a preset safety threshold, and trigger an alarm and stop the output when there is an open circuit.

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