Control Circuit of a Multi-Mode Electrotherapy Apparatus

Abstract

The present invention discloses a control circuit for a multi-mode electrotherapy instrument, which includes a power supply (1) and an electrode plate group (7). The power supply (1) is connected to a voltage stabilization control circuit (2) and a low-voltage inverter circuit (3). An output side of the low-voltage inverter circuit (3) is provided with a boost circuit (4). An output end of the boost circuit (4) is connected to a multi-way on-off inverter circuit (5). An output end of the multi-way on-off inverter circuit (5) is connected to a high-voltage shaping circuit (6). The voltage stabilization control circuit (2) is respectively connected to the power supply (1), the low-voltage inverter circuit (3), the multi-way on-off inverter circuit (5) and the high-voltage shaping circuit (6). By means of circuit on-off combination, the present invention provides voltages of multiple waveforms, can generate multiple physical therapy voltage sections, and has the characteristics of flexible use, wide adjustment range and fast control. In addition, the present invention also has multiple voltage stabilization protections, improving the safety in use.

Description

Technical Field

[0001] The present invention relates to the field of electrotherapy apparatuses, and particularly to a control circuit for a multi-mode electrotherapy apparatus. Background Art

[0002] Laborers engaged in heavy physical labor and athletes in high-intensity sports training are often tortured by chronic pain such as muscle strain, rheumatism, rheumatoid arthritis, and intervertebral discs, causing serious pain to people's physiology and psychology. The treatment of the above diseases can be divided into drug therapy and physical therapy. Drug treatment mainly relies on analgesic drugs to relieve pain, but it is prone to the side effect of drug resistance; physical therapy has a good therapeutic effect on the above diseases and has been proven to be a method with obvious effect in relieving soft tissue injuries; among them, electrophysical therapy is a commonly used physiotherapy method now. For example, electro-acupuncture, electrotherapy apparatuses, etc. can effectively relieve the above symptoms; currently, medium-frequency alternating current electrotherapy apparatuses are widely used in clinics, which mainly generate a medium-frequency alternating current constant current source to act on the affected area, thereby achieving the therapeutic effect. Chinese Patent with Application No. 202111491582.4 discloses a constant current type modulated medium-frequency electrotherapy apparatus circuit and its working principle, which can realize any combination and arbitrary adjustment of continuous modulation, intermittent modulation, discontinuous modulation, and variable modulation of sine waves, triangular waves, and square waves, and can avoid the adaptability of the human body caused by the current of a single frequency and a single waveform. This solution is realized by using the DDS method, and the waveforms it can control rely on pre-configured waveform data, with certain band limitations and limited adjustment ranges; in addition, this application adopts a current source scheme, and the output current is as high as 100 mA. When using the current source scheme, there is no overvoltage protection. Due to the different constitutions of the human body and the placement positions of the electrotherapy apparatus, the resistance change range is very large, even up to dozens of megohms. At this time, even a current of only 0.1 mA may generate hundreds of volts of voltage, with certain potential safety hazards and poor safety. Summary of the Invention

[0003] The purpose of the present invention is to provide a control circuit for a multi-mode electrotherapy apparatus. The present invention provides voltages of multiple waveforms through the combination of circuit on-off, can generate multiple physiotherapy voltage sections, and has the characteristics of flexible use, wide adjustment range, and fast control; in addition, the present invention also has multiple voltage stabilization protections, improving the safety of use.

[0004] The technical solution provided by the present invention is as follows: A control circuit for a multi-mode electrotherapy instrument, including a power supply and an electrode plate group, the power supply is connected with a voltage stabilization control circuit and a low-voltage inverter circuit; an output side of the low-voltage inverter circuit is provided with a boost circuit, an output end of the boost circuit is connected with a multi-way on-off inverter circuit, and an output end of the multi-way on-off inverter circuit is connected with a high-voltage shaping circuit; the voltage stabilization control circuit is respectively connected with the power supply, the low-voltage inverter circuit, the multi-way on-off inverter circuit and the high-voltage shaping circuit; the voltage stabilization control circuit is used for obtaining the voltage and current of the power supply, and calculating control signals corresponding to the low-voltage inverter circuit, the multi-way on-off inverter circuit and the high-voltage shaping circuit according to the voltage and current of the power supply; after receiving the corresponding control signal, the low-voltage inverter circuit performs an inverter with a controllable output value on the voltage of the power supply and outputs an alternating voltage; the boost circuit boosts the alternating voltage of the low-voltage inverter circuit and outputs a boosted voltage; after receiving the corresponding control signal, the multi-way on-off inverter circuit performs an inverter and waveform control on the boosted voltage of the boost circuit through a combination of multiple circuit on-offs and outputs a waveform voltage; after receiving the corresponding control signal, the high-voltage shaping circuit shapes the waveform voltage of the multi-way on-off inverter circuit and performs waveform switching through circuit on-off, and finally outputs it to the electrode plate group; thus, through the waveform control of the multi-way on-off inverter circuit and the waveform switching of the high-voltage shaping circuit, the electrotherapy instrument generates physiotherapy voltages of multiple waveforms.

[0005] In the control circuit of the multi-mode electrotherapy instrument described above, the low-voltage inverter circuit includes NMOS transistor Q1, NMOS transistor Q2, NMOS transistor Q3, NMOS transistor Q4 and boost transformer T1; a drain of the NMOS transistor Q1 is connected to a positive electrode of the power supply and a drain of the NMOS transistor Q2, a source of the NMOS transistor Q2 is connected to a drain of the NMOS transistor Q4, a source of the NMOS transistor Q1 is connected to a drain of the NMOS transistor Q3, and a source of the NMOS transistor Q3 is connected to a source of the NMOS transistor Q4 and a negative electrode of the power supply; one end of an input side of the boost transformer T1 is connected to a source of the NMOS transistor Q1 and a drain of the NMOS transistor Q3, and the other end of the input side of the boost transformer T1 is connected to a source of the NMOS transistor Q2 and a drain of the NMOS transistor Q4; a gate and a drain of the NMOS transistor Q1, a gate and a drain of the NMOS transistor Q2, a gate of the NMOS transistor Q3 and a gate of the NMOS transistor Q4 are connected to the voltage stabilization control circuit; an output side of the boost transformer T1 is connected to the boost circuit.

[0006] In the control circuit of the multi-mode electrotherapy instrument described above, the boost circuit includes capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, capacitor C9, capacitor C 10 、capacitor C 11, diodes D1, D2, D3, D4, D5, D6, D7, D8, D9, diode D 10 and diode D 11 ; One end of the capacitor C1 is connected to one pole of the output terminal of the low-voltage inverter circuit, and the other end of the capacitor C1 is successively connected in series with capacitors C3, C5, C7, C9 and capacitor C 11 to form a first charging circuit. One end of the capacitor C2 is connected to the other pole of the output terminal of the low-voltage inverter circuit, and the other end of the capacitor C2 is successively connected in series with capacitors C4, C6, C8 and capacitor C 10 to form a second charging circuit; The end of the first charging circuit is connected to the multi-way on-off inverter circuit; The diodes D1, D2, D3, D4, D5, D6, D7, D8, D9, diode D 10 and diode D 11 are connected between the first charging circuit and the second charging circuit in the form of a voltage multiplier circuit.

[0007] In the control circuit of the aforementioned multi-mode electrotherapy instrument, the multi-way on-off inverter circuit includes resistors R3, R4, R5, R6, R7, R8, R9, resistor R 10 , resistor R 11 , resistor R 12 , resistor R 13 , resistor R 14, high-voltage optocoupler OP1, high-voltage optocoupler OP2, high-voltage optocoupler OP3, high-voltage optocoupler OP4, P IGBT transistor Q5, N IGBT transistor Q6, P IGBT transistor Q7, N IGBT transistor Q8 and step-up transformer T2; The emitter of the P IGBT transistor Q5 is connected to the output end of the boost circuit and one end of the resistor R3, the collector of the P IGBT transistor Q5 is connected to the collector of the N IGBT transistor Q6 and one pole of the input side of the step-up transformer T2, and the gate of the P IGBT transistor Q5 is connected to the other end of the resistor R3 and the C pole of the high-voltage optocoupler OP1. The E pole of the high-voltage optocoupler OP1 is connected to the weak-current circuit through the resistor R5, and the negative pole of the high-voltage optocoupler OP1 is grounded; The emitter of the N IGBT transistor Q6 is grounded, and the gate of the N IGBT transistor Q6 is connected to one end of the resistor R6, one end of the resistor R7 and the C pole of the high-voltage optocoupler OP2. The other end of the resistor R6 is connected to the output end of the boost circuit. The E pole of the high-voltage optocoupler OP2 is connected to the other end of the resistor R7 and grounded, and the positive pole of the high-voltage optocoupler OP2 is connected to the power supply voltage; The emitter of the P IGBT transistor Q7 is connected to the output end of the boost circuit and one end of the resistor R9, the collector of the P IGBT transistor Q7 is connected to the collector of the N IGBT transistor Q8 and the other pole of the input side of the step-up transformer T2, and the gate of the P IGBT transistor Q7 is connected to the other end of the resistor R9 and the C pole of the high-voltage optocoupler OP3. The E pole of the high-voltage optocoupler OP3 is connected to the weak-current circuit through the resistor R 11 connected to the weak-current circuit, and the negative pole of the high-voltage optocoupler OP1 is grounded; The emitter of the N IGBT transistor Q8 is grounded, and the gate of the N IGBT transistor Q8 is connected to one end of the resistor R 12 and one end of the resistor R 13 and the C pole of the high-voltage optocoupler OP4. The other end of the resistor R 12 is connected to the output end of the boost circuit. The E pole of the high-voltage optocoupler OP4 is connected to the other end of the resistor R 13 and grounded, and the positive pole of the high-voltage optocoupler OP4 is connected to the power supply voltage; The positive pole of the high-voltage optocoupler OP1 is connected to one end of the resistor R4, the negative pole of the high-voltage optocoupler OP2 is connected to one end of the resistor R8, the positive pole of the high-voltage optocoupler OP3 is connected to one end of the resistor R 10 and the negative pole of the high-voltage optocoupler OP4 is connected to one end of the resistor R 14 . The other end of the resistor R4, the other end of the resistor R8, the other end of the resistor R 10 and the other end of the resistor R 14 are connected to the output end of the voltage stabilization control circuit; The output side of the step-up transformer T2 is connected to the high-voltage shaping circuit.

[0008] In the control circuit of the aforementioned multi-mode electrotherapy instrument, the high-voltage shaping circuit includes a resistor R 15 , a capacitor C 12 and a relay KA. One end of the resistor R 15 is connected to one pole of the output end of the multi-way on-off inverter circuit, and one end of the resistor R 15The other end is connected to one pole piece of the pole piece group and the capacitor C. 12 One end of the capacitor C 12 The other end is connected to the other pole piece of the pole piece group and the other pole of the output end of the multi-way on-off inverter circuit; the relay KA and the resistor R 15 Are in parallel, and the control end of the relay KA is connected to the output end of the voltage stabilization control circuit.

[0009] In the control circuit of the aforementioned multi-mode electrotherapy instrument, the voltage stabilization control circuit includes an MCU, a shunt resistor R sh , resistor R cf , resistor R1, resistor R2, capacitor C cf , capacitor C vf And a voltage stabilization module. The power supply end of the MCU is connected to the power supply voltage through the voltage stabilization module; the shunt resistor R sh Is connected to the power supply voltage, and one end of the resistor R cf Is connected to one end of the shunt resistor R sh , and the other end of the resistor R cf Is connected to one end of the capacitor C cf And the sampling end AD1 of the MCU. The other end of the capacitor C cf Is connected to the other end of the shunt resistor R sh ; One end of the resistor R1 is connected to the power supply voltage, the other end of the resistor R1 is connected to one end of the resistor R2, one end of the capacitor C vf And the sampling end AD2 of the MCU. The other end of the resistor R2 is connected to the other end of the capacitor C vf ; The signal output end of the MCU is connected to the low-voltage inverter circuit, the multi-way on-off inverter circuit and the high-voltage shaping circuit.

[0010] Compared with the prior art, in the present invention, the power supply voltage is converted into an AC voltage within a certain range through the low-voltage inverter circuit. After the AC voltage is boosted by the boost circuit, it is further inverted and waveform-controlled by the multi-way on-off inverter circuit. The waveform voltage of the multi-way on-off inverter circuit is finally output to the pole piece group after being shaped and waveform-switched by the high-voltage shaping circuit. Multiple waveforms of voltage are provided through the waveform control of the multi-way on-off inverter circuit and the waveform switching of the high-voltage shaping circuit; compared with the DSS method, a high-voltage shaping circuit is creatively set up for shaping and waveform switching, and more waveforms can be realized by further combining on the basis of the original waveforms, which has the characteristics of flexible use, wide adjustment range and fast control; in addition, the present invention provides multiple voltage stabilization protections for the voltage through the voltage stabilization control circuit and the low-voltage inverter circuit, improving the safety of use. Brief Description of the Drawings

[0011] Figure 1 It is a circuit schematic diagram of the present invention;

[0012] Figure 2This is the modulation schematic diagram of the symmetric AC triangular wave of the present invention;

[0013] Figure 3 This is the modulation schematic diagram of the unipolar triangular wave of the present invention;

[0014] Figure 4 This is the modulation schematic diagram of the square wave of the present invention;

[0015] Figure 5 This is the modulation principle of the sine wave of the present invention.

[0016] The reference numerals in the drawings are: 1, power supply; 2, voltage stabilization control circuit; 3, low-voltage inverter circuit; 4, boost circuit; 5, multi-way on-off inverter; 6, high-voltage shaping circuit; 7, electrode plate group; 8, voltage stabilization module. Specific embodiments

[0017] The present invention will be further described below in conjunction with the embodiments and the drawings, but it shall not be used as the basis for limiting the present invention.

[0018] Embodiment: A control circuit of a multi-mode electrotherapy instrument, as shown in the attached Figure 1 figure, includes a power supply 1 and an electrode plate group 7 that outputs V E . The power supply 1 is connected to a voltage stabilization control circuit 2 and a low-voltage inverter circuit 3; a boost circuit 4 is arranged on the output side of the low-voltage inverter circuit 3, the output end of the boost circuit 4 is connected to a multi-way on-off inverter circuit 5, and the output end of the multi-way on-off inverter circuit 5 is connected to a high-voltage shaping circuit 6; the voltage stabilization control circuit 2 is respectively connected to the power supply 1, the low-voltage inverter circuit 3, the multi-way on-off inverter circuit 5 and the high-voltage shaping circuit 6; the voltage stabilization control circuit 2 is used to obtain the voltage and current of the power supply 1, and calculate the corresponding control signals of the low-voltage inverter circuit 3, the multi-way on-off inverter circuit 5 and the high-voltage shaping circuit 6 according to the voltage and current of the power supply 1; after receiving the corresponding control signals, the low-voltage inverter circuit 3 performs an inversion with a controllable output value on the voltage of the power supply 1 and outputs an AC voltage; the boost circuit 4 boosts the AC voltage of the low-voltage inverter circuit 3 and outputs a boosted voltage; after receiving the corresponding control signals, the multi-way on-off inverter circuit 5 performs inversion and waveform control on the boosted voltage of the boost circuit 4 through the combination of multi-circuit on-off and outputs a waveform voltage; after receiving the corresponding control signals, the high-voltage shaping circuit 6 shapes the waveform voltage of the multi-way on-off inverter circuit 5 and performs waveform switching through circuit on-off, and finally outputs it to the electrode plate group 7; thus, through the waveform control of the multi-way on-off inverter circuit and the waveform switching of the high-voltage shaping circuit, the electrotherapy instrument generates physiotherapy voltages of multiple waveforms.

[0019] The low-voltage inverter circuit includes NMOS transistors Q1, Q2, Q3, Q4 and a boost transformer T1 with a turns ratio of 1:N1; the drain of NMOS transistor Q1 is connected to the positive power supply and the drain of NMOS transistor Q2, the source of NMOS transistor Q2 is connected to the drain of NMOS transistor Q4, the source of NMOS transistor Q1 is connected to the drain of NMOS transistor Q3, and the source of NMOS transistor Q3 is connected to the source of NMOS transistor Q4 and the negative power supply; one end of the input side of the boost transformer T1 is connected to the source of NMOS transistor Q1 and the drain of NMOS transistor Q3, and the other end of the input side of the boost transformer T1 is connected to the source of NMOS transistor Q2 and the drain of NMOS transistor Q4, forming an H-bridge inverter circuit; the gates and drains of NMOS transistor Q1, NMOS transistor Q2, NMOS transistor Q3 and the gate of NMOS transistor Q4 are connected to a voltage stabilization control circuit; the output side of the boost transformer T1 is connected to a boost circuit; the boost transformer T1 realizes voltage boost and isolation for energy transfer, and the H-bridge inverter circuit converts the low-voltage DC power supply V E into an alternating current with a higher voltage. The PWM port signals H1, H2, PWM1 and PWM2 of the MCU in the voltage stabilization control circuit are respectively connected to the gates of NMOS transistor Q1, NMOS transistor Q2, NMOS transistor Q3 and NMOS transistor Q4. The COM1 and COM2 ports of the MCU are respectively connected to the drains of NMOS transistor Q1 and NMOS transistor Q2. H1, COM1 and H2, COM2 contain voltage boost circuits to meet the drive voltage requirements of the upper NMOS transistors Q1 and Q2. The MCU realizes the regulation of the output voltage and output energy of the entire circuit by adjusting the duty cycle of the drive signals of NMOS transistor Q1, NMOS transistor Q2, NMOS transistor Q3 and NMOS transistor Q4, ensuring that the output voltage and output energy of the physiotherapy device are within a safe range.

[0020] The boost circuit includes capacitors C1, C2, C3, C4, C5, C6, C7, C8, C9, capacitor C 10 , capacitor C 11 , diodes D1, D2, D3, D4, D5, D6, D7, D8, D9, diode D 10 and diode D 11 ; one end of capacitor C1 is connected to one pole of the output end of the low-voltage inverter circuit, and the other end of capacitor C1 is sequentially connected in series with capacitors C3, C5, C7, C9 and capacitor C 11 to form a first charging loop. One end of capacitor C2 is connected to the other pole of the output end of the low-voltage inverter circuit, and the other end of capacitor C2 is sequentially connected in series with capacitors C4, C6, C8 and capacitor C 10Form the second charging circuit; the end of the first charging circuit is connected to the multi-way on-off inverter circuit; the diodes D1, D2, D3, D4, D5, D6, D7, D8, D9, diode D 10 and diode D 11 Are connected between the first charging circuit and the second charging circuit in the form of a voltage multiplier circuit to realize the functions of rectification and boosting. According to electrical engineering knowledge, capacitor C2 - capacitor C 11 The voltage of each capacitor is twice the voltage of capacitor C1. Therefore, the voltages of capacitor C3, capacitor C5, capacitor C7, capacitor C9 and capacitor C 11 The voltages of the five series-connected capacitors are equal to the voltages of capacitor C2, capacitor C4, capacitor C6, capacitor C8 and capacitor C 10 The voltages of the five series-connected capacitors are equal and are 10 times the voltage of capacitor C1. The voltage multiplication method reduces the voltage and current stress, volume and cost of the boost transformer T1; if higher boost is desired, only a few more boost units need to be added.

[0021] The multi-way on-off inverter circuit includes resistors R3, R4, R5, R6, R7, R8, R9, resistor R 10 , resistor R 11 , resistor R 12 , resistor R 13 , resistor R 14 , high-voltage optocoupler OP1, high-voltage optocoupler OP2, high-voltage optocoupler OP3, high-voltage optocoupler OP4, PIGBT transistor Q5, NIGBT transistor Q6, PIGBT transistor Q7, NIGBT transistor Q8 and a boost transformer T2 with a turn ratio of 1:N2; the emitter of the PIGBT transistor Q5 is connected to the output end of the boost circuit and one end of the resistor R3, the collector of the PIGBT transistor Q5 is connected to the collector of the NIGBT transistor Q6 and one pole of the input side of the boost transformer T2, the gate of the PIGBT transistor Q5 is connected to the other end of the resistor R3 and the C pole of the high-voltage optocoupler OP1, the E pole of the high-voltage optocoupler OP1 is connected to the weak-current circuit through the resistor R5, and the negative pole of the high-voltage optocoupler OP1 is grounded; the emitter of the NIGBT transistor Q6 is grounded, the gate of the NIGBT transistor Q6 is connected to one end of the resistor R6, one end of the resistor R7 and the C pole of the high-voltage optocoupler OP2, the other end of the resistor R6 is connected to the output end of the boost circuit, the E pole of the high-voltage optocoupler OP2 is connected to the other end of the resistor R7 and grounded, and the positive pole of the high-voltage optocoupler OP2 is connected to the power supply voltage; the emitter of the PIGBT transistor Q7 is connected to the output end of the boost circuit and one end of the resistor R9, the collector of the PIGBT transistor Q7 is connected to the collector of the NIGBT transistor Q8 and the other pole of the input side of the boost transformer T2, the gate of the PIGBT transistor Q7 is connected to the other end of the resistor R9 and the C pole of the high-voltage optocoupler OP3, the E pole of the high-voltage optocoupler OP3 is connected through the resistor R11 Connect the weak current circuit, and the negative electrode of the high-voltage optocoupler OP1 is grounded; the emitter of the NIGBT transistor Q8 is grounded, and the gate of the NIGBT transistor Q8 is connected to one end of the resistor R 12 and one end of the resistor R 13 and the C pole of the high-voltage optocoupler OP4. The other end of the resistor R 12 is connected to the output end of the boost circuit, and the E pole of the high-voltage optocoupler OP4 is connected to the other end of the resistor R 13 and is grounded. The positive electrode of the high-voltage optocoupler OP4 is connected to the power supply voltage; the positive electrode of the high-voltage optocoupler OP1 is connected to one end of the resistor R4, the negative electrode of the high-voltage optocoupler OP2 is connected to one end of the resistor R8, the positive electrode of the high-voltage optocoupler OP3 is connected to one end of the resistor R 10 and the negative electrode of the high-voltage optocoupler OP4 is connected to one end of the resistor R 14 and the other end of the resistor R4, the other end of the resistor R8, the other end of the resistor R 10 and the other end of the resistor R 14 are connected to the output end of the voltage stabilization control circuit; the output side of the boost transformer T2 is connected to the high-voltage shaping circuit; the resistor R3, the resistor R4, the resistor R5 and the high-voltage optocoupler OP1 form a driving circuit for the PIGBT transistor Q5, and the Drive1 of the MCU in the voltage stabilization control circuit drives and controls the on-off of the PIGBT transistor Q5; the resistor R6, the resistor R7, the resistor R8 and the high-voltage optocoupler OP2 form a driving circuit for the NIGBT transistor Q6, and the Drive2 of the MCU drives and controls the on-off of the NIGBT transistor Q6; the resistor R9, the resistor R 10 and the resistor R 11 and the high-voltage optocoupler OP3 form a driving circuit for the PIGBT transistor Q7, and the Drive3 of the MCU drives and controls the on-off of the PIGBT transistor Q7; the resistor R 12 and the resistor R 13 and the resistor R 14It forms the driving circuit of NIGBT tube Q8 together with high-voltage optocoupler OP4, and the Drive4 of the MCU drives and controls the on-off of NIGBT tube Q8; PIGBT tube Q5, NIGBT tube Q6, PIGBT tube Q7, and NIGBT tube Q8 form a high-voltage H-bridge inverter circuit to invert the high voltage HV+ of the boost circuit. The boost transformer T2 realizes further boosting and isolation of energy transfer, and inverts HV+ into alternating current with a higher voltage; due to the too high reverse voltage of the HV+ high-voltage H-bridge, the upper-arm power transistors cannot adopt the voltage pumping scheme of NMOS tubes Q1 and Q2 in the low-voltage inverter circuit. The upper-arm power transistors of the high-voltage inverter circuit of the present invention adopt P-type IGBTs, and use HV+ high voltage to drive PIGBT tubes Q5 and PIGBT tube Q7. The principle is as follows: when Drive1 is at a low level, the output end of the high-voltage optocoupler OP1 is cut off (i.e., the C pole and the E pole), and the emitter and gate voltages of PIGBT tube Q5 are zero, and the PIGBT tube is cut off; when Drive1 is at a high level, the output end of the high-voltage optocoupler OP1 is conducted, and resistors are connected in series between HV+ and HVGND. The emitter and gate voltages of PIGBT tube Q5 are the voltage on resistor R3. By selecting the resistance values of resistor R3 and resistor R5, the conduction of the high-voltage optocoupler OP1 and PIGBT tube Q5 is ensured; similarly, when Drive2 is at a high level, the high-voltage optocoupler OP2 is cut off, and resistor R6 and resistor R7 are connected in series between HV+ and HVGND. The gate and emitter voltages of NIGBT tube Q6 are the voltage on resistor R7. By selecting the resistance values of resistor R6 and resistor R7, the saturated conduction of NIGBT tube Q6 is ensured; when Drive2 is at a low level, the high-voltage optocoupler OP2 is saturated and conducted. Since resistor R7 is connected in parallel with the output end of the high-voltage optocoupler OP2, the voltage across resistor R7 is very small, and NIGBT tube Q6 is cut off; the working principles of PIGBT tube Q7 and NIGBT tube Q8 on the other arm are the same as those of PIGBT tube Q5 and NIGBT tube Q6.

[0022] The high-voltage shaping circuit includes resistor R 15 , capacitor C 12 and relay KA. One end of the resistor R 15 is connected to one pole of the output of the multi-way on-off inverter circuit. The other end of the resistor R 15 is connected to one pole piece of the pole piece group and one end of the capacitor C 12 . The other end of the capacitor C 12 is connected to the other pole piece of the pole piece group and the other pole of the output of the multi-way on-off inverter circuit; the relay KA is connected in parallel with the resistor R 15 . The control end of the relay KA is connected to the output end of the voltage stabilization control circuit; the resistor R 15 and the resistor R 15 form a first-order RC series circuit connected to both ends of the secondary side winding of the boost transformer T2. The relay KA is connected in parallel with the resistor R15 Both ends; capacitor C 12 Connect the two poles of the pole piece group at both ends, voltage v out Release electric energy to the human body lesion site, resistor R 15 With capacitor C 12 The circuit composed of shapes the PWM signal at both ends of the secondary side winding of the step-up transformer T2; when the relay KA is closed, v out Outputs a PWM square wave voltage; when the relay KA is open, v out Outputs a triangular wave or a sine wave, and regulates the output waveform and magnitude of v out

[0023] The voltage stabilization control circuit includes an MCU, a shunt resistor R sh , resistor R cf , resistor R1, resistor R2, capacitor C cf , capacitor C vf and a voltage stabilization module. The power supply terminal of the MCU is connected to the power supply voltage through the voltage stabilization module; the shunt resistor R sh is connected to the power supply voltage, one end of resistor R cf is connected to one end of the shunt resistor R sh , the other end of resistor R cf is connected to one end of capacitor C cf and the sampling terminal AD1 of the MCU. The other end of capacitor C cf is connected to the other end of the shunt resistor R sh ; one end of resistor R1 is connected to the power supply voltage, the other end of resistor R1 is connected to one end of resistor R2, one end of capacitor C vf and the sampling terminal AD2 of the MCU. The other end of resistor R2 is connected to the other end of capacitor C vf ; the signal output terminal of the MCU is connected to a low-voltage inverter circuit, a multi-way on-off inverter circuit and a high-voltage shaping circuit; resistor R sh converts the power supply output current i into a voltage signal. Resistor R cf and capacitor C cf form a first-order low-pass filter to filter the voltage of resistor R sh to obtain a voltage signal v1; resistor R1 and resistor R2 divide the power supply voltage to obtain a voltage signal v2. When dividing the voltage, in order to meet the requirements of AD sampling for voltage, capacitor C vf filters the interference of v2. The voltage stabilization module stabilizes the input power supply voltage V E to 3.3V to supply power to the MCU. The MCU controls the entire circuit, including the magnitude and electric energy control of the output voltage v out and the output voltage v out ​Waveform control; The MCU calculates the output electrical energy by sampling the power supply voltage and output current in real time, and adjusts the high-voltage HV+ of the boost circuit according to the relationship between the battery output electrical energy, the capacitor electrical energy, and the efficiency. Then, it regulates the duty cycles of the drive signals H1, H2, PWM1, and PWM2 of the NMOS transistors Q1, Q2, Q3, and Q4 in the low-voltage inverter circuit to stabilize HV+. Secondly, the MCU controls the waveforms of the drive signals Drive1 - Drive4 of the high-voltage inverter circuit and the drive signal CTL of the relay KA according to the waveform requirements of the output voltage v (for example, v is an AC symmetric triangular wave, a unipolar triangular wave, a sine wave, or a PWM square wave) to achieve the control of v. to obtain an approximation of the high voltage HV+ of the boost circuit, and then regulate the duty cycles of the drive signals H1, H2, PWM1, and PWM2 of the NMOS transistors Q1, Q2, Q3, and Q4 in the low-voltage inverter circuit to stabilize HV+. Secondly, according to the waveform requirements of the output voltage v out (for example, v out is an AC symmetric triangular wave, a unipolar triangular wave, a sine wave, or a PWM square wave), the MCU controls the waveforms of the drive signals Drive1 - Drive4 of the high-voltage inverter circuit and the drive signal CTL of the relay KA to achieve the control of v. out

[0024] As shown in the Figure 2 appendix, according to electrical engineering knowledge, when the time constant τ of the first-order RC circuit is less than the charging or discharging pulse time, the charging and discharging waveforms at both ends of its capacitor are approximately triangular waves. The smaller τ is, the more ideal the triangular wave is. Considering that the voltage peak value of the triangular wave needs to be relatively high, τ cannot be too small. Therefore, the triangular wave obtained in the present invention is an approximate triangular wave. Also, since the duty cycles of the drive waveforms of Drive1 - Drive4 are all 0.25, and the PWM waveforms of Drive1, Drive4 and Drive2, Drive3 are interleaved and complementary, so v out is a symmetric AC triangular wave.

[0025] As shown in the Figure 3 appendix, since the duty cycles of the drive waveforms of Drive1 - Drive4 are all 0.5, and the PWM waveforms of Drive1, Drive4 and Drive2, Drive3 are interleaved and complementary, all the charging charges during the conduction stage of Drive1 and Drive4 are released when Drive2 and Drive3 are conducting. If the capacitor C out has no charge when working, then the waveform of v 12 is a unipolar approximate triangular wave. out

[0026] As shown in the Figure 4 appendix, since the relay KA shorts the resistor R 15 , the output of v out is a square wave. At this time, the capacitor C 12 is used to eliminate the high-voltage spikes on the secondary output coil of the boost transformer T2 and stabilize v out .

[0027] As shown in the Figure 5 appendix, according to the SPWM modulation principle, the drive signals Drive1 - Drive4 are in accordance with theFigure 5 The PWM wave is output according to the shown principle. The voltage of the output coil on the secondary side of the boost transformer T2 passes through the resistor R 15 and the capacitor C 12 The voltage v obtained after filtering out is the sine wave; by adjusting the amplitude and frequency of the sine wave shown in the appendix Figure 5 the effective value and frequency of v out can be adjusted.

[0028] In summary, the power supply voltage of the present invention is converted into an AC voltage within a certain range through a low-voltage inverter circuit. After the AC voltage is boosted by a boost circuit, it is further inverted and waveform-controlled by a multi-way on-off inverter circuit. The waveform voltage of the multi-way on-off inverter circuit is finally output to the pole piece group after being shaped and waveform-switched by a high-voltage shaping circuit. The voltage of multiple waveforms is provided through the waveform control of the multi-way on-off inverter circuit and the waveform switching of the high-voltage shaping circuit.

Claims

1. A control circuit for a multi-mode electrotherapy instrument, comprising a power supply and an electrode plate group, characterized in that: The power supply is connected with a voltage stabilization control circuit and a low-voltage inverter circuit; an output side of the low-voltage inverter circuit is provided with a boost circuit, an output end of the boost circuit is connected with a multi-way on-off inverter circuit, and an output end of the multi-way on-off inverter circuit is connected with a high-voltage shaping circuit; the voltage stabilization control circuit is respectively connected with the power supply, the low-voltage inverter circuit, the multi-way on-off inverter circuit and the high-voltage shaping circuit; the voltage stabilization control circuit is used for obtaining the voltage and current of the power supply, and calculating control signals corresponding to the low-voltage inverter circuit, the multi-way on-off inverter circuit and the high-voltage shaping circuit according to the voltage and current of the power supply; after receiving the corresponding control signals, the low-voltage inverter circuit performs an inverter with a controllable output value on the voltage of the power supply and outputs an alternating voltage; the boost circuit boosts the alternating voltage of the low-voltage inverter circuit and outputs a boosted voltage; after receiving the corresponding control signals, the multi-way on-off inverter circuit performs an inverter and waveform control on the boosted voltage of the boost circuit through a combination of multi-circuit on-off and outputs a waveform voltage; after receiving the corresponding control signals, the high-voltage shaping circuit shapes the waveform voltage of the multi-way on-off inverter circuit and performs waveform switching through circuit on-off, and finally outputs to the electrode group; thus, through the waveform control of the multi-way on-off inverter circuit and the waveform switching of the high-voltage shaping circuit, the electrotherapy instrument generates physiotherapy voltages of multiple waveforms; the multi-way on-off inverter circuit includes resistor R3 - resistor R 14 , high-voltage optocouplers OP1 - OP4, PIGBT transistor Q5, NIGBT transistor Q6, PIGBT transistor Q7, NIGBT transistor Q8 and boost transformer T2; an emitter of the PIGBT transistor Q5 is connected with an output end of the boost circuit and one end of the resistor R3, a collector of the PIGBT transistor Q5 is connected with a collector of the NIGBT transistor Q6 and one pole of an input side of the boost transformer T2, a gate of the PIGBT transistor Q5 is connected with the other end of the resistor R3 and a C pole of the high-voltage optocoupler OP1, an E pole of the high-voltage optocoupler OP1 is connected with a weak-current circuit through the resistor R5, and a negative pole of the high-voltage optocoupler OP1 is grounded; an emitter of the NIGBT transistor Q6 is grounded, a gate of the NIGBT transistor Q6 is connected with one end of the resistor R6, one end of the resistor R7 and a C pole of the high-voltage optocoupler OP2, the other end of the resistor R6 is connected with the output end of the boost circuit, an E pole of the high-voltage optocoupler OP2 is connected with the other end of the resistor R7 and grounded, and a positive pole of the high-voltage optocoupler OP2 is connected with a power supply voltage; an emitter of the PIGBT transistor Q7 is connected with the output end of the boost circuit and one end of the resistor R9, a collector of the PIGBT transistor Q7 is connected with a collector of the NIGBT transistor Q8 and the other pole of the input side of the boost transformer T2, a gate of the PIGBT transistor Q7 is connected with the other end of the resistor R9 and a C pole of the high-voltage optocoupler OP3, an E pole of the high-voltage optocoupler OP3 is connected with the weak-current circuit through the resistor R 11 connected with the weak-current circuit, and a negative pole of the high-voltage optocoupler OP1 is grounded; an emitter of the NIGBT transistor Q8 is grounded, a gate of the NIGBT transistor Q8 is connected with one end of the resistor R 12 and one end of the resistor R 13 One end of and the C pole of the high-voltage optocoupler OP4, resistor R 12 The other end of is connected to the output end of the boost circuit, and the E pole of the high-voltage optocoupler OP4 is connected to resistor R 13 The other end of is grounded, and the positive pole of the high-voltage optocoupler OP4 is connected to the power supply voltage; the positive pole of the high-voltage optocoupler OP1 is connected to one end of resistor R4, the negative pole of the high-voltage optocoupler OP2 is connected to one end of resistor R8, and the positive pole of the high-voltage optocoupler OP3 is connected to resistor R 10 One end of, and the negative pole of the high-voltage optocoupler OP4 is connected to resistor R 14 One end of, resistor R4, resistor R8, resistor R 10 And resistor R 14 The other end of is connected to the output end of the voltage stabilization control circuit; the output side of the boost transformer T2 is connected to the high-voltage shaping circuit; the high-voltage shaping circuit includes resistor R 15 , capacitor C 12 And relay KA, the resistor R 15 One end of is connected to one pole of the output end of the multi-way on-off inverter circuit, and the resistor R 15 The other end of is connected to one pole piece of the pole piece group and one end of capacitor C 12 One end of capacitor C 12 The other end of is connected to the other pole piece of the pole piece group and the other pole of the output end of the multi-way on-off inverter circuit; the relay KA is connected in parallel with the resistor R 15 And the control end of the relay KA is connected to the output end of the voltage stabilization control circuit.

2. The control circuit of the multi-mode electrotherapy instrument according to claim 1, characterized in that: The low-voltage inverter circuit includes an NMOS transistor Q1, an NMOS transistor Q2, an NMOS transistor Q3, an NMOS transistor Q4, and a boost transformer T1; the drain of the NMOS transistor Q1 is connected to the positive power supply and the drain of the NMOS transistor Q2, the source of the NMOS transistor Q2 is connected to the drain of the NMOS transistor Q4, the source of the NMOS transistor Q1 is connected to the drain of the NMOS transistor Q3, and the source of the NMOS transistor Q3 is connected to the source of the NMOS transistor Q4 and the negative power supply; one end of the input side of the boost transformer T1 is connected to the source of the NMOS transistor Q1 and the drain of the NMOS transistor Q3, and the other end of the input side of the boost transformer T1 is connected to the source of the NMOS transistor Q2 and the drain of the NMOS transistor Q4; the gate and drain of the NMOS transistor Q1, the gate and drain of the NMOS transistor Q2, the gate of the NMOS transistor Q3, and the gate of the NMOS transistor Q4 are connected to the voltage stabilization control circuit; the output side of the boost transformer T1 is connected to the boost circuit.

3. The control circuit of the multi-mode electrotherapy instrument according to claim 1, wherein: The boost circuit includes capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, capacitor C9, capacitor C 10 , capacitor C 11 , diodes D1, D2, D3, D4, D5, D6, D7, D8, D9, diode D 10 and diode D 11 ; One end of the capacitor C1 is connected to one pole of the output end of the low-voltage inverter circuit, and the other end of the capacitor C1 is successively connected in series with capacitor C3, capacitor C5, capacitor C7, capacitor C9 and capacitor C 11 to form a first charging loop. One end of the capacitor C2 is connected to the other pole of the output end of the low-voltage inverter circuit, and the other end of the capacitor C2 is successively connected in series with capacitor C4, capacitor C6, capacitor C8 and capacitor C 10 to form a second charging loop; The end of the first charging loop is connected to the multi-way on-off inverter circuit; The diodes D1, D2, D3, D4, D5, D6, D7, D8, D9, diode D 10 and diode D 11 are connected between the first charging loop and the second charging loop in the form of a voltage multiplier circuit.

4. The control circuit of the multi-mode electrotherapy instrument according to claim 1, characterized in that: The voltage stabilization control circuit includes an MCU, a shunt resistor R sh , a resistor R cf , a resistor R1, a resistor R2, a capacitor C cf , a capacitor C vf and a voltage stabilization module. The power supply terminal of the MCU is connected to the power supply voltage through the voltage stabilization module; the shunt resistor R sh is connected to the power supply voltage. One end of the resistor R cf is connected to one end of the shunt resistor R sh . The other end of the resistor R cf is connected to one end of the capacitor C cf and the sampling terminal AD1 of the MCU. The other end of the capacitor C cf is connected to the other end of the shunt resistor R sh ; One end of the resistor R1 is connected to the power supply voltage. The other end of the resistor R1 is connected to one end of the resistor R2, one end of the capacitor C vf and the sampling terminal AD2 of the MCU. The other end of the resistor R2 is connected to the other end of the capacitor C vf ; The signal output terminal of the MCU is connected to a low-voltage inverter circuit, a multi-way on-off inverter circuit and a high-voltage shaping circuit.

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