Treatment equipment for radio frequency beauty instrument and radio frequency beauty instrument

Abstract

The invention relates to a treatment device and a radio frequency beauty instrument using the same, the treatment device comprises a detachable cold air tank, a control module, a touch screen, a radio frequency power amplification circuit, an automatic boost-buck power supply module, a power supply module and a switching interface, the control module is electrically connected with the touch screen and the automatic boost-buck power supply module; the input end of the radio frequency power amplification circuit is connected with the output end of the automatic buck-boost power supply module, the output end of the radio frequency power amplification circuit is connected with the adapter interface, and the radio frequency power amplification circuit is a symmetrical series-parallel resonance circuit and comprises a high-frequency isolation transformer, a third inductor, a capacitor and a parallel resonance circuit. The input end of the parallel resonance circuit is connected with the output end of the automatic buck-boost power supply module, the parallel resonance circuit is composed of a first circuit and a second circuit which are arranged in parallel, and each of the first circuit and the second circuit comprises a universal capacitor, a resonant capacitor, a switching tube and an inductor. The capacitor, the general capacitor, the resonant capacitor, the switching tube and the third inductor form a resonant cavity of the whole circuit topology.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a treatment device for a radio frequency beauty device and a radio frequency beauty device using the treatment device. Background Art

[0002] Radiofrequency beauty technology uses radiofrequency energy to act on the skin and fat tissue, causing the tissue to heat up and promote biological effects such as protein regeneration and fat dissolution. Currently, the more mature products in this field include Thermage, which uses capacitive coupling to apply radiofrequency energy to tissues, combined with cooling technology, to effectively reduce thermal damage while heating the target tissue.

[0003] However, during the interaction between radio frequency energy and tissue, there are usually the following problems: 1) Since the impedance between the probe and human skin is constantly changing, the device needs to be able to achieve high-frequency and high-power output in a wide range of impedance. 2) Due to the skin effect, there will be a certain difference in current density between the periphery of the probe electrode and the center of the electrode, which will cause certain thermal damage to the skin.

[0004] Chinese patent CN 118121830 A discloses a precise and fast tuning circuit for a radio frequency beauty instrument. It includes a DC power supply, a radio frequency power amplifier, a radio frequency current detection unit, a continuously adjustable inductance unit, a radio frequency load unit and a controller. The DC power supply is connected to the radio frequency power amplifier, and the radio frequency power amplifier, the radio frequency current detection unit, the continuously adjustable inductance unit and the radio frequency load unit are connected in sequence to form a radio frequency power output circuit. The radio frequency current detection unit is connected to the controller, and the detection result is sent to the controller. The controller controls the inductance value of the continuously adjustable inductance unit according to the detection result, so that the radio frequency power output circuit is in a series resonance state. The patent collects the real-time changes of the radio frequency current through the controller, and then controls the continuously adjustable inductance unit, changes its inductance value, and makes the loop current value change continuously until the maximum value of the loop current is found, so that the radio frequency power output circuit reaches a resonant state. However, this method has the following problems: 1) The circuit topology is only a simple series resonance, and a single resonant cavity is difficult to meet the filtering of high-frequency harmonics. Its output ripple is large, the output harmonic component is large, the effect is not single, the load network is poor, and the output effect is poor. 2) It is impossible to achieve soft switching, zero voltage turn-on or zero current turn-off, and the loss on the switch tube is unacceptable in high-power applications, and it cannot work in the high-power area for a long time. 3) The circuit structure is relatively complex. In order to achieve impedance matching, a variable inductor is added to the output side, which has poor control accuracy, low stability, and complex control. 4) In order to achieve high-power RF output, the inductor design is more difficult. Some inventions use hollow coils, but the electromagnetic radiation of hollow coils is large, which will affect other surrounding equipment when used.

[0005] Chinese patent CN 118178871 A discloses a radio frequency beauty instrument and a monopolar radio frequency electrode head. The monopolar radio frequency electrode head includes: a shell, an electrode member, and an insulating dielectric layer. Since the surface edge of the treatment part is arc-shaped, that is, an arc-shaped electrode member is used, compared with the traditional square electrode head, the circular or elliptical treatment part has no sharp angle, so the current concentration phenomenon at the edge can be reduced, thereby optimizing the current distribution, making the electric field distribution more uniform, and reducing the risk of burns during the use of the radio frequency beauty instrument. In addition, since a dielectric layer is provided on the surface of the treatment part facing the first opening, the metal surface of the treatment part does not directly contact the human body surface, but contacts the human body surface through the dielectric layer, and the radio frequency energy is coupled to the skin through the equivalent capacitance between the metal electrode and the human skin, thereby reducing the discomfort during use. This patent uses an arc-shaped electrode member to reduce the current concentration phenomenon at the edge, thereby optimizing the current distribution, making the electric field distribution more uniform, and reducing the risk of burns during the use of the radio frequency beauty instrument. However, this method has the following problems: 1) The arc electrode only solves the problem of the electrode not having a sharp angle, but cannot solve the problem of inconsistent current density at the electrode periphery and the electrode center caused by the skin effect. 2) Compared with the square electrode, the arc electrode has a smaller active area, so it may be necessary to increase the electrode size (and thus the handle size) or increase the action time to achieve the same effect. Summary of the invention

[0006] In view of the above analysis, the present invention aims to provide a therapeutic device for a radio frequency beauty instrument and a radio frequency beauty instrument using the therapeutic device, so as to solve the problem that the device can achieve high frequency, high power and high efficiency radio frequency output under a wide range of loads, and reduce thermal damage to skin tissue during the output process.

[0007] On the one hand, the present invention provides a therapeutic device for a radio frequency beauty instrument, the therapeutic device comprising a detachable cold air tank, a control module, a touch screen, a radio frequency power amplifier circuit, an automatic buck-boost power supply module, a power supply module and a transfer interface, the cold air tank is connected to the transfer interface through a pipeline, the control module is electrically connected to the touch screen and the automatic buck-boost power supply module, the input end of the radio frequency power amplifier circuit is connected to the output end of the automatic buck-boost power supply module, the output end of the radio frequency power amplifier circuit is connected to the transfer interface, the radio frequency power amplifier circuit is a symmetrical series-parallel resonant circuit, the symmetrical series-parallel resonant circuit comprises a high-frequency isolation transformer, a third inductor, a capacitor and a parallel resonant circuit, the input end of the parallel resonant circuit is connected to the output end of the automatic buck-boost power supply module, the parallel resonant circuit is composed of a first circuit and a second circuit arranged in parallel, the first circuit and the second circuit both comprise a universal capacitor, a resonant capacitor, a switch tube and an inductor, the capacitor, universal capacitor, resonant capacitor, switch tube and the third inductor constitute the resonant cavity of the entire circuit topology.

[0008] Based on the further improvement of the above scheme, the first circuit includes a first resonant capacitor, a first switch tube, a second inductor and a first general capacitor, the second circuit includes a second resonant capacitor, a second switch tube, a fourth inductor and a second general capacitor, the first switch tube and the second switch tube are alternately turned on, and in the process of the first switch tube and the second switch tube being alternately turned on, the composition of the resonant cavity is switched between the third inductor, the capacitor, the first resonant capacitor and the third inductor, the capacitor, and the second resonant capacitor.

[0009] Based on the further improvement of the above scheme, the high-frequency isolation transformer includes a magnetic core and a winding, and the magnetic core and the winding both use planar inductors, and the planar inductors are fixed by stacking multiple layers of different circuit boards with a fixed gap.

[0010] Based on the further improvement of the above solution, a DC blocking capacitor is provided in the high-frequency isolation transformer.

[0011] On the other hand, the present invention provides a radio frequency beauty instrument, comprising: a treatment device, a treatment handle, a back plate, a treatment probe and a switch, the treatment device comprising a detachable cold air tank, a control module, a touch screen, a radio frequency power amplifier circuit, an automatic step-up and step-down power supply module, a power supply module and an adapter, the treatment device is connected to the proximal end of the treatment handle through the adapter, the switch is electrically connected to the control module in the treatment device, the treatment probe is installed at the distal end of the treatment handle, the treatment handle comprises a handle housing and a handle cable, the handle cable consists of a circuit harness and a cold air pipeline, one end of the cold air pipeline is connected to the cold air tank in the treatment device through the adapter, and the other end of the cold air pipeline is connected to the cold air port set in the treatment probe. The circuit harness is electrically connected to the control module and the output end of the radio frequency power amplifier circuit through the adapter, and the other end of the circuit harness is connected to the treatment electrode arranged on the treatment probe. The radio frequency power amplifier circuit is a symmetrical series-parallel resonant circuit, which includes a high-frequency isolation transformer, a third inductor and a capacitor and a parallel resonant circuit. The input end of the parallel resonant circuit is connected to the output end of the automatic step-up and step-down power supply module. The parallel resonant circuit is composed of a first circuit and a second circuit arranged in parallel. The first circuit and the second circuit both include a universal capacitor, a resonant capacitor, a switch tube and an inductor. The capacitor, the universal capacitor, the resonant capacitor, the switch tube and the third inductor constitute a resonant cavity of the entire circuit topology.

[0012] Based on the further improvement of the above scheme, the cold air tank is connected to the adapter through a pipeline, the control module is electrically connected to the touch screen and the automatic step-up and step-down power supply module, the power supply module is connected to the power supply interface, and is used to power the touch screen, the control module and the automatic step-up and step-down power supply module, the input end of the RF power amplifier circuit is connected to the output end of the automatic step-up and step-down power supply module, and the output end of the RF power amplifier circuit is connected to the adapter, the first circuit includes a first resonant capacitor, a first switch tube, a second inductor and a first general capacitor, the second circuit includes a second resonant capacitor, a second switch tube, a fourth inductor and a second general capacitor, the first switch tube and the second switch tube are alternately turned on, and in the process of alternating conduction of the first switch tube and the second switch tube, the composition of the resonant cavity is switched between the third inductor, the capacitor, the first resonant capacitor and the third inductor, the capacitor, and the second resonant capacitor.

[0013] Based on the further improvement of the above solution, a DC blocking capacitor is provided in the high-frequency isolation transformer.

[0014] As a further improvement of the above solution, the switch is a foot switch directly connected to a control module of the therapeutic device.

[0015] Based on the further improvement of the above scheme, the switch is an excitation button arranged on the handle housing, and the treatment handle also includes a parameter setting component arranged on the handle housing and a control circuit board arranged in the handle housing, the excitation button and the parameter setting component are electrically connected to the control circuit board, and the control circuit board is electrically connected to the control module through the circuit harness.

[0016] Based on the further improvement of the above solution, the parameter setting component includes a radio frequency energy increase button, a radio frequency energy decrease button, a vibration adjustment button and a parameter confirmation button.

[0017] Based on the further improvement of the above solution, a temperature sensor and a pressure sensor are arranged in the treatment probe, and the temperature sensor and the pressure sensor are connected to the control circuit board. Preferably, the temperature sensor and the cold air outlet are distributed in a high-density array.

[0018] Based on a further improvement of the above solution, the treatment probe is elastically connected to the handle shell.

[0019] Based on a further improvement of the above solution, an insulating material is provided on the treatment probe.

[0020] As a further improvement of the above solution, a metal ring is arranged around the treatment electrode. Preferably, the metal ring is located inside the treatment probe.

[0021] In another aspect, the present invention provides a method for controlling a radio frequency beauty instrument, comprising the following steps:

[0022] Step 1: Turn on the radio frequency beauty instrument through the foot switch or the excitation button;

[0023] Step 2: Set the output parameters through the touch screen or parameter setting components;

[0024] Step 3: Measure the detection pressure and detection temperature through the pressure sensor and the temperature sensor, and compare them with the threshold pressure and threshold temperature respectively through the control circuit board. When the detection pressure is less than the threshold pressure and / or the detection temperature is greater than the threshold temperature, no RF output is performed; when the detection pressure is greater than the threshold pressure and the detection temperature is less than the threshold temperature, energy output is performed with the initially set parameters;

[0025] Step 4: During the energy output process, the load impedance, pressure, and temperature data are detected in real time, and it is determined whether the data are within the normal range. Once abnormal, the energy output is stopped;

[0026] Step 5: During the energy output process, the RF output power and cold air flow are adjusted according to the changes in the load impedance, pressure, and temperature data detected in the fourth step, and the output of the RF beauty instrument is adjusted in a negative feedback manner until the operation is completed.

[0027] The beneficial effects of the above technical solution are as follows:

[0028] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0029] 1. The present invention proposes a novel radio frequency power amplifier circuit, which is based on a symmetrical series-parallel resonant circuit to realize multiple resonant cavities. Through the series-parallel combination of inductors and capacitors, the load resistance can be converted into a smaller characteristic impedance, so that the radio frequency energy can be output at a high frequency and high power within a larger load impedance range.

[0030] 2. The RF power amplifier circuit of the present invention connects an inductor in series with the output load. Since there is parasitic capacitance on the load, connecting an inductor in series with the load can form a resonant cavity, which can offset the capacitance on the load, thereby increasing the resistive energy on the load and improving the output efficiency of RF energy.

[0031] 3. The RF power amplifier circuit of the present invention adds a high-frequency isolation transformer between the RF output and the load. The magnetic core of the high-frequency isolation transformer uses a planar inductor. Different circuit boards are stacked on the planar inductor and a multi-layer stacking design is performed with an air gap of a specific thickness. The expected high-frequency isolation can be obtained through this gap, and the multi-layer stacking achieved by the circuit board also has a higher turns ratio accuracy, which can not only ensure that the withstand voltage of the high-frequency isolation transformer meets the requirements, but also ensure that the leakage inductance value is within a suitable range. This design can electrically isolate high-frequency and high-power RF energy above 5M, thereby improving the safety of the application end.

[0032] 4. The present invention provides an insulator on the treatment probe and adds a metal ring around the treatment electrode. Due to the presence of the insulator, the RF source will not generate actual RF current flow between the treatment electrode and the back plate, but the generated RF electric field will cause the ions in the tissue to move at high speed and heat up through friction. The role of the metal ring is to form an equipotential area around the contact part between the treatment electrode and the insulator and the tissue. The existence of this area can offset the skin effect, making the electrode current density evenly distributed, thereby reducing the probability of local thermal damage.

[0033] 5. The temperature sensors and cold air vents of the present invention are distributed in a high-density array, so that the radio frequency beauty instrument can detect the temperature of each area of ​​the treatment electrode in real time during operation, and adjust the airflow size of each cold air vent in real time accordingly to ensure that the temperature of the skin action site is consistent, thereby further reducing the chance of thermal damage.

[0034] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be achieved and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0036] Figure 1A This is a schematic diagram of the structure of a radio frequency beauty instrument treatment device.

[0037] Figure 1B This is a schematic diagram of the structural connection of the treatment equipment of the radio frequency beauty instrument.

[0038] Figure 1C This is a schematic diagram of the overall structure of the radio frequency beauty instrument.

[0039] Figure 2A This is a schematic diagram of the front structure of the treatment handle.

[0040] Figure 2B This is a schematic diagram of the back structure of the treatment handle.

[0041] Figure 3 Schematic diagram of the internal structure of the treatment handle.

[0042] Figure 4 A schematic diagram of an implementation of a symmetrical radio frequency power amplifier circuit.

[0043] Figure 5 It is a structural schematic diagram of a high-frequency isolation transformer.

[0044] Figure 6 Schematic diagram of electric field distribution when radio frequency energy acts on tissue.

[0045] Fig. 7A Schematic diagram of the electric field distribution on the surface of a common electrode.

[0046] Figure 7B Schematic diagram of the electric field distribution when a metal ring is added to the electrode surface.

[0047] Figure 8 Schematic diagram of the internal structure of the treatment electrode.

[0048] Fig. 9 This is the system control flow chart of the radio frequency beauty instrument.

[0049] Fig.10 This is a schematic diagram of the negative feedback control principle of the radio frequency beauty instrument output. DETAILED DESCRIPTION

[0050] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and examples.

[0051] The “proximal end” mentioned in the present invention refers to the end close to the surgical operator, and the “distal end” mentioned in the present invention refers to the end far away from the surgical operator.

[0052] like Figure 1A and Figure 1B As shown, a treatment device 1 for a radio frequency beauty instrument, the treatment device 1 includes a detachable cold air tank 13, a control module 14, a touch screen 12, a radio frequency power amplifier circuit 15, an automatic step-up and step-down power supply module 16, a power supply module 17 and an adapter 11, the cold air tank 13 is connected to the adapter 11 through a pipeline, the control module 14 is electrically connected to the touch screen 12, the cold air tank 13 and the automatic step-up and step-down power supply module 16, the input end of the radio frequency power amplifier circuit 15 is connected to the output end of the automatic step-up and step-down power supply module 16, the output end of the radio frequency power amplifier circuit 15 is connected to the adapter 11, and the power supply module 17 is connected to the power supply interface 18 for supplying power to the touch screen 12, the control module 14 and the automatic step-up and step-down power supply module 16. The control module 14 controls the amount of cold air delivered by the cold air tank 13 to the adapter 11. Figure 4 As shown, the RF power amplifier circuit 15 is a symmetrical series-parallel resonant circuit, which includes a high-frequency isolation transformer 151, a third inductor L3, a capacitor C4 and a parallel resonant circuit 152. The input end of the parallel resonant circuit 152 is connected to the output end of the automatic step-up and step-down power supply module 16. The parallel resonant circuit 152 is composed of a first circuit 1521 and a second circuit 1522 arranged in parallel. The first circuit 1521 and the second circuit 1522 both include a general capacitor, a resonant capacitor, a switch tube and an inductor. The capacitor, the general capacitor, the resonant capacitor, the switch tube and the third inductor constitute the resonant cavity of the entire circuit topology. Figure 4 As shown, the first circuit 1521 includes a first resonant capacitor C5, a first switch tube Q1, a second inductor L2 and a first general capacitor C7, and the second circuit 1522 includes a second resonant capacitor C6, a second switch tube Q3, a fourth inductor L4 and a second general capacitor C9.

[0053] The network power supply (220V AC mains) is converted into a DC power supply through a medical switching power supply, and the DC power supply is converted into an adjustable power supply HV through an automatic step-up and step-down power supply module 16. Since the operating frequency of the radio frequency beauty instrument is relatively high (usually higher than 5MHz), there are certain requirements for the transient output current capability of the adjustable power supply HV, so the first general capacitor C7 and the second general capacitor C9 are required to supply transient current, and the first inductor L2 and the second inductor L4 are chokes to reduce current ripple. Therefore, the first general capacitor C7 and the second inductor L2, the second general capacitor C9 and the fourth inductor L4 ensure that HVDC can provide a stable current to the radio frequency power amplifier circuit 15 to form an input current source. The first switch tube Q1, the second switch tube Q3, the third inductor L3, and the capacitor C4, the first resonant capacitor C5, and the second resonant capacitor C6 constitute the main resonant cavity of the entire circuit topology, and the first resonant capacitor C5 and the second resonant capacitor C6 remain symmetrical. A DC blocking capacitor C3 is provided in the high-frequency isolation transformer 151 to filter out the smaller DC component on the output side in practical applications. The high-frequency isolation transformer 151 is used to isolate the RF output from the application part. The first switch tube Q1 and the second switch tube Q3 are alternately turned on, that is, the drive signals G_N and G_P are square waves with a phase difference of 180°, and the square wave frequency determines the frequency of the RF output signal. In the process of the first switch tube Q1 and the second switch tube Q3 being alternately turned on, the composition of the resonant cavity is switched between the third inductor L3, the capacitor C4, the first resonant capacitor C5 and the third inductor L3, the capacitor C4, the second resonant capacitor C6. The capacitors, general capacitors, resonant capacitors, inductors, switch tubes and other components described in this application all use common components of the RF power amplifier circuit in the prior art, and there are no special requirements for their parameters.

[0054] The RF power amplifier circuit of the prior art generally adopts a series resonance mode, such as the circuit disclosed in Figure 2 of Chinese Patent CN 118121830A. The sum of the reactances of L and C in the series resonance circuit is zero, which is short-circuited, and forms a constant voltage source with an ideal frequency with the power supply, and its output end obtains an oscillating voltage with a constant output peak value. The performance characteristics of series resonance are better when the load is small, but the larger the load impedance, the smaller the circuit quality factor, resulting in a larger overall circuit loss, thereby reducing the efficiency of the circuit. The human body impedance range is large, so the output effect of the series resonance circuit in a large impedance range is not ideal.

[0055] The radio frequency power amplifier circuit 15 described in the present invention is a series-parallel resonant circuit. The input current source charges the first resonant capacitor C5 to form a voltage source; this voltage source and the third inductor L3 can be transformed into an equivalent current source and an equivalent inductor, and the equivalent inductor and the capacitor C4 form a parallel resonance. The equivalent current source provides a load (for example, a treatment end connected to the transfer interface 11) with a constant peak oscillating current through this parallel resonance. Since the first resonant capacitor C5 and the third inductor L3 in the circuit are connected in series, a series-parallel resonant circuit is essentially formed. The new symmetrical radio frequency power amplifier circuit 15 described in the present invention, based on the series-parallel resonant circuit, can convert the load resistance into a smaller characteristic impedance through the series-parallel combination of inductors and capacitors, thereby achieving high-efficiency output under a larger load range. The above content is an explanation when the first switch tube Q1 is turned off and the second switch tube Q3 is turned on; when the second switch tube Q3 is turned off and the first switch tube Q1 is turned on, the above description is also applicable to the resonant circuit formed by the second resonant capacitor C6, the third inductor L3 and the capacitor C4.

[0056] If the treatment end (e.g., treatment probe) is not in direct contact with the skin tissue, the RF energy acts on the skin through capacitive coupling. Therefore, there is a parasitic capacitor in the load caused by the insulating medium on the surface of the treatment probe contacting the skin. The parasitic capacitor has a large capacitive reactance and is in series with the load, so it will take away most of the output energy. The present invention compensates for the parasitic capacitor generated at the output end by adding an inductor L1, thereby increasing the actual power obtained on the load. Specifically, as Figure 4 As shown, the present invention adds a first inductor L1 to the high-frequency isolation transformer 151. The parasitic capacitance is compensated by the additional first inductor L1, that is, the capacitive reactance of the parasitic capacitance is offset by the inductive reactance of the first inductor L1. After compensation, only a small inductive reactance and load are left at the output end of the high-frequency isolation transformer 151, and most of the output energy can act on the load (i.e., the treatment end), thereby increasing the actual power obtained on the load.

[0057] In addition, the novel symmetrical RF power amplifier circuit 15 described in the present invention is a push-pull output, and the left and right circuits only work for half of the time in a switching cycle. The energy output by the RF power amplifier is simultaneously supplied by two constant current sources formed by HV, the first general capacitor C7, the second inductor L2 and HV, the second general capacitor C9, and the fourth inductor L4. Therefore, the current stress on the switch tube is reduced to half of the original. And its output is only half a cycle, and the output range of the original peak-to-peak value is reduced to the peak output, and the voltage is reduced to half of the original. Under the original condition of the same voltage stress, its unilateral output amplitude can be higher, and the power is a quadratic function of the voltage, so the output power can be increased to 4 times the original, thereby achieving a higher output power.

[0058] In high-frequency circuits, the voltage and current overlap during the on and off process of the switch tube, resulting in turn-on loss and turn-off loss during the on and off process of the switch tube. As the switching frequency increases, the proportion of switching loss generated during the switching process gradually increases, which will greatly reduce the working efficiency of the circuit. Figure 4 As shown, the new symmetrical RF power amplifier circuit of the present invention has a current i flowing through the parallel capacitors, the first resonant capacitor C5 and the second resonant capacitor C6. C (t) is:

[0059]

[0060] Where i1 is the current provided by the input current source, i L (t) is the current flowing through the resonant inductor L3. The voltage across the parallel capacitors C5 and C6 is v c (t) is the integral of the current flowing to it, that is:

[0061]

[0062] The novel symmetrical RF power amplifier circuit has zero voltage start and zero current shutdown, and the following boundary conditions are obtained:

[0063]

[0064] Substituting equation (1.3) into equation (1.1) and equation (1.2), we get the following formula:

[0065]

[0066] Based on the above analysis, the resonant inductor current i can be obtained. L The amplitude-frequency and phase-frequency relationship between (t) and the equivalent current source i1 is as follows:

[0067]

[0068] Among them, characteristic impedance Z0, quality factor Q L , the first resonant angular frequency ω0, and the second resonant angular frequency ω1 are as follows:

[0069]

[0070] final, Figure 4 The resonant circuit parameters shown are as follows:

[0071]

[0072] Based on the analysis of equations (1.1) to (1.8), the novel symmetrical RF power amplifier circuit of the present invention can realize high-frequency soft opening of the switch tube. Specifically, based on Figure 4 The symmetrical series-parallel resonant circuit shown, by introducing the second inductor L2 and the fourth inductor L4 and the first resonant capacitor C5 and the second resonant capacitor C6, can make the voltage across the switch tube zero when it is turned on, and the current flowing through it is zero when it is turned off (i.e., zero voltage turn-on, zero current turn-off), thereby greatly reducing the switching loss and improving the working efficiency of the circuit.

[0073] The general RF power amplifier circuit is a single-ended circuit topology, and the output contains not only odd harmonics but also even harmonics. The novel symmetrical RF power amplifier circuit described in the present invention is a push-pull output, and the even harmonic components output under push-pull drive can be ignored. Its output waveform satisfies the odd harmonic function, and the corresponding Fourier series expansion is as follows:

[0074]

[0075] Calculate a n We can get:

[0076]

[0077] For formula (1.10), when n is an even number, a n is equal to 0; when n is an odd number, a n is not equal to 0, b in formula (1.9) n with a n Similarly. Therefore, in the half-wave symmetrical function, its Fourier expansion contains only fundamental wave components and odd harmonic components, but no even harmonic components. Based on the push-pull output mode, the higher harmonic components of the odd harmonic components in the output are reduced, and the even harmonic components can also be ignored, so the quality of the output waveform is improved, thereby improving the working efficiency of the circuit.

[0078] For high-frequency (usually above 5MHz) applications, it is difficult to isolate high-frequency energy on the output side. Traditional high-frequency isolation is mainly achieved through air gaps. Due to improper selection of transformer cores and improper structural design, the transformer leakage inductance is large, affecting the resonant circuit, causing a sharp increase in switch tube losses, or large parasitic parameters, causing waveform distortion, etc. Figure 5As shown, the high-frequency isolation transformer of the present invention includes a magnetic core 143 and a winding 144, and the magnetic core 143 and the winding 144 are both planar inductors, and the planar inductors are fixed by stacking multiple layers with fixed gaps using different circuit boards. The different circuit boards are a primary circuit board 141 and a secondary circuit board 142, and the primary circuit board 141 and the secondary circuit board 142 are designed to be stacked in multiple layers with an air gap of a specific thickness. The expected high-frequency isolation can be obtained through this gap, and the primary and secondary multi-layer stacking achieved by the circuit board also has a higher turns ratio accuracy. This design can ensure that the withstand voltage between the primary and secondary of the high-frequency isolation transformer meets the requirements, and can also ensure that the leakage inductance value is within a suitable range, thereby achieving isolation of high-frequency energy. This design can electrically isolate high-frequency and high-power radio frequency energy above 5M, thereby improving the safety of the application end.

[0079] like Figure 1C As shown, a radio frequency beauty instrument includes the treatment device 1 described above, a treatment handle 2, a back plate 3, a switch and a treatment probe 5. Figure 1A As shown, the therapeutic device 1 includes a detachable cold air tank 11, a control module 14, a touch screen 12, a radio frequency power amplifier circuit 15, an automatic step-up and step-down power supply module 16, a power supply module 17 and a transfer interface 11. The specific structure of the therapeutic device 1 is as described above. The therapeutic device 1 is connected to the proximal end of the therapeutic handle 2 through the transfer interface 11, the switch is electrically connected to the control module 14 in the therapeutic device 1, and the therapeutic probe 5 is installed at the distal end of the therapeutic handle 2. Figure 2A As shown, the treatment handle 2 includes a handle housing 22 and a handle cable 23. Figure 3As shown, the handle cable 23 is composed of a circuit harness 231 and a cold air pipeline 232. One end of the cold air pipeline 232 is connected to the cold air tank 13 in the treatment device 1 through the adapter 11, and the other end of the cold air pipeline 232 is connected to the cold air port 53 set in the treatment probe 5. One end of the circuit harness 231 is electrically connected to the output end of the control module 14 and the radio frequency power amplifier circuit 15 through the adapter 11, and the other end of the circuit harness 231 is connected to the treatment electrode 51 set on the treatment probe 3. The treatment probe 5 acts on the surface of the human skin, and the back plate 3 is in good contact with the back of the human body through the conductive paste. One end of the radio frequency energy generated by the treatment device 1 acts on the treatment probe 5 at the head end of the treatment handle 2, and the other end acts on the back plate 3, thereby forming a radio frequency current loop. Usually, the back plate 3 is close to the back of the human body, and there is a large contact area between the back plate 3 and the back of the human body. In addition, a layer of conductive gel is usually applied between the back plate 3 and the back of the human body. The above method makes the back plate 3 and the back of the human body have a lower contact impedance and a lower current density. Therefore, most of the radio frequency energy is concentrated at the head end of the treatment electrode 5. The radio frequency energy interacts with the skin tissue, warms the tissue and promotes protein regeneration and fat dissolution, thereby achieving the effect of radio frequency beauty. The cold air in the cold air tank 13 and the radio frequency energy generated by the treatment device 1 act together on the head end of the treatment probe 5 through the adapter 11. The cold air includes but is not limited to CO2, N20, Freon, liquid nitrogen or argon. During the treatment process, if the treatment device 1 detects that the temperature at the skin tissue is too high, it can increase the cold air flow to neutralize the additional heat generated by the head end of the treatment probe 5 that is not used for treatment, thereby reducing thermal damage to the skin. In one embodiment, the switch is a foot switch 4 directly connected to the control module of the treatment device 1. When the foot switch 4 is pressed, the radio frequency energy of the treatment device 1 and the cold air in the cold air tank 13 can act on the head end of the treatment probe 5. The touch screen 12 in the treatment device 1 is used to set parameters before treatment, such as the selection of treatment gear and vibration gear, etc., and to display parameter information during treatment in real time, such as output energy and number of treatments, etc. In addition, the touch screen 12 can also prompt the user to perform corresponding operations at different treatment stages and display abnormal status of the current device, etc.

[0080] In one embodiment, the switch is an activation button 24 disposed on the handle housing 22. Figure 2A and Figure 3As shown, the treatment handle 2 includes a handle housing 22, a handle cable 23, an excitation button 24, a parameter setting component 25 arranged on the handle housing, and a control circuit board 223 arranged in the handle housing 22, the excitation button 24 and the parameter setting component 25 are electrically connected to the control circuit board 223, and the control circuit board 223 is electrically connected to the control module 14 in the treatment device 1 through the circuit harness 231. The treatment probe 5 can be inserted into the distal end of the treatment handle 2 and fixed thereto. The excitation button 24 is arranged on the front of the treatment handle 2. The function of the excitation button 24 is similar to that of the foot switch 4. When the excitation button 24 is pressed, the radio frequency energy of the treatment device 1 and the cold air in the cold air tank 13 can act on the head end of the treatment probe 5. As shown Figure 2B As shown, the parameter setting component 25 is arranged on the back of the treatment handle 2, and the parameter setting component 25 includes a radio frequency energy increase button 251, a radio frequency energy decrease button 252, a vibration adjustment button 253, and a parameter confirmation button 254. When setting parameters, it is necessary to first press the corresponding button on the parameter setting component 25, and finally press the parameter confirmation button 254, so that the parameter setting can take effect; if the parameter confirmation button 254 is not pressed, the system retains the previous parameters.

[0081] Figure 3The handle cable 23 includes a circuit harness 231 and a cold air pipeline 232. The radio frequency energy generated by the treatment device 1 is transmitted to the treatment electrode 51 through the circuit harness 231, thereby performing radio frequency heating on the skin tissue. The cold air in the cold air tank 13 is connected to the solenoid valve 221 through the cold air pipeline 232. During the treatment process, the solenoid valve 221 is in a normally open state. If the treatment device 1 detects that the temperature at the skin tissue is too high, it can increase the cold air flow rate and act on the treatment electrode 51 through the cold air port 53 to neutralize the additional heat generated by the head end of the treatment probe 5 that is not used for treatment, and cool the skin tissue, thereby controlling thermal damage. A control circuit board 223 is integrated inside the treatment handle 2 and fixed to the handle housing 22 through a circuit board fixing member 224. A temperature sensor 52 is installed inside the treatment probe 5, which can monitor the temperature change of the treatment electrode 51 in real time during the treatment process. The control circuit board 223 processes the temperature information and transmits it to the control circuit 14 inside the treatment device 1 through the circuit harness 231 to adjust the radio frequency energy and cold air. Specifically, the parameter setting component 25 and the touch screen 12 on the treatment handle 2 are used to perform initial parameter settings before treatment. During the treatment process, the treatment device 1 will adjust the current radio frequency energy and the flow of cold air in real time according to the temperature change of the treatment electrode 51, so as to reduce the additional heat generated by the head end of the treatment probe 5 that is not used for treatment as much as possible, thereby controlling thermal damage. A pressure sensor 222 is also installed inside the treatment probe 5. The treatment probe 5 is elastically connected to the handle shell 22, and a motor 55 is provided inside the treatment probe 5. The motor 55 is fixedly connected to the shell of the treatment probe 5, and the power supply line and control signal line of the motor 55 are connected to the control circuit board 223. During the treatment process, the control circuit board 223 will continuously control the vibration of the motor 55, thereby driving the treatment probe 5 to continuously vibrate to reduce the neuromuscular stimulation that may exist during the treatment process. The force of the treatment probe 5 can be detected in real time by the pressure sensor 222, and fed back to the control circuit board 223, and transmitted to the control circuit inside the treatment device 1 through the circuit harness 231. The temperature sensors 52 of the present invention are distributed in a high-density array, and the cold air outlets 53 are also distributed in a high-density array. The radio frequency beauty instrument can detect the temperature of the treatment electrode 51 action area in real time during operation, and adjust the airflow size of each cold air outlet 53 in real time accordingly to ensure that the temperature of the skin action area is consistent, thereby further reducing the probability of thermal damage.

[0082] Figure 8 The internal structure of the treatment electrode 51. The treatment electrode 51 is located on the surface of the flexible circuit board 56, and the flexible circuit board 56 can be well connected to the skin tissue through the insulator 261. In one embodiment, an insulator is provided on the treatment probe 5. Figure 6As shown, due to the presence of the insulator 261, the RF source 111 output by the treatment device 1 does not generate actual RF current flow between the treatment electrode 51 and the back plate 3, but the generated RF electric field causes the ions in the tissue to move at high speed and heat up through friction. The flexible circuit board can fit the skin tissue better during treatment to achieve a more complete treatment effect. The treatment probe 5 of the present invention is capacitively coupled with the skin tissue 61, and the RF energy does not directly contact the human skin. There is a layer of insulator 261 (including but not limited to polyimide) between the treatment probe 5 and the skin tissue 61 of the human body. The energy is transmitted in the form of a field, and the RF penetrates through the skin to the subcutaneous tissue. The high-frequency vibration and resistive heat cause the subcutaneous tissue to heat up, thereby promoting collagen regeneration.

[0083] When ordinary electrodes are used, the electric field distribution on the surface of the ordinary electrodes is as follows: Fig. 7A As shown. When ions in tissue move at high speed under the action of the radio frequency electric field, the movement and heating effects under different electric field strengths are different. Usually at the edge 511, especially at a position with a sharp angle, the electric field is stronger, the ion movement speed is faster, the heating effect is more obvious, and it is also easy to cause unexpected thermal damage. The present invention is provided with a metal ring 54 around the treatment electrode 51. The electric field distribution of the treatment electrode 51 is as shown in FIG. Figure 7B As shown. The metal ring 54 and the treatment electrode 51 are connected by a fixed structure. The metal ring 54 is in direct contact with the tissue, but there is no electrical connection between the metal ring 54 and the treatment electrode 51. Its function is to form an equipotential area around the contact part of the treatment electrode 51 and the insulator 261 with the tissue. The existence of this area makes the ions in the material near it in a uniform radio frequency electric field, thus forming a uniform high-speed motion and generating a uniform thermal effect, which can avoid local overheating, and the uniform thermal effect is more controllable.

[0084] The head end of the treatment probe 5 of the present invention can be selected to be square, and a metal ring 54 is added around the action area of ​​the treatment electrode 51. The metal ring 54 has no electrical properties, and the distance between the metal ring 54 and the action area is preferably 1 mm. The metal ring 54 is located on the inner side of the treatment probe 5. The metal ring 54 can be realized by opening a window of the copper foil on the flexible circuit board 56, or by welding an additional layer of metal ring on the flexible circuit board, and no treatment is done on the back of the flexible circuit board. The metal ring 54 affects the action area through induced electricity, making the action area equipotential. The formation of equipotential makes the current more uniform when the radio frequency acts, reduces the thermal damage at the edge, and maintains the efficient probe action area.

[0085] Fig. 9 The control method of the radio frequency beauty instrument of the present invention comprises the following steps:

[0086] Step 1: Turn on the radio frequency beauty instrument through the foot switch or the excitation button;

[0087] Step 2: Set the output parameters through the touch screen or parameter setting components;

[0088] Step 3: Measure the detection pressure and detection temperature through the pressure sensor and the temperature sensor, and compare them with the threshold pressure and threshold temperature respectively through the control circuit board. When the detection pressure is less than the threshold pressure and / or the detection temperature is greater than the threshold temperature, no RF output is performed; when the detection pressure is greater than the threshold pressure and the detection temperature is less than the threshold temperature, energy output is performed with the initially set parameters;

[0089] Step 4: During the energy output process, the load impedance, pressure, and temperature data are detected in real time, and it is determined whether the data are within the normal range. Once abnormal, the energy output is stopped;

[0090] Step 5: During the energy output process, the RF output power and cold air flow are adjusted according to the changes in the load impedance, pressure, and temperature data detected in the fourth step, and the output of the RF beauty instrument is adjusted in a negative feedback manner until the operation is completed.

[0091] That is to say, after the radio frequency beauty instrument is turned on, the user can set the output parameters through the touch screen 12 or the parameter setting component 25 on the back of the treatment handle 2, and then the system will detect whether the pressure and temperature at the treatment electrode 51 are normal. Specifically, if the detection pressure is less than the threshold pressure F0, it is considered that the treatment electrode 51 is not well attached to the skin tissue, and the radio frequency output cannot be performed at this time until the detection pressure is greater than F0. If the detection temperature is greater than the threshold temperature T0, it is considered that the thermal damage during the treatment process is too large, and the radio frequency output cannot be performed at this time until the detection temperature is less than T0. When the detection pressure is greater than F0 and the detection temperature is less than T0, energy output begins with the initially set parameters. During the output process, the system will detect the load impedance, pressure, and temperature data in real time, and determine whether the pressure and temperature are within the normal range. Once abnormal, the energy output will be stopped. In addition, the system will also adjust the radio frequency power output and the cold air flow rate in real time according to the changes in the load impedance, pressure, and temperature data, so as to achieve the purpose of treatment while reducing the contact temperature between the skin tissue and the treatment electrode 51 to reduce tissue thermal damage.

[0092] Fig.10 This is the schematic diagram of the negative feedback control output of the radio frequency beauty instrument. Fig. 9In the stage of setting output parameters, the operator can set the initial RF output power and cold air flow. During the RF output process, the system will detect the impedance, pressure and temperature parameters at the treatment electrode 51 in real time, and determine the increment of the current RF output power and cold air flow according to the changes in these parameters, so as to adjust the output of the RF beauty instrument in a negative feedback manner. Specifically, if the impedance detection value increases, the RF output power is increased, otherwise, the RF output power is reduced; if the pressure detection value increases, the RF output power is reduced, otherwise, the RF output power is increased; if the temperature detection value increases, the RF output power is reduced and the cold air flow is increased, otherwise, the RF output power is increased and the cold air flow is reduced. Based on the negative feedback adjustment method of the output of the RF beauty instrument, it is possible to reduce thermal damage to skin tissue while ensuring effective treatment effects.

[0093] The above description of the present application is intended to enable persons familiar with the technology in this field to understand the content of the present invention and implement it, and it is not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A treatment device for a radio frequency beauty instrument, characterized in that: The therapeutic device includes a detachable cold air tank, a control module, a touch screen, a radio frequency power amplifier circuit, an automatic buck-boost power supply module, a power supply module and an adapter. The cold air tank is connected to the adapter through a pipeline, the control module is electrically connected to the touch screen and the automatic buck-boost power supply module, the input end of the radio frequency power amplifier circuit is connected to the output end of the automatic buck-boost power supply module, the output end of the radio frequency power amplifier circuit is connected to the adapter, the radio frequency power amplifier circuit is a symmetrical series-parallel resonant circuit, the symmetrical series-parallel resonant circuit includes a high-frequency isolation transformer, a third inductor, a capacitor and a parallel resonant circuit, the input end of the parallel resonant circuit is connected to the output end of the automatic buck-boost power supply module, the parallel resonant circuit is composed of a first circuit and a second circuit arranged in parallel, the first circuit and the second circuit both include a general capacitor, a resonant capacitor, a switch tube and an inductor, the capacitor, the general capacitor, the resonant capacitor, the switch tube and the third inductor constitute the resonant cavity of the entire circuit topology.

2. The treatment device for radio frequency beauty instrument according to claim 1, characterized in that: The first circuit includes a first resonant capacitor, a first switch tube, a second inductor and a first general capacitor, the second circuit includes a second resonant capacitor, a second switch tube, a fourth inductor and a second general capacitor, the first switch tube and the second switch tube are alternately turned on, and in the process of the first switch tube and the second switch tube being alternately turned on, the composition of the resonant cavity is switched between the third inductor, the capacitor, the first resonant capacitor and the third inductor, the capacitor, and the second resonant capacitor.

3. The treatment device for radio frequency beauty instrument according to claim 1, characterized in that: The high-frequency isolation transformer comprises a magnetic core and a winding. Both the magnetic core and the winding adopt planar inductors. The planar inductors are fixed by stacking multiple layers of different circuit boards with a fixed gap.

4. The treatment device for radio frequency beauty instrument according to claim 1, characterized in that: A DC-isolating capacitor is arranged inside the high-frequency isolation transformer.

5. A radio frequency beauty instrument, comprising: The therapeutic device, therapeutic handle, back plate, therapeutic probe and switch as described in claims 1 to 4 are characterized in that the therapeutic device includes a detachable cold air tank, a control module, a touch screen, a radio frequency power amplifier circuit, an automatic step-up and step-down power supply module, a power supply module and an adapter, the therapeutic device is connected to the proximal end of the therapeutic handle through the adapter, the switch is electrically connected to the control module in the therapeutic device, the therapeutic probe is installed at the distal end of the therapeutic handle, the therapeutic handle includes a handle housing and a handle cable, the handle cable consists of a circuit harness and a cold air pipeline, one end of the cold air pipeline is connected to the cold air tank in the therapeutic device through the adapter, and the other end of the cold air pipeline is connected to the cold air port set in the therapeutic probe, One end of the circuit harness is electrically connected to the control module and the output end of the radio frequency power amplifier circuit through an adapter, and the other end of the circuit harness is connected to the treatment electrode arranged on the treatment probe. The radio frequency power amplifier circuit is a symmetrical series-parallel resonant circuit, and the symmetrical series-parallel resonant circuit includes a high-frequency isolation transformer, a third inductor and a capacitor and a parallel resonant circuit. The input end of the parallel resonant circuit is connected to the output end of the automatic step-up and step-down power supply module. The parallel resonant circuit is composed of a first circuit and a second circuit arranged in parallel. The first circuit and the second circuit both include a general capacitor, a resonant capacitor, a switch tube and an inductor. The capacitor, the general capacitor, the resonant capacitor, the switch tube and the third inductor constitute the resonant cavity of the entire circuit topology.

6. The radio frequency beauty instrument according to claim 5, characterized in that: The cold air tank is connected to the adapter through a pipeline, the control module is electrically connected to the touch screen and the automatic step-up and step-down power supply module, the input end of the RF power amplifier circuit is connected to the output end of the automatic step-up and step-down power supply module, and the output end of the RF power amplifier circuit is connected to the adapter, the first circuit includes a first resonant capacitor, a first switch tube, a second inductor and a first general capacitor, the second circuit includes a second resonant capacitor, a second switch tube, a fourth inductor and a second general capacitor, the first switch tube and the second switch tube are alternately turned on, and in the process of the first switch tube and the second switch tube being alternately turned on, the composition of the resonant cavity is switched between the third inductor, the capacitor, the first resonant capacitor and the third inductor, the capacitor, and the second resonant capacitor.

7. The radio frequency beauty instrument according to claim 6, characterized in that: A DC-isolating capacitor is arranged inside the high-frequency isolation transformer.

8. The radio frequency beauty instrument according to claim 5, characterized in that: The switch is an excitation button arranged on the handle housing or a foot switch directly connected to the control module of the treatment device. The treatment handle also includes a parameter setting component arranged on the handle housing and a control circuit board arranged in the handle housing. The excitation button and the parameter setting component are electrically connected to the control circuit board, and the control circuit board is electrically connected to the control module through the circuit harness.

9. The radio frequency beauty instrument according to claim 5, characterized in that: An insulator is arranged on the treatment probe.

10. The radio frequency beauty instrument according to claim 5, characterized in that: A metal ring is arranged around the treatment electrode.

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