Refrigeration sheet temperature control circuit for intense pulsed light therapeutic instrument and intense pulsed light therapeutic instrument

Abstract

The utility model discloses a refrigeration sheet temperature control circuit and an intense pulsed light therapeutic instrument. The temperature control circuit comprises a cold and hot surface switching circuit, the cold and hot surface switching circuit comprises a first branch and a second branch which are arranged in parallel, the first branch comprises a first controlled switch and a first change-over switch, and the second branch comprises a second controlled switch and a second change-over switch; the control ends of the first controlled switch and the second controlled switch receive cold and hot surface switching signals; each change-over switch comprises a first output end and a second output end, one is connected with a power supply, and the other is grounded; fixed ends of the two change-over switches are respectively connected with positive and negative electrodes of the refrigeration sheet; the cold and hot surface switching signal comprises a forward direction cold and hot surface signal and a reverse direction cold and hot surface signal, and the first controlled switch control end and the second controlled switch control end are kept cut off after receiving one of the signals, so that the first change-over switch and the second change-over switch are kept communicated with the first output end; the first controlled switch control end and the second controlled switch control end are switched on when receiving the other one, so that the first change-over switch and the second change-over switch are switched to be communicated with the second output end. The refrigeration sheet temperature control circuit can prevent the crystal from frosting due to too low temperature.

Description

Technical Field

[0001] The utility model relates to the technical field of intense pulsed light therapy instruments, in particular to a thermoelectric cooler temperature control circuit for an intense pulsed light therapy instrument and an intense pulsed light therapy instrument with the temperature control circuit. Background Art

[0002] Intense pulsed light, abbreviated as IPL, also known as photons, is a multi-color pulsed light source released by a high-energy xenon lamp under the action of tens of thousands of volts of high voltage. Intense pulsed light is mainly used for treating skin aging, and is also widely used for treating various pigmentary skin diseases, vascular skin diseases, hirsutism and even inflammatory skin diseases (such as acne and rosacea, etc.). At present, many manufacturers on the market have launched some intense pulsed light therapy instruments for treating related skin problems. The process of using an intense pulsed light therapy instrument is as follows: the treatment head of the intense pulsed light therapy instrument is closely attached to the skin, and light waves of a certain intensity are output at preset time intervals. During this process, the treatment head of the intense pulsed light therapy instrument can be operated to move on various parts of the skin, so that the light waves act on various parts of the skin to be treated to achieve treatment. The light waves output by the intense pulsed light therapy instrument have a high intensity and are accompanied by high heat, which is easy to burn the skin. For this reason, most intense pulsed light therapy instruments are provided with a thermoelectric cooler and a crystal at the treatment head. During the treatment process, the thermoelectric cooler continuously cools to lower the temperature of the crystal, so that the crystal can perform cold compress on the user's skin to prevent the skin from being burned. After the intense pulsed light therapy instrument is turned on, the thermoelectric cooler will start to cool. Sometimes, after the operator turns on the intense pulsed light therapy instrument, due to certain reasons such as the user suddenly having a problem to consult or having other urgent work to deal with, etc., the operator may not immediately start using it to treat the user's skin. At this time, since the intense pulsed light therapy instrument does not emit light, that is, the treatment head does not generate high heat, and the thermoelectric cooler has been cooling to continuously lower the temperature of the crystal, it will cause the crystal to frost due to too low a temperature. Summary of the Invention

[0003] The purpose of the utility model is to provide a thermoelectric cooler temperature control circuit for an intense pulsed light therapy instrument and a hardware connection structure of an intense pulsed light therapy instrument for software personnel to program, and the thermoelectric cooler temperature control circuit can prevent the crystal from frosting due to too low a temperature.

[0004] In order to achieve the above purpose, the utility model provides a thermoelectric cooler temperature control circuit for an intense pulsed light therapy instrument as follows:

[0005] It includes a thermoelectric cooler, a hot and cold surface switching circuit and a crystal for performing cold compress on the user's skin at the treatment head of the intense pulsed light therapy instrument. The normal cold surface of the thermoelectric cooler is closely attached to the crystal to lower the temperature of the crystal. The output end of the hot and cold surface switching circuit is connected to the positive and negative poles of the thermoelectric cooler, and the input end of the hot and cold surface switching circuit receives a hot and cold surface switching signal output by the MCU of the intense pulsed light therapy instrument;

[0006] The hot and cold surface switching circuit includes a first branch and a second branch in parallel. The input ends of the first branch and the second branch are connected, and the output ends of the first branch and the second branch are respectively connected to the positive and negative electrodes of the thermoelectric cooler; the first branch includes a first controlled switch and a first switching switch connected in series, and the second branch includes a second controlled switch and a second switching switch connected in series;

[0007] The control ends of the first controlled switch and the second controlled switch serve as the input ends of the first branch and the second branch respectively, and receive the hot and cold surface switching signal output by the MCU of the intense pulsed light therapy instrument through the input end of the hot and cold surface switching circuit;

[0008] Each switching switch includes a first output end and a second output end. Among the first output end and the second output end, one is connected to the power supply and the other is grounded; the fixed ends of the two switching switches serve as the output ends of the hot and cold surface switching circuit and are respectively connected to the positive and negative electrodes of the thermoelectric cooler;

[0009] The hot and cold surface switching signal includes two types: a positive hot and cold surface signal and a negative hot and cold surface signal. Among the positive hot and cold surface signal and the negative hot and cold surface signal: when the control ends of the first controlled switch and the second controlled switch receive one of them, the first and second controlled switches remain cut off, so that the first and second switching switches remain connected to the first output end; when the control ends of the first controlled switch and the second controlled switch receive the other, the first and second controlled switches are turned on, so that the first and second switching switches switch from connecting to the first output end to connecting to the second output end, thereby reversing the current polarity of the positive and negative electrodes of the thermoelectric cooler.

[0010] Furthermore:

[0011] An optocoupler U35 is connected in series in the hot and cold surface switching circuit. It is connected to the input ends of the first branch and the second branch. The control ends of the first controlled switch and the second controlled switch specifically receive the positive hot and cold surface signal or the negative hot and cold surface signal output by the MCU of the intense pulsed light therapy instrument through the optocoupler U35.

[0012] Furthermore: the positive hot and cold surface signal is a high-level signal, and the negative hot and cold surface signal is a low-level signal; when the input end of the optocoupler U35 receives the positive hot and cold surface signal, the output end does not output an electrical signal, so that the first and second controlled switches remain cut off; when the input end of the optocoupler U35 receives the negative hot and cold surface signal, the output end outputs an electrical signal, so that the first and second controlled switches are turned on.

[0013] Furthermore, a current-limiting resistor R165 is connected to the input end of the optocoupler U35, and receives the positive hot and cold surface signal or the negative hot and cold surface signal output by the MCU of the intense pulsed light therapy instrument through the current-limiting resistor R165.

[0014] Furthermore, the connection point between the current-limiting resistor R165 and the input end of the optocoupler U35 is connected to the power supply through a resistor R164.

[0015] Further, the first and second controlled switches are triodes, and / or the first and second switching switches are relays.

[0016] Further, it includes a PWM control circuit. The input end of the PWM control circuit receives the PWM signal of the thermoelectric cooler intensity control pulse output by the MCU of the intense pulsed light treatment instrument, and the output end is connected to the control end of the thermoelectric cooler.

[0017] Further: The PWM control circuit includes a triode Q10, an optocoupler U1, and a MOS transistor; the base of the triode Q10 receives the PWM signal of the thermoelectric cooler intensity control pulse output by the MCU of the intense pulsed light treatment instrument through the input end of the PWM control circuit. The collector of the triode Q10 is connected to the power supply, and the emitter is connected to the input end of the optocoupler U1; the output end of the optocoupler U1 is connected to the gate of the MOS transistor. The drain of the MOS transistor is grounded, and the source is used as the output end of the PWM control circuit and is connected to the control end of the thermoelectric cooler.

[0018] Further: The connection point between the emitter of the triode Q10 and the input end of the optocoupler U1 is grounded through a resistor R129. The base is grounded through a diode D8 and a resistor R27 respectively, and the collector is connected to the power supply through a current-limiting resistor R39; the gate of the MOS transistor is connected across to the source through a resistor R99, and the connection point between the source and the resistor R99 is grounded through a resistor R47.

[0019] The present utility model also provides an intense pulsed light treatment instrument, which includes an MCU, an intense pulsed light output control circuit, and a treatment head. The treatment head is provided with a xenon lamp. The MCU is connected to the input end of the intense pulsed light output control circuit, and the output end of the intense pulsed light output control circuit is connected to the xenon lamp in the treatment head. It includes the thermoelectric cooler temperature control circuit for the intense pulsed light treatment instrument as described above. The input ends of the hot and cold surface switching circuit and the PWM control circuit of the thermoelectric cooler temperature control circuit are both connected to the MCU. The thermoelectric cooler and the crystal of the thermoelectric cooler temperature control circuit are arranged in the treatment head; it includes a temperature sensor for detecting the temperature of the crystal, and the temperature sensor is connected to the MCU.

[0020] The thermoelectric cooler temperature control circuit provided by the present utility model is applied to a high-intensity pulsed light therapeutic apparatus. Among them, a crystal is arranged at the treatment head of the high-intensity pulsed light therapeutic apparatus to perform cold compress on the user's skin during the treatment process. The first and second controlled switches of the thermoelectric cooler temperature control circuit can control the first and second switching switches to switch the output terminals they are connected to according to the received hot and cold surface switching signals, so as to control the switching of the hot and cold surfaces of the thermoelectric cooler, and can briefly heat the crystal when the temperature of the crystal is too low to prevent the crystal from frosting due to too low temperature. The specific process is as follows: Under normal circumstances, the MCU of the high-intensity pulsed light therapeutic apparatus outputs a positive hot and cold surface signal. When the first and second controlled switches receive the positive hot and cold surface signal, they remain cut off, so that the first and second switching switches remain connected to the first output terminal, and the thermoelectric cooler is in the positive hot and cold surface state, that is, the surface of the thermoelectric cooler in contact with the crystal is the cold surface, and the other surface is the hot surface. The cold surface of the thermoelectric cooler cools the crystal to perform cold compress on the user's skin during the treatment process; when the temperature of the crystal is too low, the MCU of the high-intensity pulsed light therapeutic apparatus outputs a reverse hot and cold surface signal. When the first and second controlled switches receive the reverse hot and cold surface signal, they conduct, so that the first and second switching switches switch from being connected to the first output terminal to being connected to the second output terminal, so that the positive and negative current polarities of the thermoelectric cooler are reversed, and the thermoelectric cooler is switched to the reverse hot and cold surface state, that is, the surface of the thermoelectric cooler in contact with the crystal is the hot surface, and the other surface is the cold surface. The thermoelectric cooler heats the crystal to prevent it from frosting due to too low temperature; after heating for a period of time, the MCU of the high-intensity pulsed light therapeutic apparatus outputs a positive hot and cold surface signal. When the first and second controlled switches receive the positive hot and cold surface signal again, they return to cut off, so that the first and second switching switches return from being connected to the second output terminal to being connected to the first output terminal, and the thermoelectric cooler is in the positive hot and cold surface state, that is, the surface of the thermoelectric cooler in contact with the crystal is the cold surface, and the other surface is the hot surface. The thermoelectric cooler cools the crystal.

[0021] The present utility model also provides a hardware connection structure of a intense pulsed light treatment instrument. After a software engineer programs the MCU of the intense pulsed light treatment instrument, the MCU realizes the following control functions: In the normal working state, the MCU of the intense pulsed light treatment instrument controls the treatment head to emit light at fixed time intervals to treat the user's skin. After the intense pulsed light treatment instrument is powered on, the MCU outputs a positive cold and hot surface signal. When the first and second controlled switches receive the positive cold and hot surface signal, they remain cut off, so that the first and second switching switches remain connected to the first output terminal, and the refrigeration chip is in the positive cold and hot surface state, that is, the side of the refrigeration chip contacting the crystal is the cold surface, and the other side is the hot surface. The refrigeration chip cools the crystal to perform cold compress on the user's skin during the treatment process. If the intense pulsed light treatment instrument has not been used for a long time after being powered on, that is, it has not entered the normal working state, since the intense pulsed light treatment instrument does not emit light, that is, the treatment head does not generate high heat, the temperature of the crystal will become lower and lower. If the MCU of the intense pulsed light treatment instrument monitors through the temperature sensor that the temperature of the crystal is too low and may frost, it will output a reverse cold and hot surface signal. When the first and second controlled switches receive the reverse cold and hot surface signal, they conduct, so that the first and second switching switches switch from connecting to the first output terminal to connecting to the second output terminal, thereby reversing the positive and negative current polarities of the refrigeration chip, making the refrigeration chip switch to the reverse cold and hot surface state, that is, the side of the refrigeration chip contacting the crystal is the hot surface, and the other side is the cold surface. The refrigeration chip heats the crystal to prevent it from frosting due to too low temperature; after heating for a short period of time, such as 10 s, the MCU of the intense pulsed light treatment instrument resumes outputting the positive cold and hot surface signal. When the first and second controlled switches receive the positive cold and hot surface signal, they resume cut off, so that the first and second switching switches resume from connecting to the second output terminal to connecting to the first output terminal, and the refrigeration chip is in the positive cold and hot surface state, that is, the side of the refrigeration chip contacting the crystal is the cold surface, and the other side is the hot surface. The refrigeration chip cools the crystal. Description of the Drawings

[0022] Figure 1 is the circuit schematic diagram of the cold and hot surface switching circuit of the refrigeration chip temperature control circuit for the intense pulsed light treatment instrument.

[0023] Figure 2 is the circuit schematic diagram of the PWM control circuit of the refrigeration chip temperature control circuit for the intense pulsed light treatment instrument. Detailed Embodiments

[0024] The following further details the present invention in conjunction with specific embodiments.

[0025] The intense pulsed light therapy instrument includes an MCU (not shown), an intense pulsed light output control circuit (not shown), and a treatment head (not shown). The treatment head is provided with a xenon lamp (not shown). The MCU is connected to the input end of the intense pulsed light output control circuit, and the output end of the intense pulsed light output control circuit is connected to the xenon lamp in the treatment head. In the normal working state, the MCU of the intense pulsed light therapy instrument controls the xenon lamp in the treatment head to emit light at fixed time intervals through the intense pulsed light output control circuit to treat the user's skin. The above is the circuit structure of the inherent function of the intense pulsed light therapy instrument, which will not be described in detail in this embodiment. Based on the above circuit structure of the inherent function, the intense pulsed light therapy instrument of this embodiment further includes a thermoelectric cooler temperature control circuit, which includes a thermoelectric cooler, a crystal, a hot and cold surface switching circuit as shown in Figure 1 and a PWM control circuit as shown in Figure 2 . The input ends of the hot and cold surface switching circuit and the PWM control circuit are both connected to the MCU. The crystal is arranged at the treatment head of the intense pulsed light therapy instrument. The constant cold surface of the thermoelectric cooler is closely attached to the crystal to cool the crystal so that the crystal can perform cold compress on the user's skin. The intense pulsed light therapy instrument also includes a temperature sensor, which is connected to the MCU. The MCU monitors the temperature value of the crystal through the temperature sensor, and accordingly controls the hot and cold surface switching circuit to switch the hot and cold surfaces of the thermoelectric cooler or controls the PWM control circuit to adjust the working power of the thermoelectric cooler. The detailed structures of the hot and cold surface switching circuit and the PWM control circuit will be described in detail below.

[0026] As shown in Figure 1 , the hot and cold surface switching circuit includes a first branch 1 and a second branch 2 arranged in parallel. The first branch 1 includes a triode Q13 as the first controlled switch and a relay J1 as the first switching switch, and the triode Q13 and the relay J1 are connected. The second branch 2 includes a triode Q15 as the second controlled switch and a relay J2 as the second switching switch, and the triode Q15 and the relay J2 are connected. The control ends (i.e., the bases) of the triode Q13 and the triode Q15 serve as the input end of the first branch 1 and the input end of the second branch 2 respectively, and receive the hot and cold surface switching signal output by the MCU of the intense pulsed light therapy instrument through the input end of the hot and cold surface switching circuit (i.e., the 12V10ARELAY port in Figure 1 ). Each of the relays J1 and J2 includes a first output end (the 1st pin in Figure 1 ) and a second output end (the 5th pin in Figure 1 ). The first output end is connected to the power supply (i.e., connected to the VCC24V COLD power supply port of Figure 1 ), and the second output end is grounded (i.e., connected to the IRFB3607_D grounding port of Figure 1 ). The fixed ends of the two relays J1 and J2 ( Figure 1The 3rd pin in ) is used as the output terminal of the hot and cold surface switching circuit and is respectively connected to the positive and negative electrodes of the thermoelectric cooler. Specifically, the 3rd pin of relay J1 is connected to the COLD+ port of the thermoelectric cooler (under normal circumstances, the COLD+ port is connected to 24V, which is the positive electrode of the thermoelectric cooler), and the 3rd pin of relay J3 is connected to the COLD- port of the thermoelectric cooler (under normal circumstances, the COLD- port is grounded and is the negative electrode of the thermoelectric cooler). The hot and cold surface switching circuit includes an optocoupler U35 provided on the main circuit, which is connected to the input terminals of the first branch and the second branch. The bases of transistor Q13 and transistor Q15 are specifically connected to the input terminal of the hot and cold surface switching circuit (i.e., Figure 1 the 12V10A RELAY port in ), that is, receive the hot and cold surface switching signal output by the MCU of the intense pulsed light therapeutic instrument through optocoupler U35. The input terminal of optocoupler U35 is connected with a current-limiting resistor R165, and is connected to the input terminal of the hot and cold surface switching circuit (i.e., Figure 1 the 12V10A RELAY port in ) through current-limiting resistor R165. The connection point between current-limiting resistor R165 and the input terminal of optocoupler U35 is connected to the power supply through resistor R164.

[0027] The hot and cold surface switching signal includes two types: the forward hot and cold surface signal and the reverse hot and cold surface signal. The forward hot and cold surface signal is a high-level signal, and the reverse hot and cold surface signal is a low-level signal. Under normal working conditions, the MCU of the intense pulsed light therapy instrument controls the xenon lamp of the treatment head to emit light at a fixed time interval through the intense pulsed light output control circuit to treat the user's skin. After the intense pulsed light therapy instrument is powered on, the MCU will output a forward hot and cold surface signal, that is, output a high-level signal. When the input terminal of optocoupler U35 receives a high level, its output terminal does not output an electrical signal. The bases of transistor Q13 and transistor Q15 are connected to the output terminal of optocoupler U35. Since optocoupler U35 does not output an electrical signal, the bases of transistor Q13 and transistor Q15 remain at a low level, so transistors Q13 and Q15 remain cut off, making the fixed terminals of relays J1 and J2 remain connected to the first output terminal (pin 1). In this way, the COLD+ port of the thermoelectric cooler is connected to 24V and the COLD- port is grounded. The thermoelectric cooler is in the forward hot and cold surface state, that is, the side of the thermoelectric cooler in contact with the crystal is the cold surface and the other side is the hot surface. The thermoelectric cooler cools the crystal to perform cold compress on the user's skin during the treatment. If the intense pulsed light therapy instrument has not been used for a long time after being powered on, that is, it has not entered the normal working state, since the intense pulsed light therapy instrument does not emit light, that is, the treatment head does not generate high heat, the temperature of the crystal will become lower and lower. If the MCU of the intense pulsed light therapy instrument monitors through the temperature sensor that the temperature of the crystal is too low and may frost, it will output a reverse hot and cold surface signal, that is, output a low level. When the input terminal of optocoupler U35 receives a low-level signal, its output terminal outputs an electrical signal. The bases of transistor Q13 and transistor Q15 are connected to the output terminal of optocoupler U35. Since optocoupler U35 normally outputs an electrical signal, the bases of transistor Q13 and transistor Q15 become high levels, so transistors Q13 and Q15 conduct, causing relays J1 and J2 to act. Their fixed terminals switch from connecting to the first output terminal (pin 1) to connecting to the second output terminal (pin 5), thereby reversing the polarity of the positive and negative currents of the thermoelectric cooler, that is, the COLD+ port of the thermoelectric cooler is changed to be grounded (the COLD+ port becomes the negative pole) and the COLD- port is changed to be connected to 24V (the COLD- port becomes the positive pole), making the thermoelectric cooler switch to the reverse hot and cold surface state, that is, the side of the thermoelectric cooler in contact with the crystal is the hot surface and the other side is the cold surface. In this way, the thermoelectric cooler will heat the crystal to prevent it from frosting due to too low temperature.Generally, it only needs to be heated for a short period of time to increase the temperature of the crystal and achieve the effect of preventing frosting. Therefore, after the intense pulsed light therapy instrument in this embodiment is heated for 10 s, the MCU automatically resumes outputting the forward cold and hot surface signal, that is, outputting a high-level signal. When the input end of optocoupler U35 receives the high-level signal, the output end does not output an electrical signal. The bases of triode Q13 and triode Q15 are connected to the output end of optocoupler U35. Since optocoupler U35 does not output an electrical signal, the bases of triode Q13 and triode Q15 remain at a low level, so triodes Q13 and Q15 resume to remain cut off, and the fixed ends of relays J1 and J2 resume to remain connected to the first output end (pin 1). In this way, the COLD+ port of the thermoelectric cooler resumes to be connected to 24V and the COLD- port resumes to be grounded. The thermoelectric cooler is in the forward cold and hot surface state, that is, the surface of the thermoelectric cooler in contact with the crystal is the cold surface and the other surface is the hot surface, and the thermoelectric cooler cools the crystal.

[0028] Non-preferably, in other embodiments, the first output end (pin 1) of relays J1 and J2 can be changed to be grounded and the second output end (pin 5) can be changed to be connected to the power supply. Correspondingly, the forward cold and hot surface signal is changed to a low-level signal, and the reverse cold and hot surface signal is changed to a high-level signal.

[0029] As Figure 2 shown, the PWM control circuit includes triode Q10, optocoupler U1, and MOS transistor Q11. The base of triode Q10 receives the PWM signal of the thermoelectric cooler intensity control pulse output by the MCU of the intense pulsed light therapy instrument through the input end of the PWM control circuit (that is, the Figure 2 COLD_CONTROL port in). The collector of triode Q10 is connected to the power supply and the emitter is connected to the input end of optocoupler U1. Preferably, the base of triode Q10 is specifically connected to the input end of the PWM control circuit (that is, the Figure 2 COLD_CONTROL port in) through the capacitor C11 and resistor R35 connected in series. The output end of optocoupler U1 is connected to the gate of the MOS transistor. The drain of the MOS transistor is grounded and the source is used as the output end of the PWM control circuit (that is, the Figure 2The COLD CIRCUIT port therein) is connected to the control terminal of the thermoelectric cooler. The connection point between the emitter of transistor Q10 and the input terminal of optocoupler U1 is grounded through resistor R129, the base is grounded through diode D8 and resistor R27 respectively, and the collector is connected to the power supply through current-limiting resistor R39. The gate of the MOS transistor is connected across to the source through resistor R99, and the connection point between the source and resistor R99 is grounded through resistor R47. After the intense pulsed light therapeutic apparatus is powered on, the MCU outputs a PWM signal of the thermoelectric cooler intensity control pulse to start the thermoelectric cooler. Specifically: The COLD_CONTROL port receives the PWM signal of the thermoelectric cooler intensity control pulse. This PWM signal is transmitted to the base of transistor Q10 through resistor R35 and capacitor C11. Transistor Q10 conducts cyclically, causing optocoupler U1 to conduct cyclically, driving MOS transistor Q11 to conduct cyclically. MOS transistor Q11 outputs a signal to the control terminal of the thermoelectric cooler cyclically, thereby driving the thermoelectric cooler to start working. The intense pulsed light therapeutic apparatus can control the voltage level output by MOS transistor Q11 by outputting PWM signals of the thermoelectric cooler intensity control pulse with different duty cycles, thereby adjusting the working power of the thermoelectric cooler (if the thermoelectric cooler is in the state of cooling the crystal, it is to adjust the cooling intensity of the thermoelectric cooler; if the thermoelectric cooler is in the state of heating the crystal, it is to adjust the heating intensity of the thermoelectric cooler). For example, during the treatment of the user by the intense pulsed light therapeutic apparatus, when the thermoelectric cooler cools the crystal, the MCU monitors through the temperature sensor that the temperature value of the crystal is relatively high (indicating that the achieved cold compress effect is not good). The MCU then outputs a PWM signal of the thermoelectric cooler intensity control pulse with a higher duty cycle, increasing the conduction duration of MOS transistor Q11, thereby increasing the working power of the thermoelectric cooler, that is, increasing the cooling intensity of the thermoelectric cooler, further reducing the temperature value of the crystal, so that the crystal can better perform cold compress on the user's skin. If the MCU monitors through the temperature sensor that the temperature of the crystal is too low, then the MCU outputs a PWM signal of the thermoelectric cooler intensity control pulse with a lower duty cycle, reducing the conduction duration of MOS transistor Q11, thereby reducing the working power of the thermoelectric cooler, that is, reducing the cooling intensity of the thermoelectric cooler, causing the temperature value of the crystal to rise slightly. The MCU of the intense pulsed light therapeutic apparatus can control the PWM signal of the thermoelectric cooler intensity control pulse output according to the temperature value detected by the temperature sensor to achieve closed-loop control. Suppose the MCU detects through the temperature sensor that the crystal has reached the frosting temperature, and the thermoelectric cooler is switched to the state of heating the crystal through the hot and cold surface switching circuit. The MCU outputs a PWM signal of the thermoelectric cooler intensity control pulse with a preset duty cycle to control the thermoelectric cooler to heat and defrost the crystal. If the temperature of the crystal rises too slowly and the defrosting effect is not ideal, the MCU outputs a PWM signal of the thermoelectric cooler intensity control pulse with a higher duty cycle, increasing the conduction duration of MOS transistor Q11, thereby increasing the working power of the thermoelectric cooler, that is, increasing the heating intensity of the thermoelectric cooler, further increasing the temperature value of the crystal, which can enhance the defrosting effect of the crystal.On the contrary, if the crystal temperature rises too fast, the MCU outputs a PWM signal for controlling the intensity of the thermoelectric cooler with a lower duty cycle, reducing the conduction duration of the MOS transistor Q11, thereby reducing the working power of the thermoelectric cooler, that is, reducing the heat generation intensity of the thermoelectric cooler, so that the crystal temperature rises slowly.

[0030] As described above, only the embodiments of the present invention are provided, and the scope of patent protection is not limited thereby. Those skilled in the art make non-substantive changes or substitutions based on the present invention, and still fall within the scope of patent protection.

Claims

1. A temperature control circuit for a refrigeration sheet of an intense pulsed light therapy device, characterized in that: It includes a cooling sheet, a hot and cold surface switching circuit, and a crystal used for applying cold compress to the user's skin at the treatment head of an intense pulsed light therapy device. The normally cold surface of the cooling sheet is in close contact with the crystal to cool the crystal. The output end of the hot and cold surface switching circuit is connected to the positive and negative electrodes of the cooling sheet. The input end of the hot and cold surface switching circuit receives a hot and cold surface switching signal output by the MCU of the intense pulsed light therapy device. The hot and cold surface switching circuit comprises a first branch (1) and a second branch (2) in parallel, wherein the first branch input end is connected to the second branch input end, and the first branch output end and the second branch output end are respectively connected to the positive and negative electrodes of the refrigeration plate; the first branch comprises a first controlled switch and a first switching switch connected to each other, and the second branch comprises a second controlled switch and a second switching switch connected to each other; The first controlled switch control end and the second controlled switch control end serve as the first branch (1) input end and the second branch (2) input end respectively, and receive the hot and cold surface switching signal output by the MCU of the intense pulsed light therapy device via the hot and cold surface switching circuit input end; Each switching switch includes a first output terminal and a second output terminal, one of which is connected to a power source and the other is grounded; the fixed ends of the two switching switches are connected to the positive and negative electrodes of the cooling plate as the output ends of the cold and hot surface switching circuit respectively; The hot and cold surface switching signals include two types: forward hot and cold surface signals and reverse hot and cold surface signals. Among the forward hot and cold surface signals and the reverse hot and cold surface signals: when the first controlled switch control end and the second controlled switch control end receive one of them, the first and second controlled switches remain cut off, so that the first and second switching switches remain connected to the first output end; when the first controlled switch control end and the second controlled switch control end receive the other one, the first and second controlled switches are turned on, so that the first and second switching switches switch from connecting to the first output end to connecting to the second output end, thereby reversing the polarity of the positive and negative currents of the refrigeration plate.

2. The temperature control circuit of the refrigeration plate for the intense pulsed light therapy apparatus as claimed in claim 1, characterized in that: The hot and cold surface switching circuit is connected in series with an optocoupler U35, which connects the first branch input terminal and the second branch input terminal. The first controlled switch control terminal and the second controlled switch control terminal specifically receive the forward hot and cold surface signal or the reverse hot and cold surface signal output by the MCU of the intense pulsed light therapy device through the optocoupler U35.

3. The temperature control circuit of the refrigeration plate for the intense pulsed light therapy apparatus as claimed in claim 2, characterized in that: The positive hot and cold surface signals are high-level signals, and the negative hot and cold surface signals are low-level signals; when the input end of the optocoupler U35 receives the positive hot and cold surface signals, the output end does not output an electrical signal, thereby keeping the first and second controlled switches cut off; when the input end of the optocoupler U35 receives the negative hot and cold surface signals, the output end outputs an electrical signal, thereby turning on the first and second controlled switches.

4. The refrigeration plate temperature control circuit for an intense pulsed light therapy apparatus as claimed in claim 3, characterized in that: The input end of the optocoupler U35 is connected to the current limiting resistor R165, and receives the forward hot and cold surface signal or the reverse hot and cold surface signal output by the MCU of the intense pulsed light therapy device through the current limiting resistor R165.

5. The temperature control circuit of the refrigeration plate for the intense pulsed light therapy apparatus as claimed in claim 4, characterized in that: The junction between the current limiting resistor R165 and the input end of the optocoupler U35 is connected to the power supply through the resistor R164.

6. The refrigeration plate temperature control circuit for an intense pulsed light therapy apparatus as claimed in claim 1, characterized in that: The first and second controlled switches are triodes, and / or the first and second switching switches are relays.

7. The refrigeration plate temperature control circuit for an intense pulsed light therapy apparatus as claimed in claim 1, characterized in that: It comprises a PWM control circuit, the input end of which receives a cooling plate intensity control pulse PWM signal output by the MCU of the intense pulse light therapy device, and the output end is connected to the cooling plate control end.

8. The temperature control circuit of the refrigeration plate for the intense pulsed light therapy apparatus as claimed in claim 7, characterized in that: The PWM control circuit includes a transistor Q10, an optocoupler U1 and a MOS tube; the base of the transistor Q10 receives the cooling plate intensity control pulse PWM signal output by the MCU of the intense pulsed light therapy device through the input end of the PWM control circuit, the collector of the transistor Q10 is connected to the power supply and the emitter is connected to the input end of the optocoupler U1; the output end of the optocoupler U1 is connected to the gate of the MOS tube, the drain of the MOS tube is grounded and the source is connected to the cooling plate control end as the output end of the PWM control circuit.

9. The refrigeration plate temperature control circuit for an intense pulsed light therapy apparatus as claimed in claim 8, characterized in that: The junction between the emitter of transistor Q10 and the input terminal of optocoupler U1 is grounded through resistor R129, the base is grounded through diode D8 and resistor R27 respectively, and the collector is connected to the power supply through current limiting resistor R39; the gate of the MOS tube is connected to the source through resistor R99, and the junction between the source and resistor R99 is grounded through resistor R47.

10. An intense pulsed light therapy device, comprising an MCU, an intense pulsed light control circuit and a treatment head, wherein the treatment head is provided with a xenon lamp, the MCU is connected to an input end of the intense pulsed light control circuit, and an output end of the intense pulsed light control circuit is connected to the xenon lamp in the treatment head, wherein: It comprises a refrigeration plate temperature control circuit for an intense pulsed light therapy device as described in any one of claims 1 to 9, the input ends of the hot and cold surface switching circuit and the PWM control circuit of the refrigeration plate temperature control circuit are both connected to the MCU, and the refrigeration plate and crystal of the refrigeration plate temperature control circuit are arranged in the treatment head; it comprises a temperature sensor for detecting the temperature of the crystal, and the temperature sensor is connected to the MCU.

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