Active sleep cooling equipment

Abstract

The invention discloses an active sleep cooling device, and belongs to the field of intelligent temperature control. According to the equipment, semiconductor chilling plates (20-100 W, COP > = 1.5 and delta T = 25 DEG C) are adopted to form a refrigeration module, the cold end is connected with a circulation pipeline through a buckle type water cooling head, and the hot end is coated with dynamically-adjusted heat-conducting silicone grease (the contact pressure is 0.1-0.3 MPa). The liquid cooling system (the flow is automatically adjusted along with power and temperature difference) is innovatively designed to be in redundancy fit with the air cooling system, and the hot end is less than or equal to 65 DEG C. Non-contact conduction of cooling liquid is achieved through the composite uniform temperature layer (cotton and polyurethane), and the temperature difference gradient smaller than or equal to 2 DEG C / cm is formed. Precise temperature control of + / -0.5 DEG C is achieved based on an STM32 PID control system (the parameter adjustable range Kp is equal to 0.8-1.2), and the temperature is reduced by 7 DEG C or more within 10 minutes. The safety system integrates a condensation sensor (which is triggered for 10 minutes after the humidity is greater than or equal to 70%) and a double-metal protector (cold end lt; 13 DEG C / hot end gt; 65 DEG C), via a solid state relay (in response to lt; and the double protection is realized. The power consumption of the whole machine is smaller than or equal to 120 W, the noise is smaller than or equal to 30 dB (A), the energy efficiency is improved by 50% compared with a traditional scheme, and 72-hour hydrolysis test (the strength is kept to be larger than or equal to 90%) and IP54 certification are passed. The equipment can be integrated on a mattress or a pillow or used as an independent device, is suitable for family sleep optimization, medical care and outdoor scenes, and has remarkable market application value.

Description

[0002] Technical Field The present invention relates to the technical field of intelligent temperature control devices, and specifically to an active sleep cooling device based on semiconductor refrigeration technology, combined with liquid cooling / air cooling heat dissipation and PID algorithm, which is suitable for improving the thermal comfort of the sleep environment, especially for medical care and household scenarios.

[0003] Background Art Traditional cooling devices (such as air conditioners and fans) have the following defects: Noise problem: The operating noise of the compressor or fan interferes with sleep (usually >40 dB), while the noise of this product is less than 30 dB; Insufficient energy efficiency: The refrigeration efficiency (COP) of air conditioners is only 2.0 - 3.0, and local precise temperature control cannot be achieved; Safety risks: Direct contact cooling easily leads to the accumulation of condensed water, posing potential risks of low-temperature burns or electric leakage; Poor dynamic response: It cannot be adjusted in real time according to users' physiological data (such as heart rate and body surface temperature).

[0004] Although existing semiconductor refrigeration devices are small in size and noise-free, they are limited by heat dissipation efficiency and temperature control accuracy. For example: When the temperature difference (ΔT) between the cold end and the hot end exceeds 30 °C, the COP drops sharply to <1.0; Insufficient design of the heat dissipation system easily causes the temperature of the hot end to exceed 70 °C, leading to device aging or even failure.

[0005] Therefore, there is an urgent need for an active sleep cooling solution with high energy efficiency, low noise, and multiple safety protections.

[0006] Summary of the Invention I. Invention Objective To provide a device that realizes precise temperature control, abnormal warning, and non-contact cooling through multi-module collaborative control, and solves the problems of noise, energy efficiency, and safety hazards in traditional technologies.

[0007] II. Technical Solution The present invention consists of the following modules (see Figure 1 ): Semiconductor refrigeration module Core device: TEC1-12706 type refrigeration chip, with a power of 20 - 100 W and COP ≥ 1.5 (ΔT = 25 °C); Cold end connection: Coupled with the PVC circulation pipeline through a snap-on water-cooled head, with a contact area ≥ 80% and a pressure of 0.1 - 0.3 MPa; Hot end heat dissipation: Coated with high thermal conductivity silicone grease (thermal conductivity ≥ 5 W / (m*k), viscosity 2000 - 3000 cp), and the thickness is dynamically adjusted according to the formula d = 0.5 - 0.004P (when P = 100 W, d = 0.1 mm).

[0008] Module heat dissipation system (one of the two must be included) Liquid cooling mode: The first water pump drives the coolant (ethylene glycol aqueous solution, freezing point -20°C) to flow through the plate heat exchanger, and the flow rate is adjusted according to Q1 = 0.2P + 0.1ΔT (ΔT is the temperature difference between the hot end and the environment). Air cooling mode: The standby axial flow fan starts when the liquid cooling fails or ΔT > 30°C, and the wind speed is linearly positively correlated with the hot end temperature.

[0009] Thermal conduction device Structure: The PVC circulation pipeline (coated with 50 - 100μm polyurethane coating) is embedded in the temperature equalizing layer of the thermal insulation device; Circulation control: The second water pump drives the coolant according to Q2 = 0.15P + 0.05ΔT, indirectly contacts the human body through the breathable cotton fabric layer, and realizes local cooling through non-contact convection (temperature difference gradient ≤ 2°C / cm).

[0010] Safety monitoring and alarm system Sensor group: Dew condensation sensor (HIH - 4000), detects the humidity of the pipe wall, triggering condition: humidity ≥ 70% and lasts for 10 minutes; Bimetallic over-temperature protector, action threshold: cold end < 13°C or hot end > 65°C; Body temperature sensor (accuracy ±0.3°C, response time ≤ 3 seconds).

[0011] Actuator: The solid-state relay (response time < 0.3 seconds) cuts off the power supply in case of abnormality, and synchronously pushes the alarm information to the user terminal.

[0012] Thermal insulation device Outer layer: 3 - 5mm composite structure (1 - 3mm cotton fabric + 2mm polyurethane foam), reducing environmental heat interference; Internal temperature equalizing layer: 1 - 2mm cotton fabric, ensuring uniform distribution of cold quantity. Beneficial effects

[0013] Energy efficiency optimization: Through the silicone grease thickness formula and the double water pump flow model, the overall power consumption of the machine ≤ 120W (measured data); Safety protection: Dew condensation and over-temperature double protection mechanisms to prevent condensed water from contacting the human body or the device from overheating; Dynamic response: The PID algorithm controls the body surface temperature fluctuation within ±0.5°C within 10 seconds (test environment: room temperature of 28°C); Comfort improvement: The non-contact cooling design makes the device operation noise ≤ 30dB(A), significantly improving the sleep quality. Description of the drawings

[0014] Figure 1 : Schematic diagram of the device structure (showing the connection relationship of the semiconductor refrigeration chip, heat dissipation system, thermal conduction device and control module); Figure 2: PID control logic block diagram (including temperature acquisition, algorithm operation and power output process); Figure 3 : Alarm system circuit diagram (interlocking circuit of dew sensor, overtemperature protector and solid-state relay); Figure 4 : PVC pipeline human body adaptation design drawing; Figure 5 : Heat dissipation system structure diagram; Figure 6 : Detailed diagram of heat conduction principle;

[0015] Initialization: The user sets the target body temperature (such as 34°C) through the OLED screen, and the microprocessor starts the self-check program; Data acquisition: The body temperature sensor monitors the body surface temperature in real time, and the heart rate sensor detects the user's physiological state; Dynamic adjustment: When the detected body surface temperature > 35°C, the PID algorithm outputs a refrigeration power of P = 80W, and it is calculated that: Q1 = 0.2×80 + 0.1×15 = 17.5L / min, Q2 = 0.15×80 + 0.05×15 = 13.5L / min The cold end temperature drops from 30°C to 26°C within 5 minutes, and the temperature difference gradient is stable at 1.8°C / cm; Abnormal handling: If the hot end temperature rises to 68°C due to a heat dissipation failure, the overtemperature protector triggers the relay to cut off the power, and the APP pushes an "equipment overheat" alarm.

[0016] Example 2: Clinical nursing application Integrate the device into a medical mattress. Under the conditions of an environmental temperature of 30°C and a humidity of 60%: The initial body surface temperature is 38.5°C (simulating a fever patient), and the target temperature is set to 33°C; It cools down to 33.5°C (error +0.5°C) within 10 minutes, the COP is maintained at 1.5, and no condensed water is generated throughout the process.

[0017] Example 3 (Semiconductor refrigeration chip packaging structure) - Package the TEC1-12706 type semiconductor refrigeration chip (refrigeration power 72W) into a copper liquid cooling plate (size 40×40×5mm) through thermal conductive silicone grease (thickness 0.1mm); - The liquid cooling plate and the PVC circulation pipeline (outer diameter 6mm) adopt a quick-release magnetic interface (magnetic field strength 0.25T), and the surface roughness Ra of the contact surface ≤ 1.6μm; - Fill the polyurethane foam layer (thickness 3mm) as the thermal insulation layer Experimental data: - At an environmental temperature of 25°C, the lowest temperature at the cold end is -15°C, and the temperature at the hot end ≤ 45°C (radiator fan speed 2000RPM); - After continuous operation for 500 hours, the pressure attenuation of the magnetic adsorption interface is < 2%.

[0018] Industrial applicability The present invention can be extended and applied to: Household scenarios: As an independent device or embedded in bedding (pillows, mattresses); Medical field: Assisting in antipyretic treatment or post-operative body temperature management; Outdoor equipment: Combined with tents and sleeping bags to improve sleep comfort in high-temperature environments.

[0019] 72-hour continuous operation test: MTBF ≥ 5000 hours, and the strength retention rate of the polyurethane coating after hydrolysis is 92% (ASTM D4306-23A standard); Moisture permeability test: 5020 g / (m 2 ·24 h) (Method B of GB / T 12704-2019), meeting the heat dissipation requirements of the human body.

[0020] COP: Coefficient of performance (cooling capacity / input power); kp, Ti, Td: Proportional coefficient, integral time, and derivative time of the PID algorithm; Q1, Q2: Flow rates of the first and second water pumps (L / min); ΔT: Temperature difference between the hot end and the environment (°C).

[0021] For specific practical applications, the semiconductor refrigeration chip can be encapsulated into an integrated sealed structure design in the heat dissipation system A protective frame is arranged inside the heat dissipation system to form a packaging cavity with the semiconductor refrigeration chip and the heat conduction plate, and sealing materials such as silica gel or epoxy resin are filled to achieve full-wrap sealing The refrigeration chip is wrapped by a one-time foaming process (such as polyurethane foam) to block the heat neutralization between the hot and cold ends; Furthermore, the structure can be optimized, and a magnetic adsorption structure can also be used, such as Embedded annular magnetic part: An annular magnetic part (such as a neodymium iron boron magnet) can be set on the outer or inner circle of the contact surface between the water-cooled head and the semiconductor refrigeration chip to form a closed magnetic circuit to enhance the adsorption force Modular magnetic adsorption interface: The contact surface between the water-cooled head and the semiconductor refrigeration chip is designed as a detachable magnetic adsorption module. For example: The cold end of the semiconductor refrigeration chip is embedded in a magnetic base; A magnetic adsorption block is arranged on the contact surface of the water-cooled head and is quickly adsorbed and fixed by magnetic force.

[0022] In the embodiment, the PVC pipeline can be replaced with flexible materials such as TPU.

Claims

1. An active sleep cooling device, characterized in that: include: The hot end of the semiconductor refrigeration chip is connected to the heat dissipation system through thermal grease, and the cold end is coupled to the heat conduction device through a water cooling head; A heat dissipation system, comprising at least one of a liquid-cooled radiator and an air-cooled radiator, wherein the liquid-cooled radiator comprises a first water pump, a plate heat exchanger and a circulation pipeline; A heat transfer device, composed of a flexible pipe circulation, filled with coolant; An independent circulation module includes a second water pump for driving the coolant to circulate in the heat transfer device; A control module, including a microprocessor, a temperature sensor and a power management module, which adjusts the working state of the cooling module through a PID algorithm, and the control module also includes a user interface and a wireless communication module; Monitoring module, including temperature sensor and heart rate sensor, provides real-time feedback of user physiological data; Alarm system, used to trigger reminders when abnormalities are detected; The thermal insulation device and the flexible circulation pipeline of the heat conduction device are embedded in the temperature-averaging layer of the thermal insulation device.

2. The device according to claim 1, characterized in that: The hot end of the semiconductor refrigeration plate is in direct contact with the heat dissipation system through silicone grease, and the cold end is connected to the water cooling head of the heat conduction device through a buckle structure. The silicone grease parameters meet the following requirements: Thermal conductivity ≥5 W / ( ) Viscosity 2000-3000 cP The coating thickness d (mm) is adapted to the cooling power P (W) so that when P is in the range of 20-100W, the hot end temperature T_hot ≤ 50°C and the cold end temperature difference ΔT ≥ 20°C The contact surface parameters are: Contact area ratio ≥80% Pressure value 0.1-0.3 MPa.

3. The device according to claim 1, characterized in that: The heat preservation device comprises: Outer insulation layer: thickness 3-5 mm, made of polyurethane foam; Internal temperature equalizing layer: thickness 1-2 mm, made of cotton fabric; The outer surface of the PVC circulation pipeline is provided with a polyurethane coating with a coating thickness of 50-100 μm; The outer layer of polyurethane foam (thermal conductivity ≤ 0.03 W / m·K) and the inner layer of cotton fabric (moisture permeability ≥ 5000 g / m²·24h) are combined to achieve the dual functions of heat preservation and moisture permeability, making the temperature difference on the equipment surface ≤ ±0.5℃.

4. The device according to claim 1, characterized in that: The heat transfer device is configured as follows: after the coolant is cooled by the cold end of the semiconductor refrigeration plate, it is transported to the temperature-averaging layer of the heat preservation device by the second water pump, and indirectly contacts the human body through the breathable fabric layer, and transfers heat by convection, thereby achieving local cooling of the human body through non-contact heat transfer.

5. The device according to claim 1, characterized in that: The refrigeration efficiency of the semiconductor refrigeration sheet satisfies: COP ≥ 0.5, where ΔT = Thot − Tambient = 25 °C.

6. The device according to claim 1, characterized in that: a) The flow rate of the first water pump is adjusted according to the formula \( Q_1 = 0.2P + 0.1\Delta T \); b) The flow rate of the second water pump is adjusted according to the formula \( Q_2 = 0.15P + 0.05\Delta T \); in: Where: \( Q_1, Q_2 \): flow rate (L / min); \( P \): cooling chip power (W); \( \Delta T \): temperature difference between hot end and environment (℃).

7. The device according to claim 1, characterized in that: The PID algorithm parameters are configured as follows: \[ = 0.8-1.2, \quad = 30-60 \, \text{s}, \quad = 5-10 \, \text{s} \], The above parameters can be used to control the system temperature fluctuation within the range of ±0.5℃.

8. The device according to claim 1, characterized in that: The monitoring module also includes a body temperature sensor, whose parameters are: Response time ≤ 3 seconds Measuring accuracy: ±0.3℃.

9. The device according to claim 1, characterized in that: The outer surface of the equipment is provided with a polyurethane composite coating, and the parameters meet the following requirements: Thickness: 80±20 μm Moisture permeability ≥5000 g / (m²·24h) (Test conditions: 37°C, humidity 50%, GB / T 12704-2019 Method B) Hydrolysis resistance: Strength retention rate after 72 hours of hydrolysis test ≥90% (ASTM D4306-23).

10. The device according to claim 1, characterized in that: The alarm system comprises: a) Dew sensor is arranged on the surface of the flexible circulation pipe to detect condensation. When the dew sensor detects condensation on the pipe wall and the ambient humidity is ≥70% for 10 minutes, an alarm is triggered. ; b) Humidity sensor; c) Bimetallic over-temperature protector, the triggering conditions are: The cold end temperature is less than 13°C and the ambient humidity is ≥70%; Hot end temperature>65℃; c) Solid state relay, response time<0.3s to cut off power supply.

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