Cold Water Mat System Using Heat Pipe and Control Method Thereof

Abstract

The present invention relates to a cold water mat system using heat pipes. A first fluid circulating through the mat absorbs the user's body heat and transfers it to a water block, and the heat pipe transfers that heat to a heat dissipation member coupled to a heat dissipation section, thereby releasing it to the outside. In one embodiment, an evaporation medium disposed adjacent to the heat dissipation member evaporates a second fluid physically separated from the first fluid, and cools the heat dissipation member and the heat dissipation section of the heat pipe using the latent heat of evaporation, thereby achieving cooling lower than the external air temperature. At this time, the heat dissipation member responsible for heat transfer and the evaporation medium responsible for evaporation are separated by function and optimized using low-cost materials for each; the evaporation medium may be a cellulose pad, porous ceramic, etc., and may be configured as a replaceable cassette. The second fluid that has not evaporated is recovered from a water reservoir and recirculated. If necessary, the lower limit of evaporative cooling can be supplemented by an auxiliary cooling element made of a thermoelectric element, a magneto-thermal element, or an elastic-thermal shape memory alloy. The circulating water in contact with the user is isolated from the outside air for hygiene, operates with low power consumption without a compressor or active refrigeration element, and the control unit actively variably controls the fluid transfer means according to temperature and humidity.

Description

Technology Field

[0001] The present invention relates to a cooling mat system for sleeping and indoor / outdoor activities, and more specifically, to a cold water mat system and a control method thereof, which has a structure in which circulating water inside the mat that has absorbed the user's body heat is transferred to a heat dissipation unit via a heat pipe and released to the outside, and in which the heat dissipation of the heat dissipation unit can be reinforced by evaporative cooling as needed, and which actively variably controls a fluid transfer means according to ambient temperature and humidity. Background Technology

[0003] Conventional water-cooled cooling mats are broadly classified into methods that circulate ice water, methods using Peltier (thermoelectric elements), and methods using compressors.

[0004] The ice water circulation method involves the inconvenience of having to periodically replace the ice. The Peltier method suffers from low thermodynamic efficiency due to the low coefficient of performance of its thermoelectric elements, requires high power consumption for significant cooling, and generates significant noise from the cooling fans used for heat dissipation on the high-temperature side. The compressor method is bulky, involves vibration and noise, and has a high manufacturing cost.

[0005] Meanwhile, although a direct evaporative cooling mat utilizing the latent heat of water evaporation has been proposed, hygiene problems arise as the water circulating through the mat becomes contaminated through continuous contact with the outside air, leading to the proliferation of scale and mold inside the mat.

[0006] The present invention is based on the fundamental principle of transferring and releasing the user's body heat through a heat pipe to a heat dissipation unit. In this case, when the heat dissipation unit is cooled by air convection alone, the temperature of the heat dissipation unit is lowered only to the dry-bulb temperature of the outside air, so there is a limit to the cooling performance in environments where the outside air temperature is high. On the other hand, when the heat dissipation of the heat dissipation unit is reinforced by the latent heat of evaporation of evaporated water physically separated from the circulating water, the temperature of the heat dissipation unit can be lowered to the wet-bulb temperature, which is lower than the dry-bulb temperature, making it possible to achieve cooling lower than the outside air temperature.

[0007] However, since the aforementioned reinforcement via evaporation entails additional components to enhance evaporation performance, a structure is required that allows for the selection of a heat dissipation method or the addition of reinforcement configurations depending on the usage environment. Furthermore, hygienic management of the evaporation surface, a continuous supply of evaporated water, and active response to changes in ambient humidity are necessary. The problem to be solved

[0009] The present invention has been devised to solve the problems of the prior art as described above, and

[0010] First, the purpose is to provide a basic structure that transfers and releases the user's body heat to a heat dissipation unit through a heat pipe, while also providing a hygienic cooling structure that prevents contamination inside the mat by isolating the circulating water the user comes into contact with from external air and contaminants.

[0011] Second, the purpose is to provide a structure capable of cooling the mat to a temperature lower than the external air temperature by reinforcing the heat dissipation of the above-mentioned heat dissipation part with the latent heat of evaporation of evaporated water physically separated from the above-mentioned circulating water.

[0012] Third, the purpose is to configure the heat transfer in the heat dissipation section and the evaporation in the evaporation surface to be shared by different components, thereby enabling each component to be composed of low-cost materials optimized for its function.

[0013] Fourth, the purpose is to provide a cooling system that maintains the evaporation surface hygienically, continuously supplies evaporated water, and operates with low power consumption by using a fluid transfer means as the main driving load without active refrigeration elements with a low coefficient of performance or bulky compressors.

[0014] Fifth, the purpose is to provide a control method that actively and variably controls the drive of a fluid transfer means according to ambient temperature and humidity, thereby balancing cooling performance and drive noise under various environmental conditions. means of solving the problem

[0016] The cold water mat system of the present invention for achieving the above objective is,

[0017] A user mat with a channel formed therein through which a first fluid circulates;

[0018] A water pump that forms a closed loop with the above mat to forcibly circulate the first fluid;

[0019] A water block disposed on the above closed loop through which the first fluid passes;

[0020] One or more heat pipes, wherein a heating portion at one end is thermally coupled to the water block to absorb heat from the first fluid, and a heat dissipation portion at the other end releases the heat to the outside;

[0021] A heat dissipation member that is thermally coupled to the heat dissipation portion of the heat pipe to expand the surface area; and

[0022] It is characterized by including a control unit that controls the operation of the above water pump.

[0023] A cold water mat system according to one embodiment of the present invention, in order to reinforce the heat dissipation of the heat dissipation part with latent heat of evaporation,

[0024] An evaporation medium that absorbs and evaporates a second fluid physically separated from the first fluid;

[0025] A sacrificial water supply unit that supplies the second fluid to the above evaporation medium; and

[0026] It further includes an exhaust fan that blows external air toward the evaporation medium to accelerate the evaporation of the second fluid,

[0027] The above evaporation medium is positioned adjacent to the heat dissipation member and is characterized by cooling the heat dissipation member and the heat dissipation portion of the heat pipe with the latent heat of evaporation of the second fluid.

[0028] Here, the control unit further includes a temperature and humidity sensor that measures ambient temperature and humidity, and can variably control the operation of the water pump and the exhaust fan according to the measured temperature and humidity. Effects of the invention

[0030] According to the present invention, the following effects are achieved.

[0031] First, the user's body heat is transferred to the heat dissipation section through the heat pipe and released, and since the circulating water (first fluid) in contact with the user is isolated from external air and contaminants within a closed loop, hygiene can be ensured so that mold or water stains do not occur inside the mat.

[0032] Second, when the heat dissipation of the heat dissipation part is reinforced with latent heat of evaporation, the temperature of the heat dissipation part and the circulating water can be lowered to a wet-bulb temperature lower than the dry-bulb temperature of the outside air, allowing the mat to be cooled to a temperature lower than the outside air temperature. On the other hand, even without adding an evaporation reinforcement configuration, a cooling effect can be obtained by releasing the user's body heat to the outside using only the heat pipe and the heat dissipation member, so the configuration can be selected according to the usage environment.

[0033] Third, since the heat dissipation component responsible for heat transfer in the heat dissipation section and the evaporation medium responsible for evaporation are composed of different materials, the heat dissipation component can be configured with a material having excellent thermal conductivity, and the evaporation medium can be configured with a low-cost material having excellent absorption and evaporation properties, each optimized for their respective functions, and the heat dissipation component does not require separate hydrophilic treatment.

[0034] Fourth, when the second fluid that has not been evaporated is recovered and recirculated, the entire evaporation surface is uniformly wetted, thereby suppressing performance degradation and reducing the consumption of the second fluid, and if the evaporation medium is configured to be replaceable, hygiene management is easy.

[0035] Fifth, since the fluid transfer means is the main driving load without active refrigeration elements with a low coefficient of performance or bulky compressors, it can be driven with lower power consumption compared to the method using active refrigeration elements based on an equivalent cooling effect.

[0036] Sixth, since the control unit actively regulates the operation of the fluid transfer means based on the temperature and humidity sensor, it is possible to maintain a balance between cooling performance and driving noise under various environmental conditions. Brief explanation of the drawing

[0038] FIG. 1 is an overall mechanical block diagram of a cold water mat system according to one embodiment of the present invention. FIG. 2 is a conceptual cross-sectional diagram showing a heat dissipation member, an evaporation medium, and a sacrificial water recirculation structure according to one embodiment of the present invention. FIG. 3 is a flowchart showing the temperature and humidity-based variable control logic of a control unit according to one embodiment of the present invention. Specific details for implementing the invention

[0039] The following description is intended to illustratively explain the principles and configurations of the present invention and does not limit the scope of the present invention to specific materials, parts, numerical values, or arrangements. A person skilled in the art to which the present invention pertains may implement various modifications and equivalents within the scope of the principles described below.

[0040] The basic principle of the present invention is to transfer the heat of a first fluid, which has absorbed the user's body heat, to a heat dissipation member via a heat pipe and release it to the outside.

[0041] At this time

[0042] a. The point that the first fluid contacted by the user is isolated from the outside within a closed loop,

[0043] b. The heat dissipation of the heat dissipation part is selectively reinforced by the latent heat of evaporation of the second fluid separated from the first fluid to achieve cooling lower than the external air temperature.

[0044] c. The fact that the heat dissipation component responsible for heat transfer and the evaporation medium responsible for evaporation are separated by function and optimized separately at low cost, and (

[0045] D. The variable control of the fluid transfer means according to ambient temperature and humidity constitutes the core principle of the present invention.

[0047] Basic heat dissipation structure

[0048] A flow path is formed inside the mat (100) through which a first fluid (W1) circulates, and the first fluid (W1) circulates between the mat (100) and the water block (120) by a water pump (110), absorbing the user's body heat and transferring it to the water block.

[0049] One or more heating portions (131) of a heat pipe (130) are thermally coupled to the water block (120). The heating portions of the heat pipes may be embedded inside the water block or bonded to its surface to reduce thermal contact resistance with the first fluid. A heat dissipation member (140) that expands the surface area is thermally coupled to the heat dissipation portion (132) of the heat pipe (130).

[0050] The heat dissipation member is formed of a thermally conductive material and may include a plurality of heat dissipation fins, a heat diffusion sheet, or a combination thereof. The heat dissipation member may be formed of a metal such as aluminum, and as another embodiment, may include a carbon fiber composite material with high planar thermal conductivity to ensure lightweightness and corrosion resistance.

[0051] Even when the user's body heat is released to the outside air solely by the heat dissipation member, the heat pipe transfers heat without consuming power, thereby providing hygienic and quiet cooling. However, in this case, since the temperature of the heat dissipation member is lowered to the dry-bulb temperature of the outside air, if cooling lower than the outside air temperature is required, the evaporation reinforcement configuration described below is added.

[0053] Evaporation reinforcement structure and functional separation

[0054] In order to reinforce the heat dissipation of the heat dissipation section with latent heat of evaporation, an evaporation medium (210) is disposed adjacent to the heat dissipation member (140). The evaporation medium contains a second fluid (sacrificial water) that is physically separated from the first fluid, and as external air blown by an exhaust fan passes through the evaporation medium, it evaporates the second fluid, and the latent heat of evaporation cools the heat dissipation section of the heat pipe through the heat dissipation member.

[0055] In the present invention, the heat dissipation member responsible for heat transfer and the evaporation medium responsible for evaporation are configured as separate members. Accordingly, the heat dissipation member can be optimized to a material with excellent thermal conductivity, and the evaporation medium can be optimized to a material with excellent absorbency and evaporability, and a separate hydrophilic treatment is not required on the surface of the heat dissipation member.

[0056] As the evaporation medium, an absorbent porous material that draws up water by capillary force and provides a large evaporation surface area may be used. In one embodiment, the evaporation medium may include one or more of corrugated laminated cellulose pads, porous ceramics, porous foams, nonwoven fabrics, or hygroscopic fibers. The cellulose pads provide high absorption capacity and an evaporation surface area at a low cost, and the porous ceramics, being inorganic, are resistant to mold and corrosion, allowing for semi-permanent use. The evaporation medium may be treated with an antimicrobial agent to inhibit microbial growth, and the evaporation medium may be configured in a replaceable cassette form to facilitate hygienic maintenance.

[0058] Supply and Recirculation of Sacrificial Water

[0059] The sacrificial water supply unit (220) may, in one embodiment, include a spray unit (221) that wets the evaporation medium by flowing a second fluid (W2) from the upper part of the evaporation medium (210), a reservoir unit (222) that collects the second fluid that falls to the lower part without evaporating, and a circulation pump (223) that recirculates the second fluid from the reservoir unit to the spray unit. Accordingly, the entire evaporation medium is continuously and uniformly wetted, and since only the amount consumed by evaporation needs to be replenished, the consumption of the second fluid is reduced.

[0060] A water level sensor for detecting the remaining amount of the second fluid may be placed in the above-mentioned reservoir, and the reservoir may be configured in the form of a water container detachable from the main body to reduce the volume of the system and facilitate replenishment.

[0062] Auxiliary cooling element (other examples)

[0063] As another embodiment, to compensate for the fact that the lower limit of cooling by evaporation is limited by the wet-bulb temperature, an auxiliary cooling element may be further placed in the closed loop or the heat dissipation part. The auxiliary cooling element is configured to share only the temperature difference from the temperature cooled by evaporation to the target temperature, thereby reducing the load and power consumption.

[0064] A thermoelectric element (Peltier element) may be used as the auxiliary cooling element (250). In another embodiment, the auxiliary cooling element may include a solid cooling element whose temperature changes according to changes in the applied magnetic field or mechanical stress, such as a magnetic material having a magnetothermal effect or a shape memory alloy having an elastic thermoothermal effect, in which case the circulating water or heat dissipation part can be cooled without using a refrigerant.

[0066] Operation of the control unit

[0067] The operation of the above control unit (300, MCU) is explained with reference to the flowchart of FIG. 3. When control is initiated (S100), the control unit measures the ambient temperature and humidity from the temperature and humidity sensor (310) (S110), and calculates the dew point and wet-bulb temperature based on the measured data (S120).

[0068] Next, the control unit compares the measured humidity with a preset first threshold (S130). If the measured humidity is determined to be in a high humidity state exceeding the first threshold, natural evaporation is suppressed, so the control unit performs a high humidity mode to increase the Pulse Width Modulation (PWM) duty ratio of the exhaust fan (230) to increase the amount of air passing through the evaporation medium (210) and increase forced vaporization (S140).

[0069] If the measured humidity is below the first threshold, the control unit compares the measured humidity with a preset second threshold (S150). If the measured humidity is below the second threshold and is in a dry state, the control unit performs a drying mode to reduce driving noise by lowering the PWM duty ratio of the exhaust fan and balances cooling responsiveness and power consumption by adjusting the PWM duty ratio of the water pump (110) (S160). If the measured humidity is above the second threshold, the control unit performs a standard mode that maintains the current PWM setting (S170).

[0070] In each of the above modes, the control unit independently variably controls the PWM duty ratios of the water pump and the exhaust fan with respect to the measured humidity (S180). The control unit periodically repeats the measurement and control process described above.

[0071] The system of the present invention can be powered by a commercial power source, a portable power source, or a combination thereof, and since a driving means for transporting fluid instead of an active refrigeration element is used as the main driving load, it can be operated with lower power consumption compared to a method using an active refrigeration element based on an equivalent amount of cooling.

[0073] Dehumidification cartridge (optional example)

[0074] In another embodiment, a removable dehumidifying cartridge (240) containing a hygroscopic medium may be further disposed in the path through which external air flows into the evaporation medium. When the incoming air passes through the dehumidifying cartridge, the absolute humidity is reduced, increasing the evaporation rate per unit time in the evaporation medium, and suppressing the rise in indoor humidity due to evaporation and condensation around the mat. The dehumidifying cartridge is detached by the user, regenerated by an external heat source or natural drying, and then reinstalled for reuse. Explanation of the symbols

[0076] 100: User Mat 110: Water pump 120: Water Block 130: Heat pipe 131: Heating part 132: Heat dissipation section 140: Heat dissipation component 200: Evaporation system 210: Evaporative medium 220: Sacrifice Supply Unit 221: Spearman 222: Reservoir 223: Circulation pump 230: Exhaust fan 240: Dehumidifying cartridge 250: Auxiliary cooling element 300: Control Unit (MCU) 310: Temperature and humidity sensor W1: First fluid (circulating water) W2: Second fluid (sacrificial water)

Claims

Claim 1 A cold water mat system comprising: a mat having a flow path formed therein through which a first fluid circulates; a water pump that circulates the first fluid in a closed loop; a water block through which the first fluid passes and transfers heat; one or more heat pipes, one end of which is thermally coupled to the water block and the other end of which forms a heat dissipation section; a heat dissipation member that is thermally coupled to the heat dissipation section of the heat pipe to expand the surface area; and a control unit that controls the operation of the water pump, wherein the heat of the first fluid that has absorbed the body heat of a user is transferred to the heat dissipation member through the heat pipe and released to the outside. Claim 2 A cold water mat system according to claim 1, further comprising: an evaporation medium that absorbs and evaporates a second fluid physically separated from the first fluid; a sacrificial water supply unit that supplies the second fluid to the evaporation medium; and an exhaust fan that blows external air toward the evaporation medium to accelerate the evaporation of the second fluid, wherein the evaporation medium is positioned adjacent to the heat dissipation member to cool the heat dissipation member and the heat dissipation part of the heat pipe with the latent heat of evaporation of the second fluid, wherein the heat dissipation member is configured to be separated into different members so as to be responsible for heat transfer and the evaporation medium is responsible for evaporation, and wherein the first fluid and the second fluid only exchange heat with each other through the wall of the heat pipe and are not physically mixed. Claim 3 A cold water mat system according to paragraph 2, wherein the evaporation medium comprises one or more of corrugated laminated cellulose pads, porous ceramics, porous foams, nonwoven fabrics, and hygroscopic fibers, and is configured in a replaceable cassette form. Claim 4 A cold water mat system according to paragraph 2, wherein the sacrificial water supply unit comprises: a spray unit that wets the evaporation medium by flowing the second fluid from the upper part of the evaporation medium; a reservoir unit that collects the second fluid that falls without evaporating from the evaporation medium; and a circulation pump that recirculates the second fluid from the reservoir unit to the spray unit. Claim 5 A cold water mat system according to claim 2, further comprising an auxiliary cooling element disposed in the closed loop or the heat dissipation part to share the temperature difference from the temperature cooled by evaporation to the target temperature, wherein the auxiliary cooling element comprises one or more of a thermoelectric element, a magnetic material having a magnetothermal effect, and a shape memory alloy having an elastic thermoothermal effect. Claim 6 A cold water mat system according to paragraph 2, wherein the control unit further includes a temperature and humidity sensor for measuring ambient temperature and humidity, and when the measured humidity exceeds a preset threshold, increases the Pulse Width Modulation (PWM) duty ratio of the exhaust fan to increase the amount of air passing through the evaporation medium, and independently variably controls the PWM duty ratio of the water pump and the PWM duty ratio of the exhaust fan with respect to the measured humidity. Claim 7 A method for cooling a cold water mat in which a first fluid circulates, comprising: a step in which a water pump circulates the first fluid in a closed loop between the mat and a water block to transfer heat from a user to the water block; a step in which a heat pipe transfers heat from the water block to a heat dissipation member coupled to a heat dissipation part of the heat pipe and releases it to the outside; and a step in which a control unit controls the operation of the water pump. Claim 8 A method for cooling a cold water mat according to claim 7, further comprising the steps of: supplying a second fluid, which is physically separated from the first fluid, to an evaporation medium adjacent to the heat dissipation member to wet it; and blowing external air into the evaporation medium to evaporate the second fluid, and cooling the heat dissipation portion of the heat dissipation member and the heat pipe with the latent heat of evaporation.

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