Heat pipe heat collector with heat storage device

Abstract

The utility model discloses a heat pipe heat collector with a heat storage device, which comprises a double-layer vacuum glass pipe, a heat conduction piece is connected in the double-layer vacuum glass pipe, and the heat conduction piece is connected with a heat pipe; the heat conduction piece comprises heat conduction fins which are tile-shaped, and the outer sides of the heat conduction fins are tightly attached to the inner layer of the double-layer vacuum glass tube. The heat conduction piece further comprises an inner heat conduction part, the inner heat conduction part is formed by cutting a long straight through notch between the two ends of a cylinder, and the inner surface of the inner heat conduction part is tightly connected with the heat pipe in a sleeved mode. The heat conduction piece is in heat conduction connection with a metal pipe, and a phase change heat storage capsule is arranged in the metal pipe. The scheme has the beneficial effects that according to the description of the scheme, the structure is simple, the design is reasonable, the temperature of a medium in the heat pipe collector can be effectively limited, and the safety problem of overhigh pressure caused by overhigh temperature of a hot water system is avoided; and meanwhile, the working time of the heat pipe heat collector is prolonged, so that the capacity of the corresponding heat storage unit can be reduced, and the investment of the heat storage unit is saved.

Description

Technical Field

[0001] The utility model relates to the field of solar collectors, in particular to a heat pipe collector with a heat storage device. Background Art

[0002] At present, the commonly used solar heat pipe heat collection devices in China mainly include three types: all-glass vacuum heat pipes, glass tube-U-shaped tubes, and glass tube-metal heat pipes. A glass tube-metal heat pipe collector generally consists of a double-layer glass vacuum tube, an absorption coating, heat conduction fins (aluminum wings), a heat pipe, a heat conduction block, a header pipe, a heat preservation box, a sealing ring, etc. Its basic working principle is as follows: sunlight passes through the vacuum glass tube and irradiates on the selective absorption film on the inner tube of the vacuum glass tube. The film layer converts solar energy into heat energy. The heat energy is transmitted to the built-in heat pipe through the aluminum wings, quickly heating and vaporizing the working medium in the evaporation end of the heat pipe. The vaporized working medium rises to the condensation end of the heat pipe, causing the condensation end to quickly heat up, and conducting and collecting the energy to the medium (such as water, ethylene glycol, etc.) in the header pipe through the heat conduction block. After the heat pipe working medium releases the latent heat of vaporization, it condenses into a liquid, flows back to the evaporation end of the heat pipe under the action of gravity, absorbs heat, vaporizes and rises again, and condenses and flows back again, working in a cycle. The heat pipe type collector continuously absorbs solar radiation energy through the vapor-liquid phase change cycle process of the working medium in the heat pipe to provide heat energy for the system. The heat collected by the header pipe is generally connected to a heat storage unit (hot water storage tank) through a circulation pipeline, and the heat is stored in the heat storage unit through direct or indirect heat exchange. By heating the working medium in the heat pipe with solar energy, the working medium in the heat pipe transfers the heat to the working medium in the header pipe through the vapor-liquid phase change cycle process. The working medium in the header pipe transfers the heat to the heat storage unit through the circulation pipeline. During normal operation, the working medium in the heat storage unit consumes the heat through circulation every day (for example, users take hot water for bathing). The heat storage unit will maintain within an appropriate temperature range (60-70°C). The working medium in the header pipe will absorb the heat of the heat pipe unit and transfer it to the heat storage unit through the circulation pipeline. The temperature of the heat pipe unit will not exceed 80-100°C. However, when users go out for a long time and do not use the hot water in the heat storage unit for a long time, it will cause the temperature difference between the working medium in the heat storage unit and the working medium in the header pipe to become smaller. When the solar radiation is sufficient in summer, it is easy to cause the temperature of the heat pipe unit to exceed 110°C, and at the same time cause the temperature of the working medium in the header pipe to exceed 90°C, thereby causing the temperature of the working medium in the heat storage unit to exceed 90°C. This will lead to an increase in the pressure of the entire system, a reduction in safety performance, and a reduction in heat exchange efficiency.

[0003] At the same time, due to the periodicity of solar radiation, the heat pipe collector generally stops heat collection work at dusk (6-7 pm). This requires a reasonable heat storage unit to store the heat energy collected by the collector during the day for use at night. Increasing the working time of the collector can correspondingly reduce the storage capacity of the heat storage unit.

[0004] CN212566340U proposes a heat collecting pipe unit and a heat collecting and temperature controlling phase change capacity increasing solar water heating system. A closed heat collecting capacity cavity is arranged inside the heat collecting pipe body, and a gas-liquid phase change material is filled in the heat collecting capacity cavity. The phase change temperature of the gas-liquid phase change material is 80 - 85 °C. After the heat collecting pipe body absorbs heat, it heats the temperature of the gas-liquid phase change material. Initially, the enterprise phase change material is in a liquid state and absorbs heat in the form of sensible heat. When the temperature of the gas-liquid phase change material reaches the phase change temperature, the heat absorption method changes from sensible heat to latent heat, so as to keep the temperature of the heat collecting pipe body unchanged. The medium in the combined collector inner cavity absorbs a large amount of heat after passing through the heat collecting pipe body, causing the temperature of the gas-liquid phase change material to drop rapidly and re-enter the liquid sensible heat absorption state; since the phase change temperature of the gas-liquid phase change material is 80 - 85 °C, the temperature of the medium will not exceed 90 °C, which can effectively limit the temperature of the medium in the heat pipe collector and avoid safety problems caused by too high temperature of the hot water system; at the same time, a plurality of phase change heat storage balls are placed in the hot water storage tank. When the temperature in the hot water storage tank reaches the phase change temperature (50 - 55 °C) of the phase change heat storage balls, the solid-liquid phase change material in the phase change heat storage balls undergoes a solid-liquid phase change. The solid-liquid phase change material absorbs a large amount of heat and keeps the temperature unchanged, causing the temperature of the hot water storage tank to rise to a certain range (below 80 °C) and remain relatively stable. The cooperation of the two phase change materials realizes the effects of a large amount of heat storage and temperature control. However, when the solar irradiation intensity is relatively high in summer and it is not used for a long time, this method will still cause the temperature of the heat pipe unit to be too high (higher than 100 °C), and adding a large number of phase change heat storage balls in the hot water storage tank increases the complexity and maintenance cost of the system. There is also a method proposed to fill the glass tube with heat-conducting oil instead of aluminum wings, which can improve the heat transfer efficiency, prevent overheating, and has a certain heat storage function. However, directly adding heat-conducting oil in the glass tube puts higher requirements on the sealing of the glass tube and the combined collector tube, and at the same time is more likely to burst the tube. When the glass tube bursts, the maintenance is complex and the cost increases. Summary of the Utility Model

[0005] The utility model aims at the deficiencies existing in the prior art, and provides a heat pipe collector with a heat storage device, which has a simple structure and reasonable design, enables the temperature of the working medium in the combined collector tube not to exceed 90 °C, can effectively limit the temperature of the medium in the heat pipe collector, and avoid safety problems of excessive pressure caused by too high temperature of the hot water system; at the same time, when the solar irradiation is insufficient, it releases the stored heat, extends the working time of the heat pipe collector, and thus can reduce the capacity of the corresponding heat storage unit and save the investment in the heat storage unit.

[0006] To achieve the above object, the utility model provides a heat pipe collector with a heat storage device, including a double-layer vacuum glass tube, the outer layer of the double-layer vacuum glass tube is a transparent glass layer, and the inner layer surface is coated with a selective absorption coating;

[0007] Inside the double-layer vacuum glass tube, there is a heat conducting member connected thereto. The heat conducting member is connected to a heat pipe. The heat pipe includes a condensation section, an adiabatic section, and an evaporation section. The evaporation section is located at the axial center position of the double-layer vacuum glass tube;

[0008] The heat conducting member includes heat conducting fins. The heat conducting fins are in the shape of tiles. The outer side of the heat conducting fins is closely attached to the inner layer of the double-layer vacuum glass tube;

[0009] The heat conducting member further includes an inner heat conducting part. The shape of the inner heat conducting part is like a long straight through notch being cut off between the two ends of a cylinder. The inner surface of the inner heat conducting part is closely attached to and sleeved on the heat pipe;

[0010] The heat conducting member is thermally conductively connected to a metal tube. A phase change heat storage capsule is arranged inside the metal tube.

[0011] Further, the heat conducting fins are connected to a first connecting piece. The first connecting piece is connected to a middle heat conducting tile. The middle heat conducting tile is connected to a second connecting piece. The second connecting piece is connected to the inner heat conducting part;

[0012] The included angle at the connection between the heat conducting fins and the first connecting piece is an acute angle;

[0013] The included angle at the connection between the first connecting piece and the outer side of the middle heat conducting tile is an acute angle;

[0014] The included angle at the connection between the second connecting piece and the outer side of the middle heat conducting tile is an obtuse angle;

[0015] The included angle at the connection between the second connecting piece and the outer side of the inner heat conducting part is an acute angle;

[0016] When the metal tube is connected to the heat conducting member, the inner side of the middle heat conducting tile is closely attached to the metal tube.

[0017] Further, the heat conducting member includes two heat conducting fins. Between the two heat conducting fins and the inner heat conducting part, there is one first connecting piece, one middle heat conducting tile, and one second connecting piece respectively connected thereto.

[0018] Further, the diameter of the metal tube is larger than the diameter of the heat pipe. The material of the metal tube is steel, aluminum, or stainless steel.

[0019] Further, the length of the metal tube is less than or equal to the length of the heat conducting fins.

[0020] Further, the phase change temperature of the phase change heat storage capsule is 60 - 80 °C.

[0021] Further, the phase change heat storage capsule occupies 60 - 80% of the volume of the metal tube.

[0022] Further, the heat-conducting fins are connected with a first telescopic member, the first telescopic member includes a first inner cylinder, the first inner cylinder is slidably sleeved with a first outer cylinder, and the first outer cylinder is connected with the metal tube;

[0023] A first elastic package is arranged between the first inner cylinder and the first outer cylinder, a first gas-liquid phase change material is arranged in the inner cavity of the first elastic package, and the evaporation temperature of the first gas-liquid phase change material is greater than a first set temperature;

[0024] The outer wall of the metal tube is connected with a second telescopic member at the position inside the inner cavity of the first outer cylinder, the second telescopic member includes a second outer cylinder, and the second outer cylinder is slidably sleeved with a second inner cylinder;

[0025] A second elastic package is arranged between the second inner cylinder and the second outer cylinder, a second gas-liquid phase change material is arranged in the inner cavity of the second elastic package, and the evaporation temperature of the second gas-liquid phase change material is greater than a second set temperature;

[0026] When the first telescopic member extends and the second telescopic member also extends, the second inner cylinder will abut against the end of the first inner cylinder, thereby preventing the first telescopic member from contracting;

[0027] A tension spring is connected between the metal tube and the heat-conducting fins near the connection of the first telescopic member.

[0028] When the work starts, the first telescopic member and the second telescopic member are also in a contracted state. At this time, the metal tube is separated from the heat-conducting member.

[0029] When the double-layer vacuum glass tube is irradiated by the sun, the double-layer vacuum glass tube absorbs heat and conducts it to the heat-conducting member, and the heat-conducting member conducts the heat to the evaporation section of the heat pipe.

[0030] If no one uses the heat, the temperature of the heat pipe will continue to rise. When the relative temperature between the heat pipe and the double-layer vacuum glass tube decreases, the speed of the double-layer vacuum glass tube releasing heat through heat conduction will be reduced, and thus the temperature will continue to rise.

[0031] In this way, the metal tube can not only absorb heat to prevent the temperature of the heat pipe from being too high, but also will not compete with the heat pipe for heat when the heat pipe is in use, resulting in too slow a rise in the temperature of the heat pipe.

[0032] When the double-layer vacuum glass tube is greater than the first set temperature, the first gas-liquid phase change material in the first elastic package starts to evaporate, and the first telescopic member overcomes the pulling force of the tension spring and presses the metal tube against the surface of the middle heat-conducting tile.

[0033] After the middle heat-conducting tile heats the metal tube, the metal tube heats the second telescopic member, and the second telescopic member extends the second inner cylinder to clamp the first inner cylinder.

[0034] When night falls, the first telescopic member loses pressure. Since the temperature of the metal tube is still high and the second inner cylinder does not contract, the first telescopic member will not contract.

[0035] Only when the temperature of the metal tube also drops and the second telescopic member also contracts, under the pulling force of the tension spring, will the first telescopic member contract.

[0036] In this way, after night falls, the heat stored in the metal tube can be effectively utilized.

[0037] The beneficial effects of this solution can be known from the description of the above solution. The structure is simple and the design is reasonable, with the following advantages:

[0038] (1) When there is a risk of the heat pipe temperature being too high, the solar heat is conducted to the phase change heat storage capsule in the metal tube. The initial state of the phase change heat storage capsule is solid, and it absorbs heat in the form of sensible heat. When the temperature of the phase change heat storage capsule reaches the phase change temperature, the heat absorption method changes from sensible heat to latent heat, and the temperature of the heat pipe unit is maintained constant. Since the phase change temperature of the phase change heat storage capsule is 60 - 80°C, the temperature of the working medium in the header will not exceed 90°C, which can effectively limit the temperature of the medium in the heat pipe collector and avoid the safety problem of excessive pressure caused by too high a temperature in the hot water system;

[0039] (2) At the same time, when the solar irradiation is insufficient, such as after the sun goes down, the phase change heat storage capsule installed in the metal tube can release the stored heat, extend the working time of the heat pipe collector, reduce the capacity of the corresponding heat storage unit, and save the investment in the heat storage unit;

[0040] (3) The first telescopic member is provided to prevent the metal tube from contacting the heat conducting member in the normal state and robbing the heat energy of the heat pipe, which reduces the heating efficiency of the heat pipe;

[0041] (4) The second telescopic member is provided to prevent the heat of the metal tube from not being effectively utilized;

[0042] (5) The included angle between the outer connection of the second connecting piece and the middle heat conducting tile is an obtuse angle to avoid interference during the movement of the metal tube; the included angle between the heat conducting fin and the first connecting piece is an acute angle, the included angle between the first connecting piece and the outer connection of the middle heat conducting tile is an acute angle, and the included angle between the second connecting piece and the outer connection of the inner heat conducting part is an acute angle. This is to facilitate deformation during thermal expansion and contraction and prevent excessive force from being transmitted to the double - layer vacuum glass tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a schematic structural diagram of the present utility model;

[0044] Figure 2 is Figure 1 an enlarged view of part I;

[0045] Figure 3 is Figure 1 the A-A cross-sectional view of;

[0046] Figure 4 is the structural schematic diagram of the heat conducting member of the present utility model;

[0047] In the figure, 1. double-layer vacuum glass tube; 2. heat conducting member; 3. heat pipe; 4. heat conducting fin; 5. inner heat conducting part; 6. metal tube; 7. first connecting piece; 8. middle heat conducting tile; 9. first inner cylinder; 10. first outer cylinder; 11. second outer cylinder; 12. second inner cylinder; 13. tension spring; 14. second connecting piece. Specific embodiments

[0048] To clearly illustrate the technical features of this solution, the following elaborates on this solution through specific embodiments.

[0049] As Figures 1-4 shown, this embodiment is a heat pipe 3 collector with a heat storage device, including a double-layer vacuum glass tube 1. The outer layer of the double-layer vacuum glass tube 1 is a transparent glass layer, and the inner layer surface is coated with a selective absorption coating;

[0050] Inside the double-layer vacuum glass tube 1 is connected with a heat conducting member 2, and the heat conducting member 2 is connected with a heat pipe 3. The heat pipe 3 includes a condensation section, an adiabatic section, and an evaporation section, and the evaporation section is located at the axis position of the double-layer vacuum glass tube 1;

[0051] The heat conducting member 2 includes heat conducting fins 4. The heat conducting fins 4 are in a tile shape, and the outer side of the heat conducting fins 4 is closely attached to the inner layer of the double-layer vacuum glass tube 1;

[0052] The heat conducting member 2 further includes an inner heat conducting part 5. The shape of the inner heat conducting part 5 is like a cylindrical shape with a long straight through notch cut between two ends. The inner surface of the inner heat conducting part 5 is closely attached and sleeved on the heat pipe 3;

[0053] The heat conducting member 2 is thermally conduction-connected to a metal tube 6, and a phase change heat storage capsule is arranged inside the metal tube 6.

[0054] Furthermore, the heat conducting fin 4 is connected with a first connecting piece 7, the first connecting piece 7 is connected with a middle heat conducting tile 8, the middle heat conducting tile 8 is connected with a second connecting piece 14, and the second connecting piece 14 is connected with the inner heat conducting part 5;

[0055] The included angle at the connection between the heat conducting fin 4 and the first connecting piece 7 is an acute angle;

[0056] The included angle at the outer connection between the first connecting piece 7 and the middle heat conducting tile 8 is an acute angle;

[0057] The included angle at the outer connection between the second connecting piece 14 and the middle heat conducting tile 8 is an obtuse angle;

[0058] The included angle at the outer connection between the second connecting piece 14 and the inner heat conducting part 5 is an acute angle;

[0059] When the metal tube 6 is connected to the heat conducting member 2, the inner side of the middle heat conducting tile 8 is closely attached to the metal tube 6.

[0060] Furthermore, the heat conducting member 2 includes two heat conducting fins 4, and a first connecting piece 7, a middle heat conducting tile 8 and a second connecting piece 14 are connected between the two heat conducting fins 4 and the inner heat conducting part 5.

[0061] Furthermore, the diameter of the metal tube 6 is larger than the diameter of the heat pipe 3, and the material of the metal tube 6 is steel, aluminum or stainless steel.

[0062] Furthermore, the length of the metal tube 6 is less than or equal to the length of the heat conducting fin 4.

[0063] Furthermore, the phase change temperature of the phase change heat storage capsule is 60 - 80 °C.

[0064] Furthermore, the phase change heat storage capsule occupies 60 - 80% of the volume of the metal tube 6.

[0065] Furthermore, the heat conducting fin 4 is connected with a first telescopic member. The first telescopic member includes a first inner cylinder 9, the first inner cylinder 9 is slidably sleeved with a first outer cylinder 10, and the first outer cylinder 10 is connected with the metal tube 6;

[0066] A first elastic package is arranged between the first inner cylinder 9 and the first outer cylinder 10, and a first gas - liquid phase change material is arranged in the inner cavity of the first elastic package. The evaporation temperature of the first gas - liquid phase change material is greater than the first set temperature;

[0067] On the outer wall of the metal tube 6 at the position inside the inner cavity of the first outer cylinder 10, a second telescopic member is connected. The second telescopic member includes a second outer cylinder 11, and the second outer cylinder 11 is slidably sleeved with a second inner cylinder 12;

[0068] A second elastic package is arranged between the second inner cylinder 12 and the second outer cylinder 11, and a second gas - liquid phase change material is arranged in the inner cavity of the second elastic package. The evaporation temperature of the second gas - liquid phase change material is greater than the second set temperature;

[0069] When the first telescopic member extends and the second telescopic member also extends, the second inner cylinder 12 will abut against the end of the first inner cylinder 9, thereby preventing the first telescopic member from contracting;

[0070] A tension spring 13 is connected between the metal tube 6 and the heat conducting fin 4 near the first telescopic member.

[0071] When the work starts, the first telescopic member and the second telescopic member are also in a contracted state. At this time, the metal tube 6 is in a separated state from the heat conducting member 2.

[0072] When the double - layer vacuum glass tube 1 is irradiated by the sun, the double - layer vacuum glass tube 1 absorbs heat and conducts it to the heat conducting member 2, and the heat conducting member 2 conducts the heat to the evaporation section of the heat pipe 3.

[0073] If no one uses the heat, the temperature of the heat pipe 3 will continue to rise. When the relative temperature between the heat pipe 3 and the double-layer vacuum glass tube 1 decreases, the speed at which the double-layer vacuum glass tube 1 releases heat through heat conduction will be reduced, and thus the temperature will continue to rise.

[0074] In this way, the metal tube 6 can not only absorb heat to prevent the temperature of the heat pipe 3 from being too high, but also will not compete with the heat pipe 3 for heat when the heat pipe 3 is in use, resulting in the heat pipe 3 heating up too slowly.

[0075] When the double-layer vacuum glass tube 1 is greater than the first set temperature, the first gas-liquid phase change material in the first elastic package starts to evaporate, and the first telescopic member overcomes the pulling force of the tension spring 13 to squeeze the metal tube 6 onto the surface of the middle heat conducting tile 8.

[0076] After the middle heat conducting tile 8 heats the metal tube 6, the metal tube 6 heats the second telescopic member, and the second telescopic member extends out of the second inner cylinder 12 to catch the first inner cylinder 9.

[0077] When night falls, the first telescopic member loses pressure. Since the temperature of the metal tube 6 is still high and the second inner cylinder 12 does not contract, the first telescopic member will not contract.

[0078] Only when the temperature of the metal tube 6 also drops and the second telescopic member also contracts, under the pulling force of the tension spring 13, will the first telescopic member contract.

[0079] In this way, the heat stored in the metal tube 6 can be effectively utilized after night falls.

[0080] The technical features not described in the present utility model can be achieved by or adopted from the prior art, and will not be elaborated here. Of course, the above description is not a limitation of the present utility model, and the present utility model is not limited to the above examples. Changes, modifications, additions or substitutions made by those of ordinary skill in the art within the essence of the present utility model should also fall within the protection scope of the present utility model.

Claims

1. A heat pipe collector with a heat storage device, characterized in that: It comprises a double-layer vacuum glass tube, wherein the outer layer of the double-layer vacuum glass tube is a transparent glass layer, and the inner layer surface is coated with a selective absorption coating; The double-layer vacuum glass tube is internally connected with a heat conducting member, the heat conducting member is connected with a heat pipe, the heat pipe comprises a condensation section, an insulation section and an evaporation section, the evaporation section is located at the axial center of the double-layer vacuum glass tube; The heat-conducting member comprises a heat-conducting fin, the heat-conducting fin is tile-shaped, and the outer side of the heat-conducting fin is in close contact with the inner layer of the double-layer vacuum glass tube; The heat conducting member further comprises an inner heat conducting portion, the inner heat conducting portion is shaped like a long straight through notch cut out between the two ends of the cylinder, and the inner surface of the inner heat conducting portion is closely connected with the heat pipe; The heat conducting member is connected to a metal tube for thermal conduction, and a phase change heat storage capsule is arranged in the metal tube.

2. A heat pipe collector with a heat storage device according to claim 1, characterized in that: The heat-conducting fin is connected to a first connecting piece, the first connecting piece is connected to a middle heat-conducting tile, the middle heat-conducting tile is connected to a second connecting piece, and the second connecting piece is connected to the inner heat-conducting part; The angle between the heat conducting fin and the first connecting piece is an acute angle; The angle between the first connecting piece and the outer side of the middle heat conducting tile is an acute angle; The included angle between the second connecting piece and the outer side of the middle heat conducting tile is an obtuse angle; The angle between the second connecting piece and the outer side of the inner heat conducting part is an acute angle; When the metal tube is connected to the heat conducting member, the inner side of the middle heat conducting tile is in close contact with the metal tube.

3. A heat pipe collector with a heat storage device according to claim 2, characterized in that: The heat conducting member comprises two heat conducting fins, and a first connecting piece, a middle heat conducting tile and a second connecting piece are connected between the two heat conducting fins and the inner heat conducting part.

4. The heat pipe collector with a heat storage device according to claim 1, characterized in that: The diameter of the metal pipe is larger than the diameter of the heat pipe, and the material of the metal pipe is steel, aluminum or stainless steel.

5. The heat pipe collector with a heat storage device according to claim 1, characterized in that: The length of the metal tube is less than or equal to the length of the heat conducting fin.

6. The heat pipe collector with a heat storage device according to claim 1, characterized in that: The phase change temperature of the phase change heat storage capsule is 60-80°C.

7. The heat pipe collector with a heat storage device according to claim 1, characterized in that: The phase change heat storage capsule occupies 60-80% of the volume of the metal tube.

8. The heat pipe collector with a heat storage device according to claim 2, characterized in that: The heat-conducting fin is connected to a first telescopic member, the first telescopic member includes a first inner tube, the first inner tube is slidably sleeved with a first outer tube, and the first outer tube is connected to the metal tube; A first elastic bag is disposed between the first inner tube and the first outer tube, and a first gas-liquid phase change material is disposed in the inner cavity of the first elastic bag, and the evaporation temperature of the first gas-liquid phase change material is greater than a first set temperature; The outer wall of the metal tube is located at the inner cavity of the first outer tube and is connected to a second telescopic member, the second telescopic member comprises a second outer tube, and the second outer tube is slidably sleeved with a second inner tube; A second elastic bag is disposed between the second inner tube and the second outer tube, and a second gas-liquid phase change material is disposed in the inner cavity of the second elastic bag, and the evaporation temperature of the second gas-liquid phase change material is greater than the second set temperature; When the first telescopic member is extended, the second telescopic member is also extended, and the second inner tube presses against the end of the first inner tube, thereby preventing the first telescopic member from contracting; A tension spring is connected between the metal tube and the heat-conducting fin close to the first telescopic member.

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