Variable-frequency energy-saving alternating-current electric furnace

Abstract

The variable-frequency energy-saving alternating-current electric furnace comprises a furnace body, and a preheating chamber, an annealing chamber and a cooling chamber which are sequentially communicated are arranged in the furnace body. A transmission mechanism which sequentially penetrates through the preheating chamber, the annealing chamber and the cooling chamber is arranged in the furnace body; an evaporation pipe is arranged in the cooling chamber, a condensation pipe is arranged in the preheating chamber, the evaporation pipe is communicated with the condensation pipe through a pipeline A and a pipeline B, the pipeline A is provided with a one-way check valve A with an opening facing the condensation pipe, the pipeline B is provided with a one-way check valve B with an opening facing the evaporation pipe, and the condensation pipe is connected with the pipeline B through a compression device. The temperature in the cooling chamber and the temperature in the preheating chamber are adjusted through the evaporation pipe, the condensation pipe and the compression device, waste heat of a workpiece in the cooling chamber is transmitted into the preheating chamber to preheat the workpiece in the preheating chamber, and heat energy loss is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of annealing equipment, in particular to a variable frequency energy-saving alternating current electric furnace. Background Art

[0002] The variable frequency energy-saving AC furnace is a highly efficient, energy-saving, environmentally friendly and safe electric furnace equipment. By adopting variable frequency technology, the electric furnace can adjust the heating power according to actual needs, accurately control the temperature, reduce energy consumption and improve energy efficiency.

[0003] Prior art application number 202310853689.1 discloses a high-efficiency continuous recrystallization annealing equipment and method, including a loading table, an inlet preheating chamber... A combustion module is installed on the upper end of the heating chamber close to the first transition section; the heat energy loss is reduced by the rollers that always rotate in the furnace, and the hot air in the heat exchange chamber is transported to the preheating chamber through a fan and a connecting pipe to preheat the workpiece.

[0004] However, the above technical solution has some problems: the fan can only take away the heat emitted by the workpiece, but cannot accelerate the cooling of the workpiece. The workpiece needs to be cooled in a cooling chamber, which leads to heat energy loss. The cooling chamber needs to consume a certain amount of energy to cool the workpiece, and effective energy saving cannot be achieved. Each compartment is separated by a sealed door, which makes the equipment more complicated and increases the production cost of the equipment. The reciprocating opening and closing of multiple sealed doors also increases energy consumption. Utility Model Content

[0005] The utility model aims at the deficiencies in the prior art and provides a variable frequency energy-saving AC electric furnace which adjusts the temperatures in a cooling chamber and a preheating chamber by means of an evaporating tube, a condensing tube and a compression device, transfers the waste heat of the workpiece in the cooling chamber to the preheating chamber, preheats the workpiece in the preheating chamber, reduces heat energy loss, and is simple, efficient, safe, reliable and easy to operate.

[0006] The utility model is realized by the following technical scheme, and provides a variable frequency energy-saving AC electric furnace, including a furnace body, a material conveying channel is opened in the furnace body, and a heat-insulating layer is arranged on the inner wall of the material conveying channel; a heat-insulating mechanism A, a heat-insulating mechanism B, a heat-insulating mechanism C and a heat-insulating mechanism D are arranged in sequence in the material conveying channel, a preheating chamber is formed between the heat-insulating mechanism A and the heat-insulating mechanism B, an annealing chamber is formed between the heat-insulating mechanism B and the heat-insulating mechanism C, and a cooling chamber is formed between the heat-insulating mechanism C and the heat-insulating mechanism D; an insulating layer and an electromagnetic heating mechanism are arranged in sequence on the outer side of the annealing chamber; a heat-insulating mechanism A is arranged in the material conveying channel along the material conveying channel, and a heat-insulating mechanism B is arranged between the heat-insulating mechanism B and the heat-insulating mechanism C, and a heat-insulating mechanism C is arranged between the heat-insulating mechanism D ... a heat-insulating mechanism B is arranged between the heat-insulating mechanism B and the heat-insulating mechanism C, and a heat-insulating mechanism C is arranged between a transmission mechanism extending in the extension direction of the material channel; an evaporating tube is arranged in the cooling chamber, a condensing tube is arranged in the preheating chamber, the evaporating tube is connected with the condensing tube through a pipe A and a pipe B respectively, and a one-way check valve A with an opening toward the condensing tube is arranged on the pipe A, a one-way check valve B with an opening toward the evaporating tube is arranged on the pipe B, and the condensing tube is connected with the pipe B through a compression device; the temperatures in the cooling chamber and the preheating chamber are adjusted by the evaporating tube, the condensing tube and the compression device, the waste heat of the workpiece in the cooling chamber is transferred to the preheating chamber, the workpiece in the preheating chamber is preheated, and the heat energy loss is reduced.

[0007] As an optimization, the insulation mechanism A, the insulation mechanism B, the insulation mechanism C and the insulation mechanism D all include an upper insulation board, the top of the upper insulation board is connected to the top of the feed channel, the two sides of the upper insulation board are arranged to fit the inner walls of the two sides of the feed channel, and the bottom of the upper insulation board is located above the transmission mechanism; the upper insulation board adopts a flexible high-temperature resistant and fireproof insulation material; the upper insulation board is used to reduce the energy consumption of opening or closing the feed channel during the transmission of workers and materials.

[0008] As an optimization, the transmission mechanism includes a bracket, on which rollers arranged in sequence along the transmission direction are rotated, and the insulation mechanism A, the insulation mechanism B, the insulation mechanism C and the insulation mechanism D are respectively located between adjacent rollers; the bracket is provided with a driving mechanism for driving the rollers to rotate; by means of rollers that are always located in the preheating chamber, the annealing chamber and the cooling chamber, respectively, the heat energy loss during the material transmission process is reduced.

[0009] As an optimization, the rollers in the cooling chamber and the preheating chamber are of hollow structure, and the inner cavity of the roller in the cooling chamber is connected with the inner cavity of the roller in the preheating chamber through pipe A and pipe B respectively; the rollers in the cooling chamber and the preheating chamber are in direct contact with the work material and are interconnected to accelerate the transfer of heat energy on the work material in the cooling chamber to the work material in the cold preheating chamber.

[0010] As an optimization, heat sinks are fixed on the condenser and the evaporator, and the heat sinks are arranged around the condenser and the evaporator. The heat sinks arranged around the condenser and the evaporator increase the contact area between the condenser and the evaporator and the air, thereby accelerating the transfer of heat energy.

[0011] The beneficial effects of the utility model are as follows: the temperatures in the cooling chamber and the preheating chamber are adjusted by the evaporator, the condenser and the compression device, and the waste heat of the workpiece in the cooling chamber is transferred to the preheating chamber to preheat the workpiece in the preheating chamber, thereby reducing the heat energy loss; the energy consumption of opening or closing the material conveying channel during the work-material transmission is reduced by the upper insulation board; the heat energy on the workpiece in the cooling chamber is transferred to the workpiece in the cold preheating chamber by rollers in the cooling chamber and the preheating chamber that are in direct contact with the workpiece and are interconnected; the contact area between the condenser and the evaporator and the air is increased by the heat sinks arranged around the condenser and the evaporator, thereby accelerating the heat energy transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the structure of the utility model (I);

[0013] Figure 2 This is a schematic diagram of the structure of the utility model (II);

[0014] Figure 3 It is a schematic diagram of the transmission mechanism, transmission mechanism and driving mechanism of the utility model;

[0015] Figure 4 This is a schematic diagram of the evaporation tube and condensation tube structure of the utility model.

[0016] As shown in the figure:

[0017] 1. furnace body, 2. insulation layer, 3. insulation mechanism A, 4. insulation mechanism B, 5. insulation mechanism C, 6. insulation mechanism D, 7. preheating chamber, 8. annealing chamber, 9. cooling chamber, 10. insulation layer, 11. electromagnetic heating mechanism, 12. transmission mechanism, 13. evaporation tube, 14. condenser, 15. pipeline A, 16. pipeline B, 17. one-way check valve A, 18. one-way check valve B, 19. compression device, 20. heat sink, 21. transmission mechanism, 22. driving mechanism, 301. upper insulation board, 302. lower insulation board, 1201. bracket, 1202. roller, 2101. transmission wheel, 2102. transmission belt. DETAILED DESCRIPTION

[0018] In order to clearly illustrate the technical features of this solution, this solution is described below through a specific implementation method.

[0019] like Figure 1 and Figure 2The variable frequency energy-saving AC electric furnace of the utility model shown in the figure comprises a furnace body 1, a material conveying channel is provided in the furnace body 1, and a heat preservation layer 2 is provided on the inner wall of the material conveying channel; a heat insulation mechanism A3, a heat insulation mechanism B4, a heat insulation mechanism C5 and a heat insulation mechanism D6 are arranged in sequence in the material conveying channel, a preheating chamber 7 is formed between the heat insulation mechanism A3 and the heat insulation mechanism B4, an annealing chamber 8 is formed between the heat insulation mechanism B4 and the heat insulation mechanism C5, and a cooling chamber 9 is formed between the heat insulation mechanism C5 and the heat insulation mechanism D6; the outer side of the annealing chamber 8 is provided with an insulation layer 1 in sequence 0 and an electromagnetic heating mechanism 11; a transmission mechanism 12 extending along the extension direction of the material conveying channel is provided in the material conveying channel; an evaporating tube 13 is provided in the cooling chamber 9, a condensing tube 14 is provided in the preheating chamber 7, the evaporating tube 13 is connected with the condensing tube 14 through a pipeline A15 and a pipeline B16 respectively, and a one-way check valve A17 with an opening toward the condensing tube 14 is provided on the pipeline A15, and a one-way check valve B18 with an opening toward the evaporating tube 13 is provided on the pipeline B16, and the condensing tube 14 is connected with the pipeline B16 through a compression device 19.

[0020] The transmission mechanism 12 extends to the outside of the feed channel along the extension direction of the feed channel; the evaporation tube 13, the condensation tube 14, the pipeline A15 and the pipeline B16 are provided with a medium for transferring heat, and the medium adopts a refrigerant, such as Freon (fluorine, chlorine, and bromine derivatives of saturated hydrocarbons), an azeotropic mixed working fluid (an azeotropic solution formed by mixing two Freons in a certain proportion), hydrocarbons (propane, ethylene, etc.), ammonia, etc.; the evaporation tube 13 is arranged in sequence along the inner wall of the cooling chamber 9, and the condensation tube 14 is arranged in sequence along the inner wall of the preheating chamber 7; the condensation tube 14 is connected to the medium inlet of the compression device 19, and the medium outlet of the compression device 19 is connected to the pipeline B16.

[0021] The work material is placed on the transmission mechanism 12 and transmitted to the annealing chamber 8 through the transmission mechanism 12; after the work material is annealed in the annealing chamber 8, it is transmitted to the cooling chamber 9 through the transmission mechanism 12 through the insulation mechanism C5, the work material that has completed annealing releases heat, the temperature in the cooling chamber 9 gradually increases, the medium in the evaporation tube 13 evaporates, absorbs the heat in the cooling chamber 9, gradually reduces the temperature in the cooling chamber 9, and accelerates the release of the heat emitted by the work material that has completed annealing; the evaporated medium passes through the one-way check valve A17 through the pipeline A15 and enters the condenser 14, the medium releases heat, the temperature in the preheating chamber 7 gradually increases and the work material in the preheating chamber 7 is preheated; the compression device 19 is started, the compression device 19 compresses the medium in the condenser 14 into a liquid state, the medium releases a large amount of heat into the preheating chamber 7, and accelerates the preheating of the work material in the preheating chamber 7; the liquid medium in the compression device 19 passes through the one-way check valve B18 through the pipeline B16 and enters the cooling chamber 9, starting the next round of waste heat transfer.

[0022] like Figure 1The insulation mechanism A3, insulation mechanism B4, insulation mechanism C5 and insulation mechanism D6 shown in the figure all include an upper insulation board 301, the top of the upper insulation board 301 is connected to the top of the feed channel, the two sides of the upper insulation board 301 are fitted with the inner walls of the two sides of the feed channel, and the bottom of the upper insulation board 301 is located above the transmission mechanism 12; the upper insulation board 301 adopts a flexible high-temperature resistant and fireproof insulation material, such as aluminum silicate fiber felt, and the maximum operating temperature can reach 1300°C. The temperature range of the annealing furnace is 300°C to 1200°C; the bottom of the upper insulation board 301 is fitted with the upper transmission surface of the transmission mechanism 12.

[0023] The work material is placed on the conveying mechanism 12, and the conveying mechanism 12 is started, and the work material is conveyed on the conveying mechanism 12; when the work material passes through the upper insulation board 301, the bottom of the upper insulation board 301 gradually moves along the conveying direction of the conveying mechanism 12 with the work material, until a channel sufficient for the work material to pass through is formed between the bottom of the upper insulation board 301 and the upper conveying surface of the conveying mechanism 12, and the work material passes through the channel formed between the bottom of the insulation mechanism A3 and the upper conveying surface of the conveying mechanism 12, and enters the preheating chamber 7 for preheating; the work material passes through the channel formed between the bottom of the insulation mechanism B4 and the upper conveying surface of the conveying mechanism 12, and enters the annealing chamber 8 for annealing; the work material passes through the channel formed between the bottom of the insulation mechanism C5 and the upper conveying surface of the conveying mechanism 12, and enters the cooling chamber 9 for cooling; the work material passes through the channel formed between the bottom of the insulation mechanism D6 and the upper conveying surface of the conveying mechanism 12, and completes cooling.

[0024] like Figure 1 and Figure 3 The transmission mechanism 12 shown includes a bracket 1201, on which rollers 1202 arranged in sequence along the transmission direction are rotated, and the heat insulation mechanism A3, the heat insulation mechanism B4, the heat insulation mechanism C5 and the heat insulation mechanism D6 are respectively located between adjacent rollers 1202; the bracket 1201 is provided with a driving mechanism 22 for driving the rollers 1202 to rotate; the driving mechanism 22 is connected to the rollers 1202 in sequence through the transmission mechanism 21, and the driving mechanism 22 adopts a motor; the transmission mechanism 21 includes a coaxial fixed roller 1202 The transmission wheel 2101 is connected to the output shaft of the motor through the transmission belt 2102; the heat insulation mechanism A3, the heat insulation mechanism B4, the heat insulation mechanism C5 and the heat insulation mechanism D6 also include a lower heat insulation board 302, the lower heat insulation board 302 is located between adjacent rollers 1202, and the bottom of the lower heat insulation board 302 is connected to the bottom of the feeding channel, the two sides of the lower heat insulation board 302 are connected to the inner walls of the two sides of the feeding channel, and the top of the lower heat insulation board 302 is fitted with the bottom of the upper heat insulation board 301.

[0025] The work material is placed on the roller 1202, and the driving mechanism 22 is started. The driving mechanism 22 drives the roller 1202 to rotate synchronously through the transmission belt 2102 and the transmission wheel 2101, and the work material is transmitted on the roller 1202; the work material passes between the upper insulation board 301 and the lower insulation board 302.

[0026] like Figure 1 and Figure 2 The roller 1202 provided in the cooling chamber 9 and the preheating chamber 7 is a hollow structure, and the inner cavity of the roller 1202 in the cooling chamber 9 is connected with the inner cavity of the roller 1202 in the preheating chamber 7 through the pipeline A15 and the pipeline B16 respectively; the inner cavity of the roller 1202 in the cooling chamber 9 is connected to the end of the pipeline A15 and the pipeline B16 close to the cooling chamber 9 respectively; the inner cavity of the roller 1202 in the preheating chamber 7 is connected to the end of the pipeline A15 and the pipeline B16 close to the preheating chamber 7 respectively.

[0027] The work material is placed on the roller 1202 of the transmission mechanism 12 and is transmitted to the annealing chamber 8 through the roller 1202; after the work material is annealed in the annealing chamber 8, it is transmitted to the cooling chamber 9 through the roller 1202 through the insulation mechanism C5, the work material that has completed annealing releases heat, the roller 1202 in the cooling chamber 9 absorbs heat, and the medium of the roller 1202 in the cooling chamber 9 evaporates and absorbs the heat absorbed by the work material; the evaporated medium passes through the pipeline A15 and the one-way check valve A17 into the roller 1202 in the preheating chamber 7, and the medium releases heat and preheats the work material in the preheating chamber 7; the compression device 19 is started, and the compression device 19 compresses the medium in the roller 1202 in the preheating chamber 7 into a liquid state, and the medium releases a large amount of heat into the preheating chamber 7, accelerating the preheating of the work material in the preheating chamber 7; the liquid medium in the compression device 19 passes through the one-way check valve B18 and enters the cooling chamber 9 via the pipeline B16, starting the next round of waste heat transfer.

[0028] like Figure 1 and Figure 4 As shown, both the condenser tube 14 and the evaporator tube 13 are provided with heat sinks 20, which are arranged around the condenser tube 14 and the evaporator tube 13; the heat in the cooling chamber 9 is quickly transferred to the evaporator tube 13 through the heat sinks 20 on the evaporator tube 13, and the medium in the condenser tube 14 is quickly released into the preheating chamber 7 through the heat sinks 20 on the condenser tube 14.

[0029] In the actual production process, the work material is placed on the roller 1202 at the input end of the transmission mechanism 12, and the driving mechanism 22 is started. The driving mechanism 22 drives the roller 1202 to rotate synchronously through the transmission belt 2102 and the transmission wheel 2101. The work material is transmitted on the roller 1202 along the transmission direction of the transmission mechanism 12 and is transmitted to the annealing chamber 8 for annealing; after the annealing is completed, the work material passes through the insulation mechanism C5 under the transmission of the roller 1202, and the bottom of the upper insulation board 301 of the insulation mechanism C5 gradually moves along the transmission direction of the transmission mechanism 12 with the work material, until a channel sufficient for the work material to pass through is formed between the bottom of the upper insulation board 301 of the insulation mechanism C5 and the upper transmission surface of the transmission mechanism 12, and the work material passes between the upper insulation board 301 and the lower insulation board 302 of the insulation mechanism C5 and enters the cooling chamber 9.

[0030] The workpiece that has completed annealing releases heat in the cooling chamber 9, and the temperature in the cooling chamber 9 gradually increases. The evaporator tube 13 absorbs the heat in the cooling chamber 9 through the heat sink 20 on the evaporator tube 13. The medium in the evaporator tube 13 gradually evaporates after absorbing the heat, and the temperature in the cooling chamber 9 gradually decreases, accelerating the release of the heat emitted by the workpiece that has completed annealing; at the same time, the roller 1202 in the cooling chamber 9 directly absorbs heat from the workpiece that has completed annealing, accelerating the annealing of the workpiece, and the medium of the roller 1202 in the cooling chamber 9 evaporates and absorbs the heat absorbed by the workpiece.

[0031] The work material that has completed cooling passes through the insulation mechanism D6 under the transmission of the roller 1202. The bottom of the upper insulation plate 301 of the insulation mechanism D6 gradually moves along the transmission direction of the transmission mechanism 12 with the work material, until a channel sufficient for the work material to pass through is formed between the bottom of the upper insulation plate 301 of the insulation mechanism D6 and the upper transmission surface of the transmission mechanism 12. The work material passes between the upper insulation plate 301 and the lower insulation plate 302 of the insulation mechanism D6, and is discharged from the furnace body 1 from the output end of the work material transmission mechanism 12.

[0032] The work material placed on the roller 1202 at the input end of the transmission mechanism 12 passes through the insulation mechanism A3 under the transmission of the roller 1202, and the bottom of the upper insulation board 301 of the insulation mechanism A3 gradually moves along the transmission direction of the transmission mechanism 12 with the work material, until a channel sufficient for the work material to pass through is formed between the bottom of the upper insulation board 301 of the insulation mechanism A3 and the upper transmission surface of the transmission mechanism 12, and the work material passes between the upper insulation board 301 and the lower insulation board 302 of the insulation mechanism A3 and enters the preheating chamber 7.

[0033] The evaporated medium passes through the one-way check valve A17 via the pipeline A15 and enters the condenser 14 and the roller 1202 in the preheating chamber 7. The medium in the roller 1202 in the preheating chamber 7 releases heat and directly preheats the work materials in the preheating chamber 7; at the same time, the medium in the condenser 14 quickly releases heat through the heat sink 20 on the condenser 14 and preheats the work materials in the preheating chamber 7; the compression device 19 is started, and the compression device 19 compresses the medium in the roller 1202 in the preheating chamber 7 into a liquid state. The medium releases a large amount of heat into the preheating chamber 7 through the roller 1202 in the preheating chamber 7 and the condenser 14, thereby accelerating the preheating of the work materials in the preheating chamber 7.

[0034] The preheated workpiece passes through the heat insulation mechanism B4 under the transmission of the roller 1202. The bottom of the upper insulation plate 301 of the heat insulation mechanism B4 gradually moves along the transmission direction of the transmission mechanism 12 with the workpiece, until a channel sufficient for the workpiece to pass through is formed between the bottom of the upper insulation plate 301 of the heat insulation mechanism B4 and the upper transmission surface of the transmission mechanism 12. The workpiece passes between the upper insulation plate 301 and the lower insulation plate 302 of the heat insulation mechanism B4 and enters the preheating chamber 7.

[0035] The liquid medium compressed by the compression device 19 enters the cooling chamber 9 via the pipeline B16 and passes through the one-way check valve B18, starting the next round of waste heat transfer.

[0036] Of course, the above description is not limited to the above examples. The technical features not described in the present invention can be achieved by or by adopting the existing technology, which will not be repeated here. The above embodiments and drawings are only used to illustrate the technical scheme of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that the changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not deviate from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention.

Claims

1. A variable frequency energy-saving AC electric furnace, comprising a furnace body (1), a material conveying channel is provided in the furnace body (1), and a heat insulation layer (2) is provided on the inner wall of the material conveying channel; a heat insulation mechanism A (3), a heat insulation mechanism B (4), a heat insulation mechanism C (5) and a heat insulation mechanism D (6) are arranged in sequence in the material conveying channel, a preheating chamber (7) is formed between the heat insulation mechanism A (3) and the heat insulation mechanism B (4), an annealing chamber (8) is formed between the heat insulation mechanism B (4) and the heat insulation mechanism C (5), and a cooling chamber (9) is formed between the heat insulation mechanism C (5) and the heat insulation mechanism D (6); an insulating layer (10) and an electromagnetic heating mechanism (11) are provided in sequence on the outer side of the annealing chamber (8); a transmission mechanism (12) extending along the extending direction of the material conveying channel is provided in the material conveying channel; the characteristics are as follows: An evaporation tube (13) is provided in the cooling chamber (9), and a condensation tube (14) is provided in the preheating chamber (7). The evaporation tube (13) is connected to the condensation tube (14) through a pipe A (15) and a pipe B (16), respectively. A one-way check valve A (17) with an opening toward the condensation tube (14) is provided on the pipe A (15), and a one-way check valve B (18) with an opening toward the evaporation tube (13) is provided on the pipe B (16). The condensation tube (14) is connected to the pipe B (16) through a compression device (19).

2. The variable frequency energy-saving AC electric furnace according to claim 1, characterized in that: The heat insulation mechanism A (3), the heat insulation mechanism B (4), the heat insulation mechanism C (5) and the heat insulation mechanism D (6) all include an upper heat insulation plate (301), the top of the upper heat insulation plate (301) is connected to the top of the material conveying channel, the two sides of the upper heat insulation plate (301) are arranged to fit the inner walls of the two sides of the material conveying channel, and the bottom of the upper heat insulation plate (301) is located above the transmission mechanism (12).

3. The variable frequency energy-saving AC electric furnace according to claim 2, characterized in that: The transmission mechanism (12) comprises a support (1201), on which rollers (1202) arranged in sequence along a transmission direction are rotatably mounted, and a heat insulation mechanism A (3), a heat insulation mechanism B (4), a heat insulation mechanism C (5) and a heat insulation mechanism D (6) are respectively located between adjacent rollers (1202); and a driving mechanism (22) for driving the rollers (1202) to rotate is mounted on the support (1201).

4. The variable frequency energy-saving AC electric furnace according to claim 1, characterized in that: The rollers (1202) provided in the cooling chamber (9) and the preheating chamber (7) are of a hollow structure, and the inner cavity of the roller (1202) in the cooling chamber (9) is connected to the inner cavity of the roller (1202) in the preheating chamber (7) through a pipe A (15) and a pipe B (16), respectively.

5. The variable frequency energy-saving AC electric furnace according to claim 1, characterized in that: The condenser tube (14) and the evaporator tube (13) are both fixedly provided with heat sinks (20), and the heat sinks (20) are arranged around the condenser tube (14) and the evaporator tube (13).

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