JP2834302B2 - Heat exchanger - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger in which a refrigerant is heated by a high-temperature gas such as a combustion gas and used for, for example, a heating and cooling device.

2. Description of the Related Art A circuit configuration as shown in FIG. 4 is used for cooling using a cooling medium as a fluid to be heated, heating it with a combustion gas to vaporize a liquid refrigerant, carrying heat by latent heat, and heating. There is a refrigerant heating heater. In this method, a heat exchanger 1 for exchanging heat between a combustion gas and a refrigerant and a radiator 2 are connected by a closed conduit 3, and the refrigerant is forcibly circulated by a refrigerant carrier 4 provided in the closed conduit 3. .

However, in the heating system as shown in FIG. 4, external power is required for transporting the refrigerant, and it is desired to reduce the running cost during the heating operation.

Problems to be Solved by the Invention To reduce the running cost during the heating operation, it is effective to eliminate the external power for transporting the refrigerant and carry out the heat transport without power. In the case of performing heating and heating of a refrigerant by non-powered heat transfer, natural circulation force due to buoyancy of a gas refrigerant generated by heating a liquid refrigerant is important.

Conventionally, a heat exchanger having a configuration as shown in FIG. 5 is used for this type of heating device.

FIG. 5 shows a conventional example of the heat exchanger 1 (Japanese Unexamined Patent Publication No.
59-107167), a plurality of fins 5 provided on an inner peripheral surface of a cylindrical body extending in a horizontal direction, and an axial pipe holding portion 6 and a pipe 7 through which a refrigerant flows inside are provided on an outer peripheral surface. The combustion gas from the burner 8 flows in the horizontal direction to the inner surface of the cylindrical body, and heats the refrigerant that is sent by the refrigerant carrier 4 and flows through the pipe 7. Reference numeral 9 denotes a temperature detector, which is attached to the surface between the pipe holding portions 6, and controls to stop heating when the temperature of the refrigerant abnormally rises.

At this time, since the refrigerant flows through the pipe 7 extending in the horizontal direction, the gas component of the refrigerant in a heated and gas-liquid two-phase mixed state does not flow smoothly toward the outlet, and therefore, the refrigerant stagnates and the refrigerant locally Abnormal overheating occurs, or because the combustion chamber and the heat exchange unit are integrated, the heat exchange amount becomes uneven depending on the combustion state, causing local overheating, causing thermal decomposition of the refrigerant or abnormal temperature of the equipment. As a result, there was a problem in the reliability performance of the equipment.

The present invention solves such a conventional problem, in which a natural circulation cycle of a refrigerant heater overheated by a burner or the like is smoothly circulated by an increase in natural circulation force due to bubble rise, and refrigerant is insufficient in the refrigerant heater. If the refrigerant overheats in some cases, it is immediately detected to normalize the operation of the system.At the same time, if an abnormality occurs in the temperature detection or the operation controlled by this output, the safety is maintained. It is an object to provide a heat exchanger that can be protected.

Means for Solving the Problems In order to solve the above problems, a heat exchanger of the present invention comprises a hot gas passage member having a fire spread gas inlet communicating with a combustion chamber of a burner, and a hot gas passage member on an inner surface facing the combustion chamber. A heat transfer partition having a passage member closely attached thereto, integrally formed at a position corresponding to the high-temperature gas passage member on an outer surface of the heat transfer partition,
A refrigerant passage member having a plurality of vertical refrigerant passages, and header tubes provided at both upper and lower ends of the refrigerant passage member,
A refrigerant inlet pipe and a refrigerant outlet pipe attached to each of the header pipes, a temperature detection means provided in the refrigerant passage member at a position opposite to the refrigerant outlet pipe, and a side near the refrigerant outlet pipe. A temperature-sensitive switch provided at the position in the refrigerant passage member.

Function The present invention can smoothly circulate a natural circulation cycle of a refrigerant heater heated by a burner or the like by an increase in a natural circulation force due to rising of bubbles in a plurality of refrigerant passages, and Is not locally heated, and the non-powered heat transfer is reliably performed, so that the refrigerant is not thermally decomposed. The flow of the refrigerant flows from the refrigerant inlet pipe, is divided into the respective refrigerant passages of the refrigerant passage member at the inlet header pipe, and receives the heat of the high-temperature gas flowing in the high-temperature gas passage member in the middle of the refrigerant passage to generate a gas. And
After that, they gather at the outlet header pipe and flow from the refrigerant outlet pipe to the refrigerant circuit. At this time, the refrigerant flowing through the inlet header pipe has a large liquid phase, and the refrigerant flowing through the outlet header pipe receives heat, so that the gas phase increases, and the flow resistance in the cooling header pipe becomes larger than that in the inlet header pipe. For this reason, the amount of the refrigerant flowing through each of the refrigerant passages of the refrigerant passage member flows more toward the refrigerant outlet tube, and the flow rate of the refrigerant flowing through the refrigerant passage at a position opposite to the refrigerant outlet tube is minimized. Therefore, when the amount of the refrigerant is less than the predetermined amount, all of the refrigerant is vaporized (gasified) and the temperature rises due to sensible heat. Therefore, by providing the temperature detection means in the refrigerant passage member at a position opposite to the refrigerant outlet pipe, when the refrigerant is overheated, such as when the flow rate of the refrigerant is insufficient in the refrigerant heater, the temperature detection means Immediately detect this and normalize the operation of the system,
Thermal decomposition and deterioration of the refrigerant can be prevented. Further, the amount of the refrigerant flowing through each of the refrigerant passages of the refrigerant passage member flows more toward the refrigerant outlet pipe, and therefore, the refrigerant flowing through the refrigerant passage member at a position closer to the refrigerant outlet pipe becomes the largest, and the refrigerant is heated. When the vessel is exhausted, a temperature rise due to sensible heat occurs at this location. Therefore, when an abnormality occurs in the operation of controlling the temperature detection or the output by this output, the temperature-sensitive switch provided in the refrigerant passage member at a position near the refrigerant outlet pipe detects this, maintaining safety, Equipment can be protected and a highly reliable system can be obtained.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially cutaway perspective view of a heat exchanger showing one embodiment of the present invention, FIG. 2 is a sectional view of a high-temperature gas passage member and a refrigerant passage member of the heat exchanger, and FIG. It is a rear view of an exchanger.

1 to 3, reference numeral 10 denotes a combustion chamber which communicates with a burner 8 connected to a fuel supply device, and a heat transfer partition 11 is attached to face the combustion chamber 10. Reference numeral 12 denotes a high-temperature gas passage member, which is attached to the combustion chamber 10 in close contact with the inner surface of the heat transfer partition 11 and communicates with the combustion chamber 10 to take in the high-temperature combustion gas. And an exhaust outlet 14 communicating with the exhaust port. Reference numeral 15 denotes a refrigerant passage member which is thermally connected to the outer surface of the heat transfer partition 11 and is mounted corresponding to the high-temperature gas passage member 12, and is provided with a large number of vertical refrigerant passages 16. Reference numeral 17 denotes an inlet header pipe provided at the lower end of the refrigerant passage member 16, and 18 denotes an outlet header pipe provided at the upper end of the refrigerant passage member 16, a refrigerant inlet pipe 19 and a refrigerant outlet 20 extending in the same direction, respectively. The inlet header pipe 17 is provided at the other end thereof with an oil drain pipe 21 bent downward. Also, inlet header pipe
The 17 and the outlet header tube 18 communicate with each other through the refrigerant passage 16 in the up and down direction of the refrigerant passage member 16. Reference numeral 22 denotes a number of heat transfer fins provided so as to be in thermal contact with the inside of the heat transfer partition 11.When the combustion chamber 10 is attached to the heat transfer partition 11, the outer frame of the combustion chamber 10 is The both sides of the passage member 12 except for the combustion gas inlet 13 and the exhaust outlet 14 are pressed to thermally couple the high temperature gas passage member 12 together with the heat transfer fins 22 to the heat transfer partition 11. Further, a heat insulating material 23 covering the entire surface is provided on the remaining inner surface of the combustion chamber 10 which is not in contact with the high temperature gas passage member 12. A temperature thermistor 24 as a temperature detecting means is provided above the refrigerant passage member 15 at a position opposite to the refrigerant outlet pipe 20,
A temperature-sensitive temperature switch 25 is provided above the refrigerant passage member 15 at a position close to the refrigerant outlet pipe 20, respectively.
It is attached by using a metal fitting 26 closely fixed to the main body. In this embodiment, the temperature-sensitive temperature switch 25 is
It is screwed to 26 and is in close contact with the refrigerant passage member 15.
27 is a controller for controlling the system based on the detection outputs of the temperature thermistor 24 and the temperature switch 25.

In the above configuration, the fuel supplied from the fuel supply device is burned by the burner 8, and the high-temperature combustion gas generated in the combustion chamber 10 enters through the combustion gas inlet 13 and includes the space between the heat transfer fins 22 of the high-temperature gas passage member 12. After passing through the passage, it flows from the exhaust outlet 14 to the exhaust passage 28 and is discharged from the exhaust pipe 29. Refrigerant inlet pipe 19
The liquid refrigerant that has entered the inlet header pipe 17 flows through the lower portion of the refrigerant passage member 15 into a number of vertical refrigerant passages 16 and flows therefrom. The heat is transferred by the heat transferred to the refrigerant passage material passage 15 through the heat transfer partition 11. At this time, the refrigerant in the refrigerant passage 16 in the vertical direction of the refrigerant passage member 15
Heated well from the bottom near 17. Then, the heated liquid refrigerant starts vaporizing and evaporating, and enters a gas-liquid two-phase state in which bubbles are generated in the liquid, and the generated bubbles rise upward from below in the vertical refrigerant passage 16 by a buoyancy effect. In particular, the combustion gas directly enters the combustion gas inlet 13 from the combustion chamber 10 and transfers heat to the high-temperature gas passage member 12, so that the temperature and flow of the combustion gas become uniform, and each part of the refrigerant passage member 15 can be uniformly heated, and can be smoothly and smoothly. The refrigerant is uniformly evaporated, and the refrigerant does not locally overheat. Therefore, the non-powered heat transfer is reliably performed, and the thermal decomposition of the refrigerant does not occur. Then, the flow rate of each of the refrigerant passages 16 is made uniform by uniform heating to reduce the resistance as a whole, the bubble rising force is strengthened, the natural circulation force is strengthened, and a bubble pump action for sending the refrigerant upward is generated. In addition, the entire surface of the heat transfer partition 11 other than the heat transfer fins 22 at the upper and lower portions of the refrigerant passage 16 serves as a heat transfer area, further heating the gas-liquid two-phase refrigerant in the refrigerant passage 16 and further increasing the natural circulation force. Let it. The refrigerant that has reached the upper end of the refrigerant passage 16 flows into the outlet header tube 18 and flows out of the refrigerant outlet tube 20 toward a radiator (not shown).

Further, the refrigerant passage member 16 is formed by a multi-hole flat extruded tube made of aluminum having a large number of holes therein, and the heat transfer fins 22 are formed.
The heat transfer partition 11 is a brazing sheet in which a brazing material is clad in advance on the front and back of an aluminum core material, and the heat transfer partition 11 An aluminum heat transfer fin 22 and a refrigerant passage member 16 of an aluminum perforated flat extruded tube are brought into contact with the inner and outer surfaces thereof and assembled.
Simultaneous brazing simultaneously allows thermal connection.

On the other hand, the refrigerant flowing through the inlet header pipe 17 has a large liquid phase,
Since the refrigerant flowing through the outlet header tube 188 receives heat, the gas phase increases, and the flow resistance of the refrigerant in the outlet header tube 18 becomes larger than in the inlet header tube 17. Therefore, the amount of the refrigerant flowing through each of the refrigerant passages 16 of the refrigerant passage member 15 flows more toward the refrigerant outlet pipe 20. Therefore, the flow rate of the refrigerant flowing through the refrigerant passage 16 at a position opposite to the refrigerant outlet pipe 20 is the smallest. When the amount of the refrigerant becomes smaller than a predetermined amount, the refrigerant is entirely vaporized (gasified) and a temperature rise due to sensible heat occurs. Therefore,
By mounting a temperature thermistor 24 as a temperature detecting means on the upper side of the refrigerant passage member 15 at a position opposite to the refrigerant outlet pipe 20, when the refrigerant leaks from the refrigerant circuit, etc. When the temperature of the thermistor 24 rises immediately when the refrigerant becomes insufficient and the refrigerant overheats,
By detecting this, the operation of the system can be normalized, the thermal decomposition and deterioration of the refrigerant can be prevented, and a highly reliable system can be obtained.

Further, the amount of the refrigerant flowing through each of the refrigerant passages 16 of the refrigerant passage member 15 flows more toward the refrigerant outlet pipe. Therefore, the refrigerant flowing through the refrigerant passage 16 at a position closer to the refrigerant outlet pipe 20 becomes the largest, and when the refrigerant in the refrigerant heater of the heating and cooling device runs out, the temperature rise finally occurs due to sensible heat. Therefore, when an abnormality occurs in the operation of controlling the temperature by the temperature detection or the output, and the refrigerant completely runs out of the refrigerant heater, the temperature-responsive temperature provided in the refrigerant passage member 15 at a position close to the refrigerant outlet pipe 20. The temperature of the switch 25 immediately rises and detects this to protect the device.

Further, the refrigerant inlet pipe 19 and the refrigerant outlet pipe 20 are attached to the header pipes 17 and 18 with the drawing direction being the same direction, so that the flow path of the refrigerant is at a position opposite to the refrigerant inlet pipe 19 and the refrigerant outlet pipe 20. When the refrigerant is overheated due to a decrease in the flow rate of the refrigerant due to an increase in the flow resistance, the temperature of the temperature thermistor 24 rises more quickly, and the temperature rise of the switch 25 is detected while detecting this. Is usually slower than the temperature thermistor 24 and last, resulting in a highly reliable system.

Further, by fixing the metal fitting 26 in close contact with the coolant passage member 15 by brazing, the heat of the coolant passage member 15 can be transferred to the temperature switch 25 through the metal fitting 26, and the responsiveness is improved. Furthermore, even when the refrigerant is slightly reduced, the refrigerant becomes gas in the refrigerant passage 16 above the refrigerant passage member 15 and absorbs heat with sensible heat to raise the temperature.Therefore, the temperature switch 26 is connected to the refrigerant outlet pipe 20 close to the refrigerant outlet pipe 20. This can be detected by being mounted above the refrigerant passage member 15 at the position, and a more reliable system can be obtained.

Further, when a large amount of oil accumulates in the refrigerant passage 16, the vaporization and circulation of the refrigerant are hindered due to its viscosity and low heat conduction. At this time, the circulation is obstructed in the same manner as when the refrigerant is reduced, so that the flow rate of the refrigerant flowing through the refrigerant passage 16 at the position opposite to the refrigerant outlet pipe 20 is minimized. (Gasification), the temperature rises due to sensible heat, and the temperature of the temperature thermistor 24 rises. By discharging oil from the oil drain pipe 21 connected to the inlet header pipe 17 by this detection output, uniform circulation of the refrigerant can be maintained, and thermal decomposition of the refrigerant due to local overheating does not occur, and a highly reliable system can be obtained. .

Effects of the Invention As described above, according to the heat exchanger of the present invention, the natural circulation cycle of the refrigerant heater heated by the burner or the like is smoothly performed by increasing the natural circulation force due to the rise of bubbles in the plurality of refrigerant passages. The refrigerant does not locally overheat, and ensures the unpowered heat transfer to be performed without causing thermal decomposition.

And by having the structure which provided the temperature detection means in the refrigerant | coolant passage member in the position on the opposite side to a refrigerant outlet pipe, when refrigerant | coolant overheats when refrigerant | coolant lacks in the refrigerant heater of a heating / cooling device, The temperature of the temperature detecting means can immediately detect this, normalize the operation of the system, and prevent the thermal decomposition and deterioration of the refrigerant.

At the same time, by providing a temperature-sensitive switch to the refrigerant passage member at a position closer to the refrigerant outlet pipe, the temperature switch is at a lower temperature than the normal temperature thermistor, and when the refrigerant heater runs out of refrigerant, Since a temperature rise due to sensible heat occurs in this location, if an abnormality occurs in the operation of controlling the temperature by detecting or outputting the temperature, a temperature-sensitive switch provided in the refrigerant passage member at a position close to the refrigerant outlet pipe. Can detect this and provide a highly reliable system that can maintain safety and protect equipment.

Also, by attaching the refrigerant inlet pipe and the refrigerant outlet pipe to the header pipe in the same direction, the temperature rise of the temperature switch is usually slower than that of the temperature thermistor, and a more reliable system can be obtained.

Also, by mounting the temperature switch on the upper part of the refrigerant passage member at a position near the refrigerant outlet pipe, even if the refrigerant is slightly reduced, the upper part of the refrigerant passage becomes gas, the refrigerant absorbs heat with sensible heat and the temperature rises , Which can be detected quickly and a more reliable system can be obtained.

[Brief description of the drawings]

1 is a partially cutaway perspective view of a heat exchanger showing one embodiment of the present invention, FIG. 2 is a sectional view of a passage member of the heat exchanger, FIG. 3 is a rear view of the heat exchanger, FIG. FIG. 4 is a circuit configuration diagram of a conventional refrigerant heating / heating machine, and FIG. 5 is a perspective view of a heat exchanger used in the conventional refrigerant heating / heating machine. 8 Burner, 10 Combustion chamber, 11 Heat transfer bulkhead, 12
High temperature gas passage member, 13 combustion gas inlet, 14 exhaust outlet, 15 refrigerant passage member, 16 refrigerant passage, 17 inlet header tube, 18 outlet header tube, 19 refrigerant inlet Pipe, 20: refrigerant outlet pipe, 24: temperature thermistor (temperature detecting means), 25: temperature switch.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F28D 1/00-13/00 F25B 41/00 F25B 49/02 510

Claims (4)

(57) [Claims] A hot gas passage member having a combustion gas inlet serving as a combustion chamber of a burner; a heat transfer partition having the hot gas passage member closely attached to an inner surface facing the combustion chamber; and an outer surface of the heat transfer partition. A refrigerant passage member integrally formed at a position corresponding to the high-temperature gas passage member and having a plurality of vertical refrigerant passages; header pipes provided at upper and lower ends of the refrigerant passage member; and each of the header pipes A refrigerant inlet tube and a refrigerant outlet tube attached to the refrigerant outlet member; a temperature detecting means provided in the refrigerant passage member at a position opposite to the refrigerant outlet tube; and a refrigerant passage member at a position close to the refrigerant outlet tube. And a temperature-sensitive switch provided in the heat exchanger. 2. The heat exchanger according to claim 1, wherein the refrigerant inlet tube and the refrigerant outlet tube are attached to the header tubes so as to extend in the same direction. 3. The heat exchanger according to claim 1, wherein the temperature-sensitive switch is mounted on an upper portion of the refrigerant passage member at a position near the refrigerant outlet pipe. 4. The heat exchanger according to claim 1, wherein the temperature-sensitive switch is mounted using iron fixed in close contact with the refrigerant passage member.