JPH051961U - Heat exchanger - Google Patents

Abstract

(57) [Summary] [Purpose] In the heat exchanger, the inner pipe through which a medium such as water flows is prevented from being destroyed by freezing. [Structure] A pipe is tightly fitted to the outer circumference of an inner pipe covered with a header for supplying a refrigerant into a heat exchanger to reinforce the pipe. [Effect] Prevent the inner tube of the heat exchanger from being destroyed by freezing,
It is possible to prevent damage to the refrigerant circuit.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a heat exchanger used in a chiller unit for cooling water or the like, in which water flowing in an inner pipe is heat-exchanged by a refrigerant flowing in an outer pipe.

[0002]

[Prior Art]

 FIG. 3 is a refrigerant circuit diagram of a conventional refrigeration system, in which 1 is a compressor that sucks refrigerant gas and discharges it as compressed cooling medium gas, 2 is an air side heat exchanger that serves as a condenser, and a motor 3 and a fan. It is forcedly air-cooled by the blower 5 consisting of 4. Reference numeral 6 is a throttle device for reducing the pressure of the condensed refrigerant, 7 is a water side heat exchanger that serves as an evaporator, and 8 is a suction accumulator that stores the liquid refrigerant and returns only the gas refrigerant to the compressor 1.

The water-side heat exchanger 7 is shown, for example, in the Sumitomo Light Metal Industry Co., Ltd. catalog (C-O-03O), FIG. 4 is an overall external perspective view, and FIG. 5 is V-V in FIG. 6 is a sectional view taken along line VI-VI in FIG. That is, the water-side heat exchanger 7 is composed of an inner pipe 7a and an outer pipe 7b, and an outer double pipe, in which a liquid medium such as water flows in the inner pipe 7a and a refrigerant in the outer pipe 7b. Flow through. Radial heat transfer fins 7j are provided on the inner wall of the outer pipe 7b, and a refrigerant passage 7h is defined by the inner pipe 7a. Reference numeral 7f is a header having an annular chamber 7i for evenly supplying the refrigerant to the refrigerant passage 7h, to which the refrigerant pipe 9 is connected. Reference numerals 7c and 7d denote inlet and outlet water connection ports connected to both ends of the inner pipe 7a, and 7e is a heat insulation box surrounding the water side heat exchanger 7, which is molded from a hard urethane foam.

Next, the operation will be described. The high-temperature and high-pressure gas refrigerant discharged by the compressor 1 is supplied to the condenser 2, and is forcibly air-cooled by the blower 5 and condensed to become a high-temperature and high-pressure liquid cooling medium. This liquid refrigerant enters the expansion device 6, where it is decompressed to become a low-temperature low-pressure gas-liquid mixed refrigerant, and flows from the refrigerant pipe 9 into the water-side heat exchanger 7. The gas-liquid mixed refrigerant exchanges heat with the water passing through the inner pipe 7a and the outer pipe 7b from the annular chamber 7i of the header 7f and the inner pipe 7a, and absorbs heat by cooling the water to be vaporized. The refrigerant that has not been completely vaporized in the water-side heat exchanger 7 remains in the suction accumulator 8, and the low-pressure refrigerant that has vaporized in the water-side heat exchanger 7 returns to the compressor 1 through the suction accumulator 8. The water that has exchanged heat in the inner pipe 7a circulates in the outer pipe connected to the water connection ports 7c and 7d and is supplied to the load.

[0005]

[Problems to be solved by the device]

 Since the conventional heat exchanger is configured as described above, when it is left outdoors with the refrigeration system stopped during cold weather such as winter, the heat exchange on the water side due to the decrease in outside air temperature The water retained in the external pipe connected to the container 7 and the water connection ports 7c and 7d is gradually frozen, and the volume expansion during freezing causes the inner pipe 7a, especially the outer pipe, to be radially arranged. The inner pipe portion covered with the header 7f which was not reinforced by the plurality of heat transfer fins 7j was sometimes broken, resulting in a serious failure. For this reason, several countermeasures have been taken in the past, and a method that is generally implemented is to automatically operate a water circulation pump when the outside air temperature drops, but freeze protection is provided due to forgetting to turn on the power or a power failure. There is a strong possibility that it will become impossible, and if water enters the refrigerant circuit due to freezing breakdown of the water side heat exchanger 7, it will be a fatal failure as a refrigeration system and the refrigeration system is being used. The system was seriously damaged.

The present invention has been made in order to solve the above problems, and provides a heat exchanger that does not break even if it freezes, because other protection functions do not operate. With the goal.

[0007]

[Means for Solving the Problems]

 The heat exchanger according to the present invention comprises an inner pipe through which a heat medium such as water flows, heat transfer fins inserted into the inner pipe and radially arranged on the inner wall of the pipe, and the inner pipe wall. An outer pipe that forms a plurality of refrigerant flow passages, and a header that has an annular chamber that is external to the inner pipe so as to cover the ends of the outer pipe and that has an annular chamber that communicates with the refrigerant flow passages inside. In this heat exchanger, a pipe is inserted around the inner pipe to reinforce the inner pipe portion covered with the header.

[0008]

[Action]

 In this invention, the outer circumference of the inner pipe covered with the header is reinforced with a pipe to prevent the destruction of the refrigerant circuit due to the expansion of the volume even if the water in the inner pipe of the header portion freezes. You can

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of the same portion of the heat exchanger according to the present invention as FIG. 5, and FIG. 2 is a sectional view taken along the line II-II of FIG. Since it is the same as, the description will be omitted. Reference numeral 10 denotes a pipe made of, for example, a copper pipe that is tightly fitted and inserted into the outer peripheral portion of the inner pipe 7a covered with the header 7f, and thereby reinforces the inner pipe 7a portion. The length of the pipe 10 is such that it reaches the entire inside of the annular chamber 7i of the header 7f, and one end of the pipe 10 is in contact with the end of the outer pipe 7d.

In the heat exchanger of the present invention configured as described above, normally, the water entering from the water connection port 7c on the inlet side flows through the inner pipe 7a and exchanges heat with the refrigerant in the outer pipe 7b. And is cooled, and cold water is supplied from the water connection port 7d on the outlet side to the load side. On the other hand, when the refrigeration system is left outdoors with the operation of the refrigeration unit stopped in cold weather such as winter, the outside temperature of the outside connected to the water side heat exchanger 7 and the water connection ports 7c and 7d is reduced due to the low outside temperature. The water staying in the pipe freezes, and the pressure in the inner pipe 7a rises due to the volume expansion at the time of freezing. However, the portion where the refrigerant flows outside the inner pipe 7a is reinforced by the pipe 10. Since it is not destroyed, the refrigerant circuit is not contaminated with water and the like, and therefore the refrigerant circuit is not damaged.

Since the length of the pipe 10 substantially reaches the entire inside of the annular chamber 7i of the header 7f, the function of a jig and tool for determining the position when the header 7f is assembled can be obtained and the number of assembling steps can be reduced. .

[0012]

[Effect of the device]

 As described above, according to the present invention, the inner pipe portion covered by the header of the heat exchanger is reinforced by the pipe, so that even if the heat exchanger is frozen, the inner pipe portion is not destroyed. Therefore, it is possible to prevent serious damage to the refrigerant circuit.

[Brief description of drawings]

FIG. 1 is a sectional view of a heat exchanger according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a refrigerant circuit diagram of a conventional refrigeration system.

FIG. 4 is an external perspective view of a conventional heat exchanger.

5 is an enlarged sectional view taken along line VV of FIG.

6 is a cross-sectional view taken along the line VI-VI of FIG.

[Explanation of symbols]

 7 Water Side Heat Exchanger 7a Inner Tube 7b Outer Tube 7c, 7d Connection Port 7f Header 7h Refrigerant Flow Pipe 7i Annular Chamber 7j Heat Transfer Fin 10 Pipe

Claims (1)

[Claims for utility model registration] [Claim 1] An inner tube through which a heat medium such as water flows, heat transfer fins inserted into the inner tube and radially arranged on the inner wall of the tube, and the inner tube. An outer tube forming a plurality of refrigerant passages defined by a wall, and an outer chamber that is covered with the inner tube so as to cover the end portion of the outer tube, and has an annular chamber that communicates with the refrigerant passage inside. A heat exchanger comprising a header having the heat exchanger, wherein a pipe is attached to the outer circumference of the inner pipe to reinforce the inner pipe portion covered with the header.