JP2007113841A - Heat pump type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a liquid-gas heat exchanger and to reduce costs in a heat pump type water heater. <P>SOLUTION: An outer diameter of a liquid-side main tube 70 of the liquid-gas heat exchanger 25 is made smaller than outer diameters of a liquid-side inlet tube 71 and a liquid-side outlet tube 72 connected with both ends of the liquid-side main tube, and an outer diameter of a gas-side main tube 73 is made smaller than outer diameters of a gas-side inlet tube 74 and a gas-side outlet tube 75 connected with both ends of the gas-side main tube. Thus the liquid-gas heat exchanger 25 can be miniaturized, and the costs can be reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat pump type hot water supply apparatus using a liquid gas heat exchanger.

  It has been provided that a liquid gas heat exchanger is used in the middle of the refrigeration cycle of a heat pump hot water supply apparatus. This liquid gas heat exchanger performs heat exchange between the high-pressure refrigerant that flows out of the water heat exchanger and flows into the decompression mechanism, and the low-pressure refrigerant that flows out of the air heat exchanger. By providing this liquid gas heat exchanger, the refrigerant from the water heat exchanger (gas cooler) is supercooled, and the refrigerant entering the compressor is heated to prevent wet compression of the compressor. I am doing so.

  FIG. 7 shows a simplified diagram of a heat pump type hot water supply apparatus using the liquid gas heat exchanger (see Patent Document 1). The heat pump type hot water supply apparatus includes a tank unit 2 having a hot water storage tank 1 and a heat pump unit 4 having a refrigeration cycle 3. The hot water storage tank 1 of the tank unit 2 is provided with a water supply port 5 on its bottom wall and a hot water outlet 6 on its upper wall. Tap water is supplied from the water supply port 5 to the hot water storage tank 1, and hot hot water is discharged from the hot water outlet 6. In addition, the hot water storage tank 1 has a water intake 7 at the bottom wall and a hot water inlet 8 at the top of the side wall (peripheral wall), and the water intake 7 and the hot water inlet 8 are connected by a circulation path 9. Has been. The circulation path 9 is provided with a water circulation pump 10 and a heat exchange path 11. That is, when the water circulation pump 10 is driven, unheated water in the hot water storage tank 1 flows out from the water intake 7 to the circulation path 9 and returns to the hot water storage tank 1 from the hot water inlet 8 through the heat exchange path 11. .

  Next, the refrigeration cycle 3 is configured by connecting a compressor 13, a water heat exchanger 14 that constitutes the heat exchange path 11, an electric expansion valve (decompression mechanism) 15, and an air heat exchanger 16 in this order. Has been. That is, the discharge port of the compressor 13 and the water heat exchanger 14 are connected by the refrigerant passage 17, the water heat exchanger 14 and the electric expansion valve 15 are connected by the refrigerant passages 18 and 36, and the electric expansion valve 15 And the air heat exchanger 16 are connected by a refrigerant passage 19, and the air heat exchanger 16 and the compressor 13 are connected by a refrigerant passage 37 and a refrigerant passage 21. And as a refrigerant | coolant, natural refrigerant | coolants, such as a carbon dioxide gas which uses a high voltage | pressure side by a supercritical pressure, are used, for example.

  The refrigeration cycle 3 includes a liquid gas heat exchanger 25 that cools the high-pressure refrigerant that has flowed out of the water heat exchanger 14. In this case, the liquid gas heat exchanger 25 includes a first passage 26 through which the high-pressure refrigerant flowing out from the water heat exchanger 14 passes, and a second passage 27 through which the low-pressure refrigerant flowing out from the air heat exchanger 16 passes. ing. Then, heat exchange is performed between the high-temperature and high-pressure refrigerant passing through the first passage 26 and the low-temperature and low-pressure refrigerant passing through the second passage 27.

  Next, the operation of the heat pump type hot water supply apparatus (water heater operation) will be described. The compressor 13 is driven and the water circulation pump 10 is driven (actuated). Then, stored water (hot water) flows out from the water intake 7 provided at the bottom of the hot water storage tank 1, and this flows through the heat exchange path 11 of the circulation path 9. Further, the refrigerant discharged from the compressor 13 returns to the compressor 13 via the water heat exchanger 14, the decompression mechanism 15, and the air heat exchanger 16 in order. Therefore, the water flowing through the heat exchange path 11 of the circulation path 9 is heated (boiling) by the water heat exchanger 14 that is a gas cooler, and returned to the upper part of the hot water storage tank 1 from the hot water inlet 8. Then, by continuously performing such an operation, hot hot water is stored in the hot water storage tank 1.

  By the way, in the heat pump unit 4, if there is no liquid gas heat exchanger 25, a cycle such as A in FIG. 8A is configured when the temperature of water entering the heat exchange path 11 is low. When the temperature of water entering the path 11 is high, the cycle is as shown in B of FIG. That is, there is a large refrigerant amount difference in the radiator that is the water heat exchanger 14 between the cycle A in FIG. 8A and the cycle B in FIG. 8A, and the temperature of water entering the heat exchange path 11 is high. If it rises, the enthalpy difference in the heat dissipation process will become narrow, and the hot water heating capacity and COP will decrease. On the other hand, when the liquid gas heat exchanger 25 is provided, the refrigerant amount difference on the high pressure side due to the change in the incoming water temperature is absorbed, and the density of the outlet refrigerant of the liquid gas heat exchanger 25 even when the incoming water temperature is high. Is large and forms a normal cycle as shown in FIG. 8B.

  As described above, in the heat pump hot water supply apparatus, liquid gas heat exchange is performed to exchange heat between the high-pressure refrigerant that flows out of the water heat exchanger 14 and flows into the decompression mechanism 15 and the low-pressure refrigerant that flows out of the air heat exchanger 16. Since the unit 25 is provided, supercooling can be given to the refrigerant from the water heat exchanger (gas cooler) 14 and the refrigerant entering the compressor 13 can be heated. For this reason, wet compression of the compressor 13 can be prevented, and stable operation is possible.

Japanese Patent Application No. 2003-432416

  By the way, the liquid gas heat exchanger 25 includes a pipe-shaped first passage 26 through which the high-pressure refrigerant from the water heat exchanger 14 flows and a pipe provided in parallel with the first passage 26 as described above. And a second passage 27 having a shape. The first passage 26 of the liquid gas heat exchanger 25 includes a liquid side main pipe and a liquid side inlet pipe and a liquid side outlet pipe connected to both ends of the liquid side main pipe. The two passages 27 are composed of a gas side main pipe and a gas side inlet pipe and a gas side outlet pipe connected to both ends of the gas side main pipe. The outer diameter of the liquid side main pipe and the gas side main pipe of the conventional liquid gas heat exchanger 25 is the same as the liquid side inlet pipe, the liquid side outlet pipe, the gas side inlet pipe, and the gas side outlet pipe at both ends, or has a large diameter. Was used. For this reason, the liquid gas heat exchanger 25 itself is increased in size, and the cost is high.

  The present invention has been provided in view of the above-mentioned problems, and provides a heat pump type hot water supply apparatus for the purpose of making the liquid gas heat exchanger compact and reducing the cost.

  Therefore, the heat pump hot water supply apparatus according to claim 1 of the present invention includes the heat pump unit 4 in which the compressor 13, the water heat exchanger 14, the decompression mechanism 15, and the air heat exchanger 16 are sequentially connected, and the water heat A boiling operation for supplying unheated water to the heat exchange path 11 constituted by the exchanger 14 to heat the unheated water is enabled, and the water is discharged from the water heat exchanger 14 and flows into the pressure reducing mechanism 15. In the heat pump type hot water supply apparatus provided with the liquid gas heat exchanger 25 for performing heat exchange between the high pressure refrigerant and the low pressure refrigerant flowing out from the air heat exchanger 16, the liquid gas heat exchanger 25 has a pipe-shaped first. The passage 26 and the pipe-like second passage 27 are provided side by side, and the main pipes 70 and 72 in the passages 26 and 27 are respectively connected to the inlet pipes 71 and 74 and the outlets respectively connected to both ends thereof. Tubes 72, 75 It is characterized in that it is a remote small diameter.

  The heat pump type hot water supply apparatus according to claim 2 is characterized in that a substantially central portion of the liquid gas heat exchanger (25) is bent into a hairpin shape.

  According to the heat pump type hot water supply apparatus of the first aspect of the present invention, since each main pipe has a smaller diameter than each inlet pipe and each outlet pipe, the liquid gas heat exchanger can be made compact and the cost can be reduced. be able to. Furthermore, since each main pipe has a small diameter, it becomes easy to bend, and the assembly work efficiency can be improved.

  According to the heat pump type hot water supply apparatus according to claim 2, since the liquid gas heat exchanger is bent in a hairpin shape at a substantially central portion, a plurality of pipe-like liquid gas heat exchangers are used. The distance of the liquid gas heat exchanger itself can be increased, so that the effective length necessary for heat exchange between the high-pressure refrigerant and the low-pressure refrigerant can be obtained in a compact manner.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, this invention has the characteristics in the arrangement structure of the liquid gas heat exchanger 25, and the piping structure of a heat pump type hot-water supply apparatus is the same as that of the case of FIG.

  FIG. 1 is an exploded perspective view of a heat pump unit 4 showing only main components, and a machine room in which a compressor 13 and the like are arranged on one side of a partition plate 41 erected on the upper surface of a metal bottom plate 40. 42, and the other side of the partition plate 41 is a fan chamber 43 in which the air heat exchanger 16, the fan 22, and the like are arranged. Further, a front plate 45 integrated with a top plate 44 is disposed on the front side of the fan 22, and a bell mouth 46 is fixed to the inner surface side of the substantially lattice-shaped front plate 45 with screws 47. . When the fan 22 is driven to rotate, air is blown out through the front opening 45 and the circular opening 48 of the bell mouth 46, and the air passes through the air heat exchanger 16 so that the air heat is The exchanger 16 is cooled.

  FIG. 2 is an exploded perspective view of the air heat exchanger 16 as seen from the back side, and FIG. The air heat exchanger 16 is formed in a substantially L shape, and a support plate 51 for supporting and fixing the air heat exchanger 16 is also formed in a substantially L shape, and the air heat exchanger 16 is formed on the upper surface of the support plate 51. Is supported and fixed. The lower portion of the support plate 51 is located inside the flange 52 rising from the edge of the bottom plate 40, and the support plate 51 is disposed on the bottom plate 40 side. As shown in FIG. 3, the air heat exchanger 16 is positioned and fixed on the upper surface of the pedestal portion 54 formed on the upper surface of the upper piece 53 of the support plate 51.

  Further, as shown in FIG. 3, the water heat exchanger 14 is disposed at a position (a position below the air heat exchanger 16) located on the upper surface of the bottom plate 40 and in the fan chamber 43. The exchanger 14 has an outer shell made of a heat insulating material 55, and a water heat exchanger member 56 having a pipe-like and double structure is laminated inside the heat insulating material 55 in the vertical direction. The upper part of the water heat exchanger member 56 is piped so that the high-temperature refrigerant flows, and the lower part of the water heat exchanger member 56 is piped so that the low-temperature refrigerant flows.

  Next, the configuration and arrangement position of the liquid gas heat exchanger 25 will be described. As shown in FIG. 4, the liquid gas heat exchanger 25 includes a pipe-like first passage 26 through which high-temperature refrigerant from the water heat exchanger 14 flows, and a pipe-like shape having a diameter larger than the diameter of the first passage 26. And the second passage 27. The first passage 26 and the second passage 27 are arranged in parallel in the longitudinal direction, and both the passages 26 and 27 are fixed by brazing. The folded portion 60 at the substantially central portion of the liquid gas heat exchanger 25 is substantially U-shaped and bent into a hairpin shape, and is bent so that both the passages 26 and 27 are positioned in the vertical direction. Further, the liquid gas heat exchanger 25 is bent at approximately 90 ° at a bent portion 61 in the middle of the liquid gas heat exchanger 25 so as to be disposed around the water heat exchanger 14.

  The first passage 26 of the liquid gas heat exchanger 25 is connected to the liquid side main pipe 70, the liquid side inlet pipe 71 connected to one of the liquid side main pipes 70, and the other of the liquid side main pipe 70. And a liquid outlet pipe 72. Further, the second passage 27 includes a gas side main pipe 73, a gas side inlet pipe 74 connected to one of the gas side main pipe 73, and a gas side outlet pipe 75 connected to the other of the gas side main pipe 73. It consists of The outer diameter of the liquid side main pipe 70 of the first passage 26 is smaller than the outer diameters of the liquid side inlet pipe 71 and the liquid side outlet pipe 72 connected to both ends. The outer diameter of the gas side main pipe 73 of the second passage 27 is smaller than the outer diameters of the gas side inlet pipe 74 and the gas side outlet pipe 75 connected to both ends. In the description above and below, the liquid means a high-pressure refrigerant, and the gas means a low-pressure refrigerant.

  Further, the end of one liquid side inlet pipe 71 of the first passage 26 of the liquid gas heat exchanger 25 is used as a liquid side inlet portion 62 into which liquid flows, and the end of the other liquid side outlet pipe 72 of the first passage 26 is used. This portion is a liquid side outlet portion 63 from which the liquid flows out. Further, the end of one gas side inlet pipe 74 of the second passage 27 is used as a gas side inlet section 64 into which gas flows, and the gas from which gas flows out of the end of the other gas side outlet pipe 75 of the second passage 27. A side outlet 65 is provided. That is, the direction in which the liquid in the first passage 26 of the liquid gas heat exchanger 25 flows is opposite to the direction in which the liquid in the second passage 27 flows.

  FIG. 5 shows a simplified diagram of the heat pump unit 4, in which the refrigerant passage 18 is connected to the liquid side inlet portion 62 of the liquid side inlet pipe 71 of the first passage 26 of the liquid gas heat exchanger 25, and the refrigerant passage 36 is liquid. The liquid outlet portion 63 of the side outlet pipe 72 is connected. The refrigerant passage 37 is connected to the gas side inlet portion 64 of the gas side inlet pipe 74 of the second passage 27 of the liquid gas heat exchanger 25, and the refrigerant passage 21 is connected to the gas side outlet portion 65 of the gas side outlet pipe 75. Is done.

  FIG. 6 shows a schematic configuration diagram of the liquid gas heat exchanger 25. As described above, the diameter of the liquid side main pipe 70 constituting the first passage 26 of the liquid gas heat exchanger 25 is set at both ends. The diameter is smaller than the diameter of the liquid side inlet pipe 71 and the liquid side outlet pipe 72. The diameter of the gas side main pipe 73 constituting the second passage 27 is smaller than the diameters of the gas side inlet pipe 74 and the gas side outlet pipe 75 at both ends. Here, when the outer diameter of the liquid side main pipe 70 is, for example, 3.2 to 3.3 mm (thickness: 0.5 mm), the outer diameters of the liquid side inlet pipe 71 and the liquid side outlet pipe 72 are both 4 mm ( (Wall thickness: 0.5 mm). Further, when the outer diameter of the gas side main pipe 73 is, for example, 6.4 to 8 mm (thickness: 0.8 to 1.0 mm), the outer diameters of the gas side inlet pipe 74 and the gas side outlet pipe 75 are both It is 9.5 mm (wall thickness: 0.8 to 1.2 mm).

  As shown in FIGS. 2 and 4, the liquid gas heat exchanger 25 configured as described above with the pair of pipe-like first passages 26 and second passages 27 is substantially L-shaped. The liquid gas heat exchanger 25 formed in a substantially L shape is arranged so as to surround the periphery of the water heat exchanger 14. Further, when the liquid gas heat exchanger 25 is disposed from the back surface to the side surface of the water heat exchanger 14 as described above, the liquid gas heat exchanger 25 is disposed below the air heat exchanger 16 as shown in FIG. It is in the state.

  That is, the air heat exchanger 16 is formed in a substantially L shape as shown in FIG. 2, and the liquid gas heat exchanger 25 is also formed in a substantially L shape so as to correspond to the shape of the substantially L shape. The size of the liquid gas heat exchanger 25 is approximately the same size as the air heat exchanger 16. Thereby, the liquid gas heat exchanger 25 can be arrange | positioned in the position below the air heat exchanger 16, and as shown in FIG. 3, with the upper piece 53 of the support plate 51 as a boundary, the air heat exchanger 16 is on the upper side. Is arranged, and the liquid gas heat exchanger 25 is arranged below the upper piece 53. Moreover, the liquid gas heat exchanger 25 will be arrange | positioned in the space 67 formed between the inner surface of the support plate 51, and the water heat exchanger 14, and the space 67 is utilized effectively.

  In addition, the liquid gas heat exchanger 25 configured by bringing the pair of pipe-shaped first passage 26 and the second passage 27 into contact with each other in parallel in the longitudinal direction is bent in a hairpin shape at the folded portion 60 in the substantially central portion, Since it is bent into a substantially L shape over the back side and the side of the water heat exchanger 14 so as to correspond to the substantially L shape of the air heat exchanger 16, it is necessary to perform heat exchange between the gas and the liquid. Effective length can be obtained in a compact manner. In addition, since the liquid gas heat exchanger 25 is arranged below the air heat exchanger 16, the wind from the fan 22 does not hit the liquid gas heat exchanger 25. Heat dissipation loss can be reduced.

  Thus, in this embodiment, the outer diameter of the liquid side main pipe 70 of the liquid gas heat exchanger 25 is smaller than the outer diameters of the liquid side inlet pipe 71 and the liquid side outlet pipe 72 connected to both ends, and the gas Since the outer diameter of the side main pipe 73 is smaller than the outer diameters of the gas side inlet pipe 74 and the gas side outlet pipe 75 connected to both ends, the liquid gas heat exchanger 25 can be made compact and the cost can be reduced. Can be planned. Furthermore, since the liquid side main pipe 70 and the gas side main pipe 73 have a small diameter, it is easy to bend, and the assembly work efficiency can be improved.

It is a principal part disassembled perspective view of the heat pump unit in embodiment of this invention. It is a disassembled perspective view which shows the arrangement | positioning state of the air heat exchanger and liquid gas heat exchanger in embodiment of this invention. It is a principal part expanded sectional view of the air heat exchanger and liquid gas heat exchanger in embodiment of this invention. (A) (b) is the top view and front view of a liquid-gas heat exchanger in embodiment of this invention. It is a piping simplified figure of the heat pump unit in an embodiment of the invention. It is a schematic block diagram of the liquid gas heat exchanger in embodiment of this invention. It is a piping simplification figure of a heat pump type hot-water supply apparatus. The comparison between when the incoming water temperature is low and when it is high is shown, (a) is a graph when there is no liquid gas heat exchanger, and (b) is when there is a liquid gas heat exchanger. FIG.

Explanation of symbols

4 Heat Pump Unit 11 Heat Exchange Path 14 Water Heat Exchanger 15 Depressurization Mechanism 16 Air Heat Exchanger 25 Liquid Gas Heat Exchanger 26 First Passage 27 Second Passage 70 Liquid Side Main Pipe 71 Liquid Side Inlet Pipe 72 Liquid Side Outlet Pipe 73 Gas Side main pipe 74 Gas side inlet pipe 75 Gas side outlet pipe

Claims (2)

  A heat pump unit (4) in which a compressor (13), a water heat exchanger (14), a pressure reducing mechanism (15), and an air heat exchanger (16) are sequentially connected is provided, and the water heat exchanger (14) A heating operation in which unheated water is supplied to the configured heat exchange path (11) to heat the unheated water is enabled, and flows out from the water heat exchanger (14) into the pressure reducing mechanism (15). In the heat pump hot water supply apparatus provided with the liquid gas heat exchanger (25) for exchanging heat between the high pressure refrigerant to be exchanged with the low pressure refrigerant flowing out from the air heat exchanger (16), the liquid gas heat exchanger (25) The pipe-shaped first passage (26) and the pipe-shaped second passage (27) are provided side by side, and the main pipes (70), (72) in the passages (26), (27) are Each inlet pipe (71) (74) and each outlet connected to both ends Tube (72) (75) a heat pump type hot water supply apparatus characterized by being smaller in diameter than.   The heat pump type hot water supply apparatus according to claim 1, wherein the liquid gas heat exchanger (25) has a substantially central portion bent into a hairpin shape.