JP4244038B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a heat pump type water heater, and more particularly to a heat exchanger that recovers heat radiation from a compressor.

Some heat pump hot water heaters are provided with a compressor shell heat exchanger and heated from the compressor shell to produce hot water (see, for example, Patent Documents 1 and 2).
Japanese Patent Laid-Open No. 58-80438 JP 2002-372318 A

  In the heat pump type hot water heater, when the temperature of the compressor rises greatly, the operation of the compressor is stopped to protect the electric motor winding by using a temperature sensor or the like, but this protection operation is started. Until the temperature of the compressor drops below a predetermined temperature, the compressor cannot be operated, and thus there is a problem that the heating capacity is insufficient.

  Moreover, the heat release from the compressor has a problem of reducing efficiency because the heat source having the highest temperature is discarded for the heat pump hot water heater.

  Patent Document 1 and Patent Document 2 have been made to solve the above problems, but if a heat exchanger is arranged around the compressor, the air venting work at the time of heat pump water heater installation work is insufficient. There is a problem that problems such as boiling-up abnormality occur.

  In addition, when a heat exchanger is provided around the compressor, the contact between the compressor and the heat exchanger is inadequate, so the heat transfer performance from the compressor to water is reduced, and a sufficient effect is obtained. There was a problem that it was difficult.

  Further, when a heat exchanger is provided around the compressor, there are problems that the heat exchanger main body and the connected pipe are fatigued due to the vibration of the compressor, or water leakage due to electrolytic corrosion occurs.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a heat pump water heater having high efficiency and low cost while improving reliability.

  The heat pump type hot water heater according to the present invention comprises a refrigerant circuit in which a compressor, a gas cooler, a throttle and an evaporator are connected in an annular shape, and the valve opening of the throttle can be electrically adjusted, and a hot water supply liquid passes through a water circulation pump. A water circuit that is supplied to the hot water tank through a compressor shell heat exchanger that has a flat cross section and is in surface contact with the compressor surface and that has a heat exchange portion in contact with the compressor after passing through the gas cooler. The water inlet pipe side of the compressor shell heat exchanger is the lower part and the water outlet pipe side is the upper part.

The heat pump type hot water heater according to the present invention has the above-described configuration, which facilitates the air venting operation when installing the heat pump type hot water heater, and eliminates stagnant air in the water circuit. There is.
The large contact area between the compressor and the compressor shell heat exchanger reduces heat loss from the compressor and improves efficiency by recovering heat to the user side, while suppressing the winding temperature of the compressor motor. Therefore, there is an effect of improving reliability.

Embodiment 1 FIG.
1 to 9 are diagrams showing the first embodiment, FIG. 1 is a refrigerant and water circuit diagram, FIG. 2 is a perspective view of a heat pump type water heater unit, and FIG. 3 is a comparison of the characteristics of a chlorofluorocarbon refrigerant and a natural refrigerant. 4 is a longitudinal sectional view of the rotary compressor, FIG. 5 is a flowchart at the time of defrost operation, FIG. 6 is a diagram showing an assembly outline of the compressor and the compressor shell heat exchanger, and FIG. 7 is a compressor shell heat exchanger. FIG. 8 is a sectional view of a member in contact with the compressor of the compressor shell heat exchanger, and FIG. 9 is a sectional view of another example of a member in contact with the compressor of the compressor shell heat exchanger.

  As shown in the figure, the refrigerant circuit 5 is configured by sequentially connecting a high-pressure compressor 1, a gas cooler 2, a throttle 3, and an evaporator 4 inside the shell. A discharge gas temperature detection sensor 24 for detecting the discharge gas temperature is attached to the discharge refrigerant pipe 14 of the compressor 1.

  The water circuit 9 includes a water circulation pump 7, a compressor shell heat exchanger 8, and an air vent circuit 10.

  The water heater unit has the configuration shown in FIG. 2, and a gas cooler 2 is disposed below the compressor 1. A blower 25 is provided next to the compressor 1 via a partition, and cools the evaporator 4 surrounding the blower 25. A water circulation pump 7 is placed beside the gas cooler 2.

As the refrigerant in the refrigerant circuit 5 shown in FIG. 1, a CO ₂ refrigerant having a low critical temperature (the critical temperature is 31 ° C.) is used. As shown in FIG. 3, the CO ₂ refrigerant has a global warming potential (GWP) and an ozone depletion coefficient (ODP) smaller than those of the chlorofluorocarbon refrigerant. Since CO ₂ is used as a refrigerant, boiling can be efficiently performed at a high temperature (90 ° C. or higher), and at the same time, there is an effect of contributing to prevention of global warming.

  As shown in FIG. 4, the compressor 1 is, for example, a rotary compressor having a high pressure inside the shell, and an electric element portion 1 a, a compression element portion 1 b and the like are accommodated in the compressor shell 11. The low-pressure refrigerant discharged from the evaporator 4 enters the suction muffler 12 through the suction refrigerant pipe 13, the refrigerant gas is sucked into the compression element portion 1 b and compressed there, and the high-pressure refrigerant gas is discharged into the compressor shell 11. Is done. Furthermore, it flows from the discharge refrigerant pipe 14 to the gas cooler 2.

  In the refrigerant circuit shown in FIG. 1, the compressor 1 compresses and discharges the refrigerant sucked from the suction muffler 12 to a critical pressure or higher under general use conditions. The gas cooler 2 exchanges heat between the high-pressure gas refrigerant discharged from the compressor 1 and hot water supply water. The throttle 3 is a device that depressurizes the refrigerant flowing out of the gas cooler 2 according to the valve opening, and is electrically controlled by a control device (not shown). The evaporator 4 evaporates the refrigerant decompressed by the throttle 3 by heat exchange with the outside air blown by the blower 25.

  The water circulation pump 7 is connected to a hot water storage tank (not shown), passes the gas cooler 2 from the bottom of the hot water storage tank, and then circulates water toward the top of the hot water storage tank through the compressor shell heat exchanger 8. . An air vent circuit 10 is attached to the water outlet pipe 20 of the compressor shell heat exchanger 8.

  When the surface of the evaporator 4 is frosted in winter, the valve opening of the throttle 3 is increased to perform the defrost operation. Usually, the water circulation pump 7 is stopped to prevent the boiling water temperature from decreasing. However, when the discharge gas temperature detection sensor 24 detects that the discharge temperature of the compressor 1 is 100 ° C. or higher, bumping occurs in the heat exchange portion 15 in contact with the compressor, and the compressor shell heat exchanger 8 is destroyed. In order to prevent this, the pump is operated intermittently (see FIG. 5).

  As shown in FIG. 6, a compressor shell heat exchanger 8 is attached around the compressor shell 11. A water inlet header 16 and a water outlet header 18 are connected to a heat exchanging portion 15 in contact with the compressor of the compressor shell heat exchanger 8, and a water inlet pipe 19 and a water outlet header 18 are provided below the water inlet header 16. A water outlet pipe 20 is connected to the upper part. An air vent circuit 10 is connected to the water outlet pipe 20.

  Since the water inlet pipe 19 of the heat exchanger composed of the heat exchanging portion 15 in contact with the compressor is the lower part and the water outlet pipe 20 is the upper part, the air venting work at the time of the heat pump hot water heater installation work becomes easy, and the water circuit Since there is no accumulated air in the interior, there is an effect that it is possible to prevent the occurrence of boiling abnormalities.

  Since the air vent circuit 10 (air vent pipe and stopper) is connected to the water outlet pipe 20 of the heat exchanger that is composed of the heat exchanging portion 15 in contact with the compressor, the air venting work at the time of the heat pump hot water supply installation work is easy. Thus, the stagnant air in the water circuit is eliminated, so that it is possible to prevent the occurrence of abnormal boiling and the like.

FIG. 7 is a production diagram of the compressor shell heat exchanger 8, and the heat exchange portion 15 in contact with the compressor has a circumferential angle θ ≧ 180 ° of the compressor.
Since the heat exchanger constituted by the heat exchange portion 15 in contact with the cylindrical compressor and in contact with the compressor is in contact with the circumference of the compressor shell 11 by 180 degrees or more, the compressor 1 and the compressor shell heat exchange. Since the contact area of the compressor 8 is large, the heat loss from the compressor 1 can be reduced, and the efficiency can be improved by recovering heat to the use side, and the winding temperature of the electric element portion 1a of the compressor 1 can be suppressed. There is an effect of improving reliability.

  FIG. 8 shows a cross section of the heat exchange portion 15 in contact with the compressor. Since the cross-section is a flat tube shape and the flat portion is in surface contact with the compressor shell 11, the contact area between the compressor 1 and the compressor shell heat exchanger 8 is large, so that heat loss from the compressor 1 is reduced. The efficiency can be improved by recovering heat to the use side, and the winding temperature of the electric element portion 1a of the compressor 1 can be suppressed, so that the reliability is improved.

  The cross section of the compressor shell heat exchanger 8 is preferably a flat portion on the side in contact with the compressor shell 11, but the outer surface may not be a flat surface, for example, a semicircular shape as shown in FIG. .

  Since the contact member of the heat exchanger configured by the heat exchanging portion 15 in contact with the compressor is connected to the water inlet header 16 and the water outlet header 18, the manufacturing cost can be reduced.

Embodiment 2. FIG.
10 and 11 are diagrams showing the second embodiment, FIG. 10 is a diagram showing an example of the configuration of the compressor shell heat exchanger 8, and FIG. 11 is another example of the configuration of the compressor shell heat exchanger 8. FIG.
In contrast to the first embodiment, the header is divided into a plurality of parts, and a heat exchange portion 15 that is in contact with the compressor is connected via a water intermediate header 17.

  In the heat pump type water heater configured as described above, the temperature efficiency is improved because the length of the water flow path of the compressor shell heat exchanger 8 is increased. Moreover, since the flow velocity of the water which flows through the heat exchange part 15 which contacts a compressor increases, a heat transfer rate improves. For this reason, the heat dissipation loss reduction effect from the compressor 1 is large, and efficiency can be improved by recovering heat to the use side, and reliability can be improved because the winding temperature of the electric element portion 1a of the compressor 1 can be suppressed. effective.

Embodiment 3 FIG.
12 and 13 are diagrams showing Embodiment 3, FIG. 12 is a refrigerant and water circuit diagram, and FIG. 13 is a flowchart at the time of defrosting operation.
In the refrigerant circuit shown in FIG. 12, the difference from Embodiment 1 is a defrost system, which is a hot gas bypass circuit. The defrosting operation is performed by opening the hot gas bypass valve 6.

  When the surface of the evaporator 4 is frosted in winter, the hot gas bypass valve 6 of the hot gas bypass circuit is opened and the defrost operation is performed, but normally the water circulation pump 7 is stopped to prevent the boiling water temperature from decreasing. To do. However, when the discharge gas temperature detection sensor 24 detects that the discharge temperature of the compressor 1 is 100 ° C. or higher, bumping occurs in the heat exchange portion 15 in contact with the compressor, and the compressor shell heat exchanger 8 is destroyed. In order to prevent this, the pump is operated intermittently (see FIG. 13).

Embodiment 4 FIG.
FIGS. 14 and 15 are diagrams showing Embodiment 4, FIG. 14 is a diagram showing an assembly outline of a compressor and a jacket type compressor shell heat exchanger, and FIG. 15 is a diagram showing a compressor shell heat exchanger. .

  As shown in FIG. 14, a thin resin sheet 21 is sandwiched between the compressor 1 and the compressor shell heat exchanger 8, and a heat insulating member (not shown) is wound around the outside of the compressor shell heat exchanger 8. Tighten with a band from the outside and fix. The thin resin sheet 21 eliminates the gap caused by the deformation of the compressor shell heat exchanger 8 and the difference in the thermal expansion coefficient between the compressor 1 and the compressor shell heat exchanger 8, thereby preventing an increase in contact thermal resistance, thereby improving the performance. There is. In addition, the compressor shell heat exchanger 8 can be prevented from being damaged by spatter deposits during assembly of the compressor and from being damaged by electric corrosion, thereby improving the reliability. Furthermore, there is an effect that the assemblability is improved as compared with the paste application.

  The compressor shell heat exchanger 8 has a configuration in which the jacket type is divided into two in the circumferential direction, and the jackets are connected by a connection pipe 23 and connected to a water inlet pipe 19, a water outlet pipe 20, the gas cooler 2, a valve, and the like. Consists of resin piping (silicon tube with high heat resistance, etc.).

Since the heat exchange part 15 in contact with the compressor has a structure in which the jacket type is divided into two parts, there is no need to change the manufacturing process of the compressor, and it is possible to prevent interference with the suction muffler 12 and improve the assemblability.
In addition, the jackets are connected by connecting pipes 23, and the water inlet pipe 19, the water outlet pipe 20, the gas cooler 2, and the connection part to the valve, etc. are made of resin pipes, so that damage to the pipes due to vibration of the compressor 1 is prevented. In addition, the piping can be easily routed.

  The jacket-type compressor shell heat exchanger 8 having the same effect as that of a resin formed by insert molding a copper plate on the inner surface side has the effect of reducing the weight and cost.

  The water inlet pipe 19, the water outlet pipe 20 and the connection pipe 23 connecting the jacket of the jacket type compressor shell heat exchanger 8 shown in FIG. The flow path forming member 22 arranged so as to meander is disposed.

  With the above configuration, the effective heat transfer area can be increased, the performance is improved, and the strength against water pressure is improved and improved by the flow path forming member.

Embodiment 5 FIG.
FIG. 16 is a diagram showing the fifth embodiment, and the compressor shell heat exchanger 8 is a form in which a water pipe is wound around the compressor shell 11. The inlet of the water pipe is located at the bottom and the outlet of the water pipe is located at the top.

  According to the above configuration, as in the first embodiment, the air venting operation at the time of the heat pump type hot water heater installation work is facilitated, and there is no stagnant air in the water circuit, so that it is possible to prevent the occurrence of abnormal boiling and the like.

Embodiment 6 FIG.
FIG. 17 is a diagram showing the sixth embodiment, and the compressor shell heat exchanger 8 is a form in which the compressor shell 11 is doubled. The inlet of the water pipe is located at the bottom and the outlet of the water pipe is located at the top.

  According to the above configuration, as in the first embodiment, the air venting operation at the time of the heat pump type hot water heater installation work is facilitated, and there is no stagnant air in the water circuit, so that it is possible to prevent the occurrence of abnormal boiling and the like.

It is a figure which shows Embodiment 1, and is a refrigerant | coolant and a water circuit diagram. It is a figure which shows Embodiment 1, and is a perspective view of a heat pump type water heater unit. It is a figure which shows Embodiment 1, and is the figure which compared the characteristic of the fluorocarbon refrigerant | coolant and the natural refrigerant | coolant. FIG. 3 is a diagram illustrating the first embodiment, and is a longitudinal sectional view of a rotary compressor. It is a figure which shows Embodiment 1, and is a flowchart figure at the time of a defrost driving | operation. It is a figure which shows Embodiment 1, and is a figure which shows the assembly outline | summary of a compressor and a compressor shell heat exchanger. It is a figure which shows Embodiment 1, and is a figure which shows a compressor shell heat exchanger. It is a figure which shows Embodiment 1, and is sectional drawing of the member which contact | connects the compressor of a compressor shell heat exchanger. It is a figure which shows Embodiment 1, and is sectional drawing which shows the other example of the member which contacts the compressor of a compressor shell heat exchanger. It is a figure which shows Embodiment 2, and is a figure which shows an example of a structure of a compressor shell heat exchanger. It is a figure which shows Embodiment 2, and is a figure which shows the other example of a structure of a compressor shell heat exchanger. It is a figure which shows Embodiment 3, and is a refrigerant | coolant and a water circuit diagram. It is a figure which shows Embodiment 3, and is a flowchart figure at the time of a defrost driving | operation. It is a figure which shows Embodiment 4, and is a figure which shows the assembly outline | summary of a compressor and a jacket type compressor shell heat exchanger. It is a figure which shows Embodiment 4, and is a figure which shows a compressor shell heat exchanger. It is a figure which shows Embodiment 5, and is a figure which shows the compressor shell heat exchanger which wound water piping around the compressor shell. It is a figure which shows Embodiment 6, and is a figure which shows the compressor shell heat exchanger which comprised the compressor shell twice.

Explanation of symbols

  1 compressor, 2 gas cooler, 3 throttle, 4 evaporator, 5 refrigerant circuit, 6 hot gas bypass valve, 7 water circulation pump, 8 compressor shell heat exchanger, 9 water circuit, 10 air vent circuit, 11 compressor shell, 12 Suction muffler, 13 Suction refrigerant piping, 14 Discharge refrigerant piping, 15 Heat exchange part in contact with compressor, 16 Water inlet header, 17 Water intermediate header, 18 Water outlet header, 19 Water inlet piping, 20 Water outlet piping, 21 Thin resin Sheet, 22 flow path forming member, 23 connecting pipe, 24 discharge gas temperature detection sensor, 25 blower.

Claims (8)

A refrigerant capable of electrically adjusting the valve opening of the throttle by connecting an electric element part having a winding inside the compressor shell and a compressor in which the compression element part is housed, a gas cooler, a throttle and an evaporator connected in an annular shape Circuit,
After the hot water supply liquid has passed through the gas cooler via a water circulation pump, the cross section is flat and heat exchange is performed in contact with the compressor at a heat exchange portion in surface contact with the compressor surface. A water circuit supplied to the hot water tank through a compressor shell heat exchanger that suppresses the winding temperature,
The compressor shell heat exchanger is connected to a water inlet header at a lower part of the heat exchange part, the heat exchange part is connected via a plurality of water intermediate headers, and is connected to a water outlet header at an upper part of the heat exchange part. A heat pump water heater characterized by being connected. A refrigerant capable of electrically adjusting the valve opening of the throttle by connecting an electric element part having a winding inside the compressor shell and a compressor in which the compression element part is housed, a gas cooler, a throttle and an evaporator connected in an annular shape Circuit,
After the hot water supply liquid has passed through the gas cooler via a water circulation pump, the cross section is flat and heat exchange is performed in contact with the compressor at a heat exchange portion in surface contact with the compressor surface. A water circuit supplied to the hot water tank through a compressor shell heat exchanger that suppresses the winding temperature,
With the water inlet pipe side of the compressor shell heat exchanger as the lower part and the water outlet pipe side as the upper part,
A thin resin sheet is sandwiched between the compressor and the compressor shell heat exchanger, and a heat insulating member is wound around the outside of the heat exchanger, and is fastened and fixed with a band or the like from the outside. Heat pump water heater. The compressor is disposed in the upper than the gas cooler, according to claim 1 or claim, characterized in that pipes and plug for air vent is connected to a water outlet pipe of the compressor shell heat exchanger 2. A heat pump type water heater according to 2 . In the external shape of the compressor cylindrical shape, the compressor shell heat exchanger, any one of claims 1 to 3, characterized in that in contact more than 180 degrees in a circumferential portion of the compressor surface heat pump water heater according to. The heat pump type hot water supply according to any one of claims 2 to 4 , wherein a heat exchange portion of the compressor shell heat exchanger that contacts the compressor is connected to a water inlet header and a water outlet header. Machine. The compressor shell heat exchanger is connected to a water inlet header at a lower part of the heat exchange part, the heat exchange part is connected via a plurality of water intermediate headers, and is connected to a water outlet header at an upper part of the heat exchange part. It is connected, The heat pump type hot water heater as described in any one of Claims 2 thru | or 5 characterized by the above-mentioned. The heat pump type hot water heater according to any one of claims 1 to 6 , wherein the water circulation pump is operated intermittently when the discharge temperature of the compressor is 100 ° C or higher during the defrost operation. Heat pump water heater according to any one of claims 1, wherein to 7 the CO _2, characterized in that the refrigerant.

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