JP2008202826A - Heat pump type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump type water heater capable of reducing generation of overturning phenomenon, and preventing temperature rise of electric components. <P>SOLUTION: This heat pump type water heater comprises a heat pump circuit constituted by successively circularly connecting a compressor 1, a heat exchanger 2 for hot water supply, a pressure reducer 3, and an evaporator 4, an air distribution circuit composed of air distribution fans for distributing the air to the evaporator 4 and vertically disposed, and a hot water circulation circuit constituted by successively circularly connecting a hot water storage tank 7, a water feeding means 8, and the heat exchanger 2 for hot water supply. Electric components 16 for driving each of the heat pump circuit, the air distribution circuit, and the hot water circulation circuit are disposed at an upper portion of the air distribution circuit, and the air distribution fan 6b positioned at a lower part, out of the air distribution fans is stopped. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat pump type water heater, and more particularly to control of two blower fans.

  Some compressors constituting a heat pump cycle in a conventional heat pump type hot water heater use a scroll compressor. FIG. 4 is a structural cross-sectional view of a scroll compressor conventionally used in a compressor such as a heat pump type hot water heater.

  In FIG. 4, when the fixed scroll 101 and the orbiting scroll 102 are engaged with each other, a compression chamber 103 is formed therebetween, and the compression chamber 103 is swung along a circular orbit under the rotation restraint by the rotation restraining mechanism 104. It moves while changing the volume of the refrigerant and compresses the refrigerant.

  Between the orbiting scroll 102 and a fixing member 105 that backs up the back side of the orbiting scroll 102, a high pressure unit 106 that applies high pressure to the back surface of the orbiting scroll 102 with lubricating oil is provided, and a sealing 107 is provided between the orbiting scroll 102 and the high pressure unit 106. A back pressure chamber 108 for applying a pressure (back pressure) slightly lower than that of the high pressure portion 106 is provided on the outer periphery of the back surface, and the orbiting scroll 102 is pressed against the fixed scroll 101 by the high pressure and the back pressure.

  However, when the pressure of the refrigerant compressed in the compression chamber 103 becomes larger than the pressing force due to the high pressure and the back pressure, the orbiting scroll 102 moves away from the fixed scroll 101, and the high pressure compression chamber moves to the low pressure compression chamber. As a result, the refrigerant leaks, cannot be compressed sufficiently, and the compression ability is reduced.

  Generally, at the end of boiling of a heat pump type water heater, the temperature of water entering the heat exchanger for hot water supply rises, so the amount of heat exchange in the heat exchanger for hot water supply decreases and the pressure on the high pressure side increases. End up. On the other hand, as the control at the end of boiling, the increase in the pressure on the high pressure side is suppressed by increasing the amount of water supplied by a circulation pump or opening the opening of the decompression device as the incoming water temperature rises.

However, at the time of high outside air temperature, the pressure on the low pressure side increases compared to that at the time of low outside air temperature, and as a result, the compression ratio represented by the high pressure side pressure / low pressure side pressure is reduced. For this reason, a rollover phenomenon occurs. As a method for avoiding such a rollover phenomenon, there is a method of stopping the rotational speed of the blower fan in order to obtain a high-low pressure difference (see, for example, Patent Document 1).
JP 2005-147545 A

  However, in the method of stopping the rotation of the blower fan, as in Patent Document 1, it is effective if the rollover prevention control is performed at the time of start-up, but the electrical components of the heat pump water heater become relatively high at the end of boiling. Therefore, by stopping the rotation speed of the blower fan, the electrical components are not dissipated and the temperature rises. For this reason, if the blower fan is stopped in the overturning prevention control at the end of boiling, the pressure on the low pressure side can be reduced, but there is a problem that the heat dissipation of the electrical component is hindered.

The present invention solves the above-described conventional problems, and an object of the present invention is to provide a heat pump type water heater that can suppress the occurrence of the overturning phenomenon and also prevent the temperature rise of the electrical components.

  In order to solve the above-described conventional problems, a heat pump type hot water heater of the present invention includes a heat pump circuit in which a compressor, a hot water heat exchanger, a pressure reducing device, and an evaporator are sequentially connected in an annular manner, A hot water tank, a hot water supply means, and a hot water supply circulation circuit in which the hot water supply heat exchanger is sequentially connected in an annular manner, the heat pump circuit, the blower circuit, An electrical component for driving each circuit of the hot water supply circulation circuit is arranged in the upper part of the blower circuit, and the blower fan positioned below among the blower fans is stopped.

  Since this does not stop the blower fan, it is possible to promote the heat dissipation of the electrical components, and furthermore, since the air volume can be reduced compared to when both the upper and lower blower fans are rotating, Since the amount of heat exchange in the evaporator can be reduced and the increase in pressure on the low pressure side can be suppressed, overturning can be prevented at the same time.

  The present invention can provide a heat pump type hot water heater capable of suppressing the occurrence of the overturn phenomenon and preventing the temperature rise of the electrical component.

  The heat pump type hot water heater of the first invention includes a compressor, a heat exchanger for hot water supply, a pressure reducing device, a heat pump circuit in which an evaporator is sequentially connected in an annular manner, and a blower fan that blows air to the evaporator and is arranged up and down. And a hot water supply circulation circuit in which a hot water storage tank, a water supply means, and a hot water supply heat exchanger are sequentially connected in an annular manner, and drives each circuit of the heat pump circuit, the blower circuit, and the hot water supply circulation circuit. By disposing the electrical component to be placed on the upper part of the blower circuit and stopping the blower fan located below among the blower fans, the pressure on the low pressure side is prevented from increasing by reducing the blown amount, and the upper part Since the blower fan located at is operated, the heat dissipation of the electrical component can also be promoted.

  A heat pump type hot water heater according to a second aspect of the present invention includes a compressor, a hot water heat exchanger, a pressure reducing device, a heat pump circuit in which an evaporator is sequentially connected in an annular manner, and a blower fan that blows air to the evaporator and is arranged up and down. And a hot water supply circulation circuit in which a hot water storage tank, a water supply means, and a hot water supply heat exchanger are sequentially connected in an annular manner, and drives each circuit of the heat pump circuit, the blower circuit, and the hot water supply circulation circuit. The electrical component to be arranged at the top of the blower circuit, and the rotational speed of the blower fan located above among the blower fans is greater than the rotational speed of the blower fan located below among the blower fans, Since the pressure on the low-pressure side is suppressed from increasing by reducing the amount of blown air and the blower fan is operated, heat dissipation of the electrical components can also be promoted.

  The heat pump type hot water heater according to the third aspect of the present invention is the first or second aspect of the invention, and further comprises an incoming water temperature detecting means for detecting the temperature of the hot water entering the hot water heat exchanger. By controlling the blower fan located below among the blower fans based on the incoming water temperature to be detected, the blower fan located below is controlled at the end of boiling when the incoming water temperature rises. It is possible to prevent the pressure on the low-pressure side from increasing at the end of boiling where apt to occur.

The heat pump type hot water heater according to a fourth aspect of the invention includes the outside air temperature detecting means for detecting the outside air temperature particularly in the first to third inventions, and the blower fan based on the outside air temperature detected by the outside air temperature detecting means. By controlling the blower fan located below, the blower fan is controlled at the outside air temperature at which the pressure on the low pressure side tends to rise, and the low pressure side at the end of boiling where the overturn phenomenon is more likely to occur. It is possible to prevent the pressure from rising.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a heat pump type hot water heater in the present embodiment. In FIG. 1, the heat pump type hot water heater in the present embodiment includes an inverter compressor 1 that compresses refrigerant, and a heat exchanger 2 for hot water supply that performs heat exchange between the refrigerant compressed by the inverter compressor 1 and water. And a decompressor 3 that decompresses the refrigerant after radiating heat from the heat exchanger 2 for hot water supply, and an evaporator 4 that gives heat to the refrigerant decompressed by the decompressor 3. The inverter compressor 1, heat exchange for hot water supply The vessel 2, the decompression device 3, and the evaporator 4 are connected in a ring shape by a refrigerant pipe 5 to form a heat pump circuit.

  Moreover, it has a blower circuit composed of two blower fans (upper blower fan 6a and lower blower fan 6b) as blower means for sending outside air to the evaporator 4, and further includes an inverter compressor 1 and a decompressor. 3. It has a configuration including a microcomputer 15 which is a control means for controlling the upper and lower two blower fans and the like. And the thermistor 14 which is an outside temperature detection means, and the thermistor 13 which is the incoming water temperature detection means which detects the temperature of the water which enters into the hot water supply heat exchanger 2 are provided.

  In the present embodiment, the inverter type compressor 1 has a compressor configuration without an accumulator, and is smaller and lighter than a compressor configuration having an accumulator. In addition, carbon dioxide is used as the refrigerant used in this embodiment, which is relatively inexpensive and stable, so that the product cost can be suppressed and the reliability can be improved. In addition, since carbon dioxide has an ozone depletion coefficient of zero and a global warming coefficient of about 1/700 that of the alternative refrigerant HFC-407C, it can provide a product that is friendly to the global environment. In addition, since the pressure on the high pressure side of the refrigerant flowing through the heat pump circuit exceeds the critical pressure, it does not condense even if heat is exchanged in the hot water supply heat exchanger 2 and heat is taken away. And it becomes easy to form the temperature difference between a refrigerant | coolant and water over the whole region of the heat exchanger for hot water supply, high temperature hot water can be obtained, and heat exchange efficiency can be made high. In the present embodiment, carbon dioxide is used. However, the present invention is not limited to this. If the high-pressure side exceeds the critical pressure, it is condensed in the hot water supply heat exchanger 2 in the same manner as carbon dioxide. There is nothing to do.

  Moreover, the hot water storage tank 7 which stores hot water and the water pump 8 which is a water supply means which supplies hot water to the hot water supply heat exchanger 2 from the lower part of the hot water storage tank 7 are provided, and the hot water storage tank 7, the water pump 8, and the hot water supply heat exchanger. 2 is connected annularly by a hot water supply pipe 9 to form a hot water supply circuit. Further, a water supply pipe 11 for supplying water from a water supply source is connected to the lower part of the hot water tank 7, and water pressure is always applied.

  When the hot water in the hot water tank 7 is boiled, the water pump 8 is driven to feed water to the hot water supply heat exchanger 2, and the hot water supply heat exchanger 2 exchanges heat with high-temperature and high-pressure carbon dioxide refrigerant. Produces hot water. The hot water generated in the hot water supply heat exchanger 2 is stored in the upper part of the hot water tank 7 from the hot water pipe connected to the upper part of the hot water tank 7, and the upper part of the hot water tank 7 is high in the upper part and low in the lower part. Hot water is stored in a laminated state.

  In addition, the hot water supply terminal 10 such as a curan mixes high temperature water stored in an upper portion of the hot water tank 7 and water supplied by being branched from a water supply pipe 11 for supplying water to the hot water tank 7 by mixing means. It mixes with a certain mixing valve 12, produces | generates the hot water of desired temperature, and has the structure supplied to the hot water supply terminal 10. FIG. In addition, the arrow shown in FIG. 1 has shown the direction through which a refrigerant | coolant or water distribute | circulates.

  FIG. 2 is a front view of the heat pump type water heater in the first embodiment. As shown in FIG. 2, in the first embodiment, all the components of the heat pump type hot water heater are housed in one housing, and the upper blower fan 6 a and the lower blower fan are vertically arranged in front of the evaporator 4. 6b is arranged, and the outside air is sent to the evaporator 4 by rotation of each blower fan. Compared to a separate heat pump type hot water heater in which the heat pump circuit and the hot water supply circuit are configured in separate housings, the space inside the housing can be used without waste by storing all the components in one housing. As a result, the installation space can be saved.

  In addition, an electrical component 16 is disposed above the upper blower fan 6a, and heat radiation is promoted by driving the blower fan.

  Next, control of the upper blower fan 6a and the lower blower fan 6b of the present invention will be described. FIG. 3 is a diagram showing the incoming water temperature and the high and low pressure at the end of boiling. In FIG. 3, the incoming water temperature rises with time. As the incoming water temperature rises, the amount of heat released from the refrigerant in the hot water supply heat exchanger 2 increases, and the high-pressure side pressure and the low-pressure side pressure rise. However, when the high-pressure side pressure rises to a certain level and exceeds the design pressure, a pressure switch (not shown) provided at the discharge port of the compressor works and stops the operation of the heat pump circuit.

  Therefore, in order to prevent an increase in the high-pressure side pressure, the decompression device 3 is driven in the opening direction. As a result, the amount of refrigerant on the high-pressure side moves to the low-pressure side, so that an increase in high-pressure side pressure is suppressed. However, when the opening degree of the decompression device 3 is opened, the low pressure side pressure increases, and as a result, the compression ratio expressed by the high pressure side pressure / low pressure side pressure becomes small. If the compression ratio becomes small and becomes smaller than the compression ratio guaranteed by the compressor, a so-called rollover phenomenon occurs, and a desired compression performance cannot be obtained.

  Further, if the temperature detected by the thermistor 14 which is the outside air temperature detecting means is under an overload condition where the temperature is somewhat high, the operating frequency of the compressor 1 is set to a relatively low operating frequency. Therefore, the operating frequency of the compressor 1 cannot be greatly reduced.

  Therefore, in the present embodiment, in order to secure a compression ratio at the end of boiling in an overload where the outside air temperature detected by the thermistor 14 is relatively high, Control is performed to stop the operation of the blower fan 6b or reduce the rotational speed. In FIG. 3, the operation of the lower blower fan 6b is stopped (or the rotational speed is lowered) from the point B at which the incoming water temperature is gradually increased. Point B is a point at which the incoming water temperature detected by the thermistor 13 serving as the incoming water temperature detection means is a predetermined temperature, and a point at which the incoming water temperature is detected just before the completion of boiling.

  When there is no blower fan stop, as shown by a dotted line in FIG. 3, the high pressure side pressure and the low pressure side pressure rise, and as a result, the compression ratio becomes smaller than the compression ratio A where the overturn phenomenon occurs. However, by stopping the operation of the lower blower fan 6b, it is possible to suppress an increase in the low-pressure side pressure, and as a result, a compression ratio can be secured at a compression ratio A or higher. Since generation | occurrence | production of this is prevented and the driving | operation of the upper ventilation fan 6a is continued, the thermal radiation of the electrical component 16 can be accelerated | stimulated.

  Further, in the present embodiment, the operation of the upper blower fan 6a is a continuous operation, but by intermittently operating the upper blower fan 6a, heat dissipation of the electrical component 16 is promoted and the blower fan is stopped to the maximum. Therefore, it is possible to prevent the lower pressure side pressure from increasing.

  In the present embodiment, when the incoming water temperature is detected to be a predetermined temperature, the operation of the lower blower fan 6b is stopped or the number of rotations is reduced. In addition to the incoming water temperature, the value of the low-pressure side pressure is detected, The blower fan may be controlled based on the value of the low pressure side pressure.

  As described above, at the time of overload when the outside air temperature is high, a plurality of blower fans are provided, and by reducing the rotation speed of some of the blower fans, the heat exchange amount in the evaporator is lowered and the low pressure side pressure is lowered. In addition, since all the blower fans are not stopped, the promotion of heat dissipation of the electrical components is not hindered.

  The heat pump type water heater according to the present invention can be applied to a water heater having a heat pump cycle having a plurality of blower fans.

Configuration diagram of heat pump water heater in Embodiment 1 Front view of heat pump type water heater in embodiment 1 Time variation diagram of pressure and incoming water temperature in the first embodiment Disassembled configuration diagram of a conventional heat pump water heater compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inverter type compressor 2 Heat exchanger for hot water supply 3 Depressurizer 4 Evaporator 5 Refrigerant piping 6 Blower fan 7 Hot water storage tank 8 Water pump 9 Hot water supply pipe 10 Hot water supply terminal 11 Water supply pipe 12 Mixing valve 13 Thermistor 14 Thermistor 15 Microcomputer

Claims (4)

A heat pump circuit in which a compressor, a heat exchanger for hot water supply, a decompression device, and an evaporator are sequentially connected in an annular manner, a blower circuit configured by a blower fan that is blown to the evaporator and disposed above and below, a hot water storage tank, and a water supply And a hot water supply circulation circuit in which the hot water supply heat exchanger is sequentially and annularly connected, and electrical components for driving the heat pump circuit, the blower circuit, and the hot water supply circulation circuit are arranged above the blower circuit. And the heat-pump type water heater characterized by stopping the ventilation fan located below among the said ventilation fans. A heat pump circuit in which a compressor, a heat exchanger for hot water supply, a decompression device, and an evaporator are sequentially connected in an annular manner, a blower circuit configured by a blower fan that is blown to the evaporator and disposed above and below, a hot water storage tank, and a water supply And a hot water supply circulation circuit in which the hot water supply heat exchanger is sequentially and annularly connected, and electrical components for driving the heat pump circuit, the blower circuit, and the hot water supply circulation circuit are arranged above the blower circuit. And the heat pump type hot water supply apparatus characterized by making the rotation speed of the ventilation fan located upward among the said ventilation fans larger than the rotation speed of the ventilation fan located below among the said ventilation fans. Control of a blower fan located below among the blower fans is provided with an incoming water temperature detection means for detecting the temperature of hot water entering the hot water heat exchanger, and based on the incoming water temperature detected by the incoming water temperature detection means The heat pump type water heater according to claim 1 or 2, wherein An outside air temperature detecting means for detecting an outside air temperature is provided, and a blower fan positioned below among the blower fans is controlled based on the outside air temperature detected by the outside air temperature detecting means. 4. The heat pump type hot water heater according to any one of 3 above.

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