JP2003240339A - Heat pump hot water supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an instantaneous water heater type heat pump hot water supply system having superior rising of a hot water supply temperature and controllability and capable of efficiently supplying the hot water. <P>SOLUTION: This instantaneous water heater type heat pump hot water supply system directly passes tap water to a water channel 12 of a heat exchanger 10 exchanging heat between a refrigerant channel a11 and the water channel 12 and uses hot water delivered from the channel. This device is so constituted as to have heating means 18 heating the water in previous/following routes including the water channel 12 of the heat exchanger 10, so that the rising of the hot water supply temperature in starting the hot water supply is quick and its controllability and the efficiency are favorable. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instantaneous boiling type heat pump water heater.

[0002]

2. Description of the Related Art As an instantaneous boiling water heater, a water heater using combustion of gas or oil has been conventionally used.
While these have the characteristics that the temperature rises quickly and can produce large capacity, they have unavoidable problems such as air pollution due to exhaust gas, anxiety about direct combustion, and combustion noise.
On the other hand, there is a heat pump water heater that stores hot water in a large-sized hot water storage tank to solve the problem of the water heater due to combustion, and the heat pump has high thermal efficiency. However, the hot water storage tank was large, and there were problems in construction such as weight and installation space. The idea of instantaneous boiling with a heat pump that solves the problem of this large hot water storage tank has been conventional, but in the case of a heat pump, unlike a combustion water heater, it takes time for the heat pump cycle to rise thermally, so hot water comes out. It took a long time to make the user dissatisfied.

As an instant boiling type heat pump water heater for solving such problems, there has been proposed a water heater as described in JP-A-61-17849.
As shown in FIG. 5, this heat pump water heater has a heat pump cycle 7 in which a compressor 2, a radiator 3, a pressure reducing means 4, and a heat absorber 5 are connected in a refrigerant flow path 1 formed in a closed circuit.
A hot water storage tank 6 that exchanges heat with the radiator 3 is provided, and the hot water storage tank 6 is arranged so as to surround the compressor 2.
With this configuration, when hot water is supplied, the hot water is stored in the hot water storage tank 6, and even if the hot water supply is stopped, the compressor 2 does not cool. Therefore, when the hot water supply is restarted, the rise of the hot water supply temperature is accelerated.

[0004]

In the above-mentioned conventional example, when the hot water storage tank 6 is cooled, the compressor 2 is also cooled, and the heat pump cycle 7 rises, on the contrary, the heat of the compressor 2 is taken by the hot water storage tank 6. To be late. Further, since hot water is discharged from the hot water storage tank 6, when the temperature of the hot water storage tank 6 is cold, the hot water discharge temperature is also cold, and the hot water discharge temperature does not rise until the hot water temperature of the hot water storage tank 6 rises. Therefore, hot water supply from the state where the hot water storage tank 6 is cooled, on the contrary, requires a lot of time until hot water comes out.

Further, if the temperature of the hot water discharged is changed during hot water supply, even if the operating state of the compressor 2 is changed, the temperature of the hot water in the hot water storage tank 6 does not change directly. Will end up.

Further, even if hot water is restarted when there is hot water in the hot water storage tank 6, the hot water storage tank 6 is cooled by the water supply until the heat pump cycle 7 starts up, and the hot water discharge temperature is once lowered. Makes you feel uncomfortable. To prevent this, the hot water storage tank 6 having a sufficiently large capacity is required.

In order to transfer the heat of the refrigerant to the water, the radiator 3 and the hot water storage tank 6 are brought into contact with each other for heat exchange. However, since the hot water storage tank 6 has a capacity, the internal flow velocity is slow even during hot water supply, The heat transfer on the inner surface of the hot water storage tank 6 which is in contact with the radiator 3 cannot be increased. Therefore, the efficiency is low, and a large heat transfer area is required for exchanging a sufficient amount of heat, and the radiator 3 becomes large in proportion to this, and the efficiency is further deteriorated due to an increase in heat dissipation loss. . In addition, the material cost and the manufacturing cost increase with the increase in size, resulting in high cost.

As described above, in the conventional heat pump water heater, the rise of the hot water temperature may be adversely affected,
Moreover, there are problems such as poor controllability of the hot water temperature and deterioration of efficiency.

An object of the present invention is to solve the above-mentioned conventional problems, and an object thereof is to provide a heat pump hot water supply apparatus of the instant boiling type, which has good rise of hot water supply temperature and controllability and can supply hot water efficiently.

[0010]

In order to solve the above-mentioned problems, the present invention provides a heat pump water heater of the present invention in which a tap water is directly supplied to a water flow path of a heat exchanger for exchanging heat between a refrigerant flow path a and a water flow path. It is an instant boiling type that uses hot water that flows through water and is discharged from this water channel, and has a heating means for heating water in the front and rear paths including the water flow path of the heat exchanger.

According to the above invention, the tap water is heated not only by the heat exchanger but also by the heating means, so that even if the heating in the heat exchanger is insufficient, the shortage is compensated for. Can be heated by.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A heat pump water heater according to a first aspect of the present invention is a heat pump cycle in which a compressor, a radiator, a pressure reducing means, and a heat absorber are connected by a refrigerant passage configured in a closed circuit, A heat exchanger having a water flow path for exchanging heat with the refrigerant flow path a of the radiator, a water supply pipe for supplying tap water to the water flow path, and water flow from the water flow path to a hot water supply terminal such as a shower or a faucet A hot water supply circuit that is connected as described above, and a heating means that heats water in at least one portion of a path formed by the water supply pipe, the water flow path, and the hot water supply circuit.

According to the first aspect, the tap water is heated by the heating means separately from the heating by the heat exchanger. Therefore, even if the heating in the heat exchanger is delayed, the heated water temperature rises by the heating means. You can cover the delay. In addition, since the heating means does not directly affect the hot water outlet temperature control by the heat exchanger, the controllability is good. Furthermore, since the heat exchange between the refrigerant and the water is performed by the heat exchanger independently of the heating means, highly efficient heat exchange is possible.

In the heat pump hot water supply apparatus according to a second aspect of the present invention, the heating means according to the first aspect is constituted by a heat storage means provided in series in any one of the water supply pipe, the heat exchanger and the hot water supply circuit. Is.

According to this structure, by storing heat in the heat storage means, even if heating in the heat exchanger is delayed at the start of hot water supply or the like,
Since the heat storage means directly heats the water in any one of the water supply pipe, the heat exchanger and the hot water supply circuit, there is no rise delay in the hot water discharge temperature.

In a heat pump water heater according to a third aspect of the present invention, the heating means according to the first aspect is constituted by a heat storage means connected in parallel to any one of a water supply pipe, a heat exchanger and a hot water supply circuit. Is.

According to this structure, the amount of heat for heating water in any one of the water supply pipe, the heat exchanger and the hot water supply circuit by the heat of the heat storage means can be freely set by changing the flow rate on the heat storage means side.

In the heat pump hot water supply apparatus according to a fourth aspect of the present invention, the heat storage means according to the second or third aspect is one in which water is supplied from the water supply pipe, the heat exchanger or the hot water supply circuit and the water heated by the heat storage means. And a mixing means for mixing and.

According to this structure, the hot water from the heat storage means can be mixed and heated with water in any one of the water supply pipe, the heat exchanger and the hot water supply circuit at a predetermined ratio, so that a predetermined hot water discharge temperature can be immediately obtained.

According to a fifth aspect of the present invention, there is provided the heat pump hot water supply apparatus, wherein the heat storage means according to the second or third aspect is the water flowing from any one of the water supply pipe, the heat exchanger and the hot water supply circuit and the water heated by the heat storage means. It has a switching means for switching and flowing.

According to this structure, the hot water from the heat storage means,
Since it is possible to switch water between the water supply pipe, the heat exchanger, and any water in the hot water supply circuit, the hot water from the heat storage means is used when heating from the heat exchanger is not sufficient when starting hot water supply or when defrosting. It is possible and does not give the user a feeling of dissatisfaction.

In a heat pump water heater according to a sixth aspect of the present invention, the heat storage means according to any one of the second to fifth aspects has a heat retention means A for keeping the heat storage temperature at a predetermined temperature. .

According to this structure, since the hot water of the heat storage means is maintained at a predetermined temperature, even if the hot water supply is started in a state where the compressor and the heat exchanger are completely cold, the hot water of the heat storage means creates a water supply pipe. Since the water in either the heat exchanger or the hot water supply circuit is heated,
The rising temperature of the hot water can always be raised quickly.

In the heat pump water heater of the invention described in claim 7, the heat retaining means A described in claim 6 uses a radiator of a heat pump cycle.

According to this structure, the heat storage of the heat storage means is performed by the heat pump, so that it is more efficient than that of the heater and the like, and the heat pump cycle is driven during the heat retention, so that the temperature rises quickly at the start of hot water supply.

In the heat pump water heater of the invention described in claim 8, the heating means according to claim 1 includes a water circulation path formed by including at least one of a water supply pipe, a water flow path and a hot water supply circuit, and the water circulation. It is constituted by a heat retaining means B for keeping the temperature of circulating water in the passage.

According to this structure, at least one of the water supply pipe, the water flow path, and the hot water supply circuit is kept warm, so that the hot water in the water circulation path is discharged at the start of hot water supply, so that the temperature rises quickly.
Further, the heat of the water circulation path warms the heat exchanger, so the heat pump cycle starts up quickly.

In the heat pump water heater of the invention described in claim 9, the heat retaining means B according to claim 8 uses the water flow path of the heat exchanger to drive the heat pump cycle to retain heat.

According to this structure, the water circulation path is kept warm by the heat pump, so that it is more efficient than a heater or the like, and the heat pump cycle is driven when keeping the heat, so that the heat pump cycle itself starts up faster.

A heat pump water heater according to a tenth aspect of the present invention comprises the water circulation passage according to the eighth or ninth aspect in which heat storage means is provided.

According to this structure, since the hot water when the water circulation path is kept warm is stored in the heat storage means, even if cold water flows into the water circulation path at the start of hot water supply or the like, the hot water is mixed with or replaced by the hot water of the heat storage means to lower the temperature of the hot water. Can be prevented.

In the heat pump water heater of the invention described in claim 11, the heat storage means described in any one of claims 2 to 7 and 10 corresponds to the insufficient heat amount due to the delay in the heat response of the heat pump cycle or the heat exchanger. It is the amount of heat storage.

According to this structure, the size of the heat storage means is optimized, so that the heat storage means is not too large and the heat radiation loss is not increased, and the installation space and weight are not increased.

The heat pump water heater of the invention described in claim 12 is any one of claims 2 to 7 and 10 and 11.
The heat storage temperature of the heat storage means described in the item is set higher than the hot water supply temperature.

According to this structure, the hot water temperature of the heat storage means is set higher than the hot water supply temperature to increase the heat storage density to reduce the heat storage size, and thus the installation space and weight can be reduced.

The heat pump water heater of the invention described in claim 13 is any one of claims 2 to 7 and 10 to 12.
The heat storage means described in the item 1 is provided with a storage tank that stores water at at least one location of a path formed by a water supply pipe, a water flow path, and a hot water supply circuit.

With this configuration, the water used for hot water supply is used as the heat storage means, so that the weight can be reduced by removing the water during distribution. Further, it has a large specific heat as a heat storage material and is safe.

A heat pump water heater according to a fourteenth aspect of the present invention is the heat pump cycle according to any one of the first to thirteenth aspects, wherein the heat pump cycle is a supercritical heat pump cycle in which the pressure of the refrigerant is equal to or higher than the critical pressure. This is a configuration in which the running water in the water flow path of the heat exchanger is heated by the refrigerant that has been boosted to the critical pressure or higher.

Since the refrigerant flowing through the refrigerant flow path a of the heat exchanger is pressurized to a pressure higher than the critical pressure by the compressor, heat is taken by the flowing water in the water flow path of the heat exchanger and the temperature is lowered. Does not condense. Therefore, it becomes easy to form a temperature difference between the refrigerant flow path a and the water flow path in the entire heat exchanger, hot water can be obtained, and heat exchange efficiency can be increased.

A heat pump hot water supply apparatus according to a fifteenth aspect of the present invention is the heat exchanger according to any one of the first to fourteenth aspects, in which the refrigerant flow channel a and the water flow channel have opposite flow directions. By uniformizing the heat transfer between the refrigerant flow path a and the water flow path of the heat exchanger, it is possible to obtain high-temperature hot water with good heat exchange efficiency.

[0041]

Embodiments of the present invention will be described below with reference to the drawings. In the conventional example and each example, the same reference numerals are given to the parts having the same configurations and the same operations, and detailed description thereof will be omitted.

(Embodiment 1) FIG. 1 is a configuration diagram of a heat pump type hot water supply apparatus according to Embodiment 1 of the present invention. In FIG. 1, 7 is a heat pump cycle, and the compressor 2, the radiator a8, the radiator b9, the pressure reducing means 4, and the heat absorber 5 are the refrigerant flow path 1.
Connected to a closed circuit. The heat pump cycle 7 uses, for example, carbon dioxide as a refrigerant, and uses a supercritical heat pump cycle in which the refrigerant pressure on the high pressure side is equal to or higher than the critical pressure of the refrigerant. The compressor 2 is driven by a built-in electric motor (not shown) and compresses the sucked refrigerant to a critical pressure and discharges it. Further, 10 is a water flow path 12 for exchanging heat with the refrigerant flow path a11 of the radiator b9.
Is a heat exchanger equipped with. A water supply pipe 13 for directly supplying tap water to the water flow path 12 and a hot water supply circuit 15 for connecting hot water discharged from the water flow path 12 to a hot water supply terminal 14 including a shower 16 and a faucet 17 are connected. . 18 is a heating means for heating the water in the hot water supply circuit 15, which comprises a heat storage means 20 connected in parallel to the hot water supply circuit a19 at the upstream part of the hot water supply circuit 15. The heat storage means 20 is the hot water supply circuit 1
5 is composed of a storage tank 21 for storing the flowing water, and a mixing means 22 for mixing the flowing water of the hot water supply circuit a19 and the heat storage means 20. The storage tank 21 has an inlet pipe 23 at the lower end, an outlet pipe 24 at the upper end, and a radiator a8 built in at the lower part, and is covered with a heat insulating material 25. The radiator a8 also serves as a heat retaining unit A for keeping a heat storage temperature (hereinafter referred to as a storage temperature) in the hot water storage tank 21 at a predetermined temperature. Hot water supply circuit 15
Is branched from the branching portion 26 into the hot water supply circuit a19 and the inlet pipe 23, and the confluence portion 27 joins the water in the hot water supply circuit a19 and the outlet pipe 24. The merging unit 27 is provided with the mixing means 22.

The size of the storage tank 21 is set to a heat storage amount corresponding to an insufficient heat amount due to a thermal response delay when the heat pump cycle 7 and the heat exchanger 10 discharge hot water. For example, the feed water temperature is 5 ° C. and the target temperature is 45 ° C. If hot water is supplied at 10 L / min, and there is a delay of 3 minutes before tapping at the target temperature, the heat deficit is ((45 ℃ -5 ℃) × 10L / min × 3min / 860) It will be 4kWh. If this is supplemented by the hot water storage tank 21 of 80 ° C. (1.4 kWh × 860 / (80 ° C.-5 ° C.)), the capacity is 16 L.

The water supply pipe 13 is provided with a flow rate detecting means 28 for detecting the flow rate of the hot water supply circuit 15 and a water temperature detecting means 29 for detecting the temperature of the water supplied to the heat exchanger 10. The hot water supply circuit 15 has hot water temperature detecting means 30 for detecting the hot water temperature.
Is provided. Further, a storage temperature detecting means 31 for detecting the temperature of the hot water in the storage tank 21 is provided above the storage tank 21. Reference numeral 32 is an air temperature detecting means for detecting the air temperature. Reference numeral 33 is a temperature setting means for setting a target temperature for hot water supply, and the user arbitrarily sets the temperature.

Reference numeral 34 is a control means which, when the flow rate detecting means 28 detects the flow rate, calculates the feedback control amount from the deviation between the hot water temperature output means 30 and the temperature setting means 33 and the target temperature. , Water temperature detection means 2
9, the hot water supply load is calculated from the respective values of the temperature setting means 33 and the flow rate detecting means 28, the feedback control amount and the hot water supply load are added, and the rotation speed of the compressor 2 is controlled based on the added value.

Further, the control means 34 includes the temperature detecting means 32.
The number of revolutions of the compressor 2 is corrected according to the detected value of
The depressurizing unit 4 and the blower 35 are individually controlled to operate in the heat pump cycle with the highest efficiency.

Further, the control means 34 drives the mixing means 22 to control the mixing ratio of the flowing water from the hot water supply circuit a19 and the flowing water from the storage tank 21 to bring the hot water outlet temperature close to the target temperature.

When the hot water supply is stopped, the control means 34 detects the storage temperature from the storage temperature detecting means 31, and controls the compressor 2 to rotate at a low speed so as to keep the storage temperature at a predetermined temperature (for example, 80 ° C.) and keep it warm. drive. The heat storage density can be increased and the size of the storage tank 25 can be reduced by making the predetermined temperature of this heat retention sufficiently higher than the target temperature of hot water supply (for example, 45 ° C.).

The heat exchanger 10 is constructed so that the flow direction of the refrigerant flow path a11 and the flow direction of the water flow path 12 are opposed to each other, and the flow paths are closely contacted with each other to facilitate heat transfer. With this configuration, the heat transfer in the refrigerant channel a11 and the water channel 12 is made uniform, and the heat exchange efficiency is improved. Also, hot water can be discharged.

The operation and action of the above structure will be described. In the embodiment shown in FIG. 1, when the faucet 17 is opened, tap water starts to flow from the water supply pipe 13. This is detected by the flow rate detecting means 28, a signal is sent to the control means 34, and the operation of the compressor 2 is started. At this time, when the heat pump cycle 7 is in a completely cold state, even if the compressor 2 is operated, the pressure and temperature of the entire cycle have not reached the steady state, so that water close to the feed water temperature is discharged from the water flow passage 12. I will end up. The control unit 34 sets the mixing ratio of the mixing unit 22 to, for example, 1: 1 for a predetermined time (for example, 3 minutes) after the hot water supply is started. Here, assuming that the supply water temperature is 5 ° C. and the storage temperature is 80 ° C., and the outlet temperature from the water channel 12 is still 5 ° C., the outlet temperature of the mixing means 22 is (80 ° C. + 5).
(° C) / 2, the tapping temperature is 42.5 ° C. After that, the outlet temperature of the water channel 12 gradually rises, but the storage tank 2
As for the storage temperature in 1, the cold water, which is close to the feed water temperature, flows in from the inlet pipe 23, and therefore the outlet temperature of the storage tank 21 is gradually decreased. Therefore, the outlet temperature of the mixing means 22 is the target temperature of hot water supply (for example, 45 when the respective running waters are mixed).
C.) can be maintained.

As described above, the control of the mixing means 22 operates so as to compensate for the delay of hot water output from the heat exchanger 10 by utilizing the hot water from the hot water storage tank 21 immediately after the start of hot water supply. When the temperature of the heat exchanger 10 is not cooled at the start of hot water supply, the hot water temperature detecting means 30 outputs a value higher than the target temperature. In this case, the mixing ratio should be the hot water supply circuit a19.
Adjust so that the hot water temperature approaches the target by increasing the number of sides.

When the temperature of the heat pump cycle 7 becomes stable, the mixing ratio of the mixing means 22 is adjusted to the hot water supply circuit a19.
Switch to the subject. At this time, the high-temperature and high-pressure refrigerant gas discharged from the compressor 2 flows into the radiator a8 and the radiator b9, heating the water in the storage tank 21 and the water flowing in the water flow passage 12. The heated water is supplied to the hot water supply circuit a.
19, hot water is discharged from the hot water supply terminal 12 through the hot water supply circuit 15.
On the other hand, the refrigerant cooled by the radiator a8 and the radiator b9 is decompressed by the decompression means 4 and flows into the heat absorber 5, where atmospheric heat,
It absorbs natural energy such as solar heat, evaporates it into gas, and returns to the compressor 2.

The control means 34 during hot water supply calculates the feedback control amount from the deviation between the hot water discharge temperature and the target temperature using known PID control. The proportional gain, the integral coefficient, and the differential coefficient, which are the control constants here, need to be set in advance to optimal values for achieving both control response and stability. The feedback control may be PI control, P control, fuzzy or neuro control. On the other hand, the hot water supply load is calculated by multiplying the difference between the target temperature and the water supply temperature by the flow rate detected by the flow rate detection means 20. This is a so-called feedforward control amount. Then, the feedback control amount and the hot water supply load are added, and the rotation speed control of the compressor 2 is performed using the added value. By adding this feedback control, the outlet heated water temperature can be accurately controlled to the target temperature. Especially PID and PI
By using the integral element as in the control, the hot water outlet temperature can be adjusted to the target temperature more. Further, by using the proportional control element, the responsiveness is improved because the heating control is performed with a large capacity when the tapping temperature is low immediately after the start of hot water supply. On the other hand, the feedforward control is a required amount of heat when the temperature of the hot water supply is stable, so that the amount of heat is not excessive and insufficient, and the control stability is excellent. Further, when the hot water supply flow rate or the water supply temperature suddenly changes, the amount of heating can be changed and controlled immediately, so that this point is more responsive and more stable than the feedback control. Since the feedback control and the feedforward control are added and controlled, it is possible to make use of their respective characteristics and control with good responsiveness and stability.

Next, the operation when the hot water supply is stopped will be described.
Although the storage tank 21 is covered with the heat insulating material 25, the storage temperature gradually decreases due to heat radiation. This is detected by the storage temperature detection means 31, and the storage temperature is set to the lower limit temperature (for example, 75
(° C), the compressor 2 is rotationally controlled at a low speed and heated by the radiator a8 to raise the temperature in the storage tank 25. At this time, the radiator b9 is also heated, but the water flow path 1
Since there is no flow in 2, if the heat exchanger 10 warms up, no more heat will be taken away. Then, when the storage temperature exceeds a predetermined temperature (for example, 80 ° C.), the operation of the compressor 2 is stopped. In this way, the heat retention operation is performed so that the temperature of the storage tank 21 is maintained near the predetermined temperature.

Although the radiator a8 is provided inside the storage tank 21 in the first embodiment, the radiator a8 may be closely attached to the outer periphery of the storage tank 21, for example, by winding a radiator around the outer periphery. Further, the heat retention of the storage tank 21 may be performed by a general heater instead of the radiator a8.

In the first embodiment, the heat pump cycle is a supercritical heat pump cycle in which the pressure of the refrigerant is higher than the critical pressure, but it is of course possible to use a heat pump cycle under the general critical pressure. This also applies to each embodiment described below.

In the first embodiment, the mixing means 22 is controlled so as to change the mixing ratio according to the elapsed time and the mixing temperature at the start of hot water supply.
A switching means (not shown) may be used to switch between the flowing water and the flowing water of the hot water supply circuit a19. In this case, the storage tank 2
The storage temperature of 1 is set to the target temperature of hot water supply, and when the outlet temperature from the water flow path 12 rises to near the target temperature, control is performed to switch the flow from the storage tank 21 to the hot water supply circuit a19. According to this structure, the mechanism and control of the switching means are simpler than those of the mixing means 22, and the cost is reduced.

(Embodiment 2) FIG. 2 is a block diagram of a heat pump water heater in Embodiment 2 of the present invention. In addition, the same reference numerals are given to those having the same structure as the hot water supply device of the first embodiment,
The description is omitted. In FIG. 2, the difference from the configuration of the first embodiment is that the heating means 40 is configured by a heat storage means 41 provided in series with the hot water supply circuit 15. Heat storage means 41
Is different in that the inlet pipe 43 is arranged above the storage tank 42 and the mixing means is configured inside the hot water storage tank 42. The storage temperature of the storage tank 42 during the heat retention operation is set to be equal to the target temperature of hot water supply (for example, 45 ° C.). However, the lower the storage temperature, the larger the capacity of the storage tank 42.

With the above construction, when hot water supply is started from the state where the heat exchanger 10 is completely cooled, cold water close to the water supply temperature flows from the inlet pipe 43 into the storage tank 42. Then, in the storage tank 42, the inflow water flows into the bottom of the storage tank 42 due to the temperature difference from the hot water inside, and only the hot water therein is discharged from the outlet pipe 24. Therefore, it is possible to discharge hot water close to the target temperature for hot water supply immediately after the start of hot water supply. Inlet pipe 43
When the temperature flowing in from the outlet rises, it is mixed with the hot water in the upper portion in the storage tank 42 and is discharged from the outlet pipe 24. When tapping hot water at a temperature higher than the storage temperature,
Hot water having a temperature higher than the storage temperature flows from the inlet pipe 43 into the storage tank 42. In this case, since the specific gravity of the inflowing water is light, it flows to the upper end of the storage tank 42 and is discharged as it is from the outlet pipe 24. In this way, hot water mixing is performed in the storage tank 42.

As described above, in the second embodiment, the hot water supply circuit 15
By simply connecting the heat storage means 41 in series to the hot water supply system, it is possible to compensate for the delay of hot water supply at the start of hot water supply and realize hot water supply with stable temperature. Further, the cost can be reduced because the mixture can be naturally mixed at an appropriate temperature inside the storage tank 42 without any mixing means.

(Embodiment 3) FIG. 3 is a block diagram of a heat pump water heater in Embodiment 3 of the present invention. The components having the same structures as those of the hot water supply devices according to the first and second embodiments are designated by the same reference numerals, and the description thereof will be omitted. In FIG. 3, the difference from the configuration of the second embodiment is that the heating means 50 is connected to the water supply pipe 1.
It is configured by the heat storage means 51 provided in series with the No. 3. Another difference is that an inlet pipe 53 is arranged at the bottom of the storage tank 52 of the heat storage means 51. The storage temperature of the storage tank 52 during the heat retention operation is set to be equal to the target temperature of hot water supply (for example, 45 ° C.).

With the above construction, when hot water supply is started from the state where the heat exchanger 10 is completely cooled, cold water flows into the bottom of the storage tank 52 from the water supply pipe 13, and hot water of the storage tank 52 is discharged from the outlet pipe 54. To be done. When the heating amount of the heat exchanger 10 increases, the rotation speed of the compressor 2 is controlled by the temperature detected by the hot water temperature detecting means 30, and the hot water temperature of the target temperature can be maintained.

As described above, in the third embodiment, the heat exchanger 10
Since the heat storage means 51 is disposed on the upstream side of, the heat storage means 51 compensates when the heating of the heat exchanger 10 is delayed,
When the heating capacity of the heat exchanger 10 rises, the compressor 2 is controlled by the feedstock control of the outlet heated water temperature, and the target hot water supply temperature can always be maintained. Further, even if the target temperature is changed, the hot water outlet temperature can be directly changed.

Furthermore, since the heat exchanger 10 is warmed by the hot water in the storage tank 52 at the start of hot water supply, the temperature of the heat pump cycle 7 rises quickly.

In the third embodiment, the heat storage means 51 is arranged in series with the water supply pipe 13, but the heat storage means 51 is arranged in parallel with the water supply pipe 13 so that the storage temperature is higher than the target temperature of the hot water supply and the flowing water of the water supply pipe 13 is used. By mixing the hot water of the heat storage means to a temperature close to the target temperature and flowing it to the heat exchanger 10, the heat storage means can be downsized by high temperature heat storage.

Further, although the heat storage means is arranged downstream of the heat exchanger 10 in the first and second embodiments and is arranged upstream in the third embodiment, the heat storage means are arranged in parallel so as to bypass the heat exchanger 10. The water flowing in the water flow path and the water flowing in the heat storage means may be arranged to be mixed on the upstream side of the heat exchanger. further,
The same effect can be obtained by arranging the heat storage means so as to incorporate the heat exchanger therein.

(Embodiment 4) FIG. 4 is a block diagram of a heat pump water heater in Embodiment 4 of the present invention. In addition, the same reference numerals are given to those having the same structure as the hot water supply device of the first embodiment,
The description is omitted. In FIG. 4, the difference from the configuration of the first embodiment is that the heating means 60 is configured by a water circulation passage 61 formed to include the water passage 12 and a heat storage means 62 arranged on the water circulation passage 61. is there. Then, as the heat retention means B (not shown) for maintaining the temperature of the circulating water of the water circulation path 61 and the heat storage means 62, the heat pump cycle 7 is driven to heat the water flow path 12 of the heat exchanger 10,
Natural convection is generated in the water circulation path 61 to keep it warm by heating. The heat storage means 62 is composed of a storage tank 63 in which the inlet pipe 23 and the outlet pipe 24 are arranged vertically, and a mixing means 22 for mixing the flowing water from the outlet pipe 24 and the flowing water from the water flow path 12 and causing the mixture to flow out to the hot water supply pipe 15. ing. The water circuit 61
The water flow path 12, the mixing means 22, and the storage tank 63 are configured to communicate in a loop.

With the above structure, when the hot water supply is started from the state where the heat exchanger 10 is completely cooled, the cold water flows from the water supply pipe 13 into the water flow passage 12 and the storage tank 63, and the cold water is discharged from the outlet of the water flow passage 12. The hot water from the storage tank 52 is mixed with the mixing means 22.
Are mixed and discharged to the hot water supply circuit 15. At this time, since the opening degree of the mixing means 22 is determined by the temperature detected by the hot water temperature detecting means 30, the temperature of hot water discharged to the hot water supply circuit 15 can be controlled to the target temperature. Then, when the heating amount of the heat exchanger 10 increases, the rate of hot water discharged from the storage tank 63 decreases due to the temperature detected by the hot water temperature detection means 30, and the hot water discharged from the water flow path 12 reaches the target temperature and is stored. The tapping from the tank 63 is stopped.

When the hot water supply is stopped, the amount of heat stored in the storage tank 63 is lowered by the water supply flowing into the hot water supply.
Here, the control unit 34 first returns the mixing unit 22 to the mixed state, and when the storage temperature detecting unit 31 detects a decrease in the storage temperature (for example, 75 ° C. or lower), drives the heat pump cycle 7 to reduce the speed of the compressor 2 to a low speed. Drive by spinning. As a result, the high-temperature and high-pressure refrigerant flows into the refrigerant channel a11 and heats the water channel 12. When the water temperature in the water flow path 12 rises and becomes higher than the water temperature in the storage tank 63, the water in the water flow path 12 rises due to the temperature difference between the two, and convection occurs in the water circulation path 61. Then, when the temperature inside the storage tank 63 rises and the detected temperature of the storage temperature detecting means 31 exceeds a predetermined temperature (for example, 80 ° C.), the operation of the heat pump cycle 7 is stopped. By repeating this operation stop, the heat storage means 62 and the circulating water in the water circulation path 61 are kept warm.

According to the configuration of the fourth embodiment described above, the water flow path 1
Since the water circulation path 61 including the heat storage means 62 and the heat storage means 62 is kept warm and the hot water in the water circulation path 61 is discharged at the start of hot water supply,
The temperature of the hot water discharged from the hot water supply terminal 14 rises faster. Further, since the heat of the water circulation path 61 warms the heat exchanger 10 when the heat pump cycle 7 is stopped, the heat pump cycle 7 starts up faster.

Further, since the water circulation path 61 is kept warm by the heat pump, it is more efficient than a heater or the like and there is no fear of freezing.

Further, the hot water is stored in the heat storage means 62, and the mixing means 22 mixes the hot water at an appropriate temperature to discharge hot water. Therefore, even if cold water flows into the water circulation path 61 at the time of starting hot water supply, etc., it is possible to prevent a decrease in the hot water discharge temperature. You can

In the fourth embodiment, the circulation of water in the water circulation passage 61 in the heat retention operation uses the flow of natural convection, but a water circulation passage 61 may be provided with a pump to forcibly circulate it. In this case, since a constant flow rate can be obtained, it is easy to control the storage temperature and the heating heat quantity in the heat exchanger.

Further, although the mixing ratio is changed by the mixing means 22 in the fourth embodiment, it may be constituted by a merging member fixed at a fixed ratio. In this case, it is necessary to control the heating amount of the heat exchanger 10 by the compressor 2 so that the outlet heated water temperature becomes the target temperature in accordance with the decrease in the hot water in the storage tank. With this configuration, the cost of the mixing means 22 can be reduced.

Further, in the fourth embodiment, the heat storage means 62 is arranged in the water circulation path 61, but the water circulation path 61 alone may be omitted without the heat storage means 62. In this case, the storage temperature detecting means 31 is arranged so as to detect the temperature of the circulating water in the water circulation passage 61, and the heat retaining operation is performed to keep the temperature of the circulating water at a predetermined temperature. With this configuration, the tapping temperature fluctuates slightly, but the cost is greatly reduced.

In the fourth embodiment, as the heat retaining means B, the heat pump cycle 7 is driven to heat the water flow passage 12 of the heat exchanger 10 so that natural convection is generated in the water circulation passage 61 to keep it warm. 61 may be directly heated by a heater, or in a storage tank, the heat pump cycle 7 becomes more efficient as the temperature difference between the refrigerant passage a8 and the water passage 9 becomes smaller in the normal hot water supply use state. In accordance with the supply water temperature detected by 21, the required amount of heat in the heat exchanger 10 is secured, and the refrigerant flow path resistance of the pressure reducing means 4 is adjusted so that the temperature difference between the refrigerant flow path a8 and the water flow path 9 is minimized. Controlling enables efficient operation.

[0077]

As described above, according to the present invention, it is possible to provide a heat pump hot water supply apparatus of the instant boiling type, which has good control of hot water supply temperature and controllability, and can supply hot water efficiently.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a heat pump water heater according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a heat pump water heater according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a heat pump water heater according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram of a heat pump water heater according to a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional heat pump water heater.

[Explanation of symbols]

1 Refrigerant flow path 2 compressor 4 decompression means 5 heat absorber 7 heat pump cycle 8 Radiator a (heat retention means A) 9 Radiator b 10 heat exchanger 11 Refrigerant flow path a 12 Water flow path (heat retention means B) 13 Water supply pipe 14 Hot water supply terminal 15 Hot water supply circuit 16 showers 17 faucet 18, 40, 50, 60 Heating means 19 Hot water supply circuit a 20, 41, 51, 62 Heat storage means 21, 42, 52, 63 Storage tanks 22 Mixing means 61 water circuit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ryuta Kondo             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Satoshi Matsumoto             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Satoshi Imabayashi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd.

Claims (15)

[Claims] 1. A compressor with a refrigerant flow path configured in a closed circuit,
A heat pump cycle to which a radiator, a decompression means, and a heat absorber are connected, a heat exchanger having a water passage for exchanging heat with the refrigerant passage a of the radiator, and a water supply pipe for supplying tap water to the water passage. And heating water in at least one part of a path constituted by the hot water supply pipe, the water flow path and the hot water supply circuit, and a hot water supply circuit connected so as to pass water from the water flow path to a hot water supply terminal such as a shower or a faucet. A heat pump water heater having a heating means. 2. The heat pump hot water supply apparatus according to claim 1, wherein the heating means is a heat storage means provided in series in any one of the water supply pipe, the heat exchanger, and the hot water supply circuit. 3. The heat pump water heater according to claim 1, wherein the heating means is a heat storage means connected in parallel to any one of the water supply pipe, the heat exchanger and the hot water supply circuit. 4. The heat pump water heater according to claim 2, wherein the heat storage means has a mixing means for mixing flowing water of any one of the water supply pipe, the heat exchanger, and the hot water supply circuit and the water heated by the heat storage means. . 5. The heat pump hot water supply according to claim 2 or 3, wherein the heat storage means has a switching means for switching and flowing the running water of any one of the water supply pipe, the heat exchanger and the hot water supply circuit and the water heated by the heat storage hand. apparatus. 6. The heat pump water heater according to claim 2, wherein the heat storage means has a heat retention means A for keeping the heat storage temperature at a predetermined temperature. 7. The heat pump water heater according to claim 6, wherein the heat retaining means A uses a radiator of a heat pump cycle. 8. The heating means comprises a water circulation path formed by including at least one of a water supply pipe, a water flow path and a hot water supply circuit, and a heat retention means B for maintaining the temperature of the circulating water in the water circulation path. The heat pump water heater according to claim 1. 9. The heat retaining means B uses a water flow path of a heat exchanger to drive a heat pump cycle to retain heat.
The heat pump water heater described in. 10. The water circulation path is provided with heat storage means.
Alternatively, the heat pump water heater according to 9. 11. The heat pump water heater according to claim 2, wherein the heat storage means has a heat storage amount corresponding to an insufficient heat amount due to a heat response delay of a heat pump cycle or a heat exchanger. 12. The heat pump hot water supply apparatus according to claim 2, wherein the heat storage means sets the heat storage temperature higher than the hot water supply temperature. 13. The heat storage means comprises a storage tank for storing water in at least one location of a path formed by a water supply pipe, a water flow path, and a hot water supply circuit. The heat pump water heater according to the item. 14. The heat pump cycle is a supercritical heat pump cycle in which the pressure of the refrigerant is equal to or higher than the critical pressure, and the flowing water in the water flow path of the heat exchanger is heated by the refrigerant whose pressure is increased to the critical pressure or higher. Any one of 13
The heat pump water heater according to the item. 15. The heat pump water heater according to claim 1, wherein the refrigerant flow path a and the water flow path of the heat exchanger have opposite flow directions.