JPS58153057A - Heat pump type hot-water supply device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat pump water heater, and one of its objects is to enable continuous operation even at low outside temperatures.

A conventional heat pump water heater will be explained with reference to FIG. 1.

In FIG. 1, reference numeral 1 denotes a hot water storage tank, which is connected to a heat pump device 2 by a water pipe 3.

The heat pump device 2 includes a compressor 4. It consists of a refrigerant circuit consisting of a heat sink 8 equipped with a heat radiator 6, an expander 6, and a fan 7. On the other hand, on the hot water tank 1 side, the water pipe 3
Together with the pump 9 and the radiator 5, a circular water circuit is formed through the pump 9 and the radiator 5.

In the above configuration, the refrigerant discharged from the compressor 4 passes through the radiator 5, passes through the expander 6, and then the heat absorber 8, and returns to the compressor 4 again to form a frozen cycle.

On the other hand, the water pumped from the hot water tank 1 by the pump 9 passes through the radiator 5 and then returns to the hot water tank 1, forming a water cycle. During this time, heat is transferred from the outside air to the refrigerant in the heat absorber 8, and heat is transferred from the refrigerant to the water in the shattered radiator 5, so the water that has passed through the radiator 6 becomes high temperature and is stored in the tank 1. , can be stored. Hot water is obtained by the heat pump water heater through the following operations.

However, when the temperature of the outside air is low, the temperature of the heat absorber 8 decreases, and when the outside air temperature falls below a certain level, frost forms on the heat absorber 8, making it difficult to exchange heat in the heat absorber 8. Therefore, the ability of the radiator 6 to heat water decreases, and as frost formation progresses, the radiator 6 hardly heats the water.

Therefore, the present invention solves the drawbacks of the conventional heat pump type water heater described above and is designed to continuously heat water even when the outside temperature is low.

Hereinafter, a heat pump water heater according to an embodiment of the present invention will be described with reference to FIG. 2.

In Fig. 2, 10 is a hot water storage tank, and a heat pump device 1
1 through a water pipe 12. The heat pump device 11 includes a compressor 13. A heat radiator 14, an expander 16, and a heat absorber 17 equipped with a fan 16 are sequentially connected in an annular manner through refrigerant pipes to form a refrigerant circuit. In addition, the hot water storage tank 10
constitutes a water circuit equipped with a pump 18. This water circuit includes a main heat exchange section 12a (for example, a double pipe structure), a part of which exchanges heat with the radiator 14, and a main heat exchange section 12a (for example, a double pipe structure).
4 and the hot water storage tank 10, a branch portion 12b is provided in which the water flow path is branched into two via a switching valve 19. One of the branch portions 12b is simply made of a straight pipe 2o, and the other is connected to a heater 21 made of a meandering pipe. This heater 21 is provided adjacent to or in contact with the heat absorber 1.

The control circuit 23 is activated by a signal from the frost detection sensor 22 that detects the presence or absence of frost formation on the heat absorber 17, and the cut-off switching valve 19 directs the hot water flowing through the main heat exchange section 12L to the straight pipe 2o. Alternatively, it operates to selectively flow to the heater 21. Further, the frost detection sensor 22 may be a thermistor that detects the temperature of the outside air or a detection element that detects the temperature or pressure of the heat absorber 17 as a means for detecting the presence or absence of frost on the heat absorber 17.

Next, the operation of the above configuration will be explained.

The refrigerant discharged from the compressor 13 without being separated passes through the radiator 14, passes through the expander 16 and the heat absorber 17, and returns to the compressor 13 again to form a frozen cycle.

On the other hand, water pumped up from the hot water tank 10 by the pump 18 passes through the radiator 14, but when the outside air temperature is relatively high, that is, when heat can be absorbed from the outside air, the water is passed through the straight pipe 20 through the switching valve 19. A water cycle is formed in which the water flows to the hot water tank 1o and returns to the hot water storage tank 1o. During this time, heat is transferred from the outside air to the refrigerant in the heat absorber 1, and heat is transferred from the refrigerant to the water in the radiator 14, and the water that exits the radiator 14 becomes high temperature and The hot water passes through the straight pipe 2o and is stored in the hot water storage tank 1o.

On the other hand, when the outside air temperature falls below a certain temperature at which frost builds up on the heat absorber 17, the control circuit 23 is activated by a signal from the frost detection sensor 22, and the switching valve 19 is switched.
Water pumped up from the hot water tank 10 by the pump 18 passes through the radiator 14 and becomes high temperature. The water then passes through the heater 21 via the switching valve 19 and returns to the hot water storage tank 10 again. In the heater 21, the heat absorber 17 is heated by a portion of the heat of the high water flowing through the heater 21.

Therefore, frost formation and development on the heat absorber 17, which occurs when the outside air is low, is not observed, and the heat pump water heater can be operated continuously. Note that part of the heat added to the water in the heat radiator 14 is used in the heater 21 to heat the heat absorber 17, but that heat is pumped up in the heat absorber 17 and heated to water again in the heat radiator 14. Therefore, it has almost no effect on the heating capacity of the heat pump water heater.

Next, one embodiment of the control circuit 23 will be described with reference to FIG. 3. However, in this figure, the same parts as those in FIG. 2 are given the same numbers and the explanation will be omitted.

In FIG. 3, reference numeral 24 denotes an AC power supply, which connects the transistor 27 and the switching valve whose base voltage is the potential between the frost detection sensor 22 and the comparison resistor 26 via an AC-DC converter 26. Electromagnetic coils 29 and the like are connected in series to control the switching of '19.

In the configuration of -1- below, when the temperature of the outside air is high, the resistance of the frost detection sensor 22 is small, so the base voltage of the transistor 27 is small and the electromagnetic coil 29 is not energized, and the switching valve 19 is used as a water flow path. Select straight pipe 2o. However, [7] When the temperature of the outside air becomes low enough to cause frost to form on the heat absorber 17, the resistance of the frost detection sensor 22 increases, and the base voltage of the transistor 27 increases, causing electromagnetic The coil 29 is energized, the electromagnetic coil 29 is excited, and the switching valve 19 is switched. As a result, hot water passing through the radiator 14 is transferred to the heater 2.
Pass through 1.

In this embodiment, the flow of hot water is switched by the switching valve 19, but an on-off valve is provided on the heater 21 side so that if frost occurs, the hot water is diverted to the straight pipe 20 and the heater 21. You can also run warm water over it.

In addition, although heat exchange (thermal conduction) between the water circuit and the refrigerant circuit is performed using a double pipe structure, it is also possible to use a structure in which the heat radiator 14 and the main heat exchange section 122L share the heat radiating fins or other structures. good.

As is clear from the above embodiments, the heat pump water heater of the present invention includes a refrigerant circuit equipped with a compressor, a heat absorber, an expander, and a radiator, and a water circuit equipped with a circulation pump and a hot water storage tank. The circuit is provided with a main heat conduction section that conducts heat with the radiator, and the front water distribution circuit further includes an auxiliary heating section that heats the heat absorber, a branch section that branches in parallel with the auxiliary heating section, and a main heat conduction section that conducts heat with the radiator. A valve device is provided that allows the hot water flowing through the conduction section to flow to the auxiliary heating section, and the valve device is configured to supply the hot water to the auxiliary heating section in response to a frost detection signal from a frost detection element that detects frost formation on the heat absorber. It operates in a flowing manner,
By detecting frost formation on the heat absorber, hot water is flowed to the auxiliary heating part to heat the heat absorption part, so it can be used at low outside temperatures when normal continuous operation is impossible due to frost formation on the heat absorber. Since the water circuit can be heated continuously and the heat of the hot water is recovered, it has various advantages such as efficient and easy-to-use hot water supply.

[Brief explanation of drawings]

Figure 1 is a configuration diagram of a conventional heat pump water heater;
The figure is a configuration diagram of a heat pump water heater according to an embodiment of the present invention, and FIG. 3 is a schematic control circuit diagram of the heat pump water heater. 1o...Hot water storage tank, 12&...Main heat exchange section, 12b...Branch section, 13...Compressor, 1
4... Heat sink, 16... Expander, 17...
... Heat absorber, 18 ... Pump, 19 ...
... Switching valve (valve device), 21 ... Heater (auxiliary heating section), 22 ... Frost detection sensor, 23 ...
...control circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] A refrigerant circuit equipped with a compressor, a heat absorber, an expander, and a radiator, and a water circuit equipped with a circulation pump and a hot water storage tank are provided, and the water circuit is provided with a main heat conduction part that conducts heat with the radiator, Further, in the water circuit, an auxiliary heating section that heats the heat absorber, and a branch section branched in parallel with the auxiliary heating section;
A valve device is provided that allows hot water flowing through the main heat conduction section to flow to the auxiliary heating section, and this valve device is connected to the auxiliary heating section by a frost detection element of a frost detection element that detects frost formation on the heat absorber. A heat pump type water heater that operates to flow hot water to.