JPH0361108B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a heat pump water heater using a hydrogen storage alloy, and particularly relates to a tank heat exchanger that heats water in a hot water storage tank, and a heat source. a compressor that circulates and flows refrigerant from the tank heat exchanger to the heat source heat exchanger, and a first hydrogen storage alloy and hydrogen provided in the hot water storage tank. the first auxiliary heat exchanger, and the first auxiliary heat exchanger
a second auxiliary heat exchanger connected to an auxiliary heat exchanger and provided outside the hot water storage tank, and containing hydrogen and a second hydrogen storage alloy having different temperature-hydrogen pressure characteristics from the first hydrogen storage alloy; This invention relates to a heat pump type water heater that utilizes a hydrogen storage alloy consisting of.

(Prior Art) This type of heat pump water heater is disclosed in Japanese Patent Application Laid-open No. 8648/1983.

FIG. 3 is a configuration diagram of the system, in which a tank heat exchanger 102 for heating water in a hot water storage tank 101 is provided, and the tank heat exchanger 102 and the heat source heat exchanger 10 are provided.
3, the refrigerant is circulated through the compressor 104.

Inside the hot water storage tank 101, a first auxiliary heat exchanger 105 storing a hydrogen storage alloy and hydrogen is provided. A second auxiliary heat exchanger 106 storing different hydrogen storage alloys and hydrogen is provided, and the first auxiliary heat exchanger 105 and the second auxiliary heat exchanger 106 are airtightly connected.

During normal water heating operation, the pump 108 is driven with only the first valve 107 open, and the water in the hot water storage tank 101 is heated to the set temperature by the heat radiated by the tank heat exchanger 102. . At this time, the hydrogen storage alloy in the first auxiliary heat exchanger 105 releases hydrogen by heating, and the hydrogen storage alloy in the second auxiliary heat exchanger 106 stores the released hydrogen to generate reaction heat. The reaction heat is transferred to the fin 10 attached to the second auxiliary heat exchanger 106.
9 is emitted to the outside.

After heating to the set temperature, the compressor 104 is stopped, only the second valve 110 is opened, and in this state, the pump 108 is driven to flow the hot water in the hot water storage tank 101 through the second auxiliary heat exchanger 106. The hydrogen storage alloy in the second auxiliary heat exchanger 106 releases hydrogen, and the hydrogen storage alloy in the first auxiliary heat exchanger 105 stores the released hydrogen, and the accompanying reaction heat causes the hot water storage tank 10 Heat the water inside to an even higher temperature.

(Problem to be Solved by the Invention) However, in the case of the conventional example having such a configuration, during normal water heating operation, the reaction heat when storing hydrogen in the second auxiliary heat exchanger 106 is transferred to the outside. This has the disadvantage that thermal energy is wasted to the outside, lowering the coefficient of performance and being uneconomical.

In addition, in order to dissipate heat by storing hydrogen on the first auxiliary heat exchanger 105 side, the hot water storage tank 105
Since only the hot water inside is used, hydrogen can only be released in the second auxiliary heat exchanger 106 depending on the temperature of the hot water at the set temperature (low-temperature hot water), and the hot water storage tank 10
Although the water temperature inside 1 can be raised above the set temperature,
The drawback was that it could not be heated to very high temperatures.

The present invention was made in view of the above circumstances, and effectively utilizes the heat released during hydrogen storage in the second auxiliary heat exchanger to heat the refrigerant. In addition to efficiently heating up to the desired temperature, hydrogen is released in the second auxiliary heat exchanger at a temperature higher than the temperature set for the hot water storage tank. The purpose is to increase the temperature of hot water economically and to make it even hotter.

(Means for solving the problems) In order to achieve such an object, the present invention has the following features:
In the heat pump water heater using the hydrogen storage alloy described at the beginning, the second auxiliary heat exchanger 9
A heat exchange refrigerant circuit 1 connected to the
2, a state where the heat exchange refrigerant circuit 12 is connected between the discharge side of the compressor 8 and the inlet side of the tank heat exchanger 2, and a state where the heat exchange refrigerant circuit 12 is connected between the outlet side of the heat source heat exchanger 7. The configuration includes a switching mechanism 15 that switches between the state of connection and the suction side of the compressor 8.

(Function) With the above configuration, the present invention operates as follows during normal water heating operation and high temperature water heating operation.

During normal water heating operation, the switching mechanism 15 allows the heat exchange refrigerant circuit 12 to
is connected to the outlet side of the heat source heat exchanger 7 and the suction side of the compressor 8, and when the compressor 8 operates, the compressor 8
→ Tank heat exchanger 2 → Heat source heat exchanger 7 → Second auxiliary heat exchanger 9 → Compressor 8 and the refrigerant flows,
The low temperature refrigerant flows into the second auxiliary heat exchanger 9 to cool the second hydrogen storage alloy M2 built therein.
As a result, the first auxiliary heat exchanger 3 built-in
A moving differential pressure is generated between the hydrogen storage alloy M1 and the first hydrogen storage alloy M2 to move hydrogen, and the second hydrogen storage alloy
Hydrogen is stored by the hydrogen storage alloy M2, and the reaction heat generated during storage is given to the low-temperature refrigerant.

During high-temperature water heating operation, the switching mechanism 15 switches the heat exchange refrigerant circuit 12
is connected between the discharge side of the compressor 8 and the inlet side of the tank heat exchanger 2, and when the compressor 8 operates,
The refrigerant flows through the compressor 8 → the second auxiliary heat exchanger 9 → the tank heat exchanger 102 → the heat source heat exchanger 7 → the compressor 8, and the high temperature refrigerant flows through the second auxiliary heat exchanger 9. Built-in second hydrogen storage alloy M2
heat up. As a result, the second hydrogen storage alloy M
2, the hydrogen is transferred to the first auxiliary heat exchanger 3, and is stored in the first hydrogen storage alloy M1 built therein to generate reaction heat and raise the temperature of the hot water in the tank.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings. FIG. 1 is a piping configuration diagram of a heat pump type water heater of the present invention.

Reference numeral 1 denotes a hot water storage tank, in which a tank heat exchanger 2 for heating water is arranged at the bottom, and a first auxiliary heat exchanger 3 for heating the stored hot water during high-temperature water boiling operation is arranged at the top. . The first auxiliary heat exchanger 3 contains a first hydrogen storage alloy M1 and hydrogen. Reference numeral 4 denotes a hot water supply pipe, which is provided so that it is once led out from the top of the hot water storage tank 1, led to the first auxiliary heat exchanger 3, and then led out to the outside of the hot water storage tank 1. hot water pipe 4
A hot water tap 5 is attached to the end of the hot water tap 5, and a hot water pump 6 is attached to the front stage of the hot water tap 5. By opening the hot water tap 5 and driving the hot water pump 6, hot water in the hot water storage tank 1 is supplied. It is becoming possible to obtain it.

Reference numeral 7 denotes an outdoor heat exchanger as a heat exchanger for a heat source, which functions as an evaporator and serves as a heat source for the hot water storage tank 1. A compressor 8 circulates and flows the refrigerant from the tank heat exchanger 2 to the heat source heat exchanger 7.

Reference numeral 9 denotes a second auxiliary heat exchanger, which contains hydrogen and a second hydrogen storage alloy M2 whose temperature-hydrogen pressure characteristics are different from those of the first hydrogen storage alloy M1 as shown in FIG. The second auxiliary heat exchanger 9 is airtightly connected to the first auxiliary heat exchanger 3 through a hydrogen flow pipe 10, and the hydrogen flow pipe 10 has an on-off valve 11.
is provided.

12 is a heat exchange refrigerant circuit that is connected to the second auxiliary heat exchanger 9 and performs heat exchange;
Reference numeral 4 indicates first and second four-way switching valves, and the pair of four-way switching valves 13 and 14 connect the heat exchange refrigerant circuit 12 to the discharge side of the compressor 8 and the tank heat exchanger. A switching mechanism 15 is configured to switch between a state connected between the inlet side of the heat source heat exchanger 7 and a state connected between the outlet side of the heat source heat exchanger 7 and the suction side of the compressor 8.

In the figure, 16 is an expansion valve, 17 is an accumulator,
18 is a water supply pipe for supplying water to the hot water storage tank 1.

Next, the operation of this embodiment will be explained.

During normal water heating operation This normal water heating operation refers to low temperature water heating operation other than high temperature water heating operation.

By switching the first and second four-way switching valves 13 and 14 as shown by dotted lines and operating the compressor 8, the compressor 8 → first four-way switching valve 13 → second
Four-way switching valve 14 → Tank heat exchanger 2 → Expansion valve 16 → Heat source heat exchanger 7 → Second four-way switching valve 14
→Second auxiliary heat exchanger 9→First four-way switching valve 13→
The refrigerant flows from the accumulator 17 to the compressor 8, and the heat collected from the outside in the heat source heat exchanger 7 is released into the hot water storage tank 1 by the tank heat exchanger 2.
Heat the water to a set temperature of, for example, 50°C.

On the other hand, the second hydrogen storage alloy M2 of the second auxiliary heat exchanger 9 is caused by the low temperature refrigerant sucked into the compressor 8.
is cooled, and as it is heated, the first hydrogen storage alloy M1
The second hydrogen storage alloy M2 stores the hydrogen released from the hydrogen and transferred to the second auxiliary heat exchanger 9, and in the second auxiliary heat exchanger 9, the reaction heat generated during hydrogen storage is given to the low-temperature refrigerant.

During high-temperature water heating operation, the first and second four-way switching valves 13 and 14 are switched as shown by the solid line, and the compressor 8 is operated.
Auxiliary heat exchanger 9 → second four-way switching valve 14 → tank heat exchanger 2 → expansion valve 16 → heat source heat exchanger 7
→Second four-way switching valve 14→First four-way switching valve 13→
By flowing the refrigerant from the accumulator 17 to the compressor 8 and heating the hydrogen storage alloy M2 of the second auxiliary heat exchanger 9 with the high temperature refrigerant of, for example, 90°C discharged from the compressor 8, the hydrogen storage alloy M2
The hydrogen is released from the auxiliary heat exchanger 3, and this hydrogen is transferred to the first auxiliary heat exchanger 3.
1 and generates reaction heat of 90°C + α, raising the temperature of the hot water in the hot water supply pipe 4 to 90°C or higher.

The present invention can also be applied when an indoor heat exchanger is connected in parallel with the tank heat exchanger 2 to heat hot water at the same time as heating. It can also be applied when the exchanger is used as a heat source side heat exchanger and hot water is heated using cooling exhaust heat.

(Effects of the Invention) As described above, according to the present invention, since the heat released during hydrogen storage in the second auxiliary heat exchanger 9 is effectively used for heating the refrigerant, the coefficient of performance can be increased.
Heating to the set temperature in the hot water storage tank 1 can be performed efficiently and economically.

Furthermore, since hydrogen is released in the second auxiliary heat exchanger 9 using the high-temperature refrigerant discharged from the compressor 8, hydrogen can be released at a temperature higher than the temperature of the hot water in the hot water storage tank 1. The temperature of the hot water in the hot water storage tank 1 can be made even higher.

From these facts, for example, if the same heat capacity is obtained by the hot water storage tank 1, the temperature of the hot water can be increased, so the amount of hot water stored in the hot water storage tank 1 can be reduced, and the hot water storage tank 1 can be made smaller. , there is an advantage that hot water that does not reach high temperatures can be obtained in a short time by creating a state where hot water is obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a graph showing the characteristics of the hydrogen storage alloy used in the present invention, and FIG. 3 is a block diagram of a conventional example. 1 is a hot water storage tank, 2 is a tank heat exchanger, 3 is a first auxiliary heat exchanger, 7 is a heat source heat exchanger, 8 is a compressor, 9 is a second auxiliary heat exchanger, 12 is a refrigerant for heat exchange circuit, M1 is the first hydrogen storage alloy, M2 is the second hydrogen storage alloy.

Claims (1)

[Scope of Claims] 1. A tank heat exchanger 2 that heats the water in the hot water storage tank 1; a heat source heat exchanger 7; and a system from the tank heat exchanger 2 to the heat source heat exchanger 7. a compressor 8 that circulates and flows refrigerant; a first auxiliary heat exchanger 3 provided in the hot water storage tank 1 and containing a first hydrogen storage alloy M1 and hydrogen; A second hydrogen storage alloy M2 having temperature-hydrogen pressure characteristics different from that of the first hydrogen storage alloy M1, which is connected and provided outside the hot water storage tank 1, and a second auxiliary heat exchanger 9 containing hydrogen. A heat pump water heater using a hydrogen storage alloy comprising: a heat exchange refrigerant circuit 12 connected to the second auxiliary heat exchanger 9 to perform heat exchange; and a heat exchange refrigerant circuit 12 connected to the compressor 8. and the inlet side of the tank heat exchanger 2, and the outlet side of the heat source heat exchanger 7 and the suction side of the compressor 8. A heat pump type water heater using a hydrogen storage alloy and equipped with a switching mechanism 15 for switching.