JPH0125981B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air-conditioning, heating, and water-heating system, and its main purpose is to use an internal combustion engine to drive a compressor in a heat pump circuit to perform cooling or heating, and to operate the internal combustion engine during heating operation. To provide an air-conditioning/heating water supply device which improves thermal efficiency by fully utilizing the exhaust heat of the engine for heating, and by sufficiently recovering the exhaust heat of an internal combustion engine and the heat radiated from a heat pump circuit when supplying hot water.

The present invention provides: a heat pump circuit that circulates a medium using a compressor to achieve a cooling or heating state; an internal combustion engine that drives the compressor of the heat pump circuit; and a heat medium that is heated by exhaust heat of the internal combustion engine. a high-temperature heat exchanger; a medium-high-temperature heating coil that is installed in the high-temperature heat exchanger and can be freely connected between an air conditioner and a compressor that function as a condenser during the heating operation of the heat pump; a heat dissipation coil that can be connected by bypassing the heat exchanger and functions as a condenser during hot water supply; a hot water storage tank containing the heat dissipation coil and storing relatively low-temperature hot water; the hot water storage tank and the high-temperature heat exchanger; This is an air-conditioning/heating water supply device characterized by comprising: hot water circulation circuits that are connected to form a closed circuit; and means for extracting hot water from part of the hot water circulation circuit.

In a preferred embodiment, the hot water circulation circuit includes a pump that is driven so that the temperature difference between the heat medium in the high-temperature heat exchanger and the hot water in the hot water storage tank is a predetermined constant value. do.

In a preferred embodiment, a medium low temperature heating heat exchanger is provided between the compressor of the heat pump circuit and the evaporator during heating operation, and the medium low temperature heating heat exchanger forms a closed circuit with the hot water storage tank. It is characterized by being connected as follows.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram of an embodiment of the present invention in a cooling operation state, and in FIG. 1, unused pipes are indicated by broken lines. This air conditioning/heating water supply system includes a heat pump circuit 2 that circulates a medium in a closed circuit using a compressor 1 to achieve cooling or heating, and an internal combustion engine 3 for driving the compressor 1.
A high-temperature heat exchanger 4 for using the exhaust heat of the internal combustion engine 3 to heat hot water or to heat the medium of the heat pump circuit 2 in a heating operation state, a hot water storage tank 5 for storing hot water at a relatively low temperature, and a hot water storage tank 5 for storing hot water at a relatively low temperature. A hot water circulation circuit 6 circulates water between a high temperature heat exchanger 4 and a hot water storage tank 5.
including.

The heat pump circuit 2 includes a compressor 1, an air conditioner 7 that is placed inside a room to be air-conditioned and functions as an evaporator during cooling operation and a condenser during heating operation, an expansion valve 8, and an expansion valve 8 that is installed outdoors and functions as a cooling operation. A heat exchanger 9 that sometimes functions as a condenser and as an evaporator during heating operations, and a four-way valve 10 that switches the flow of the medium in the closed circuit in the forward and reverse directions.
including. One end of a pipe line 12 is connected via a three-way valve 13 to a pipe line 11 connecting the four-way valve 10 and the air conditioner 7 near the four-way valve 10 . This conduit 12
is equipped with a medium high temperature heating coil 14 for heating the medium at a relatively high temperature, and the other end is connected to the pipe line 11 near the air conditioner 7. Further, one end portion of a pipe line 15 is connected to the pipe line 11 between the four-way valve 10 and the three-way valve 13 via a three-way valve 16.
This conduit 15 is equipped with a heat radiation coil 17,
The other end is connected via a three-way valve 19 to the middle of a conduit 18 that connects the air conditioner 7 and the expansion valve 8 .
Further, a medium low temperature heating heat exchanger 21 for heating the medium at a relatively low temperature is provided in the middle of the pipe line 20 connecting the four-way valve 10 and the heat exchanger 9.

The high-temperature heat exchanger 4 includes a medium-high-temperature heating coil 14 in a sealed casing 22 filled with a heat medium;
A coil 23, a heat radiation section 25, and a coil 32 are provided. A jacket 3a for cooling the main body of the internal combustion engine 3 and a coil 23 are connected to form a closed circuit, and cooling water is circulated within the closed circuit. Therefore, the cooling water whose temperature has risen by cooling the internal combustion engine main body with the jacket 3a radiates heat through the coil 23 in the high-temperature heat exchanger 4, thereby heating the heat medium in the high-temperature heat exchanger 4. Note that a cooler 26 such as a cooling fan is provided in the middle of the line returning from the coil 23 to the jacket 3a in order to prevent the cooling water from returning to the jacket 3a at a high temperature due to insufficient heat dissipation in the coil 23. It will be done. The duct 24 that guides the exhaust gas of the internal combustion engine 3 is provided with a heat radiating section 25 in the middle thereof, so that the sensible heat of the high temperature exhaust gas is given from the heat radiating section 25 to the heat medium in the high temperature heat exchanger 4. In addition, in order to prevent the temperature of the heat medium in the high-temperature heat exchanger 4 from rising excessively, a bypass duct 27 is provided in the middle of the duct 24 to bypass the heat radiation section 25. An opening/closing damper 28 is provided in the middle of the duct 27.

The hot water storage tank 5 has a conduit 2 for supplying hot water.
9 is connected. Inside this hot water storage tank 5, there is a conduit 15.
The above-mentioned heat dissipation coil 17 provided in the middle is provided. Further, a coil 30 is provided in the hot water storage tank 5, and this coil 30 and the medium low temperature heating heat exchanger 21 in the heat pump circuit 2 are connected to form a closed circuit. A medium circulation pump 31 is provided inside.

The hot water circulation circuit 6 is formed by interconnecting the hot water storage tank 5 and the coil 32 in the high-temperature heat exchanger 4 through pipes 33 and 34, and a pump 35 is provided in the middle of the pipe 33. Further, branch pipes 38 and 39 are provided with valves 36 and 37 in the middle of the pipes 33 and 34, respectively.
are connected to each other, and both branch pipes 38, 3
9 is commonly connected to the hot water supply pipe 40.

The high-temperature heat exchanger 4 and the hot water storage tank 5 are provided with temperature detectors 50 and 51, respectively, and the detected values of the temperature detectors 50 and 51 are input to the controller 52, respectively. The controller 52 drives the pump 35 so that the difference between the input temperature detection values becomes a predetermined value. That is, hot water is circulated within the hot water circulation circuit 6 so that the heat medium within the high temperature heat exchanger 4 does not reach an abnormally high temperature. Thereby, the temperature of the hot water supply in the hot water storage tank 5 is maintained at, for example, about 45°C, and the temperature of the heat medium in the high-temperature heat exchanger 4 is maintained at, for example, about 90°C. Note that there is a bypass pipe 4 in the middle of the pipe 33 that bypasses the pump 35.
1 is provided, and a check valve 42 is provided in the middle of this bypass pipe line 41.

In the air-conditioning/heating/water supply apparatus configured as described above, the operation in the cooling operation state will first be described. In this cooling operation state, the four-way valve 10 and the three-way valves 13, 16, 19 in the heat pump circuit 2 are switched as shown in FIG. 1, and the internal combustion engine 3 is driven. As a result, the compressor 1 operates, and the medium is transferred in the heat pump circuit 2 from the compressor 1 to the four-way valve 10 to the medium low temperature heating heat exchanger 21 to the heat exchanger 9 to the expansion valve 8 to the three-way valve 19 to the air conditioner. 7→three-way valve 13→three-way valve 16→four-way valve 10→compressor 1.

The compressor 1 compresses the vapor of the medium to convert it into relatively high-temperature superheated vapor and supplies it to the heat exchanger 9 . This heat exchanger 9 functions as a condenser, and the superheated steam is cooled and condensed in the heat exchanger 9. While passing through the expansion valve 8, the condensed medium evaporates into low-temperature, low-pressure wet steam and enters the air conditioner 7. Since this wet steam has a lower temperature than the temperature of the room to be air-conditioned, the medium in the air conditioner 7 absorbs heat from the surroundings and evaporates. The medium evaporated in the air conditioner 7 returns to the compressor 1 and the aforementioned process is repeated. In this way, cooling is achieved by the medium in the air conditioner 7 removing heat from the surroundings.

When the pump 31 is driven in this cooling operation state, the medium low-temperature heat exchanger 21 functions as a cooler, and the medium superheated vapor from the compressor 1 is cooled. The amount of heat taken from the medium superheated steam is used to heat the hot water in the hot water storage tank 5, and the temperature of the hot water in the hot water storage tank 5 is raised to, for example, about 45°C. Note that if the temperature of the hot water in the hot water storage tank 5 has already risen to about 45° C., the drive of the pump 31 may be stopped.

Next, the operation in the heating operation state will be explained with reference to FIG. In the heating state,
The four-way valve 10 and the three-way valves 13, 16, and 19 are switched as shown in FIG. Thereby, the medium circulates within the heat pump circuit 2 in the opposite direction to the cooling operation state described above. Thereby, the air conditioner 7 functions as a condenser, and the condenser radiates heat into the room to be air-conditioned. Moreover, before the medium is supplied from the compressor 1 to the air conditioner 7, the medium is heated by exchanging heat with a heat medium of about 90° C. in the medium high-temperature heating coil 14 in the high-temperature heat exchanger 4. Furthermore, before entering the compressor 1, the medium is heated by indirectly exchanging heat with hot water at a relatively low temperature (approximately 45° C.) in the hot water storage tank 5 in the medium low-temperature heating heat exchanger 21. Therefore, in addition to the amount of heat pumped up by the heat exchanger 9 functioning as an evaporator, the amount of heat given from the exhaust heat of the internal combustion engine 3 and the hot water supply is given to the medium. Therefore, the amount of heat radiated by the air conditioner 7 increases, and sufficient heating is achieved.

Note that the switching state of the three-way valve 13 may be changed as shown in FIG. 3, and the heat pump circuit 2 may be operated in the same manner as a normal heat pump, so that heating can be performed only by the amount of heat pumped up by the heat exchanger 9.

The operation in the hot water supplying state will be explained with reference to FIG. In the hot water supply operation state, the four-way valve 10 and the three-way valve 1 in the heat pump circuit 2
3, 16, and 19 are switched as shown in FIG. 4, so that the coil 17 functions as a condenser instead of the air conditioner 7. Therefore, the heat of medium condensation of the heat pump circuit 2 is radiated in the heat radiation coil 17, and the hot water in the hot water storage tank 5 is heated to, for example, about 45°C. Further, the heat medium in the high temperature heat exchanger 4 is, for example, about 90%
It is heated to about ℃. Furthermore, hot water can freely flow in the pipe line 33 via the bypass pipe line 41. Therefore, when the valves 36 and 37 are opened,
Hot water at a relatively low temperature (approximately 45° C.) from the conduit 33 and hot water at a relatively high temperature (approximately 90° C.) from the conduit 34 are supplied to the hot water pipe 40 . Therefore, by adjusting the opening degrees of the valves 36 and 37 and selecting the flow rate ratio of relatively low-temperature hot water and relatively high-temperature hot water, the temperature of the hot water supplied from the hot water pipe 40 can be adjusted. can be adjusted freely.

In addition, in the hot water circulation circuit 6, the pump 35
As described above, the drive thereof is controlled by the controller 52, whereby the temperature difference between the heat medium in the high temperature heat exchanger 4 and the hot water in the hot water storage tank 5 is maintained approximately constant.

As described above, according to the present invention, the exhaust heat of the internal combustion engine is stored in the high-temperature heat exchanger, the heat released from the heat pump circuit is stored in the hot water storage tank, and the medium of the heat pump circuit is used by the exhaust heat of the internal combustion engine during heating operation. Since it is heated, the heating effect can be further improved. In addition, since the hot water is circulated between the high temperature heat exchanger and the hot water storage tank and heated, it is possible to fully utilize the exhaust heat of the internal combustion engine and the heat released from the heat pump circuit, thus improving thermal efficiency. .

[Brief explanation of drawings]

Figure 1 is a system diagram of an embodiment of the present invention in a cooling operation state, Figure 2 is a system diagram in a heating operation state, and Figure 3 is a system diagram in a heating operation state when the medium is not heated by the exhaust heat of the internal combustion engine. FIG. 4 is a system diagram in the hot water supply operation state. 1...Compressor, 2...Heat pump circuit, 3...
... Internal combustion engine, 4 ... High temperature heat exchanger, 5 ... Hot water storage tank, 6 ... Hot water circulation circuit, 7 ... Air conditioner, 9 ...
... Heat exchanger, 14 ... Coil for medium high temperature heating, 1
7... Coil for heat radiation, 21... Heat exchanger for medium low temperature heating, 40... Hot water pipe.

Claims (1)

[Scope of Claims] 1. A heat pump circuit that circulates a medium using a compressor to achieve a cooling or heating state; an internal combustion engine that drives the compressor of the heat pump circuit; a high-temperature heat exchanger that heats a medium; a coil for medium high-temperature heating that is provided in the high-temperature heat exchanger and can be freely connected between an air conditioner and a compressor that functions as a condenser during the heating operation of the heat pump; , a heat dissipation coil that can be connected by bypassing the air conditioner and functions as a condenser during hot water supply; a hot water storage tank containing the heat dissipation coil and storing relatively low temperature hot water; the hot water storage tank and high temperature heat; An air-conditioning/heating water supply device comprising: a hot water circulation circuit that connects exchangers to form a closed circuit; and means for extracting hot water from a part of the hot water circulation circuit. 2. The hot water circulation circuit includes a pump that is driven so that the temperature difference between the heat medium in the high-temperature heat exchanger and the hot water in the hot water storage tank is a predetermined constant value. The air conditioning/heating and hot water supply device according to scope 1. 3 A medium low temperature heating heat exchanger is provided between the compressor of the heat pump circuit and the evaporator during heating operation, and this medium low temperature heating heat exchanger is connected to the hot water storage tank to form a closed circuit. An air-conditioning/heating/hot water supply apparatus according to claim 1 or 2, characterized in that: