JPH0120701B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigerant circuit, and more particularly to a refrigerant circuit capable of operating in a heating cycle using a heat pump cycle that absorbs heat using an outdoor heat exchanger and a forced refrigerant heating cycle using a burner or the like.

Conventionally, a cooling cycle consisting of a compressor, an outdoor heat exchanger, a capillary reach tube as a refrigerant expansion element, and an indoor heat exchanger is used as an air conditioning system, and a refrigerant heater such as a burner is added to the cooling cycle, which serves as a heat supply source to the refrigerant during heating operation. Many built-in ones are used.

However, the refrigerant circuit that constitutes such a conventional air-conditioning device has the following two major drawbacks.

That is, first, when the refrigerant is heated, it becomes a high-pressure, high-temperature gas, which causes a phenomenon in which the refrigerant moves to a low-temperature, low-pressure refrigerant circuit section. For this reason, refrigerant flows into the outdoor heat exchanger during heating, resulting in heat that should be transported indoors to be released outdoors. Therefore, as such a countermeasure, it is necessary to provide a solenoid valve or a check valve at the inlet of the outdoor heat exchanger to prevent refrigerant from flowing in, which complicates the structure.

In addition, even if the solenoid valve or check valve is installed, it is difficult to achieve a perfect sealing structure, and if the amount of accumulated water in the outdoor heat exchanger exceeds a specified value, it is necessary to expel it again. This requires a sequence to return this to the heating circuit, which complicates the equipment configuration, which has the disadvantage of not only increasing costs but also decreasing reliability.

Second, although it has a refrigerant circuit mechanism that can pump up heat by an outdoor heat exchanger during heat pump cycle operation, it is not possible to simultaneously use the heat pump cycle heating operation using this mechanism and the refrigerant heating cycle heating operation using the refrigerant heater. The disadvantage is that there is a waste of equipment.

Therefore, in view of the above-mentioned conventional circumstances, the present invention provides a heating cycle in which a heat pump cycle that absorbs heat by an outdoor heat exchanger and a forced refrigerant heating cycle by a refrigerant heating element are operated simultaneously. This provides a refrigerant circuit that can take measures to prevent heat from being released outdoors during refrigerant heating operation, and in the case of a refrigerant circuit that has a cooling cycle, can effectively utilize the heat pump cycle for the heating cycle.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

The figure is a refrigerant system diagram of a heating and cooling system equipped with a refrigerant circuit according to the present invention, and in the figure, 1 is a first compressor;
2 is a second compressor, 3 is a four-way valve, 4 is an outdoor heat exchanger, 5 is a capillary reach tube as a refrigerant expansion element, 6 is an indoor heat exchanger, 7 is a refrigerant heater as a refrigerant heating element, It is equipped with a 7a burner as a heat source. 8 and 9 are electromagnetic valves, respectively, and 10 and 11 are communication pipes.

Here, the first and second compressors 1 and 2 are arranged in parallel with the four-way valve 3, and the second compressor 2 has a solenoid valve 9 interposed in its suction side pipe. We are prepared.

The conduit between the second compressor 2 and the solenoid valve 9 and the conduit between the indoor heat exchanger 6 and the capillary reach tube 5 are interposed with a series circuit of a refrigerant heater 7 and a solenoid valve 8. connected.

The cooling cycle is constituted by a circuit in which the refrigerant circulates in the order of the two compressors 1 and 2, the four-way valve 3, the outdoor heat exchanger 4, the capillary reach tube 5, and the indoor heat exchanger 6. Compressor 1, four-way valve 3, indoor heat exchanger 6, capillary reach tube 5,
A heat pump cycle as a heating cycle is constituted by a circuit in which the refrigerant circulates in the order of the outdoor heat exchanger 4, and a circuit in which the refrigerant circulates in the order of the second compressor 2, the indoor heat exchanger 6, and the refrigerant heater 7. A refrigerant heating cycle is constituted, and a heating cycle is constituted by the heat pump cycle and the refrigerant heating cycle.

Note that the cooling cycle and the heating cycle are switched by a refrigerant circuit switching operation using the four-way valve 3.

The operation of the heating and cooling device having the above configuration will be explained.

First, in the cooling cycle, the solenoid valve 9 is opened,
Compressors 1 and 2 operate completely in parallel. On the other hand, the solenoid valve 8 is closed, and no refrigerant flows to the refrigerant heater 7. The high-temperature, high-pressure gas refrigerant compressed by the compressors 1 and 2 is sent to the outdoor heat exchanger 4 via the four-way valve 3, where the heat is released and becomes high-pressure liquid refrigerant. Furthermore, the high-pressure liquid refrigerant becomes a low-pressure, low-temperature liquid-gas mixed refrigerant through the capillary reach tube 5, absorbs heat in the indoor heat exchanger 6, evaporates, and gasifies.
The air is sucked into the compressors 1 and 2 via the air conditioner, and cooling operation continues. In this cooling cycle, the refrigerant flows as shown by the solid arrow in the figure. Next, in the heating cycle, the solenoid valve 9 is closed, and the compressors 1 and 2 are operated under different suction conditions. On the other hand, the solenoid valve 8 is opened, and the refrigerant heater 7 is activated by the operation of the second compressor 2.
With this circuit configuration, two refrigerant circuits are operated when viewed from the indoor heat exchanger 6, and the refrigerant flows as indicated by the broken line arrows in the figure.

That is, in one of the two refrigerant circuits, high pressure and high temperature gas compressed by the first compressor 1 is passed through the four-way valve 3.
By switching, the refrigerant flows to the indoor heat exchanger 6, releases heat indoors, and becomes a high-pressure liquid refrigerant. Then, it becomes a low-temperature, low-pressure liquid-gas mixed refrigerant in the capillary reach tube 5, obtains heat in the outdoor heat exchanger 4, evaporates, becomes a gas refrigerant, and is sucked into the compressor 1, forming a heat pump cycle. The other is the operation cycle of the refrigerant heating circuit, in which the high-temperature, high-pressure gas refrigerant sucked into the second compressor 2 is sent to the indoor heat exchanger 6 via the four-way valve 3, as in the previous cycle. The refrigerant heat is released into the room, becomes a high-pressure liquid refrigerant, passes through the solenoid valve 8, is heated by the refrigerant heater 7, becomes a gas refrigerant, and is sucked into the compressor 2, forming a refrigerant heating cycle.

In this case, the second compressor 2 acts as a pump.

In such a heating cycle, the heat pump cycle and the operation cycle of the refrigerant heating circuit can also be selectively used.

In this case, the compressors 1 and 2 may be selectively operated with the solenoid valve 8 open and the solenoid valve 9 closed.

According to this configuration, by operating the two compressors 1 and 2 separately by operating the solenoid valves 8 and 9 during heating,
A heat pump cycle is used when a refrigerant heating cycle with a refrigerant heater 7 and a heat pump cycle with an outdoor heat exchanger 4 can be operated simultaneously in one refrigerant circuit to obtain heat from outside air. handles much of the heating load, and when the outside temperature drops and it becomes difficult to remove heat, the refrigerant heating cycle is heavily weighted, making it possible to use the heat pump cycle effectively, enabling powerful heating that is less affected by the outside temperature. becomes.

In addition, when the outdoor air conditions become difficult to absorb heat, the outdoor heat exchanger 4 is maintained at a low temperature and pressure by the action of the heat pump cycle, and the high temperature and high pressure refrigerant heated by the refrigerant heater 7 is returned to the outside. Since the structure is such that heat does not enter the heat exchanger 4, heat is not released in the outdoor heat exchanger 4 as in the conventional case, and therefore, unlike in the conventional case, high-temperature and high-pressure gas does not enter the outdoor heat exchanger 4 when using a refrigerant heater. There is no need to add any structure to prevent intrusion into the outdoor heat exchanger, the structure does not become complicated, and reliability does not deteriorate.

In addition, in such a configuration, during the heating cycle operation, only the heat pump cycle is operated when sufficient heat can be obtained from the outside air, and when the outside temperature drops and it becomes difficult to remove the heat, the refrigerant heating is performed. It is also easy to use because it is possible to operate only the operating cycle of the circuit. Moreover, the first and second compressors 1 and 2 are used together for heating and cooling, and in particular, during cooling, both compressors 1 and 2 are operated in parallel, so the capacities of both compressors 1 and 2 are combined. It can be effective.

As explained above, the present invention has a configuration in which the heat pump cycle using the outdoor heat exchanger and the refrigerant heating cycle using the refrigerant heater are operated simultaneously by separate operation of two compressors. Since there is no need to take measures for heat dissipation in the outdoor heat exchanger, high costs can be prevented, and the device can be made highly reliable. can make effective use of the heat pump cycle. In addition, in the heating cycle, the heat pump cycle and the operation cycle of the refrigerant heating circuit can be selectively used depending on the outside temperature, etc., which provides excellent usability. In particular, since the first and second compressors are provided and used for both heating and cooling, and both compressors are operated in parallel during cooling, the compression capacity can be increased.

[Brief explanation of drawings]

The figure is a refrigerant system diagram of a heating and cooling device to which the refrigerant circuit according to the present invention is applied. 1...First compressor, 2...Second compressor, 3
... Four-way valve, 4 ... Outdoor heat exchanger, 5 ... Capillary reach tube, 6 ... Indoor heat exchanger, 7 ... Refrigerant heater, 8, 9 ... Solenoid valve, 10, 11 ... Communication pipe .

Claims (1)

[Claims] 1 A heat pump cycle configuration circuit formed by interconnecting a first compressor, an indoor heat exchanger, a refrigerant expansion element, and an outdoor heat exchanger, a second compressor, and the indoor heat exchanger. and a refrigerant heating element, the first and second compressors are arranged in parallel with the four-way valve, and the second A solenoid valve is interposed in the suction side conduit of the compressor, and the refrigerant heating element is provided in the conduit between the compressor and the solenoid valve and the conduit between the indoor heat exchanger and the refrigerant expansion element. A refrigerant circuit characterized in that the refrigerant circuit is constructed by interposing and connecting a series circuit of a different electromagnetic valve to the electromagnetic valve.