JPH04270875A - Air conditioner - Google Patents

Abstract

PURPOSE:To melt frost, remaining still after consuming all of accumulated heat source, when defrosting operation is effected utilizing the accumulated heat. CONSTITUTION:In a heat pump type air conditioner equipped with a heat accumulating heat exchanger, heat is provided from the heat accumulating heat exchanger 4 after melting frost, adhered to an evaporator 6, during defrosting and heating operation utilizing accumulated heat. When accumulated heat source is insufficient, an on-off valve 10 is opened to switch a circuit into hot-gas bypass system whereby the defrosting operation is finished after melting the frost, adhered to the evaporator 6, perfectly.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump type air conditioner improved in terms of defrosting.

0002

[Prior Art] FIG. 5 shows, for example, Japanese Patent Application Laid-Open No. 62-175559
1 is a refrigerant circuit diagram of a conventional heat pump type air conditioner shown in the issue, in which 1 is a compressor, 2 is a condenser, and 3
is a first on-off valve, 4 is a thermal storage heat exchanger, 5 is a first pressure reducing device,
6 is an evaporator, 7 is a second on-off valve, 8 is a second pressure reducing device, 9 is a third on-off valve, 10 is a fourth on-off valve, 12 is a defrosting sensor, 1
4 is a control device.

Next, the operation of the air conditioner will be explained based on FIG. 5. First, during heating operation, the first and third on-off valves 3 and 9 are opened and the second and fourth on-off valves 7 and 10 are closed, and the refrigerant that has exited the condenser 2 passes through the regenerative heat exchanger 4 and 1 from the pressure reducing device 5 to the evaporator 6, and then to the compressor 1 via the third on-off valve 9.
By returning to
, the fourth on-off valves 7, 10 open, the first and third on-off valves 3,
9 is closed, and the refrigerant leaving the condenser 2 passes through the second on-off valve 7 and the second pressure reducing device 8 to the evaporator, and further passes through the first pressure reducing device 5 to the heat storage heat exchanger 4 where the refrigerant is transferred to the heat storage material. is supplied with
By returning to the compressor 1 via the fourth on-off valve 10, heating and defrosting of the evaporator 6 can be performed simultaneously using the heat storage material as a heat source, and when the defrost sensor 12 reaches a certain temperature, for example, 3° C. or higher, If this happens, end the defrosting operation.

0004

[Problem to be Solved by the Invention] Since the conventional air conditioner is constructed as described above, if the heat source of the heat storage material is used up before the frost completely melts during the defrosting operation, residual frost may occur. There was a problem with this.

[0005] This invention was made to solve the above-mentioned problems, and even if the heat source of the heat storage material is completely used up during the defrosting operation, the defrosting operation can be completed without any residual frost. The purpose is to obtain an air conditioner that can.

[0006]

[Means for Solving the Problems] In the air conditioner according to the present invention, when the heat source of the heat storage material is used up before the frost completely melts during defrosting operation, the circuit is switched off to the hot gas bypass method. It is configured so that it can be replaced.

[0007]

[Operation] The air conditioner according to the present invention can melt all the frost and end the defrosting operation without leaving any residual frost even if the heat source of the heat storage material is used up during the defrosting operation using heat storage.

[0008]

Embodiments <First Embodiment> An embodiment of the present invention will be described below with reference to the drawings. In the figure, 1 is a compressor, 2 is a condenser, 3 is a first on-off valve, 4 is a heat storage and heat storage exchanger built in a heat storage tank together with a heat storage material, 5 is a first pressure reducing device, and 6 is an evaporator. These refrigerant circuits are connected in series to form a first refrigerant circuit. Reference numeral 7 indicates a second on-off valve, and reference numeral 8 indicates a second pressure reducing device, which are successively connected in series to form a second refrigerant circuit in parallel with the first refrigerant circuit. 9 is the third
The first and second refrigerant circuits are connected to the evaporator 6 by an on-off valve.
The part that joins on the outlet side of the compressor 1 is connected to the suction side of the compressor 1. A fourth on-off valve 10 is connected to a third refrigerant circuit between the first on-off valve 3 and the storage heat exchanger 4 and between the third on-off valve 9 and the compressor 1. Reference numeral 11 denotes a fifth on-off valve, which connects the discharge side of the compressor 1, the first pressure reducing device 5, and the evaporator 6.
The hot gas bypass circuit is connected to the fourth refrigerant circuit between the hot gas bypass circuit and the hot gas bypass circuit.

12 is a defrosting sensor installed near the outlet of the evaporator 6, and 13 is a heat storage sensor 14 installed in the heat storage heat exchanger 4, which is a control device, and is configured as shown in the system configuration block diagram of FIG. has been done. That is, the microcomputer 15 consists of a central processing unit 16, an input circuit 17, and an output circuit 18, the input circuit is connected to the defrosting sensor 12 and the heat storage sensor 13, and the output circuit is connected to the first on-off valve 3 and the second on-off valve. The valve 7, the third on-off valve 9, the fourth on-off valve 10, and the fifth on-off valve 11 are connected, respectively. 19 is a defrosting operation switch.

Next, the operation of this embodiment configured as described above will be explained based on the flowcharts of FIGS. 1 and 4 showing the flow of the defrosting operation. First, during heating operation, it operates in the same way as before, and if frost has formed, defrosting heating operation using heat storage is performed, that is, the second and fourth on-off valves 7 and 10 open,
The first, third, and fifth on-off valves 3, 9, and 11 are closed. The high temperature and high pressure refrigerant gas coming out of the compressor 1 is sent to the condenser 2.
The frost adhering to the evaporator 6 is melted by the gas-liquid two-phase refrigerant that passes through the second on-off valve 7 and the second pressure reducing device 8, and then the refrigerant liquid passes through the first pressure reducing device 5. It evaporates in the storage heat exchanger 4 and becomes refrigerant gas, which passes through the fourth on-off valve 10 and returns to the compressor 1. At this time, defrosting is terminated when the defrost sensor 12 reaches a certain temperature, for example, 3°C or higher, but before the defrost sensor 12 reaches a certain temperature, the heat storage sensor 1
When the temperature drops below 3°C, there is no longer a heat source to melt the frost, and if this operation continues, it will cause frost to form again. Therefore, defrosting is not completed,
In addition, if the thermal storage heat source is exhausted, switch to the hot gas bypass method. That is, the third and fifth on-off valves 9 and 11
is opened and the first, second, and fourth on-off valves 3, 7, and 10 are closed, and the high-temperature, high-pressure refrigerant gas discharged from the compressor 1 is directly sent to the evaporator 6 for defrosting. In this way, the defrosting operation is terminated when the defrosting sensor 12 reaches 3° C. or higher.

<Second Embodiment> In the above embodiment, during the defrosting operation, the frost adhering to the evaporator 6 is melted and then the storage heat exchanger 4 is
As shown in Figure 2, the heat storage heat exchanger 4
A circuit that melts the frost in the evaporator 6 after receiving heat from the evaporator 6 also has the same effect as described above.

0012

[Effects of the Invention] As described above, according to the present invention, during defrosting operation, if the heat source of the heat storage material disappears before the frost completely melts, the circuit is switched to the conventional hot gas bypass method. Therefore, there is an effect that the defrosting operation can be ended by melting all the frost in any case.

[Brief explanation of the drawing]

FIG. 1 is a refrigerant circuit diagram showing an air conditioner according to an embodiment of the present invention.

FIG. 2 is a refrigerant circuit diagram corresponding to FIG. 1 showing another embodiment of the present invention.

FIG. 3 is a flowchart of an air conditioner according to an embodiment of the present invention.

FIG. 4 is a system configuration block diagram of an air conditioner according to an embodiment of the present invention.

FIG. 5 is a refrigerant circuit diagram showing a conventional air conditioner.

[Explanation of symbols]

1 Compressor 2 Condenser 3 First on-off valve 4　Regenerative heat exchanger 5 First pressure reducing device 6 Evaporator 11 Fifth on-off valve

Claims (1)

[Claims] Claim 1: A heat storage device comprising a compressor, a condenser, a first pressure reducing device, and an evaporator in a sequential circuit, and a first on-off valve and a heat storage material built into a heat storage tank between the condenser and the evaporator. In a heat pump air conditioner including a heat exchanger, a first pressure reducing device, and an evaporator in this order, a fifth on-off valve is connected between the discharge side of the compressor, the evaporator, and the first pressure reducing device. An air conditioner characterized in that a hot gas bypass circuit is provided, and when defrosting, a defrosting heating operation using heat storage is performed, and when the heat storage heat source is insufficient, switching to a hot gas bypass method is performed.