JPH086974B2 - Air conditioner - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling and heating apparatus that operates in a vapor compression system during cooling and operates in a non-powered heat transfer medium system during heating.

2. Description of the Related Art The conventional heat pump heating device has a drawback that the evaporation temperature of the refrigerant decreases as the outside air temperature decreases, and as a result, the refrigerant circulation amount to the condenser decreases and the heating capacity decreases. In order to supplement this heating capacity, there is known a method of heating the refrigerant by combustion heat instead of absorbing the refrigerant from the atmospheric heat during heating to improve the heating capacity.In this case, in addition to the conventional outdoor heat exchanger, Further, since a refrigerant heater is required and the refrigerant is conveyed by the compressor, there is a problem in terms of initial cost and running cost. So the second
The outdoor heat exchanger as shown in the figure is used as a condenser during cooling operation and as a heater during heating operation.The cooling operation is performed by the vapor compression type, and the heating operation is performed by the non-powered heat medium transfer method, reducing the initial cost and running cost of the system. It is possible to think of a device for achieving this. 1 is a compressor, 2 is a first check valve, 3 is an outdoor heat exchanger that serves as a condenser during cooling, and a refrigerant heater during heating,
Reference numeral 4 is a decompression device, 5 is a first electromagnetic valve, 6 is an indoor heat exchanger, 7 is a second electromagnetic valve, and 8 is an accumulator, which constitutes a refrigeration cycle during cooling operation. Reference numeral 9 is a second check valve, 10 is a liquid receiver, 11 is a third check valve, 12 is an opening / closing valve, and 13 is a third solenoid valve.

In the above configuration, the compressor 1 does not operate during heating operation, and the refrigerant evaporated in the outdoor heat exchanger 3 serving as a refrigerant heater is the third solenoid valve 13
The refrigerant that has been condensed and liquefied by being pressure-fed to the indoor heat exchanger 6 flows into the liquid receiver 10. During this heating operation, the first solenoid valve 5 and the second solenoid valve 7 are closed. When the liquid refrigerant accumulates in the liquid receiver 10, the on-off valve 12 opens and the liquid receiver 10 arranged above the outdoor heat exchanger 3 transfers the liquid refrigerant by its own weight to the outdoor heat exchanger 3 which is a refrigerant heater. Inflow. At this time, the outdoor heat exchanger 3
The pressure of the liquid receiver 10 is equalized, and the liquid refrigerant does not flow into the liquid receiver 10 from the indoor heat exchanger 6. Next, when the liquid refrigerant in the liquid receiver 10 runs out, the on-off valve closes and the condensed liquid refrigerant accumulates in the liquid receiver 10 again. At this time, the liquid is received by the second check valve 11.
The liquid refrigerant flowing into 10 does not flow into the outdoor heat exchanger 3. As described above, by repeatedly opening and closing the on-off valve 12, the liquid refrigerant is intermittently supplied from the liquid receiver 10 to the outdoor heat exchanger 3 which is a refrigerant heater, and the refrigerant evaporated and gasified in the outdoor heat exchanger 3 is discharged. The cycle in which the heat is sent to the indoor heat exchanger 6 is repeated during the heating operation.

Problems to be Solved by the Invention However, in the configuration as shown in FIG.
Although the check valve 2 and the second electromagnetic valve 7 are in the closed state, the refrigerant gradually accumulates in the compressor 1 due to refrigerant leakage from the first check valve 2 and the second electromagnetic valve 7 when operated for a long time. However, there is a problem that the refrigerant in the heating operation cycle decreases, the refrigerant temperature of the outdoor heat exchanger 3 which is a refrigerant heater rises, the thermal stability of the refrigerant decreases, and the reliability of the system decreases.

The present invention solves such a conventional problem, and utilizes the timing when the room temperature reaches the set value of the indoor temperature detector during heating and the heating operation is stopped, and when the pressure in the heating cycle drops, it accumulates in the compressor. The purpose of this is to improve the reliability of the system by returning the refrigerant to the heating cycle by operating the compressor with the solenoid valve on the compressor intake side closed.

Means for Solving the Problems In order to solve the above problems, the cooling and heating apparatus of the present invention includes a compressor, a first check valve, a refrigerant heater during heating, an outdoor heat exchanger that serves as a condenser during cooling, and a decompression device. , A first solenoid valve, an indoor heat exchanger, a second solenoid valve, an accumulator, and a second check valve, a liquid receiver, and a third check valve connected in parallel with the pressure reducing device and the first solenoid valve. A check valve, a pressure equalizing pipe having an opening / closing valve between the liquid receiver and the first check valve and the outdoor heat exchanger, a portion between the first check valve and the opening / closing valve, and the second Combustion of the outdoor heat exchanger of the refrigerant heater is stopped when the heating pipe having a third electromagnetic valve between the electromagnetic valve and the indoor heat exchanger and the indoor temperature detector reaches a set temperature after the start of heating operation. A control device for performing a compressor operation (hereinafter referred to as pump down operation) for a certain period of time with the second solenoid valve closed. It is equipped with a table.

Effect According to the present invention, the heating cycle and the compressor are separated by the second electromagnetic valve and the first check valve during the heating operation by the above-described configuration, but the leakage from the second electromagnetic valve and the first check valve Due to this, the refrigerant in the heating cycle gradually stops and accumulates in the compressor, but when the room temperature reaches the set temperature of the indoor temperature detector, the combustion of the outdoor heat exchanger, which is the refrigerant heater, is stopped, and the pressure in the heating cycle becomes Since the control device that stops the compressor pump down for a certain period of time by using the lowered timing is installed, the compressor pump down power consumption is low and the refrigerant heat exchanger's outdoor heat exchange due to the decrease of the refrigerant during the heating cycle. The thermal stability of the refrigerant in the container can be prevented from lowering and the reliability of the system can be improved.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings. The same parts as those in FIG. 2 are designated by the same reference numerals.

In FIG. 1, 1 is a compressor, 2 is a first check valve, 3 is an outdoor heat exchanger that serves as a condenser during cooling, and a refrigerant heater during heating,
4 is a decompression device, 5 is a first solenoid valve, 6 is an indoor heat exchanger, 7
Is a second solenoid valve, and 8 is an accumulator, which constitutes a refrigeration cycle. Reference numeral 9 is a second check valve that is connected in the forward direction from the refrigeration cycle to a liquid receiver 10 disposed at a position higher than the outdoor heat exchanger 3, and 11 is from the liquid receiver 10 to the refrigeration cycle. It is a third check valve connected in the forward direction and is arranged in parallel with the pressure reducing device 4 and the first electromagnetic valve 5. 14 is a pressure equalizing pipe having the liquid receiver 10 and an opening / closing valve 12 arranged between the first check valve 2 and the outdoor heat exchanger 3,
15 is between the first check valve 2 and the on-off valve 12, and the second
A heating pipe having a third solenoid valve 13 between the solenoid valve 7 and the indoor heat exchanger 6, 16 is an indoor temperature detector, and 17 is a refrigerant heater when the room temperature reaches the set value of the indoor temperature detector 16. This is a control device that closes the combustion valve 18 and performs a pump-down operation of the compressor 1 for a predetermined time.

In the above configuration, during the cooling operation, the first solenoid valve 5 and the second solenoid valve 7 are open, the on-off valve 12 and the third solenoid valve are closed, and the high temperature and high pressure refrigerant of the compressor 1 is the outdoor heat exchanger. It is condensed and liquefied at 3, decompressed and expanded at the decompression device 4, evaporated and gasified at the indoor heat exchanger 6, and returned to the compressor 1 through the accumulator 8. At this time, the liquid refrigerant does not flow into the liquid receiver 19 due to the second check valve 11.
On the other hand, during the heating operation, the first solenoid valve 5 and the second solenoid valve 7 are closed,
The third solenoid valve 13 is opened, and the opening / closing valve 12 repeats the opening / closing operation. The refrigerant vaporized and gasified by the outdoor heat exchanger 3 which serves as a refrigerant heater during the heating operation passes through the heating pipeline 15 and the indoor heat exchanger 6
And is condensed and liquefied. At this time, if the on-off valve 12 is closed, the condensed and liquefied refrigerant flows into the liquid receiver 10 arranged at a position higher than the outdoor heat exchanger 3, and the liquid refrigerant pools in the liquid receiver 10. When the operation is completed, the on-off valve 12 opens and the receiver 10
The liquid refrigerant inside flows into the outdoor heat exchanger 3, which is a refrigerant heater, by its own weight. When the on-off valve 12 is open, the condensed liquid refrigerant does not flow into the liquid receiver 10. The above operation is repeated during the heating operation, and the gas refrigerant is pumped to the outdoor heat exchanger 3 which is a refrigerant heater or intermittently to the indoor heat exchanger 6 which is supplied from the liquid receiver 10. is there. During this heating operation, the compressor 1 is stopped and is separated from the heating cycle by the first check valve 2 and the second electromagnetic valve 7, but due to their leakage, the amount of refrigerant in the heating cycle is gradually increased. Decrease, but indoor temperature detector
When the room temperature reaches the set value of 16, the control device 17 closes the combustion valve 18 of the outdoor heat exchanger 3 which is a refrigerant heater to perform the pump down operation of the compressor 1 for a certain period of time, so that the refrigerant decreases during the heating cycle. Can be prevented, abnormal overheating of the refrigerant in the outdoor heat exchanger 3 as a refrigerant heater can be prevented, refrigerant thermal decomposition can be prevented, and system reliability is improved.

Effects of the Invention As described above, according to the cooling and heating apparatus of the present invention, during the heating operation, the accumulation of the refrigerant from the heating cycle to the stopped compressor separated from the heating cycle is suppressed by the indoor temperature detector after the heating operation is started. By using the timing when the temperature of the room temperature reaches the set value and the combustion of the refrigerant heater is stopped, there is a control device that keeps the compressor pump down for a certain period of time when the pressure in the heating cycle drops. There is an effect that the thermal decomposition of the refrigerant due to abnormal overheating of the refrigerant in the outdoor heat exchanger, which is the refrigerant heater, due to the decrease of the refrigerant inside can be prevented and the system reliability is improved.

Further, since the pump down is executed using the timing when the indoor set temperature is reached, comfortable heating can be realized without giving the user room temperature fluctuation.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of an air conditioner according to an embodiment of the present invention, and FIG. 2 is a circuit configuration diagram of a conventional air conditioner. 1 ... compressor, 2 ... first check valve, 3 ... outdoor heat exchanger, 4 ... pressure reducing device, 5 ... first solenoid valve, 6 ... indoor heat exchanger, 7 ... second Solenoid valve, 9 …… Second check valve, 10 ……
Liquid receiver, 11 …… Third check valve, 12 …… Open / close valve, 13 …… Third
Solenoid valve, 16 …… Indoor temperature detector, 17 …… Control device.

Claims (1)

[Claims] 1. A compressor, a first check valve, a refrigerant heater for heating,
A refrigeration cycle including an outdoor heat exchanger that serves as a condenser during cooling, a pressure reducing device, a first solenoid valve, an indoor heat exchanger, a second solenoid valve, and an accumulator, and the refrigeration device and the first solenoid valve connected in parallel. A second check valve, a liquid receiver, a third check valve, and a pressure equalizing pipe having an opening / closing valve between the liquid receiver and the first check valve and the outdoor heat exchanger; A heating pipe having a third solenoid valve between the check valve and the on-off valve and between the second solenoid valve and the indoor heat exchanger, and a refrigerant when the indoor temperature detector reaches a set temperature after the start of heating operation. A cooling and heating device comprising: a controller that stops combustion of the outdoor heat exchanger of the heater and performs the compressor operation for a certain period of time with the second electromagnetic valve closed.