JP2658457B2 - Heating and cooling machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a warming / cooling machine which operates with an electric compressor during cooling and a combustion heat from a refrigerant heater during heating using a non-powered heat transfer system.

2. Description of the Related Art A conventional non-powered heat transfer type heating device has a gas-liquid separator 3 disposed at an intermediate position of a liquid receiver 2 located above a refrigerant heater 1 as shown in FIG. 2 and the gas-liquid separator 3, there is an on-off valve 4 for making the both uniform, and a check valve 5 is provided between the liquid receiver 2 and the gas-liquid separator 3, and the refrigerant evaporated by the refrigerant heater 1 is It condenses in the indoor heat exchanger 6 and flows into the liquid receiver 2. When the liquid refrigerant accumulates in the liquid receiver 2, the on-off valve 4 is opened to equalize the pressure of the liquid receiver 2 and the gas-liquid separator 3, and the liquid refrigerant in the liquid receiver 2 flows into the gas-liquid separator 3. When the inflow has been completed, the on-off valve 4 is closed and the check valve 5 is also closed, so that the liquid refrigerant condensed from the indoor heat exchanger 6 flows into the receiver 2 again. Heating operation is performed by repeating such an operation to carry out heat transfer. (For example, Japanese Utility Model Laid-Open No. 43679/1986) A refrigerant circuit as shown in FIG. 3 is conceivable for performing the cooling operation with the compressor during heating and using the non-powered heat transfer method during cooling. The same members as those in FIG. 2 are given the same numbers. Prior to the heating operation, the first solenoid valve 7 and the second solenoid valve 8 are closed to perform a pump-down operation in which the refrigerant in the outdoor heat exchanger 9 is pumped by the compressor 10, and the third check valve 11 to the heating operation circuit. Discharge.
After the pump down, the compressor 10 is stopped and the refrigerant evaporated in the burner-equipped refrigerant heater 1 is separated into gas and liquid by the gas-liquid separator 3 and only the gas refrigerant passes through the fourth check valve 13 and the four-way valve 12. It condenses in the indoor heat exchanger 6 and flows into the liquid receiver 2 through the first check valve 14. At this time, since the on-off valve 4 and the second check valve 5 are closed, when the liquid refrigerant flows into the receiver 2, the gas refrigerant inside the receiver 2 is condensed and the pressure in the receiver 2 decreases. The liquid refrigerant is drawn into the receiver 2 from the indoor heat exchanger 6, and when the liquid refrigerant accumulates in the receiver 2, the opening / closing valve 4 is opened and the operation described in the non-powered heat transfer type heating device is performed. The first solenoid valve during heating operation,
The second solenoid valve 8 is in a closed state. During the cooling operation, the refrigerant that has become high temperature and high pressure in the compressor 10 is supplied to the third check valve 11, the four-way valve 12, the outdoor heat exchanger 9, the first solenoid valve, the refrigerant heater 1 with a burner, and the second.
The refrigerant evaporates in the indoor heat exchanger 6 through the solenoid valve 8 and the pressure reducing mechanism 15 and returns to the compressor 10.

However, in the above-described configuration, the heating operation is performed by the refrigerant conveying means including the liquid receiver 2, the on-off valve 4, the first check valve 14, the second check valve 5, and the gas-liquid separator 3. When the heating operation is performed, the refrigerant needs a large degree of supercooling at the outlet of the indoor heat exchanger 6 as is clear from the above operation description, and after the heating operation is stopped, a considerably large amount of refrigerant is distributed to the indoor heat exchanger 6. Therefore, when performing the cooling operation from this state, a large amount of refrigerant in the indoor heat exchanger 6 is absorbed by the compressor 10 through the four-way valve 12,
There is a problem that liquid compression occurs in the compressor 10 and reliability of the compressor 10 is reduced. In addition, when a large amount of refrigerant returns to the compressor 10 at one time, the refrigerating machine oil in the compressor 10 is also discharged from the compressor.For example, in a trial operation after installation work, the cooling operation is performed for a short time after the heating operation, and then the heating operation is performed again. When the operation is performed, the refrigerating machine oil discharged from the compressor does not sufficiently return to the compressor, the refrigerant in the outdoor heat exchanger 9 is pumped to the heating circuit side, and the burner is ignited after the compressor is stopped. The refrigerating machine oil remaining on the side gradually condenses to the refrigerant heater 1 with the burner during the heating operation, the heat exchange efficiency between the combustion heat of the burner and the refrigerant decreases, and the surface temperature of the refrigerant heater 1 with the burner abnormally increases. There was also a problem that stable heating operation could not be performed.

The present invention solves the above-mentioned conventional problems, and in the case of performing the heating operation last time and then performing the cooling operation, the refrigerant distributed to the indoor heat exchanger in a large amount to the upstream side of the pressure reducing mechanism in the cooling circuit. Prevents a large amount of refrigerant from being moved and distributed to the indoor heat exchanger from returning directly to the compressor via the four-way valve to compress the liquid, and stable heating operation even if the operation mode of heating and cooling is frequently switched. It is an object of the present invention to provide a highly reliable heating / cooling machine capable of performing the following.

Means for Solving the Problems In order to solve the above problems, a heating / cooling machine of the present invention includes a compressor, a four-way valve, an outdoor heat exchanger, a refrigerant heater with a burner, a pressure reducing mechanism, an indoor heat exchanger, and the four-way valve. , The compressor is sequentially connected, and above the refrigerant heater with a burner, a refrigerant conveying means having an outlet side connected between the four-way valve and the compressor and an inlet side connected to the indoor heat exchanger is connected. The refrigerant conveying means separates the refrigerant supplied from the burner-equipped refrigerant heater into gas and liquid, sends out the gas-phase refrigerant between the compressor and the four-way valve, and the liquid refrigerant evaporates from the burner-equipped refrigerant heater. And the liquid refrigerant sucked from the indoor heat exchanger is returned to the burner-equipped refrigerant heater by its own weight by opening an on-off valve. During the heating operation, the burner-equipped refrigerant heater, heat transfer means, four-way valve , The indoor heat exchanger, and the compressor, four-way valve, and room during cooling operation. An external heat exchanger, a refrigerant heater with a burner, a decompression mechanism, a refrigerant circuit in which the refrigerant flows in the order of the indoor heat exchanger, and when switching from the heating operation to the cooling operation, the four-way valve is operated for a certain time after the cooling operation compressor is started. It is provided with a control device for holding on the heating side and then switching to the cooling side.

Operation The present invention is configured such that when the heating operation is performed last time and then the cooling operation is performed by the above-described configuration, the refrigerant distributed in a large amount to the indoor heat exchanger is moved to the upstream side of the pressure reducing mechanism in the cooling circuit, and the indoor heat exchanger is operated. In addition to preventing a large amount of refrigerant distributed to the compressor from being directly returned to the compressor via the four-way valve, for example, even in a case where the heating operation is performed for a short time after the heating operation in the test operation after the installation work, and then the heating operation is performed again. During cooling operation, a large amount of refrigerant in the indoor heat exchanger does not return directly to the compressor via the four-way valve.As a result, the amount of refrigerating machine oil in the compressor discharged from the compressor to the refrigerant circuit also decreases, so a short time after heating operation. Even after the cooling operation and the heating operation, the refrigerating machine oil gradually condenses to the refrigerant heater with the burner during the heating operation, the heat exchange efficiency between the burner combustion heat and the refrigerant decreases, and the surface temperature of the refrigerant heater with the burner is abnormal. Can be prevented from rising Therefore, the reliability of the equipment can be improved and the stable heating operation can be performed.

Embodiment An embodiment of the present invention will be described below with reference to FIG. The same members as those in FIG. 3 are denoted by the same reference numerals.
In FIG. 1, reference numeral 1 denotes a refrigerant heater with a burner disposed below the gas-liquid separator 3 and connected to the gas-liquid separator 3 in a loop by a refrigerant heater inlet pipe 21 and a refrigerant heater outlet pipe 22. Container, 2
Is a liquid receiver disposed above the gas-liquid separator 3 via the second check valve 5 and connected to the pressure equalizing pipe 23 above the liquid receiver 2 from above the gas-liquid separator 3. On-off valve 4 and heating fluid pipe
A connection pipe 20 of the first check valve 14 connected to 24 is provided. From above the gas-liquid separator 3, a pipe is connected between a third check valve 11 and a four-way valve 12 disposed on a discharge pipe of the compressor 10 via a fourth check valve 13. 9 is an outdoor heat exchanger having an outdoor fan 25, 7 is a first solenoid valve, 8 is a second solenoid valve, and 15 is a decompression mechanism. Reference numeral 31 denotes a control device, which includes an operation mode storage unit 27 for storing the previous heating operation or the cooling operation, a timer operation switching unit 28 for switching the operation of the timer 29, and a four-way valve drive control unit 30. Reference numeral 6 denotes an indoor heat exchanger having an indoor fan 26. The outdoor unit 16 and the indoor unit 17 are connected to refrigerant connection pipes 18 and 19 in an annular manner.

In the above configuration, during the heating operation, the refrigerant in the outdoor heat exchanger 9 which is not in the heating circuit is pumped to the indoor heat exchanger 17 by operating the compressor 10 with the first solenoid valve 7 closed. After the pumping operation is completed, the compressor 10 is stopped, and the refrigerant heated by the refrigerant heater 1 with the burner flows into the gas-liquid separator 3 through the refrigerant heater outlet pipe 22 in a two-phase state, and the liquid refrigerant is heated again by the refrigerant. It flows into the burner-equipped refrigerant heater 1 through the vessel inlet pipe 21. On the other hand, the gas refrigerant of the two-phase refrigerant flowing from the refrigerant heater 1 with the burner into the gas-liquid separator 3 is sent to the indoor heat exchanger 6 through the fourth check valve 13 and the four-way valve 12 under pressure, and the indoor fan 26 is operated. To condense and liquefy. At this time, when the on-off valve 4 is closed, the second check valve 5 is closed and the liquid refrigerant having a large degree of supercooling is sent to the receiver 2 from the indoor heat exchanger 6 through the first check valve 14. Then, the gas refrigerant in the liquid receiver 2 is condensed and liquefied, and the pressure in the liquid receiver 2 rapidly decreases, and the supercooled liquid refrigerant in the indoor heat exchanger 6 is drawn into the liquid receiver 2 and filled. When the on-off valve 4 is opened in this state, the liquid receiver 2 and the gas-liquid separator 3 are in a pressure equalized state, and the liquid refrigerant in the liquid receiver 2 passes through the second check valve 5 and enters the gas-liquid separator 3. Inflow. At this time, the first check valve 14 is in the closed state. Next, when the on-off valve 4 is closed, the second check valve 5 is closed and the supercooled liquid refrigerant flows into the receiver 2 again from the indoor heat exchanger 6 to fill the receiver 2 with the liquid refrigerant and open the on-off valve. Is repeated. That is, the liquid receiver 2, the on-off valve 4, the first check valve 14, the second check valve 5, and the gas-liquid separator 3 constitute a refrigerant conveying means, and the space between the gas-liquid separator 3 and the refrigerant heater 1 is provided. The refrigerant circuit of the natural circulation circuit, the gas-liquid separator 3, the indoor heat exchanger 6, the first check valve 14, the receiver 2, and the second check valve 5 intermittently uses the supercooled liquid refrigerant of the indoor heat exchanger 6. It is to return to the gas-liquid separator 3 via the liquid receiver 2. During the cooling operation, the four-way valve 12 is switched so that the gas discharged from the compressor 10 flows to the outdoor heat exchanger 9, the first electromagnetic valve 7 and the second electromagnetic valve 8 are opened, and the four-way valve 12 passes through the pressure reducing mechanism 15 and the indoor heat exchanger 6. Return to the compressor 10.

Here, when switching from heating operation to cooling operation,
Timer switching operation unit based on signal from operation mode storage unit 27
Since 28 switches to the one where the timer 29 operates, the first solenoid valve 7
The second solenoid valve 8 is opened to start the cooling operation. After starting the compressor, the timer 29 keeps the four-way valve 12 on the heating side for a certain period of time, and then switches to the cooling side by the four-way valve drive control unit 30. A large amount of refrigerant distributed to the first check valve 14
Flows through the receiver 2 to the gas-liquid separator 3, moves to the upstream side of the pressure reducing mechanism 15 in the cooling circuit, and as a result, the refrigerant of the indoor heat exchanger 6 returns directly to the compressor 10 via the four-way valve 12. It is possible to prevent the liquid from being compressed, and also to prevent the refrigerating machine oil from being taken out of the compressor 10, thereby enabling a stable heating / cooling switching operation.

Effect of the Invention As described above, according to the heating and cooling device of the present invention, when switching from the heating operation to the cooling operation, a large amount of the refrigerant distributed to the indoor heat exchanger is moved to the upstream side of the pressure reducing mechanism of the cooling circuit. Accordingly, the reliability of the compressor and the refrigerant heater with a burner due to the return of the liquid to the compressor and the accompanying removal of the refrigerating machine oil from the compressor can be prevented, and a stable heating / cooling switching operation can be performed.

[Brief description of the drawings]

FIG. 1 is a circuit configuration diagram of a heating / cooling machine according to one embodiment of the present invention, FIG. 2 is a circuit configuration diagram of a conventional heating device, and FIG. 3 is a circuit configuration diagram of a conventional heating / cooling device. DESCRIPTION OF SYMBOLS 1 ... Refrigerant heater with a burner, 2 ... Liquid receiver, 3 ... Gas-liquid separator, 4 ... On-off valve, 5 ... Second check valve, 10 ... Compressor, 12 ... 4-way valve , 14 first check valve, 15 pressure reducing mechanism, 27 operation mode storage unit, 28 timer operation switching unit, 29 timer, 30 four-way valve drive control unit, 31 control apparatus.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shozo Kokawa Kawaji, Kazuma, Osaka 1006, Kazuma Matsushita Electric Industrial Co., Ltd. (72) Inventor Katsuhiko Yamamoto 1006, Kazuma, Kadoma, Kazuma, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Hirohisa Imai 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (1)

(57) [Claims] 1. A compressor, a four-way valve, an outdoor heat exchanger, a refrigerant heater with a burner, a decompression mechanism, an indoor heat exchanger, the four-way valve, the compressor are connected in sequence, and the refrigerant heater with a burner is connected. On the upper side, the outlet side is connected between the four-way valve and the compressor, and the refrigerant conveying means having the inlet side connected to the indoor heat exchanger is connected,
This refrigerant transport means separates the refrigerant supplied from the burner-equipped heater into gas and liquid, sends out the gas-phase refrigerant between the compressor and the four-way valve, and returns the liquid refrigerant to the burner-equipped refrigerant heater. And the liquid refrigerant sucked from the indoor heat exchanger is configured to return to the burner-equipped refrigerant heater by its own weight by opening the on-off valve, and during the heating operation, the burner-equipped refrigerant heater, the heat transfer means, the four-way valve, and the indoor In the order of the heat exchanger, during the cooling operation, a compressor, a four-way valve, an outdoor heat exchanger, a refrigerant heater with a burner, a decompression mechanism, and a refrigerant circuit in which the refrigerant flows in the order of the indoor heat exchanger are configured.From the heating operation to the cooling operation, A heating / cooling machine having a control device for holding the four-way valve on the heating side for a certain period of time after the start of the compressor for cooling operation and then switching to the cooling side.