JP2615502B2 - Air conditioning - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for performing cooling and heating by connecting an indoor / outdoor unit to a refrigerant pipe, and in particular, heats a refrigerant by a burner or the like and heat-transports to an indoor unit for heating. The present invention relates to a cooling and heating device.

2. Description of the Related Art Conventionally, as shown in FIG. 3, this type of cooling and heating apparatus heats a refrigerant heater 2 by a burner 1, and the heated and vaporized refrigerant passes through a pressure equalizing tube 3 and is transferred from a gas-liquid separator 4 to a fourth The air is pressure-fed to the indoor heat exchanger 7 via the check valve 5 and the four-way valve 6, radiated and condensed into a liquid refrigerant, and flows into the receiver 9 via the second check valve 8. When the liquid refrigerant accumulates in the liquid receiver 9, the on-off valve 10 is opened, and the liquid refrigerant by its own weight is discharged from the liquid receiver 9 disposed above the refrigerant heater 2 to the first check valve 11, gas-liquid The refrigerant flows into the refrigerant heater 2 via the separator 4. At this time, the refrigerant heater 2 and the liquid receiver 9
Is equalized by the equalizing pipe 3, and the liquid refrigerant from the indoor heat exchanger 7 does not flow into the receiver 9 by the second check valve 8. Next, when the liquid refrigerant in the liquid receiver 9 runs out, the on-off valve 10 is closed, and the condensed liquid refrigerant pools in the liquid receiver 9 again. At this time, the liquid refrigerant flowing into the liquid receiver 9 by the first check valve 11 does not flow to the gas-liquid separator 4 and the refrigerant heater 2. Further, the first to third solenoid valves 12, 13, and 14 are closed.

As described above, by repeatedly opening and closing the on-off valve 10, the liquid refrigerant is intermittently supplied from the liquid receiver 9 to the refrigerant heater 2 via the gas-liquid separator 4. The cycle in which the supplied refrigerant is pressure-fed to the indoor heat exchanger 7 is repeated during the heating operation.

Also, most refrigerants (mainly liquid refrigerants) at the start of heating
Is in the indoor heat exchanger 7 (for example, the indoor heat exchanger 7
Is lower than the other components. Alternatively, the temperature of the indoor heat exchanger 7 during heating is lower than the temperatures of the other components. )
If there is no refrigerant in the receiver 9, the gas-liquid separator 4, and the refrigerant heater 2,
When the gas refrigerant exists between the indoor heat exchanger 7 and the second check valve 8, it takes time until the liquid refrigerant returns to the receiver 9, and the refrigerant may not be supplied to the refrigerant heater 2. As a result, the temperature of the refrigerant in the refrigerant heater 2 rises abnormally, and the thermal stability of the refrigerant and, consequently, the reliability of the system is reduced or the heating start is delayed.

In order to prevent such a problem, the applicant has proposed that the first and second solenoid valves be used before heating the refrigerant by the burner 1 at the time of starting heating.
By opening the compressors 12 and 13 and driving the compressor 15 for a certain period of time, the refrigerant in the receiver 9 is sucked into the compressor 15 via the outdoor heat exchanger 16 so that the liquid accumulated in the indoor heat exchanger 7 A cycle in which the refrigerant is sucked into the receiver 9 and the gas refrigerant between the indoor heat exchanger 7 and the second check valve 8 is removed, the liquid refrigerant is secured in the receiver 9 in a short time, and heating is started. Was proposed by Japanese Patent Application No. 63-133282.

Problems to be Solved by the Invention However, in the above-described configuration, the liquid refrigerant does not accumulate in the indoor heat exchanger 7 during frequent heating on / off (for example, on / off by indoor room thermo), or the indoor heat exchanger 7 Since the compressor 15 is driven at the time of starting heating even when no gas refrigerant is accumulated between the second check valves 8, there are problems such as an increase in operating cost and a decrease in the reliability of the compressor 15.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and has as its object the inexpensive operation cost of the apparatus and the improvement of the reliability of the compressor.

Means for Solving the Problems In order to solve the above problems, the cooling and heating device of the present invention, after heating is stopped, the refrigerant in the refrigerant heater flows to the indoor heat exchanger by the residual heat of the refrigerant heater, and the refrigerant in the refrigerant heater Focusing on the fact that when the amount of refrigerant decreases, the temperature of the refrigerant heater rises, and a temperature detector is provided in the refrigerant heater.After heating is stopped, the temperature difference between the initial temperature of the refrigerant heater detected by the temperature detector and the current temperature is detected. If the temperature difference is reduced (-) when heating is restarted, the compressor is driven for a certain time before the refrigerant is heated by the burner, and the refrigerant in the liquid receiver and the refrigerant heater is opened and closed. It has a configuration having a control mechanism for pushing out to an indoor heat exchanger via a valve, a solenoid valve, an outdoor heat exchanger, a four-way valve, and an accumulator.

Operation The present invention detects the temperature of the refrigerant heater from the previous heating stop with the temperature detector, calculates the temperature difference between the detected initial temperature and the current temperature of the refrigerant heater, and restarts the heating when the heating is restarted. If the temperature difference decreases (-), open the on-off valve and solenoid valve before heating the refrigerant with the burner, drive the compressor for a certain period of time, and secure new liquid refrigerant in the receiver and heater. And then heat the refrigerant with a burner.
Heat the refrigerant with a burner. As a result, it is possible to guarantee a reliable heating start at the time of heating ON / OFF, reduce the drive time of the compressor, and reduce the number of times of ON / OFF, thereby reducing the operating cost and ensuring the reliability of the compressor.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows the overall configuration of a cooling and heating apparatus according to the present invention, in which 17 is an outdoor unit, 18 is an indoor unit, and 19 and 20 are refrigerant pipes connecting the outdoor unit 17 and the indoor unit 18. 21 is a heat transfer heating block used for heating,
A refrigerant heater having an open / close valve 22, a liquid receiver 23, a first check valve 24, a gas-liquid separator 25, and a burner 26 at the lowermost part in order from the top.
There are 27. Also, a suction pipe 28 connecting the refrigerant heater 27 and the lowermost part of the gas-liquid separator 25, an outlet pipe 29 connecting the refrigerant heater 27 to the upper part of the gas-liquid separator 25, and an inlet / closing valve 22 inlet from the upper part of the gas-liquid separator 25. Equalizing tube 30 provided in the tank, Refrigerant drain tube 3 branched from equalizing tube 30
1. A branch pipe 32 branched from the refrigerant drain pipe 31 to communicate with the refrigerant heater 30, a return pipe 33 provided to allow the refrigerant to flow from the upper part of the liquid receiver 23, and a second pipe provided in the return pipe 33. A cooling pressure reducing mechanism 35 provided in parallel with the check valve 34 and the second check valve 34 is configured as a main member. 36 is a compressor, 37 is a third check valve provided between the compressor 36 and the four-way valve 38, and 39 is a heating pipe extending from above the gas-liquid separator 25 to between the four-way valve 38 and the third check valve 37. A fourth check valve 40 is provided in the middle of the road. Reference numeral 41 denotes an electromagnetic valve provided between the refrigerant vent pipe 31 and the outdoor heat exchanger 42, and the outdoor heat exchanger 42 and the four-way valve 38 are in communication.

Also, the second check valve 34 and the indoor heat exchanger in the indoor unit 18
43 is communicated with the refrigerant pipe 20. On the other hand, the four-way valve 38 and the indoor heat exchanger 43 in the indoor unit 18 are connected by the refrigerant pipe 19. 44 is an accumulator provided between the four-way valve 38 and the suction side of the compressor 36; 45 is a temperature detector provided in the refrigerant heater 27; 46 is a temperature detector 45;
A control mechanism that controls the on-off valve 22, the solenoid valve 41, the burner 26, and the compressor 36 by turning on / off 47 (heating on / off).
The control flow is as shown in FIG.

In the above configuration, during the cooling operation, the four-way valve 38 is turned on (dotted line in the figure), the solenoid valve 41 and the on-off valve 22 are open, and the high-temperature and high-pressure gas refrigerant discharged from the compressor 36
The air enters the outdoor heat exchanger 42 through the check valve 37 and the four-way valve 38.

After being radiated and condensed in the outdoor heat exchanger 42, the refrigerant passes through the solenoid valve 41 and is diverted to the refrigerant vent pipe 31 and the vent pipe 32. The refrigerant diverted to the drain pipe 32 passes through the refrigerant heater 27, the outlet pipe 29, the suction pipe 28, enters the gas-liquid separator 25, passes through the pressure equalizing pipe 30, and passes through the refrigerant drain pipe 31.
To join. After merging, on-off valve 22, liquid receiver 23, return pipe 33
And enters the cooling decompression mechanism 35. The refrigerant decompressed and expanded by the cooling decompression mechanism 35 enters the indoor heat exchanger 43 from the refrigerant pipe 20, evaporates and gasifies, and returns to the compressor 36 via the refrigerant pipe 19, the four-way valve 38, and the accumulator 44. Cooling is performed by this cycle.

On the other hand, during the heating operation, the four-way valve 38 is in the off state (solid line in the figure), the solenoid valve 41 is in the closed state, and the on-off valve 22 repeats the opening / closing operation to start burning the burner 26.

Here, the liquid refrigerant accumulated in the liquid receiver 23 passes through the first check valve 24 and the gas-liquid separator 25, and is supplied from the suction pipe 28 to the refrigerant heater 27. The refrigerant heated by the burner 26 in the refrigerant heater 27 is
Only the gas refrigerant from the outlet pipe 29 through the gas-liquid separator 25 is heated
After passing through 39, the refrigerant is pressure-fed from the refrigerant pipe 19 to the indoor heat exchanger 43 via the fourth check valve 40 and the four-way valve 38 to be condensed and liquefied. At this time, if the on-off valve 22 is in the closed state, the condensed and liquefied refrigerant flows into the receiver 23 through the refrigerant line 20, the return pipe 33, and the second check valve 34, and the receiver 23 When the liquid refrigerant accumulation is completed, the on-off valve
22 is opened, and the refrigerant in the receiver 23
Due to the pressure of 30, the gas flows from the first check valve 24 to the gas-liquid separator 25, and from the gas-liquid separator 25 to the refrigerant heater 27 by the suction pipe 28. When the on-off valve 22 is closed, the condensed liquid refrigerant does not flow into the receiver 23.

The above operation is repeated, the liquid refrigerant is intermittently supplied to the refrigerant heater 27, and the gas refrigerant is pressure-fed to the indoor heat exchanger 43.

On the other hand, during the heating operation and at the time of turning on / off the indoor room thermo 47, as shown in the control flow of FIG. 2, the control mechanism 46 determines whether or not the temperature of the indoor room thermo 47 has reached the set off temperature. 26 combustion is off, detects the initial temperature Ta ₁ of the refrigerant heater 27 by the temperature detector 45. Thereafter, the current temperature Ta ₂ of the refrigerant heater 27 is detected again, and T
Calculate the temperature difference ΔTa between a ₁ and Ta ₂ . After the ΔTa calculation, the current temperature Ta ₂ is replaced with the initial temperature Ta _1, and it is determined whether the temperature of the room thermo 47 has reached the ON set temperature. Detection of reaching though unless current temperature Ta _2, replaced ΔTa calculated from Ta ₂ to Ta _1, enters the ON determination room thermo 47. Conversely, if the temperature of the room thermo 47 has reached the ON set temperature, ΔTa
Is determined to increase or decrease. If ΔTa is 0 to increase (+), the on-off valve 22 performs an on-off operation to ignite the burner 26,
The refrigerant is heated by the refrigerant heater 27 and the normal heating operation is started.

Conversely, if ΔTa is reduced (-), the amount of refrigerant in the refrigerant heater 27 is reduced, so that the on-off valve 22 and the solenoid valve 41 are opened first, the compressor 36 is driven, and the liquid receiver 23, the refrigerant The refrigerant in the heater 27 is sucked into the compressor 36 via the on-off valve 22, the solenoid valve 41, the outdoor heat exchanger 42, the four-way valve 38, and the accumulator 44. The refrigerant drawn into the compressor 36 passes through the third check valve 37 and the four-way valve 38 and is discharged to the indoor heat exchanger 43. When the refrigerant in the receiver 23 is drained, the liquid refrigerant accumulated in the indoor heat exchanger 43 is discharged to the refrigerant pipe 2
0, through the return pipe 33, the second check valve 34, flows into the receiver 23,
It also enters the refrigerant heater 27. Further, if there is a gas refrigerant in the refrigerant pipe 20 and the return pipe 33, the gas refrigerant is simultaneously drawn into the compressor 36 from the liquid receiver 23 and the refrigerant heater 27. The timer is counted at the same time as the compressor 36 is driven, and when the timer exceeds a certain time,
First, the on-off valve 22 and the solenoid valve 41 are closed, and the refrigerant accumulated in the outdoor heat exchanger 42 is pumped. After that, when the timer reaches the set time, the compressor 36 stops. After the compressor 36 stops, the on-off valve 22 performs an on-off operation, ignites the burner 26, heats the refrigerant with the refrigerant heater 27, and enters a normal heating operation. Thus, it is calculated whether the temperature difference ΔTa of the refrigerant heater 27 has increased or decreased since the heating was stopped,
The presence / absence of the refrigerant in the refrigerant heater 27 is determined, and the presence / absence of the operation of the on-off valve 22, the solenoid valve 41, and the compressor 36 at the time of heating restart is determined. This ensures a reliable heating start during frequent heating on / off such as turning on / off the indoor room thermo 46, and reduces the driving time and the number of on / off times of the compressor 36 to reduce the operating cost and ensure the reliability of the compressor 36. it can.

Effects of the Invention As described above, according to the cooling and heating device of the present invention, the temperature of the refrigerant heater is detected by the temperature detector after the heating is stopped, and the temperature difference between the detected initial temperature and the current temperature of the refrigerant heater is calculated, If the temperature difference is 0 or increased (+), at the time of restarting heating, the burner is ignited without operating the compressor, the refrigerant is heated, and the heating operation is started. Conversely, if the temperature difference is reduced (-), the compressor is driven for a certain time before the refrigerant is heated by the burner, and the refrigerant in the liquid receiver and the refrigerant heater is discharged by the on-off valve, the solenoid valve, and the outdoor. After being pushed out to the indoor heat exchanger via the heat exchanger, the four-way valve and the accumulator, the burner ignition heating restart is started. By providing the above control mechanism, for frequent heating on / off, a reliable heating start guarantee and a compressor driving time,
The number of on / off times can be minimized, and the operating cost can be reduced and the reliability of the compressor can be ensured.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a refrigerant circuit configuration diagram of a cooling and heating device according to an embodiment of the present invention, FIG. 2 is a control flowchart of the control mechanism, and FIG. 3 is a refrigerant circuit configuration diagram of a conventional cooling and heating device. It is. 21 heat transfer heating block, 22 on-off valve, 23 liquid receiver, 24 first check valve, 25 gas-liquid separator, 26 burner, 27 refrigerant heater, 34 second check valve, 35 pressure reducing mechanism, 36 compressor, 37 third check valve, 38 four-way valve, 41 solenoid valve, 42 outdoor heat exchanger, 43 …… indoor heat exchanger, 44 …… accumulator, 45 …… temperature detector,
46 ... Control mechanism.

Claims (1)

(57) [Claims] An on-off valve, a liquid receiver, and a first valve provided in this order from the top.
A refrigerant heater equipped with a check valve, a gas-liquid separator, and a burner;
A suction pipe connecting the refrigerant heater to the lower part of the gas-liquid separator, an outlet pipe connecting the refrigerant heater to the upper part of the gas-liquid separator, an equalizing pipe connecting the upper part of the gas-liquid separator to the on-off valve inlet, and a pressure equalizing pipe A refrigerant drain pipe branched from the pipe, a drain pipe branched from the refrigerant drain pipe and connected to the refrigerant heater, a return pipe connected to the upper part of the liquid receiver, a second check valve provided in the return pipe, (2) a heat transfer and heating block including a pressure reducing mechanism provided in parallel with the check valve, a refrigerant vent pipe connected to the on-off valve inlet, a solenoid valve, an outdoor heat exchanger, the four-way valve, an accumulator, Connecting the compressor, connecting the compressor, the third check valve, the four-way valve, the indoor heat exchanger, and the return pipe, and connecting the gas-liquid separator to the fourth check valve. A heating pipe connected between the four-way valve and the third check valve via a valve is provided, and the refrigerant heater is provided with a temperature. An alarm is provided, and after the heating is stopped, the temperature difference between the initial temperature and the current temperature of the refrigerant heater detected by the temperature detector is calculated, and when the heating is restarted, if the temperature difference is reduced (-), the on-off valve is opened. , Open the solenoid valve, and keep the compressor constant so that the refrigerant in the receiver and the refrigerant heater is pushed out to the indoor heat exchanger through the on-off valve, solenoid valve, outdoor heat exchanger, four-way valve, and accumulator An air conditioner with a control mechanism that operates for hours.