JPH09303898A - Driving control method for air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a positive elimination of pressure difference left in a freezing cycle to be carried out and at the same time to reduce a load for a compressor by adjusting a pressure balance within a freezing cycle when an operation is started. SOLUTION: The air conditioner is provided with a freezing cycle comprising a refrigerant compressor, an indoor heat exchanger, an outdoor heat exchanger, a pressure reducing machine placed between the indoor heat exchanger and the outdoor heat exchanger and a four-way valve for changing-over a connection between the refrigerant compressor and the indoor heat exchanger or the outdoor heat exchanger. In this case, an air conditioner is operated so that when the air conditioner is energized (a time 12), after the four-way valve is set to a cooling operation side for a predetermined time (T1), the four-way valve is changed over to a heating operation at the time 13, the four-way valve is changed over to either a cooling operation or a heating operation in accordance with its subsequent operation mode at the time 14 elapsed by a predetermined time (T2) and concurrently the compressor is driven at this time.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a refrigerant compressor, an indoor heat exchanger, an outdoor heat exchanger, and a decompressor interposed between the indoor heat exchanger and the outdoor heat exchanger,
The present invention relates to an air conditioner including a refrigeration cycle formed by a four-way valve that switches a connection method between the refrigerant compressor, the indoor heat exchanger, and the outdoor heat exchanger, more specifically, a refrigeration cycle at startup. The present invention relates to a drive control method for an air conditioner that adjusts the pressure balance in the interior.

[0002]

2. Description of the Related Art In a conventional air conditioner, by switching the four-way valve, during cooling operation, the refrigerant compressed by the compressor is transferred to the four-way valve, the indoor heat exchanger, the pressure reducer, the outdoor heat exchanger, and the four-way valve. Circulates again to the compressor through the route of, and during heating operation, the refrigerant compressed by the compressor returns to the compressor via the route of the four-way valve, the outdoor heat exchanger, the pressure reducer, the indoor heat exchanger, and the four-way valve. Circulating.

[0003]

In the air conditioner having such a configuration, for example, about 3 minutes after the cooling operation is stopped,
Even if a drive signal is input to the compressor, the compressor will not restart. This is because when the compressor operates, if there is a pressure difference in the refrigeration cycle, the pressure difference may damage the compressor.

However, even if the restart of the compressor is restricted for about 3 minutes after the cooling operation is stopped, there is no guarantee that the pressure difference in the refrigeration cycle will be completely eliminated after 3 minutes. When the machine was restarted, there was a problem that the compressor might be locked due to the remaining pressure difference. Further, if such use is carried out for a long period of time, the load on the compressor becomes non-negligible, which has been a factor of shortening the life of the compressor.

The present invention was devised to solve the above problems, and its purpose is to reliably eliminate the pressure difference remaining in the refrigeration cycle by adjusting the pressure balance in the refrigeration cycle at the time of startup. While being able to
An object of the present invention is to provide a drive control method for an air conditioner that reduces the load on the compressor.

[0006]

In order to solve the above problems, a drive control method for an air conditioner according to claim 1 of the present invention comprises a refrigerant compressor, an indoor heat exchanger, an outdoor heat exchanger, Formed by a pressure reducer inserted between the indoor heat exchanger and the outdoor heat exchanger, and a four-way valve that switches the connection method between the refrigerant compressor and the indoor heat exchanger and the outdoor heat exchanger In an air conditioner equipped with a refrigeration cycle, when the air conditioner is started, the four-way valve is switched between a cooling operation side and a heating operation side for a predetermined period of time, and then the four-way valve is cooled according to a subsequent operation mode. The compressor is driven while switching to the operation side or the heating operation side.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram of an air conditioner to which the drive control method of the present invention is applied. In the figure, the discharge port 11 and the suction port 12 of the compressor 1 have an indoor side heat exchanger 3 having an indoor side fan 31 via a four-way valve 2.
One of the connection ports is connected to one connection port of the outdoor heat exchanger 5 having the outdoor fan 51, and the other connection port of the indoor heat exchanger 3 and the other connection of the outdoor heat exchanger 5 are connected. The mouth and the mouth are connected via the pressure reducer 4.

Then, during the heating operation, the discharge port 11 of the compressor 1 and the indoor heat exchanger 3 are switched by switching the four-way valve 2.
One of the connection ports is connected, and the suction port 12 of the compressor 1 and one connection port of the outdoor heat exchanger 5 are connected. Therefore, the high-temperature refrigerant compressed by the compressor 1 is The room is heated by flowing like the arrow shown by the broken line.

That is, the high-temperature refrigerant compressed by the compressor 1 is supplied to the indoor heat exchanger 3 through the four-way valve 2, where the indoor fan 31 forcibly exchanges heat to heat the room. The refrigerant condensed after the heat exchange by the indoor heat exchanger 3 is decompressed by the decompressor 4 and supplied to the outdoor heat exchanger 5, where the outdoor fan 51 forcibly heat-exchanges the outdoor heat. The surface temperature of the exchange 5 is lowered. The refrigerant that has undergone heat exchange by the outdoor heat exchanger 5 and is vaporized is circulated to the compressor 1 again through the four-way valve 2.

On the other hand, during cooling operation, by switching the four-way valve 2, the discharge port 11 of the compressor 1 and one connection port of the outdoor heat exchanger 5 are connected, and the suction port 12 of the compressor 1 and the indoor heat source. Since one of the connection ports of the exchange 3 is connected, the high temperature refrigerant compressed by the compressor 1 flows in the direction indicated by the solid line arrow in the figure to cool the room.

FIG. 2 is a drive circuit diagram for realizing the drive control method of the present invention. That is, a microcomputer 8 for controlling the operation of the entire air conditioner with respect to the commercial power supply 7, an opening / closing switch 1a of the compressor 1, an indoor fan 3
The opening / closing switch 31a of No. 1, the opening / closing switch 51a of the outdoor fan 51, and the changeover switch 2a of the four-way valve 2 are connected in parallel via the power switch 9. The microcomputer 8 has various operation modes (heating operation mode,
The open / close control and the change control of the respective open / close switches 1a, 31a, 51a and the changeover switch 2a are performed according to a program for executing a cooling operation mode, a dehumidifying operation mode, a trial operation mode, an automatic operation mode, and the like.

The changeover switch 2a of the four-way valve 2 is controlled by a solenoid (not shown).
The switch is always switched to the cooling operation side when the solenoid is off. That is, the discharge port 11 of the compressor 1 is connected to one connection port of the outdoor heat exchanger 5, and the suction port 12 of the compressor 1 is connected to one connection port of the indoor heat exchanger 3. Has become.

Drive control at the time of starting the operation of the air conditioner having the above configuration will be described with reference to the timing chart shown in FIG. As described above, the changeover switch 2a of the four-way valve 2 before turning on the power switch 9 is switched to the cooling operation side.

In this state, when the power switch 9 is turned on at time t1 and, for example, heating operation is started at time t2 (a heating operation switch (not shown) is turned on), the microcomputer 8 controls the changeover switch 2a of the four-way valve 2. Then, the discharge port 11 of the compressor 1 is connected to one of the connection ports of the outdoor heat exchanger 5, and the suction port 1 of the compressor 1 is connected.
2 is connected to one of the connection ports of the indoor heat exchanger 3. In other words, in this case, keep the solenoid off,
The state connected to the cooling operation side is maintained for a predetermined time T1 (for example, 5
s) Continue.

When the predetermined time T1 has elapsed,
At time t3, the microcomputer 8 causes the four-way valve 2
Of the discharge port 11 of the compressor 1 by controlling the changeover switch 2a of
Is connected to one of the connection ports of the indoor heat exchanger 3, and the suction port 12 of the compressor 1 is connected to one connection port of the outdoor heat exchanger 5. That is, at this time, the solenoid is turned on and the state of being connected to the heating operation side is continued for a predetermined time T2 (for example, about 5 seconds).

Then, at time t4 when this predetermined time (T1 + T2) has elapsed, the microcomputer 8
The opening / closing switch 1a of the compressor 1 is turned on, the pressurization of the refrigerant is started, and the heating operation is substantially started. Further, the microcomputer 8 controls the changeover switch 2a of the four-way valve 2 in accordance with the set heating operation mode, keeps the solenoid on and keeps the heating operation side connected.

As described above, at the start of the heating operation, the changeover switch 2a of the four-way valve 2 is switched to the cooling operation side for the predetermined time T1, and is switched to the heating operation side for the next predetermined time T2. At time t4 when the time (T1 + T2) has elapsed, the pressure difference in the refrigeration cycle is eliminated. Therefore, even if the open / close switch 1a of the compressor 1 is turned on at the time t4, no load is applied to the compressor 1 due to the pressure difference in the refrigeration cycle.

Further, since the drive control method of the present invention performs these series of controls when the air conditioner is started,
Actually, the pressure difference in the refrigeration cycle has been substantially eliminated, and therefore, the sound generated by the influence of the flow of the refrigerant when switching the four-way valve 2 is considerably small, and in some cases, the sound is completely silenced. . In the above embodiment, the drive control method of the present invention is explained during the heating operation, but the operation at startup is the same as that during the heating operation described above even in other operation modes. is there. However, during the cooling operation, the changeover switch 2a of the four-way valve 2 is at time t4 as shown by the broken line in FIG.
The solenoid is turned off to switch to the connection state on the cooling operation side.

In the above embodiment, the changeover switch 2a of the four-way valve 2 before turning on the power switch 9 is always switched to the cooling operation side in the initial state. When you finish driving,
When the operation is terminated in the connected state, the changeover switch 2a of the four-way valve 2 remains connected to the heating operation side (the solenoid is turned on in the above embodiment). In this case, as shown by the broken line in FIG.
In 2, the changeover switch 2a of the four-way valve 2 is changed over to the cooling operation side. The subsequent control is exactly the same as in the above-described embodiment.

Further, in the above-described embodiment, the switching state of the four-way valve 2 after the time t2 is changed to the heating operation side after the elapse of a predetermined time (T1) on the cooling operation side so that the predetermined time (T2) elapses. However, conversely, it may be configured such that after a predetermined time (T1) elapses on the heating operation side, the air conditioner is switched to the cooling operation side and a predetermined time (T2) elapses. In any case, when starting the air conditioner, the four-way valve 2
After switching between the cooling operation side and the heating operation side for a predetermined time, the four-way valve 2 is switched to the cooling operation side or the heating operation side according to the subsequent operation mode, and the compressor 1 is driven at this point. I have.

[0021]

The drive control method for the air conditioner of the present invention comprises:
Refrigerant compressor, indoor heat exchanger, outdoor heat exchanger,
A decompressor inserted between the indoor heat exchanger and the outdoor heat exchanger, and a refrigeration cycle formed by a four-way valve that switches the connection between the refrigerant compressor and the indoor heat exchanger or the outdoor heat exchanger In the air conditioner, at startup of the air conditioner, after switching the four-way valve to the cooling operation side and the heating operation side for a predetermined time each, while switching the four-way valve to the cooling operation side or the heating operation side according to the operation mode thereafter, Since the compressor is driven, the pressure difference in the refrigeration cycle is completely eliminated at the time of driving the compressor, so that the compressor is not loaded by the pressure difference in the refrigeration cycle. .

[Brief description of drawings]

FIG. 1 is a system diagram of an air conditioner to which a drive control method of the present invention is applied.

FIG. 2 is a drive circuit diagram for realizing the drive control method of the present invention.

FIG. 3 is a timing chart for explaining the drive control method of the present invention.

[Explanation of symbols]

 1 Compressor 2 Four-way valve 3 Indoor heat exchanger 4 Decompressor 5 Outdoor heat exchanger

Claims (1)

[Claims] 1. A refrigerant compressor, an indoor heat exchanger, an outdoor heat exchanger, a pressure reducer interposed between the indoor heat exchanger and the outdoor heat exchanger, the refrigerant compressor and the In an air conditioner provided with a refrigeration cycle formed by a four-way valve that switches a connection method between an indoor heat exchanger and the outdoor heat exchanger, when the air conditioner is started, the four-way valve is set to a cooling operation side. After switching to the heating operation side for a predetermined time, the four-way valve is switched to the cooling operation side or the heating operation side according to the subsequent operation mode, and the compressor is driven, and the drive control method of the air conditioner. .