JP2664013B2 - Control method of air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling an air conditioner, and more particularly to a method for reducing a refrigerant noise during defrosting of an air conditioner having an "off" timer.

[0002]

2. Description of the Related Art Conventionally, in the defrosting of a heat pump type air conditioner, a compressor is stopped at the start of defrosting, and when the pressure on the discharge side of the compressor drops and the pressure difference falls below a certain value, a four-way valve is used. , And the compressor and the evaporator are reversed to operate the compressor to perform defrosting.However, if the time from the stop of the compressor to the switching of the four-way valve is not long enough, the pressure of the condenser and the evaporator will be reduced. The difference is large, and when the four-way valve is switched, the refrigerant rapidly flows through the four-way valve to generate a loud refrigerant noise, and there is a problem that the sleep is disturbed and the sleep is disturbed, especially at bedtime. However, if the time from the stop of the compressor to the switching of the four-way valve is taken long enough for this reason, the pressure difference between the condenser and the evaporator can be eliminated and the noise of the refrigerant can be prevented, but the air conditioner is completely stopped during that time. As a result, there is a problem that a comfortable indoor environment is impaired due to a delay in the start of defrosting and a change in room temperature during that time.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems. At least when a cut-off timer such as a "good-night timer" is set, the time from the stoppage of the compressor to the switching of the four-way valve is set. It is an object of the present invention to provide a method for controlling an air conditioner that sets a time longer than a predetermined time so as to reduce the refrigerant noise when the four-way valve is switched, does not hinder sleep, and does not impair indoor comfort.

[0004]

In order to achieve the above object, the time until the switching of the four-way valve at the start or end of defrosting is set to be longer than a predetermined time only when the off timer is set.

[0005]

According to the above arrangement, when the four-way valve is switched to start or end defrosting, only when the off timer is set,
The time from when the compressor stops to when the four-way valve is switched is longer than a predetermined time, and is set as the time until the difference in the refrigerant pressure is eliminated, so that the refrigerant generated due to the difference in the refrigerant pressure when switching the four-way valve. The sound can be prevented so as not to disturb sleep at bedtime.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing details of a refrigerant circuit of the present invention. A refrigerant circuit is formed by sequentially connecting a compressor 1, a four-way valve 2, an indoor heat exchanger 3, a capillary tube 4, and an outdoor heat exchanger 5. When cooling is set, the refrigerant gas compressed to a high temperature and a high pressure by the compressor 1 is sent to the outdoor heat exchanger 5 by the four-way valve 2, and is cooled by exchanging heat with outdoor air by the outdoor blower, and the capillary tube is cooled. 4, the indoor heat exchanger 3 removes heat from the indoor air by the indoor blower, cools the room and gasifies it, and the four-way valve 2
From the compressor to the suction side of the compressor 1. At the time of heating setting, the refrigerant gas compressed to a high temperature and a high pressure by the compressor 1 is switched by the four-way valve 2 so that the indoor heat exchanger 3
And heat exchanges with the indoor air by the indoor blower to heat the room. The cooled refrigerant gas is decompressed and liquefied by the capillary tube 4, and the heat is removed from the outdoor air by the outdoor heat exchanger 5 and the outdoor blower. The gas is robbed and circulated through a circuit returning from the four-way valve 2 to the suction side of the compressor 1.

FIG. 2 is a time chart showing the details of the present invention. When defrosting is performed at the time of cooling setting, when the compressor 1 is stopped, the high-pressure refrigerant gas in the outdoor heat exchanger 5 passes through the capillary tube 4 to perform indoor heat exchange. Flow into vessel 3 and gradually reduce the pressure
After a predetermined time elapses, the four-way valve 2
To return the high-pressure refrigerant in the outdoor heat exchanger 5 to the suction side of the compressor 1 via the four-way valve 2. Conventionally, the four-way valve 2 is switched in a state (a or c) where a pressure difference remains in the outdoor heat exchanger 5, and in this state, between the outdoor heat exchanger 5 and the indoor heat exchanger 3. Has a high pressure difference, and when the four-way valve 2 is switched, it flows rapidly through the four-way valve 2 to the suction side of the compressor 1 and generates a refrigerant noise due to the flow of the refrigerant in the four-way valve 2. In a daytime environmental condition, the refrigerant sound is not so disturbing, but the sound of the refrigerant may be harsh and hinder sleep at bedtime or during sleep. In the present invention, the switching of the four-way valve 2 is performed for a predetermined period of time only at bedtime until the pressure difference between the outdoor heat exchanger 5 and the indoor heat exchanger 3 disappears after the compressor 1 stops (b or d). By waiting for a longer time, generation of refrigerant noise is prevented. At the time of checking at bedtime, it is determined whether or not an off timer such as a “sleep timer” is set. Only when the timer is set, the four-way valve 2 is turned on until the pressure difference of the refrigerant gas is balanced. The switching time is delayed.

FIG. 3 is a flow chart showing the details of the present invention. When defrosting is started, the compressor 1 is stopped, the indoor blower and the outdoor blower are stopped at the same time, and a defrost display for instructing the start of defrosting is lit (display). twenty one). In this state, when the off timer is not operating (22), for example, it waits for 30 seconds to elapse (23). When the off timer is operating, it is confirmed that it is at bedtime and three minutes elapse. (24), the four-way valve 2 is switched (25) When 6 seconds have elapsed (26), the compressor 1 is started to start the defrosting operation (27), and when the defrost timer times out ( At 28), the compressor 1 is stopped (29), and when the off timer is not operating (30), it waits for 30 seconds to elapse (32). When the off timer is operating, it waits for 3 minutes. Stand by (31), switch the four-way valve 2 (33) When 6 seconds have elapsed (34), start the compressor 1, the outdoor blower, and the indoor blower (35), and turn off the defrost display (36). To return to operation. Above, the standby time raised as an example is a value uniquely determined by the design of the refrigerant circuit,
It shall be set by actual measurement using a model refrigerant circuit.

[0009]

As described above, in the present invention, the time from the stop of the compressor to the switching of the four-way valve only at the time of bedtime at the start of defrosting is determined until the refrigerant gas pressure in the refrigerant circuit is balanced. By setting the time longer than the time, it is possible to suppress the generation of the refrigerant noise at the start of defrosting and not to disturb the sleep at bedtime. Also, by determining whether or not it is at bedtime by whether or not the off timer is operating,
It is possible to prevent the generation of harsh refrigerant noises at bedtime.

[Brief description of the drawings]

FIG. 1 is a block diagram showing details of a refrigerant circuit of the present invention.

FIG. 2 is a time chart showing details of a control method of the present invention.

FIG. 3 is a flowchart showing details of a control method of the present invention.

FIG. 4 is a flowchart showing details of a conventional control method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Indoor heat exchanger 4 Capillary tube 5 Outdoor heat exchanger

Claims (1)

(57) [Claims] 1. A method for controlling an air conditioner, comprising: stopping operation of a compressor at the start or end of defrosting, switching a four-way valve after a lapse of a predetermined time until refrigerant pressure is stabilized, and starting operation of the compressor. A method of controlling the air conditioner, wherein the time until the switching of the four-way valve is set to be longer than a predetermined time at the start or end of defrosting only when the off timer is set.