Air Conditioner Performing Noise Prevention Control, and Control Method Therefor

This application is a continuation application, claiming priority under § 111 (a), of International Application No. PCT/KR2023/021832, filed on Dec. 28, 2023, which is based on and claims the benefit of Korean Patent Application No.: 10-2023-0005644, filed Jan. 13, 2023, in the Korean Intellectual Property Office, the disclosures of which are incorporated by reference herein in their entireties.

An embodiment of the present disclosure provides an air conditioner that performs noise prevention control, a method of controlling the air conditioner, and a computer-readable recording medium having recorded thereon a program for performing the method of controlling the air conditioner.

The air conditioner is equipped with a fan for discharging cooled air or heated air. The indoor unit of the air conditioner uses the fan to discharge the cooled air or heated air into an air conditioning space. More than a certain level of noise is accompanied by operation of the fan. The higher the revolution per minute (rpm) of the fan, the higher the noise level of the fan.

In the meantime, when the air conditioner is halted from an operation state, the rpm of the fan decreases to 0 from a certain value. In the case that the rpm of the fan decreases, an abrupt change in rpm causes significant reduction in noise level, and the significant change in noise level makes the user to perceive the noise. For example, when the air conditioner is halted at a reserved time in a sleep mode, the certain change in noise level may unpleasantly awake the user from his/her sleep.

According to an aspect of an embodiment of the present disclosure, provided is a method of controlling an air conditioner. A method of controlling an air conditioner includes receiving an off-control signal to terminate air conditioning operation of the air conditioner, determining whether the off-control signal to terminate the air conditioning operation is for immediately terminating a fan operation, based on determining that the off-control signal is for immediately terminating the fan operation, stopping a fan of the air conditioner by using a normal termination control, based on determining that the off-control signal is not for immediately terminating the fan operation, determining whether a fan operation termination condition is satisfied, and based on the fan operation termination condition being satisfied, stopping the fan of the air conditioner by using noise prevention control at a rate lower than a revolution per minute (rpm) reduction rate of the fan stopping by using the normal termination control.

According to an aspect of an embodiment of the present disclosure, provided also is an air conditioner. The air conditioner includes a fan. The air conditioner also includes a fan operation module for operating the fan. The air conditioner also includes an input interface. The air conditioner also includes a communication module. The air conditioner also includes a memory to store at least one instruction. The air conditioner also includes at least one processor. The at least one processor is configured to execute the at least one instruction to receive an off-control signal to terminate air conditioning operation through the communication module or the input interface, determine whether the off-control signal to terminate the air conditioning operation is for immediately terminating fan operation, based on determining that the off-control signal is for immediately terminating the fan operation, control the fan operation module to stop the fan by using normal termination control, based on determining that the off-control signal is not for immediately terminating the fan operation, determine whether a fan operation termination condition is satisfied, and based on the fan operation termination condition being satisfied, control the fan operation module to stop the fan by using noise prevention control at a rate lower than a revolution per minute (rpm) reduction rate of the fan stopping by using the normal termination control.

According to an embodiment of the present disclosure, provided is a computer-readable recording medium having recorded thereon a program to cause a computer to perform a method of controlling an air conditioner.

It is understood that various embodiments of the present specification and associated terms are not intended to limit technical features herein to particular embodiments, but encompass various changes, equivalents, or substitutions.

Like reference numerals may be used for like or related elements throughout the drawings.

The singular form of a noun corresponding to an item may include one or more items unless the context states otherwise.

Throughout the specification, “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may each include any one or all the possible combinations of A, B and C.

The expression “and/or” is interpreted to include a combination or any of associated elements.

Terms like “first”, “second”, etc., may be simply used to distinguish an element from another, without limiting the elements in a certain sense (e.g., in terms of importance or order).

When an element is mentioned as being “coupled” or “connected” to another element with or without an adverb “functionally” or “operatively”, it means that the element may be connected to the other element directly (e.g., wiredly), wirelessly, or through a third element.

It will be further understood that the terms “comprise” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, parts or combinations thereof, but do not preclude the possible presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

When an element is mentioned as being “connected to”, “coupled to”, “supported on” or “contacting” another element, it includes not only a case that the elements are directly connected to, coupled to, supported on or contact each other but also a case that the elements are connected to, coupled to, supported on or contact each other through a third element.

Throughout the specification, when an element is mentioned as being located “on” another element, it implies not only that the element is abut on the other element but also that a third element exists between the two elements.

An air conditioner according to various embodiments is a device for performing functions such as air purification, ventilation, humidity control, cooling or heating in an air conditioning space (hereinafter, referred to as a “room”), and refers to a device equipped with at least one of the functions.

In an embodiment, the air conditioner may include a heat pump device for performing the cooling function or the heating function. The heat pump device may include a refrigeration cycle in which a refrigerant is circulated along a compressor, a first heat exchanger, an expansion device and a second heat exchanger. All the components of the heat pump device may be built into a housing that forms the exterior of the air conditioner, and window fit air conditioners or portable air conditioners correspond to such an air conditioner. On the other hand, the components of the heat pump device may be distributed into multiple housings that form an air conditioner, which includes a wall-mounted air conditioner, a standing air conditioner, a system air conditioner, or the like.

The air conditioner including multiple housings may include at least one outdoor unit to be installed outdoors and at least one indoor unit to be installed indoors. For example, the air conditioner may be arranged such that one outdoor unit is connected to one indoor unit through a refrigerant pipe. For example, the air conditioner may be arranged such that one outdoor unit is connected to two or more indoor units through refrigerant pipes. For example, the air conditioner may be arranged such that two or more outdoor units are connected to two or more indoor units through multiple refrigerant pipes.

The outdoor unit may be electrically connected to the indoor unit. For example, information (or commands) for controlling the air conditioner may be input through an input interface arranged on the outdoor unit or the indoor unit, and in response to the user input, the outdoor unit and the indoor unit may be simultaneously or sequentially operated.

The air conditioner may include an outdoor heat exchanger arranged in the outdoor unit, an indoor heat exchanger arranged in the indoor unit, and a refrigerant pipe connecting the outdoor heat exchanger to the indoor heat exchanger.

The outdoor heat exchanger may perform heat exchange between the refrigerant and outdoor air by using a phase change of the refrigerant (e.g., evaporation or condensation). For example, the refrigerant may emit heat into the outdoor air while the refrigerant is being condensed in the outdoor heat exchanger, and the refrigerant may absorb heat from the outdoor air while the refrigerant flowing to the outdoor heat exchanger is being evaporated.

The indoor unit is arranged indoors. For example, the indoor unit may be classified into a ceiling-mounted indoor unit, a standing indoor unit, a wall-mounted indoor unit, or the like according to installation methods. For example, the ceiling-mounted indoor unit may be divided into a 4-way indoor unit, a 1-way indoor unit, a duct-type indoor unit, etc., according to air discharging methods.

Likewise, the indoor heat exchanger may perform heat exchange between the refrigerant and indoor air by using a phase change of the refrigerant (e.g., evaporation or condensation). For example, the refrigerant may absorb heat from the indoor air while being evaporated in the indoor unit, and the indoor air cooled while going through the cooled indoor heat exchanger may be blown to cool the room. Furthermore, the refrigerant may emit heat into the indoor air while being condensed in the indoor heat exchanger, and the indoor air heated while going through the hot indoor heat exchanger may be blown to heat the room.

That is, the air conditioner performs a cooling or heating function through a phase change process of the refrigerant that circulates the outdoor heat exchanger and the indoor heat exchanger, and for the circulation of the refrigerant, the air conditioner may include a compressor for compressing the refrigerant. The compressor may suck in refrigerant gas through a suction module and compress the refrigerant gas. The compressor may discharge high-temperature and high-pressure refrigerant gas through a discharger. The compressor may be arranged in the outdoor unit.

The refrigerant may circulate along the compressor, the outdoor heat exchanger, the expansion device and indoor heat exchanger in sequence through the refrigerant pipe, or circulate along the compressor, the indoor heat exchanger, the expansion device and the outdoor heat exchanger in sequence.

For example, the air conditioner may be configured so that the refrigerant is circulated between one outdoor unit and one indoor unit through the refrigerant pipe when the one outdoor unit is directly connected to the one indoor unit through the refrigerant pipe.

For example, when the air conditioner may have one outdoor unit connected to two or more indoor units through refrigerant pipes, the refrigerant may flow from the outdoor unit to the multiple indoor units through the refrigerant pipes branching from the outdoor unit. Refrigerants discharged from the multiple indoor units join and circulate to the outdoor unit. For example, the multiple indoor units may be connected to the one outdoor unit in parallel through the respective refrigerant pipes.

The multiple indoor units may each operate separately according to an operation mode set by the user. For example, some of the multiple indoor units may operate in a cooling mode while the others may operate in a heating mode. In this case, the refrigerant may selectively flow in a high-pressure or low-pressure state into each indoor unit along a designated circulation path through a flow path switching valve, which will be described later, and may be discharged and circulated into the outdoor unit.

For example, when the air conditioner has two or more outdoor units connected to two or more indoor units through multiple refrigerant pipes, refrigerants discharged from the multiple outdoor units may join and flow through one refrigerant pipe, may be divided again at a certain point and may flow into the multiple indoor units.

The multiple outdoor units may all be operated or at least some of them may not be operated depending on the operation load from an amount of operation of the multiple indoor units. In this case, the refrigerant may flow and circulate into an outdoor unit operated selectively through the flow path switching valve. The air conditioner may include an expansion device to reduce pressure of the refrigerant brought into the heat exchanger. For example, the expansion device may be arranged in the indoor unit or in the outdoor unit, or may be arranged in both of them.

The expansion device may lower the temperature and pressure of the refrigerant by using, for example, the throttling effect. The expansion device may include an orifice to reduce the cross-sectional area of the flow path. The refrigerant that has passed the orifice may have reduced temperature and pressure.

The expansion device may be implemented as an electronic expansion valve capable of controlling e.g., the opening ratio (a ratio of the cross-sectional area of the flow path of the valve in a partially open state to the cross-sectional area of the flow path of the valve in a fully open state). Depending on the opening ratio of the electronic expansion valve, the amount of refrigerant to pass the expansion device may be controlled.

The air conditioner may further include a flow path switching valve arranged in a refrigerant circulation flow path. The flow path switching valve may include, for example, a 4-way valve. The flow path switching valve may determine a circulation path of the refrigerant depending on the operation mode (e.g., cooling operation or heating operation) of the indoor unit. The flow path switching valve may be connected to a discharger of the compressor.

The air conditioner may include an accumulator. The accumulator may be connected to a suction module of the compressor. A low-temperature and low-pressure refrigerator evaporated from the indoor heat exchanger or the outdoor heat exchanger may flow into the accumulator.

When a refrigerant which is a mixture of a refrigerant liquid and a refrigerant gas flows into the accumulator, the accumulator may separate the refrigerant liquid from the refrigerant gas and provide the refrigerant gas from which the refrigerant liquid is separated to the compressor.

An outdoor fan may be arranged around the outdoor heat exchanger. The outdoor fan may blow outside air to the outdoor heat exchanger to promote heat exchange between the refrigerant and the outside air.

The outdoor unit of the air conditioner may include at least one sensor. For example, the sensor of the outdoor unit may be provided as an environmental sensor. The sensor of the outdoor unit may be arranged at a random position on the inside or outside of the outdoor unit. For example, the sensor of the outdoor unit may include, for example, a temperature sensor for detecting air temperature around the outdoor unit, a humidity sensor for detecting humidity around the outdoor unit, a refrigerant temperature sensor for detecting refrigerant temperature of a refrigerant pipe that passes through the outdoor unit, or a refrigerant pressure sensor for detecting refrigerant pressure of the refrigerant pipe that passes through the outdoor unit.

The outdoor unit of the air conditioner may include an outdoor unit communicator. The outdoor unit communicator may be arranged to receive a control signal from a controller of the indoor unit of the air conditioner, which will be described later. The outdoor unit may control an operation of the compressor, the outdoor heat exchanger, the expansion device, the flow path switching valve, the accumulator or the outdoor fan based on a control signal received through the outdoor unit communicator. The outdoor unit may transmit a sensing value detected from the outdoor unit sensor to the controller of the indoor unit through the outdoor unit communicator.

The indoor unit of the air conditioner may include a housing, a blower for circulating air into or out of the housing, and an indoor heat exchanger for exchanging heat with the air brought into the housing.

The housing may include a suction port. Indoor air may flow into the housing through the suction port.

The indoor unit of the air conditioner may include a filter arranged to filter out debris in the air brought into the housing through the suction port.

The housing may include a discharging port. The air moving in the housing may be discharged out of the housing through the discharging port.

An air flow guide may be arranged in the housing of the indoor unit to guide the direction of the air discharged through the discharging port. For example, the air flow guide may include a blade located at the discharging port. For example, the air flow guide may include an auxiliary fan for regulating the discharge airflow. It is not limited thereto, and the air flow guide may be omitted.

The indoor heat exchanger and the blower placed in a flow path connecting the suction port to the discharging port may be arranged in the housing of the indoor unit.

The blower may include an indoor fan and a fan motor. For example, the indoor fan may include an axial fan, a siroco fan, a crossflow fan, or a centrifugal fan.

The indoor heat exchanger may be arranged between the blower and the discharging port, or arranged between the suction port and the blower. The heat exchanger may absorb heat from the air brought in through the suction port or transmit heat to the air brought in through the suction port. The indoor heat exchanger may include a heat exchange tube in which the refrigerant flows, and a heat exchange fin that is in contact with the heat exchange tube to increase the heat transfer area.

The indoor unit of the air conditioner may include a drain tray arranged underneath the indoor heat exchanger to collect condensate water produced from the indoor heat exchanger. The condensate water received in the drain tray may be drained to the outside through a drain hose. The drain tray may be arranged to support the indoor heat exchanger.

The indoor unit of the air conditioner may include an input interface. The input interface may include a random type of user input module including buttons, switches, a touch screen and/or a touch pad. The user may input setting data (e.g., a desired indoor temperature, a cooling/heating/dehumidification/air purification operation mode setting, a discharge port selection setting and/or an air volume setting) through the input interface in person.