Noise reduction apparatus and air cleaner including same

Abstract

This air cleaner comprises: a housing having a flow path through which air can move; a fan operated such that the air can move through the flow path; and an air guide adjacent to the fan, wherein the air guide includes: a guide surface on which the air moving along the flow path flows while the fan is operated; and a sound absorption hole extending from the guide surface so as to absorb sound generated by the fan while the fan is operated.

Description

Noise reduction device and air purifier including same

[0001] The present invention relates to an air purifier. More specifically, the invention relates to an air purifier including a fan.

[0002] An air conditioner is a device that draws in indoor air, conditions it, and then expels it. Air conditioning, then, refers to the process of appropriately controlling indoor air temperature, humidity, cleanliness, and airflow distribution. Types of air conditioners include ventilation, air conditioners, air purifiers, and humidifiers.

[0003] An example of an air conditioner is an air purifier, a device used to control indoor air quality by removing airborne pollutants. Air purifiers can remove bacteria, viruses, mold, fine dust, and chemicals that cause odors from the inhaled air.

[0004] Air purifiers may include filters to purify polluted indoor air. Air drawn into the air purifier passes through the filter, removing contaminants and purifying the air. The purified air can then be discharged outside the air purifier. Recently, air conditioners, such as air conditioners, have also been equipped with filter units to perform air purification functions.

[0005] An air conditioner may include a fan to draw in and expel air. The fan may have a fan inlet, which is a passage through which air moves toward the fan.

[0006] The filter or filter unit and the fan inlet may have different cross-sections. To ensure that air is moved and energy loss is minimized, the flow adjacent to the filter and the flow adjacent to the fan inlet must have laminar motion.

[0007] Furthermore, the fan may generate noise while operating. This noise needs to be reduced.

[0008] One aspect of the present disclosure is to absorb sound generated while a fan is operating, thereby preventing unnecessary sound from being emitted outside the air purifier.

[0009] One aspect of the present disclosure is to provide an air purifier that reduces the noise generated by the fan while the fan is operating to move air, despite the movement of the air.

[0010] One aspect of the present disclosure is to provide an air purifier capable of absorbing sound generated during fan operation, including a noise reduction device having a meta structure, without using a thick sound-absorbing material.

[0011] One aspect of the present disclosure is to provide an air purifier capable of reducing noise without increasing the size of the housing by including an acceptable noise reduction device between the fan and the housing.

[0012] The technical problems to be achieved in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0013] Aspects of embodiments of the present disclosure will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of the embodiments presented.

[0014] According to one embodiment of the present disclosure, an air purifier includes a housing having a flow path through which air can move; a fan configured to allow air to move through the flow path when operated; and an air guide adjacent to the fan; wherein the air guide may include a guide surface configured to allow air moving along the flow path to flow while the fan is operated, and a sound-absorbing hole extending from the guide surface to absorb sound generated by the fan while the fan is operated.

[0015] According to one embodiment of the present disclosure, the air guide may include a guide portion including the guide surface and the sound-absorbing hole, and a space-forming portion defining a sound-insulating space between the guide portion and the guide portion. The guide surface may be provided on a side of the guide portion opposite to a side facing the sound-insulating space. The sound-absorbing hole may extend from the guide surface through the guide portion into the sound-insulating space.

[0016] According to one embodiment of the present disclosure, the volume of the sound-absorbing hole may be smaller than the volume of the sound-insulating space so as to prevent sound waves generated by the operation of the fan from traveling through the sound-absorbing hole in the sound-insulating space.

[0017] According to one embodiment of the present disclosure, the air guide has a resonant frequency defined by the sound-absorbing hole and the sound-insulating space, and when the frequency of the generated sound matches the resonant frequency of the air guide, the air guide can reduce the generated sound.

[0018] According to one embodiment of the present disclosure, the air guide may include a partition wall that divides the soundproof space into a first soundproof space and a second soundproof space having a different volume from the first soundproof space, and extends from the space forming portion toward the guide portion, a first soundproof unit that defines the first soundproof space and has a resonant frequency, and a second soundproof unit that defines the second soundproof space, the second soundproof unit having a resonant frequency different from the resonant frequency of the first soundproof unit.

[0019] According to one embodiment of the present disclosure, the sound-absorbing hole may be one of a plurality of first sound-absorbing holes and a plurality of second sound-absorbing holes. The plurality of first sound-absorbing holes may correspond to the first sound-blocking space. The plurality of second sound-absorbing holes may correspond to the second sound-blocking space. The number of sound-absorbing holes of the plurality of first sound-absorbing holes per volume of the first sound-blocking space may be different from the number of sound-absorbing holes of the plurality of second sound-absorbing holes per volume of the second sound-blocking space such that a resonant frequency of the first sound-blocking unit is different from a resonant frequency of the second sound-blocking unit.

[0020] According to one embodiment of the present disclosure, the sound-absorbing hole is one of a plurality of sound-absorbing holes, and the plurality of sound-absorbing holes may include a first sound-absorbing hole corresponding to the first sound-blocking space, and a second sound-absorbing hole corresponding to the second sound-blocking space. The diameter of the first sound-absorbing hole may be different from the diameter of the second sound-absorbing hole such that a resonant frequency of the first sound-blocking unit is different from a resonant frequency of the second sound-blocking unit.

[0021] According to one embodiment of the present disclosure, the diameter of the sound-absorbing hole may be less than 2.0 mm to prevent the generation of sound resonated by air moving along the path as the fan operates.

[0022] According to one embodiment of the present disclosure, the sound-absorbing hole can penetrate the guide portion so as to prevent a distance between two points on the opening of the sound-absorbing hole from becoming greater than 2.0 mm.

[0023] According to one embodiment of the present disclosure, the air guide may be configured to reduce sound in a frequency range of 1000 Hz or less among the frequencies of sound generated while the fan is operating. The air guide may have a meta-structure in which the density of air adjacent to the sound-absorbing hole has a negative value.

[0024] According to one embodiment of the present disclosure, the fan may have a fan inlet having a first cross-sectional area. A filter having a second cross-sectional area larger than the first cross-sectional area may be installed in the air purifier so as to be spaced apart from the fan. When the filter is installed in the air purifier, the guide part may include a guide path whose cross-sectional area decreases as it moves from the filter toward the fan inlet to prevent turbulence when air passing through the filter moves toward the fan inlet while the fan is operating.

[0025] According to one embodiment of the present disclosure, the fan may include a blade, a fan outlet, and a shroud between the blade and the air guide, the shroud extending radially from a center of rotation of the blade toward the fan outlet along a rotational axis of the blade. The air guide may include a flow guide passage having an increasingly larger cross-sectional area from an end of the guide passage toward the shroud, such that air is moved in an extension direction of the shroud when the fan is in operation.

[0026] According to one embodiment of the present disclosure, the sound-absorbing hole can correspond one-to-one with the sound-insulating space so that the air guide has a Helmholtz resonance structure.

[0027] According to one embodiment of the present disclosure, the length by which the soundproof space extends may be one-fourth of the wavelength of the generated sound.

[0028] According to one embodiment of the present disclosure, the air guide may be spaced radially with respect to the center of rotation of the fan and may extend circumferentially with respect to the center of rotation of the fan. The soundproof space may be between the air guide and the housing.

[0029] An air purifier according to one embodiment of the present disclosure may include a housing having an inlet and an outlet, a filter within the housing, a fan configured to move air from the filter to the outlet of the housing, the fan having a fan inlet through which air can pass and having a cross-sectional area smaller than a cross-sectional area of ​​the filter, and an air guide between the fan and the filter, the air guide having a guide path whose cross-sectional area becomes smaller toward the fan. The air guide may have a sound-absorbing hole that is configured to absorb sound generated when the fan is operated, and the sound-absorbing hole may be connected to a soundproof space.

[0030] A noise reduction device according to one embodiment of the present disclosure includes an air guide positionable adjacent to a fan, wherein the air guide may include a guide body, a soundproof space positioned inside the guide body, and a sound-absorbing hole that is open toward the fan to absorb sound generated when the fan or motor is operated, is communicated with the soundproof space, and has a volume smaller than the soundproof space.

[0031] These and / or other embodiments of the present disclosure will become apparent and more readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings.

[0032] FIG. 1 is a perspective view of an air purifier according to one embodiment of the present disclosure.

[0033] Figure 2 is an exploded view of the air purifier shown in Figure 1.

[0034] Fig. 3 is a cross-sectional view of the air purifier illustrated in Fig. 1.

[0035] Fig. 4 is a perspective view centered on the noise reduction device illustrated in Fig. 3.

[0036] Figure 5 is a perspective view illustrating the filter air guide illustrated in Figure 4.

[0037] Figure 6 is an enlarged cross-sectional perspective view showing the filter air guide shown in Figure 5 cut and enlarged.

[0038] Fig. 7 is an enlarged cross-sectional view showing the filter air guide shown in Fig. 5 cut and enlarged.

[0039] Fig. 8 is a conceptual diagram illustrating the principle of sound absorption in the filter air guide illustrated in Fig. 7.

[0040] Figure 9 is a cross-sectional view showing air flowing through the filter air guide illustrated in Figure 5.

[0041] Fig. 10 is a graph showing the noise reduction effect by the filter air guide shown in Fig. 9.

[0042] Fig. 11 is an enlarged cross-sectional view of a portion of the filter air guide illustrated in Fig. 9.

[0043] Fig. 12 is a perspective view illustrating the fan air guide illustrated in Fig. 4.

[0044] Figure 13 is an enlarged cross-sectional perspective view showing the fan air guide shown in Figure 12 cut and enlarged.

[0045] FIG. 14 is a cross-sectional view illustrating the fan air guide illustrated in FIG. 12 together with a configuration for noise reduction according to one embodiment of the present disclosure.

[0046] Figure 15 is a graph showing the sound absorption effect when the fan air guide illustrated in Figure 14 has a sound absorption hole with a diameter of 0.5 mm.

[0047] Figure 16 is a graph showing the sound absorption effect when the fan air guide illustrated in Figure 14 has a sound absorption hole with a diameter of 1.0 mm.

[0048] Figure 17 is a graph showing the sound absorption effect when the fan air guide illustrated in Figure 14 has a sound absorption hole with a diameter of 2.0 mm.

[0049] FIG. 18 is a cross-sectional view showing the filter air guide illustrated in FIG. 4 and the fan air guide and noise reduction configuration according to one embodiment of the present disclosure.

[0050] Figure 19 is a graph showing the noise reduction effect of the filter air guide and fan air guide shown in Figure 18 at the front of the air purifier.

[0051] Figure 20 is a graph showing the noise reduction effect of the filter air guide and fan air guide shown in Figure 18 at the rear of the air purifier.

[0052] FIG. 21 is a cross-sectional view of a filter air guide of an air purifier according to one embodiment of the present disclosure.

[0053] FIG. 22 is a cross-sectional view of a filter air guide of an air purifier according to one embodiment of the present disclosure.

[0054] FIG. 23 is an enlarged perspective view of a filter air guide of an air purifier according to one embodiment of the present disclosure.

[0055] Fig. 24 is a graph showing the noise reduction effect by the filter air guide shown in Fig. 23.

[0056] FIG. 25 is an enlarged perspective view of a filter air guide of an air purifier according to one embodiment of the present disclosure.

[0057] Fig. 26 is a graph showing the noise reduction effect by the filter air guide shown in Fig. 25.

[0058] It should be understood that the various embodiments and terms used in this document are not intended to limit the technical features described in this document to specific embodiments, but rather to include various modifications, equivalents, or substitutes of the embodiments.

[0059] In connection with the description of the drawings, similar reference numerals may be used for similar or related components.

[0060] The singular form of a noun corresponding to an item may include one or more of said items, unless the relevant context clearly indicates otherwise.

[0061] In this document, each of the phrases "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 include any one of the items listed together in that phrase, or all possible combinations thereof.

[0062] The term "and / or" includes any combination of a plurality of related described elements or any one of a plurality of related described elements.

[0063] Terms such as "first," "second," or "first" or "second" may be used simply to distinguish one component from another and do not qualify the components in any other respect (e.g., importance or order).

[0064] When a component (e.g., a first component) is referred to as being "coupled" or "connected" to another component (e.g., a second component), with or without the terms "functionally" or "communicatively," it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0065] The terms "include" or "have" are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in this document, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0066] When a component is said to be “connected,” “coupled,” “supported,” or “in contact with” another component, this includes not only cases where the components are directly connected, coupled, supported, or in contact, but also cases where the components are indirectly connected, coupled, supported, or in contact through a third component.

[0067] When a component is said to be "positioned on" another component, this includes not only cases where the component is in contact with the other component, but also cases where another component exists between the two components. The terms "upper-lower direction," "lower side," and "front-rear direction" used in the following description are defined based on the drawings, and these terms do not limit the shape and position of each component.

[0068] Specifically, as illustrated in Fig. 1, the direction in which the door of the air purifier (AL) faces is defined as forward, and the rear, left and right sides, and up and down sides can be defined based on this.

[0069] Furthermore, as illustrated in Fig. 1, the +X direction can be defined as forward, the +Y direction as left, and the +Z direction as upward.

[0070] In the present disclosure, “resonant frequency” may mean “natural frequency” or “natural frequency.”

[0071] The concepts of the present disclosure can be applied to air conditioners (AC). Although the drawings of the present disclosure illustrate an embodiment of an air purifier (AL), the concepts of the present disclosure can also be applied to air conditioners (AC).

[0072] Below, an embodiment of an air conditioner (AC) to which the principles of the present disclosure can be applied will first be described. After the description of the air conditioner (AC), an air purifier will be described as an embodiment of the present disclosure.

[0073] An air conditioner (AC) according to various embodiments is a device that performs functions such as air purification, ventilation, humidity control, cooling or heating in an air-conditioned space (hereinafter referred to as “indoor”), and means a device having at least one of these functions.

[0074] In one embodiment, an air conditioner (AC) may include a heat pump device to perform a cooling function or a heating function. The heat pump device may include a refrigeration cycle in which a refrigerant circulates along a compressor, a first heat exchanger, an expansion device, and a second heat exchanger. All components of the heat pump device may be housed in a single housing forming the exterior of the air conditioner (AC), such as a window air conditioner or a portable air conditioner. On the other hand, some components of the heat pump device may be housed separately in multiple housings forming a single air conditioner (AC), such as a wall-mounted air conditioner, a stand-alone air conditioner, and a system air conditioner.

[0075] An air conditioner (AC) including a plurality of housings may include at least one outdoor unit installed outdoors and at least one indoor unit installed indoors. For example, the air conditioner (AC) may be configured such that one outdoor unit and one indoor unit are connected via a refrigerant pipe. For example, the air conditioner (AC) may be configured such that one outdoor unit is connected to two or more indoor units via refrigerant pipes. For example, the air conditioner (AC) may be configured such that two or more outdoor units and two or more indoor units are connected via a plurality of refrigerant pipes.

[0076] The outdoor unit can be electrically connected to the indoor unit. For example, information (or commands) for controlling an air conditioner (AC) can be input through an input interface provided on either the outdoor or indoor unit, and the outdoor and indoor units can operate simultaneously or sequentially in response to user input.

[0077] An air conditioner (AC) may include an outdoor heat exchanger provided in an outdoor unit, an indoor heat exchanger provided in an indoor unit, and a refrigerant pipe connecting the outdoor heat exchanger and the indoor heat exchanger.

[0078] An outdoor heat exchanger can utilize a phase change (e.g., evaporation or condensation) of the refrigerant to exchange heat between the refrigerant and the outdoor air. For example, while the refrigerant condenses in the outdoor heat exchanger, it releases heat to the outdoor air, and while the refrigerant flowing in the outdoor heat exchanger evaporates, it absorbs heat from the outdoor air.

[0079] Indoor units are installed indoors. For example, indoor units can be categorized into ceiling-mounted, stand-alone, and wall-mounted types depending on their placement. For example, ceiling-mounted indoor units can be categorized into four-way, one-way, and duct-type indoor units depending on how air is discharged.

[0080] Similarly, an indoor heat exchanger can utilize the phase change of the refrigerant (e.g., evaporation or condensation) to exchange heat between the refrigerant and indoor air. For example, while the refrigerant evaporates in the indoor unit, the refrigerant can absorb heat from the indoor air. The cooled indoor air can then be blown through the cooled indoor heat exchanger, thereby cooling the room. Furthermore, while the refrigerant condenses in the indoor heat exchanger, the refrigerant can release heat to the indoor air. By blowing the heated indoor air through the high-temperature indoor heat exchanger, the room can be heated.

[0081] That is, an air conditioner (AC) performs a cooling or heating function through a phase change process of a refrigerant circulating between an outdoor heat exchanger and an indoor heat exchanger. To circulate the refrigerant, the air conditioner (AC) may include a compressor that compresses the refrigerant. The compressor can suck in refrigerant gas through an intake port and compress the refrigerant gas. The compressor can discharge high-temperature and high-pressure refrigerant gas through an exhaust port. The compressor may be placed inside the outdoor unit.

[0082] The refrigerant may circulate through the refrigerant pipes in the order of a compressor, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger, or in the order of a compressor, an indoor heat exchanger, an expansion device, and an outdoor heat exchanger.

[0083] For example, in an air conditioner (AC), if one outdoor unit and one indoor unit are directly connected through a refrigerant pipe, the refrigerant can be arranged to circulate between one outdoor unit and one indoor unit through the refrigerant pipe.

[0084] For example, in an air conditioner (AC), if one outdoor unit is connected to two or more indoor units via refrigerant pipes, the refrigerant can flow to multiple indoor units via refrigerant pipes branching from the outdoor unit. The refrigerant discharged from the multiple indoor units can be combined and circulated to the outdoor unit. For example, multiple indoor units can be directly connected in parallel to a single outdoor unit via separate refrigerant pipes.

[0085] Multiple indoor units can operate independently, each according to a user-defined operating mode. That is, some indoor units can operate in cooling mode, while others operate in heating mode. In this case, the refrigerant can be selectively introduced into each indoor unit at either high or low pressure along a designated circulation path via a flow-through valve, described later, and then discharged to the outdoor unit for circulation.

[0086] For example, when an air conditioner (AC) has two or more outdoor units and two or more indoor units connected through multiple refrigerant pipes, the refrigerant discharged from the multiple outdoor units may merge and flow through a single refrigerant pipe, then branch off at some point and flow into multiple indoor units.

[0087] Multiple outdoor units may be operated, or at least some may not be operated, depending on the operating load of the multiple indoor units. In this case, the refrigerant may be introduced into the outdoor unit, which is selectively operated, through a flow switching valve and circulated there. The air conditioner (AC) may include an expansion device to reduce the pressure of the refrigerant flowing into the heat exchanger. For example, the expansion device may be located within the indoor unit, the outdoor unit, or both.

[0088] An expansion device can, for example, utilize a throttling effect to lower the temperature and pressure of the refrigerant. The expansion device may include an orifice capable of reducing the cross-sectional area of ​​the flow path. Refrigerant passing through the orifice may experience a decrease in temperature and pressure.

[0089] The expansion device may be implemented as, for example, an electronic expansion valve capable of controlling the opening ratio (the ratio of the cross-sectional area of ​​the valve's flow path when partially open to the cross-sectional area of ​​the valve's flow path when fully open). Depending on the opening ratio of the electronic expansion valve, the amount of refrigerant passing through the expansion device can be controlled.

[0090] The air conditioner (AC) may further include a flow diverter valve positioned along the refrigerant circulation path. The flow diverter valve may include, for example, a four-way valve. The flow diverter valve may determine the refrigerant circulation path depending on the operating mode of the indoor unit (e.g., cooling operation or heating operation). The flow diverter valve may be connected to the discharge port of the compressor.

[0091] An air conditioner (AC) may include an accumulator. The accumulator may be connected to the suction side of the compressor. The accumulator may receive low-temperature, low-pressure refrigerant vaporized in an indoor heat exchanger or an outdoor heat exchanger.

[0092] The accumulator can separate the refrigerant liquid from the refrigerant gas when a refrigerant mixture of refrigerant liquid and refrigerant gas is introduced, and provide the refrigerant gas from which the refrigerant liquid has been separated to the compressor.

[0093] An outdoor fan may be installed near the outdoor heat exchanger. The outdoor fan may blow outdoor air to the outdoor heat exchanger to promote heat exchange between the refrigerant and the outdoor air.

[0094] An outdoor unit of an air conditioner (AC) may include at least one sensor. For example, the sensor of the outdoor unit may be provided as an environmental sensor. The outdoor unit sensor may be located at any location inside or outside the outdoor unit. For example, the outdoor unit sensor may include a temperature sensor for detecting air temperature around the outdoor unit, a humidity sensor for detecting air humidity around the outdoor unit, a refrigerant temperature sensor for detecting refrigerant temperature in a refrigerant pipe passing through the outdoor unit, or a refrigerant pressure sensor for detecting refrigerant pressure in a refrigerant pipe passing through the outdoor unit.

[0095] An outdoor unit of an air conditioner (AC) may include an outdoor unit communication unit. The outdoor unit communication unit may be configured to receive a control signal from a control unit of an indoor unit of the air conditioner (AC), which will be described later. The outdoor unit may control the operation of a compressor, an outdoor heat exchanger, an expansion device, a flow switching valve, an accumulator, or an outdoor fan based on the control signal received through the outdoor unit communication unit. The outdoor unit may transmit a sensing value detected by an outdoor unit sensor to the control unit of the indoor unit through the outdoor unit communication unit.

[0096] An indoor unit of an air conditioner (AC) may include a housing, a blower for circulating air into or out of the housing, and an indoor heat exchanger for exchanging heat with air flowing into the interior of the housing.

[0097] The housing may include an intake port through which indoor air may be drawn into the interior of the housing.

[0098] The indoor unit of an air conditioner (AC) may include a filter that is provided to filter foreign substances in the air that flows into the housing through an intake port.

[0099] The housing may include an exhaust port. Air flowing within the housing may be discharged to the exterior of the housing through the exhaust port.

[0100] The housing of the indoor unit may be provided with an airflow guide that guides the direction of air discharged through the exhaust port. For example, the airflow guide may include blades positioned above the exhaust port. For example, the airflow guide may include an auxiliary fan for controlling the exhaust airflow. However, the airflow guide is not limited thereto and may be omitted.

[0101] An indoor heat exchanger and a blower may be provided inside the housing of the indoor unit, which are arranged on a path connecting the intake and exhaust ports.

[0102] Blowers may include indoor fans and fan motors. For example, indoor fans may include axial fans, diffusion fans, crossflow fans, and centrifugal fans.

[0103] An indoor heat exchanger may be positioned between the blower and the exhaust, or between the intake and the blower. The indoor heat exchanger may absorb heat from air drawn in through the intake or transfer heat to the air drawn in through the intake. The indoor heat exchanger may include heat exchange tubes through which refrigerant flows, and heat exchange fins in contact with the heat exchange tubes to increase the heat transfer surface area.

[0104] The indoor unit of an air conditioner (AC) may include a drain tray positioned below the indoor heat exchanger to collect condensate generated in the indoor heat exchanger. The condensate collected in the drain tray may be drained to the outside via a drain hose. The drain tray may be configured to support the indoor heat exchanger.

[0105] An indoor unit of an air conditioner (AC) may include an input interface. The input interface may include any type of user input means, including buttons, switches, a touch screen, and / or a touch pad. A user can directly input setting data (e.g., desired indoor temperature, operating mode settings for cooling / heating / dehumidification / air purification, outlet selection settings, and / or air flow settings) through the input interface.

[0106] The input interface may also be connected to an external input device. For example, the input interface may be electrically connected to a wired remote controller. The wired remote controller may be installed at a specific location in an indoor space (e.g., a portion of a wall). A user may input configuration data regarding the operation of an air conditioner (AC) by operating the wired remote controller. Electrical signals corresponding to the configuration data obtained through the wired remote controller may be transmitted to the input interface. In addition, the input interface may include an infrared sensor. A user may remotely input configuration data regarding the operation of the air conditioner (AC) using a wireless remote controller. The configuration data input through the wireless remote controller may be transmitted to the input interface as an infrared signal.

[0107] Additionally, the input interface may include a microphone. A user's voice command may be acquired through the microphone. The microphone may convert the user's voice command into an electrical signal and transmit the converted electrical signal to an indoor unit control unit. The indoor unit control unit may control components of an air conditioner (AC) to execute a function corresponding to the user's voice command. Setting data acquired through the input interface (e.g., desired indoor temperature, operation mode settings for cooling / heating / dehumidification / air purification, outlet selection settings, and / or air volume settings) may be transmitted to the indoor unit control unit, which will be described later. In one example, the setting data acquired through the input interface may be transmitted externally, i.e., to an outdoor unit or a server, through an indoor unit communication unit, which will be described later.

[0108] An indoor unit of an air conditioner (AC) may include a power module. The power module can be connected to an external power source to supply power to components of the indoor unit.

[0109] An indoor unit of an air conditioner (AC) may include an indoor unit sensor. The indoor unit sensor may be an environmental sensor positioned within a space within or outside the housing. For example, the indoor unit sensor may include one or more temperature sensors and / or humidity sensors positioned within a predetermined space within or outside the housing of the indoor unit. For example, the indoor unit sensor may include a refrigerant temperature sensor for detecting a refrigerant temperature of a refrigerant pipe passing through the indoor unit. For example, the indoor unit sensor may include respective refrigerant temperature sensors for detecting the inlet, middle, and / or outlet temperatures of the refrigerant pipe passing through the indoor heat exchanger.

[0110] For example, each environmental information detected by an indoor unit sensor can be transmitted to the indoor unit control unit described later or transmitted externally through the indoor unit communication unit described later.

[0111] An indoor unit of an air conditioner (AC) may include an indoor unit communication unit. The indoor unit communication unit may include at least one of a short-range communication module and a long-range communication module. The indoor unit communication unit may include at least one antenna for wirelessly communicating with other devices. The outdoor unit may include an outdoor unit communication unit. The outdoor unit communication unit may also include at least one of a short-range communication module and a long-range communication module.

[0112] The short-range wireless communication module may include, but is not limited to, a Bluetooth communication module, a BLE (Bluetooth Low Energy) communication module, a near field communication module, a WLAN (Wi-Fi) communication module, a Zigbee communication module, an infrared (IrDA, infrared Data Association) communication module, a WFD (Wi-Fi Direct) communication module, an UWB (ultrawideband) communication module, an Ant+ communication module, a microwave (uWave) communication module, etc.

[0113] The remote communication module may include a communication module that performs various types of remote communication and may include a mobile communication unit. The mobile communication unit transmits and receives wireless signals with at least one of a base station, an external terminal, and a server on a mobile communication network.

[0114] The indoor unit communication unit can communicate with external devices such as servers, mobile devices, and other home appliances through a nearby access point (AP). The access point (AP) can connect a local area network (LAN) to which an air conditioner (AC) or a user device is connected to a wide area network (WAN) to which the server is connected. The air conditioner (AC) or the user device can be connected to the server through the wide area network (WAN). The indoor unit of the air conditioner (AC) may include an indoor unit control unit that controls components of the indoor unit, including a blower, etc. The outdoor unit of the air conditioner (AC) may include an outdoor unit control unit that controls components of the outdoor unit, including a compressor, etc. The indoor unit control unit can communicate with the outdoor unit control unit through the indoor unit communication unit and the outdoor unit communication unit. The outdoor unit communication unit can transmit a control signal generated by the outdoor unit control unit to the indoor unit communication unit, or can transmit a control signal transmitted from the indoor unit communication unit to the outdoor unit control unit. In other words, the outdoor unit and the indoor unit can communicate bidirectionally. The outdoor and indoor units can transmit and receive various signals generated during the operation of the air conditioner (AC).

[0115] The outdoor unit control unit can be electrically connected to components of the outdoor unit and can control the operation of each component. For example, the outdoor unit control unit can adjust the frequency of the compressor and control the flow switching valve to change the circulation direction of the refrigerant. The outdoor unit control unit can adjust the rotation speed of the outdoor fan. In addition, the outdoor unit control unit can generate a control signal to adjust the opening degree of the expansion valve. Under the control of the outdoor unit control unit, the refrigerant can circulate along a refrigerant circulation circuit including the compressor, the flow switching valve, the outdoor heat exchanger, the expansion valve, and the indoor heat exchanger.

[0116] The various temperature sensors included in the outdoor and indoor units can transmit electrical signals corresponding to the detected temperatures to the outdoor unit control unit and / or the indoor unit control unit. For example, the humidity sensors included in the outdoor and indoor units can transmit electrical signals corresponding to the detected humidity to the outdoor unit control unit and / or the indoor unit control unit.

[0117] The indoor unit control unit can obtain user input from a user device, including a mobile device, via the indoor unit communication unit, and can obtain user input directly through the input interface or via a remote controller. The indoor unit control unit can control components of the indoor unit, including a blower, in response to the received user input. The indoor unit control unit can transmit information regarding the received user input to the outdoor unit control unit of the outdoor unit.

[0118] The outdoor unit control unit can control the components of the outdoor unit, including the compressor, based on information regarding user input received from the indoor unit. For example, when a control signal corresponding to a user input for selecting an operation mode, such as cooling operation, heating operation, ventilation operation, defrosting operation, or dehumidification operation, is received from the indoor unit, the outdoor unit control unit can control the components of the outdoor unit so that the air conditioner (AC) performs an operation corresponding to the selected operation mode.

[0119] The outdoor unit control unit and the indoor unit control unit may each include a processor and a memory. The indoor unit control unit may include at least one first processor and at least one first memory, and the outdoor unit control unit may include at least one second processor and at least one second memory.

[0120] The memory can store / remember various information necessary for the operation of the air conditioner (AC). The memory can store instructions, applications, data, and / or programs necessary for the operation of the air conditioner (AC). For example, the memory can store various programs for the cooling, heating, dehumidifying, and / or defrosting operations of the air conditioner (AC). The memory can include volatile memory such as Static Random Access Memory (S-RAM) and Dynamic Random Access Memory (DRAM) for temporarily storing data. In addition, the memory can include nonvolatile memory such as Read Only Memory (ROM), Erasable Programmable Read Only Memory (EPROM), and Electrically Erasable Programmable Read Only Memory (EEPROM) for long-term storage of data.

[0121] The processor can generate control signals for controlling the operation of an air conditioner (AC) based on instructions, applications, data, and / or programs stored in memory. The processor, as hardware, may include logic circuits and arithmetic circuits. The processor can process data according to programs and / or instructions provided from memory and generate control signals based on the processing results. The memory and processor may be implemented as a single control circuit or as multiple circuits.

[0122] An indoor unit of an air conditioner (AC) may include an output interface. The output interface is electrically connected to an indoor unit control unit and can output information related to the operation of the air conditioner (AC) under the control of the indoor unit control unit. For example, information such as an operating mode selected by a user input, wind direction, wind volume, and temperature may be output. Additionally, the output interface may output sensing information obtained from an indoor unit sensor or an outdoor unit sensor, as well as warning / error messages.

[0123] The output interface may include a display and a speaker. The speaker, as an audio device, can output various sounds. The display may display information input by the user or information provided to the user using various graphic elements. For example, information regarding the operation of an air conditioner (AC) may be displayed as at least an image or text. The display may also include an indicator that provides specific information. The display may include a liquid crystal display panel (LCD), a light emitting diode panel (LED), an organic light emitting diode panel (OLED), a micro LED panel, and / or a plurality of LEDs.

[0124] Above, an air conditioner (AC) was described as an embodiment to which the principles of the present disclosure can be applied. Below, an air purifier (AL) is described as an embodiment to which the principles of the present disclosure can be applied. The air purifier (AL) can be included in the air conditioner (AC).

[0125] Hereinafter, embodiments according to the present invention will be described in detail with reference to the attached drawings.

[0126] FIG. 1 is a perspective view of an air purifier (AL) according to one embodiment of the present disclosure. FIG. 2 is an exploded view of the air purifier (AL) illustrated in FIG. 1. FIG. 3 is a cross-sectional view of the air purifier (AL) illustrated in FIG. 1.

[0127] Referring to FIGS. 1 to 3, an air purifier (AL) according to one embodiment of the present disclosure will be described.

[0128] When the air purifier (AL) is located indoors, the air in the indoors can be moved to the inside of the air purifier (AL), and after the air is purified, it can be moved to the outside of the air purifier (AL).

[0129] As illustrated in FIG. 1, the air purifier (AL) may include a housing (10). The housing (10) may be configured to form the exterior of the air purifier (AL).

[0130] The housing (10) may have an approximately rectangular parallelepiped shape. For aesthetic purposes, the housing (10) may have a substantially cuboid shape.

[0131] The housing (10) may be configured to form an inner space. A component for air purification may be arranged in the inner space of the housing (10). The housing (10) may protect the component for air purification to prevent impact from being applied to the component for air purification.

[0132] Air can be moved inside the housing (10), purified, and then moved outside the housing (10). The housing (10) can have a passage (10P) through which air can move. The air can move inside the housing (10) through the passage (10P) formed by the housing (10).

[0133] The housing (10) may be formed of plastic, but is not limited thereto.

[0134] The housing (10) can be formed by injection molding, but is not limited thereto.

[0135] The housing (10) may include a front panel (14). The front panel (14) may be positioned at the front of the housing (10). The front panel (14) may be configured to form a front appearance of the air cleaner (AL).

[0136] The front panel (14) may have a micro-discharge port (14H). The micro-discharge port (14H) may have a slit or hole. Air moved inside the air cleaner (AL) may move outside the air cleaner (AL) through the slit or hole of the front panel (14).

[0137] The front panel (14) may be configured to be spaced apart from a portion of the housing (10) and to form an opening or space communicating with the inside of the housing (10). Air may move into the inside of the housing (10) through the opening or space formed by the front panel (14).

[0138] A micro-ejection port (14H) having a slit or hole in the front panel (14) or an opening or space formed by the front panel (14) can be referred to as an outlet (12S).

[0139] The housing (10) may include a rear panel (15). The rear panel (15) may be positioned at the rear of the housing (10). The rear panel (15) may be configured to form a rear appearance of the air cleaner (AL).

[0140] The rear panel (15) may have a slit or hole. When air is to move inside the air cleaner (AL), it can move inside the air cleaner (AL) through the slit or hole of the rear panel (15).

[0141] The rear panel (15) may be configured to be spaced apart from a portion of the housing (10) and to form an opening or space communicating with the inside of the housing (10). Air may move into the inside of the housing (10) through the opening or space formed by the rear panel (15).

[0142] A slit, hole or opening or space formed by the rear panel (15) may be referred to as an inlet (11S).

[0143] Air is moved into the housing (10) through the inlet (11S) of the air purifier (AL), and the air moved into the housing (10) can be moved to the outside of the housing (10) through the outlet (12S) of the air purifier (AL). The inlet (11S) and the outlet (12S) may be formed on different surfaces, or may be formed on the same surface. The inlet (11S) may be formed on the rear end side of the housing (10). The outlet (12S) may be formed on the front end side of the housing (10).

[0144] The housing (10) may include a housing cover (13). The housing cover (13) may be configured to cover the upper, left, and right sides of the housing (10).

[0145] The housing cover (13) can be configured to define the appearance of the upper, left and right sides of the housing (10).

[0146] As described above, the inlet (11S) may be a space formed between the housing cover (13) and the rear panel (15). The outlet (12S) may be a space formed between the housing cover (13) and the front panel (14).

[0147] While the air purifier (AL) is not in operation, the front panel (14) and the rear panel (15) can be in contact with the housing cover (13). Accordingly, the inlet (11S) and the outlet (12S) may not be formed. While the air purifier (AL) is in operation, the front panel (14) and the rear panel (15) may be at least partially spaced from the housing cover (13). Accordingly, the inlet (11S) and the outlet (12S) may be formed. Accordingly, while the air purifier (AL) is not in operation, foreign substances may be prevented from entering the inside of the air purifier (AL), and while the air purifier (AL) is in operation, air may be allowed to enter the inside of the air purifier (AL) and to flow out of the outside of the air purifier (AL).

[0148] The front panel (14) can increase the size of the outlet (12S) when moved forward by a predetermined length. When the front panel (14) is moved forward by a predetermined length and then moved backward by a predetermined length, the size of the outlet (12S) can be reduced.

[0149] In other words, the outlet (12S) may correspond to the gap between the front panel (14) and the housing (10), and the outlet (12S) may become larger as the front panel (14) and the housing (10) become farther apart, and the outlet (12S) may become smaller as the front panel (14) and the housing (10) become closer to each other. When the front panel (14) and the housing (10) come into contact with each other, the outlet (12S) may be closed, and air may be discharged to the outside of the air purifier (AL) through a plurality of micro-outlets (14H) formed in the front panel (14). Since the area of ​​each of the plurality of micro-outlets (14H) is smaller than that of the outlet (12S), air passing through the micro-outlets (14H) may be discharged at a lower speed than air passing through the outlet (12S).

[0150] However, this is not limited thereto. The front panel (14) may be fixedly fixed to the front of the housing (10), and the outlet (12S) may be formed in the front panel (14) or the housing (10). The front panel (14) and the housing (10) may be provided as one piece.

[0151] When the air cleaner (AL) is placed on the floor, the housing cover (13) can define the appearance of the air cleaner (AL) together with the front panel (14) and the rear panel (15).

[0152] The housing (10) may include a lower panel (16). The lower panel (16) may be positioned on the lower side of the housing (10). The lower panel (16) may define the lower exterior of the air cleaner (AL).

[0153] As illustrated in FIG. 3, the air purifier (AL) may include a filter assembly (FS). The filter assembly (FS) may be configured to purify air as it passes through the filter assembly (FS).

[0154] The filter assembly (FS) can be positioned inside the housing (10). The filter assembly (FS) can be detachably mounted to the housing (10).

[0155] The filter assembly (FS) may be configured to allow air to pass through. As the air passes through, foreign substances contained in the air may be adsorbed on the filter assembly (FS).

[0156] The air cleaner (AL) may include a fan assembly (FA). The fan assembly (FA) may be operated to move air.

[0157] The fan assembly (FA) may be positioned inside the housing (10). The fan assembly (FA) may be detachably mounted to the housing (10).

[0158] The fan assembly (FA) can cause air to move into the housing (10) or out of the housing (10). When the fan assembly (FA) is operating, air flows, and upstream and downstream can be defined by the flowing air.

[0159] The fan assembly (FA) may have a fan inlet (100Aa). The fan inlet (100Aa) may be an opening through which air enters the fan assembly (FA).

[0160] The fan inlet (100Aa) may have a circular shape.

[0161] The fan assembly (FA) may have a fan outlet (100Ab). The fan outlet (100Ab) may be an opening through which air exits the fan assembly (FA).

[0162] Based on the fan inlet (100Aa), the air moving toward the fan inlet (100Aa) can be defined as upstream, and the air moving away from the fan inlet (100Aa) can be defined as downstream. Based on the fan outlet (100Ab), the air moving toward the fan outlet (100Ab) can be defined as upstream, and the air moving away from the fan outlet (100Ab) can be defined as downstream. However, this is not limited thereto, and upstream and downstream can be defined to refer to different parts depending on the flow of air at a certain point.

[0163] The filter assembly (FS) may be positioned upstream of the fan assembly (FA). Accordingly, air sucked from the inlet (11S) by the fan assembly (FA) may pass through the filter assembly (FS) and move toward the fan assembly (FA). The fan assembly (FA) may move the air toward the outlet (12S).

[0164] More specifically, air passes through the filter assembly (FS) and moves inside the fan assembly (FA) toward the fan inlet (100Aa) of the fan assembly (FA), and the air moved inside the fan assembly (FA) can move toward the outlet (12S) of the housing (10) through the fan outlet (100Ab).

[0165] The filter assembly (FS) may be positioned adjacent to the fan assembly (FA). The fan assembly (FA) may cause air flow. Since air passing through the filter assembly (FS) experiences a pressure loss, it may be desirable for the air passing through the filter assembly (FS) to have a fast flow so that the air can be moved despite the pressure loss. Therefore, it may be desirable for the filter assembly (FS) to be positioned adjacent to the fan assembly (FA).

[0166] However, the filter assembly (FS) may need to be spaced apart from the fan assembly (FA) by a certain distance. This is because the cross-sectional area of ​​the filter assembly (FS) with respect to the direction of air flow may be different from the cross-sectional area of ​​the fan inlet (100Aa) of the fan assembly (FA). If the cross-sectional areas are different, the air may have to swirl rather than move straight from the filter assembly (FS) toward the fan inlet (100Aa) of the fan assembly (FA) while moving. In this case, if there is not enough space to swirl, the air may move turbulently rather than laminarly. If the air moves turbulently, energy loss occurs due to friction, which may mean that the air does not move smoothly. Since the smooth movement of the air can define the amount of air that the air purifier (AL) can filter (200) over time, it is necessary to prevent the air from moving turbulently.

[0167] For this purpose, the filter assembly (FS) may be spaced apart from the fan assembly (FA) by a predetermined distance. For example, the cross-sectional area of ​​the filter assembly (FS) may be larger than the cross-sectional area of ​​the fan inlet (100Aa) of the fan assembly (FA), and the filter assembly (FS) may be positioned spaced apart from the rear of the fan assembly (FA).

[0168] In addition to the feature that the filter assembly (FS) and the fan assembly (FA) are positioned separately, this embodiment further describes the air guide (AG).

[0169] The air cleaner (AL) may include an air guide (AG). The air guide (AG) may refer to a configuration configured to guide the movement of air while the fan assembly (FA) is in operation.

[0170] The air guide (AG) may be adjacent to the fan assembly (FA).

[0171] The air guide (AG) may include a filter air guide (300) and a fan air guide (300-1).

[0172] Here, the filter air guide (300) may be referred to as a first air guide (AG). The fan air guide (300-1) may be referred to as a second air guide (AG).

[0173] The filter air guide (300) can be positioned between the filter assembly (FS) and the fan assembly (FA).

[0174] The filter air guide (300) can guide air so that air passing through the filter assembly (FS) moves to the fan inlet (100Aa) of the fan assembly (FA).

[0175] The air guide (AG) may have a guide path (310P). The guide path (310P) may be a path (10P) formed to allow air to move by the air guide (AG). The guide path (310P) may include a first air guide path (310Pa) of the filter air guide (300).

[0176] The first air guide passage (310Pa) can pass through the filter air guide (300). Air passing through the filter assembly (FS) can pass through the first air guide passage (310Pa) and move toward the fan inlet (100Aa) of the fan assembly (FA).

[0177] The first air guide passage (310Pa) may be provided so that the cross-sectional area on the side facing the filter assembly (FS) is identical to or similar to the cross-sectional area of ​​the filter assembly (FS). The first air guide passage (310Pa) may be provided so that the cross-sectional area on the side facing the fan assembly (FA) is identical to or similar to the cross-sectional area of ​​the fan inlet (100Aa). As illustrated in FIG. 3, when the cross-sectional area of ​​the filter assembly (FS) is larger than the cross-sectional area of ​​the fan inlet (100Aa), the first air guide passage (310Pa) may be configured to become narrower from the filter assembly (FS) to the fan inlet (100Aa).

[0178] The first air guide path (310Pa) may be formed by a smooth curved surface to prevent turbulence while the air moves through the first air guide path (310Pa).

[0179] The first air guide path (310Pa) may be positioned at the center of the filter air guide (300). The first air guide path (310Pa) may have a shape that is rotationally symmetrical about the axis. The first air guide path (310Pa) may have a circular cross-section and may extend about the axis.

[0180] The fan inlet (100Aa) may have a circular shape. The center of the circle of the fan inlet (100Aa) may be aligned with the axis of the first air guide passage (310Pa). The center of the circle of the fan inlet (100Aa) may be located on the rotation axis of the fan (100). Accordingly, the axis of the first air guide passage (310Pa) may be aligned with the rotation axis of the fan inlet (100Aa).

[0181] The first air guide path (310Pa) may have a cross-section of a circle whose shape corresponds to the fan inlet (100Aa) as it moves toward the fan inlet (100Aa). If the cross-sectional area of ​​the filter (200) is large, the first air guide path (310Pa) may have a cross-section of a circle whose area becomes smaller as it moves from the filter (200) toward the fan inlet (100Aa).

[0182] In other words, the fan (100) may have a fan inlet (100Aa) having a first cross-sectional area. The fan (100) may include a filter (200) spaced apart from the fan (100) and having a second cross-sectional area larger than the first cross-sectional area.

[0183] The guide section (310) may include a guide path (310P) whose cross-sectional area decreases as it moves from the filter (200) toward the fan inlet (100Aa) to prevent turbulence from occurring when the air passing through the filter (200) moves toward the fan inlet (100Aa) while the fan (100) is operating.

[0184] The filter air guide (300) may be formed of plastic, but is not limited thereto.

[0185] The filter air guide (300) may be formed by injection molding, but is not limited thereto.

[0186] The fan air guide (300-1) may be positioned on the outside of the fan assembly (FA). The fan air guide (300-1) may be positioned so as to be spaced radially outward from the center of rotation of the fan (100) of the fan assembly (FA).

[0187] The fan air guide (300-1) may be configured to surround at least a portion of the fan assembly (FA). The fan air guide (300-1) may include a portion extending from a position adjacent to an outlet of the fan assembly (FA) in a direction from the fan outlet (100Ab) toward the outlet (12S) of the housing (10).

[0188] For example, the fan air guide (300-1) may have a bell shape. The fan assembly (FA) may be positioned inside the bell-shaped fan air guide (300-1). Air moved by the fan air guide (300-1) may move along the inner wall of the bell-shaped fan air guide (300-1) toward the bell-shaped opening.

[0189] The fan air guide (300-1) can guide air so that air moves from the fan outlet (100Ab) toward the outlet (12S) of the housing (10) by the fan assembly (FA).

[0190] The guide path (310P) may include a second air guide path (310Pb) of the fan air guide (300-1). The second air guide path (310Pb) may pass through the fan air guide (300-1). Air that passes through the fan assembly (FA) and the fan outlet (100Ab) may move along the second air guide path (310Pb) to the outlet (12S) of the housing (10).

[0191] The second air guide path (310Pb) may be formed by the fan air guide (300-1) and the fan assembly (FA). The fan air guide (300-1) may be configured to extend forward. The outlet (12S) of the housing (10) may be positioned in front of the filter air guide (300).

[0192] The second air guide euro (310Pb) can extend from the fan outlet (100Ab) to a position covered by the filter air guide (300).

[0193] The air moved toward the fan assembly (FA) can pass through the second air guide path (310Pb) and move toward the outlet (12S) of the housing (10).

[0194] The cross-sectional area of ​​the fan air guide (300-1) may increase toward the outlet (12S) of the housing (10). The cross-sectional area of ​​the second air guide path (310Pb) may increase toward the outlet (12S) of the housing (10). When the cross-sectional area of ​​the second air guide path (310Pb) increases, the speed of the air may decrease as it moves toward the outlet (12S) of the housing (10).

[0195] The air cleaner (AL) may have an outlet path (12P). The outlet path (12P) may be a path (10P) extending from the second air guide path (310Pb) to the outlet (12S). The outlet path (12P) may be defined by an edge panel (14a) forming an inner wall located inside the housing (10) described below.

[0196] Below is a description of the configurations that the configuration described above may include.

[0197] A fan assembly (FA) may include a fan (100).

[0198] The fan (100) may have a rotation axis (R) parallel to the front-back direction. The fan (100) may include a hub coupled to the shaft (121), a plurality of blades (110), and a shroud (120) in which a fan inlet (100Aa) connected to the plurality of blades (110) and configured to suck in air from the rear is formed. The fan inlet (100Aa) may be opened toward the rear. The fan inlet (100Aa) may be formed in a circular shape. The fan (100) may discharge air toward the front. The fan (100) may include a diffusion fan (100). The fan (100) may include a turbofan (100).

[0199] The fan assembly (FA) may include a fan motor (130).

[0200] The fan motor (130) can provide driving force to the fan (100) so that the blades (110) of the fan (100) rotate. The fan motor (130) can include a motor shaft. The motor shaft can extend in the forward and backward direction. The motor shaft can be coupled to the fan (100) to transmit the power of the fan motor (130) to the fan (100).

[0201] The fan motor (130) can be controlled by a control unit (not shown). The control unit can include a processor and memory.

[0202] The processor can receive a signal from the input unit and operate or stop the fan motor (130). Since the blade (110) of the fan (100) can be rotated by the operation of the fan motor (130), the blade (110) of the fan (100) can be rotated by the processor.

[0203] At this time, the rotation of the blade (110) of the fan (100) can be said to indicate that the fan (100) is operating. The operation of the fan (100) can mean the operation of the fan motor (130). The operation of the fan motor (130) can mean that the motor shaft is rotating.

[0204] A filter assembly (FS) may include a filter (200). The filter (200) may have a mesh filter (200). The filter (200) may have a plurality of gaps. As air passes through the plurality of gaps, foreign substances mixed in the air may be filtered (200).

[0205] Refer to Fig. 2 to illustrate another configuration of the air purifier (AL).

[0206] As illustrated in FIG. 2, the air cleaner (AL) may include a front panel (14). The air cleaner (AL) may include an edge panel (14a) positioned at the rear of the front panel (14) and adjacent to an edge of the front panel (14). The edge panel (14a) may extend along a direction in which the edge of the front panel (14) extends.

[0207] The air cleaner (AL) may include a fan assembly (FA) positioned at the rear of the front panel (14).

[0208] The air cleaner (AL) may include a blower case (101) in which a fan assembly (FA) is mounted. The blower case (101) may form an inner wall of the air cleaner (AL).

[0209] The air cleaner (AL) may include a fan air guide (300-1) mounted on the blower case (101) by moving from the rear to the front of the blower case (101). The fan air guide (300-1) may be included in the air guide (AG). The fan air guide (300-1) may be positioned to surround the fan (100). When the fan air guide (300-1) is mounted on the blower case (101), at least a portion of the fan air guide (300-1) may be positioned on the front of the blower case (101).

[0210] The air purifier (AL) may include a guide case (401) mounted on the blower case (101). The guide case (401) may be moved from the rear of the blower case (101) toward the blower case (101) and mounted on the blower case (101).

[0211] The air purifier (AL) may include a filter air guide (300). The filter air guide (300) may be located at the rear of the guide case (401). The filter air guide (300) may be mounted on the blower case (101) and the guide case (401).

[0212] The air purifier (AL) may include a filter case (201) at least partially positioned between the filter air guide (300) and the filter assembly (FS). The filter case (201) may accommodate the filter assembly (FS).

[0213] The air purifier (AL) may include a filter assembly (FS) mounted in a filter case (201).

[0214] The air cleaner (AL) may include a rear panel (15) positioned at the rear of the filter assembly (FS).

[0215] As illustrated in Fig. 3, air can be moved from the inlet (11S) toward the outlet (12S). In Fig. 3, solid arrows indicate the flow of air, and dotted arrows indicate the flow of sound. A configuration capable of reducing noise generated while air is moved is described below.

[0216] Fig. 4 is a perspective view centered on the noise reduction device illustrated in Fig. 3.

[0217] Referring to FIG. 4, a noise reduction device according to one embodiment of the present disclosure is described.

[0218] The air guide (AG) was previously described. A device capable of reducing the volume of sound, such as the air guide (AG) described in one embodiment of the present disclosure, may be referred to as a noise reduction device. Accordingly, an air purifier (AL) may include a noise reduction device. The noise reduction device may include an air guide (AG).

[0219] However, the noise reduction device of the present disclosure is shown and described as being used as part of an air cleaner (AL), but such a noise reduction device is not limited to an air cleaner (AL). The noise reduction device can reduce sound when positioned adjacent to a component that can generate sound.

[0220] For convenience of explanation, this document assumes that the noise reduction device is part of an air cleaner (AL).

[0221] The noise reduction device may be adjacent to the fan (100) or the fan motor (130). The noise reduction device may be configured to reduce sound generated by the fan (100) or the fan motor (130).

[0222] The fan motor (130) may include a rotor and a stator. Since the rotor rotates relative to the stator, sound may be generated while the rotor rotates. Furthermore, the fan (100) may be rotated by the motor. While the fan (100) rotates, sound may be generated due to vibrations generated when the blades (110) come into contact with the air. In response to such sound, a noise reduction device may reduce the sound generated by the fan (100) and the fan motor (130).

[0223] The noise reduction device may include an air guide (AG). The air guide (AG) may be configured to guide air moved by the fan (100). At the same time, the air guide (AG) may reduce the level of sound while the air flows along the surface of the air guide (AG).

[0224] The air guide (AG) may include a guide portion (310) having a guide surface (310A) along which air flows. The air may move along the guide portion (310) along a path (10P) within the housing (10). The guide portion (310) may form the guide path (310P) described above.

[0225] The guide portion (310) may include a first air guide portion (310a) included in the filter air guide (300). The first air guide portion (310a) may have an opening defined by a cross-section relative to the rotational axis of the fan (100) that becomes narrower as it moves toward the fan inlet (100Aa).

[0226] The guide surface (310A) may include a first air guide surface (310Aa) included in the filter air guide (300). The first air guide portion (310a) may have a first air guide surface (310Aa).

[0227] The guide portion (310) may include a second air guide portion (310b) included in the fan air guide (300-1). The second air guide portion (310b) may have an opening defined by a cross-section relative to the rotational axis of the fan (100) that becomes wider as it moves toward the outlet (12S) of the housing (10).

[0228] The guide surface (310A) may include a second air guide surface (310Ab) included in the filter air guide (300). The second air guide portion (310b) may have a second air guide surface (310Ab).

[0229] In other words, air can be moved along the guide portion (310). In order to reduce the sound of the fan (100) that moves the air, the air guide (AG) may include the following configuration.

[0230] The air guide (AG) may have a sound-absorbing hole (310H). The sound-absorbing hole (310H) may be formed to penetrate the guide portion (310). The sound-absorbing hole (310H) may extend from the guide surface (310A). The sound-absorbing hole (310H) may extend from the guide surface (310A) through the guide portion (310) to a sound-insulating space (320S) described below. The sound-absorbing hole (310H) may reduce sound generated from the fan (100) or the fan motor (130) together with the sound-insulating space (320S) described below.

[0231] However, even if only a sound-absorbing hole (310H) is provided without a soundproof space (320S), sound can be reduced. This will be described in detail in the relevant section with reference to Fig. 8.

[0232] The sound-absorbing hole (310H) may include a first air guide sound-absorbing hole (310Ha) of the filter air guide (300). The first air guide portion (310a) may have a first air guide sound-absorbing hole (310Ha).

[0233] The sound-absorbing hole (310H) may include a second air guide sound-absorbing hole (310Hb) of the fan air guide (300-1). The second air guide portion (310b) may have a second air guide sound-absorbing hole (310Hb).

[0234] Referring to FIG. 3, the air guide (AG) can define a soundproof space (320S). The guide portion (310) can be configured to form a soundproof space (320S) that is in communication with the sound-absorbing hole (310H).

[0235] The soundproof space (320S) may include a first air guide soundproof space (320Sa) defined by the first air guide (AG).

[0236] The soundproof space (320S) may include a second air guide soundproof space (320Sb) defined by a second air guide (AG).

[0237] The air guide (AG) may include an air guide mounting portion (301) for mounting to a peripheral configuration.

[0238] The air guide mounting portion (301) may include a first air guide mounting portion (301a) included in the first air guide (AG). The first air guide mounting portion (301a) may protrude from the outside of the air guide (AG). The first air guide mounting portion (301a) may extend in the direction in which the first air guide (AG) is mounted. The first air guide mounting portion (301a) may extend in the front-back direction. There may be a plurality of first air guide mounting portions (301a).

[0239] The air guide mounting portion (301) may include a second air guide mounting portion (301b) included in the second air guide (AG). The second air guide mounting portion (301b) may protrude from the outside of the air guide (AG).

[0240] Fig. 5 is a perspective view illustrating the filter air guide (300) illustrated in Fig. 4. Fig. 6 is an enlarged cross-sectional perspective view illustrating the filter air guide (300) illustrated in Fig. 5 cut and enlarged.

[0241] Referring to FIGS. 5 and 6, the structure of a filter air guide (300) according to one embodiment of the present disclosure is described.

[0242] The filter air guide (300) may include a soundproof space (320S). The first air guide portion (310a) included in the filter air guide (300) may be expressed as a guide portion (310) included in the filter air guide (300). The first air guide path (310Pa) may be expressed as a guide path (310P) included in the filter air guide (300). The first air guide sound-absorbing hole (310Ha) may be expressed as a sound-absorbing hole (310H) included in the filter air guide (300). The first air guide sound-absorbing space (320Sa) may be expressed as a sound-absorbing space (320S) included in the filter air guide (300).

[0243] The reason why the expressions can be substituted as above is because the idea applied to the filter air guide (300) can also be applied to the fan air guide (300-1). Therefore, for convenience of expression, the name of the configuration included in the filter air guide (300) can be expressed as the name of the configuration included in the air guide (AG).

[0244] The filter air guide (300) may include a space forming portion (320) defining a soundproof space (320S). The space forming portion (320) may extend from the guide portion (310) and surround the soundproof space (320S) together with the guide portion (310). The space forming portion (320) may be positioned in front of the guide portion (310). The space forming portion (320) may be bent forward from an edge of the guide portion (310) and extended, and then bent again to extend toward the guide path (310P). The space forming portion (320) may extend from the guide portion (310) to define a soundproof space (320S) between the guide portion (310) and the space forming portion (320). The soundproof space (320S) may be defined by a surface of the guide portion (310) opposite to the guide surface (310A) and the space forming portion (320). However, the soundproof space (320S) may be located not only below the guide part (310), but also adjacent to the guide part (310).

[0245] For example, as shown in FIG. 6, when looking at the soundproof space (320S) located at the lower side, the space forming part (320) may extend forward from the lower side of the guide part (310), be bent at the end, and extend upward again.

[0246] The filter air guide (300) may include a guide body (310, 320). The guide body (310, 320) may include a guide portion (310) or a space forming portion (320). The fan air guide (300-1) may include a guide body (310, 320). The guide body (310, 320) of the fan air guide (300-1) may include a guide portion (310). The air guide (AG) may include a guide body (310, 320).

[0247] The space forming part (320) can form a soundproof space (320S).

[0248] The soundproof space (320S) may be in communication with the sound-absorbing hole (310H). Since the soundproof space (320S) may be adjacent to the guide portion (310), the soundproof space (320S) may be positioned adjacent to the sound-absorbing hole (310H). The soundproof space (320S) may be in communication with the outside of the filter air guide (300) through the sound-absorbing hole (310H).

[0249] The volume of the soundproof space (320S) may be larger than the volume of the sound-absorbing hole (310H).

[0250] The sound volume can be reduced by the sound-absorbing hole (310H) and the sound-insulating space (320S).

[0251] Sound is a vibration of air. Air vibrations can have wave properties. That is, sound can be a sound wave. Therefore, sound can have both frequency and wavelength.

[0252] A certain space can be defined by the sound-absorbing hole (310H). The space defined by the sound-absorbing hole (310H) may refer to the space inside the sound-absorbing hole (310H). Since the sound-absorbing hole (310H) has an empty space, the resonance frequency of the guide part (310) or the filter air guide (300) can be changed.

[0253] The resonance frequency of the guide portion (310) or the filter air guide (300) can be defined by the formation of the sound-absorbing hole (310H). This is because the sound-absorbing hole (310H) forms an empty space, thereby defining the shape of the guide portion (310) or the filter air guide (300).

[0254] When sound waves encounter a structure with a matching resonant frequency, they tend to be absorbed by that structure. Therefore, by adjusting the shape, number, diameter, etc. of the sound-absorbing holes (310H), the sound waves to be absorbed by the guide unit (310) or the air guide (AG) can be targeted. For example, as illustrated in the drawings, the sound-absorbing holes (310H) may have a cylindrical shape with a circular cross-section. For example, the sound-absorbing holes (310H) may also have a polygonal columnar shape with a polygonal cross-section such as a triangle or square.

[0255] Below, the principle of sound absorption by the sound-absorbing hole (310H) is described in detail with reference to FIG. 7 or FIG. 8.

[0256] The principle of sound absorption by the sound-absorbing hole (310H) can also be applied to the soundproof space (320S).

[0257] For example, the soundproof space (320S) and the sound-absorbing hole (310H) can be considered to correspond to the flask. The part corresponding to the narrow entrance of the flask can be referred to as the sound-absorbing hole (310H). The part corresponding to the wide space inside the flask can be referred to as the soundproof space (320S).

[0258] When sound waves enter the soundproof space (320S) through the sound-absorbing hole (310H), the volume of the soundproof space (320S) is large compared to the entrance diameter of the sound-absorbing hole (310H), so it may be difficult for the sound waves to escape from the soundproof space (320S) through the sound-absorbing hole (310H).

[0259] The smaller the diameter of the sound-absorbing hole (310H), the less sound may be emitted outside the air purifier (AL). This is because the sound-absorbing hole (310H) may be an outlet configured to allow sound waves to exit from the sound-insulating space (320S) to the outside of the sound-insulating space (320S).

[0260] The larger the volume of the soundproof space (320S), the better the sound waves can be received into the soundproof space (320S). Therefore, the volume of the soundproof space (320S) can determine the degree of sound absorption.

[0261] As described above, the sound-absorbing hole (310H) can define the resonance frequency of the filter air guide (300). The sound-insulating space (320S) can also define the resonance frequency of the filter air guide (300). This is because the sound-insulating space (320S) is an empty space and thus can define the shape of the filter air guide (300).

[0262] That is, the soundproof space (320S) can determine the frequency of sound waves to be absorbed by the filter air guide (300). In other words, by adjusting the shape or volume of the soundproof space (320S), the frequency of sound waves to be absorbed by the filter air guide (300) can be determined.

[0263] It may be desirable for the filter air guide (300) to absorb sound waves corresponding to a frequency range that has a certain range rather than absorbing sound waves corresponding to only one frequency. This is because the sound generated from the fan (100) or motor may have various frequencies.

[0264] Below, the principle of sound absorption by the soundproof space (320S) is described in detail in the part referring to Fig. 7 or Fig. 8.

[0265] According to the above explanation, the sound-absorbing hole (310H) and the sound-insulating space (320S) can reduce the sound volume.

[0266] When the air guide (AG) has a single resonant frequency, the frequency of sound that the air guide (AG) can absorb is sound having a single frequency. In order for the air guide (AG) to absorb sounds of various frequencies, the air guide (AG) may have various resonant frequencies. For this purpose, the filter air guide (300) may include a sound insulation unit (AU). There may be multiple sound insulation units (AU).

[0267] At this time, it is preferable that the frequency of the sound wave absorbed by the filter air guide (300) is within the audible frequency. The audible frequency is comprised of 20,000 Hz or less at the widest range, and is best heard by humans in the range of 500 Hz to 4000 Hz. Therefore, it is preferable that the frequency of the sound absorbed by the filter air guide (300) includes a frequency between 500 Hz and 4000 Hz. Accordingly, it is preferable that the resonant frequency of the plurality of soundproofing units (AU) is between 500 Hz and 4000 Hz.

[0268] The plurality of sound insulation units (AU) may include a first sound insulation unit (AU') and a second sound insulation unit (AU'') having a different resonance frequency from the first sound insulation unit (AU').

[0269] Each of the multiple sound insulation units (AU) may have a corresponding sound insulation space (320S).

[0270] The soundproof space (320S) may include a first soundproof space (320S) and a second soundproof space (320S). The first soundproof space (320S) may be a space corresponding to the first soundproof unit (AU'). The second soundproof unit (AU'') may be a soundproof space (320S) corresponding to the second soundproof space (320S).

[0271] To form multiple soundproof units (AU), the filter air guide (300) may include a separating baffle (330).

[0272] The separation bulkhead (330) can extend from the guide portion (310) to the space forming portion (320). The separation bulkhead (330) can extend vertically or horizontally within the soundproof space (320S).

[0273] The separation bulkhead (330) can independently separate a plurality of soundproof spaces (320S).

[0274] There may be multiple separation bulkheads (330).

[0275] A plurality of separation partitions (330) may be arranged in a pattern. A plurality of separation partitions (330) may be arranged in a circumferential direction based on the center of the guide passage (310P). When a plurality of separation partitions (330) are arranged at regular intervals, if the shape of the filter air guide (300) is approximately a rectangular parallelepiped, the volume of the sound insulation space (320S) corresponding to the corner portion and the sound insulation space (320S) corresponding to the edge portion may be defined differently.

[0276] The plurality of separation bulkheads (330) may include a first separation bulkhead (330') and a second separation bulkhead (330'') spaced apart from the first separation bulkhead (330').

[0277] The soundproof space (320S) can be defined by a guide part (310) and a space forming part (320). A guide part (310) and a space forming part (320) corresponding to the first soundproof space (320S) and the second soundproof space (320S) can be provided, respectively.

[0278] The guide portion (310) may include a first guide portion (310') defining a first soundproof space (320S) and a second guide portion (310'') defining a second soundproof space (320S).

[0279] The space forming portion (320) may include a first space forming portion (320') defining a first soundproofing space (320S) and a second space forming portion (320'') defining a second soundproofing space (320S).

[0280] The first soundproof space (320S) may be surrounded by a first guide portion (310'), a first space forming portion (320'), and a separating partition wall (330). The second soundproof space (320S) may be surrounded by a second guide portion (310''), a second space forming portion (320''), and a separating partition wall (330).

[0281] The first sound insulation space (320S) and the second sound insulation space (320S) can be provided independently. The first sound insulation space (320S) can be positioned adjacent to the second sound insulation space (320S). When the first sound insulation space (320S) is positioned adjacent to the second sound insulation space (320S), a separation partition (330) can be positioned between the first sound insulation space (320S) and the second sound insulation space (320S). In this case, the first sound insulation space (320S) can be defined by being surrounded by the separation partition (330) positioned between it and the second sound insulation space (320S), another separation partition (330), the first guide portion (310'), and the first space forming portion (320').

[0282] The sound-absorbing hole (310H) may include a first sound-absorbing hole (310H') corresponding to the first sound-insulating space (320S) and a second sound-absorbing hole (310H') corresponding to the second sound-insulating space (320S). Since the first sound-insulating space (320S) is defined by the first guide part (310'), the first sound-absorbing hole (310H') may be a configuration included in the first guide part (310'). Since the second sound-insulating space (320S) is defined by the second guide part (310''), the second sound-absorbing hole (310H') may be a configuration included in the second guide part (310'').

[0283] The first sound-absorbing hole (310H') may have a different diameter from the second sound-absorbing hole (310H'') so that the first sound-insulating unit (AU') has a different resonance frequency from the second sound-insulating unit (AU''). This is described in more detail in the description with reference to FIG. 22.

[0284] The volume of the first sound-absorbing hole (310H') may be different from the volume of the second sound-absorbing hole (310H'') so that the first sound-insulating unit (AU') has a different resonance frequency from the second sound-insulating unit (AU'').

[0285] There may be multiple sound-absorbing holes (310H). Accordingly, there may also be multiple first sound-absorbing holes (310H') or second sound-absorbing holes (310H'').

[0286] The number of the first sound-absorbing holes (310H') may be greater than the number of the second sound-absorbing holes (310H') so that the first sound-insulating unit (AU') has a different resonance frequency than the second sound-insulating unit (AU''). In other words, the number of the first sound-absorbing holes (310H') per volume of the first sound-insulating space (320S) may be different from the number of the second sound-insulating holes per volume of the second sound-insulating space (320S) so that the resonance frequency of the first sound-insulating unit (AU') is different from the resonance frequency of the second sound-insulating unit (AU''). This will be described in more detail in the description with reference to FIG. 21.

[0287] The sound-absorbing hole (310H) may have a predetermined diameter. Since the filter air guide (300) not only reduces the volume of sound, but also reduces sound within an environment where air flows by the fan (100), it is necessary to prevent sound from being generated by the air flow. To this end, the diameter of the sound-absorbing hole (310H) may be limited. A detailed description thereof will be provided with reference to FIGS. 14 to 17.

[0288] The sound-absorbing holes (310H) may vertically penetrate the guide portion (310) to prevent the distance between two points on the opening from exceeding a predetermined value. The predetermined value may be 2.0 mm. However, for process reasons, some of the sound-absorbing holes (310H) may vertically penetrate the guide portion (310), but some of the sound-absorbing holes (310H) may penetrate the guide portion (310) in a direction intersecting the direction perpendicular to the guide portion (310). In other words, at least some of the sound-absorbing holes (310H) may vertically penetrate the guide portion (310).

[0289] The above description assumes and describes application to the filter air guide (300). However, the present invention is not limited thereto, and the same principle may be applied to the fan air guide (300-1). In other words, the above description may be applied to the air guide (AG).

[0290] Fig. 7 is an enlarged cross-sectional view showing the filter air guide (300) shown in Fig. 5 cut and enlarged. Fig. 8 is a conceptual diagram conceptually illustrating the principle of sound absorption shown in Fig. 7.

[0291] Referring to FIGS. 7 and 8, a principle of reducing the sound level of one embodiment of the present disclosure is explained.

[0292] Referring to FIGS. 7 and 8, the noise reduction effect by the filter air guide (300) according to one embodiment of the present disclosure is described.

[0293] As shown in Fig. 8, a pipe can be assumed in which one end is closed and the other end is open.

[0294] Assume that sound (W1) is transmitted through a tube. Since sound is a vibration of air, it can have a wavelength and a frequency.

[0295] In order for sound (W1) to be absorbed in a tube, the end of the sound (W1) wave needs to be located in the closed part of the tube. If the end of the sound wave (W1) wave is located in the closed part of the tube, the sound wave (W1) has difficulty propagating in the direction of propagation because there is no medium provided in the closed part of the tube. Furthermore, this phenomenon occurs when the beginning of a wave is located in the open part of the tube. In other words, this phenomenon occurs when the nodes of the wave are located in the open part and the closed part of the tube.

[0296] That is, when the length of the wavelength matches the length of the tube, the wavelength of that length is absorbed by the tube. The energy of the sound wave (W1) can be converted into heat energy as it is absorbed by the tube.

[0297] If a sound wave has a specific wavelength, and since the speed of sound in air is constant, that sound wave can be said to have a specific frequency. Therefore, a pipe can be said to absorb sound waves of a specific frequency depending on its length. This can be expressed as the pipe absorbing sound waves of that frequency when the resonant frequency of the pipe matches the frequency of the sound wave.

[0298] However, if the wavelength of the sound wave (W1) is too long, the length of the tube required to absorb the sound wave (W1) may be too long. This may mean that the product size may become too large to design the tube length required to absorb the sound (W1). Therefore, the tube length needs to be reduced.

[0299] Let us assume that there is a sound wave (W2) with a wavelength that is twice the wavelength of the sound wave (W1) mentioned as an example.

[0300] The nodes of the corresponding sound wave (W2) can be located in the open and closed portions of the tube, respectively. Inside the tube, a portion corresponding to a half wavelength of the sound wave (W2) can be located. Even in such a case, the sound wave (W2) can be absorbed by the tube, as in the case where one wavelength is located inside the tube.

[0301] Furthermore, suppose there is a sound wave (W3) with a wavelength that is again twice the wavelength of the sound wave (W2).

[0302] When the node of the sound wave (W3) is located in the closed part of the tube and the valley or peak of the sound wave (W3) is located in the open part of the tube, the sound wave (W3) can be absorbed in the tube, as if one wave were located inside the tube.

[0303] As in the last example, even if a tube is made with a length equivalent to one-quarter of the sound wave's wavelength, the sound wave can still be absorbed by the tube. Therefore, the length of the tube required to absorb sound can be reduced.

[0304] As explained above, sound waves can only be absorbed by a tube if one of the wave's troughs, crests, or nodes is located in an open portion of the tube. Therefore, it is desirable to have multiple tubes so that the wavelengths of the sound waves generated by sound generation are located in the open portion of the tube.

[0305] As illustrated in Fig. 7, there may be a plurality of sound-absorbing holes (310H). This may be to increase the number of sound waves absorbed through the sound-absorbing holes (310H).

[0306] A plurality of sound-absorbing holes (310H) may be uniformly distributed on the air guide (AG), as illustrated in FIG. 4. This may be to ensure that sound waves are smoothly absorbed regardless of where they are located on the air guide (AG).

[0307] As illustrated in Fig. 7, the soundproof space (320S) may have a configuration corresponding to the pipe described above.

[0308] Sound waves passing through the sound-absorbing hole (310H) move to the sound-insulating space (320S) and can be absorbed by a portion of the air guide (AG) having a frequency corresponding to the frequency of the sound waves.

[0309] At this time, the sound wave to be absorbed may be affected by the diameter of the sound-absorbing hole (310H), the thickness of the guide part (310), the depth of the sound-absorbing hole (310H), and the porosity (the ratio of the total area of ​​the sound-absorbing hole (310H) to the area of ​​the guide part (310)). The smaller the diameter of the sound-absorbing hole (310H), the larger the thickness of the guide part, the deeper the depth of the sound-absorbing hole (310H), and the smaller the porosity, the more difficult it is for the sound wave to escape through the sound-absorbing hole (310H) in the soundproof space (320S), and thus the sound can be said to be better absorbed. On the other hand, the smaller the diameter of the sound-absorbing hole (310H), the larger the thickness of the guide part, the deeper the depth of the sound-absorbing hole (310H), and the smaller the porosity, the more sound waves with longer wavelengths and lower frequencies can be absorbed.

[0310] This principle can be seen to apply to all embodiments described in this disclosure and to all cases to which the ideas of this disclosure are applied.

[0311] The multiple acoustic isolation units (AUs) discussed above can be designed to have different resonant frequencies. To achieve these different resonant frequencies, the variables described above can be adjusted to design each unit to have a different frequency.

[0312] Furthermore, according to the above principle, an excessively large soundproof space (320S) may be required to absorb sound waves of the required frequency.

[0313] For example, a sound wave of 1000 Hz, which is in the audible range of the audible frequency range, may have a length corresponding to 1 / 4 wavelength of 85 mm. In order to implement a soundproof space (320S) of 85 mm in length within the air cleaner (AL), the air cleaner (AL) may be larger than necessary.

[0314] However, in the case of a noise reduction device composed of a sound-absorbing hole (310H) and a sound-insulating space (320S), as in the embodiment of the present disclosure, sound waves of a desired frequency can be absorbed with a width of only 1 / 10 of the wavelength.

[0315] A noise reduction device comprising a sound-absorbing hole (310H) and a sound-insulating space (320S) may produce a negative value when calculating the air density value in the area adjacent to the sound-absorbing hole (310H). A structure that produces results that deviate from common physical knowledge can be referred to as a meta-structure. The air guide (AG) may have a meta-structure.

[0316] An air guide (AG), which is a meta-structure having a sound-absorbing hole (310H) and a sound-insulating space (320S), can form an air guide (AG) having a resonant frequency corresponding to a frequency of 1000 Hz even if it does not have a length of 85 mm. In other words, the air guide (AG) can have a sound-insulating space (320S) with a length of 1 / 10 of the corresponding wavelength in order to reduce sound in the low-frequency range.

[0317] Additionally, the explanation above, focusing on sounds with a frequency band of 1000 Hz, can be similarly applied to the ranges above 1000 Hz and below 1000 Hz. In other words, to prevent users from experiencing discomfort due to noise, it is necessary to reduce sounds across all frequency bands. Accordingly, the concepts regarding the sound-absorbing hole (310H) and sound-insulating space (320S) applied above can be used to reduce sounds corresponding to any frequency.

[0318] Noise reduction devices must not only reduce noise near the noise source, but also effectively reduce noise in an air-flowing environment. This is explained below.

[0319] Fig. 9 is a cross-sectional view illustrating air flowing through the filter air guide (300) illustrated in Fig. 5. Fig. 10 is a graph illustrating the noise reduction effect by the filter air guide (300) illustrated in Fig. 9.

[0320] Referring to FIGS. 9 and 10, the effect of an air guide (AG) according to one embodiment of the present disclosure is described.

[0321] As illustrated in Fig. 9, the air guide (AG) provided with a plurality of sound-absorbing holes (310H) corresponding to the soundproof unit (AU) can be referred to as a microporous panel-type noise reduction device. In other words, the filter air guide (300) can be referred to as a microporous panel-type noise reduction device. Furthermore, the fan air guide (300-1) with reference to Fig. 14 can also be referred to as a microporous panel-type noise reduction device.

[0322] As shown in Fig. 9, a filter air guide (300) was installed in an air purifier (AL), and the fan (100) was operated to test how much the sound level was reduced.

[0323] In the experiment, the air velocity was configured to be 1 m / s immediately after passing through the filter (200), 10 m / s at the fan inlet (100Aa), and 15 m / s at the fan outlet (100Ab). The experimental results are as shown in Fig. 10.

[0324] The X-axis of the graph shown in Figure 10 represents frequency, and the Y-axis represents sound pressure level. The X-axis represents 500 Hz per unit, and the Y-axis represents 10 dB per unit.

[0325] Comparing before and after installing the filter air guide (300), it can be seen that the graph after shows a sound reduction effect of approximately 3 dB. In other words, the filter air guide (300) can have a noise reduction effect.

[0326] Figure 11 is an enlarged cross-sectional view of the part illustrated in Figure 9.

[0327] Referring to FIG. 11, the shape of the flow induction path (311P) of the filter air guide (300) according to one embodiment of the present disclosure is described.

[0328] As shown in Fig. 9, the diameter of the opening located in front of the guide path (310P) of the filter air guide (300) can be referred to as S2, and the diameter of the opening located in the rear can be referred to as S1.

[0329] And, the smallest diameter in the cross section within the guide euro (310P) can be referred to as Smin. Smin can have a length greater than 90% of S1 or S2.

[0330] The part from which Smin is defined to the point where S2 is defined can be referred to as a flow induction part (320). The filter air guide (300) can include the flow induction part (320). The flow induction part (320) can define a flow induction path (311P).

[0331] The flow induction path (311P) may be configured to have a cross-sectional area that increases as it goes forward. The flow induction path (311P) may be configured to have a cross-sectional area that increases as it goes toward the fan inlet (100Aa).

[0332] The flow guide portion (320) may extend from the guide portion (310). The flow guide portion (320) may extend from the guide portion (310) toward the fan inlet (100Aa). The flow guide portion (320) may be inclined toward the fan inlet (100Aa) with respect to the guide portion (310).

[0333] For example, in the cross-sectional view as illustrated in Fig. 11, the end of the flow guide member (320) may extend upward. The flow guide path (311P) by the flow guide member (320) may function as a diffuser. If the guide path (310P) functions to gather air like a nozzle, the flow guide path (311P) may function to diffuse air like a diffuser.

[0334] The flow induction path (311P) may have a flow induction surface along which air flows. When the air flows along the flow induction surface, the shroud (120) of the fan (100) (see FIG. 3) may move along the direction in which it extends. The shroud (120) of the fan (100) may extend while being inclined in a direction away from the rotational axis of the fan (100) as it goes forward so as to facilitate the flow of air by the blades (110) (see FIG. 3).

[0335] Accordingly, the flow induction path (311P) can be inclined to allow air to move in the extension direction of the fan guide path (100P) formed by the shroud (120) of the fan (100).

[0336] In other words, the fan (100) may include a shroud (120) between the blade (110) and the air guide (AG), the shroud (120) extending radially from the center of rotation of the blade (110) along the axis of rotation of the blade (110). The air guide (AG) may have a flow induction path (311P) whose cross-sectional area gradually increases from the end of the guide path (310P) toward the shroud (120) so that air moves in the extension direction of the shroud (120) while the fan (100) is operating.

[0337] As mentioned above, the length of Smin is greater than 90% of the length of S1 or S2, thereby preventing turbulence when air is moved. Sudden changes in the flow path (10P) can cause turbulence in the flow. By ensuring that the length of Smin is a predetermined value, turbulence in the air can be prevented.

[0338] Preferably, when the length of S1 is 6.83 times the length in the front-back direction of the guide part (310), and the length of S2 is 15.80 times the length in the front-back direction of the flow induction part (320), and when the length of Smin is 0.99 times the length of S2, turbulence can be prevented.

[0339] In the case of including a filter air guide (300) having the above dimensions, it can be confirmed through experiments that there is no loss in the air velocity when the air velocity is tested to be 1 m / s immediately after passing through the filter (200), 10 m / s at the fan inlet (100Aa), and 15 m / s at the fan outlet (100Ab).

[0340] Fig. 12 is a perspective view illustrating the fan air guide (300-1) illustrated in Fig. 4. Fig. 13 is an enlarged cross-sectional perspective view illustrating the fan air guide (300-1) illustrated in Fig. 12 cut and enlarged.

[0341] Referring to FIGS. 12 and 13, the structure of a fan air guide (300-1) according to one embodiment of the present disclosure will be described.

[0342] The description regarding the filter air guide (300) can also be applied to the fan air guide (300-1). The fan air guide (300-1) will be described in detail below.

[0343] The fan air guide (300-1) can define a soundproof space (320S). The second air guide portion (310b) included in the fan air guide (300-1) can be expressed as a guide portion (310) included in the fan air guide (300-1). The second air guide path (310Pb) can be expressed as a guide path (310P) included in the fan air guide (300-1). The second air guide sound-absorbing hole (310Hb) can be expressed as a sound-absorbing hole (310H) included in the fan air guide (300-1). The second air guide sound-absorbing space (320Sb) can be expressed as a sound-absorbing space (320S) included in the fan air guide (300-1).

[0344] In particular, as illustrated in FIG. 14, the soundproof space (320S) may be defined by the housing (10). The soundproof space (320S) may be defined by the blower case (101) (see FIG. 3). When the housing (10) or the blower case (101) is adjacent to the fan air guide (300-1), the space formed between the housing and the fan air guide (300-1) may become the soundproof space (320S).

[0345] The housing (10) or blower case (101) can surround a soundproof space (320S) together with the guide portion (310) of the fan air guide (300-1).

[0346] The soundproof space (320S) may be in communication with the sound-absorbing hole (310H). Since the soundproof space (320S) may be adjacent to the guide portion (310), the soundproof space (320S) may be positioned adjacent to the sound-absorbing hole (310H). The soundproof space (320S) may be in communication with the outside of the fan air guide (300-1) through the sound-absorbing hole (310H).

[0347] The volume of the soundproof space (320S) may be larger than the volume of the sound-absorbing hole (310H).

[0348] The sound volume can be reduced by the sound-absorbing hole (310H) and the sound-insulating space (320S).

[0349] When sound waves enter the soundproof space (320S) through the sound-absorbing hole (310H), the volume of the soundproof space (320S) is large compared to the entrance diameter of the sound-absorbing hole (310H), so it may be difficult for the sound waves to escape from the soundproof space (320S) through the sound-absorbing hole (310H).

[0350] The smaller the diameter of the sound-absorbing hole (310H), the less sound may be emitted outside the air purifier (AL). This is because the sound-absorbing hole (310H) may be an outlet configured to allow sound waves to exit from the sound-insulating space (320S) to the outside of the sound-insulating space (320S).

[0351] The larger the volume of the soundproof space (320S), the better the sound waves can be received into the soundproof space (320S). Therefore, the volume of the soundproof space (320S) can determine the degree of sound absorption.

[0352] As mentioned above, the sound-absorbing hole (310H) can define the resonant frequency of the fan air guide (300-1). The sound-insulating space (320S) can also define the resonant frequency of the fan air guide (300-1). This is because the sound-insulating space (320S) is an empty space and can define the shape of the fan air guide (300-1).

[0353] That is, the soundproof space (320S) can determine the frequency of sound waves to be absorbed by the fan air guide (300-1). In other words, by adjusting the shape or volume of the soundproof space (320S), the frequency of sound waves to be absorbed by the fan air guide (300-1) can be determined.

[0354] It may be desirable for the fan air guide (300-1) to absorb sound waves corresponding to a frequency range that has a certain range rather than absorbing sound waves corresponding to only one frequency. This is because the sound generated from the fan (100) or motor may have various frequencies.

[0355] According to the above explanation, the sound-absorbing hole (310H) and the sound-insulating space (320S) can reduce the sound volume.

[0356] When the air guide (AG) has a single resonant frequency, the frequency of sound that the air guide (AG) can absorb is a sound having a single frequency. In order for the air guide (AG) to absorb sounds of various frequencies, the air guide (AG) may have various resonant frequencies. For this purpose, the fan air guide (300-1) may include a sound insulation unit (AU). There may be multiple sound insulation units (AU).

[0357] At this time, it is preferable that the frequency of the sound wave absorbed by the fan air guide (300-1) is within the audible frequency range. The audible frequency range is broadly comprised of 20,000 Hz or less, and humans can hear best in the range of 500 Hz to 4000 Hz. Therefore, it is preferable that the frequency of the sound absorbed by the fan air guide (300-1) includes a frequency between 500 Hz and 4000 Hz. Accordingly, it is preferable that the resonant frequency of the plurality of soundproofing units (AU) is between 500 Hz and 4000 Hz.

[0358] The plurality of sound insulation units (AU) may include a first sound insulation unit (AU') and a second sound insulation unit (AU'') having a different resonance frequency from the first sound insulation unit (AU'). However, although not illustrated in the drawing with respect to the separating partition (330) that divides the plurality of sound insulation spaces (320S), the fan air guide (300-1), which is an embodiment of the present disclosure, may also include the separating partition (330). Accordingly, the fan air guide (300-1) may define a first sound insulation space (320S) and a second sound insulation space (320S) defined by the separating partition (330). The guide portion (310) may include a first guide portion (310') that defines the first sound insulation space (320S) and a second guide portion (310'') that defines the second sound insulation space (320S). The sound-absorbing hole (310H) may include a first sound-absorbing hole (310H') corresponding to the first sound-blocking space (320S) and a second sound-absorbing hole (310H'') corresponding to the second sound-blocking space (320S). The sound-absorbing hole (310H) may be plural. Accordingly, the first sound-absorbing hole (310H') or the second sound-absorbing hole (310H'') may also be plural. The number of the first sound-absorbing holes (310H') may be greater than the number of the second sound-absorbing holes (310H'') so that the first sound-blocking unit (AU') has a different resonance frequency from the second sound-blocking unit (AU'').

[0359] The fan air guide (300-1) may include a guide inlet portion (313b). The guide inlet portion (313b) may be adjacent to the fan inlet (100Aa). The guide inlet portion (313b) may be an opening of the fan air guide (300-1). Air may move through the guide inlet portion (313b).

[0360] The guide inlet portion (313b) can extend forward from the guide portion (310).

[0361] The fan air guide (300-1) may include a diffuser portion (311b). The diffuser portion (311b) may extend forward from the guide inlet portion (313b). The diffuser portion (311b) may extend to correspond to the shroud (120).

[0362] The diffuser portion (311b) may form a circular opening. A cross-section cut along the axial direction of the diffuser portion (311b) may become larger as it moves forward.

[0363] The fan air guide (300-1) may include a guide portion (312b). The guide portion (312b) may extend forward from the diffuser portion (311b). The guide portion (312b) may form a circular opening. A cross-section taken along the axial direction of the guide portion (312b) may increase in size as it moves forward. However, a rate of change in the area of ​​the cross-section of the guide portion (312b) may be smaller than a rate of change in the area of ​​the cross-section of the diffuser portion (311b).

[0364] Fig. 14 is a cross-sectional view illustrating the fan air guide (300-1) illustrated in Fig. 12 together with a configuration for noise reduction. Fig. 15 is a graph illustrating a sound absorption effect when the fan air guide (300-1) illustrated in Fig. 14 has a sound absorption hole (310H) with a diameter of 0.5 mm. Fig. 16 is a graph illustrating a sound absorption effect when the fan air guide (300-1) illustrated in Fig. 14 has a sound absorption hole (310H) with a diameter of 1.0 mm. Fig. 17 is a graph illustrating a sound absorption effect when the fan air guide (300-1) illustrated in Fig. 14 has a sound absorption hole (310H) with a diameter of 2.0 mm.

[0365] Referring to FIGS. 14 to 17, the diameter of the sound-absorbing hole (310H) of a suitable fan air guide (300-1) according to one embodiment of the present disclosure is described.

[0366] The fan air guide (300-1) may surround the fan (100) to form a guide path (310P). In other words, the air guide (AG) may be spaced radially from the center of rotation of the fan (100) and extend in the circumferential direction, and a soundproof space (320S) may be between the air guide (AG) and the housing (10).

[0367] Figures 15 to 17 are graphs showing the noise reduction effect according to the change in diameter of the sound-absorbing hole (310H) of the fan air guide (300-1).

[0368] An experiment was conducted after installing a fan air guide (300-1) as illustrated in Fig. 14. In the experiment, the air flow rate was configured to be 1 m / s immediately after passing through the filter (200), 10 m / s at the fan inlet (100Aa), and 15 m / s at the fan outlet (100Ab). The X-axis of the illustrated graph represents frequency, and the Y-axis represents sound pressure level. The X-axis represents 500 Hz per unit, and the Y-axis represents 10 dB per unit.

[0369] As shown in Fig. 15, when the diameter (D) of the sound-absorbing hole (310H) is 0.5 mm, when the fan air guide (300-1) is installed, noise is reduced in the low-frequency range, and noise is also reduced in the high-frequency range, compared to when the fan air guide (300-1) is not installed.

[0370] As illustrated in Fig. 16, when the diameter (D) of the sound-absorbing hole (310H) is 1.0 mm, when the fan air guide (300-1) is installed, noise is reduced in the low-frequency range compared to when the fan air guide (300-1) is not installed, but noise is not reduced in the high-frequency range. There was no significant difference in noise in the high-frequency range between when the air guide (AG) was installed and when it was not installed.

[0371] As shown in Fig. 17, when the diameter (D) of the sound-absorbing hole (310H) is 2.0 mm, when the fan air guide (300-1) is installed, noise in the low-frequency range is not reduced compared to when the fan air guide (300-1) is not installed, and noise in the high-frequency range is rather increased.

[0372] This is because, although noise generated from the fan (100) or fan motor (130) is reduced by the sound-absorbing hole (310H) and the sound-insulating space (320S), sound may be generated due to the flow of air. When air flows, the air may also have a resonant frequency. At this time, resonance may occur when the resonant frequency of the fan air guide (300-1) and the resonant frequency of the flowing air match. When resonance occurs, the amplitude of the sound caused by it may increase.

[0373] That is, when air flows, a noise-reducing configuration must suppress sound generation caused by air flow in addition to simply reducing noise. To prevent air from resonating with the air guide (AG), the diameter of the sound-absorbing hole (310H) may be less than 2.0 mm. Preferably, the diameter of the sound-absorbing hole (310H) may be 0.5 mm or less.

[0374] In particular, the diameter of these sound-absorbing holes (310H) appeared to have a critical effect in the low-frequency range below 1000 Hz. The range below 1000 Hz is both within the human audible frequency range and also the frequency range in which humans can hear best.

[0375] Furthermore, by providing a sound-absorbing hole (310H) with a specific diameter, noise can be reduced even in a high-frequency range exceeding 1000 Hz. Accordingly, the sound-absorbing hole (310H) can reduce the volume of sound in both a low-frequency range below 1000 Hz and a high-frequency range exceeding 1000 Hz. By reducing sound in a certain frequency range, user discomfort due to noise can be reduced.

[0376] These experimental results can be equally applied to the filter air guide (300) as well as the fan air guide (300-1).

[0377] Fig. 18 is a cross-sectional view illustrating the filter air guide (300) and the fan air guide (300-1) illustrated in Fig. 4 together with a configuration for noise reduction. Fig. 19 is a graph illustrating the noise reduction effect of the filter air guide (300) and the fan air guide (300-1) illustrated in Fig. 18 at the front of the air purifier (AL). Fig. 20 is a graph illustrating the noise reduction effect of the filter air guide (300) and the fan air guide (300-1) illustrated in Fig. 18 at the rear of the air purifier (AL).

[0378] Referring to FIGS. 18 to 20, a noise reduction effect is described when a filter air guide (300) and a fan air guide (300-1) according to one embodiment of the present disclosure are included in an air purifier (AL).

[0379] As shown in Fig. 18, a filter air guide (300) and a fan air guide (300-1) were installed in an air purifier (AL), and an experiment was conducted to measure noise. In the experiment, the air flow rate was configured to be 1 m / s immediately after passing through the filter (200), 10 m / s at the fan inlet (100Aa), and 15 m / s at the fan outlet (100Ab). The X-axis (Frequency) of the graph shown represents frequency, and the Y-axis represents sound pressure level. The X-axis represents 500 Hz per unit, and the Y-axis represents 10 dB per unit.

[0380] As shown in Fig. 19, when the filter air guide (300) and the fan air guide (300-1) were installed, there was an average sound level reduction of 2.9 dB in front of the air purifier (AL).

[0381] As shown in Fig. 20, when the filter air guide (300) and the fan air guide (300-1) were installed, there was an average sound level reduction of 3.1 dB at the rear of the air purifier (AL).

[0382] In summary, noise reduction at the front and rear of the air purifier (AL) can be achieved by the filter air guide (300) and the fan air guide (300-1).

[0383] Above, an air purifier (AL) or noise reduction device according to one embodiment of the present disclosure has been described. Below, an air purifier (AL) or noise reduction device according to another embodiment of the present disclosure will be described. In describing other embodiments, components identical to those in the embodiments referred to in FIGS. 1 to 20 will be assigned the same drawing numbers, and descriptions thereof may be omitted.

[0384] FIG. 21 is a cross-sectional view of a filter air guide (300-2) of an air purifier (AL) according to one embodiment of the present disclosure.

[0385] Referring to FIG. 21, an air guide (AG) according to one embodiment of the present disclosure is described.

[0386] As illustrated in FIG. 21, the filter air guide (300-2) may include a plurality of first sound-absorbing holes (310H'-2) and a plurality of second sound-absorbing holes (310H''-2).

[0387] The density per area of ​​the unit guide portions (310) of the plurality of first sound-absorbing holes (310H'-2) may be different from the density per area of ​​the unit guide portions (310) of the plurality of second sound-absorbing holes (310H''-2). For example, as illustrated in FIG. 21, the plurality of first sound-absorbing holes (310H'-2) may be positioned lower than the plurality of second sound-absorbing holes (310H''-2) and may have a lower density. Accordingly, the filter air guide (300-2) may have a resonant frequency within a predetermined range.

[0388] The fan air guide (300-1) may also have a plurality of first absorption holes and a plurality of first sound absorption holes (310H'-2) and a plurality of second sound absorption holes (310H''-2) having different densities.

[0389] That is, the air guide (AG) may have a plurality of first absorption holes and a plurality of first sound-absorbing holes (310H'-2) and a plurality of second sound-absorbing holes (310H''-2) having different densities.

[0390] FIG. 22 is a cross-sectional view of a filter air guide (300-3) of an air purifier (AL) according to one embodiment of the present disclosure.

[0391] Referring to FIG. 22, an air guide (AG) according to one embodiment of the present disclosure is described.

[0392] As illustrated in FIG. 22, the filter air guide (300-3) may include a first sound-absorbing hole (310H'-3) and a second sound-absorbing hole (310H''-3).

[0393] The first sound-absorbing hole (310H'-3) may have a diameter different from that of the second sound-absorbing hole (310H''-3). For example, as illustrated in FIG. 22, the first sound-absorbing hole (310H'-3) may be positioned lower than the second sound-absorbing hole (310H''-3) and may have a smaller diameter. Accordingly, the filter air guide (300-3) may have a resonant frequency within a predetermined range.

[0394] The fan air guide (300-1) may also have a plurality of second absorption holes (310H''-3) having different diameters from the first absorption hole and the first sound absorption hole (310H'-3).

[0395] That is, the air guide (AG) may have a plurality of second absorbing holes (310H''-3) having different diameters from the first absorbing hole and the first absorbing hole (310H'-3).

[0396] Fig. 23 is an enlarged perspective view of a filter air guide (300-4) of an air purifier (AL) according to one embodiment of the present disclosure. Fig. 24 is a graph illustrating a noise reduction effect by the filter air guide (300-4) illustrated in Fig. 23.

[0397] Referring to FIGS. 23 and 24, an air guide (AG) according to one embodiment of the present disclosure is described.

[0398] As illustrated in Fig. 23, the filter air guide (300-4) may include a plurality of sound insulation units (AU). The plurality of sound insulation units (AU) may include a first sound insulation unit (AU'-4) and a second sound insulation unit (AU''-4).

[0399] The first sound insulation unit (AU'-4) may include a first sound-absorbing hole (310H'-4) and a first sound insulation space (320S).

[0400] The second soundproofing unit (AU''-4) may include a second sound-absorbing hole (310H''-4) and a second soundproofing space (320S).

[0401] In the filter air guide (300-4) according to the embodiment of the present disclosure, one sound-absorbing hole (310H) may correspond to one sound-insulating space (320S). In the filter air guide (300-4) according to the embodiment with reference to FIGS. 1 to 20, a plurality of sound-absorbing holes (310H) may correspond to one sound-insulating space (320S).

[0402] A structure like this can be called a Helmholtz resonance structure.

[0403] The filter air guide (300-4) may include a separation partition (330) to separate the first sound insulation unit (AU'-4) and the second sound insulation unit (AU''-4).

[0404] In order to make the resonance frequency of each sound insulation unit (AU) different, the size of each sound absorption hole (310H), the length of the sound absorption hole (310H), or the volume of the sound insulation space (320S) can be made different. That is, the volume of the first sound insulation space (320S'-4) and the volume of the second sound insulation space (320S''-4) can be made different. In order to make the volumes of the first sound insulation space (320S'-4) and the second sound insulation space (320S''-4) different, the first space forming part (320'-4) and the second space forming part (320''-4) can be different.

[0405] Furthermore, each acoustic unit (AU) may contain another Helmholtz resonance structure.

[0406] A Helmholtz resonance structure like this can also be applied to a fan air guide (300-1).

[0407] Accordingly, the air guide (AG) may have a sound-absorbing hole (310H) corresponding one-to-one to the sound-insulating space (320S) so as to have a Helmholtz resonance structure.

[0408] An experiment was conducted after installing a fan air guide (300-1) as illustrated in Fig. 23. In the experiment, the air flow rate was configured to be 1 m / s immediately after passing through the filter (200), 10 m / s at the fan inlet (100Aa), and 15 m / s at the fan outlet (100Ab). The X-axis of the illustrated graph represents frequency, and the Y-axis represents sound pressure level. The X-axis represents 500 Hz per unit, and the Y-axis represents 10 dB per unit.

[0409] As shown in Fig. 24, when the filter air guide (300-4) was installed, there was a noise reduction effect of up to 8 dB compared to when it was not installed.

[0410] Fig. 25 is an enlarged perspective view of a filter air guide (300-5) of an air purifier (AL) according to one embodiment of the present disclosure. Fig. 26 is a graph illustrating a noise reduction effect by the filter air guide (300-5) illustrated in Fig. 25.

[0411] Referring to FIGS. 25 and 26, an air guide (AG) according to one embodiment of the present disclosure is described.

[0412] As illustrated in Fig. 25, the filter air guide (300-5) may include a plurality of sound insulation units (AU). The plurality of sound insulation units (AU) may include a first sound insulation unit (AU') and a second sound insulation unit (AU'').

[0413] The first sound insulation unit (AU') may include a first sound-absorbing hole (310H') and a first sound insulation space (320S).

[0414] The second soundproofing unit (AU'') may include a second sound-absorbing hole (310H'') and a second soundproofing space (320S).

[0415] In the filter air guide (300-5) according to the embodiment of the present disclosure, one sound-absorbing hole (310H) may correspond to one sound-insulating space (320S). In the filter air guide (300-5) according to the embodiment with reference to FIGS. 1 to 20, a plurality of sound-absorbing holes (310H) may correspond to one sound-insulating space (320S).

[0416] However, the difference from the embodiment described with reference to FIGS. 22 and 23 is that the length of the soundproof space (320S) corresponds to 1 / 4 of the target wavelength. If the length of the soundproof space (320S) is 1 / 4 of the target wavelength, sound waves having the corresponding wavelength are absorbed, as described with reference to FIG. 8. In other words, the length of the soundproof space (320S) may be 1 / 4 of the sound wavelength generated when the fan (100) operates.

[0417] As previously discussed, extending the soundproof space (320S) by a length equal to 1 / 4 of the wavelength can increase the size of the air guide (AG). Therefore, the soundproof space (320S) can extend in one direction and then in the opposite direction. When viewed from the side, this structure can be described as "folding," meaning that it resembles a folding structure of the soundproof space (320S).

[0418] At this time, the soundproof space (320S) may be configured to have a constant width even along the extension direction. This is because if the width of the soundproof space (320S) varies along the extension direction, sound absorption may not occur properly.

[0419] The filter air guide (300-5) may include a separation partition (330) to separate the first sound insulation unit (AU') and the second sound insulation unit (AU'').

[0420] In order to make the resonance frequency of each sound insulation unit (AU) different, the size of each sound absorption hole (310H), the length of the sound absorption hole (310H), or the volume of the sound insulation space (320S) can be made different. That is, the volume of the first sound insulation space (320S'-5) and the volume of the second sound insulation space (320S''-5) can be made different. In order to make the volumes of the first sound insulation space (320S'-5) and the second sound insulation space (320S''-5) different, the first space forming part (320'-5) and the second space forming part (320''-5) can be different.

[0421] The air guide (AG) may include a separation partition (330) configured to divide a one-way extending portion of the soundproof space (320S) and a one-way extending portion opposite to the one-way extending portion.

[0422] Since the separation bulkhead (330) is configured to divide each soundproof space (320S), the length of the soundproof space (320S) extending from the sound-absorbing hole (310H) corresponding to each soundproof space (320S) may be different from the length to the wall surface. Accordingly, each soundproof space (320S) may have a different resonance frequency. Accordingly, the air guide (AG) may have a resonance frequency within a predetermined range. The air guide (AG) may absorb sound waves having a frequency within a predetermined range.

[0423] An experiment was conducted after installing a fan air guide (300-5) as illustrated in Fig. 26. In the experiment, the air flow rate was configured to be 1 m / s immediately after passing through the filter (200), 10 m / s at the fan inlet (100Aa), and 15 m / s at the fan outlet (100Ab). The X-axis of the illustrated graph represents frequency, and the Y-axis represents sound pressure level. The X-axis represents 500 Hz per unit, and the Y-axis represents 10 dB per unit.

[0424] As shown in Fig. 26, when the filter air guide (300-5) was installed, there was a noise reduction effect of up to 10 dB compared to when it was not installed.

[0425] The embodiments of the present disclosure described above can be expressed as follows.

[0426] An air purifier (AL) according to one embodiment of the present disclosure includes a housing (10) having a passage (10P) through which air can move, a fan (100) configured to allow air to move through the passage (10P) when operated, and an air guide (AG) adjacent to the fan (100), the air guide (AG) including a guide portion (310) having a guide surface (310A) configured to allow air to flow along while the fan (100) is operated, the guide portion (310) having a sound-absorbing hole (310H) configured to absorb sound generated when the fan (100) is operated, and the guide portion (310) can be configured to form a soundproof space (320S) communicating with the sound-absorbing hole (310H).

[0427] The volume of the sound-absorbing hole (310H) may be smaller than the volume of the sound-insulating space (320S) to prevent sound waves generated by the operation of the fan (100) from moving through the sound-absorbing hole (310H) in the sound-insulating space (320S).

[0428] The above air guide (AG) has a resonance frequency defined by the sound-absorbing hole (310H) and the sound-insulating space (320S), and the air guide (AG) can reduce the sound when the frequency of the sound generated while the fan (100) is in operation matches the resonance frequency of the air guide (AG).

[0429] The above air guide (AG) may further include a space forming portion (320) extending from the guide portion (310) configured to form the soundproof space (320S) between the guide portion (310).

[0430] The above air guide (AG) may include a partition wall extending from the space forming portion (320) toward the guide portion (310) to partition the soundproof space (320S) into a first soundproof space (320S) and a second soundproof space (320S) having a different volume from the first soundproof space (320S), a first soundproof unit (AU') defining the first soundproof space (320S), and a second soundproof unit (AU'') defining the second soundproof space (320S), wherein the second soundproof unit (AU'') has a resonance frequency different from a resonance frequency of the first soundproof unit (AU').

[0431] The above sound-absorbing hole (310H) includes a plurality of first sound-absorbing holes (310H) corresponding to the first sound-absorbing space (320S) and a plurality of second sound-absorbing holes (310H') corresponding to the second sound-absorbing space (320S), and the number of the plurality of first sound-absorbing holes (310H') per volume of the first sound-absorbing space (320S) may be different from the number of the plurality of second sound-absorbing holes per volume of the second sound-absorbing space (320S) so that the resonance frequency of the first sound-absorbing unit (AU') is different from the resonance frequency of the second sound-absorbing unit (AU').

[0432] The above sound-absorbing hole (310H) includes a first sound-absorbing hole (310H') corresponding to the first sound-blocking space (320S) and a second sound-absorbing hole (310H') corresponding to the second sound-blocking space (320S), and the diameter of the first sound-absorbing hole (310H') may be different from the diameter of the second sound-absorbing hole (310H') so that the resonance frequency of the first sound-blocking unit (AU') is different from the resonance frequency of the second sound-blocking unit (AU').

[0433] The diameter of the sound-absorbing hole (310H) may be less than 2.0 mm to prevent the generation of resonant sound caused by the air moving as the fan (100) operates.

[0434] The above sound-absorbing hole (310H) can penetrate the guide part (310) to prevent the distance between two points on the opening of the above sound-absorbing hole (310H) from becoming more than 2.0 mm.

[0435] The above air guide (AG) may have a meta structure in which the density of air adjacent to the sound-absorbing hole (310H) has a negative value while reducing sound in a frequency range of 1000 Hz or less among the frequencies of sound generated when the fan (100) operates.

[0436] The fan (100) has a fan inlet (100Aa) having a first cross-sectional area, and includes a filter (200) spaced apart from the fan (100) and having a second cross-sectional area larger than the first cross-sectional area, and the guide part (310) may include a guide path (310P) whose cross-sectional area decreases as it moves from the filter (200) toward the fan inlet (100Aa) to prevent the occurrence of turbulence when air passing through the filter (200) moves toward the fan inlet (100Aa) while the fan (100) is in operation.

[0437] The fan (100) includes a shroud (120) between the blade (110) and the air guide (AG), the shroud (120) extending radially from the center of rotation of the blade (110) toward the fan outlet (100Ab) along the rotation axis of the blade (110), and the air guide (AG) may further have a flow induction path (311P) whose cross-sectional area gradually increases from the end of the guide path (310P) toward the shroud (120) so that air moves in the extension direction of the shroud (120) while the fan (100) is operating.

[0438] In order for the above air guide (AG) to have a Helmholtz resonance structure, the sound-absorbing hole (310H) can correspond one-to-one with the sound-insulating space (320S).

[0439] The length by which the above soundproof space (320S) extends may be one-fourth of the sound wavelength generated when the fan (100) operates.

[0440] The above air guide (AG) is spaced radially from the center of rotation of the fan (100) and extends in the circumferential direction, and the soundproof space (320S) may be between the air guide (AG) and the housing (10).

[0441] An air purifier (AL) according to one embodiment of the present disclosure comprises a housing (10) having an inlet (11S) and an outlet (12S), a filter (200) within the housing (10), a fan (100) configured to move air from the filter (200) to the outlet (12S) of the housing (10), the fan (100) having a fan inlet (100Aa) through which air can pass and having a cross-sectional area smaller than that of the filter (200), and an air guide (AG) between the fan (100) and the filter (200), the air guide (AG) having a guide path (310P) whose cross-sectional area becomes smaller as it goes toward the fan (100), and the air guide (AG) is a sound-absorbing hole (310H) configured to absorb sound generated as the fan (100) is operated, the sound-absorbing hole communicating with a soundproof space (320S) You can have a hole (310H).

[0442] The volume of the sound-absorbing hole (310H) may be smaller than the volume of the sound-insulating space (320S) to prevent sound waves generated by the operation of the fan (100) from moving through the sound-absorbing hole (310H) in the sound-insulating space (320S).

[0443] The air guide (AG) further includes a space forming portion (320) to define the soundproofing space (320S) between the guide portion (310), and the air guide (AG) may include a partition wall extending from the space forming portion (320) toward the guide portion (310) to divide the soundproofing space (320S) into a first soundproofing space (320S) and a second soundproofing space (320S) having a different volume from the first soundproofing space (320S), a first soundproofing unit (AU') defining the first soundproofing space (320S), and a second soundproofing unit (AU'') defining the second soundproofing space (320S), wherein the second soundproofing unit (AU'') has a resonance frequency different from a resonance frequency of the first soundproofing unit (AU').

[0444] The above sound-absorbing hole (310H) includes a plurality of first sound-absorbing holes (310H) corresponding to the first sound-absorbing space (320S) and a plurality of second sound-absorbing holes (310H') corresponding to the second sound-absorbing space (320S), and the number of the plurality of first sound-absorbing holes (310H') per volume of the first sound-absorbing space (320S) may be different from the number of the plurality of second sound-absorbing holes per volume of the second sound-absorbing space (320S) so that the resonance frequency of the first sound-absorbing unit (AU') is different from the resonance frequency of the second sound-absorbing unit (AU').

[0445] A noise reduction device according to one embodiment of the present disclosure includes an air guide (AG) positionable adjacent to a fan (100), wherein the air guide (AG) may include a guide body (310, 320); a sound-insulating space (320S) positioned inside the guide body (310, 320), and a sound-absorbing hole (310H) that is open toward the fan (100) to absorb sound generated when the fan (100) or motor is operated, is communicated with the sound-insulating space (320S), and has a smaller volume than the sound-insulating space (320S).

[0446] Unless explicitly stated otherwise, the embodiments described above may be combined with other embodiments. Alternatively, combinations between embodiments may be considered possible, unless one embodiment is explicitly restricted from being combined with another embodiment. Combinations of one embodiment with another embodiment are deemed to be disclosed in this document.

[0447] The above illustrates and describes specific embodiments. However, the invention is not limited to the above-described embodiments, and those skilled in the art will readily appreciate that various modifications and implementations can be made without departing from the spirit and scope of the invention as set forth in the claims below.

Claims

1. A housing having a passage through which air can move; a fan configured to allow air to move through said passage by operating; and An air guide adjacent to the above fan is included; The above air guide, A guide surface configured to allow air moving along the above-mentioned path to flow while the above-mentioned fan is in operation; An air purifier comprising a sound-absorbing hole extending from the guide surface to absorb sound generated by the fan while the fan is operating.

2. In paragraph 1, The above air guide, A guide part including the above guide surface and the above sound-absorbing hole; and Including a space forming part defining a soundproof space between the above guide part; The above guide surface is provided on one side of the guide part opposite to the other side facing the soundproof space, An air purifier in which the above sound-absorbing hole extends from the above guide surface through the above guide part to the above sound-insulating space.

3. In paragraph 2, An air purifier in which the volume of the sound-absorbing hole is smaller than the volume of the sound-blocking space so as to prevent sound waves generated by the operation of the fan from moving through the sound-absorbing hole in the sound-blocking space.

4. In paragraph 2, An air purifier in which the air guide has a resonant frequency defined by the sound-absorbing hole and the sound-insulating space, and the air guide reduces the generated sound when the frequency of the generated sound matches the resonant frequency of the air guide.

5. In paragraph 2, The above air guide divides the soundproof space into a first soundproof space and a second soundproof space having a different volume from the first soundproof space, and includes a partition wall extending from the space forming portion toward the guide portion; A first sound insulation unit defining the first sound insulation space and having a resonant frequency; and An air purifier comprising a second sound insulation unit defining the second sound insulation space, the second sound insulation unit having a resonance frequency different from the resonance frequency of the first sound insulation unit.

6. In paragraph 5, The above sound-absorbing hole is one of a plurality of first sound-absorbing holes and a plurality of second sound-absorbing holes, The above plurality of first sound-absorbing holes correspond to the first sound-insulating space, The above plurality of second sound-absorbing holes correspond to the second sound-insulating space, An air purifier in which the number of sound-absorbing holes of the plurality of first sound-absorbing holes per volume of the first sound-absorbing space is different from the number of sound-absorbing holes of the plurality of second sound-absorbing holes per volume of the second sound-absorbing space so that a resonant frequency of the first sound-absorbing unit is different from a resonant frequency of the second sound-absorbing unit.

7. In paragraph 5, The above sound-absorbing hole is one of a plurality of sound-absorbing holes, and the plurality of sound-absorbing holes are A first sound-absorbing hole corresponding to the first sound-proof space; and Including a second sound-absorbing hole corresponding to the second sound-proof space, An air purifier wherein the diameter of the first sound-absorbing hole is different from the diameter of the second sound-absorbing hole so that the resonant frequency of the first sound-blocking unit is different from the resonant frequency of the second sound-blocking unit.

8. In paragraph 1, An air purifier wherein the diameter of the sound-absorbing hole is less than 2.0 mm to prevent the generation of sound resonating by air moving along the path as the fan operates.

9. In paragraph 1, An air purifier in which the above sound-absorbing hole penetrates the guide part to prevent the distance between two points on the opening of the above sound-absorbing hole from exceeding 2.0 mm.

10. In paragraph 1, An air purifier in which the air guide has a meta structure capable of reducing sound in a frequency range of 1000 Hz or less among the frequencies of sound generated when the fan operates, and in which the density of air adjacent to the sound-absorbing hole has a negative value.

11. In paragraph 1, The above fan has a fan inlet having a first cross-sectional area, A filter having a second cross-sectional area larger than the first cross-sectional area can be installed in the air purifier so as to be spaced apart from the fan, An air purifier wherein, when the filter is installed in the air purifier, the guide member includes a guide path whose cross-sectional area decreases as it moves from the filter toward the fan inlet to prevent the occurrence of turbulence when air passing through the filter moves toward the fan inlet while the fan is operating.

12. In paragraph 11, The above fan, Blade, Fan outlets, and A shroud between the blade and the air guide, comprising a shroud extending radially from the center of rotation of the blade toward the fan outlet along the axis of rotation of the blade; An air purifier in which the air guide includes a flow induction path whose cross-sectional area gradually increases from an end of the guide path toward the shroud so that air is moved in the extension direction of the shroud when the fan is operating.

13. In paragraph 2, An air purifier in which the sound-absorbing hole corresponds one-to-one with the soundproof space so that the air guide has a Helmholtz resonance structure.

14. In paragraph 2, An air purifier in which the length of the above-mentioned soundproof space is extended is one-fourth of the wavelength of the generated sound.

15. In paragraph 1, The above air guide is spaced radially with respect to the rotation center of the fan and extends circumferentially with respect to the rotation center of the fan, The above soundproof space is an air purifier between the air guide and the housing.

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