KR20250014435A - Air purifier - Google Patents

Abstract

According to one aspect of the present invention, there is provided a frame having an inlet for introducing external air and an outlet for discharging the air; a filter disposed inside the frame for filtering air; a fan unit providing a blowing force so that air is introduced into the frame through the inlet and air filtered by the filter is discharged through the outlet; an opening/closing unit movable with respect to the frame so as to be in a first open state that opens the outlet, a second open state that opens a portion of the outlet so that an open area of the outlet is formed smaller than when it is in the first open state, or a closed state that closes the outlet; a driving unit that provides a driving force for moving the opening/closing unit; And an air purifier can be provided, including a controller that controls the driving unit and the fan unit so that the opening/closing unit is placed in one of the first open state, the second open state, and the closed state, and the controller controls the fan unit so that the rotation speed of the fan unit is reduced when the driving unit is driven so that the opening/closing unit is placed in one of the first open state, the second open state, and the closed state.

Description

Air Purifier {AIR PURIFIER}

The present invention relates to an air purifier.

In general, an air purifier is a device that purifies polluted air and changes it into fresh air, and performs the function of removing dust and bacteria and removing odors by passing the intake air through an air purification filter. Such an air purifier includes a housing having an outlet formed on the front and top surfaces, a blower fan positioned inside the housing to suck in air, an air purification filter that purifies the air, and an opening/closing means for opening and closing the outlet.

In relation to such an opening and closing means, Korean Patent Publication No. 10-2018-0046070 entitled “Air Purifier” (Patent Document 1) of the present applicant discloses an air purifier including a housing having a first air outlet through which air is discharged, a blower fan for drawing outside air into the interior of the housing and causing it to flow to the first air outlet, and an opening and closing member that rotates with respect to the housing for opening and closing the first air outlet.

However, the air purifier of Patent Document 1 has a problem in that noise may be generated by air discharged from the first air outlet when the opening/closing member rotates to open/close the first air outlet. In other words, although the opening area of the first air outlet changes by the rotation of the opening/closing member of the air purifier of Patent Document 1, the blowing force of the blower remains the same regardless of whether the opening/closing member rotates, so there is a problem in that noise may be generated by air passing through the first air outlet.

Korean Patent Publication No. 10-2018-0046070 (published on May 8, 2018)

One embodiment of the present invention is to provide an air purifier capable of reducing noise when an opening/closing unit of the air purifier is moved.

According to one aspect of the present invention, there is provided a frame having an inlet for introducing external air and an outlet for discharging the air; a filter disposed inside the frame for filtering air; a fan unit providing a blowing force so that air is introduced into the frame through the inlet and air filtered by the filter is discharged through the outlet; an opening/closing unit movable with respect to the frame so as to be in a first open state that opens the outlet, a second open state that opens a portion of the outlet so that an open area of the outlet is formed smaller than when it is in the first open state, or a closed state that closes the outlet; a driving unit that provides a driving force for moving the opening/closing unit; And an air purifier can be provided, including a controller that controls the driving unit and the fan unit so that the opening/closing unit is placed in one of the first open state, the second open state, and the closed state, and the controller controls the fan unit so that the rotation speed of the fan unit is reduced when the driving unit is driven so that the opening/closing unit is placed in one of the first open state, the second open state, and the closed state.

In addition, the controller controls the driving unit based on a plurality of movement modes so that the opening/closing unit is placed in one of the first open state, the second open state, and the closed state, and the plurality of movement modes include an initial movement mode that controls the driving unit for an initial operation time from a time when movement of the opening/closing unit is initiated; and a main movement mode that controls the driving unit after the initial operation time has elapsed, and an air purifier can be provided in which the controller controls the driving unit so that the driving unit rotates at an initial rotation speed when in the initial movement mode, and controls the driving unit so that the driving unit rotates at a main rotation speed greater than the initial rotation speed when in the main movement mode.

In addition, an air purifier may be provided in which the controller controls the fan unit so that the rotation speed of the fan unit is reduced to a preset reduction speed when in the initial movement mode.

In addition, an air purifier may be provided in which the controller controls the fan unit so that the rotation speed of the fan unit maintains the reduction speed when in the main movement mode.

In addition, an air purifier may be provided that further includes a sensor unit including a single sensor that detects the opening/closing unit when placed in the first open state and the closed state.

In addition, the plurality of movement modes further include a confirmation movement mode for controlling the driving unit when the opening/closing unit is detected by the sensor unit, and the controller, when in the confirmation movement mode, stops the driving unit so that the movement of the opening/closing unit stops, and then, in the main movement mode, re-rotates the driving unit in the same direction as the direction in which the driving unit was rotated, thereby providing an air purifier.

In addition, an air purifier may be provided in which the controller controls the fan unit so that, when in the confirmation movement mode, the rotation speed of the fan unit increases and is restored to the rotation speed before the decrease.

In addition, an air purifier may be provided in which the frame further has an outlet formed therein for discharging air in a direction different from the outlet, and the opening/closing unit causes air to flow through the outlet when in the closed state, causes less air to flow through the outlet when in the second open state than when in the closed state, and closes the outlet when in the first open state.

In one embodiment of the present invention, when the driving unit is driven to move the opening/closing unit of the air purifier to open or close the exhaust port, the rotation speed of the fan unit is reduced so that the amount of air discharged from the exhaust port can be reduced, thereby reducing noise generated by the air discharged from the exhaust port.

In addition, when the drive unit is driven, the rotation speed of the fan unit can be reduced, so that the opening/closing unit can be prevented from vibrating due to air discharged from the exhaust port.

In addition, when starting the drive unit, since the drive unit can be driven at a low rotational speed, the rotor of the motor can be prevented from losing its position.

Figure 1 is a perspective view of an air purifier according to one embodiment of the present invention.
FIG. 2 is a cross-sectional view of the air purifier taken along line A-A' when the opening/closing unit of the air purifier of FIG. 1 is in the first open state.
Fig. 3 is a cross-sectional view showing the opening/closing unit of the air purifier of Fig. 1 in a second open state.
Fig. 4 is a cross-sectional view showing the opening/closing unit of the air purifier of Fig. 1 in a closed/open state.

Hereinafter, specific embodiments for implementing the technical idea of the present invention will be described in detail with reference to the drawings.

In addition, when explaining the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted.

Also, when it is said that a component is 'connected' or 'flows' with another component, it should be understood that it may be directly connected or flowing with that other component, but there may also be other components in between.

The terminology used in this specification is only used to describe specific embodiments and is not intended to be limiting of the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

In addition, it is to be noted in advance that the expressions such as top, bottom, side, etc. in this specification are explained based on the illustration in the drawing and may be expressed differently if the direction of the object is changed. For the same reason, some components in the attached drawing are exaggerated, omitted, or schematically illustrated, and the size of each component does not entirely reflect the actual size.

Additionally, terms that include ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by such terms. These terms are used only to distinguish one component from another.

The word "comprising" as used in the specification means specifying a particular characteristic, region, integer, step, operation, element, and/or component, but does not exclude the presence or addition of any other particular characteristic, region, integer, step, operation, element, component, and/or group.

Hereinafter, an air purifier (1) according to one embodiment of the present invention will be described with reference to the drawings.

Referring to FIGS. 1 and 2, an air purifier (1) according to one embodiment of the present invention can purify polluted air into clean air by filtering dust, odor particles, etc. of air drawn into the interior. The air purifier (1) can suck in outside air into the interior, and discharge clean air purified inside to the exterior. The air purifier (1) can include a frame (100), a fan unit (200), a filter (300), a sensor unit (400), a driving unit (500), an opening/closing unit (600), and a controller (700).

The frame (100) accommodates a fan unit (200), a filter (300), a sensor unit (400), a driving unit (500), and an opening/closing unit (600), and can form the exterior of the air purifier (1). In addition, the frame (100) can be formed with an inlet (110) for introducing external air, an outlet (120) for discharging air, and an outlet (130) for discharging air in a direction different from the outlet (120). In other words, the inlet (110) and the outlet (130) are formed on the front surface of the frame (100), and the outlet (120) can be formed on the upper surface of the frame (100), but is not limited thereto, and can be formed on another surface of the frame (100).

The fan unit (200) can provide blowing force so that air can be drawn into the inner space of the frame (100) through the inlet (110). By the blowing force of the fan unit (200), the outside air can be filtered by the filter (300) and then guided by the inner surface of the frame (100) to flow toward the outlet (120) or the discharge port (130). In addition, the fan unit (200) can be placed lower than the opening/closing unit (600).

The filter (300) can filter air flowing into the internal space of the frame (100). For example, the filter (300) can be a HEPA filter. This filter (300) can be placed between the inlet (110) and the fan unit (200).

Referring further to FIGS. 3 and 4, the sensor unit (400) can detect the opening/closing unit (600) when the opening/closing unit (600) is in the first open state and closed state, which will be described later. In addition, the sensor unit (400) does not detect the opening/closing unit (600) when the second open state is placed. The sensor unit (400) can include a sensor (410) and a plurality of magnetic bodies (420).

The sensor (410) may be placed only once inside the frame (100). In other words, the sensor (410) may be supported on the frame (100) so as to be placed between the discharge port (120) and the duct member (620) inside the frame (100). This sensor (410) may detect the opening/closing unit (600) by detecting any one of the plurality of magnetic bodies (420).

A plurality of magnetic bodies (420) may be arranged to be spaced apart from each other in the forward and backward direction on the opening/closing member (610). In other words, the plurality of magnetic bodies (420) may be moved together with the opening/closing member (610). One of the plurality of magnetic bodies (420) may be arranged on the rear side of the opening/closing member (610), and another of the plurality of magnetic bodies (420) may be arranged on the front side of the opening/closing member (610). One of the plurality of magnetic bodies (420) may be detected by the sensor (410) when the opening/closing unit (600) is placed in the first open state. In other words, one of the plurality of magnetic bodies (420) may be arranged to face the sensor (410) when the opening/closing member (610) is moved forward so that the opening/closing unit (600) is placed in the first open state. In addition, another one of the plurality of magnetic bodies (420) may be detected by the sensor (410) when the opening/closing unit (600) is placed in the closed state. In other words, another one of the plurality of magnetic bodies (420) may be arranged to face the sensor (410) when the opening/closing member (610) is moved rearward so that the opening/closing unit (600) is placed in the closed state. In addition, the plurality of magnetic bodies (420) may not be detected by the sensor (410) when the opening/closing unit (600) is placed in the second open state. In other words, the sensor (410) may be positioned between the plurality of magnetic bodies (420) when the opening/closing unit (600) is placed in the second open state.

The driving unit (500) can provide a driving force to move the opening/closing unit (600). The driving unit (500) can be rotated around a rotation axis extending in the left/right direction, and can be arranged between the opening/closing member (610) and the flow path member (620). By rotating, the driving unit (500) can move the opening/closing member (610) and the flow path member (620) in different directions. In other words, when the driving unit (500) is rotated in one direction (counterclockwise in FIG. 2), the opening/closing member (610) can be moved forward, and the flow path member (620) can be moved backward. In addition, when the driving unit (500) is rotated in the other direction (clockwise in FIG. 2), which is the opposite direction of one direction, the opening/closing member (610) can be moved backward, and the flow path member (620) can be moved forward. This driving unit (500) may include a motor (510) and a gear unit (520).

The motor (510) can provide a driving force to move the opening/closing unit (600). The motor (510) can be supported on the frame (100). For example, the motor (510) can be supported on the frame (100) so as to be placed between the urea member (620) and the opening/closing member (610).

The gear part (520) can be engaged with the opening/closing unit (600) and rotated around a rotation axis extending in the left/right direction by the driving force of the motor (510) to move the opening/closing unit (600). The gear part (520) can be engaged with the opening/closing member (610) and the flow path member (620) at the same time. In other words, the gear part (520) can be rotated between the opening/closing member (610) and the flow path member (620). When the gear part (520) is rotated, the flow path member (620) and the opening/closing member (610) can be moved in different directions.

The opening/closing unit (600) is movably arranged inside the frame (100) and can open/close at least one of the discharge port (120) and the outlet port (130) of the frame (100). In other words, the opening/closing unit (600) can be moved by the driving unit (500) and placed in any one of the first open state, the second open state, and the closed state.

The first open state is a state in which the opening/closing unit (600) opens the discharge port (120) and closes the discharge port (130). In other words, when the opening/closing unit (600) is in the first open state, filtered air is discharged from the discharge port (120) and cannot be discharged from the discharge port (130).

The second open state may be a state in which a part of the discharge port (120) is opened and the discharge port (130) is opened so that the open area of the discharge port (120) is formed smaller than when the opening/closing unit (600) is in the first open state. In other words, when the opening/closing unit (600) is in the closed state, air can flow through the discharge port (120) and the discharge port (130). When the opening/closing unit (600) is in the second open state, filtered air can be discharged from the discharge port (120) and the discharge port (130). The open area of the discharge port (120) may mean an uncovered area of the opening/closing member (610) described below when viewed in the vertical direction.

The closed state may be a state in which the opening/closing unit (600) closes the discharge port (120) and opens the discharge port (130). In other words, when the opening/closing unit (600) is in the closed state, filtered air can only be discharged from the discharge port (130). In addition, when in the closed state, the opening/closing unit (400) can allow more air to flow into the discharge port (130).

This opening/closing unit (600) may include an opening/closing member (610) and a flow member (620).

The opening/closing member (610) is movably supported on the frame (100) and can open/close the discharge port (120). In other words, the opening/closing member (610) can open the discharge port (120) when the opening/closing unit (600) is in the first open state, open a part of the discharge port (120) when the opening/closing unit (600) is in the second open state, and close the discharge port (120) when the opening/closing unit (600) is in the closed state. The opening/closing member (610) can be reciprocally moved forward and backward within the frame (100) by the driving unit (500). For example, the opening/closing member (610) can be arranged at the lower side of the discharge port (120) and moved forward to open the discharge port (120) or moved backward to close the discharge port (120). In addition, when the opening/closing member (610) opens the discharge port (120), the front side can be arranged in front of the front side of the discharge port (120). When the opening/closing unit (600) is moved to be placed in either the second open state or the closed state, the opening/closing member (610) can be moved rearward, thereby reducing the open area of the discharge port (120). In addition, when the opening/closing unit (600) is moved to be placed in the first open state or the second open state, the opening/closing member (610) can be moved forward, thereby increasing the open area of the discharge port (120).

The flow member (620) is movably supported on the frame (100) and can open and close the outlet (130). The flow member (620) can be moved in the opposite direction to the opening/closing member (610). In addition, the flow member (620) can be reciprocated in the forward and backward direction inside the frame (100) by the driving unit (500). The flow member (620) can provide a passage for guiding filtered air introduced into the inside toward the outlet (130). When the flow member (620) is moved forward, the rear end of the flow member (620) is spaced apart from the inside of the frame (100), so that the passage of the flow member (620) and the inside of the frame (100) can be communicated. In other words, when the opening/closing unit (600) is placed in either the second open state or the closed state, the flow path member (620) is spaced apart from the inside of the frame (100), so that the filtered air flowing inside the frame (100) can flow to the outlet (130) through the internal passage of the flow path member (620). In addition, when the flow path member (620) moves rearward, the rear end of the flow path member (620) can come into contact with the inside of the frame (100), so that the passage of the flow path member (620) and the inside of the frame (100) can be blocked. In other words, when the opening/closing unit (600) is placed in the first open state, the flow path member (620) moves rearward and comes into contact with the inside of the frame (100), the filtered air flowing inside the frame (100) can be blocked from flowing into the inside of the flow path member (620). In addition, the movement distance of the flow member (620) when the opening/closing unit (600) moves from the first open state to the closed state can be formed to be smaller than the movement distance of the opening/closing member (610). In other words, when the opening/closing unit (400) is in the first open state, the flow member (620) can block air from flowing into the inside by having its rear end contact the rear of the frame (100), thereby closing the discharge port (130). In addition, when the opening/closing unit (400) is in the second open state, the flow member (620) can have its rear end spaced apart from the rear of the frame (100) by a predetermined first distance, thereby allowing air to flow into the inside and out toward the discharge port (130). In addition, when the opening/closing unit (400) is in a closed state, the rear end of the vortex member (620) is spaced apart from the rear of the frame (100) by a second distance greater than the first distance, so that air drawn into the interior can flow toward the discharge port (130). The amount of air drawn into the vortex member (620) may be greater when the opening/closing unit (600) is in a closed state than when it is in the second open state.

The controller (700) can control the fan unit (200) and the driving unit (500). The controller (800) can control the driving unit (500) so that the opening/closing unit (600) is placed in one of the first open state, the second open state, and the closed state. When the controller (700) drives the driving unit (500) so that the opening/closing unit (600) is placed in one of the first open state, the second open state, and the closed state, the controller (700) can control the fan unit (200) so that the rotation speed of the fan unit (200) is reduced. In other words, when the driving unit (500) starts to rotate in a stopped state, the controller (700) can reduce the rotation speed of the fan unit (200) to a preset reduction speed.

The controller (700) can control the driving unit (500) based on a plurality of movement modes so that the opening/closing unit (600) is placed in one of the first open state, the second open state, and the closed state. The plurality of movement modes can further include an initial movement mode, a main movement mode, and a confirmation movement mode. In other words, the controller (700) can control the driving unit (500) and the fan unit (200) in the initial movement mode, the main movement mode, and the confirmation movement mode so as to move the opening/closing unit (600) to one of the first open state, the second open state, and the closed state. The initial movement mode, the main movement mode, and the confirmation movement mode can be performed sequentially.

The initial movement mode is a mode for controlling the drive unit (500) during the initial operation time from the time when the movement of the opening/closing unit (600) is initiated. The controller (700) can control the drive unit (500) so that the drive unit (500) rotates at the initial rotation speed when in the initial movement mode. In other words, the controller (700) can move the opening/closing unit (600) so that the opening/closing unit (600) is placed in one of the first open state, the second open state, and the closed state by rotating the drive unit (500) at the initial rotation speed during the initial operation time. For example, the initial rotation speed can be the rotation speed when the motor rotates at 200 pps (pulse per second). In addition, the controller (700) can control the fan unit (200) so that the rotation speed of the fan unit (200) decreases at a decreasing speed when in the initial movement mode. When the rotation speed of the fan unit (200) is reduced in the initial movement mode, the air flowing into the interior of the frame (100) and the filtered air discharged to the exterior of the frame (100) through at least one of the exhaust port (120) and the discharge port (130) may also be reduced.

The main movement mode is a mode that controls the driving unit (500) after the initial operation time has elapsed. In other words, the main movement mode is a mode that is performed after the initial movement mode. The controller (700) can control the driving unit (500) to rotate at a main rotation speed greater than the initial rotation speed when in the main movement mode. For example, the large main rotation speed can be the rotation speed when the motor (430) rotates at 500 pps. In addition, the controller (700) can control the rotation speed of the fan unit (200) to maintain a decreasing speed when in the main movement mode.

The confirmation movement mode is a mode for controlling the driving unit (500) when the opening/closing unit (600) is detected by the sensor unit (600). In other words, the confirmation movement mode may be a mode that is performed when the opening/closing unit (600) is placed in the first open state or closed state to confirm whether the opening/closing unit (600) is correctly positioned in the first open state or closed state. The controller (700) may stop the driving unit (500) so that the movement of the opening/closing unit (600) is stopped when in the confirmation movement mode. In addition, the controller (700) may re-rotate the driving unit (500) in the same direction as the direction in which the driving unit (500) rotated in the main movement mode after stopping the driving unit (500) in the confirmation movement mode. For example, if the drive unit (500) was rotated in one direction in the main movement mode, the controller (700) can rotate the drive unit (500) in one direction again in the confirmation movement mode. In addition, if the drive unit (500) was rotated in the other direction, which is the opposite direction of the one direction, in the main movement mode, the controller (700) can rotate the drive unit (500) in the other direction again in the confirmation movement mode.

In addition, when the controller (700) is in the confirmation movement mode, if the driving unit (500) is stopped, the rotation speed of the fan unit (200) can be increased so that the rotation speed of the fan unit (200) is restored to the rotation speed before the decrease. In other words, the controller (700) can control the rotation speed of the fan unit (200) that was decreased in the initial movement mode to be formed to the rotation speed before the initial movement mode. Since the rotation of the fan unit (200) can be increased in this initial movement mode, the filtered air discharged to the outside through at least one of the exhaust port (120) and the discharge port (130) can be increased again.

Hereinafter, the operation and effect of an air purifier (1) according to one embodiment of the present invention will be described.

In an air purifier (1) according to one embodiment of the present invention, when the driving unit (500) is driven, the rotation speed of the fan unit (200) can be reduced, thereby preventing the opening/closing unit (400) from vibrating due to air discharged from the exhaust port (120).

In addition, when the opening/closing unit (400) of the air purifier (1) is moved to open or close the exhaust port (120), the rotation speed of the fan unit (200) is reduced, so that the amount of air discharged from the exhaust port (120) can be reduced, and thus noise generated by the air discharged from the exhaust port (120) can be reduced.

In addition, when starting the drive unit (500), since the drive unit (500) can be driven at a low rotational speed, the rotor of the motor (320) can be prevented from being disengaged. In other words, since the drive unit (500) can be rotated at the initial rotational speed, the motor can be driven stably in the initial movement section.

Although the embodiments of the present invention have been described as specific embodiments, these are merely examples, and the present invention is not limited thereto, but should be interpreted to have the widest scope according to the technical idea disclosed in this specification. Those skilled in the art may implement a pattern of a shape not specified by combining/substituting the disclosed embodiments, but this also does not go beyond the scope of the present invention. In addition, those skilled in the art may easily change or modify the disclosed embodiments based on this specification, and it is clear that such changes or modifications also fall within the scope of the rights of the present invention.

1: Air purifier
100: Frame 110: Inlet
120: outlet 130: outlet
200: Fan unit 300: Filter
400: Sensor unit 410: Sensor
420: Magnet 500: Drive Unit
510: Motor 520: Gear
600: Opening unit 610: Opening member
620: Euro Absence 700: Controller

Claims (8)

A frame having an inlet for introducing outside air and an outlet for discharging the air;
A filter arranged inside the frame to filter air;
A fan unit that provides blowing force so that air is drawn into the frame through the inlet and air filtered by the filter is discharged through the outlet;
An opening/closing unit movable with respect to the frame so as to be in a first open state that opens the outlet, a second open state that opens a portion of the outlet so that the open area of the outlet is formed smaller than when in the first open state, or a closed state that closes the outlet;
A driving unit that provides a driving force to move the above opening/closing unit; and
The above opening/closing unit includes a controller that controls the driving unit and the fan unit so that the above opening/closing unit is in one of the first open state, the second open state, and the closed state.
The above controller
When the driving unit is driven so that the opening/closing unit is placed in one of the first open state, the second open state, and the closed state, the fan unit is controlled so that the rotation speed of the fan unit is reduced.
Air purifier. In paragraph 1,
The above controller,
The driving unit is controlled based on a plurality of movement modes so that the opening/closing unit is placed in one of the first open state, the second open state, and the closed state,
The above multiple movement modes are:
An initial movement mode for controlling the driving unit during an initial operation time from the time when the movement of the opening/closing unit is initiated; and a main movement mode for controlling the driving unit after the initial operation time has elapsed.
The above controller,
When in the initial movement mode, the driving unit is controlled so that the driving unit rotates at the initial rotation speed, and when in the main movement mode, the driving unit is controlled so that the driving unit rotates at the main rotation speed greater than the initial rotation speed.
Air purifier. In the second paragraph,
The above controller,
When in the above initial movement mode, the fan unit is controlled so that the rotation speed of the fan unit is reduced to a preset reduction speed.
Air purifier. In the third paragraph,
The above controller,
When in the above main movement mode, the fan unit is controlled so that the rotation speed of the fan unit maintains the reduction speed.
Air purifier. In the second paragraph,
Further comprising a sensor unit including a single sensor that detects the opening/closing unit when placed in the first open state and the closed state.
Air purifier. In paragraph 5,
The above multiple movement modes are:
When the above opening/closing unit is detected by the above sensor unit, a confirmation movement mode for controlling the above driving unit is further included.
The above controller,
When in the above confirmation movement mode, the driving unit is stopped so that the movement of the opening/closing unit is stopped, and then the driving unit is re-rotated in the same direction as the direction in which the driving unit was rotated in the main movement mode.
Air purifier. In paragraph 6,
The above controller,
When in the above confirmation movement mode, the fan unit is controlled so that the rotation speed of the fan unit increases and is restored to the rotation speed before the decrease.
Air purifier. In paragraph 1,
In the above frame, an outlet is further formed to discharge air in a direction different from the outlet,
The above opening/closing unit, when in the closed state, allows air to flow through the discharge port, when in the second open state, allows less air to flow through the discharge port than when in the closed state, and closes the discharge port when in the first open state.
Air purifier.

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