JP7384638B2 - mobile air purifier - Google Patents

Description

The present invention relates to a mobile air cleaner.

As an example of an autonomous air purifier, paragraph [0007] of Patent Document 1 below states, "...In a self-propelled air purifier, an intake port is provided in the center of the upper surface of the housing, and Since the exhaust ports are provided on the outer edge of the top surface and on the side, the flow of clean air exhausted from the self-propelled air purifier includes a horizontal component.As a result, the middle space of the room, Air purification (replacement with clean air) in the so-called living space can be performed quickly. Also, since the first filter member and the second filter member are provided, the air can be purified even more reliably. Since the first filter member and the second filter member are rotated by the motor, it is possible to achieve both quietness and high dust collection performance.In addition, the fan, the first filter member, and the second filter member can be easily rotated. It is possible to integrate the air purifier into a self-propelled air purifier, thereby achieving miniaturization of the self-propelled air purifier.''
Further, as an example of a self-propelled vacuum cleaner, paragraphs [0011] and [0012] of Patent Document 2 state that "the support structure for the rotating shaft for an auxiliary brush of the present invention is capable of rotating the rotating shaft." At times, since the first sliding surface of the rotating shaft and the second sliding surface of the sliding bearing are configured to be able to press against each other in the axial direction of the rotating shaft and to be able to come into sliding contact in the rotational direction, the rotating shaft and the housing are ``As a result, according to the present invention, the auxiliary brush can reduce the wear of the rotating shaft of the side brush, the rotating shaft, and the bottom of the casing, and the occurrence of rattling caused by this. It is possible to provide a support structure for a rotating shaft and a self-propelled vacuum cleaner equipped with the same.

International Publication No. 2018/074052 Japanese Patent Application Publication No. 2018-47357

By the way, among the fine particles such as pollen and house dust that exist in a living space, there are some that remain suspended for a long time and others that accumulate on the floor surface in a relatively short time. There is also a concern that even if the particles have once accumulated on the floor, they may be lifted up again by human activities and be inhaled by people. Therefore, when attempting to clean these fine particles, it is considered preferable to collect both those floating in the air and those deposited on the floor surface. However, the self-propelled air cleaner described in Patent Document 1 has a low ability to collect particulates deposited on the floor surface. Furthermore, the self-propelled vacuum cleaner described in Patent Document 2 has a low ability to collect particulates floating in the air.
This invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a mobile air cleaner that can appropriately collect both particulates floating in the air and particulates deposited on the floor surface.
(Means for solving problems)
In order to solve the above-mentioned problems, the mobile air cleaner of the present invention includes a housing, a first tube provided inside the housing, formed in a cylindrical shape, and filtering air passing from the outer circumferential surface toward the inner circumferential surface. a filter, an impeller provided in the housing to allow air to pass through the first filter, and whose lower end suction port is installed at a lower position than the lower end surface of the first filter; a first motor provided in the casing and driving the impeller; a bottom plate provided at the bottom of the casing and having a main body suction port for sucking air; and a bottom plate attached to the casing. a plurality of wheels that separate the brush from the installation surface, and a brush protruding downward from the bottom plate so as to contact the installation surface, and the brush width, which is the width of the brush, is the center of the brush when viewed from the bottom. The distance from the central point to the farthest point in the area of the main body suction port is shorter than twice the outer diameter of the suction port.

According to the present invention, both fine particles floating in the air and fine particles deposited on the floor surface can be appropriately collected.

FIG. 1 is a perspective view of a mobile air cleaner according to a first preferred embodiment. It is another perspective view of a mobile air cleaner. FIG. 3 is a bottom view of the mobile air cleaner. 4 is a sectional view taken along line IV-IV in FIG. 3. FIG. FIG. 2 is an exploded perspective view of the mobile air cleaner. It is a figure which shows the numerical simulation result of the flow field in a mobile air cleaner. It is a figure which shows the numerical simulation result of another flow field in a mobile air cleaner. It is a figure showing the relationship between speed ratio and area ratio. FIG. 3 is a cross-sectional view of main parts of a mobile air cleaner according to a second preferred embodiment.

Embodiments of the present invention will be described in detail below with reference to the drawings as appropriate. The following description shows specific examples of the content of the present invention, and the present invention is not limited to these descriptions. Various changes and modifications can be made by those skilled in the art within the scope of the technical idea disclosed in this specification, and it is planned from the beginning that the following configurations will be combined as appropriate. Further, in all the figures for explaining the present invention, parts having the same functions are given the same reference numerals, and repeated explanation thereof may be omitted. Then, front and back, top and bottom, and left and right are defined as shown in FIG. 1 and the like.

[First embodiment]
<Configuration of first embodiment>
(overall structure)
FIG. 1 is a perspective view of a mobile air cleaner 1 according to a first preferred embodiment.
The mobile air cleaner 1 includes a main body 1H formed into a substantially rectangular parallelepiped, and a traveling mechanism 1r that causes the main body 1H to travel. The main body 1H includes an exterior cover 2 (casing) and a decorative board 2r. The exterior cover 2 is a housing formed into a substantially rectangular parallelepiped frame shape. Further, the decorative board 2r is formed in a substantially Π shape when viewed from the side, and covers the upper surface and the front and rear surfaces of the exterior cover 2. The decorative board 2r is slidable in the vertical direction with respect to the exterior cover 2.

FIG. 2 is a perspective view of the mobile air cleaner 1 in a state where the decorative board 2r is slid upward.
The upper surface of the exterior cover 2 is covered with an upper surface cover 2f formed in a substantially rectangular grid shape. Further, the center portion of the top cover 2f serves as a main body discharge port 2o for discharging air. Furthermore, a distance sensor 21 is provided on the front surface of the exterior cover 2 to measure the distance to an obstacle (not shown) in front.

FIG. 3 is a bottom view of the mobile air cleaner 1.
As shown in FIG. 3, the bottom surface of the main body 1H is covered with a substantially rectangular plate-shaped bottom cover 2t (bottom plate). A pair of left and right side wheels 9s1 and 9s2 (wheels) are exposed at the left and right ends of the exterior cover 2. These side wheels 9s1 and 9s2 are included in the traveling mechanism 1r. A plurality of main body suction ports 2i (suction ports) are formed in the bottom cover 2t. These main body suction ports 2i have a shape obtained by dividing a ring centered on the center point O along the radial direction. A lattice mesh coarse filter 4 (second filter) is attached to the bottom cover 2t so as to cover each main body suction port 2i. The coarse filter 4 is installed at a position substantially flush with the bottom cover 2t, and collects pieces of paper, hair, fiber dust, and the like.

The brush 10b is formed into a substantially rectangular plate shape, and the center portion of the brush 10b is rotatably supported in the horizontal direction at the center point O of the bottom cover 2t. When the brush 10b is rotationally driven, the brush 10b slides on the floor surface and winds up particulates deposited on the floor surface. Brush 10b is included in floor cleaning mechanism 1z. The width of the brush 10b is called a brush diameter Db (width). The brush 10b is rotationally driven in the direction of arrow β so that the tip speed becomes Vb. A rear wheel 9k is attached to the bottom cover 2t via casters 9c slightly behind the rotation range of the brush 10b. The casters 9c are rotatably supported by the bottom cover 2t. Here, the side wheels 9s1 and 9s2 become driving wheels, and the rear wheel 9k becomes a driven wheel. Further, the rear wheels 9k and casters 9c are also included in the traveling mechanism 1r.

Moreover, the distance from the center point O to the shortest point Pm in the opening area of the main body suction port 2i is called the suction port inner diameter Rm. Moreover, the distance from the center point O to the farthest point Pn in the opening area of the main body suction port 2i is called the suction port outer diameter Rn. It is preferable that the brush diameter Db be shorter than twice the suction port outer diameter Rn. This makes it easier to collect the dust kicked up by the brush 10b from the main body suction port 2i, thereby reducing the amount of dust scattered indoors. Furthermore, as in the illustrated example, it is more preferable that the brush diameter Db be shorter than twice the suction port inner diameter Rm. This is because it becomes easier to collect the dust kicked up by the brush 10b from the main body suction port 2i.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3.
As shown in FIG. 4, the mobile air cleaner 1 includes a blower mechanism 1w, a traveling mechanism 1r, a floor cleaning mechanism 1z, an exterior cover 2, a top cover 2f, a bottom cover 2t, and a decorative board 2r. , a fine filter 3 (first filter), a coarse filter 4 (second filter), a dust sensor 20, a distance sensor 21, a control unit 22, and a storage battery 23. Of these, the exterior cover 2, the top cover 2f, the bottom cover 2t, and the decorative board 2r function as a substantially rectangular parallelepiped housing that houses other components.

The fine filter 3 is formed in a substantially cylindrical shape and removes finer dust and the like than the coarse filter 4. More specifically, the dense filter 3 includes a HEPA filter that has a pleated nonwoven fabric and can capture up to 99.97% of particles of 0.3 μm, and a deodorizing filter for removing odor components. There is. The fine filter 3 is provided at the top of the main body 1H in the height direction, that is, directly below the top cover 2f. The upper part of the upper cover 2f inside the dense filter 3 serves as the main body outlet 2o.

When the mobile air cleaner 1 is not activated, the decorative plate 2r is closed (see FIG. 1), and the upper plate of the decorative plate 2r is positioned directly above the main body discharge port 2o. The brush 10b is provided so as to be in contact with the floor surface Y (installation surface), and the brush motor 10m (third motor) rotates the rotation axis M in the vertical direction (more specifically, the direction orthogonal to the floor surface Y). It is driven to rotate in the direction of the arrow β (see FIG. 3) with the center at , and the fine particles deposited on the floor surface Y are rolled up. The fine particles that have been rolled up are inhaled and collected through the main body suction port 2i.

The blower mechanism 1w includes a centrifugal impeller (impeller) 6, an impeller motor 6m (first motor), and a winged diffuser 7. The impeller motor 6m is arranged coaxially with the centrifugal impeller 6 and rotates the centrifugal impeller 6. When the impeller motor 6m rotationally drives the centrifugal impeller 6, air near the lower surface of the main body 1H is sucked into the main body suction port 2i from the entire circumference of the main body 1H along the paths shown by arrows α1 and α7. At this time, the coarse filter 4 collects relatively large debris such as pieces of paper, hair, and fiber dust. The air that has passed through the coarse filter 4 is guided from the centrifugal impeller 6 to the outer circumferential side of the fine filter 3 along arrow α4. Then, air flows from the outer circumferential side to the inner circumferential side of the dense filter 3, and the purified air with dust etc. removed is discharged upward from the main body outlet 2o as shown by arrow α2. .

The traveling mechanism 1r also includes a pair of left and right side wheels 9s1 and 9s2, a pair of pulleys 9a, wheel motors 9m1 and 9m2 (second motors), and a rear wheel 9k. Wheel motors 9m1 and 9m2 drive side wheels 9s1 and 9s2, respectively, via a pair of pulleys 9a and a toothed belt (not shown). The side wheels 9s1 and 9s2 and the rear wheel 9k protrude downward from the bottom cover 2t and are in contact with the floor surface Y. The side wheels 9s1 and 9s2 are driving wheels, and here, the side wheels 9s1 and 9s2 are driving wheels, and the rear wheel 9k is a driven wheel. Further, the rear wheels 9k and casters 9c are also included in the traveling mechanism 1r.

(control system)
Further, the main body 1H is provided with various sensors. That is, the main body 1H includes a dust sensor 20 that detects dust, an odor sensor (not shown) that detects odor, a distance sensor 21 (see FIG. 2) that measures the distance to an obstacle, and a sensor that detects an obstacle. and an infrared sensor (not shown). Electric power is supplied to the control unit 22 from a storage battery 23 . The control unit 22 controls the impeller motor 6m, the wheel motors 9m1 and 9m2, and the brush motor 10m based on information from various sensors. Thereby, the mobile air cleaner 1 cleans the air in the room while autonomously running.

That is, the control unit 22 sets the mobile air purifier 1 to one of three operating modes: "weak," "standard," and "strong," based on information from the dust sensor 20 and the like. select. As described above, by having a plurality of operation modes, the mobile air cleaner 1 can automatically select an operation mode suitable for the degree of dirtiness of the air or the floor surface. However, the operation mode may be specified manually by the user.

(Airflow details)
Next, details of the airflow in this embodiment will be described with reference to FIG. 4.
When the impeller motor 6m rotationally drives the centrifugal impeller 6, air near the lower surface of the main body 1H is sucked into the main body suction port 2i from the entire circumference of the main body 1H along the paths shown by arrows α1 and α7.
In the coarse filter 4, pieces of paper, hair, fiber dust, etc. are removed from the air flowing in from the main body suction port 2i. The air then reaches the suction port 6i of the centrifugal impeller 6 through the inside of the duct 12 that forms a mortar-shaped flow path along the path indicated by the arrow α4. Thus, the coarse filter 4 is located below and upstream of the centrifugal impeller 6.
The air that has reached the suction port 6i of the centrifugal impeller 6 has a path bent from upward to sideways along the arrow α5 inside the centrifugal impeller 6, and passes through a winged diffuser 7 provided on the outer periphery of the centrifugal impeller 6. reach. The air that has reached the winged diffuser 7 is decelerated and pressurized inside the winged diffuser 7, and then its path is bent from sideways to upward along arrow α6, and reaches the dense filter 3.

The air that has reached the dense filter 3 flows from the outer circumferential surface of the dense filter 3 toward the inner circumferential surface along the arrow α3. At this time, the air is purified by removing fine dust, odors, etc. in the dense filter 3. After the purified air passes through the dense filter 3, the path of the purified air is bent from sideways to upward, and is discharged from the main body outlet 2o along the arrow α2.

(Arrangement of dense filter 3 and centrifugal impeller 6)
As described above, in this embodiment, the dense filter 3 is provided above the blowing mechanism 1w, and after the air flowing in from the blowing mechanism 1w passes through the dense filter 3, it is bent upward along the arrow α3. , leading to the main body discharge port 2о. In other words, the fine filter 3 is provided downstream of the centrifugal impeller 6. Further, the lower end surface 3b of the dense filter 3 is located above the suction port 6i, which is the lower end surface of the centrifugal impeller 6, and is further located above the upper end surface 6t of the centrifugal impeller 6. There is. With this configuration, the air discharged from the centrifugal impeller 6 reaches the dense filter 3 after being sufficiently decelerated, so that energy loss can be reduced. Furthermore, this configuration allows the dense filter 3 to be provided on the upper part of the main body 1H, making it easy to replace the dense filter 3.

FIG. 5 is an exploded perspective view of the mobile air cleaner 1.
As described above, the decorative board 2r can be pulled up from the exterior cover 2 (see FIG. 2). In this state, as shown in FIG. 5, the decorative board 2r can be further rotated to the left and tilted. Below the dense filter 3, a lower holding plate 30 formed in a substantially disk shape is fixed to the main body 1H.

Further, a substantially truncated conical protrusion 32 that protrudes upward is formed at the center of the lower holding plate 30, and furthermore, at the top of the protrusion 32, a cylindrical portion 34 with a female screw threaded on the inner periphery is formed. is formed. Above the fine filter 3, an upper holding plate 40 formed in a substantially disk shape is arranged. A cylindrical portion 42 is formed in the center of the upper restraining plate 40, protruding downward and having a male screw threaded on the circumferential surface. Further, approximately fan-shaped ventilation holes 44 are formed around the cylindrical portion 42 at four positions equally divided around the circumference.

In the above configuration, when the dense filter 3 is attached to the main body 1H, the dense filter 3 is placed on the lower holding plate 30, the cylindrical part 34 and the cylindrical part 42 are screwed together, and the upper holding plate 40 is manually held. It is best to rotate it. As a result, the fine filter 3 is pressed and held by the lower holding plate 30 and the upper holding plate 40. Next, the upper surface cover 2f is placed over the main body 1H above the upper holding plate 40, and the decorative plate 2r is rotated so as to be oriented vertically to return to the state shown in FIG. 2. Next, when the decorative board 2r is moved downward, the mobile air cleaner 1 returns to the state shown in FIG. 1.

Conversely, when removing the dense filter 3, lift the decorative plate 2r (see Figure 2), rotate the decorative plate 2r to the left and tilt it (see Figure 5), remove the top cover 2f, and remove the upper holding plate. 40 to separate the lower holding plate 30 and the upper holding plate 40, and then pull out the fine filter 3 upward. In this way, according to this embodiment, the dense filter 3 can be attached and detached manually by the user without using any tools or the like. Therefore, when the fine filter 3 becomes clogged, the user can easily replace the fine filter 3.

(About the center of gravity of the main body)
As shown in FIGS. 4 and 5, in this embodiment, the fine filter 3 is arranged at the upper part of the main body 1H. The dense filter 3 is mostly made of pleated nonwoven fabric in order to reduce ventilation resistance, and although it occupies a large volume, it is a relatively lightweight component compared to other components. By providing the dense filter 3, which occupies a large volume and is lightweight, in the upper part of the main body 1H, the dense filter 3 including the wheel motors 9m1, 9m2, the brush motor 10m, the control unit 22, the storage battery 23, etc. is provided below the main body 1H. It is possible to provide components that are relatively heavier than the above, and the center of gravity of the main body 1H can be lowered to a lower position. In this way, by lowering the center of gravity of the main body 1H, it is possible to suppress the shaking of the main body 1H due to inertia when the mobile air purifier 1 starts or stops, and the mobile air purifier 1 It is possible to realize stable and quiet running.

(Collection of suspended particles)
Next, the collection of particles suspended in the air will be explained.
In FIG. 4, the main body suction port 2i is open facing the floor surface Y, but since the bottom cover 2t is separated from the floor surface Y by a distance L, the main body suction port 2i is opened from the periphery of the exterior cover 2 along the arrow α7. It can inhale air and collect particles suspended in the air. Further, by providing the main body suction port 2i apart from the floor surface Y, pressure loss in the flow from around the exterior cover 2 to the main body suction port 2i can be reduced. As a result, the amount of air sucked by the main body 1H increases, and the indoor air can be quickly purified. Note that the distance L between the main body suction port 2i and the floor surface Y is, for example, 20 mm. Further, in the space below the exterior cover 2, a band-shaped region having a width of a distance L along the bottom edge of the exterior cover 2 is referred to as a bottom boundary D (see FIG. 6).

(Collection of deposited fine particles)
Next, the collection of fine particles deposited on the floor surface Y will be explained.
In FIG. 4, the brush 10b is rotationally driven by a brush motor 10m in the direction of arrow β (see FIG. 3) in FIG. Roll up. The fine particles rolled up by the brush 10b are taken into the main body 1H along with the air along the arrow α1 in FIG. 4 and cleaned.

6 and 7 are numerical simulation results showing the flow field at the VI-VI cross section in FIG. 4. In these figures, the direction of the arrow corresponds to the direction of the air flow, and the length of the arrow corresponds to the wind speed.
FIG. 6 shows an example in which the flow direction is radially inward around the entire circumference of the bottom boundary D. On the other hand, FIG. 7 shows a case where the flow direction is radially outward in a part R of the bottom boundary D. Here, the product of "bottom surface boundary length Dm (length of bottom surface boundary D)" and "separation distance L between main body suction port 2i and floor surface Y" is called bottom surface boundary area A. That is, the bottom surface boundary area A is expressed by the following equation (1).
A = Dm×L...Formula (1)
In equation (1), the unit of the bottom boundary area A is, for example, [m ² ], and the unit of the bottom boundary length Dm and the separation distance L is, for example, [m].

6 and 7, the volume of air flowing below the exterior cover 2 from the bottom boundary D, in other words, the volume of air blown by the centrifugal impeller 6 is referred to as the volume Q of air. When the air volume Q is relatively large and the tip speed Vb of the brush 10b (FIG. 3) is relatively low, air flows from the outside to the bottom boundary D over the entire circumference of the bottom boundary D, as shown in FIG. flows inside. On the other hand, when the air volume Q is relatively small and the tip speed Vb of the brush 10b is relatively high, as shown in FIG. R occurs. In the state shown in FIG. 7, there is a concern that the fine particles rolled up by the brush 10b will be scattered into the air.

FIG. 8 is a diagram showing the relationship between the speed ratio Va/Vb and the area ratio A ₁ /A.
In FIG. 8, the horizontal axis is the speed ratio Va/Vb between the speed Va and the tip speed Vb. Here, the speed Va and the tip speed Vb are values shown by the following equations (2) and (3), respectively. The unit of the air volume Q is, for example, [m ³ /min ⁻¹ ], the unit of the brush diameter Db is, for example, [m], and the unit of the brush rotation speed Nd is, for example, [min ⁻¹ ].
Va = Q/(60×A)...Formula (2)
Vb = Db×π×Nd/60…Formula (3)

Further, the vertical axis in FIG. 8 is the area ratio A ₁ /A between the area A 1 of _the two regions R where a radially outward flow occurs at the bottom boundary D and the bottom boundary area A.
As shown in FIG. 8, as the value of the speed ratio Va/Vb decreases, the value of the area ratio A ₁ /A increases, and the amount of fine particles scattered into the air increases. Here, the speed ratio Va/Vb is preferably set to 0.1 or more. The reason is that, as shown in the figure, when the speed ratio Va/Vb is set to 0.1 or more, the area ratio A ₁ /A can be suppressed to less than 0.01, and the fine particles rolled up by the brush 10b are released into the air. This is because scattering can be sufficiently suppressed.

Note that the numerical simulation results shown in FIGS. 6 and 7 show cases where the speed ratio Va/Vb is 0.28 and 0.02, respectively.
As an example of specific parameters in the standard mode of this embodiment, Dm = 1.12 [m], L = 0.02 [m], Db = 0.13 [m], Nd = 1000 [min ^-1 ] , Q=1.0 [m ³ /min ⁻¹ ], the speed ratio Va/Vb can be set to 0.11.

<Effects of the first embodiment>
As described above, the mobile air cleaner (1) of this embodiment allows air to pass through the first filter (3) provided in the housing (2), and also has a suction port (6i) at the lower end thereof. The impeller (6) is installed at a lower position than the lower end surface (3b) of the first filter (3), and the first impeller (6) is installed in the housing (2) and drives the impeller (6). A motor (6m), a bottom plate (2t) that is provided at the bottom of the housing (2) and has a main body suction port (2i) that sucks air, and a bottom plate (2t) that is attached to the housing (2). It includes a plurality of wheels (9s1, 9s2) that separate the brush from the installation surface (Y), and a brush (10b) that protrudes downward from the bottom plate (2t) so as to come into contact with the installation surface (Y). Thereby, according to this embodiment, both fine particles floating in the air and fine particles deposited on the floor surface can be appropriately collected. In addition, by installing the suction port (6i) at the lower end of the impeller (6) at a lower position than the lower end surface (3b) of the first filter (3), the first filter (3) can be easily removed. will be able to be exchanged.

In addition, the brush width (Db), which is the width of the brush (10b), is determined from the center point (O) of the brush (10b) in bottom view to the farthest point from the center point (O) in the area of the suction port (2i). (Pn) is preferably shorter than twice the suction port outer diameter (Rn), and the brush width (Db) is from the center point (O) of the brush (10b) in bottom view to the suction port (2i ) is more preferably shorter than twice the suction port inner diameter (Rm), which is the distance from the center point (O) to the shortest point (Pm). This makes it easier to collect dust kicked up by the brush (10b) from the suction port (2i).
Moreover, it is preferable that the mobile air cleaner (1) further includes a second motor (9m1, 9m2) that drives a plurality of wheels (9s1, 9s2). Thereby, the mobile air cleaner (1) can be automatically run.

It is preferable that the brush (10b) rotates while sliding on the installation surface (Y). Thereby, the brush (10b) can be slid on the installation surface (Y) at a faster speed than the moving speed of the mobile air cleaner (1).

Moreover, it is preferable that the mobile air cleaner (1) further includes a third motor (10m) that rotates the brush (10b). Thereby, the brush (10b) can be slid on the installation surface (Y) at a faster speed than the moving speed of the mobile air cleaner (1).

Further, it is preferable that the rotation axis (M) of the brush (10b) is perpendicular to the installation surface (Y). Thereby, the brush (10b) can be slid over a wide range of the installation surface (Y).

In addition, the length of the bottom outer circumference of the housing (2) is the bottom boundary length Dm, the distance between the main body suction port (2i) and the installation surface (Y) is the separation distance L, and Dm×L is the bottom boundary area A. , the amount of air blown by the impeller (6) is the air volume Q, Q/(60×A) is the speed Va, the width of the brush is Db, the rotation speed of the brush (10b) is the brush rotation speed Nd, Db×π When ×Nd/60 is the tip speed Vb of the brush (10b), Va/Vb is more preferably larger than 0.1. Thereby, the amount of fine particles scattered into the air can be effectively suppressed.

Moreover, it is preferable that the mobile air cleaner (1) includes a second filter (4) that is provided below and upstream of the impeller (6) and filters the air passing therethrough. This allows dust and the like to be removed from the air before it reaches the first filter (3).

[Second embodiment]
FIG. 9 is a sectional view of essential parts of a mobile air cleaner 1C according to a second embodiment of the present invention. In the following description, parts corresponding to those in the first embodiment described above may be denoted by the same reference numerals, and the description thereof may be omitted.
In the first embodiment described above, the coarse filter 4 was attached to the main body suction port 2i at the lower end of the duct 12 (see FIG. 4). On the other hand, in this embodiment, as shown in FIG. 9, a lattice-like coarse filter 4C is installed at the upper end of the duct 12, in other words, directly below the suction port 6i of the centrifugal impeller 6. Note that it is preferable that the coarse filter 4C be inserted and removed from either side of the exterior cover 2 (see FIG. 2). This facilitates cleaning and cleaning of the coarse filter 4C.

The configuration of this embodiment other than those described above is the same as that of the first embodiment (FIGS. 1 to 8). Note that the coarse filters such as the coarse filters 4 and 4C are not limited to those provided at the lower end of the duct 12 as in the first embodiment, or those provided at the upper end of the duct 12 as in the present embodiment. That is, the coarse filter can be provided at any location within the duct 12 from the lower end to the upper end, in other words, at any location below and upstream of the centrifugal impeller 6. No matter where the coarse filter is provided in the duct 12, it is possible to prevent the rotation of the centrifugal impeller 6 from being obstructed by clogging with dust.

[Modified example]
The present invention is not limited to the embodiments described above, and various modifications are possible. Possible modifications to the above embodiment include, for example, the following.
(1) In each of the above embodiments, the brush 10b (see FIG. 4) was rotationally driven by the brush motor 10m. However, the brush 10b does not necessarily need to be rotated. That is, even if the brush 10b is fixed to the bottom cover 2t, when the mobile air cleaners 1, 1C move, the brush 10b slides on the floor surface Y, so that the particulates accumulated on the floor surface Y are rolled up. Can be done.

(2) In each of the embodiments described above, a brush motor 10m that rotationally drives the brush 10b and an impeller motor 6m that rotationally drives the centrifugal impeller 6 are provided. However, one common motor (for example, the impeller motor 6m) may rotate the brush 10b and the centrifugal impeller 6. Thereby, the number of motors can be reduced and the cost of the mobile air cleaners 1 and 1C can be reduced.

(3) In each of the above embodiments, the dense filter 3 is formed into a substantially cylindrical shape, but by connecting filter plates (not shown) formed in a rectangular plate shape or a curved plate shape in an annular manner, the dense filter 3 may be formed.

(4) In each of the above embodiments, the brush 10b has a substantially rectangular plate shape, but the brush 10b may have a cross shape or an * shape, for example.

1 Mobile air purifier 2 Exterior cover (casing)
2i Main unit suction port 2t Bottom cover (bottom plate)
3 Dense filter (first filter)
3b Lower end surface 4 Rough filter (second filter)
6 Centrifugal impeller (impeller)
6i Suction port 6m Impeller motor (first motor)
9m1, 9m2 Wheel motor (second motor)
9s1, 9s2 Side wheels (wheels)
10b Brush 10m Brush motor (third motor)
M Rotation axis O Center point Y Floor surface (installation surface)
Db Brush diameter (brush width, width)
Pm Shortest point Pn Farthest point Rm Suction port inner diameter Rn Suction port outer diameter

Claims (9)

A casing and
a first filter that is provided within the housing and is formed in a cylindrical shape and filters air passing from the outer circumferential surface toward the inner circumferential surface;
an impeller that is provided in the housing and allows air to pass through the first filter, and the suction port at the lower end of the impeller is installed at a lower position than the lower end surface of the first filter;
a first motor provided within the housing and driving the impeller;
a bottom plate provided at the bottom of the housing and formed with a main body suction port for sucking air;
a plurality of wheels attached to the housing to separate the bottom plate from the installation surface;
a brush protruding downward from the bottom plate so as to come into contact with the installation surface ;
The brush width, which is the width of the brush, is shorter than twice the outer diameter of the suction port, which is the distance from the center point of the brush in a bottom view to the farthest point from the center point in the area of the main body suction port.
A mobile air purifier characterized by: The brush width, which is the width of the brush, is shorter than twice the inner diameter of the suction port, which is the distance from the center point of the brush in a bottom view to the shortest point from the center point in the area of the main body suction port. The mobile air cleaner according to claim 1 . The mobile air cleaner according to claim 1, further comprising a second motor that drives the plurality of wheels. The mobile air cleaner according to claim 1, wherein the brush rotates while sliding on the installation surface. The mobile air cleaner according to claim 4 , further comprising a third motor that rotates the brush. The mobile air cleaner according to claim 4 , wherein the axis of rotation of the brush is perpendicular to the installation surface. A casing and
a first filter that is provided within the housing and is formed in a cylindrical shape and filters air passing from the outer circumferential surface toward the inner circumferential surface;
an impeller that is provided in the housing and allows air to pass through the first filter, and the suction port at the lower end of the impeller is installed at a lower position than the lower end surface of the first filter;
a first motor provided within the housing and driving the impeller;
a bottom plate provided at the bottom of the housing and formed with a main body suction port for sucking air;
a plurality of wheels attached to the housing to separate the bottom plate from the installation surface;
a brush protruding downward from the bottom plate so as to come into contact with the installation surface;
The brush rotates while sliding on the installation surface,
A mobile air cleaner, wherein the first motor rotates the brush together with the impeller. A casing and
a first filter that is provided within the housing and is formed in a cylindrical shape and filters air passing from the outer circumferential surface toward the inner circumferential surface;
an impeller that is provided in the housing and allows air to pass through the first filter, and the suction port at the lower end of the impeller is installed at a lower position than the lower end surface of the first filter;
a first motor provided within the housing and driving the impeller;
a bottom plate provided at the bottom of the housing and formed with a main body suction port for sucking air;
a plurality of wheels attached to the housing to separate the bottom plate from the installation surface;
a brush protruding downward from the bottom plate so as to come into contact with the installation surface;
The brush rotates while sliding on the installation surface,
The length of the outer circumference of the bottom of the housing is the bottom boundary length Dm, the distance between the main body suction port and the installation surface is the separation distance L, Dm×L is the bottom boundary area A, and the amount of air blown by the impeller is The air volume is Q, Q/(60×A) is the speed Va, the width of the brush is Db, the rotation speed of the brush is the brush rotation speed Nd, and Db×π×Nd/60 is the tip speed of the brush Vb. A mobile air purifier characterized in that Va/Vb is greater than 0.1. The mobile air cleaner according to claim 1, further comprising a second filter that is provided below and upstream of the impeller and filters passing air.

Images