Air purifier

Abstract

An air purifier (1) is mounted to a mounting surface in a room and purifies the air in the room. The air purifier (1) comprises: a non-conductive housing (10) provided with a suction port (13) for sucking in air and an outlet port for blowing out air; a blower (70) that is accommodated in the housing (10) and generates an air flow for sucking in air from the suction port (13) and blowing out air from the outlet port; and a filter that is accommodated in the housing (10) and removes impurities in the air flow. The filter is grounded.

Description

air purifier

[0001] The present disclosure relates to an air purifier intended to purify indoor air.

[0002] Conventionally, there have been air purifiers that are mounted on walls to remove impurities such as dust from indoor air. However, when an air purifier is mounted on a wall, when dust approaches the wall on which the air purifier is mounted due to the flow of air circulating in the room, the dust is attracted to the wall by static electricity, and the dust adheres to the wall, causing the wall to become dirty.

[0003] As a countermeasure against the above-mentioned contamination of the wall surface, for example, Patent Document 1 describes a clean air blowing structure of an air purifier that blows clean air evenly around the periphery of the frame of the air purifier to prevent dust-containing air from approaching the wall surface.

[0004] Japanese Patent Application Publication No. 11-108404

[0005] However, according to the clean air blowing structure of the air purifier described in Patent Document 1, clean air is blown out from all around the air purifier, which places significant restrictions on where the air purifier can be placed on the wall surface of a room, and depending on the arrangement or structure of the parts housed inside the air purifier, problems such as reduced air volume and increased noise may arise.

[0006] The present disclosure has been made in consideration of the above, and aims to provide an air purifier that can prevent contamination of the installation surface caused by static electricity on the components, regardless of the airflow direction.

[0007] To solve the above-mentioned problems and achieve the object, the air purifier according to the present disclosure is an air purifier that is installed on an indoor installation surface and purifies the air in the room. The air purifier includes a non-conductive housing provided with an air inlet for drawing in air and an air outlet for blowing out air, a blower housed in the housing and generating an airflow that draws in air through the air inlet and blows out the air through the air outlet, and a filter housed in the housing and removing impurities from the airflow, the filter being grounded.

[0008] The air purifier according to the present disclosure has the advantage of being able to prevent contamination of the installation surface caused by static electricity on the components, regardless of the air blowing direction.

[0009] 2 is a diagram showing the appearance of the air purifier according to embodiment 1, which is a perspective view of the air purifier as viewed from above; FIG. 3 is a diagram showing the appearance of the air purifier according to embodiment 1, which is a perspective view of the air purifier as viewed from below; FIG. 4 is a diagram showing the appearance of a mounting plate attached to a wall surface on which the air purifier according to embodiment 1 is to be mounted; FIG. 5 is a configuration diagram showing an outline of the configuration of the air purifier according to embodiment 1, which is a diagram corresponding to a cross section taken along line V-V in FIG. 2; FIG. 6 is a configuration diagram showing an outline of the configuration of the air purifier according to embodiment 1, which is a diagram corresponding to a cross section taken along line VI-VI in FIG. 2; a perspective view showing the air purifier in a state in which the orifice has been removed from the state shown in FIG. 8; a diagram showing the appearance of a mesh filter provided in the air purifier according to the first embodiment; a diagram showing the appearance of an electric dust collector provided in the air purifier according to the first embodiment; a schematic diagram explaining the principle of electric dust collection in the electric dust collector provided in the air purifier according to the first embodiment; a diagram showing the appearance of a high-performance dust collecting filter provided in the air purifier according to the first embodiment; an enlarged view showing the periphery of a protrusion of a static eliminator plate of the air purifier according to the first embodiment; an enlarged view showing the rear metal plate connected to earth in the air purifier according to the first embodiment; a diagram showing an electrical connection path from the high-performance dust collecting filter to the ground in the air purifier according to the first embodiment;

[0010] Hereinafter, an air purifier according to an embodiment will be described in detail with reference to the drawings. Note that in the drawings shown below, the scale of each component may differ from the actual scale for ease of understanding. The same applies to each of the drawings.

[0011] Embodiment 1 (Overall configuration of air purifier 1) Fig. 1 is a diagram showing the appearance of air purifier 1 according to embodiment 1, and is a perspective view of air purifier 1 as viewed from above. Fig. 2 is a diagram showing the appearance of air purifier 1 according to embodiment 1, and is a perspective view of air purifier 1 as viewed from below. Fig. 3 is a diagram showing the appearance of air purifier 1 according to embodiment 1, and is a perspective view of air purifier 1 as viewed from above the rear side.

[0012] Air purifier 1 is an air purifier that is installed on a wall surface 200 and removes contaminants from indoor air to purify the indoor air environment. Wall surface 200 is the installation surface on which air purifier 1 is installed. Air purifier 1 has a housing 10 that forms the outer shell of air purifier 1. Housing 10 is configured from a housing main body 11 and a front panel 12 and has a rectangular parallelepiped shape. Housing 10 is made of a non-conductive resin and is therefore non-conductive.

[0013] The width direction of the air purifier 1 corresponds to the width direction of the housing 10 and corresponds to the X-axis direction in FIGS. 1 to 3 . The width direction of the air purifier 1 can be said to be the left-right direction. The depth direction of the air purifier 1 corresponds to the depth direction of the housing 10 and corresponds to the Y-axis direction in FIGS. 1 to 3 . The depth direction of the air purifier 1 can be said to be the thickness direction of the air purifier 1 or the thickness direction of the housing 10. The height direction of the air purifier 1 corresponds to the height direction of the housing 10 and corresponds to the Z-axis direction in FIGS. 1 to 3 . When the air purifier 1 is installed on a wall surface 200, the height direction of the air purifier 1 is the up-down direction, a direction parallel to the vertical direction. Furthermore, in the air purifier 1, the side where the front panel 12 is located in the depth direction is the front side, and the side opposite the side where the front panel 12 is located in the depth direction is the rear side. The left-right direction is the left-right direction when the air purifier 1 is viewed from the front side.

[0014] The housing main body 11 is a first component constituting the housing 10 and has a rectangular parallelepiped shape with one open side. As shown in FIGS. 1 to 3 , the housing 10 has a top surface 10a, a bottom surface 10b, a first side surface 10c, a second side surface 10d, a front surface 10e, and a back surface 10f. The first side surface 10c is the right side surface when viewed from the front side. The second side surface 10d is the left side surface when viewed from the front side. The first side surface 10c and the second side surface 10d are a pair of side surfaces facing each other in the width direction of the housing 10. The front surface 10e is formed by a front panel 12. One surface on the front side of the housing main body 11, i.e., the surface on the side of the housing 10 corresponding to the front surface 10e, is open. In addition, the top surface 10a, bottom surface 10b, first side surface 10c, second side surface 10d and back surface 10f can also be considered as the top surface of the housing body 11, the bottom surface of the housing body 11, the first side surface of the housing body 11, the second side surface of the housing body 11 and the back surface of the housing body 11, respectively.

[0015] The air purifier 1 is installed on the wall surface 200 with the back surface 10f facing the wall surface 200. Specifically, the air purifier 1 is installed on the wall surface 200 with the upper surface 10a facing vertically upward, the lower surface 10b facing vertically downward, the front surface 10e and the back surface 10f being parallel to the vertical direction, and the back surface 10f facing the wall surface 200. Therefore, when the air purifier 1 is installed on the wall surface 200, the back surface 10f facing the front panel 12 of the housing 10 is the facing surface facing the wall surface 200.

[0016] The housing 10 has an intake port 13, which is an opening for drawing indoor air into the housing 10, formed on the first side surface 10c. That is, the housing main body 11 has the intake port 13 formed on the first surface of the housing main body 11, which is the side surface adjacent to the open surface on the right side. The housing 10 also has an outlet port 14, which is an opening for blowing air inside the housing 10 to the outside of the housing 10, formed on the top surface 10a. That is, the housing main body 11 has the outlet port 14 formed on the second surface of the housing main body 11, which is the side surface adjacent to the open surface on the upper side, and the outlet port 14 is formed to open vertically upward when the housing is installed on the wall surface 200.

[0017] The front panel 12 is a lid that covers one open side of the housing body 11, and is the second component that constitutes the housing 10. In other words, the front surface of the air purifier 1 and the front surface 10e of the housing 10 are formed by the front panel 12. By removing the front panel 12 to the front side of the air purifier 1, the components housed inside the housing 10 can be accessed, allowing for periodic cleaning of the components housed inside the housing 10 and maintenance in the event of a malfunction.

[0018] The air purifier 1 is mounted on the wall surface 200 using a metal rear sheet metal hook 20 attached to the back surface 10f. Specifically, as shown in Fig. 3, the housing body 11 of the housing 10 has a rear sheet metal 22, which is a metal plate on which the rear sheet metal hook 20 used to mount the housing 10 on the wall surface 200 is formed, attached to the back surface 10f.

[0019] The rear metal sheet 22 is a metal mounting part used to mount the housing 10 on the wall surface 200. The rear metal sheet 22 is made of metal to ensure the strength required to mount the housing 10 on the wall surface 200 and hold the housing 10 in place. Here, since metal is disposed on the outer shell on the rear side of the housing 10, an earth connection for the air purifier 1 is required. As shown in FIG. 3 , the rear metal sheet 22 is electrically connected to a metal sheet case 83 (described later) to which an earth wire 16 (described later) is connected, by a metal earth screw 24. The rear metal sheet 22 has a rear metal sheet hook portion 20 and a plurality of main body side fixing screw holes 21 formed therein.

[0020] The rear sheet metal hook portion 20 is an installation portion for installing the housing body 11 of the housing 10 on a wall surface 200, which is an installation surface. The rear sheet metal hook portion 20 is hooked onto a mounting plate hook portion 31 of the mounting plate 30, which will be described later.

[0021] The main body-side fixing screw holes 21 are screw holes through which metal installation screws (not shown) are passed for installing the air purifier 1 on the wall surface 200, and are through-holes that pass through the rear metal sheet 22 in the thickness direction of the rear metal sheet 22. The rear surface 10f of the housing 10 has rear screw holes (not shown) formed at positions corresponding to the main body-side fixing screw holes 21, through which installation screws are passed.

[0022] 4 is a diagram showing the appearance of a mounting plate 30 attached to a wall surface 200 on which the air purifier 1 according to the first embodiment is to be mounted. A metal mounting plate 30, which is a mounting bracket used to install the air purifier 1 on the wall surface 200, is attached to the wall surface 200 on which the air purifier 1 is to be mounted. The mounting plate 30 is attached to the wall surface 200 by, for example, screwing with metal screws. The mounting plate 30 is made of metal to ensure the strength required to mount and hold the housing 10 on the wall surface 200. The mounting plate 30 has a mounting plate hook portion 31 and a mounting bracket-side fixing screw hole 32.

[0023] The mounting plate hook portion 31 is a fitting portion on the mounting plate 30 side that hooks onto the rear sheet metal hook portion 20 formed on the rear surface 10f of the housing 10 and fits into the rear sheet metal hook portion 20. The mounting plate hook portion 31 is a convex portion on which the rear sheet metal hook portion 20 is hooked. On the other hand, the rear sheet metal hook portion 20 formed on the rear sheet metal 22 is a fitting portion on the housing 10 side that hooks onto the mounting plate hook portion 31, which is a fitting portion on the mounting plate 30 side, and fits into the mounting plate hook portion 31.

[0024] The fixing bracket side fixing screw hole 32 is a screw hole into which an installation screw (not shown) is screwed in to fix the air purifier 1 to the wall surface 200. The fixing bracket side fixing screw hole 32 is an internal thread.

[0025] To install the air purifier 1 on the wall surface 200, first, the rear sheet metal hooks 20 formed on the rear sheet metal 22 are hooked onto the mounting plate hooks 31 of the mounting plate 30 installed on the wall surface 200. Then, metal mounting screws are fastened from the front side of the housing main body 11, i.e., from inside the housing main body 11, through the rear screw holes on the rear surface 10f of the housing 10 and the body-side fixing screw holes 21 on the rear sheet metal 22, into the fixing bracket-side fixing screw holes 32. This causes the rear sheet metal hooks 20 to fit into the mounting plate hooks 31, and the rear surface 10f, rear sheet metal 22, and mounting plate 30 are fastened together, thereby installing the housing main body 11 on the wall surface 200, and the air purifier 1 can be installed on the wall surface 200.

[0026] (Internal Configuration of Air Purifier 1) FIG. 5 is a configuration diagram showing an outline of the configuration of air purifier 1 according to embodiment 1, and corresponds to the cross section taken along line V-V in FIG. 2 . FIG. 6 is a configuration diagram showing an outline of the configuration of air purifier 1 according to embodiment 1, and corresponds to the cross section taken along line VI-VI in FIG. 2 . In FIGS. 5 and 6 , some parts are shown as side views and some hatching is omitted for ease of understanding. FIG. 7 is a perspective view showing air purifier 1 in a state where the front panel 12 has been removed from the state shown in FIG. 1 . FIG. 8 is a perspective view showing air purifier 1 in a state where the high-performance dust collecting filter 60 has been removed from the state shown in FIG. 7 . FIG. 9 is a perspective view showing air purifier 1 in a state where the orifice 74 has been removed from the state shown in FIG. 8 .

[0027] 5 to 9 , the air purifier 1 includes a mesh filter 40, an electrostatic precipitator 50, a high-performance dust collecting filter 60, a blower 70, and a circuit unit 80 inside the housing 10. The mesh filter 40, the electrostatic precipitator 50, and the high-performance dust collecting filter 60 are stored in this order in the width direction of the housing 10, from the first side surface 10c on which the air inlet 13 is formed. That is, the mesh filter 40, the electrostatic precipitator 50, and the high-performance dust collecting filter 60 are stored in this order in the direction from the first side surface 10c toward the second side surface 10d.

[0028] The air purifier 1 includes a plurality of electrical components, such as a light-emitting diode (LED), an operation switch, a remote control light receiving unit, a sensor, and an electric dust collector power supply (not shown), inside the housing 10. Each of the electrical components is connected to a low-voltage circuit board 81 (described later) of the circuit unit 80 by electrical wiring.

[0029] The display LED is an array of multiple LEDs and functions as a display unit that displays various information related to the operation of the air purifier 1, such as the operating airflow rate of the air purifier 1 and the level of indoor air pollution. The operation switch is an operation unit for performing operations such as turning the power of the air purifier 1 on or off, adjusting the operating airflow rate of the air purifier 1, and switching between the automatic operation mode and the manual operation mode of the air purifier 1. The sensor is a detection unit that detects dust in the indoor air. The electrostatic precipitator power supply is a power supply unit that supplies high-voltage power for discharging the discharge unit positive electrode 51 (described later) of the electrostatic precipitator 50.

[0030] FIG. 10 is a diagram illustrating the appearance of the mesh filter 40 included in the air purifier 1 according to the first embodiment. The mesh filter 40 removes impurities such as dust from the air drawn into the air purifier 1, filtering and purifying the air drawn into the air purifier 1. Considering the pressure loss of the mesh filter 40, it is preferable to use a material with a coarse mesh for the mesh filter 40. On the other hand, considering the periodic maintenance of the electrostatic precipitator 50 located downwind of the mesh filter 40, the mesh filter 40 preferably has a mesh opening size of approximately 0.5 mm to prevent electrical short circuits caused by dust bridging between the opposite electrodes of the electrostatic precipitator 50. The mesh filter 40 has a flat plate shape, as shown in FIG. 10 .

[0031] FIG. 11 is a diagram illustrating the appearance of the electric dust collector 50 included in the air purifier 1 according to the first embodiment. The electric dust collector 50 has a rectangular parallelepiped shape, for example, as shown in FIG. 11 . As shown in FIG. 5 , the electric dust collector 50 is disposed inside the housing 10 on the first side surface 10c side in the width direction of the housing 10. That is, the electric dust collector 50 is housed inside the housing 10 on the side of the suction port 13 in the width direction of the housing 10. The mesh filter 40 and the electric dust collector 50 are housed inside the housing 10 in this order from the first side surface 10c side on which the suction port 13 is formed in the width direction of the housing 10. That is, the mesh filter 40 and the electric dust collector 50 are housed inside the housing 10 in this order in the direction from the first side surface 10c toward the second side surface 10d. It can be said that the mesh filter 40 and the electric dust collector 50 are housed inside the housing 10 in this order from the upwind side of the airflow drawn into the air purifier 1.

[0032] The electrostatic precipitator 50 removes impurities such as dust particles from the air drawn into the housing 10, thereby purifying the air drawn into the housing 10. The electrostatic precipitator 50 applies an electric charge to various fine particles contained in the air drawn into the housing 10, and attracts the fine particles to a dust collection electrode, thereby capturing the fine particles and purifying the air drawn into the housing 10. That is, the electrostatic precipitator 50 applies a high voltage between the discharge electrode and the dust collection electrode to generate ions by discharge, thereby charging the fine particles passing between the electrodes. The electrostatic precipitator 50 then uses the electric field between the electrodes to attract the fine particles to the dust collection electrode by Coulomb force, thereby collecting them.

[0033] FIG. 12 is a schematic diagram illustrating the principle of electrostatic precipitator (EP) in the air purifier 1 according to the first embodiment. The EP includes a discharge positive electrode 51, a discharge negative electrode 52, and an electrostatic precipitator power supply (not shown). The EP power supply is connected to the discharge positive electrode 51 and the discharge negative electrode 52 via wiring (not shown). When a high voltage is applied between the discharge positive electrode 51 and the discharge negative electrode 52 from the electrostatic precipitator power supply, positively charged ions are generated by corona discharge in a discharge region 53 between the discharge positive electrode 51 and the discharge negative electrode 52. Positively charged particles such as dust particles 54 that are floating around the area bond with the positively charged ions and are attracted to, adhere to, and accumulate on the low-potential discharge negative electrode 52, thereby purifying the air. Therefore, the electric dust collecting unit 50 according to the first embodiment is a positive discharge type electric dust collector.

[0034] 13 is a diagram showing the appearance of the high-performance dust collecting filter 60 included in the air purifier 1 according to the first embodiment. The high-performance dust collecting filter 60 is disposed downstream of the electric dust collector 50 in the air path extending from the air inlet 13 to the air outlet 14 inside the housing 10, i.e., disposed downwind of the electric dust collector 50, and collects dust that could not be collected by the electric dust collector 50. The high-performance dust collecting filter 60 collects finer dust than the dust collected by the mesh filter 40. In other words, the high-performance dust collecting filter 60 has higher collection performance than the mesh filter 40. The high-performance dust collecting filter 60 may be, for example, a High Efficiency Particulate Air (HEPA) filter.

[0035] The high-performance dust collection filter 60 has a flat plate shape, for example, as shown in Fig. 13. The high-performance dust collection filter 60 includes a filter medium 61 and a frame 62. The shape of the high-performance dust collection filter 60 is not limited to the shape shown in Fig. 13.

[0036] The filter material 61 is a collection portion that collects dust, and has a pleated shape made of a sheet material made of an aggregate of resin fibers or glass fibers.

[0037] The frame 62 is a holding portion that holds the filter medium 61 and is made of resin fiber, glass fiber, pulp fiber, or metal. The frame 62 is in contact with the neutralization plate 17 attached to the lower insertion frame portion 19b, which will be described later.

[0038] 1, 3, and 5 to 9, inside the air purifier 1, the high-performance dust-collecting filter 60, the fan 75, the motor 76, and the rear metal plate 22 are arranged in this order from the front panel 12 side toward the rear side. Therefore, when the front panel 12 is removed, the high-performance dust-collecting filter 60 is exposed as shown in Fig. 7. When the high-performance dust-collecting filter 60 is removed from the state shown in Fig. 7, the protective grid 15 and the orifice 74, which will be described later, are exposed as shown in Fig. 8.

[0039] 8 , inside the air purifier 1, a filter storage section 19, which is a filter insertion frame that stores and holds the high-performance dust collecting filter 60, is provided on the front side of the blower 70. That is, inside the housing 10, the filter storage section 19 that stores and holds the high-performance dust collecting filter 60 is provided. The filter storage section 19 has a frame shape that follows the external shape of the high-performance dust collecting filter 60, and is arranged so as to surround the high-performance dust collecting filter 60.

[0040] The filter housing portion 19 is composed of an upper surface side insertion frame portion 19a, a lower surface side insertion frame portion 19b, a first side surface side insertion frame portion 19c, and a second side surface side insertion frame portion 19d.

[0041] The upper surface insertion frame portion 19a is disposed parallel to the upper surface 10a. When the high-performance dust-collecting filter 60 is stored in the filter storage portion 19, the upper surface insertion frame portion 19a comes into contact with the outer surface of the frame 62 of the high-performance dust-collecting filter 60 on the upper surface 10a side, and holds the outer surface.

[0042] The lower surface insertion frame portion 19b is disposed parallel to the lower surface 10b. When the high-performance dust-collecting filter 60 is stored in the filter storage portion 19, the lower surface insertion frame portion 19b comes into contact with the outer surface of the frame 62 of the high-performance dust-collecting filter 60 on the lower surface 10b side, and holds the outer surface.

[0043] The first side surface side insertion frame portion 19c is arranged parallel to the first side surface 10c. When the high-performance dust-collecting filter 60 is stored in the filter storage portion 19, the first side surface side insertion frame portion 19c comes into contact with the outer surface of the frame 62 of the high-performance dust-collecting filter 60 on the first side surface 10c side, and holds the outer surface.

[0044] The second side surface side insertion frame portion 19d is disposed parallel to the second side surface 10d. When the high-performance dust-collecting filter 60 is stored in the filter storage portion 19, the second side surface side insertion frame portion 19d contacts and holds the outer surface of the frame 62 of the high-performance dust-collecting filter 60 on the second side surface 10d side.

[0045] As shown in FIG. 8, a metal neutralization plate 17 is attached to the surface of the lower insertion frame portion 19b that faces the high-performance dust collection filter 60.

[0046] The static eliminator plate 17 is a conductive part having a flat plate shape and made of metal. When the high-performance dust collecting filter 60 is stored in the filter storage part 19, the static eliminator plate 17 faces and contacts the outer surface of the frame 62 of the high-performance dust collecting filter 60 on the lower surface 10b side. Therefore, more specifically, the outer surface of the frame 62 of the high-performance dust collecting filter 60 on the lower surface 10b side is held by the static eliminator plate 17 and the lower surface insertion frame part 19b. The static eliminator plate 17, which is a conductive part, may be made of a conductive resin.

[0047] Fig. 14 is an enlarged view showing the periphery of the protrusion 18 of the static eliminator 17 of the air purifier 1 according to embodiment 1. As shown in Fig. 14, the static eliminator 17 has the protrusion 18 that penetrates an opening (not shown) provided in the lower insertion frame 19b and protrudes from the lower insertion frame 19b toward the underside 10b of the housing 10. That is, a portion of the static eliminator 17 penetrates an opening (not shown) provided in the lower insertion frame 19b and protrudes from the lower insertion frame 19b toward the underside 10b of the housing 10.

[0048] Fig. 15 is an enlarged view showing the grounded rear metal sheet 22 in the air purifier 1 according to the first embodiment. The protrusion 18 of the static eliminator plate 17, which protrudes from the lower insertion frame portion 19b toward the lower surface 10b of the housing 10, is electrically connected to the rear metal sheet 22 by a lead wire 23 shown in Fig. 15. The rear metal sheet 22 is electrically connected to the metal sheet casing 83 by a metal earth screw 24 screwed to the rear metal sheet 22 as shown in Fig. 3. The metal sheet casing 83 is electrically connected to the earth wire 16, which is earthed to the ground, as shown in Fig. 5.

[0049] Therefore, the static eliminator plate 17 is grounded to the ground via the lead wire 23, the rear metal plate 22, the earth screw 24, the metal plate case 83, and the earth wire 16. Therefore, the high-performance dust collecting filter 60 in contact with the static eliminator plate 17 is grounded to the ground via the static eliminator plate 17, the lead wire 23, the rear metal plate 22, the earth screw 24, the metal plate case 83, and the earth wire 16.

[0050] In this way, in the air purifier 1, the high-performance dust collecting filter 60 is electrically connected to the ground and is thus grounded by electrically connecting the high-performance dust collecting filter 60 to the earth wire 16. As a result, in the air purifier 1, the positive (+) ions accumulated in the high-performance dust collecting filter 60 are discharged to the earth through the earth wire 16.

[0051] The blower 70 generates an air flow 45 that is drawn into the housing 10 through the suction port 13, passes through the mesh filter 40, the electrostatic precipitator 50, and the high-performance dust collecting filter 60, and is blown out of the housing 10 through the outlet 14. A centrifugal blower is used as the blower 70. As shown in Fig. 5, the blower 70 has a fan casing 73 that houses a fan 75 and a motor 76 that rotates and drives the fan 75.

[0052] Fan 75 is made of a non-conductive resin and is therefore non-conductive. To achieve a thin product shape for air purifier 1, a centrifugal fan suitable for forming an air path from air inlet 13 through mesh filter 40, electrostatic precipitator 50, and high-performance dust collecting filter 60 to air outlet 14 is used as fan 75.

[0053] The blower 70 is disposed downstream of the high-performance dust collecting filter 60, i.e., downwind of the high-performance dust collecting filter 60, in the air path from the air inlet 13 to the air outlet 14 inside the housing 10. The blower 70 draws air through an air inlet provided on the fan 75 side of the fan casing 73. An orifice 74 is disposed on the front side of the fan casing 73. The orifice 74 is provided with a bell mouth 72 that constitutes the air inlet of the blower 70 and guides the airflow that passes through the high-performance dust collecting filter 60 toward the fan 75 of the blower 70. An air path wall 71 that guides the airflow from the electric precipitator 50 side toward the bell mouth 72 is disposed on the blower 70 side of the electric precipitator 50 and is connected to the surface of the fan casing 73 facing the electric precipitator 50.

[0054] A protective grid 15 is provided on the side of the bell mouth 72 facing the high-performance dust collection filter 60 to prevent the user's fingers from touching the fan 75 when replacing the high-performance dust collection filter 60. The protective grid 15 is fixed to the orifice 74 by screwing a flange portion provided on the outer periphery of the protective grid 15 into the orifice 74 from the front side.

[0055] In air purifier 1, air flows into housing 10 through inlet 13. The air that flows into housing 10 through inlet 13 is drawn into fan 75 through the inlet of blower 70 and blown out toward outlet 14.

[0056] The circuit unit 80 is a component for controlling the operation of the air purifier 1. As shown in FIG. 5 , the circuit unit 80 is disposed inside the housing 10 on the second side surface 10d side in the width direction of the housing 10. That is, the circuit unit 80 is housed inside the housing 10 on the opposite side of the housing 10 from the air inlet 13 in the width direction of the housing 10, with the blower 70 sandwiched between them. The circuit unit 80 controls the operation of the electrical components mounted in the air purifier 1. The circuit unit 80 includes a control circuit for controlling the operation of the air purifier 1, i.e., a control circuit for controlling the motor 76 of the blower 70 and other electrical components mounted in the air purifier 1. The circuit unit 80 includes a high-voltage circuit board 82, a low-voltage circuit board 81, and a sheet metal case 83.

[0057] The high-voltage circuit board 82 is a board on which a high-voltage circuit is mounted. The high-voltage circuit board 82 according to the first embodiment is connected to a power supply connector, and power is supplied from an external power supply. The power supply connector is a portion to which a cable that draws power for the air purifier 1 from an external power supply outside the air purifier 1 is connected. The power supply connector and the external power supply are connected using a cable such as a Vinyl insulated Vinyl sheathed Flat-type (VVF) cable.

[0058] High-voltage circuit board 82 functions as a power generation device that uses power supplied from an external power source to generate drive power for driving motor 76 of blower 70, which has a relatively large drive current value among the electrical components mounted on air purifier 1. High-voltage circuit board 82 supplies the generated drive power to motor 76.

[0059] The low-voltage circuit board 81 is a board on which a low-voltage circuit is mounted. The low-voltage circuit board 81 according to the first embodiment is connected to a power supply connector via a transformer (not shown) and receives power from an external power source. The low-voltage circuit board 81 functions as a power generator that uses power supplied from an external power source to generate drive power for electrical components mounted on the air purifier 1, such as the display LEDs, operation switches, sensors, and electrostatic precipitator 50, which have relatively small drive currents. That is, the low-voltage circuit board 81 functions as a power generator that uses power supplied from an external power source to generate drive power for electrical components with smaller drive currents than the motor 76. The low-voltage circuit board 81 supplies the generated drive power to the electronic components, such as the display LEDs, operation switches, sensors, and electrostatic precipitator 50.

[0060] A high-voltage circuit is a circuit with a voltage exceeding 42.4 V as defined in the IEC-60335 standard of the International Electrotechnical Commission (IEC). A low-voltage circuit is a circuit with a voltage of 42.4 V or less as defined in the IEC-60335 standard.

[0061] Sheet metal case 83 is made of a metal plate and covers and protects high-voltage circuit board 82. Furthermore, sheet metal case 83 is electrically connected to ground wire 16, as shown in Fig. 5. By electrically connecting sheet metal case 83 to ground wire 16, sheet metal case 83 is grounded, and charge generated on high-voltage circuit board 82 is discharged to the ground via ground wire 16. This prevents charging of housing 10 and malfunction of air purifier 1 due to charge generated on high-voltage circuit board 82 in air purifier 1.

[0062] Next, the features of the air purifier 1 according to the first embodiment configured as described above will be described. FIG. 16 is a diagram showing an electrical connection path from the high-performance dust collecting filter 60 to the ground in the air purifier 1 according to the first embodiment. By connecting the high-performance dust collecting filter 60 to a ground wire, the air purifier 1 can prevent charging of the housing 10 due to ions generated by corona discharge in the electrostatic precipitator 50 and charging of the housing 10 due to rotation of the fan 75. That is, the air purifier 1 is provided with a conductive portion that is in contact with the high-performance dust collecting filter 60 and is electrically connected to a ground wire, thereby preventing charging of the housing 10 due to ions generated by corona discharge in the electrostatic precipitator 50 and charging of the housing 10 due to rotation of the fan 75. This allows the air purifier 1 to prevent contamination of the wall surface 200.

[0063] As described above, air purifier 1 includes, inside housing 10, electrostatic precipitator 50 that collects impurities in the air by using ions generated by discharge. Some of the dust 54 that has been charged by ions generated by corona discharge in electrostatic precipitator 50 may not be captured by electrostatic precipitator 50, but may flow through housing 10 with air flow 45 and be captured by high-performance dust collection filter 60.

[0064] In the air purifier 1, the housing 10 and the high-performance dust collecting filter 60 are non-conductive resin components made of non-conductive resin, that is, non-conductive resin molded products. In the air purifier 1, if ions and charges cannot move from the high-performance dust collecting filter 60 toward the ground, when dust 54 charged by ions adheres to the high-performance dust collecting filter 60, the high-performance dust collecting filter 60 becomes charged by the ion-charged dust 54. That is, the high-performance dust collecting filter 60 becomes charged due to ions generated by corona discharge in the electrostatic precipitator 50. The charged high-performance dust collecting filter 60 charges the housing 10, which is made of non-conductive resin and non-conductive. That is, the non-conductive resin housing 10 becomes charged due to the presence of the charged high-performance dust collecting filter 60.

[0065] In this case, an electric field is generated between the charged housing 10 and the wall surface 200 on which the housing 10 is installed, causing dust to be attracted to and adhere to the wall surface 200 around the housing 10, resulting in the problem of the wall surface 200 becoming dirty.

[0066] Furthermore, regardless of the presence or absence of ions generated by corona discharge in the electrostatic precipitator 50, if the fan 75 is made of a non-conductive resin and is therefore non-conductive, the fan 75 will become charged due to friction between the fan 75 and the air. The charged fan 75 will then charge the non-conductive resin housing 10, which is made of a non-conductive resin. In other words, the non-conductive resin housing 10 will become charged due to the presence of the charged fan 75 inside.

[0067] In this case too, an electric field is generated between the charged housing 10 and the wall surface 200 on which the housing 10 is installed, causing dust to be attracted to and adhere to the wall surface 200 around the housing 10, resulting in the problem of the wall surface 200 becoming dirty.

[0068] As described above, one of the reasons why the housing 10 becomes electrically charged is that dust 54 charged by ions generated in the electrostatic precipitator 50 adheres to the high-performance dust collection filter 60, causing the high-performance dust collection filter 60 to become electrically charged. Another reason why the housing 10 becomes electrically charged is that the fan 75 becomes electrically charged due to friction between the fan 75 and the air.

[0069] If the ions generated by corona discharge in the electrostatic precipitator 50 are positive ions, the high-performance dust collection filter 60 and the outer surface of the housing 10 will be positively charged. In this case, the air purifier 1 will be the high-potential side, and the wall surface 200 on which the air purifier 1 is installed will be the low-potential side connected to the ground. If the housing 10 is made of a non-conductive resin and is therefore non-conductive, charge will not easily be discharged from the housing 10 to the grounded wall surface 200, and the housing 10 will remain charged. Therefore, an electric field is generated from the positively charged outer surface of the housing 10 toward the wall surface 200. Then, impurities such as positively charged dust in the air surrounding the wall surface 200 will adhere to the wall surface 200 due to Coulomb force, causing contamination on the wall surface 200.

[0070] Furthermore, when the fan 75 becomes positively charged due to friction between the fan 75 and the air, the outer surface of the housing 10 also becomes positively charged. In this case, the air purifier 1 becomes the high-potential side, and the wall surface 200 on which the air purifier 1 is installed becomes the low-potential side connected to the ground. If the housing 10 is made of a non-conductive resin and is therefore non-conductive, electric charge is less likely to be discharged from the housing 10 to the wall surface 200, which is the ground, and the housing 10 remains charged. Therefore, an electric field is generated from the positively charged outer surface of the housing 10 toward the wall surface 200, and impurities such as positively charged dust in the air surrounding the wall surface 200 adhere to the wall surface 200 due to Coulomb force, causing contamination on the wall surface 200.

[0071] Therefore, in an air purifier 1 having a non-conductive housing 10 made of a resin that is not conductive, the high-performance dust collection filter 60 is grounded, allowing positive (+) charges to move from the high-performance dust collection filter 60 toward the ground.

[0072] In the air purifier 1, the material of the filter medium 61 of the high-performance dust collection filter 60 is resin fiber or glass fiber. The material of the frame 62 of the high-performance dust collection filter 60 is resin fiber, glass fiber, pulp fiber, or metal.

[0073] The frame 62 of the high-performance dust-collecting filter 60 is in contact with the static eliminator plate 17 attached to the filter housing portion 19. Specifically, the frame 62 of the high-performance dust-collecting filter 60 is in contact with the static eliminator plate 17 attached to the lower surface insertion frame portion 19b arranged on the lower surface 10b side in the filter housing portion 19.

[0074] A part of the static eliminator plate 17 penetrates an opening provided in the lower surface insertion frame portion 19b and protrudes from the lower surface insertion frame portion 19b toward the lower surface 10b of the housing 10. Specifically, the static eliminator plate 17 has a protrusion 18 that penetrates an opening provided in the lower surface insertion frame portion 19b and protrudes from the lower surface insertion frame portion 19b toward the lower surface 10b of the housing 10.

[0075] The protrusion 18 of the static eliminator plate 17 is electrically connected to the rear metal sheet 22 by a lead wire 23. The rear metal sheet 22 is electrically connected to the metal sheet case 83 by a metal earth screw 24 screwed to the rear metal sheet 22. The metal sheet case 83 is then electrically connected to the earth wire 16 that is earthed to the ground.

[0076] Therefore, the static eliminator plate 17 is grounded to the ground via the lead wire 23, the rear metal plate 22, the earth screw 24, the metal plate case 83, and the earth wire 16. Therefore, the high-performance dust collecting filter 60 in contact with the static eliminator plate 17 is grounded to the ground via the static eliminator plate 17, the lead wire 23, the rear metal plate 22, the earth screw 24, the metal plate case 83, and the earth wire 16.

[0077] In the air purifier 1 having the electrical connection path described above, the high-performance dust collecting filter 60 is electrically connected to the ground and is thus grounded by electrically connecting the high-performance dust collecting filter 60 to the earth wire 16. As a result, in the air purifier 1, the positive (+) ions accumulated in the high-performance dust collecting filter 60 are discharged to the earth through the earth wire 16, so that the positive (+) ions charged in the high-performance dust collecting filter 60 are efficiently discharged and the high-performance dust collecting filter 60 and the housing 10 are prevented from becoming charged.

[0078] Furthermore, in the air purifier 1 having the electrical connection path described above, the housing 10 is in contact with the rear metal sheet 22, and therefore the housing 10 is electrically connected to the ground and grounded by electrically connecting the rear metal sheet 22 to the earth wire 16. As a result, in the air purifier 1, the positive (+) charge accumulated in the housing 10 is discharged to the earth through the earth wire 16, so that the positive (+) charge accumulated in the housing 10 is efficiently discharged and the housing 10 is prevented from becoming charged.

[0079] As a result, in the air purifier 1, the housing 10 is prevented from becoming charged, thereby preventing the occurrence of dirt on the wall surface 200 due to the electric field that occurs between the charged housing 10 and the wall surface 200 on which the housing 10 is installed, and preventing dirt from forming on the wall surface 200 on the back side of the air purifier 1 and the wall surface 200 around the air purifier 1.

[0080] Furthermore, even if fan 75, which is made of a non-conductive resin and therefore non-conductive, becomes charged due to friction between the fan 75 and the air, the electric field generated by fan 75 is shielded by grounded high-performance dust collection filter 60, preventing charging of housing 10. As a result, in air purifier 1, charging of housing 10 is prevented, thereby preventing the occurrence of dirt on wall surface 200 due to the electric field generated between charged fan 75 and wall surface 200, and preventing dirt from being generated on wall surface 200 behind air purifier 1 and on wall surfaces 200 around air purifier 1. In other words, in air purifier 1, the same effect as so-called electrostatic shielding is obtained for fan 75.

[0081] Furthermore, in the air purifier 1, the housing 10 is mounted to the wall surface 200 by fastening together the rear metal sheet 22 and the mounting plate 30 attached to the rear surface 10f using metal mounting screws. That is, the housing 10 of the air purifier 1 is screwed to the metal mounting plate 30, which is a mounting bracket fixed to the wall surface 200 with metal screws. As a result, in the air purifier 1, the positive (+) charge accumulated in the housing 10 is discharged through the rear metal sheet 22 and the mounting plate 30 to the wall surface 200, which is ground, so that the positive (+) charge accumulated in the housing 10 is efficiently discharged and the housing 10 is prevented from becoming charged up.

[0082] Furthermore, in the air purifier 1, the air outlet 14 is provided only on the top surface 10a, which is one surface of the housing 10. That is, in the air purifier 1, the direction in which purified air is blown out from the air purifier 1 is only one direction. Therefore, there are no significant limitations on the placement position of the air purifier 1 on the wall surface 200 inside the room.

[0083] As described above, in the air purifier 1 according to the first embodiment, by connecting the high-performance dust collecting filter 60 to the earth wire 16, it is possible to prevent charging of the housing 10 due to ions generated by corona discharge in the electrostatic precipitator 50 and charging of the housing 10 due to the rotation of the fan 75. This allows the air purifier 1 to prevent the wall surface 200 from becoming dirty.

[0084] Therefore, the air purifier 1 according to the first embodiment has the effect of preventing contamination of the installation surface caused by static electricity of the components of the air purifier 1, regardless of the direction of air discharge.

[0085] The configurations shown in the above embodiments are merely examples, and may be combined with other known technologies, and parts of the configurations may be omitted or modified without departing from the spirit of the invention.

[0086] DESCRIPTION OF SYMBOLS 1 Air purifier, 10 Housing, 10a Top surface, 10b Bottom surface, 10c First side surface, 10d Second side surface, 10e Front surface, 10f Back surface, 11 Housing body, 12 Front panel, 13 Intake port, 14 Outlet port, 15 Protective grid, 16 Ground wire, 17 Discharge plate, 18 Protrusion, 19 Filter storage section, 19a Top side insertion frame section, 19b Bottom side insertion frame section, 19c First side side insertion frame section, 19d Second side side insertion frame section, 20 Rear plate metal hook section, 21 Main body side fixing screw hole, 22 Rear plate metal, 23 Lead wire, 24 Ground screw, 30 Mounting plate, 31 Mounting plate hook section, 32 Fixing bracket side fixing screw hole, 40 Mesh filter, 45 Air flow, 50 Electrostatic precipitator, 51 Discharge section positive electrode, 52 discharge section negative electrode, 53 discharge area, 54 dust, 60 high-performance dust collection filter, 61 filter material, 62 frame, 70 blower, 71 air passage wall, 72 bell mouth, 73 fan casing, 74 orifice, 75 fan, 76 motor, 80 circuit section, 81 low-voltage circuit board, 82 high-voltage circuit board, 83 sheet metal case, 200 wall surface.

Claims

1. An air purifier that is installed on an indoor installation surface and purifies the air in the room, comprising: a non-conductive housing having an inlet for drawing in air and an outlet for blowing out the air; a blower housed in the housing and generating an airflow that draws in the air from the inlet and blows out the air from the outlet; and a filter housed in the housing and removes impurities in the airflow, wherein the filter is grounded.

2. The air purifier according to claim 1, comprising: an earth wire; and a conductive part in contact with the filter and having conductivity, the conductive part being electrically connected to the earth wire.

3. The air purifier according to claim 2, further comprising a filter storage section that is housed in the housing and stores the filter, wherein the conductive portion has a flat plate shape and is attached to the filter storage section, and has a protrusion that penetrates the filter storage section, protrudes to the outside of the filter storage section, and is electrically connected to the earth wire.

4. The air purifier according to claim 3, wherein the filter storage section has an opening through which the protrusion passes.

5. The air purifier according to any one of claims 2 to 4, wherein the conductive portion is made of metal.

6. The air purifier according to any one of claims 2 to 4, wherein the conductive portion is made of a conductive resin having electrical conductivity.

7. The air purifier according to any one of claims 1 to 6, further comprising a discharge-type electric dust collector housed in the housing for removing impurities from the air flow.

8. The air purifier according to any one of claims 1 to 7, wherein the housing is screwed to a mounting bracket that is fixed to the mounting surface by a metal screw.

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