CN211204244U

CN211204244U - Fresh air device

Info

Publication number: CN211204244U
Application number: CN201922427455.2U
Authority: CN
Inventors: 任智星
Original assignee: Beijing Green Bass Decoration Engineering Co ltd
Current assignee: Beijing Green Bass Decoration Engineering Co ltd
Priority date: 2019-12-26
Filing date: 2019-12-26
Publication date: 2020-08-07
Anticipated expiration: 2029-12-26

Abstract

The utility model relates to a fresh air device, which comprises an indoor unit arranged indoors and an outdoor unit arranged outdoors, wherein the outdoor unit of the indoor unit is communicated with each other through a pipeline, an exhaust cavity and an air supply cavity are arranged in the indoor unit, the air supply cavity is positioned above the exhaust cavity, an upper top wall in the air supply cavity is communicated with the outside, a filter screen box is also arranged in the air supply cavity, a filter screen for filtering air is folded in the filter screen box, and a plurality of through holes for accommodating the filter screen box to slide out are arranged in the air supply cavity corresponding to the side wall of the indoor unit; an exhaust fan used for providing suction force for the exhaust cavity and a blower used for blowing air into the room through the air supply cavity are arranged in the outdoor unit. The utility model discloses have the effect of being convenient for change the filter screen.

Description

Fresh air device

Technical Field

The utility model belongs to the technical field of indoor air purification's technique and specifically relates to a new trend device is related to.

Background

The fresh air device is also called a fresh air system, is a set of independent air processing system consisting of an air supply system and an air exhaust system, and can be divided into a pipeline type fresh air device and a non-pipeline type fresh air device.

Take pipeline formula new trend device as an example, inhale outdoor air among the air supply system to make it filter through the filter screen, then blow to indoor, exhaust system can discharge indoor dirty air outdoor, makes indoor circulation of air through new trend device, thereby has improved indoor air quality.

However, the new trend device can pile up a lot of on the filter screen and block thing and dust after using for a long time, and too much debris influence the gas permeability of filter screen on the one hand, and on the other hand makes the absorption filter effect of filter screen reach the saturation, and the filter capacity of filter screen reduces, so change the filter screen at need regularly, and current filter screen need take out the filter screen with the whole machine of taking apart of machine when changing, and this has led to the fact inconveniently for the change of filter screen.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art exists, the utility model aims at providing a new trend device, it has the effect of being convenient for change the filter screen.

The above utility model discloses an above-mentioned utility model's purpose can be realized through following technical scheme:

a fresh air device comprises an indoor unit arranged indoors and an outdoor unit arranged outdoors, wherein the outdoor unit of the indoor unit is communicated with each other through a pipeline, an exhaust cavity and an air supply cavity are arranged in the indoor unit, the air supply cavity is positioned above the exhaust cavity, an upper top wall in the air supply cavity is communicated with the outside, a filter screen box is also arranged in the air supply cavity, a filter screen for filtering air is folded in the filter screen box, and a plurality of through holes for accommodating the filter screen box to slide out are formed in the air supply cavity corresponding to the side wall of the indoor unit; an exhaust fan used for providing suction force for the exhaust cavity and a blower used for blowing air into the room through the air supply cavity are arranged in the outdoor unit.

Through adopting above-mentioned technical scheme, when new trend device began work, the exhaust fan was taken out indoor dirty air to the forced draught blower insufflates indoor with outdoor fresh air, thereby accomplished the work that promotes indoor circulation of air to indoor air renewal. Improves the indoor environment and improves the living quality of people. After the new trend device is used for a long time, can pile up a large amount of dusts and miscellaneous bits in the filter screen of filter screen box, the staff can take out filter screen box from the through-hole this moment, then washs and replaces the filter screen in the filter screen box to the convenience that the filter screen was changed has been improved.

The present invention may be further configured in a preferred embodiment as: and a sliding rail for supporting the filter screen box is fixedly connected to the side wall of the air supply cavity.

Through adopting above-mentioned technical scheme, the slide rail has played the fixed effect of bearing to the filter screen box for filter screen box places more stable when the air supply intracavity portion, has improved the convenience when the user takes the filter screen box out from the through-hole.

The present invention may be further configured in a preferred embodiment as: the side wall of the filter screen box is fixedly connected with a sealing plate which covers the through hole, the sealing plate is provided with a connecting screw in a penetrating way, and the indoor unit is provided with a connecting screw hole which is matched with the connecting screw.

Through adopting above-mentioned technical scheme, the lid of closing plate is established on the through-hole, and screw-thread fit between through connecting screw and connection screw makes the diapire of closing plate and seal groove support each other and lean on to compress tightly to the leakproofness of filter screen box with the through-hole junction has been improved.

The present invention may be further configured in a preferred embodiment as: the outer edge of through-hole department sets up a seal groove that is used for holding the closing plate, the connection screw sets up on the connecting groove diapire.

Through adopting above-mentioned technical scheme, the setting up of seal groove makes inside the closing plate can imbed into the seal groove to improve the wholeness of indoor set on the one hand, reduced because the closing plate salient collide with and damage that causes in the off-premises station, thereby on the other hand the closing plate embedding is gone into in the seal groove and is mutually extruded with the seal groove diapire and further improved the leakproofness that the closing plate lid was established in through-hole department.

The present invention may be further configured in a preferred embodiment as: the bottom wall of the sealing groove is provided with a containing hole, and a compression spring for pushing the sealing plate out of the sealing groove is arranged in the containing hole.

Through adopting above-mentioned technical scheme, when the closing plate was established the sealed capping, compression spring's one end top was touched at the diapire of accommodation hole, and the other end top is touched on the closing plate, and compression spring was in by compression state this moment, revolves the connecting screw when the staff for when connecting screw and connecting screw break away from each other, compression spring was automatic ejecting from the seal groove with the closing plate, thereby has improved the convenience when the staff safeguarded the filter screen box.

The present invention may be further configured in a preferred embodiment as: the filter screen boxes are at least provided with two filter screens along the height direction, and the mesh number of the filter screens in the filter screen boxes is gradually increased from bottom to top.

Through adopting above-mentioned technical scheme, the setting of multiunit filter screen box makes the air that blows off from the air supply chamber need pass through the multilayer and filter to the air-purifying capacity of indoor set to air has been improved. When the air passes through the plurality of filter screen boxes, the filter screens at different positions have different meshes, so that particles with different diameters in the air can be sequentially filtered from large to small, and the air purifying capacity of the indoor unit is further improved.

The present invention may be further configured in a preferred embodiment as: the lower bottom wall of the air supply cavity is fixedly connected with a distribution box which can make air uniformly distributed in the air supply cavity, and a plurality of distribution plates which can guide the air are uniformly and fixedly connected in the distribution box.

Through adopting above-mentioned technical scheme, blow into the branch flow box inside from first blast pipe when the air to divided into a plurality of strands by the flow distribution plate, then evenly blow to the filter screen box. The distribution of the air in the air supply cavity is more uniform through the arrangement of the splitter plate, and all positions on the filter screen box are more uniformly contacted with the airflow, so that the filtering efficiency is improved; and the flow distribution box can also make the air blown out of the outdoor unit more uniform, thereby improving the working stability of the indoor unit.

The present invention may be further configured in a preferred embodiment as: the side wall of the air exhaust cavity is communicated with the outside, the side wall of the outdoor unit is fixedly connected with a plurality of baffle sheets for preventing sundries from entering the air exhaust cavity, and the baffle sheets are obliquely and downwards arranged.

Through adopting above-mentioned technical scheme, the setting of separation blade can block debris, has reduced the condition that debris entered into the intracavity portion of airing exhaust.

To sum up, the utility model discloses a following at least one useful technological effect:

1. the convenience of the fresh air device in replacing the filter screen is improved, and the filter screen box is arranged through the through holes; the filter screen box can be directly drawn out of the through hole by workers, so that the filter screen can be conveniently replaced by the workers;

2. the convenience when taking out the filter screen box is improved, through compression spring's setting, when the staff revolves to twist connecting screw to connecting screw and break away from each other, compression spring pops out the closing plate from the seal groove in automatic to the staff has made things convenient for and has taken out the filter screen box in the through-hole.

Drawings

FIG. 1 is a schematic view of the overall structure of a fresh air device;

FIG. 2 is a schematic view showing the overall structure of the heat exchange assembly;

FIG. 3 is a schematic view showing the connection relationship of the heat exchange assemblies;

fig. 4 is a schematic view showing an internal structure of an outdoor unit;

fig. 5 is a schematic view showing the internal mechanism of the indoor unit;

FIG. 6 is a schematic view of the mechanism showing the connection between the filter screen box and the indoor unit;

fig. 7 is a sectional view showing the filter cartridge and the filter.

In the figure, 1, an indoor unit; 11. an exhaust chamber; 12. an air supply cavity; 121. a through hole; 13. a filter screen box; 131. a filter screen; 14. a slide rail; 15. a sealing groove; 151. a connecting screw hole; 152. an accommodation hole; 153. a compression spring; 16. a sealing plate; 161. a connecting screw; 17. a shunt box; 171. a flow distribution plate; 18. a partition plate; 19. a baffle plate; 2. a heat exchange assembly; 21. a first exhaust duct; 22. an outer heat exchange tube; 23. a second exhaust duct; 24. a first blast pipe; 25. a heat exchange inner tube; 26. a second blast pipe; 27. sealing the cover; 271. an air supply hole; 272. an air exhaust hole; 273. a seal ring; 274. connecting grooves; 275. a connecting plate; 3. an outdoor unit; 31. a housing; 32. an exhaust fan; 33. an air exhaust duct; 34. a blower; 35. an air supply duct; 36. an object blocking net; 37. a weather edge; 4. a wall.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, in order to the present invention, the fresh air device includes an indoor unit 1 placed indoors, an outdoor unit 3 placed outdoors, and a heat exchange assembly 2 disposed in a wall 4 and communicating the indoor unit 1 and the outdoor unit 3 with each other, wherein a blower 34 (shown in fig. 4) blowing air into the indoor unit and an exhaust fan 32 (shown in fig. 4) exhausting indoor air to the outdoor unit are disposed in the outdoor unit 3. When the fresh air device works, dirty indoor air can be sucked out through the suction force of the exhaust fan 32, and outdoor fresh air is blown into the room through the blower 34, so that the effect of ventilating the room is achieved.

As shown in fig. 2 and 3, the heat exchange assembly 2 includes a first exhaust duct 21, a heat exchange outer duct 22, and a second exhaust duct 23 connected in sequence; the first exhaust duct 21 is connected to the indoor unit 1, and the second exhaust duct 23 is connected to the outdoor unit 3. The heat exchange component 2 further comprises a first air supply pipe 24, a heat exchange inner pipe 25 and a second air supply pipe 26 which are sequentially connected in an initial position; the first air supply pipe 24 is connected with the indoor unit 1, the second air supply pipe 26 is connected with the outdoor unit 3, and the heat exchange inner pipe 25 is made of a copper pipe. The heat exchange inner tube 25 is spirally wound around the inner peripheral surface of the heat exchange outer tube 22, and both ends of the heat exchange inner tube 25 extend out from the end of the heat exchange outer tube 22. The first air supply pipe 24, the second air supply pipe 26, the first exhaust pipe 21 and the second exhaust pipe 23 are made of hose materials. The both ends of heat transfer outer tube 22 respectively are provided with carries out the closing cap 27 of shutoff with heat transfer outer tube 22, and the outer peripheral face that heat transfer outer tube 22 is close to the tip has seted up the external screw thread, corresponds to set up on the closing cap 27 with the internal thread that heat transfer outer tube 22 mutually supported, closing cap 27 can be fixed on heat transfer outer tube 22 through the screw-thread fit between with heat transfer outer tube 22. The cover 27 has an air supply hole 271 and an air exhaust hole 272 formed on the surface thereof, wherein the air supply hole 271 is located at the center of the cover 27, and the air exhaust hole 272 is located at a position of the cover 27 deviated from the center.

As shown in fig. 2 and 3, an end of the heat exchange inner tube 25 vertically penetrates through the air blowing hole 271, and communicates with the first air blowing tube 24 or the second air blowing tube 26, and a rubber packing 273 is further fixed to an inner circumferential surface of the air blowing hole 271. When the end of the heat exchange inner tube 25 passes through the air blowing hole 271, the outer circumferential surface of the heat exchange inner tube 25 presses the sealing ring 273, so that the sealing ring 273 is elastically deformed and filled in a gap at the joint of the air blowing hole 271 and the heat exchange inner tube 25, and the sealing performance of the sealing cover 27 and the heat exchange inner tube 25 is improved. A connecting groove 274 is formed in the outer edge of the exhaust hole 272, a connecting plate 275 is fixedly connected to the end portions, facing the heat exchange outer pipe 22, of the first exhaust pipe 21 and the second exhaust pipe 23, the connecting plate 275 can be clamped into the connecting groove 274 and fixed to the bottom wall of the connecting groove 274 through bolts, and therefore the first exhaust pipe 21 and the second exhaust pipe 23 are fixedly communicated with the heat conduction outer pipe respectively. The mutual cooperation of connecting plate 275 and connecting groove 274 has improved first exhaust pipe 21, and the stability on the shrouding is fixed to second exhaust pipe 23 to connecting plate 275 is by the inseparable compaction of bolt on the diapire of connecting groove 274, thereby has improved the leakproofness of heat transfer outer tube 22 when respectively with first exhaust pipe 21, second exhaust pipe 23 intercommunication.

When a worker installs the heat exchange assembly 2, the heat exchange inner tube 25 is first inserted into the heat exchange outer tube 22, and the cap 27 is screwed to the end of the heat exchange outer tube 22. At this time, the sealing ring 273 is pressed by the heat exchange inner tube 25 to seal the blowing hole 271, and then the worker fixedly attaches the first blowing pipe 24 and the second blowing pipe 26 to both ends of the heat exchange inner tube 25, respectively. Finally, the connecting plates 275 on the first exhaust duct 21 and the second exhaust duct 23 are clamped into the corresponding connecting grooves 274, the bolts are screwed, and the connecting plates 275 are pressed in the connecting grooves 274 through the threaded fit between the bolts and the sealing cover 27, at this time, the first air supply duct 24 and the first exhaust duct 21 are positioned on the same side of the heat exchange outer tube 22.

When air passes through the heat exchange inner tube 25 from the second blowing tube 26 and is blown to the first blowing tube 24, the first exhaust duct 21 blows indoor air to the heat exchange outer tube 22, and the air inside the heat exchange inner tube 25 and the air outside the heat exchange inner tube 25 exchange heat through the copper heat exchange inner tube 25. In summer and when there is the air conditioner refrigeration indoor, the blast pipe blows outdoor hot air and indoor cold air that blows off to heat transfer inner tube 25 and carries out the heat transfer through the copper pipe to make the inside hot air temperature of heat transfer inner tube 25 descend, reduced indoor cold source and run off, played energy-conserving effect, when winter, heat exchange assembly 2 works with the same principle, make and blow in indoor cold air temperature from outdoor and rise, reduced indoor thermal loss. The spirally wound heat exchange inner tube 25 increases the surface area of the heat exchange inner tube 25, thereby improving the heat exchange efficiency of the heat exchange inner tube 25. The heat exchange inner pipe 25 is a copper pipe, and the copper material has good heat conductivity, so that the heat exchange efficiency of the heat exchange inner pipe 25 is further improved.

As shown in fig. 4, the outdoor unit 3 includes a casing 31, and a discharge fan 32 and a blower 34 are respectively fixed to an inner sidewall of the casing and communicate with the corresponding second discharge duct 23 and second blowing duct 26. The exhaust fan 32 is located above the blower 34, and the exhaust fan 32 is further communicated with an exhaust air duct 33, and the other end of the exhaust air duct 33 extends out of the blower 34 and is provided with an upward opening. The blower 34 is connected to a blower duct 35, and one end of the blower duct 35 extends out of the outdoor unit 3 and is provided with a downward opening. The openings of the air supply duct 35 and the air exhaust duct 33 are fixedly connected with a cobweb-shaped object blocking net 36, and the arrangement of the object blocking net 36 can block the ports of the air supply duct 35 and the air exhaust duct 33, so that the situation that sundries enter the air duct is reduced. Because the opening of the air exhaust duct 33 is arranged upward, rainwater can enter the outdoor unit 3 from the opening of the air exhaust duct 33 when raining, a wind and rain edge 37 is further fixedly connected to the port of the air exhaust duct 33, and the wind and rain edge 37 is fixedly connected to the object blocking net 36 in the air exhaust duct 33. The arrangement of the wind and rain edge 37 can shield the port of the air exhaust duct 33, thereby reducing the occurrence of rainwater entering the inside of the air exhaust duct 33. The openings of the exhaust air duct 33 and the supply air duct 35 are disposed opposite to each other, so that the dirty air discharged from the exhaust air duct and the air sucked into the supply air duct 35 are not easily interfered with each other, thereby improving the working stability of the outdoor unit 3.

As shown in fig. 5 and 6, an exhaust cavity 11 and an air supply cavity 12 are formed inside the indoor unit 1, and the exhaust cavity 11 is located below the air supply cavity 12; the top of the indoor unit 1 is provided with an opening and is communicated with the interior of the air supply cavity 12; the side wall of the indoor unit 1 is provided with an opening near the ground and is communicated with the inside of the air exhaust cavity 11. The first blast pipe 26 communicates with the blast chamber 11, and the first exhaust pipe 21 communicates with the exhaust chamber 12. The side wall of the indoor unit 1 is provided with a through hole 121 towards the air exhaust cavity 11, a filter screen box 13 is inserted into the through hole 121, a filter screen 131 (shown in fig. 7) is placed in the filter screen box 13, and the filter screen 131 is filled in the filter screen box 13 in an organ type folding manner. The through holes 121 are three in the height direction of the indoor unit 1, three corresponding to the filter screen boxes 13 are provided, and the mesh number of the filter screens 131 in the three filter screen boxes 13 is gradually increased from bottom to top.

After the new trend device is used for a long time, can pile up a large amount of dusts and miscellaneous bits in the filter screen 131 of filter screen box 13, the staff can take filter screen box 13 out from through-hole 121 this moment, then wash and replace filter screen 131 in filter screen box 13 to the convenience that filter screen 131 changed has been improved. The arrangement of the filter screen boxes 13 makes the air blown out from the blowing chamber 12 need to be filtered by multiple layers, thereby improving the air purifying capacity of the indoor unit 1. When the air passes through the plurality of filter screen boxes 13, the filter screens 131 at different positions have different meshes, so that particles with different diameters in the air can be sequentially filtered from large to small, and the air purifying capacity of the indoor unit 1 is further improved.

As shown in fig. 5 and 6, two side walls adjacent to the side wall where the through hole 121 is located in the air supply cavity 12 are respectively and fixedly connected with a sliding rail 14, each sliding rail 14 includes a horizontal plate and a vertical plate which are fixedly connected with each other, the vertical plates are fixedly connected with the inner side wall of the air supply cavity 12, the upper surface of the horizontal plate is flush with the side wall of the through hole 121 close to the ground, and the filter screen box 13 can slide on the surface of the sliding rail 14. Slide rail 14 has played the fixed effect of bearing to filter screen box 13 for filter screen box 13 places more stable when air supply chamber 12 is inside, has improved the convenience when the user takes filter screen box 13 out from through-hole 121.

As shown in fig. 5 and 6, a sealing plate 16 is fixedly connected to a side wall of the filter screen box 13 close to the through hole 121, the sealing plate 16 can cover the through hole 121, a sealing groove 15 is formed at an outer edge of the through hole 121, the sealing plate 16 can be embedded into the sealing groove 15, at this time, one surface of the sealing plate 16 departing from the filter screen box 13 is flush with the indoor unit 1, a connecting screw 161 penetrates through the sealing plate 16, and a connecting screw hole 151 in threaded fit with the connecting screw 161 is formed in a bottom wall of the sealing groove 15. The cover of the sealing plate 16 is arranged on the through hole 121 and the sealing plate 16 is fixed in the sealing groove 15, and the sealing plate 16 and the bottom wall of the sealing groove 15 are pressed against each other through the thread fit between the connecting screw 161 and the connecting screw hole 151, so that the sealing performance of the joint of the filter screen box 13 and the through hole 121 is improved. The sealing groove 15 is arranged to enable the sealing plate 16 to be embedded into the sealing groove 15, so that on one hand, the integrity of the indoor unit 1 is improved, and the collision and damage caused by the fact that the sealing plate 16 protrudes out of the outdoor unit 3 are reduced, and on the other hand, the sealing plate 16 is embedded into the sealing groove 15 and mutually extrudes with the bottom wall of the sealing groove 15, so that the sealing performance of the sealing plate 16 covering the through hole 121 is further improved.

As shown in fig. 5 and 6, since the sealing plate 16 is embedded in the sealing groove 15, it is not easy for a worker to take out the sealing plate when mounting the sealing plate, and in order to optimize the above problem, two receiving holes 152 are further formed in the bottom wall of the sealing groove 15, and a compression spring 153 is disposed in the receiving hole 152. When the sealing plate 16 covers the sealing groove 15, one end of the compression spring 153 abuts against the bottom wall of the accommodating hole 152, the other end of the compression spring 153 abuts against the sealing plate 16, the compression spring 153 is in a compressed state, and when a worker screws the connecting screw 161, so that the connecting screw 161 and the connecting screw hole 151 are separated from each other, the compression spring 153 automatically ejects the sealing plate 16 out of the sealing groove 15, and therefore the convenience of the worker in maintaining the filter screen box 13 is improved.

As shown in fig. 5, the first air supply pipe 24 penetrates into the air supply cavity 12, the end of the first air supply pipe 24 is connected with a diversion box 17, the diversion box 17 is arranged in a funnel shape with two side openings, the first air supply pipe 24 is communicated with the small openings of the diversion box 17, the large opening of the diversion box 17 is arranged towards the filter screen box 13, a plurality of diversion plates 171 are uniformly fixedly connected in the diversion box 17, when air is blown into the diversion box 17 from the first air supply pipe 24, and the air is divided into a plurality of strands by the diversion plates 171 and then uniformly blown to the filter screen box 13. The distribution of the air in the air supply cavity 12 is more uniform through the arrangement of the flow dividing plate 171, so that the contact between each position on the filter screen box 13 and the air flow is more uniform, and the filtering efficiency is improved; and the shunting box 17 can also make the air that is blown out of the outdoor unit 3 out more even, has improved the stability of indoor unit 1 work. A partition plate 18 is fixedly connected to an opening at the upper end of the air supply cavity 12, and the partition plate 18 can reduce the occurrence of the situation that sundries fall into the air supply cavity 12. The first exhaust duct 21 is communicated with the exhaust cavity 11, and a plurality of parallel baffle plates 19 are fixedly connected at the outlet of the exhaust cavity 11, and the baffle plates 19 are obliquely and downwards arranged. The baffle plate 19 can block sundries, and the condition that the sundries enter the air exhaust cavity 11 is reduced.

The implementation principle of the embodiment is as follows: when the fresh air device works, the air feeder 34 can feed outdoor fresh air into and out of the room, and the exhaust fan 32 can suck out indoor dirty air, so that the indoor air is purified. Air supply air current and air exhaust air current when passing through heat transfer assembly 2, respectively with the heat transfer inner tube 25 inside and outside global contact to carry out the heat transfer, make air supply air current's temperature more be close to indoor temperature, thereby reduced because new trend device work has caused indoor temperature to change by a wide margin. When the indoor unit 1 needs to replace the filter screen after long-term use, a worker can screw the connecting screw 161, and the connecting screw 161 and the connecting screw hole 151 are separated from each other, and at this time, the compression spring 153 ejects the sealing plate 16, so that the worker can replace the filter screen box 13 conveniently.

The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. The utility model provides a new trend device, is including setting up indoor set (1) indoor, sets up at outdoor off-premises station (3), and indoor set (1) off-premises station (3) communicate each other through the pipeline, its characterized in that: an air exhaust cavity (11) and an air supply cavity (12) are formed in the indoor unit (1), the air supply cavity (12) is located above the air exhaust cavity (11), an upper top wall in the air supply cavity (12) is communicated with the outside, a filter screen box (13) is further arranged in the air supply cavity (12), a filter screen (131) for filtering air is folded in the filter screen box (13), and a plurality of through holes (121) for allowing the filter screen box (13) to slide out are formed in the air supply cavity (12) corresponding to the side wall of the indoor unit (1); an exhaust fan (32) for providing suction to the exhaust cavity (11) and a blower (34) for blowing air into the room through the blowing cavity (12) are arranged in the outdoor unit (3).

2. The fresh air device as claimed in claim 1, wherein: and a sliding rail (14) for supporting the filter screen box (13) is fixedly connected to the side wall of the air supply cavity (12).

3. The fresh air device as claimed in claim 1, wherein: the side wall of the filter screen box (13) is fixedly connected with a sealing plate (16) covering the through hole (121), the sealing plate (16) is provided with a connecting screw (161) in a penetrating way, and the indoor unit (1) is provided with a connecting screw hole (151) matched with the connecting screw (161).

4. A fresh air device according to claim 3, wherein: the outer edge of the through hole (121) is provided with a sealing groove (15) for accommodating a sealing plate (16), and the connecting screw hole (151) is formed in the bottom wall of the connecting groove (274).

5. The fresh air device as claimed in claim 4, wherein: the bottom wall of the sealing groove (15) is provided with a containing hole (152), and a compression spring (153) for pushing the sealing plate (16) out of the sealing groove (15) is arranged in the containing hole (152).

6. The fresh air device as claimed in claim 1, wherein: the filter screen boxes (13) are at least provided with two filter screen boxes (13) along the height direction, and the mesh number of the filter screens (131) in the filter screen boxes (13) is gradually increased from bottom to top.

7. The fresh air device as claimed in claim 1, wherein: the lower bottom wall of the air supply cavity (12) is fixedly connected with a shunting box (17) which enables air to be uniformly distributed in the air supply cavity (12), and a plurality of shunting plates (171) which guide air are uniformly and fixedly connected in the shunting box (17).

8. The fresh air device as claimed in claim 1, wherein: the side wall of the air exhaust cavity (11) is communicated with the outside, baffle plates (19) used for preventing sundries from entering the air exhaust cavity (11) are fixedly connected to the side wall of the outdoor unit (3), and a plurality of baffle plates (19) are obliquely and downwards arranged.