CN211119551U

CN211119551U - Fan system and range hood with same

Info

Publication number: CN211119551U
Application number: CN201920904713.9U
Authority: CN
Inventors: 徐鑫; 陈浩辉; 刘杰; 黄友根; 申志贤
Original assignee: Ningbo Fotile Kitchen Ware Co Ltd
Current assignee: Ningbo Fotile Kitchen Ware Co Ltd
Priority date: 2019-01-14
Filing date: 2019-06-14
Publication date: 2020-07-28
Anticipated expiration: 2029-06-14
Also published as: CN111435003A; CN212378030U

Abstract

The utility model relates to a fan system and applied range hood that has this fan system, the fan system includes the spiral case, the impeller, motor and motor support, the impeller can be located in the spiral case with rotating, the motor passes through motor support mounting on the spiral case and power take off end is connected with the impeller, interval arrangement's front bezel and back plate around the spiral case has, it has the air intake to open on the front bezel, it has the first installing port that can supply the impeller to pass to open on the back plate, motor support takes shape to discoid and shirk the formula and locates this first installing port department, the motor shirks the formula and locates on the motor support. The utility model discloses a fan system when dismantling, pull down motor support from the spiral case back plate earlier, take off impeller, motor support constitution's installation is whole from the spiral case again, then pull down the impeller from the output of motor, pull down the motor from motor support on can. The utility model discloses a fan system is convenient for carry out the dismouting with fan and impeller under the air intake backward arranges the state.

Description

Fan system and range hood with same

Technical Field

The utility model relates to a for kitchen use household electrical appliances technical field specifically indicates a fan system and uses range hood that has this fan system.

Background

Range hood is the electrical apparatus that is essential in the kitchen at present, and is comparatively common and use more extensively to arrange oily smoke purification system in last.

At present, the upward-exhaust oil fume purification system is mainly divided into two types: a top-suction range hood and a near-suction range hood. The top-suction type range hood is more attractive, but the smoke inlet is higher, and the smoke suction effect is limited; compared with a top-suction range hood, the near-suction range hood has a lower smoke inlet, but is influenced by the appearance structure and the internal air duct structure of the near-suction range hood, and the existing near-suction range hood cannot better approach oil smoke, so that the oil smoke suction effect is limited to a great extent.

The fan system structure in the existing range hood is generally as shown in the invention patent application with publication number CN108087336A, namely, range hood with the centrifugal fan (application number: CN201710629367.3), and the fan system comprises a volute, an impeller, a motor support and a motor, wherein the impeller is rotatably arranged in the volute, the motor support is directly welded on a rear plate of the volute, and the motor is fixed on the volute through the motor support and the output end of the motor is connected with the impeller. When the fan system is maintained, the main maintenance parts are the motor and the impeller, namely the motor and the impeller are required to be detached under the installation state of the range hood. Because this type of fan system is under the user state, the air intake of fan is arranged forward, consequently, for easy dismounting, impeller and motor all take out from the air intake department of fan, fix the spiral case on range hood promptly and do not dismantle, and take out impeller, motor from air intake department in proper order. The motor bracket welded on the volute rear plate provides convenience for the motor to be installed from front to back, but simultaneously, the motor bracket also blocks the space at the rear side of the volute and does not allow the impeller and the motor to be taken out from the rear side of the volute.

When the fan system is reversely installed in the range hood, that is, the air inlet of the fan is arranged backwards, the existing fan system structure can not take out the fan and the impeller without disassembling the volute, and the whole fan system including the volute needs to be disassembled to further take out the impeller and the motor, which is very inconvenient.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the first technical problem that will solve is to prior art's current situation, provides a fan system convenient to with impeller and motor from spiral case rear side dismouting.

The utility model aims to solve the second technical problem to provide a use range hood that has above-mentioned fan system to the current situation of prior art, should have range hood and be convenient for carry out the dismouting, the later maintenance and the maintenance of being convenient for to the impeller and the motor of fan system.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: the utility model provides a fan system, includes spiral case, impeller, motor and motor support, the impeller can be located in the spiral case with rotating, the motor passes through the motor support and installs on the spiral case and power take off end is connected with the impeller, the spiral case has front bezel and the back plate of interval arrangement around, it has air intake, its characterized in that to open on the front bezel: the back plate is provided with a first mounting opening through which the impeller can pass, the motor support is shaped like a disc and is detachably arranged at the first mounting opening, and the motor is detachably arranged on the motor support.

Preferably, a positioning structure which is arranged close to the first mounting opening and can pre-position the first mounting opening in a motor bracket mounting state is arranged on the volute rear plate. Because the utility model discloses a motor support takes shape to discoid, when the motor support that will install motor, impeller is fixed with the spiral case, hardly fixes a position fast, and adopts above-mentioned location structure, then can realize motor support's location, labour saving and time saving fast.

Preferably, the positioning structure is a slot which is arranged near the lower edge of the first mounting opening and can be used for inserting the lower edge of the motor bracket.

As a preferable scheme, a positioning opening which is through from front to back is formed in the volute casing rear plate, correspondingly, an elastic clamping jaw which can be inserted into the positioning opening is arranged on the rear side wall of the motor support, and the elastic clamping jaw and the positioning opening jointly form the positioning structure.

Preferably, the volute casing rear plate is provided with a socket arranged close to the side edge of the first mounting opening, correspondingly, the rear wall of the motor support is provided with an insertion piece capable of being inserted downwards into the socket, and the insertion piece and the socket together form the positioning structure. Preferably, the width of the socket is gradually increased from bottom to top, and the inserting sheet is formed by folding the part, close to the edge, of the motor support backwards.

In each scheme, the outer diameter of the motor support is larger than the diameter of the first mounting opening, and the edge of the motor support is connected to the volute rear plate through a bolt. After the positioning structure is adopted, the using amount of bolts can be saved when the motor support is in threaded connection with the volute, and the installation time is saved.

In each of the above schemes, a second mounting opening is formed in the middle of the motor bracket, and the motor is arranged through the second mounting opening and connected to the motor bracket.

Preferably, the peripheral wall of the motor is provided with a radially extending assembling ring, the outer diameter of the assembling ring is larger than the diameter of the second mounting opening, and the assembling ring is connected to the motor support at the outer edge of the second mounting opening through a bolt. The fan system with the structure is a single-air-suction-port fan system, so that the assembly is convenient, the rear wall of the volute is arranged in a closed manner through the assembly of the assembly ring and the edge of the second mounting port, the air quantity loss is avoided, and the oil smoke suction effect is improved.

Preferably, the outer diameter of the motor is smaller than the diameter of the second mounting opening, a mounting frame protruding into the volute is arranged in the second mounting opening, an air inlet area for air to enter the volute is formed between the mounting frame and the edge of the second mounting opening, and the motor is arranged on the mounting frame. The structure is suitable for the fan with double air suction ports, and the structure is adopted for driving the two impellers to rotate by the motor.

Specifically, the mounting frame comprises a first assembling strip and a second assembling strip which are arranged at intervals and the end parts of which are respectively connected to the motor support, the middle parts of the first assembling strip and the second assembling strip respectively protrude inwards the volute to form protruding parts, and the motor is installed between the protruding parts of the first assembling strip and the protruding parts of the second assembling strip. Or the mounting frame is provided with an annular body, two sides of the annular body are respectively provided with a side plate extending forwards, the front end of the side plate is connected with the edge of the second mounting opening, and the motor is arranged on the annular body; the side plate is provided with an opening for air to pass through.

The utility model provides an use range hood that has above-mentioned fan system, includes the casing, its characterized in that: the fan system is arranged in the shell, the lower portion of the shell is provided with a vertically-arranged smoke inlet cavity, a smoke inlet communicated with the smoke inlet cavity is formed in the front side wall of the lower portion of the shell, the upper portion of the shell is provided with a smoke collecting cavity communicated with the smoke inlet cavity, the smoke collecting cavity extends forwards to form a mounting cavity used for mounting the fan system, an air inlet of the fan system is communicated with the smoke collecting cavity, and an air outlet of the fan system is arranged upwards.

Preferably, a first bottom plate connected with the rear plate extends forwards from the lower edge of the front plate, and the first bottom plate gradually inclines upwards from back to front. The structure is convenient for leading oil drops in the fan to the rear edge of the first bottom plate along the first bottom plate, and the rear edge is arranged corresponding to the outlet of the smoke inlet cavity, so that the oil drops on the fan are conveniently discharged downwards.

Preferably, the lower edge of the rear plate extends backwards to form a second bottom plate, the lower edge of the second bottom plate is connected with the outlet of the smoke inlet cavity, and a gap is formed between the second bottom plate and the first bottom plate. Furthermore, the second bottom plate gradually inclines upwards from back to front so as to form a flow guide structure capable of guiding oil dropping from the volute casing to the smoke inlet cavity. The structure is favorable for further discharging oil drops on the fan.

Preferably, the rear edge of the second bottom plate is inclined from top to bottom and gradually inclines backwards to form an inclined plate, and a guide air duct located between the smoke inlet cavity and the smoke collection cavity is formed between the inclined plate and the rear wall of the shell. This structure is convenient for on the one hand drip on the fan downwards discharge, and on the other hand, the guide air duct that the width enlarges gradually from bottom to top in front and back direction can make the oil smoke circulation that gets into the collection cigarette chamber steady, improves the oil absorption cigarette effect.

In each of the above schemes, the lower portion of the housing has a front side plate and a rear side plate which are arranged at a front-rear interval, the smoke inlet cavity is located between the front side plate and the rear side plate, the smoke inlet is opened at the lower portion of the front side plate, and the lower edge of the front side plate is higher than the lower edge of the rear side plate and is arranged to form the smoke inlet.

Compared with the prior art, the utility model has the advantages of: when the fan system of the utility model is installed, the motor is installed on the motor support, then the impeller is connected with the output end of the motor, so that the impeller, the motor and the motor support form an installation whole, and finally, the impeller is inserted into the volute from the first installation port on the rear plate of the volute, so that the motor support is corresponding to the first installation port and is fixed; when the motor support is detached, the motor support is detached from the volute rear plate, the whole installation body formed by the impeller, the motor and the motor support is detached from the volute, the impeller is detached from the output end of the motor, and the motor is detached from the motor support. The utility model discloses a fan system is convenient for carry out the dismouting with fan and impeller under the air intake backward arranges the state.

Drawings

Fig. 1 is a schematic structural diagram of a fan system according to embodiment 1 of the present invention;

FIG. 2 is a schematic view of the structure of FIG. 1 from another angle;

FIG. 3 is a partially exploded view of FIG. 1;

FIG. 4 is an exploded view of FIG. 1;

fig. 5 is a schematic view of an assembly structure of a motor bracket and a rear plate in embodiment 1 of the present invention;

FIG. 6 is a schematic view of the positioning structure of FIG. 5;

fig. 7 is a schematic view of an assembly structure of a motor bracket and a rear plate in embodiment 2 of the present invention;

FIG. 8 is a schematic view of the positioning structure of FIG. 7;

fig. 9 is a schematic view of an assembly structure of a motor bracket and a rear plate in embodiment 3 of the present invention;

FIG. 10 is a schematic view of the positioning structure of FIG. 9;

fig. 11 is a schematic structural diagram of a fan system in embodiment 4 of the present invention;

FIG. 12 is a schematic view of an assembly structure of the motor and the motor bracket in FIG. 11;

fig. 13 is a schematic structural diagram of a fan system in embodiment 5 of the present invention;

fig. 14 is a sectional view of the range hood in embodiment 1 of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

As shown in fig. 1 to 6 and 14, the fan system a of this embodiment includes a volute 1, an impeller 2, a motor 3, and a motor support 4, the impeller 2 is rotatably disposed in the volute 1, the motor 3 is mounted on the volute 1 through the motor support 4, and a power output end of the motor is connected to the impeller 2, the volute 1 has a front plate 11, a rear plate 12, and a volute annular wall 13, the front plate 11 and the rear plate 12 are arranged at a front-rear interval, and the volute annular wall 13 is disposed between the front plate 11 and the rear plate 12 and encloses an inner cavity for mounting the impeller 2 together with the front plate 11 and the rear plate 12. The front plate 11 is provided with an air inlet 111, and the top of the volute 1 is provided with an air outlet 14.

In this embodiment, the back plate 12 is provided with a first mounting opening 121 through which the impeller 2 can pass, the motor bracket 4 is shaped like a disc and detachably disposed at the first mounting opening 121, and the motor 3 is detachably disposed on the motor bracket 4. The back plate 12 of the volute 1 is provided with a positioning structure 15 which is arranged close to the first mounting opening 121 and can pre-position the first mounting opening in the mounting state of the motor bracket 4. Because the motor support 4 of this embodiment takes the shape of discoid, when motor support 4 that will have installed motor 3, impeller 2 is fixed with spiral case 1, hardly fixes a position fast, and adopts above-mentioned location structure 15, then can realize motor support 4's location, labour saving and time saving fast. The positioning structure 15 of the present embodiment is a slot disposed near the lower edge of the first mounting opening 121 and capable of inserting the lower edge of the motor bracket 4 therein.

In this embodiment, the outer diameter of the motor bracket 4 is larger than the diameter of the first mounting opening 121, and the edge of the motor bracket 4 is connected to the volute casing rear plate 12 by the bolt 16. Specifically, during installation, the lower edge of the motor bracket 4 is inserted into the slot for prepositioning, and then the motor bracket 4 and the rear plate 12 are fixed by bolts. The positioning structure 15 can save the use amount of the bolts 16 and save the installation time. The middle part of the motor support 4 is provided with a second mounting opening 41, the motor 3 is arranged through the second mounting opening 41, the outer peripheral wall of the motor 3 is provided with an assembling ring 31 extending along the radial direction, the outer diameter of the assembling ring 31 is larger than the diameter of the second mounting opening 41, and the assembling ring 31 is connected to the motor support 4 at the outer edge of the second mounting opening 41 through bolts. The fan system with the structure is a single-air-suction-port fan system, so that the assembly is convenient, the rear wall of the volute 1 is arranged in a closed manner through the assembly of the assembly ring 31 and the edge of the second mounting port 41, the air volume loss is avoided, and the oil smoke suction effect is improved.

The method for disassembling and assembling the fan system a in the embodiment comprises the following steps:

(1) during installation, the motor 3 is installed on the motor support 4, then the impeller 2 is connected with the output end of the motor 3, so that the impeller 2, the motor 3 and the motor support 4 form an installation whole, and finally, the impeller 2 is inserted into the volute 1 from the first installation opening 121 on the rear plate 12 of the volute 1, so that the motor support 4 is fixed at the first installation opening 121;

(2) when the motor support 4 is detached from the rear plate 12 of the volute 1, the whole installation body formed by the impeller 2, the motor 3 and the motor support 4 is detached from the volute 1, the impeller 2 is detached from the output end of the motor 3, and the motor 3 is detached from the motor support 4.

The range hood applied with the fan system a in the embodiment includes a housing 5, the housing 5 is internally provided with the fan system a, the lower portion of the housing 5 is provided with a vertically arranged smoke inlet cavity 51, the front side wall of the lower portion of the housing 5 is provided with a smoke inlet 511 communicated with the smoke inlet cavity 51, the upper portion of the housing 5 is provided with a smoke collection cavity 52 communicated with the smoke inlet cavity 51, the smoke collection cavity 52 extends forwards to form an installation cavity 53 for installing the fan system a, an air inlet 111 of the fan system a is arranged towards the smoke collection cavity 52, and an air outlet 14 of the fan system a is arranged upwards.

The lower edge of the front plate 11 is extended forward to form a first bottom plate 112 connected to the rear plate 12, and the first bottom plate 112 is gradually inclined upward from the rear to the front. This configuration facilitates the guiding of the oil droplets in the fan along the first bottom plate 112 to the rear edge of the first bottom plate 112, which is disposed corresponding to the outlet of the smoke inlet chamber 51, and facilitates the downward discharge of the oil droplets in the fan. The lower edge of the rear plate 12 extends rearward to form a second bottom plate 122, the lower edge of the second bottom plate 122 is connected with the outlet of the smoke inlet chamber 51, and a gap 120 is formed between the second bottom plate 122 and the first bottom plate 112. The second bottom plate 122 is inclined upward from the rear to the front so as to form a flow guiding structure capable of guiding the oil dropping from the scroll case 1 to the smoke inlet chamber 51, which is advantageous for further discharging the oil dropping from the fan. The rear edge of the second bottom plate 122 gradually inclines backward from top to bottom to form an inclined plate 125, a guide air duct 54 between the smoke inlet chamber 51 and the smoke collection chamber 52 is formed between the inclined plate 125 and the rear wall of the housing 5, which is convenient for discharging oil drops on the fan downward, and on the other hand, the guide air duct 54 with gradually enlarged width from bottom to top in the front-rear direction can make the oil smoke entering the smoke collection chamber 52 circulate smoothly, thereby improving the effect of absorbing oil smoke.

The lower part of the housing 5 has a front side plate 55 and a rear side plate 56 which are arranged at a distance from each other, the smoke inlet chamber 51 is located between the front side plate 55 and the rear side plate 56, and the lower edge of the front side plate 55 is arranged higher than the lower edge of the rear side plate 56 to form a smoke inlet 511.

Example 2:

this example differs from example 1 in that: the positioning structure in this embodiment is different from that in embodiment 1.

Specifically, as shown in fig. 7 and 8, the rear plate 12 of the volute 1 is provided with a positioning opening 123 penetrating in the front-rear direction, and correspondingly, the rear side wall of the motor bracket 4 is provided with an elastic claw 42 capable of being inserted into the positioning opening 123, and the elastic claw 42 and the positioning opening 123 together form the positioning structure of the embodiment.

Example 3:

Specifically, as shown in fig. 9 and 10, the rear plate 12 of the volute 1 is provided with a socket 124 disposed near the side edge of the first mounting opening 121, and correspondingly, the rear wall of the motor bracket 4 is provided with a tab 43 capable of being downwardly inserted into the socket 124, and the tab 43 and the socket 124 together form the positioning structure of the embodiment. The width of the inserting opening 124 is gradually increased from bottom to top, and the inserting piece 43 is formed by folding the part of the motor bracket 4 close to the edge backwards.

Example 4:

this example differs from example 1 in that: the motor holder in this embodiment is different from embodiment 1.

The outer diameter of the motor 3 of this embodiment is smaller than the diameter of the second mounting opening 41 ', a mounting bracket 411 protruding into the scroll casing 1 is disposed in the second mounting opening 41 ', an air inlet area 412 for air to enter the scroll casing 1 is formed between the mounting bracket 411 and the edge of the second mounting opening 41 ', and the motor 3 is disposed on the mounting bracket 411. The structure is suitable for the fan with double air suction ports, and the structure is adopted for driving the two impellers to rotate by the motor 3.

Specifically, as shown in fig. 13, the mounting bracket 411 includes a first mounting bar 4113 and a second mounting bar 4114 which are arranged at intervals and have end portions connected to the motor bracket 4, the middle portions of the first mounting bar 4113 and the second mounting bar 4114 protrude into the scroll casing 1 to form a protruding portion 4110, and the motor 3 is mounted between the protruding portion 4110 of the first mounting bar 4113 and the protruding portion 4110 of the second mounting bar 4114.

Example 5:

this example differs from example 4 in that: the mounting frame in this embodiment is different from embodiment 4.

As shown in fig. 11 and 12, the mounting bracket 411 'of the present embodiment has a ring-shaped body 4111, two sides of the ring-shaped body 4111 respectively have a side plate 4112 extending forward, a front end of the side plate 4112 is connected to an edge of the second mounting opening 41', the motor 3 is disposed on the ring-shaped body 4111, and an opening 4115 for passing air is opened on the side plate 4112. The annular body 4111 is located at the front side of the motor bracket 4 ', and an air inlet area 412 ' is formed between the edge of the annular body 4111 and the edge of the second mounting opening 41 '.

Claims

1. The utility model provides a fan system, includes spiral case (1), impeller (2), motor (3) and motor support (4), impeller (2) can be located spiral case (1) with rotating, motor (3) are installed on spiral case (1) and power take off end is connected with impeller (2) through motor support (4), spiral case (1) have front bezel (11) and back plate (12) that the interval was arranged around having, it has air intake (111), its characterized in that to open on front bezel (11): the rear plate (12) is provided with a first mounting opening (121) through which the impeller (2) can pass, the motor support (4) is shaped like a disc and detachably arranged at the first mounting opening (121), and the motor (3) is detachably arranged on the motor support (4).

2. The fan system of claim 1, wherein: and a positioning structure (15) which is arranged close to the first mounting opening (121) and can pre-position the first mounting opening in the mounting state of the motor support (4) is arranged on the rear plate (12) of the volute (1).

3. The fan system of claim 2, wherein: the positioning structure (15) is a slot which is arranged close to the lower edge of the first mounting opening (121) and can be used for inserting the lower edge of the motor support (4).

4. The fan system of claim 2, wherein: the volute casing (1) is characterized in that a positioning opening (123) which is through from front to back is formed in a rear plate (12), correspondingly, an elastic claw (42) which can be inserted into the positioning opening (123) is arranged on the rear side wall of the motor support (4), and the elastic claw (42) and the positioning opening (123) jointly form the positioning structure.

5. The fan system of claim 2, wherein: a socket (124) arranged close to the side edge of the first mounting opening (121) is formed in the rear plate (12) of the volute (1), correspondingly, an inserting piece (43) capable of being inserted into the socket (124) downwards is arranged on the rear wall of the motor support (4), and the inserting piece (43) and the socket (124) jointly form the positioning structure.

6. The fan system of claim 5, wherein: the width of socket (124) increases gradually from bottom to top, inserted sheet (43) form by motor support (4) are close to the local complete book backward of edge.

7. The fan system of any of claims 1-6, wherein: the outer diameter of the motor support (4) is larger than the diameter of the first mounting opening (121), and the edge of the motor support (4) is connected to the rear plate (12) of the volute (1) through a bolt (16).

8. The fan system of any of claims 1-6, wherein: the middle part of the motor support (4) is provided with a second mounting opening (41), and the motor (3) penetrates through the second mounting opening (41) to be arranged and connected on the motor support (4).

9. The fan system of claim 8, wherein: be provided with on the periphery wall of motor (3) along radial extension assembly circle (31), the external diameter of assembly circle (31) is greater than the diameter of second installing port (41), assembly circle (31) pass through bolted connection on motor support (4) of second installing port (41) outer fringe.

10. The fan system of claim 8, wherein: the outer diameter of the motor (3) is smaller than the diameter of the second mounting opening (41 '), a mounting frame (411) protruding into the volute (1) is arranged in the second mounting opening (41 '), an air inlet area (412) for air to enter the volute (1) is formed between the edge of the mounting frame (411) and the edge of the second mounting opening (41 '), and the motor (3) is arranged on the mounting frame (411).

11. The fan system of claim 10, wherein: mounting bracket (411) are including interval arrangement and tip connect respectively in first assembly strip (4113), second assembly strip (4114) on motor support (4), the middle part of first assembly strip (4113), second assembly strip (4114) is protruding formation protrusion position (4110) respectively in to spiral case (1), install between protrusion position (4110) of first assembly strip (4113) and protrusion position (4110) of second assembly strip (4114) motor (3).

12. The fan system of claim 10, wherein: the mounting bracket has ring body (4111), and the both sides of this ring body (4111) have curb plate (4112) that extend forward respectively, the front end of this curb plate (4112) with the edge of second installing port (41') is connected, motor (3) are located on ring body (4111).

13. The fan system of claim 12, wherein: an opening (4115) through which air passes is formed in the side plate (4112).

14. A range hood using the fan system of any one of claims 1 to 13, comprising a housing (5), wherein: be equipped with in casing (5) fan system (a), casing (5) lower part has vertical smoke inlet chamber (51) of arranging, it has smoke inlet (511) that are linked together with this smoke inlet chamber (51) to open on the preceding lateral wall of casing (5) lower part, casing (5) upper portion has collection smoke chamber (52) that are linked together with smoke inlet chamber (51), collection smoke chamber (52) extend forward and form installation cavity (53) that are used for installing fan system (a), air intake (111) and collection smoke chamber (52) of fan system (a) are linked together, air outlet (14) of fan system (a) arrange up.

15. The range hood of claim 14, wherein: the lower edge of the front plate (11) extends forwards to form a first bottom plate (112) connected with the rear plate (12), and the first bottom plate (112) inclines upwards gradually from back to front.

16. The range hood of claim 15, wherein: the lower edge of the rear plate (12) extends backwards to form a second bottom plate (122), the lower edge of the second bottom plate (122) is connected with the outlet of the smoke inlet cavity (51), and a gap (120) is formed between the second bottom plate (122) and the first bottom plate (112).

17. The range hood of claim 16, wherein: the second bottom plate (122) is gradually inclined upwards from back to front so as to form a flow guide structure capable of guiding oil dropping from the volute (1) to the smoke inlet cavity (51).

18. The range hood of claim 16, wherein: the rear edge of the second bottom plate (122) is gradually inclined backwards from top to bottom to form an inclined plate (125), and a guide air duct (54) positioned between the smoke inlet cavity (51) and the smoke collection cavity (52) is formed between the inclined plate (125) and the rear wall of the shell (5).

19. The range hood of any one of claims 14 to 18, wherein: the lower part of the shell (5) is provided with a front side plate (55) and a rear side plate (56) which are arranged at intervals in the front-rear direction, the smoke inlet cavity (51) is positioned between the front side plate (55) and the rear side plate (56), and the lower edge of the front side plate (55) is higher than the lower edge of the rear side plate (56) and is arranged so as to form a smoke inlet (511).