OVEN LID OF LARGE-CAPACITY AIR OVEN

The present invention discloses an oven lid of a large-capacity air oven. The key point of the technical solution of the present invention is that the oven lid of the large-capacity air oven includes a casing, a middle casing is arranged inside the casing, and an inner casing is fixedly connected to the bottom of the middle casing; a DC brushless motor is employed, and due to the fact that the size of the DC brushless motor is small, which allows the space between the inner casing and the middle casing to be compressed, thereby expanding the volume of an inner oven body and making the space of the air oven larger; and in addition, a first recess, a second recess and a third recess are provided, so that structures among the middle casing, the inner casing, an exhaust fan and a circulation fan are more compact.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to Application No. 202222042359.8, filed in the Chinese Patent Office on Aug. 4, 2022, which is expressly incorporated herein in its entirety by reference thereto.

TECHNICAL FIELD

The present invention relates to the field of air ovens, and in particular, to an oven lid of a large-capacity air oven.

BACKGROUND ART

At the present stage, in the family kitchen, there is often an air oven, and the air oven uses hot air circulation in the oven to cook food; a fan assembly is arranged on an oven lid of the air oven, and includes a motor, an exhaust fan and a circulation fan which are connected to the motor, and the like; and the motor drives the exhaust fan and the circulation fan to rotate so as to realize functions such as hot air circulation.

In the prior art, a shade-pole motor is often employed as the motor; and due to the larger size of the shaded-pole motor, it occupies a large space, resulting in a larger appearance and less compact structure of the oven lid.

SUMMARY OF THE INVENTION

In view of the shortcomings of the prior art, the purpose of the present invention is to provide an oven lid of a large-capacity air oven, which is used for reducing the space occupied by the motor on the oven lid.

In order to achieve the above purpose, the present invention provides the following technical solution: an oven lid of a large-capacity air oven includes a casing, where a middle casing is arranged inside the casing, an inner casing is fixedly connected to the bottom of the middle casing, a heat dissipation cavity is formed between the middle casing and the inner casing, and a central hole communicated with the heat dissipation cavity is provided on the middle casing; a DC brushless motor is fixedly connected to the middle casing, and an interstice is provided between the DC brushless motor and the central hole; an output shaft of the DC brushless motor is fixedly connected to an exhaust fan and a circulation fan, the circulation fan is located under the inner casing, and the exhaust fan is located inside the heat dissipation cavity; and an exhaust component is communicated with one side of the middle casing, and an air outlet is provided on the exhaust component.

As a further improvement of the present invention, a plurality of supports are arranged along the outer side surface of the DC brushless motor in an integrated molding manner, and the supports are fixedly connected to the middle casing.

As a further improvement of the present invention, there are three supports, the three supports are evenly distributed along the circumferential direction of the output shaft of the DC brushless motor.

As a further improvement of the present invention, a plurality of positioning slots corresponding to the supports are provided on the upper surface of the middle casing.

As a further improvement of the present invention, a first recess is formed on the exhaust fan, and at least portion of the DC brushless motor enters the first recess.

As a further improvement of the present invention, a second recess is formed on the inner casing, and at least portion of the first recess enters the second recess.

As a further improvement of the present invention, a third recess is formed on the circulation fan, and at least portion of the second recess enters the third recess.

As a further improvement of the present invention, a through hole is provided on the inner casing, an exhaust hole is provided on the middle casing, and the exhaust hole corresponds to the through hole and is communicated with the exhaust component.

As a further improvement of the present invention, the first recess includes a first recess bottom surface and a first circular truncated cone side surface, and the slope of the first circular truncated cone side surface is A1, with A1being 30 degrees;

the second recess includes a second recess bottom surface and a second circular truncated cone side surface, and the slope of the second circular truncated cone side surface is A2, with A2being 30 degrees; and

the third recess includes a third recess bottom surface and a third circular truncated cone side surface, and the slope of the third circular truncated cone side surface is A3, with A3being 30 degrees.

As a further improvement of the present invention, the exhaust fan includes the first recess and a plurality of first fan blades arranged outside the first recess in a surrounding manner; the circulation fan includes the third recess and a plurality of second fan blades arranged outside the third recess in a surrounding manner;

each of the first fan blades includes a first fan plate and a first positioning plate which are connected to each other, the cross section of the fan blade formed by connecting the first fan plate and the first positioning plate is L-shaped, the included angle between the first fan plate and the first positioning plate is D1, with D1being 90 degrees, and the first fan plate extends in the direction opposite to the forming direction of the first recess; and

each of the second fan blades includes a second fan plate and a second positioning plate which are connected to each other, the cross section of the fan blade formed by connecting the second fan plate and the second positioning plate is L-shaped, the included angle between the second fan plate and the second positioning plate is D3, with D3being 90 degrees, and the second fan plate extends towards the recess direction in which the third recess is formed.

As a further improvement of the present invention, each of the first fan blades includes a first positioning plate reinforcement portion, and the first positioning plate reinforcement portion is arranged on the surface of the first positioning plate and protrudes in a direction opposite to the forming direction of the first recess.

As a further improvement of the present invention, each of the first positioning plates is approximately a right-angled triangle, and includes a first base portion, a first straight edge, a first top boundary and a first hypotenuse which are connected in sequence, where the first positioning plate is connected to the first recess by means of the first base portion, the first straight edge extends radially through a center of the circle of the first recess, the first hypotenuse is connected to the first fan plate, the height of the inner casing away from the bottom edge of the first fan plate is B1, with B1being 4 mm, and the height from the bottom edge of the first fan plate to the top edge thereof is B2, with B2being 9.4 mm; and

as a further improvement of the present invention, the exhaust fan includes the ten first fan blades evenly surrounding the edge of the first recess, and the included angle formed between the first straight edge of each first positioning plate and the first hypotenuse of the adjacent first positioning plate is D2, with D2being 51 degrees.

As a further improvement of the present invention, the first positioning plates are evenly distributed around the first recess, and an interstice is formed between the every two adjacent first positioning plates; first fan blade chamfered mouths are formed by the interstices, and each of the first fan blade chamfered mouths includes a first fan blade main transition arc and a first fan blade auxiliary transition arc, where the first fan blade main transition arc is used for connecting the first hypotenuse and the first base portion, the first fan blade auxiliary transition arc is used for connecting the first straight edge and the first base portion, and the bending directions of the first fan blade main transition arc and the first fan blade auxiliary transition arc are opposite to each other.

As a further improvement of the present invention, each of the second fan blades includes a second positioning plate reinforcement portion, and the second positioning plate reinforcement portion is arranged on the surface of the second positioning plate and protrudes towards the recess direction in which the third recess is formed.

As a further improvement of the present invention, each of the second positioning plates is approximately a right-angled triangle, and includes a second base portion, a second straight edge, a second top boundary and a second hypotenuse which are connected in sequence, where the second positioning plate is connected to the third recess by means of the second base portion, the second straight edge extends radially through a center of the circle of the third recess, the second hypotenuse is connected to the second fan plate, the height of the inner casing away from the bottom edge of the second fan plate is B3, with B3being 3.6 mm, and the height from the bottom edge of the second fan plate to the top edge thereof is B4, with B4being 13.5 mm; and

as a further improvement of the present invention, the circulation fan includes the ten second fan blades evenly surrounding the edge of the third recess, and the included angle formed between the second straight edge of each second positioning plate and the second hypotenuse of the adjacent second positioning plate is D4, with D4being 53 degrees.

As a further improvement of the present invention, the second positioning plates are evenly distributed around the third recess, and an interstice is formed between the every two adjacent second positioning plates; second fan blade chamfered mouths are formed by the interstices, and each of the second fan blade chamfered mouths includes a second fan blade main transition arc and a second fan blade auxiliary transition arc, where the second fan blade main transition arc is used for connecting the second hypotenuse and the second base portion, the second fan blade auxiliary transition arc is used for connecting the second straight edge and the second base portion, and the bending directions of the second fan blade main transition arc and the second fan blade auxiliary transition arc are opposite to each other.

As a further improvement of the present invention, the exhaust component extends towards the outer side of the middle casing, the air outlet is provided on the exhaust component, and the shape of the air outlet is grid-shaped; the middle casing includes a middle casing bottom plate extending along a plane, and a middle casing side wall extending from the middle casing bottom plate towards one side; the middle casing side wall is provided with the exhaust hole; the exhaust component includes an exhaust component top surface and an exhaust component bottom surface which are arranged in sequence along the direction from the middle casing bottom plate to the middle casing side wall; the exhaust component bottom surface includes a planar bottom wall and an arc-shaped bottom wall that are connected in sequence; and the air outlet is provided at the side of the exhaust component top surface close to the arc-shaped bottom wall.

As a further improvement of the present invention, the middle casing is formed by two-stage upward draft, so that a step-like middle casing stair-shaped surface is formed at the waist of the middle casing; the draft slope of the first stage of the middle casing is C1, with C1being 15 degrees; the draft slope of the second stage of the middle casing is C2, with C2being 15 degrees; and the inner casing has a circular inclined plane, the slope of the inclined plane is C3, with C3being 30 degrees.

As a further improvement of the present invention, the exhaust component is provided with a plurality of reinforcing ribs.

As a further improvement of the present invention, the first recess includes a first crisscross recess, and the first crisscross recess is formed by means of draft towards the recess direction of the first recess; and the third recess includes a second crisscross recess, and the second crisscross recess is formed by means of draft in the direction opposite to the recess direction of the third recess.

As a further improvement of the present invention, the first recess is formed on the exhaust fan, and at least portion of the DC brushless motor enters the first recess; and

the second recess is formed on the inner casing, and at least portion of the first recess enters the second recess.

The third recess is formed on the circulation fan, and at least portion of the second recess enters the third recess; and

the plurality of supports are arranged along the outer side surface of the DC brushless motor in an integrated molding manner, and the supports are fixedly connected to the inner casing.

As a further improvement of the present invention, the first recess is matched with the outer wall of the DC brushless motor.

In order to achieve the above purpose, the present invention provides another technical solution: an oven lid of a large-capacity air oven includes an inner casing, where a DC brushless motor is fixedly connected to the inner casing, an output shaft of the DC brushless motor is connected to an exhaust fan and a circulation fan, the exhaust fan is located above the inner casing, and the circulation fan is located under the inner casing; a first recess is formed on the exhaust fan, and at least portion of the DC brushless motor enters the first recess;

a second recess is formed on the inner casing, and at least portion of the first recess enters the second recess; and

a third recess is formed on the circulation fan, and at least portion of the second recess enters the third recess.

The present invention has the beneficial effects that: the DC brushless motor is employed, and due to the fact that the size of the DC brushless motor is small, the space occupied by the DC brushless motor is small, which allows the space between the inner casing and the middle casing to be compressed, thereby expanding the volume of an inner oven body and making the space of the air oven larger; and in addition, the first recess, the second recess and the third recess are provided, so that structures among the middle casing, the inner casing, the exhaust fan and the circulation fan are more compact, and interstices between the inner casing and the middle casing and between the circulation fan and the inner casing are further reduced.

The reference numerals on the drawings are described below:1denotes a middle casing;11denotes a central hole;12denotes positioning slots;13denotes an exhaust hole;14denotes a middle casing bottom plate;15denotes a middle casing side wall;16denotes a middle casing stair-shaped surface;2denotes an inner casing;21denotes a second recess;211denotes a second recess bottom surface;212denotes a second circular truncated cone side surface;22denotes a through hole;3denotes a heat dissipation cavity;4denotes a DC brushless motor;41denotes an exhaust fan;411denotes a first recess;4111denotes a first recess bottom surface;4112denotes a first circular truncated cone side surface;4113denotes a first crisscross recess;412denotes first fan blades;4121denotes first fan plates;41221denotes first base portions;41222denotes first straight edges;41223denotes first top boundaries;41224denotes first hypotenuses;4122denotes first positioning plates;4123denotes first positioning plate reinforcement portions;4124denotes first fan blade chamfered mouths;41241denotes first fan blade main transition arcs;41242denotes first fan blade auxiliary transition arcs;42denotes a circulation fan;421denotes a third recess;4211denotes a third recess bottom surface;4212denotes a third circular truncated cone side surface;4213denotes a second crisscross recess;422denotes second fan blades;4221denotes second fan plates;4222denotes second positioning plates;4223denotes second positioning plate reinforcement portions;4224denotes second fan blade chamfered mouths;42241denotes second fan blade main transition arcs;42242denotes second fan blade auxiliary transition arcs;43denotes supports;5denotes an exhaust component;51denotes an air outlet;52denotes an exhaust component top surface;53denotes an exhaust component bottom surface;531denotes a planar bottom wall; and532denotes an arc-shaped bottom wall.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The same components are denoted by the same reference numerals on the drawings. It should be noted that the terms “front”, “rear”, “left”, “right”, “upper” and “lower” used in the following description refer to directions in the drawings, and the terms “bottom surface” and “top surface” as well as “inner” and “outer” refer to directions toward and away from the geometric center of a particular component, respectively.

Embodiment I

Referring toFIG.1toFIG.6, an oven lid of a large-capacity air oven provided by the embodiment includes a casing (not shown in the figure) and a fan assembly; the air oven includes an outer oven body and an inner oven body, and a cavity is formed between the outer oven body and the inner oven body; a middle casing1is arranged inside the casing, and an inner casing2is fixedly connected to the bottom of the middle casing1; a heat dissipation cavity3is formed between the middle casing1and the inner casing2, and a central hole11communicated with the heat dissipation cavity3is provided on the middle casing1; and a DC brushless motor4is fixedly connected to the middle casing1. Due to the facts that the DC brushless motor4is small in size and the axial dimension of the DC brushless motor is shorter than that of a shade-pole motor, the space occupied by the DC brushless motor is small, which allows the space between the inner casing2and the middle casing1to be compressed, thereby expanding the volume of the inner oven body, making the space of the air oven larger, enabling the structure between the middle casing1and the inner casing2to be more compact, and reducing the overall mass of the oven lid. An interstice is provided between the DC brushless motor4and the central hole11, the hot air in the cavity is drawn in by an exhaust fan41through the interstice and sent out by an exhaust component5, so as to maintain the temperature inside the outer oven body and prevent same from being overheated. An output shaft of the DC brushless motor4is fixedly connected to the exhaust fan41and a circulation fan42, the circulation fan42is located below the inner casing2and used for blowing the air towards food, and the hot air circulates inside the inner oven body. The exhaust fan41is located in the heat dissipation cavity3, one side of the middle casing1is communicated with the exhaust component5, and an air outlet51is provided on the exhaust component.

Referring toFIG.1andFIG.2, a plurality of supports43are arranged along the outer side surface of the DC brushless motor4in an integrated molding manner, and the supports43are fixedly connected to the middle casing1; the supports43are provided with fixing holes, and are fixedly connected to the middle casing1by means of standard components such as bolts and nuts; and a gasket is placed between each of the supports43and the middle casing1so as to prevent the support43from crushing the middle casing1during fixation.

There are three supports43, the three supports are evenly distributed along the circumferential direction of the output shaft of the DC brushless motor4, with a spacing angle of 120 degrees between the every two adjacent supports43. Due to the arrangement of the three supports43, the DC brushless motor4is enabled to be more stable.

Referring toFIG.3, a plurality of positioning slots12corresponding to the supports43are provided on the upper surface of the middle casing1. The positioning slots12are used for positioning the supports43; and after the installation position of the DC brushless motor4is determined, the installation is facilitated. The positioning slots12are provided with connecting holes corresponding to the fixing holes, and the bolts pass through the fixing holes and the connecting holes to fix the supports43and the middle casing1.

Referring toFIG.2,FIG.4,FIG.5andFIG.6, a first recess411is formed on the exhaust fan41, and at least portion of the DC brushless motor4enters the first recess411. The exhaust fan41includes a plurality of first fan blades and a first connecting body located at the central portion of the exhaust fan, where the first connecting body and the first fan blades are integrally formed, and the first recess411is formed on the first connecting body, which gives a space for partially accommodating the DC brushless motor4, so that the space occupied by the heat dissipation cavity3at the fan blade portion can be compressed, and the structure is more compact.

A second recess21is formed on the inner casing2, and at least portion of the first recess411enters the second recess21. The second recess21provides an accommodating space for the first recess411, and reduces the interstice between the inner casing2and the exhaust fan41, so that the structure between the inner casing2and the exhaust fan41is enabled to be more compact.

A third recess421is formed on the circulation fan42, and at least portion of the second recess21enters the third recess421. The circulation fan42includes a plurality of second fan blades and a second connecting body located at the central portion of the circulation fan, where the second connecting body and the second fan blades are integrally formed, and the third recess421is formed on the second connecting body, which gives an accommodating space for the second recess21, and allows the structure between the second fan blades and the inner casing2to be more compact, so that the space of the air oven is expanded.

A through hole22is provided on the inner casing2, an exhaust hole13is provided on the middle casing1, the exhaust hole13corresponds to the through hole22and is communicated with the exhaust component5, and the circulation air of a second fan may come from the through hole22.

As shown inFIG.7, the first recess411includes a first recess bottom surface4111and a first circular truncated cone side surface4112, and the slope of the first circular truncated cone side surface4112is A1, with A1being 30 degrees;

the second recess21includes a second recess bottom surface211and a second circular truncated cone side surface212, and the slope of the second circular truncated cone side surface212is A2, with A2being 30 degrees; and

the third recess421includes a third recess bottom surface4211and a third circular truncated cone side surface4212, and the slope of the third circular truncated cone side surface4212is A3, with A3being 30 degrees.

As shown inFIG.4andFIG.5, the exhaust fan41includes the first recess411and a plurality of first fan blades412arranged outside the first recess411in a surrounding manner; and the circulation fan42includes the third recess421and a plurality of second fan blades422arranged outside the third recess421in a surrounding manner.

Further, each of the first fan blades412includes a first fan plate4121and a first positioning plate4122which are connected to each other, the cross section of the fan blade formed by connecting the first fan plate and the first positioning plate is L-shaped, the included angle between the first fan plate4121and the first positioning plate4122is D1, with D1being 90 degrees, and the first fan plate4121extends in the direction opposite to the forming direction of the first recess411; and

each of the second fan blades422includes a second fan plate4221and a second positioning plate4222which are connected to each other, the cross section of the fan blade formed by connecting the second fan plate and the second positioning plate is L-shaped, the included angle between the second fan plate4221and the second positioning plate4222is D3, with D3being 90 degrees, and the second fan plate4221extends towards the recess direction in which the third recess421is formed.

As shown inFIG.4,FIG.8andFIG.9, each of the first fan blades412includes a first positioning plate reinforcement portion4123, and the first positioning plate reinforcement portion4123is arranged on the surface of the first positioning plate4122and protrudes in a direction opposite to the forming direction of the first recess411.

Further, each of the first positioning plates4122is approximately a right-angled triangle, and includes a first base portion41221, a first straight edge41222, a first top boundary41223and a first hypotenuse41224which are connected in sequence, where the first positioning plate4122is connected to the first recess411by means of the first base portion41221, the first straight edge41222extends radially through a center of the circle of the first recess411, the first hypotenuse41224is connected to the first fan plate4121, the height of the inner casing2away from the bottom edge of the first fan plate4121is B1, with B1being 4 mm, and the height from the bottom edge of the first fan plate to the top edge thereof is B2, with B2being 9.4 mm; and

the exhaust fan41includes the ten first fan blades412evenly surrounding the edge of the first recess411, and the included angle formed between the first straight edge of each first positioning plate4122and the first hypotenuse of the adjacent first positioning plate4122is D2, with D2being 51 degrees.

Still further, the first positioning plates4122are evenly distributed around the first recess411, and an interstice is formed between the every two adjacent first positioning plates4122; first fan blade chamfered mouths4124are formed by the interstices, and each of the first fan blade chamfered mouths4124includes a first fan blade main transition arc41241and a first fan blade auxiliary transition arc41242, where the first fan blade main transition arc41241is used for connecting the first hypotenuse41224and the first base portion41221, the first fan blade auxiliary transition arc41242is used for connecting the first straight edge41222and the first base portion41221, and the bending directions of the first fan blade main transition arc and the first fan blade auxiliary transition arc are opposite to each other.

As shown inFIG.5,FIG.8andFIG.10, each of the second fan blades422includes a second positioning plate reinforcement portion4223, and the second positioning plate reinforcement portion4223is arranged on the surface of the second positioning plate4222and protrudes towards the recess direction in which the third recess421is formed.

Further, each of the second positioning plates4222is approximately a right-angled triangle, and includes a second base portion42221, a second straight edge42222, a second top boundary42223and a second hypotenuse42224which are connected in sequence, where the second positioning plate4222is connected to the third recess421by means of the second base portion42221, the second straight edge42222extends radially through a center of the circle of the third recess421, the second hypotenuse42224is connected to the second fan plate4221, the height of the inner casing2away from the bottom edge of the second fan plate4221is B3, with B3being 3.6 mm, and the height from the bottom edge of the second fan plate to the top edge thereof is B4, with B4being 13.5 mm; and

the circulation fan42includes the ten second fan blades422evenly surrounding the edge of the third recess421, and the included angle formed between the second straight edge42222of each second positioning plate4222and the second hypotenuse42224of the adjacent second positioning plate4222is D4, with D4being 53 degrees.

Still further, the second positioning plates4222are evenly distributed around the third recess421, and an interstice is formed between the every two adjacent second positioning plates4222; second fan blade chamfered mouths4224are formed by the interstices, and each of the second fan blade chamfered mouths4224includes a second fan blade main transition arc42241and a second fan blade auxiliary transition arc42242, where the second fan blade main transition arc42241is used for connecting the second hypotenuse42224and the second base portion42221, the second fan blade auxiliary transition arc42242is used for connecting the second straight edge42222and the second base portion42221, and the bending directions of the second fan blade main transition arc and the second fan blade auxiliary transition arc are opposite to each other.

As shown inFIG.1, the exhaust component5is provided with a plurality of reinforcing ribs. The exhaust component5extends towards the outer side of the middle casing1, the air outlet51is provided on the exhaust component5, and the shape of the air outlet51is grid-shaped; the middle casing1includes a middle casing bottom plate14extending along a plane, and a middle casing side wall15extending from the middle casing bottom plate14towards one side; the middle casing side wall is provided with the exhaust hole13; the exhaust component5includes an exhaust component top surface52and an exhaust component bottom surface53which are arranged in sequence along the direction from the middle casing bottom plate14to the middle casing side wall15; the exhaust component bottom surface53includes a planar bottom wall531and an arc-shaped bottom wall532that are connected in sequence; and the air outlet51is provided at the side of the exhaust component top surface52close to the arc-shaped bottom wall532.

It is worth mentioning that the middle casing1is formed by two-stage upward draft, so that a step-like middle casing stair-shaped surface16is formed at the waist of the middle casing; the draft slope of the first stage of the middle casing1a is C1, with C1being 15 degrees; the draft slope of the second stage of the middle casing1is C2, with C2being 15 degrees; and the inner casing2has a circular inclined plane, the slope of the inclined plane is C3, with C3being 30 degrees.

It is more worth mentioning that the first recess411includes a first crisscross recess4113, and the first crisscross recess4113is formed by means of draft towards the recess direction of the first recess411; and the third recess421includes a second crisscross recess4213, and the second crisscross recess4213is formed by means of draft in the direction opposite to the recess direction of the third recess421.

Embodiment II

An oven lid of a large-capacity air oven provided by the embodiment is as shown inFIG.14, a first recess411is formed on an exhaust fan41, and at least portion of a DC brushless motor4enters the first recess411; and

a second recess21is formed on an inner casing2, and at least portion of the first recess411enters the second recess21.

A third recess421is formed on a circulation fan42, and at least portion of the second recess21enters the third recess421; and

a plurality of supports43are arranged along the outer side surface of the DC brushless motor4in an integrated molding manner, and the supports43are fixedly connected to the inner casing2.

In this embodiment, except that the portion of the DC brushless motor4is different from that of Embodiment 1, the rest portions are the same as those of Embodiment 1, which will not be repeated here.

Embodiment III

An oven lid of a large-capacity air oven provided by the embodiment is as shown inFIG.15, an exhaust fan41is fixedly connected to a DC brushless motor4. The exhaust fan41includes a first recess411and a plurality of first fan blades412arranged outside the first recess411in a surrounding manner; and the first recess411is matched with the outer wall of the DC brushless motor4.

In this embodiment, except that the portion of the exhaust fan41is different from that of Embodiment1, the rest portions are the same as those of Embodiment1, which will not be repeated here.

Embodiment IV

An oven lid of a large-capacity air oven provided by the embodiment includes a casing (not shown in the figure) and a fan assembly; and the air oven includes an outer oven body and an inner oven body, and a cavity is formed between the outer oven body and the inner oven body.

As shown inFIG.16andFIG.17, an inner casing2is arranged inside the casing, and the inner casing2is fixedly connected to a DC brushless motor4; an output shaft of the DC brushless motor4is connected to an exhaust fan41and a circulation fan42, the exhaust fan41is located above the inner casing2, and the circulation fan42is located under the inner casing2; a first recess411is formed on the exhaust fan41, and at least portion of the DC brushless motor4enters the first recess411; and

a second recess21is formed on the inner casing2, and at least portion of the first recess411enters the second recess21.

A third recess421is formed on the circulation fan42, and at least portion of the second recess21enters the third recess421.

It is worth mentioning that a plurality of supports43are arranged along the outer side surface of the DC brushless motor4in an integrated molding manner, the supports43are fixedly connected to the inner casing2, and the supports43are located under the exhaust fan41.

The rest portions of this embodiment are the same as those of Embodiment 1, which will not be repeated here.

The foregoing descriptions are merely exemplary implementations of the present invention, the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions under the idea of the present invention all belong to the protection scope of the present invention. It should be pointed out that for those ordinary persons skilled in the art, some improvements and embellishments without departing from the principle of the present invention shall also fall within the protection scope of the present invention.