CN112879352A

CN112879352A - Air supply arrangement and dust catcher

Info

Publication number: CN112879352A
Application number: CN201911199178.2A
Authority: CN
Inventors: 周亚运; 吕琢; 李虎
Original assignee: Guangdong Welling Motor Manufacturing Co Ltd
Current assignee: Guangdong Welling Motor Manufacturing Co Ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2021-06-01
Anticipated expiration: 2039-11-29
Also published as: CN112879352B

Abstract

The invention provides an air supply device and a dust collector, wherein the air supply device is provided with an air supply outlet and comprises a rotating shaft, an impeller which is arranged on the rotating shaft and corresponds to the position of the air supply outlet and a diffuser which is arranged on one side of the impeller, which is far away from the air supply outlet: the diffuser comprises a base, a first blade row and a second blade row which are arranged on the outer ring surface of the base at intervals from top to bottom, the first blade row comprises a plurality of first stationary blades which are arranged convexly at intervals along the circumferential direction, and the second blade row comprises a plurality of second stationary blades which are arranged convexly at intervals along the circumferential direction; the second stationary blades and the adjacent first stationary blades are oppositely arranged at intervals to form a flow guide channel, and the flow guide channel gradually turns to the outer ring surface of the base in the direction from the impeller to the diffuser. The technical scheme of the invention can effectively guide the airflow and reduce the direct impact of the airflow on components such as a motor and the like, thereby reducing the flow loss, improving the efficiency of the air supply device and reducing the power consumption.

Description

Air supply arrangement and dust catcher

Technical Field

The invention belongs to the technical field of dust collection equipment, and particularly relates to an air supply device and a dust collector.

Background

With the increasing living standard of people, more and more consumers begin to use the dust collector for cleaning. The dust collector generally includes a rotating shaft, an impeller arranged on the rotating shaft, a motor driving the rotating shaft to rotate, a diffuser arranged at the rear of the impeller, a frame arranged at the rear of the diffuser and connected with the motor, and a fan cover covering the impeller and the diffuser; when the fan is in actual use, the motor drives the impeller to rotate, a large vacuum degree is formed at the air supply outlet of the fan cover, airflow is sucked from the air supply outlet, and flows out after passing through the diffuser, the rack and the motor at the rear part after obtaining large kinetic energy through the impeller flow passage. However, in the existing vacuum cleaners, especially the handheld vacuum cleaners, because the volume of the air supply device used therein is usually small and the rotation speed is usually high, which is between 8 ten thousand rpm and 15 ten thousand rpm, when the air flow passes through the diffuser and the motor at the rear part in the flowing process, the air flow which is not guided directly impacts the frame and the motor, so that the flowing loss is very large, the efficiency of the air supply device is low, and the power consumption is increased.

Disclosure of Invention

The embodiment of the invention aims to overcome the defects of the prior art and provides an air supply device, which aims to solve the problems of large flow loss, low efficiency and large power consumption of the air supply device of the existing dust collector.

An embodiment of the present invention provides an air supply device, which has an air supply outlet, and includes:

a rotating shaft is arranged at the position of the rotating shaft,

the impeller is arranged on the rotating shaft and corresponds to the position of the air supply outlet; and the number of the first and second groups,

the diffuser is arranged on one side, away from the air supply outlet, of the impeller and comprises an annular base, and a first blade row and a second blade row which are arranged on the outer ring surface of the base at intervals up and down, wherein the first blade row comprises a plurality of first stationary blades which are arranged in a protruding mode at intervals along the circumferential direction, and the second blade row comprises a plurality of second stationary blades which are arranged in a protruding mode at intervals along the circumferential direction;

the second stationary blades and the adjacent first stationary blades are oppositely arranged at intervals to form a flow guide channel, and the flow guide channel gradually turns to the outer ring surface of the base in the direction from the impeller to the diffuser.

Optionally, on a first planar cascade diagram formed after a circumferential horizontal section taken at a height middle position of the first stationary blade is unfolded, a connecting line of corresponding points of the tail part of the first stationary blade, which is away from the base, is a first forehead line, a line connected by the thickness midpoint of the first stationary blade is a first center line, and an included angle between an extension line of the first center line at the tail part of the first stationary blade and a tangent line of the first forehead line at the tail part of the first stationary blade is a first outlet placing angle β 1; on a second planar cascade diagram formed after a circumferential vertical section taken at the middle position of the thickness of the second stationary blade is unfolded, a connecting line of corresponding points of the second stationary blade facing the head of the impeller is a second forehead line, a line formed by connecting the middle points of the thickness of the second stationary blade is a second middle line, and an included angle formed by the extension line of the second middle line at the head of the second stationary blade and the second forehead line is an inlet placing angle alpha 2; α 2 ═ β 1 ± 10 °.

Optionally, the air supply arrangement is still including installing the diffuser deviates from the frame of the one end of impeller, the frame includes inner tube and urceolus, the internal face of urceolus with connect through a plurality of splice bars of arranging along circumference interval between the outer wall of inner tube, just the quantity of second stationary blade with the quantity of splice bar is multiple relation, at least part the second stationary blade with the splice bar position one-to-one.

Optionally, the plurality of connecting ribs are symmetrically arranged in a manner of radiating outwards from the center of the rack.

Optionally, the base includes an upper ring section facing the impeller and a lower ring section facing the frame, the first stator blades are uniformly spaced on an outer ring surface of the upper ring section, and the second stator blades are uniformly spaced on an outer ring surface of the lower ring section.

Optionally, along the protruding a plurality of connection bosss that are equipped with of circumference on the outer wall of inner tube, the inner ring face of diffuser with the outer wall adaptation of inner tube is cup jointed, the lower extreme face indent of diffuser is formed with keeps away the position groove, it has the overlap joint district on the tank bottom in position groove to keep away, the overlap joint district is close to the inner ring face setting of diffuser, and with the top end face adaptation overlap joint of connection boss.

Optionally, the air supply device further comprises a motor and a fan housing provided with the air supply outlet, the motor is mounted on the rotating shaft and located below the rack, and the connecting rib is provided with a mounting hole for connecting with the motor;

the fan housing encloses the impeller and the diffuser.

Optionally, on the first planar cascade diagram, a connecting line of the first stationary blade towards the corresponding point of the head of the base is a first forehead line, and an included angle between an extension line of the head of the first stationary blade and a tangent line of the first forehead line at the head of the first stationary blade is an inlet placing angle α 1, wherein an angle of α 1 is in a range of 25 ° to 60 °.

Optionally, the diffuser has a meridian projection plane, the head of the first stationary blade is projected on the meridian projection plane to obtain a leading edge line, the outer ring surface of the base corresponds to an outer curve on the meridian projection plane, an intersection point of the outer curve and the leading edge line is a first intersection point, an included angle between tangent lines of the leading edge line and the outer curve at the first intersection point is θ 1, and an angle range of θ 1 is 70 ° to 110 °;

the tail of the first stationary blade is projected on the meridian projection plane to obtain a tail edge line, an intersection point of the outer curve and the tail edge line is a second intersection point, an included angle between the tail edge line and a tangent line of the outer curve at the second intersection point is theta 2, and the angle range of the theta 2 is 70 degrees to 110 degrees.

The embodiment of the invention also provides a dust collector which comprises the air supply device.

Based on the structural design, in the technical scheme of the embodiment of the invention, after the airflow comes out from the impeller rotating at high speed, the airflow flows to the motor of the air supply device through the cavity space at the outer side of the diffuser, because two rows of static blades are arranged on the diffuser, namely a first blade row consisting of a plurality of first static blades and a second blade row consisting of a plurality of second static blades, and a specially designed angular relationship range alpha 2 between an outlet installation angle beta 1 at the tail part of the first static blade and an inlet installation angle alpha 2 at the head part of the second static blade is beta 1 +/-10 degrees, a flow guide channel capable of effectively guiding the airflow can be formed between the first static blade and the second static blade corresponding to the positions in the angular relationship range, so that the airflow can gradually deviate from the original flow direction, the direct impact of the airflow on the motor can be reduced, and more impact kinetic energy can be converted into static pressure, thereby reducing the flow loss of the air flow, being beneficial to improving the efficiency of the air supply device and reducing the energy consumption.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic cross-sectional view of an air supply device according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of a diffuser and a frame of an air supply device according to an embodiment of the present invention in an assembled state;

FIG. 3 is an exploded view of a diffuser and a frame of an air supply device according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a diffuser according to an embodiment of the present invention;

FIG. 5 is a first planar vane diagram of the diffuser of FIG. 4 provided in accordance with an embodiment of the present invention;

FIG. 6 is a second planar vane diagram of the diffuser of FIG. 4 provided by an embodiment of the present invention;

FIG. 7 is a schematic cross-sectional view of a diffuser of an air supply device according to an embodiment of the present invention, taken along a meridian projection plane;

FIG. 8 is a meridional projection of the stationary vane of FIG. 7 as provided by an embodiment of the present invention.

The reference numbers illustrate:

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It should be noted that the terms of orientation such as left, right, up and down in the embodiments of the present invention are only relative to each other or are referred to the normal use state of the product, and should not be considered as limiting.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner" and "outer" etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The embodiment of the invention provides an air supply device.

Referring to fig. 1, 2 and 5, in an embodiment, the blowing device has a blowing opening 710 including a rotating shaft 100, an impeller 200 and a diffuser 300; the impeller 200 is installed on the rotation shaft 100 and corresponds to the air supply opening 710; the diffuser 300 is disposed on a side of the impeller 200 facing away from the air supply opening 710, and includes an annular base 310, and a first blade row and a second blade row which are arranged on an outer annular surface of the base 310 at intervals up and down, the first blade row includes a plurality of first stationary blades 320 which are arranged at intervals in the circumferential direction, and the second blade row includes a plurality of second stationary blades 330 which are arranged at intervals in the circumferential direction. The second stationary blades 330 are spaced apart from the adjacent first stationary blades 320 to form a guide passage, which gradually turns toward the outer circumferential surface of the base 310 in a direction from the impeller 200 to the diffuser 300. Specifically, as shown in fig. 4 and 5, on a first planar cascade diagram formed after a circumferential horizontal section taken at a height intermediate position of the first vane 320 is developed, a connecting line of corresponding points of the tail portion of the first vane 320 facing away from the base 310 is a first forehead line 11, a line connected by a thickness midpoint of the first vane 320 is a first center line 12, and an included angle between an extension line of the first center line 12 at the tail portion of the first vane 320 and a tangent line of the first forehead line 11 at the tail portion of the first vane 320 is a first outlet placement angle β 1; on a second planar cascade diagram formed by unfolding a circumferential vertical section taken at a thickness middle position of the second stationary blade 330, a connecting line of corresponding points of the head of the second stationary blade 330 facing the impeller 200 is taken as a second frontal line 21, a line formed by connecting thickness middle points of the second stationary blade 330 is taken as a second middle line 22, and an included angle between an extension line of the head of the second stationary blade 330 and the second frontal line 21 of the second middle line 22 is taken as an inlet placing angle α 2; α 2 ═ β 1 ± 10 °. Of course, after many experimental tests, the angular relationship between α 2 and β 1 may further preferably be in a range of α 2 ═ β 1 ± 2 °, and of course, α 2 ═ β 1 has the optimal flow guiding performance for the airflow.

Based on the structural design, in the embodiment, after the airflow comes out from the impeller 200 rotating at a high speed, the airflow will flow to the motor 600 of the air supply device through the cavity space outside the diffuser 300, because two rows of stationary blades are arranged on the diffuser 300, that is, a first blade row composed of a plurality of first stationary blades 320 and a second blade row composed of a plurality of second stationary blades 330, and a specially designed angular relationship range α 2 ═ β 1 ± 10 ° is provided between an outlet installation angle β 1 at the tail of the first stationary blade 320 and an inlet installation angle α 2 at the head of the second stationary blade 330, a flow guide channel capable of effectively guiding the airflow can be formed between the first stationary blade 320 and the second stationary blade 330 corresponding to the positions within the angular relationship range, so that the airflow can gradually deviate from the original flow direction, thereby reducing the direct impact of the airflow on the motor 600 and converting more impact kinetic energy into static pressure, thereby reducing the flow loss of the air flow, being beneficial to improving the efficiency of the air supply device and reducing the energy consumption.

It should be noted that the air supply device is particularly suitable for a handheld dust collector, and the air supply device of the dust collector comprises the related components such as the circuit board 500, the motor 600 and the fan cover 700 besides the above structure. The fan housing 700 covers the impeller 200 and the diffuser 300 from the air supply opening 710 to the motor 600 from the top, and has an air supply opening 710 corresponding to the head of the impeller 200; the motor 600 is mounted on the rotating shaft 100 and located below the frame 400, the circuit board 500 is mounted below the motor 600, and the motor 600 is electrically connected with the circuit board 500 and controlled by the relevant control device to open and close and adjust the rotating speed; the rotating shaft 100 has a bearing portion 110, and the bearing portion 110 is fitted into the inner circumferential surface of the inner cylinder 410 of the housing 400. In addition, due to the high-speed rotation of the impeller 200, the air flow thrown from the tail of the air supply opening 710 of the impeller 200, which is away from the fan housing 700, should form a certain inclination angle with the radial direction, so the first stationary blade 320 and the second stationary blade 330 on the diffuser 300 are also arranged in the same rotation direction and form a certain inclination angle with the radial direction, so as to better match the angle of the air flow thrown from the impeller 200, thereby being beneficial to further reducing the air flow impact, improving the air supply efficiency and reducing the electric consumption.

Referring to fig. 1 to 3, in the present embodiment, the blower further includes a frame 400 installed at an end of the diffuser 300 away from the impeller 200, the frame 400 includes an inner cylinder 410 and an outer cylinder 420 coaxially sleeved, an inner wall surface of the outer cylinder 420 is connected to an outer wall surface of the inner cylinder 410 through a plurality of connection ribs 430 arranged at intervals along a circumferential direction, and the number of the second stationary blades 330 is multiple of the number of the connection ribs 430. The frame 400 is mainly used for positioning and mounting the diffuser 300, the connecting rib 430 is provided with a mounting hole 431 for connecting with the motor 600, and the inner cylinder 410 of the frame 400 is fittingly sleeved with the bearing portion 110. Here, the arrangement of the number of the second stationary blades 330 in a multiple relation to the number of the connection ribs 430 facilitates the alignment and installation between the second stationary blades 330 and the frame 400. Further, as shown in fig. 3, in the present embodiment, a large through hole is formed between the inner cylinder 410, the outer cylinder 420 and two adjacent connecting ribs 430 in a surrounding manner, and when the number of the second stationary blades 330 is consistent with the number of the connecting ribs 430, and the positions are designed in a one-to-one correspondence manner, the flow guide channel formed between the first stationary blade 320 and the second stationary blade 330 can be better connected and communicated with the corresponding through hole, so as to facilitate the rapid flow of the air flow, and improve the air supply efficiency.

Further, referring to fig. 2 and 3, in the present embodiment, the connecting ribs 430 are preferably arranged at equal intervals along the circumferential direction, for example, the connecting ribs 430 are arranged symmetrically and radially outward from the center of the rack 400, so that the airflow guiding is more uniform, and the airflow impact pressure on the rack 400 and the motor 600 is more uniform. However, the design is not limited thereto, and in other embodiments, the plurality of connecting ribs 430 may be asymmetrically distributed.

Similarly, referring to fig. 2 to 4, in the present embodiment, the base 310 includes an upper ring section 311 facing the impeller 200 and a lower ring section 312 facing the frame 400, the plurality of first stationary blades 320 are uniformly spaced on an outer ring surface of the upper ring section 311, and the plurality of second stationary blades 330 are uniformly spaced on an outer ring surface of the lower ring section 312, so that the flow guiding and stress distribution of the diffuser 300 are more uniform. Specifically, the head end surface of the second stationary blade 330 facing outward is rounded, and the thickness of the second stationary blade 330 is tapered from the root connected to the connecting rib 430 to the head. Therefore, the shape of the second stationary blade 330 is more close to streamline, so that the airflow passing through the second stationary blade is smoother, and the flow guiding effect is better. In addition, along from last to the bottom direction from impeller 200 to motor 600 again, the outer ring radius of upper ring section 311 increases gradually, and the inner and outer ring radius of lower ring section 312 is unchangeable, so, not only can make things convenient for the installation of diffuser 300 to stabilize, and the outer annular surface of upper ring section 311 has just formed an inclined slope face, thereby further be favorable to the direction and the circulation of air current, and the air current stamping pressure that receives on base 310 also can obtain better stress dispersion and conduction, and then is favorable to improving the life of diffuser 300.

Referring to fig. 1 to 3, in the embodiment, a plurality of connection bosses 450 are convexly disposed on an outer wall surface of the inner cylinder 410 along a circumferential direction, an inner ring surface of the diffuser 300 is in fit connection with the outer wall surface of the inner cylinder 410, a position-avoiding groove 340 is concavely formed in a lower end surface of the diffuser 300 to save space, and a lap joint region is disposed on a bottom of the position-avoiding groove 340, adjacent to the inner ring surface of the diffuser 300, and in fit lap joint with top end surfaces of the connection bosses 450. Of course, in other embodiments, the connection boss 450 may be a full-circle ring design, but the design of this embodiment is not only beneficial to the assembly convenience, but also does not reduce the flow passage area between the two connection ribs 430 due to the shielding to a certain extent. In addition, the bottom of the connection boss 450 is connected with the connection rib 430 to play a role of a certain reinforcing rib, and during actual assembly, the connection boss 450 and the outer wall surface of the inner cylinder 410 form a mounting step, that is, a step-type positioning mounting is formed between the connection boss 450 and the area of the groove bottom of the avoiding groove 340 of the diffuser 300, which is adjacent to the inner ring surface of the diffuser 300.

Further, referring to fig. 7, in the present embodiment, the diffuser 300 has a meridian projection plane 14, the head of the first stationary blade 320 is projected on the meridian projection plane 14 to obtain a leading edge line 16, the outer ring surface of the base 310 corresponds to an outer curve 15 on the meridian projection plane 14, an intersection point of the outer curve 15 and the leading edge line 16 is a first intersection point, an included angle between tangents of the leading edge line 16 and the outer curve 15 at the first intersection point is θ 1, and an angle range of θ 1 is 70 ° to 110 °; the tail of the first stationary blade 320 is projected on the meridian projection plane 14 to obtain a tail edge line 17, an intersection point of the outer curve 15 and the tail edge line 17 is a second intersection point, an included angle between the tail edge line 17 and a tangent line of the outer curve 15 at the second intersection point is theta 2, and the angle range of the theta 2 is 70 degrees to 110 degrees. It can be appreciated that when the two angle designs of the first stationary blade 320 satisfy the aforementioned preferred angle range, the flow kinetic energy loss of the air flow can be further effectively reduced.

Similarly, referring to fig. 4 and 5, in the present embodiment, on the first planar cascade diagram, a connecting line of the first stationary blade 320 toward the corresponding point of the head of the base 310 is a first forehead line 13, an included angle between an extension line of the first centerline 12 at the head of the first stationary blade 320 and a tangent line of the first forehead line 13 at the head of the first stationary blade 320 is an inlet placing angle α 1, wherein an angle of α 1 ranges from 25 ° to 60 °. It will be appreciated that the flow of air from the aft portion of the impeller 200 rotating at high speed is angled in a given direction of rotation, and that the angle at which the first stationary vanes 320 meet the flow of air is more closely matched to the actual flow direction of air when the inlet placement angle α 1 is set within the preferred range of angles. Therefore, more kinetic energy impacted by the airflow can be recovered into static pressure, in other words, the design can effectively reduce the flow kinetic energy loss of the airflow, and further is favorable for further improving the efficiency of the air supply device and reducing the energy consumption.

The invention also provides a dust collector (not shown in the figure), which comprises the air supply device, a main body, a dust collecting cup detachably connected with the main body, a dust collection assembly and the like, wherein the air supply device is accommodated in the main body, an air suction channel of the dust collection assembly is communicated with an air supply outlet of the air supply device, negative pressure can be generated in the main body after the air supply device is started, then outside air containing dust can be sucked into the dust collector through the air suction channel, and then the dust is separated, filtered and collected in the dust collecting cup. The specific structure of the air supply device refers to the above embodiments, and since the dust collector adopts all technical solutions of all the above embodiments, all the beneficial effects brought by the technical solutions of the above embodiments are also achieved, and are not repeated herein.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. An air supply device having an air supply opening, comprising:

a rotating shaft is arranged at the position of the rotating shaft,

2. The air supply apparatus according to claim 1, wherein, in a first planar grid pattern formed by developing a circumferential horizontal cross section taken at a height intermediate position of the first stationary blade, a line connecting corresponding points of a tail portion of the first stationary blade facing away from the base is a first forehead line, a line connecting thickness midpoints of the first stationary blade is a first center line, and an angle between an extension line of the first center line at the tail portion of the first stationary blade and a tangent line of the first forehead line at the tail portion of the first stationary blade is a first outlet placement angle β 1; on a second planar cascade diagram formed after a circumferential vertical section taken at the middle position of the thickness of the second stationary blade is unfolded, a connecting line of corresponding points of the second stationary blade facing the head of the impeller is a second forehead line, a line formed by connecting the middle points of the thickness of the second stationary blade is a second middle line, and an included angle formed by the extension line of the second middle line at the head of the second stationary blade and the second forehead line is an inlet placing angle alpha 2; α 2 ═ β 1 ± 10 °.

3. The blower apparatus of claim 2, further comprising a frame mounted at an end of the diffuser opposite to the impeller, wherein the frame includes an inner cylinder and an outer cylinder, an inner wall surface of the outer cylinder is connected to an outer wall surface of the inner cylinder through a plurality of connecting ribs arranged at intervals in a circumferential direction, a number of the second stationary blades is multiple of a number of the connecting ribs, and at least some of the second stationary blades are in one-to-one correspondence with the positions of the connecting ribs.

4. The air supply arrangement as recited in claim 3, wherein a plurality of said ribs are arranged symmetrically radiating outwardly from a center of said frame.

5. The apparatus of claim 3, wherein the base includes an upper ring section facing the impeller and a lower ring section facing the frame, and wherein the first plurality of stationary vanes are evenly spaced on an outer circumferential surface of the upper ring section and the second plurality of stationary vanes are evenly spaced on an outer circumferential surface of the lower ring section.

6. The blowing device according to claim 3, wherein a plurality of connection bosses are convexly provided on an outer wall surface of the inner cylinder in a circumferential direction, an inner ring surface of the diffuser is fittingly fitted with the outer wall surface of the inner cylinder, a clearance groove is concavely formed in a lower end surface of the diffuser, a lap joint region is provided on a groove bottom of the clearance groove, and the lap joint region is disposed adjacent to the inner ring surface of the diffuser and fittingly overlapped with a top end surface of the connection boss.

7. The air supply device as claimed in claim 3, further comprising a motor and a fan housing provided with the air supply outlet, wherein the motor is mounted on the rotating shaft and located below the frame, and the connecting rib is provided with a mounting hole for connecting with the motor;

the fan housing encloses the impeller and the diffuser.

8. The air supply apparatus according to any one of claims 1 to 7, wherein on the first planar grid pattern, a connection line of the first stationary blade toward a corresponding point of the head portion of the base is a first frontal line, and an angle between an extension line of the first center line at the head portion of the first stationary blade and a tangent line of the first frontal line at the head portion of the first stationary blade is an inlet placement angle α 1, wherein an angle of α 1 ranges from 25 ° to 60 °.

9. The air supply device according to any one of claims 1 to 7, wherein the diffuser has a meridian projection plane on which a leading edge line is projected by the head of the first stationary blade, the outer annular surface of the base has an outer curve corresponding thereto, an intersection of the outer curve and the leading edge line is a first intersection, an angle θ 1 between the leading edge line and a tangent line of the outer curve at the first intersection is an angle in a range of 70 ° to 110 °;

10. A vacuum cleaner comprising an air supply apparatus as claimed in any one of claims 1 to 9.