IMPELLER FOR ELECTRIC BLOWER

Abstract

Embodiments of the invention provide an impeller for an electric blower. The impeller includes a hub and a shroud disposed to correspond to the hub so that an internal space and an outlet are formed between the hub and the shroud and including an inlet formed therein to introduce air and a disk part formed from the inlet toward an outside. The impeller further includes a blade disposed in the internal space between the shroud and the hub, whereby a distance from a leading edge of the blade positioned at the inlet side to the center of the inlet is the same as a minimum distance from a rim of the inlet to the center of the inlet.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of and priority under 35 U.S.C. §119 to Korean Patent Application No. KR 10-2013-0091127, entitled “IMPELLER FOR ELECTRIC BLOWER,” filed on Jul. 31, 2013, which is hereby incorporated by reference in its entirety into this application.

BACKGROUND

1. Field of the Invention

The present invention relates to an impeller for an electric blower.

2. Description of the Related Art

A conventional impeller has been described in Korean Patent Application Nos. KR 10-2004-0082111 (“KR '111”) and KR 10-2005-0014536 (“KR '536”). According to KR '111 and KR '536, the impeller has been generally called a blowing fan and has been mounted in a cleaner motor and has been used to suck air.

The conventional impeller, as described in these two documents, is configured to include a shroud having an inlet, a hub disposed to correspond to the shroud with an internal space disposed therebetween, and having a shaft hole formed at the center thereof so that a shaft is coupled thereto, and a plurality of blades radially disposed in the internal space and curved in a length direction, respectively.

According to KR '111 and KR '536, when the conventional impeller rotates together with the shaft, the air is sucked through the inlet formed in the shroud, is guided by the respective blades, is radially dispersed, and is then forwarded outwardly.

Meanwhile, as one of factors deteriorating performance of the conventional impeller, there is a delamination phenomenon of the shroud by a flow generated at the inlet formed in the shroud. As several causes of the delamination phenomenon, there are insufficient guidance of a flow by the blades, a rapid change in a channel area.

Generally, a leading edge of the conventional impeller is formed so that a point at which the shroud and the blade meet each other and a point at which the blade and the hub meet each other is connected to each other in a straight line form, similar to the conventional impeller described in KR '111, or is formed so that they are connected to each other in a curved line form, similar to the conventional impeller described in KR '536, and the blade has a height equal to or higher than that of a distal end of the impeller. In addition, a distance from the center C of the impeller to the blade is larger than a radius of the inlet.

Thus, since a radius from the center of the conventional impeller to a point at which the blade and the shroud meet each other is larger than that of the inlet, a space in which air introduced through the inlet of the conventional impeller is not guided by the blade is formed, and the delamination phenomenon occurs in this space.

In addition, a ratio between an inlet area of the conventional impeller and an inlet area of the blade obtained by rotating a straight line vertically connected from a point at which the blade meets the shroud to the hub by 360 degrees is excessively large, the flow rapidly decreases to increase the delamination phenomenon of the shroud by the flow.

In the conventional impeller according to KR '111 and KR '536, since only a curvature of a point at which the shroud and the blade meet each other is managed as a design factor, there is a limitation in decreasing the delamination phenomenon of the entire shroud generated by the flow, which hinders improvement of performance of the electric blower.

SUMMARY

Accordingly, embodiments of the invention have been made to solve the above-mentioned problems, and therefore provide an impeller for an electric blower capable of improving suction force and efficiency of the electric blower by solving a delamination phenomenon between a blade and a shroud, which is a problem according to the conventional art, for example, KR '111 and KR '536.

Further, embodiments of the invention have been made in an effort to provide an impeller for an electric blower capable of easily improving suction force and efficiency of the electric blower by improving a blade and a shroud.

According to an embodiment of the invention, there is provided an impeller for an electric blower, including a hub, a shroud disposed to correspond to the hub so that an internal space and an outlet are formed between the hub and the shroud and including an inlet formed therein to introduce air and a disk part formed from the inlet toward an outside, and a blade disposed in the internal space between the shroud and the hub. A distance from a leading edge of the blade positioned at the inlet side to the center of the inlet is the same as a minimum distance from a rim of the inlet to the center of the inlet.

According to an embodiment, a ratio between a height of the leading edge of the blade positioned at the inlet side and a height of a trailing edge of the blade positioned at the outlet side is 2.4 to 2.6.

According to an embodiment, a ratio between a diameter of the outlet and a diameter of the inlet is 2.2 to 2.4.

According to an embodiment, a ratio between an area formed by rotating the leading edge of the blade based on the center of the inlet by 360 degrees and an area of the inlet is 1.4 to 1.5.

According to another embodiment of the invention, there is provided an impeller for an electric blower, including a hub, a shroud disposed to correspond to the hub so that an internal space and an outlet are formed between the hub and the shroud and including an inlet formed therein to introduce air and a disk part rounded in a shape of an oval curved line from the inlet toward an outside, and a blade disposed in the internal space between the shroud and the hub.

According to an embodiment, the center of a curvature of the disk part is formed to be the same as a height at which a leading edge of the blade is connected to the shroud.

According to an embodiment, a ratio between a height of the leading edge of the blade positioned at the inlet side and a height of a trailing edge of the blade positioned at the outlet side is 2.4 to 2.6.

According to an embodiment, a ratio between a diameter of the outlet and a diameter of the inlet is 2.2 to 2.4.

According to an embodiment, a ratio between an area formed by rotating the leading edge of the blade based on the center of the inlet by 360 degrees and an area of the inlet is 1.4 to 1.5.

According to an embodiment, a distance from a leading edge of the blade positioned at the inlet side to the center of the inlet is the same as a distance from a rim of the inlet to the center of the inlet.

According to another embodiment of the invention, there is provided an impeller for an electric blower, including a hub, a shroud disposed to correspond to the hub so that an internal space and an outlet are formed between the hub and the shroud and including an inlet formed therein to introduce air and a disk part formed from the inlet toward an outside, and a blade disposed in the internal space between the shroud and the hub. A distance from a leading edge of the blade positioned at the inlet side to the center of the inlet is smaller than a distance from an outer diameter of the inlet to the center of the inlet.

According to an embodiment, an upper surface of the blade that the air first contacts is inclined at an angle of 0 to 5 degrees in upward and downward directions based on the inlet.

According to an embodiment, a straight line formed at the leading edge of the blade toward the shroud is inclined at an angle of 0 to 5 degrees in forward and backward directions.

According to an embodiment, a ratio between a diameter of the outlet and a diameter of the inlet is 2.2 to 2.4.

According to an embodiment, a ratio between a height of the leading edge of the blade positioned at the inlet side and a height of a trailing edge of the blade positioned at the outlet side is 2.4 to 2.6.

According to an embodiment, a ratio between an area formed by rotating the leading edge of the blade based on the center of the inlet by 360 degrees and an area of the inlet is 1.4 to 1.5.

According to an embodiment, the disk part is rounded in a shape of an oval curved line from the inlet toward an outside.

According to an embodiment, the center of a curvature of the disk part is formed to be the same as a height at which a leading edge of the blade is connected to the shroud.

Various objects, advantages and features of the invention will become apparent from the following description of embodiments with reference to the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

These and other features, aspects, and advantages of the invention are better understood with regard to the following Detailed Description, appended Claims, and accompanying Figures. It is to be noted, however, that the Figures illustrate only various embodiments of the invention and are therefore not to be considered limiting of the invention's scope as it may include other effective embodiments as well.

FIG. 1 is a schematic view showing an impeller for an electric blower according to an embodiment of the invention.

FIG. 2 is a cross-sectional view showing the impeller for an electric blower according to an embodiment of the invention.

FIG. 3 is a partially cut-away perspective view of the impeller for an electric blower according to an embodiment of the invention.

FIG. 4 is an exploded perspective view showing a state in which the impeller for an electric blower according to an embodiment of the invention is installed.

FIG. 5 is a schematic view showing an impeller for an electric blower according to an embodiment of the invention.

FIG. 6 is a cross-sectional view showing the impeller for an electric blower according to another embodiment of the invention.

FIG. 7 is a partially cut-away perspective view of the impeller for an electric blower according to another embodiment of the invention.

FIG. 8 is an exploded perspective view showing a state in which the impeller for an electric blower according to another embodiment of the invention is installed.

FIGS. 9 to 11 are schematic views showing an impeller for an electric blower according to another embodiment of the invention.

FIG. 12 is a cross-sectional view showing the impeller for an electric blower according to another embodiment of the invention.

FIG. 13 is a partially cut-away perspective view of the impeller for an electric blower according to another embodiment of the invention.

FIG. 14 is an exploded perspective view showing a state in which the impeller for an electric blower according to another embodiment of the invention is installed.

DETAILED DESCRIPTION

Advantages and features of the present invention and methods of accomplishing the same will be apparent by referring to embodiments described below in detail in connection with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The embodiments are provided only for completing the disclosure of the present invention and for fully representing the scope of the present invention to those skilled in the art.

For simplicity and clarity of illustration, the drawing figures illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the discussion of the described embodiments of the invention. Additionally, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention. Like reference numerals refer to like elements throughout the specification.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In an impeller for an electric blower according to various embodiments of the invention, a distance from a leading edge of a blade to the center of an inlet through which the air is introduced is equal to a minimum distance from an outer diameter of the inlet to the center thereof in order to prevent a delamination phenomenon due to formation of a space in which the introduced air is not guided by the blade.

According to an embodiment, the blades are radially disposed in an internal space formed by a hub coupled to a shaft of a cleaner motor and a shroud provided with the inlet through which the air is introduced to disperse the air introduced through the inlet. In addition, the respective blades are curved in a length direction at a uniform curvature.

According to an embodiment, the hub, which is coupled to the shaft of the cleaner motor described above to rotate together with the cleaner motor when the cleaner motor rotates, has a hole formed at a central portion thereof to be coupled to the shaft. In addition, the shroud is disposed to correspond to the hub so that an internal space in which the blades are disposed and an outlet through which the air is discharged are formed in the impeller.

According to an embodiment, the shroud and the hub are connected to each other by the blade. As an example, a plurality of slits are formed in each of the shroud and the hub, protrudes inserted into the slits are formed on the blades, and the blades are coupled to the shroud and the hub through the protrusions and the slits and are then fixed thereto by a method such as a caulking method, at an outer portion of the impeller.

Meanwhile, the impeller for an electric blower according to an embodiment of the invention is mounted and used in a scheme in which the hub is coupled to the shaft of the cleaner motor, as described above. Here, the cleaner motor will be schematically described below.

According to an embodiment, the cleaner motor is a switched reluctance motor (SRM) in which both of cores of a stator and a rotor are formed in a magnetic structure, which is a salient pole, and a concentrated type coil is wound only around the stator without forming any excitation device (a winding or a permanent magnet) in the rotor.

Thus, the switched reluctance motor (SRM), which rotates the rotor using a reluctance torque depending on a change in magnetic reluctance, has a low manufacturing cost, hardly requires maintenance, and has an almost permanent lifespan due to high reliability. However, the switched reluctance motor (SRM) is only an example of the cleaner motor. That is, the cleaner motor is not necessarily limited to the switched reluctance motor (SRM).

Meanwhile, in the conventional impeller, only a curvature of a portion at which the leading edge of the blade and the shroud are connected to each other is managed as a design factor. To the contrary, in the impeller for an electric blower according to various embodiments of the invention, a curvature of the entire shroud is defined as an oval, such that a point of inflection is not present.

According to an embodiment, the center of the curvature of the shroud is formed to be substantially the same as a height at which the leading edge of the blade is connected to the shroud. Further, the shroud is divided into two parts: a surface that contacts the blade and a surface that does not contact the blade. The surface of the shroud that contacts the blade is defined using a portion of an oval, and the other surface of the shroud is formed as an extension line to prevent a shape of the shroud from being rapidly changed. Therefore, the shroud is improved as described above to prevent a delamination phenomenon of the shroud by a flow.

On the other hand, in the impeller for an electric blower according to various embodiments of the invention, a ratio between an inlet area of the impeller and an inlet area of the blade formed by rotating a straight line vertically connected from a point at which the blade meets the shroud to the hub by 360 degrees is 1.4 to 1.5, such that a rapid change in a flow area is decreased.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIRST EMBODIMENT

As shown in FIGS. 1 to 3, an impeller 100 according to a first embodiment of the invention includes a blade 130 disposed in an internal space 110a formed between a hub 110 and a shroud 120. Therefore, the shroud 120 and the hub 110 are connected to each other through the blade 130.

According to an embodiment, the hub 110 has a mounting hole 111 formed at a central portion thereof so that a shaft 13 of a cleaner motor 10 is mounted therein and generally has a disk shape. In addition, the shroud 120 includes an inlet 121 formed in a circular shape at a central portion thereof to introduce air and a disk part 122 formed from the inlet 121 toward an outside.

According to an embodiment, the shroud 120 is disposed over the hub 110 to correspond to the hub 110 to form the internal space 110a and an outlet 110b in the impeller 110, and a plurality of blades 130 are radially disposed in the internal space 110a.

According to an embodiment, the blade 130, which is a kind of strip, is curved in a length direction. Here, a distance R1 from a leading edge A-B of the blade 130 positioned at the inlet 121 side formed in the shroud 120 and connecting the shroud 120 and the hub 110 to each other to the center C of the inlet 121 is the same as a minimum distance RA from a rim of the inlet 121 to the center C of the inlet 121.

Thus, as an example, the distance RA from the rim of the inlet 121 to the center C of the inlet 121 is 51.285 mm, and the distance R1 from the leading edge A-B of the blade 130 to the center C1 of the inlet 121 is also 51.285 mm.

Therefore, the distance from the leading edge A-B of the blade 130 to the center C1 of the inlet 121 is the same as the minimum distance from the rim of the inlet 121 to the center C of the inlet 121, such that air introduced through the inlet 121 is directly guided by the leading edge A-B of the blade 130, thereby preventing a delamination phenomenon generated in the conventional impeller.

Meanwhile, a ratio (B1:B2) between a height B1 of the leading edge A-B of the blade 130 positioned at the inlet 121 side and a height B2 of a trailing edge a-b of the blade 130 positioned at the outlet 110a side is 2.4 to 2.6. Thus, as an example, a distance B1 of the leading edge A-B of the blade 130 is 38.01 mm, and a distance B2 of the trailing edge a-b thereof is 15.21 mm.

A ratio (D2:D1) between a diameter D2 of the outlet 110b and a diameter D1 of the inlet 121 is 2.2 to 2.4. As an example, the diameter D1 of the inlet 121 is 94.88 mm. In addition, the diameter D2 of the outlet 110b is 217.14 mm.

When an area formed by rotating the leading edge A-B of the blade 130 based on the center C of the inlet 121 by 360 degrees is defined as F1 and an area of the inlet 121 is defined as F0, a ratio (F1: F0) between F1 and F0 is 1.4 to 1.5.

Thus, F0 is defined as πR1², and F1 is defined as 2πRAB1.

As shown in FIG. 4, the cleaner motor 10 includes a stator 11, a rotor 12, and a shaft 13 configuring a general switched reluctance motor (SRM), wherein the rotor 12 is rotatably installed in the center of the stator 11 and the shaft 13 is installed at the center of the rotor 12. In addition, the hub 110 is mounted around the shaft 13 through the mounting hole 111, such that it rotates when the cleaner motor 10 is driven.

Therefore, in the impeller 100 according to the first embodiment of the invention, the air introduced into the internal space 110a through the inlet 121 when the cleaner motor 10 rotates is guided by the leading edges A-B of the blades 130, is uniformly dispersed by the respective blades 130, and is then discharged finally through the outlet 110b.

SECOND EMBODIMENT

As shown in FIGS. 5 to 7, an impeller 200 according to a second embodiment of the invention includes a blade 230 disposed in an internal space 210a formed between a hub 210 and a shroud 220. Therefore, the shroud 220 and the hub 210 are connected to each other through the blade 230.

According to an embodiment, the hub 210 has a mounting hole 211 formed at a central portion thereof so that a shaft 13 of a cleaner motor 10 is mounted therein and generally has a disk shape. In addition, the shroud 220 includes an inlet 221 formed in a circular shape at a central portion thereof to introduce air and a disk part 222 formed from the inlet 221 toward an outside.

According to an embodiment, the disk part 222 is rounded in a shape of an oval curved line. A curvature of the disk part 222 contacting the blade 230 is formed as the oval curved line to remove a point of inflection, thereby preventing a delamination phenomenon of the shroud 220 generated by a flow. In addition, the center of the curvature of the disk part 222 is formed to be substantially the same as a height at which a leading edge A of the blade 230 is connected to the shroud 220.

Therefore, the shroud 220 is disposed over the hub 210 to correspond to the hub 210 to form the internal space 210a and an outlet 210b in the impeller 200 and stabilize a flow of air discharged to the outlet 210b through the internal space 210, thereby preventing the delamination phenomenon.

According to an embodiment, the blade 230, which is a kind of strip, is curved in a length direction and is radially disposed in the internal space 210a. Here, a distance R1 from a leading edge A-B of the blade 230 positioned at the inlet 221 side formed in the shroud 220 and connecting the shroud 220 and the hub 210 to each other to the center C of the inlet 221 is the same as a minimum distance RA from a rim of the inlet 221 to the center C of the inlet 221.

For example, the distance RA from the rim of the inlet 221 to the center C of the inlet 221 is 51.285 mm, and the distance R1 from the leading edge A-B of the blade 230 to the center C1 of the inlet 221 is also 51.285 mm.

Therefore, the distance from the leading edge A-B of the blade 230 to the center C1 of the inlet 221 is the same as the minimum distance from the rim of the inlet 221 to the center C of the inlet 221, such that air introduced through the inlet 221 is directly guided by the leading edge A-B of the blade 230, thereby preventing a delamination phenomenon generated in the impeller according to the prior art.

Meanwhile, a ratio (B1:B2) between a height B1 of the leading edge A-B of the blade 230 positioned at the inlet 221 side and a height B2 of a trailing edge a-b of the blade 230 positioned at the outlet 210b side is 2.4 to 2.6. For example, a distance B1 of the leading edge A-B of the blade 230 is 38.01 mm, and a distance B2 of the trailing edge a-b thereof is 15.21 mm.

According to an embodiment, a ratio (D2:D1) between a diameter D2 of the outlet 210b and a diameter D1 of the inlet 221 is 2.2 to 2.4. As an example, the diameter D1 of the inlet 221 is 94.88 mm,.In addition, the diameter D2 of the outlet 210b is 21.7.14 mm.

When an area formed by rotating the leading edge A-B of the blade 230 based on the center C of the inlet 221 by 360 degrees is defined as F1 and an area of the inlet 221 is defined as F0, a ratio (F1:F0) between F1 and F0 is 1.4 to 1.5.

Thus, F0 is defined as πR1², and F1 is defined as 2πRAB1.

As shown in FIG. 8, the cleaner motor 10 includes a stator 11, a rotor 12, and a shaft 13 configuring a general switched reluctance motor (SRM), wherein the rotor 12 is rotatably installed in the center of the stator 11 and the shaft 13 is installed at the center of the rotor 12. In addition, the hub 210 is mounted around the shaft 13 through the mounting hole 211, such that it rotates when the cleaner motor 10 is driven.

Therefore, in the impeller 200 according to the second embodiment of the invention, the air introduced into the internal space 210a through the inlet 221 when the cleaner motor 10 rotates is guided by the leading edges A-B of the blades 230, is uniformly dispersed by the respective blades 230 in a state in which a flow of air is stabilized by the disk part 222 of the shroud 220, and is then discharged finally through the outlet 210b.

THIRD EMBODIMENT

As shown in FIG. 9, an impeller 300 according to a third embodiment of the invention includes a blade 330 disposed in an internal space 310a formed between a hub 310 and a shroud 320. Therefore, the shroud 320 and the hub 310 are connected o each other through the blade 330.

According to anembodiment, the blade 330, which is a kind of strip, is curved in a length direction and is radially disposed in the internal space 310a. Here, a distance R1 from a leading edge A-B of the blade 330 positioned at the inlet 321 side formed in the shroud 320 to the center C of the inlet 321 is smaller than a distance RA from a rim of the inlet 321 to the center C of the inlet 321.

For example, when the distance RA from the rim of the inlet 321 to the center C of the inlet 321 is 51.285 mm, the distance R1 from the leading edge A-B of the blade 330 to the center C1 of the inlet 321 is smaller than 51.285 mm. Therefore, the air introduced into the impeller 300 through the inlet 321 is guided by the leading edge A-B of the blade 330, thereby preventing a delamination phenomenon generated in the impeller according to the prior art.

As shown in FIGS. 10 and 11, an upper surface 331 of the blade 330 that the air introduced through the inlet 321 first contacts is inclined based on the inlet 321. As an example, the upper surface 331 is inclined at an angle of 5 degrees in upward and downward directions.

According to an embodiment, a configuration of the leading edge A-B of the blade 330 generally formed at a right angle (90 degrees) to the shroud 320 is improved. As an example, a straight line formed toward the shroud 320 is inclined at an angle of 5 degrees in forward and backward directions.

As shown in FIGS. 12 and 13, the hub 310 has a mounting hole 311 formed at a central portion thereof so that a shaft 13 of a cleaner motor 10 is mounted therein and generally has a disk shape. In addition, the shroud 320 includes an inlet 321 formed in a circular shape at a central portion thereof to introduce air and a disk part 322 formed from the inlet 321 toward an outside.

According to an embodiment, the disk part 322 is rounded in a shape of an oval curved line. A curvature of the disk part 322 contacting the blade 330 is formed as the oval curved line to remove a point of inflection, thereby preventing a delamination phenomenon of the shroud 320 generated by a flow. In addition, the center of the curvature of the disk part 322 is formed to be substantially the same as a height at which a leading edge A of the blade 330 is connected to the shroud 320.

Therefore, the shroud 320 is disposed over the hub 310 so as to correspond to the hub 312 to form the internal space 310a and an outlet 310b in the impeller 300 and stabilize a flow of air discharged to the outlet 310b through the internal space 310, thereby preventing the delamination phenomenon.

Meanwhile, a ratio (B1:B2) between a height B1 of the leading edge A-B of the blade 330 positioned at the inlet 321 side and a height B2 of a trailing edge a-b of the blade 330 positioned at the outlet 310b side is 2.4 to 2.6. For example, a distance B1 of the leading edge A-B of the blade 330 is 38.01 mm, and a distance B2 of the trailing edge a-b thereof is 15.21 mm.

According to an embodiment, a ratio (D2:D1) between a diameter D2 of the outlet 310b and a diameter D1 of the inlet 321 is 2.2 to 2.4. For example, the diameter D1 of the inlet 321 is 94.88 mm. In addition, the diameter D2 of the outlet 310b is 217.14 mm.

In addition, when an area formed by rotating the leading edge A-B of the blade 330 based on the center C of the inlet 321 by 360 degrees is defined as F1 and an area of the inlet 321 is defined as F0, a ratio (F1:F0) between F1 and F0 is 1.4 to 1.5.

Thus, F0 is defined as πR1², and F1 is defined as 2πRAB1.

As shown in FIG, 14, the cleaner motor 10 includes a stator 11, a rotor 12, and a shaft 13 configuring a general switched reluctance motor (SRM), wherein the rotor 12 is rotatably installed in the center of the stator 11 and the shaft 13 is installed at the center of the rotor 12. In addition, the hub 310 is mounted around the shaft 13 through the mounting hole 311, such that it rotates when the cleaner motor 10 is driven.

Therefore, in the impeller 300 according to the third embodiment of the invention, the air introduced into the internal space 310a through the inlet 321 when the cleaner motor 10 rotates is guided by the leading edges A-B of the blades 330, is uniformly dispersed by the respective blades 330 in a state in which a flow of air is stabilized by the disk part 322 of the shroud 320, and is then discharged finally through the outlet 310b.

According to various embodiments of the invention, the distance from the leading edge of the blade to the center of the inlet is the same as the minimum distance from an outer diameter of the inlet to the center of the inlet, such that air introduced through the inlet is guided by the leading edge of the blade, thereby easily preventing a delamination phenomenon. Therefore, suction force and efficiency of the electric blower may be easily improved.

Meanwhile, according to another embodiment of the invention, the shroud includes the disk part rounded in a shape of an oval curved line from the inlet toward an outside to remove a point of inflection in a curvature of the entire shroud, thereby easily preventing a delamination phenomenon of the shroud generated by a flow. Therefore, suction force and efficiency of the electric blower may be easily improved.

On the other hand, according to still another embodiment of the invention, the distance from the leading edge of the blade to the center of the inlet is smaller than the distance from an outer diameter of the inlet to the center of the inlet, such that air introduced through the inlet is guided by the leading edge of the blade, thereby easily preventing a delamination phenomenon. Therefore, suction force and efficiency of the electric blower may be easily improved.

Terms used herein are provided to explain embodiments, not limiting the present invention. Throughout this specification, the singular form includes the plural form unless the context clearly indicates otherwise. When terms “comprises” and/or “comprising” used herein do not preclude existence and addition of another component, step, operation and/or device, in addition to the above-mentioned component, step, operation and/or device.

Embodiments of the present invention may suitably comprise, consist or consist essentially of the elements disclosed and may be practiced in the absence of an element not disclosed. For example, it can be recognized by those skilled in the art that certain steps can be combined into a single step.

The terms and words used in the present specification and claims should not be interpreted as being limited to typical meanings or dictionary definitions, but should be interpreted as having meanings and concepts relevant to the technical scope of the present invention based on the rule according to which an inventor can appropriately define the concept of the term to describe the best method he or she knows for carrying out the invention.

The terms “first,” “second,” “third,” “fourth,” and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Similarly, if a method is described herein as comprising a series of steps, the order of such steps as presented herein is not necessarily the only order in which such steps may be performed, and certain of the stated steps may possibly be omitted and/or certain other steps not described herein may possibly be added to the method.

The singular forms “a,” “an,” and “the” include plural referents, unless the context clearly dictates otherwise.

As used herein and in the appended claims, the words “comprise,” “has,” and “include” and all grammatical variations thereof are each intended to have an open, non-limiting meaning that does not exclude additional elements or steps.

As used herein, the terms “left,” “right,” “front,” “back,” “top,” “bottom,” “over,” “under,” and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein. The term “coupled,” as used herein, is defined as directly or indirectly connected in an electrical or non-electrical manner. Objects described herein as being “adjacent to” each other may be in physical contact with each other, in close proximity to each other, or in the same general region or area as each other, as appropriate for the context in which the phrase is used. Occurrences of the phrase “according to an embodiment” herein do not necessarily all refer to the same embodiment.

Ranges may be expressed herein as from about one particular value, and/or to about another particular value. When such a range is expressed, it is to be understood that another embodiment is from the one particular value and/or to the other particular value, along with all combinations within said range.

Although the present invention has been described in detail, it should be understood that various changes, substitutions, and alterations can be made hereupon without departing from the principle and scope of the invention. Accordingly, the scope of the present invention should be determined by the following claims and their appropriate legal equivalents.

Claims

1. An impeller for an electric blower, comprising:

a hub;

a shroud disposed to correspond to the hub so that an internal space and an outlet are formed between the hub and the shroud and including an inlet formed therein to introduce air and a disk part formed from the inlet toward an outside; and

a blade disposed in the internal space between the shroud and the hub,

wherein a distance from a leading edge of the blade positioned at the inlet side to the center of the inlet is the same as a minimum distance from a rim of the inlet to the center of the inlet.

2. The impeller for the electric blower as set forth in claim 1, wherein a ratio between a height of the leading edge of the blade positioned at the inlet side and a height of a trailing edge of the blade positioned at the outlet side is 2.4 to 2.6.

3. The impeller for the electric blower as set forth in claim 1, wherein a ratio between a diameter of the outlet and a diameter of the inlet is 2.2 to 2.4.

4. The impeller for the electric blower as set forth in claim 1, wherein a ratio between an area formed by rotating the leading edge of the blade based on the center of the inlet by 360 degrees and an area of the inlet is 1.4 to 1.5.

5. An impeller for an electric blower, comprising:

a hub;

a shroud disposed to correspond to the hub so that an internal space and an outlet are formed between the hub and the shroud and including an inlet formed therein to introduce air and a disk part rounded in a shape of an oval curved line from the inlet toward an outside; and

a blade disposed in the internal space between the shroud and the hub.

6. The impeller for the electric blower as set forth in claim 5, wherein a center of a curvature of the disk part is formed to be the same as a height at which a leading edge of the blade is connected to the shroud.

7. The impeller for the electric blower as set forth in claim 5, wherein a ratio between a diameter of the outlet and a diameter of the inlet is 2.2 to 2.4.

8. The impeller for the electric blower as set forth in claim 5, wherein a ratio between a height of the leading edge of the blade positioned at the inlet side and a height of a trailing edge of the blade positioned at the outlet side is 2.4 to 2.6.

9. The impeller for the electric blower as set forth in claim 5, wherein a ratio between an area formed by rotating the leading edge of the blade based on the center of the inlet by 360 degrees and an area of the inlet is 1.4 to 1.5.

10. The impeller for the electric blower as set forth in claim 5, wherein a distance from a leading edge of the blade positioned at the inlet side to the center of the inlet is the same as a minimum distance from a rim of the inlet to the center of the inlet.

11. An impeller for an electric blower, comprising:

a hub;

a shroud disposed to correspond to the hub so that an internal space and an outlet are formed between the hub and the shroud and including an inlet formed therein to introduce air and a disk part formed from the inlet toward an outside; and

a blade disposed in the internal space between the shroud and the hub,

wherein a distance from a leading edge of the blade positioned at the inlet side to the center of the inlet is smaller than a distance from an outer diameter of the inlet to the center of the inlet.

12. The impeller for the electric blower as set forth in claim 11, wherein an upper surface of the blade that the air first contacts is inclined at an angle of 0 to 5 degrees in upward and downward directions based on the inlet.

13. The impeller for the electric blower as set forth in claim 11, wherein a straight line formed at the leading edge of the blade toward the shroud is inclined at an angle of 0 to 5 degrees in forward and backward directions.

14. The impeller for the electric blower as set forth in claim 11, wherein a ratio between a diameter of the outlet and a diameter of the inlet is 2.2 to 2.4.

15. The impeller for the electric blower as set forth in claim 11, wherein a ratio between a height of the leading edge of the blade positioned at the inlet side and a height of a trailing edge of the blade positioned at the outlet side is 2.4 to 2.6.

16. The impeller for the electric blower as set forth in claim 11, wherein a ratio between an area formed by rotating the leading edge of the blade based on the center of the inlet by 360 degrees and an area of the inlet is 1.4 to 1.5.

17. The impeller for the electric blower as set forth in claim 11, wherein the disk part is rounded in a shape of an oval curved line from the inlet toward an outside.

18. The impeller for the electric blower as set forth in claim 17, wherein a center of a curvature of the disk part is formed to be the same as a height at which a leading edge of the blade is connected to the shroud.