JP3750050B2 - Electric blower - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric blower, and more particularly to an electric motor used for an electric blower.
[0002]
[Prior art]
9 is a front sectional view of a conventional magnet fixing structure of a rotating electric machine described in, for example, Japanese Utility Model Publication No. 4-111253, FIG. 10 is an exploded perspective view of the stator, and FIG. 11 is a longitudinal sectional view of the stator. .
In the figure, 1a and 1b are a pair of magnets for excitation formed in an arc shape, and 13 is a cylindrical yoke made of a magnetic material for forming a magnetic circuit via the magnets 1a and 1b.
[0003]
14 is made of synthetic resin, and is a bottomed cylindrical exterior member that covers the outer periphery of the yoke 13. The pair of projecting portions 15 are opposed to each other in a substantially C shape projecting from the inner peripheral surface toward the center in the axial direction. A narrow gap 16 is formed between each pair of protrusions 15, and an arcuate recess 17 in which the magnets 1 a and 1 b are mounted is formed between the opposing protrusions 15. Has been. The protruding length of the protruding portion 15 is substantially equal to the width (thickness) of the magnets 1a and 1b.
[0004]
To assemble the magnets 1a and 1b and the yoke 13 as described above, first, the yoke 13 is inserted, and the exterior member 14 that covers the outer periphery of the yoke with resin is formed by molding. Next, the magnets 1 a and 1 b are press-fitted into the recesses 17 formed between the projecting portions 15 facing the exterior member 14. As a result, the magnets 1a and 1b are sandwiched and fixed between the opposing projecting portions 15 to form the stator 10a.
Next, the stator 10a is press-fitted into the cylindrical frame 18 and fixed, and the rotor 11 is rotatably installed in a cylindrical space formed by the magnets 1a and 1b to constitute an electric motor. At this time, a predetermined gap is formed between the inner peripheral surfaces of the magnets 1 a and 1 b and the outer peripheral surface of the rotor 11.
[0005]
FIG. 12 is a longitudinal sectional view of an electric blower incorporating the above-described electric motor. In the figure, 10a is a stator, 11 is a rotor disposed in the stator 10a, and its shaft 12 is rotatably supported by a bearing provided on a frame 18 and a bracket 20 attached to the frame 18. Yes. Reference numeral 21 denotes a blower fan attached to one end of the shaft 12, 22 a guide vane fixed to the bracket 20, and 23 a fan cover that has an intake port 24 and is attached to the bracket 20 to cover the blower fan 21. . Reference numeral 19 denotes an exhaust port provided on the side wall of the frame 18.
[0006]
In the electric blower configured as described above, when the electric motor is energized, the blower fan 21 attached to the shaft 12 of the rotor 11 rotates. As a result, the air flowing in from the intake port 24 passes between the stator 10 a and the frame 18 through the fan 21 and the guide vanes 22 and is discharged from the exhaust port 19. Further, the heat generated in the stator 10a and the rotor 11 is discharged from the exhaust port 19 together with the above-described air flow, and the cooling of the electric motor is maintained.
[0007]
[Problems to be solved by the invention]
In the electric blower configured as described above, the outer periphery of the yoke 13 is covered by the exterior member 14, so that the heat generated in the stator 10a and the rotor 11 when the electric motor is driven contacts the aforementioned air flow. Can not be discharged. For this reason, not only the heat generated from the stator 10a but also the heat generated from the rotor 11 cannot be released through the yoke 13, and is slightly formed between each pair of protrusions 15 of the exterior member 14. It is only released by touching the air flow through the narrow gap 16. As a result, the amount of heat released from the electric motor is suppressed, the temperature rises, and the reliability may decrease.
[0008]
Further, since both end faces of the magnets 1a and 1b are only fixed by the protrusions 15 provided on the exterior member 14, it is difficult to ensure the holding strength in the axial direction (vertical direction in FIG. 10). There is a possibility that the magnets 1a and 1b may be damaged during the press-fitting.
Further, when the electric motor is driven, the reaction force by the rotor 11 acts on the magnets 1a and 1b, and the magnets 1a and 1b are fixed not only in the axial direction but also in the rotational direction of the rotor 11 with the recent increase in speed. Although securing the holding force is also important, these measures are insufficient with the above-described fixing means.
[0009]
Further, since the outer peripheral surface of the yoke 2 is covered with the exterior member 14, the amount of resin material required for molding per unit increases, which not only increases the material cost, but also in the mold. There is a possibility that the inner peripheral portion of the yoke 13 is deformed by the molding pressure for filling the material.
[0010]
The present invention has been made in order to solve the above-described problems, and an object thereof is to provide an electric blower including the following electric motor.
(1) The heat dissipation effect of the rotor and the yoke when the motor is driven can be improved.
(2) In molding for fixing the magnet to the yoke, the magnet can be securely fixed with a small amount of molding material without damaging the magnet.
(3) The magnet fixed to the yoke by molding can be securely held in the rotational direction and the axial direction.
[0011]
[Means for Solving the Problems]
(1) An electric blower according to the present invention includes a blower fan, an electric motor, a frame on a substantially bottomed cylinder in which the electric motor is accommodated, and the like, and an electric flow in which an air flow from the blower fan passes through the electric motor. In the blower, a yoke having a circular opening at the center and formed in a substantially square shape and press-fitted and supported in the frame, and a plurality of arc-shaped magnets along the inner peripheral surface of the circular opening of the yoke A stator and a rotor disposed in a space formed in the center by the magnet, and a yoke and a magnet constituting the stator are inserted to insert the yoke and the magnet in the circumferential direction and the axial direction. The end portion is integrally fixed by a holding member formed by molding.
[0012]
(2) Further, the stator of the above (1) is composed of a plurality of arc-shaped magnets disposed between the end portions through a predetermined gap, and the gap formed between the end portions of the magnets, An electric motor in which a ventilation air passage for airflow is formed from the blower fan is provided.
[0013]
(3) Protrusions are provided at positions corresponding to both end portions of the magnet on the inner peripheral surface of the yoke of (1) or (2).
(4) The inclined surface was provided in the circumferential direction both ends outer peripheral side of the magnet in any one of said (1) thru | or (3).
(5) A through hole is provided at a position corresponding to the holding member of the yoke of any one of (1) to (4).
[0014]
DETAILED DESCRIPTION OF THE INVENTION
[Embodiment 1]
FIG. 1 is a front sectional view of Embodiment 1 of an electric motor used for an electric blower according to the present invention, FIG. 2 is an exploded perspective view of the stator, and FIG. 3 is a longitudinal sectional view of the stator.
In the figure, reference numerals 1a and 1b denote a pair of magnets for excitation having a circular arc shape and an axial height H arranged along the inner peripheral surface of a circular opening provided in a yoke described later (in the figure). Is shown in the case of two), and both end portions thereof are tapered in the radial direction. The arc-shaped outer peripheral surfaces of the magnets 1a and 1b are formed shorter than the length obtained by dividing the length of the inner peripheral surface of a circular opening of a yoke described later by the number of magnets 1a and 1b. .
[0015]
2 is a yoke made of a magnetic material and forming a magnetic circuit via the magnets 1a and 1b. The plane shape is substantially quadrangular, and the four corners are formed in an arc shape that matches the inner peripheral surface of the frame 18 described later. A circular opening 3 having the same radius as the outer peripheral surfaces of the magnets 1a and 1b is formed at the center.
The yoke 2 is formed by punching a plate material having high magnetic permeability into the above-described shape and stacking and fixing it so that the thickness becomes h (however, h <H). You may process and form the member of h in the above-mentioned shape.
[0016]
Reference numeral 5 denotes a holding member made of a synthetic resin for fixing the yoke 2 and both end portions of the magnets 1a and 1b disposed opposite to each other in the circular opening.
Reference numeral 18 denotes a cylindrical frame into which the yoke 2 integrated with the magnets 1a and 1b is press-fitted.
Reference numeral 11 denotes a rotor rotatably disposed in a hollow portion formed by the inner peripheral surfaces of the magnets 1a and 1b. Reference numeral 12 denotes an axis of the rotor between the rotor 11 and the inner peripheral surfaces of the magnets 1a and 1b. For example, a gap of about 1 mm is formed.
[0017]
In order to manufacture the electric motor as described above, as shown in FIGS. 1 to 3, the magnets 1 a and 1 b are inserted with their outer peripheral surfaces abutting against the inner peripheral surface of the circular opening 3 of the yoke 2 and positioned. To do. At this time, a gap is formed between the ends of the adjacent magnets 1a and 1b. Next, as shown in FIG. 4, the magnets 1a and 1b and the yoke 2 are inserted, and by molding, both end surfaces of the magnets 1a and 1b, the upper and lower surfaces in the vicinity thereof, and the inner periphery of the yoke 2 in the vicinity thereof The holding member 5 is formed on the surface and the upper and lower surfaces, and these are integrally joined to constitute the stator 10. Then, if the stator 10 is press-fitted into the frame 18 and the rotor 11 is disposed in the hollow portion formed between the magnets 1a and 1b, an electric motor is formed.
[0018]
FIG. 5 is a longitudinal sectional view of the electric blower provided with the above-described electric motor, and the configuration thereof is substantially the same as the conventional electric blower described in FIG. 12 except for the electric motor, but the height of the electric motor in the axial direction is low. Therefore, the size can be reduced as a whole.
[0019]
In the electric fan of the electric blower configured as described above, the heat generated from the yoke 2 and the rotor 11 during driving thereof is the inner peripheral surface of the yoke 2, the pair of holding members 5 facing each other, and the outer peripheral surface of the rotor 11. The airflow flowing in from the intake port 24 is merged through the large ventilating air passage 3a surrounded by, and discharged from the exhaust port 19. For this reason, since the heat generated from the yoke 2 and the rotor 11 can be efficiently released to the outside, the efficiency and durability of the electric motor can be improved and the reliability can be increased.
[0020]
In addition, the magnets 1a and 1b are fixed by the holding member 5 only at both end portions of the magnets 1a and 1b and the yoke 2 in the vicinity thereof, and most of the yoke 2 is exposed. The flow can be brought into contact with the surface of the yoke 2, and the heat generated from the stator 10 can be efficiently released.
Furthermore, since the holding member 5 wraps both end portions of the tapered magnets 1a and 1b from the axial direction and the rotational direction, a high holding force can be obtained.
[0021]
Further, at the time of molding, the molding pressure acts only on and near the end faces of the magnets 1a and 1b, and the pressure acts in the direction of the arc center of the magnets 1a and 1b, so that the magnets 1a and 1b are prevented from being damaged. Can do.
Furthermore, since the volume of the holding member 5 is small, the cost can be reduced with a small amount of the molding material, and the molding pressure can be suppressed because it is easy to fill the entire mold material with the molding material.
[0022]
[Embodiment 2]
FIG. 6 is a front sectional view of a second embodiment of the electric motor used in the electric blower according to the present invention. For ease of explanation, some holding members are omitted. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
In the figure, reference numeral 6 denotes a protrusion projecting toward the center in the axial direction at positions corresponding to both ends of the magnets 1a and 1b on the inner peripheral surface of the yoke 2, and the protrusion length thereof is the same as that of the magnets 1a and 1b. It is about half of the width direction (thickness).
[0023]
In the present embodiment configured as described above, the magnets 1 a and 1 b are inserted between the protrusions 6 along the inner peripheral surface of the circular opening 3 of the yoke 2 on the outer peripheral surface thereof. Then, as in the case of the first embodiment, the holding member 5 is formed by molding, and both the magnets 1a, 1b and the yoke 2 are integrally coupled to form the stator 10.
[0024]
The effect of the present embodiment is the same as that of the first embodiment, but the provision of the protrusion 6 makes it easy to position the magnets 1a and 1b with respect to the yoke 2, and the holding member 5 In addition to the magnets 1a and 1b and the yoke 2, the projection 6 is also wrapped, so that a higher holding force can be ensured.
[0025]
[Embodiment 3]
FIG. 7 is an explanatory diagram of a main part of a third embodiment of the electric motor used in the electric blower according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as Embodiment 1, 2, and description is abbreviate | omitted.
In the present embodiment, in the first or second embodiment (the case of the second embodiment is shown in the drawing), the magnets 1a and 1b are cut from the outer peripheral surface to both end surfaces, and the inclined surface 7 is provided. Is.
The manufacturing procedure of the stator 10 according to the present embodiment is almost the same as that of the first embodiment.
[0026]
The effect of the present embodiment is almost the same as that of the first or second embodiment. In addition to this, inclined surfaces 7 are provided at both ends of the magnets 1a and 1b, and the inclined surface 7 and the yoke 2 are provided. Or the hollow portion 8 is formed between the inclined surface 7 and the inner peripheral surface of the yoke 2 and the side surface of the projecting portion 6. Holding power can be further increased.
[0027]
[Embodiment 4]
FIG. 8 is an explanatory diagram of a main part of a fourth embodiment of the electric motor used in the electric blower according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as Embodiment 1, 2, and description is abbreviate | omitted.
In the present embodiment, a through hole 9 is provided at a position where the holding member 5 of the yoke 2 is provided in the first, second or third embodiment (the case of the second embodiment is shown in the drawing). The manufacturing procedure is almost the same as that in the first embodiment.
[0028]
The effect of the present embodiment is almost the same as in the case of the first, second or third embodiment. In addition, since the through hole 9 is provided in the yoke 2, the mold is formed in the through hole 9 during molding. Since the material is filled, the holding force can be further increased.
[0029]
【The invention's effect】
(1) An electric blower according to the present invention has a circular opening at the center and is formed in a substantially square shape and is press-fitted and supported in the frame, and a circle along the inner peripheral surface of the circular opening of the yoke. A stator composed of a plurality of arc-shaped magnets and a rotor disposed in a space formed in the center by the magnet, and a yoke and a magnet constituting the stator are inserted to surround the yoke and the magnet. Since the end in the direction and the axial direction are fixed together by a holding member formed by molding, the output pressure of the molding material is applied in the direction of the arc center of the magnet, so there is no risk of the magnet breaking and high holding Power can be secured. In addition, since the volume of the holding member is small, the amount of the molding material used can be reduced, thereby reducing the cost.
[0030]
(2) In addition, an electric motor that forms an air flow path for the air flow from the blower fan by the gap formed between the end portions of the magnet of (1) above , and efficiently generates heat from the yoke and the rotor. Therefore, the effectiveness and durability of the electric motor are improved and the reliability can be improved.
[0031]
(3) Since the protrusions are provided at positions corresponding to both end portions of the magnet on the inner peripheral surface of the yoke of (1) or (2), they are installed in the yoke in accordance with the effect of (2). Positioning of the magnet is facilitated, and furthermore, since the holding member wraps the protruding portion in addition to the magnet and the yoke, a higher holding force can be ensured.
[0032]
(4) An inclined surface is provided on both outer circumferential sides of the magnet in any one of the above (1) to (3), and the hollow material formed by the inclined surface is filled with the molding material when molding the holding member. As a result, a higher holding force can be secured.
[0033]
(5) Since a through hole is provided at a position corresponding to the holding member of the yoke of any one of the above (1) to (4), and the molding material of the holding member is filled with the molding material, Furthermore, a high holding force can be ensured.
[Brief description of the drawings]
FIG. 1 is a front sectional view of Embodiment 1 of an electric motor used for an electric blower according to the present invention.
FIG. 2 is an exploded perspective view of the stator of FIG.
FIG. 3 is a longitudinal sectional view of the stator shown in FIG.
4 is an explanatory diagram of a main part of FIG. 1. FIG.
5 is a longitudinal sectional view of an electric blower including the electric motor according to Embodiment 1. FIG.
FIG. 6 is a front sectional view of Embodiment 2 of an electric motor used for an electric blower according to the present invention.
FIG. 7 is an explanatory diagram of a main part of a third embodiment of the electric motor used for the electric blower according to the present invention.
FIG. 8 is an explanatory diagram of a main part of a fourth embodiment of the electric motor used for the electric blower according to the present invention.
FIG. 9 is a front sectional view of an example of a conventional magnet fixing structure of a rotating electric machine.
10 is an exploded perspective view of the stator of FIG. 9. FIG.
11 is a longitudinal sectional view of the stator of FIG. 9. FIG.
12 is a longitudinal sectional view of an electric blower provided with the rotating electrical machine of FIG. 9. FIG.
[Explanation of symbols]
1a, 1b Magnet, 2 yoke, 3 circular opening, 3a ventilation air passage, 5 holding member, 6 protrusion, 7 inclined surface, 9 through hole, 10 stator, 11 rotor, 18 frame, 19 exhaust port, 21 Fan for blowing air, 24 inlets.

Claims (5)

In the electric blower which consists of a blower fan, an electric motor, a frame on a substantially bottomed cylinder in which the electric motor is accommodated, and the like, and an air flow from the blower fan passes through the electric motor,
A yoke which has a circular opening at the center and is formed in a substantially quadrangular shape and is press-fitted and supported in the frame; and a stator comprising a plurality of arc-shaped magnets along the inner peripheral surface of the circular opening of the yoke; A rotor disposed in a space formed in the central portion by the magnet, and a yoke and a magnet constituting the stator are inserted to provide circumferential and axial ends of the yoke and the magnet. An electric blower characterized by being integrally fixed by a holding member formed by molding.   The stator is composed of a plurality of arc-shaped magnets disposed between the end portions with a predetermined gap, and air flow from the blower fan is caused by the gaps formed between the end portions of the magnets. The electric blower according to claim 1, further comprising an electric motor having an air passage.   The electric blower according to claim 1 or 2, wherein protrusions are provided at positions corresponding to both end portions of the magnet on the inner peripheral surface of the yoke. The electric blower according to any one of claims 1 to 3, wherein inclined surfaces are provided on both outer circumferential sides of the magnet in the circumferential direction .   The electric blower according to any one of claims 1 to 4, wherein a through hole is provided at a position corresponding to the holding member of the yoke.

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