JP2007315263A - Electric blower and vacuum cleaner using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric blower capable of reducing noise. <P>SOLUTION: The electric blower comprises a motor 15 having a rotor 5 rotatably held, an impeller 16 mounted to a shaft 6 serving as an output shaft of the rotor 5 and having vanes, an air guide 17 having stator vanes 26 situated around an outer periphery of the impeller 16 and defining a plurality of airflow paths 20, and a fan case 18 covering the air guide 17 and the impeller 16, wherein a plurality of openings 25 are formed in an outer periphery of the fan case 18 for discharging an exhaust wind from the impeller 16 and, provided that the number of the vanes possessed by the impeller 16 is a and the number of the openings of the fan case 18 is c, a and c are set in a relationship of being coprime relatively to each other. Air discharged by the impeller does not flow into the openings at the same timing, noises of collision to the openings are dispersed in timing, and therefore timing of generation of noises is not concentrated. The electric blower of low noise can be thus attained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric blower used for a vacuum cleaner and the like and a vacuum cleaner using the same.

  A configuration of a conventional electric blower will be described with reference to FIG.

  As shown in FIG. 3, the electric blower 1 includes an armature winding (schematic diagram) in a stator 2 having field windings (omitted) on a field core 3 and an armature core 7 passed through a shaft 6. 8, a commutator 9 is arranged coaxially, and a rotor 5 is rotatably fixed by bearings 10 provided at both ends of the shaft 6. The stator 2 and the rotor 5 are fixed to the load side bracket 11 and the anti-load side bracket 12, and a motor 15 is installed by inserting a pair of carbon brushes (not shown) into the anti-load side bracket 12 via the deformed pipe 14. Forming. Reference numeral 19 denotes an exhaust port.

  Further, the shaft 6 of the output shaft is provided with an impeller 16, and an air guide 17 that forms a ventilation path is disposed on the outer peripheral portion of the impeller 16, and the air guide 17 is constituted by the adjacent stationary blades 26 on the upper surface. The air passage 20 has a plurality of passages, a flow changing portion 21 that guides the flow to the lower surface of the air guide 17, and a return passage 22. And the fan case 18 is attached so that these may be covered, and the electric blower 1 is formed. On the outer periphery of the fan case 18, openings 25 are provided at positions corresponding to the individual ventilation paths of the air guide 17. Reference numeral 24 denotes an intake port.

In the above configuration, when electric power is supplied, the current flowing through the field winding is transmitted to the commutator 9 through the carbon brush, and between the magnetic flux generated in the field core 3 and the current passing through the armature winding 8. A force is generated and the rotor 5 rotates. Next, when the rotor 5 rotates, the impeller 16 fixed to the shaft 6 of the rotor 5 rotates, and the air in the impeller 16 increases in speed and is discharged from the impeller 16. A part of the air accelerated by the impeller 16 is linearly discharged from the opening 25 provided on the outer periphery of the fan case 18. Further, a part of the accelerated air passes through the ventilation path 20 of the air guide 17, is decelerated and enters the flow changing unit 21, is changed in direction by about 180 degrees, passes through the return path 22, and goes to the motor 15. It is guided. If the inner surface R shape of the fan case 18 can be set large, when the direction of air flow is changed by 180 degrees, the direction change is performed smoothly and loss can be reduced. And after that, while cooling the rotor 5, the stator 2, and the carbon brush, it discharges | emits from the exhaust port 19 of the anti-load side bracket 12 (for example, refer patent document 1).
Japanese Utility Model Publication No. 61-47964

  In the configuration of the conventional electric blower, most of the air flow that has passed through the ventilation path 20 of the air guide 17 is directly discharged from the opening 25 in the outer peripheral portion of the fan case 18, and the loss is small, leading to improved performance. . However, on the other hand, after passing through the ventilation path 20 of the air guide 17, when the air flow collides with the end face of the opening 25 or when it passes through the opening 25, a collision sound or a passing sound is generated. This leads to an increase in noise of the blower 1. Furthermore, noise generated when the timing of the collision with the openings 25 is dispersed in each opening 25 is reduced, but the same number as the number of the ventilation paths 20 when passing through the ventilation paths 20 of the air guide 17. The air flow bundled in the distribution of the air flows into the same number of openings 25 as the ventilation paths 20. Since the number of distributions of air flows and the same number of openings 25 flow at the same time, collision sounds and friction sounds with the openings 25 are generated at the same timing, increasing noise. Therefore, it has been very difficult to reduce the noise generated from the electric blower 1.

  This invention solves the said subject, and it aims at providing the electric blower which can reduce noise, and the vacuum cleaner carrying it.

  In order to solve the conventional problems, an electric blower of the present invention is attached to a motor having a rotor rotatably held by a load side bracket and an anti-load side bracket, and a shaft that is an output shaft of the rotor. An impeller having blades, an air guide having a stationary blade located on an outer peripheral portion of the impeller, and forming a plurality of ventilation paths, and a fan case covering the air guide and the impeller. Provided on the outer periphery are a plurality of openings for discharging the exhaust air from the impeller, where a is the number of blades of the impeller and c is the number of openings in the fan case. In other words, a and c are set so as not to have a common divisor other than “1”, and the air discharged by the impeller has the same tie. Without flowing into the opening in the ring, since the timing collision noise and openings are distributed, it can realize low noise of the electric blower because not concentrated the timing of occurrence of noise.

  The electric blower of the present invention can be realized with low noise. Moreover, the vacuum cleaner equipped with this electric blower is also low noise and excellent in usability.

  A first invention includes a motor having a rotor rotatably held by a load side bracket and an anti-load side bracket, an impeller attached to a shaft which is an output shaft of the rotor, and having blades, and an outer periphery of the impeller An air guide having a stationary blade positioned at a portion and forming a plurality of ventilation paths; and a fan case covering the air guide and the impeller, and exhausting exhaust air from the impeller to the outer periphery of the fan case When a plurality of openings are provided, the number of blades of the impeller is a, and the number of openings of the fan case is c, a and c are set so as to have a prime relationship with each other, The air discharged by the impeller does not flow into the opening at the same timing, and the timing of the collision noise with the opening is also distributed, so the timing of noise generation is also concentrated Since there is no Rukoto possible to realize a low-noise electric blower.

  A second invention includes a motor having a rotor rotatably held by a load side bracket and an anti-load side bracket, an impeller attached to a shaft which is an output shaft of the rotor and having blades, and an outer periphery of the impeller An air guide having a stationary blade positioned at a portion and forming a plurality of ventilation paths; and a fan case covering the air guide and the impeller, and exhausting exhaust air from the impeller to the outer periphery of the fan case In a configuration in which a plurality of openings are provided, where b is the number of ventilation paths of the air guide and c is the number of openings of the fan case, b and c are set so as to have a prime relationship with each other. Therefore, the air discharged from the air guide does not flow into the opening at the same timing, and the timing of the collision sound with the opening is also distributed. Since there is no also to focus grayed possible to realize a low-noise electric blower.

  According to a third aspect of the present invention, there is provided a motor having a rotor rotatably held by a load side bracket and an anti-load side bracket, an impeller attached to a shaft which is an output shaft of the rotor and having blades, and an outer periphery of the impeller An air guide having a stationary blade positioned at a portion and forming a plurality of ventilation paths; and a fan case covering the air guide and the impeller, and exhausting exhaust air from the impeller to the outer periphery of the fan case When a plurality of openings are provided, the number of blades of the impeller is a, the number of ventilation paths of the air guide is b, and the number of openings of the fan case is c, a, b, and c are The air that is discharged by the impeller does not flow into the ventilation path of the air guide at the same timing, and is discharged from the air guide. Air does not flow into the opening at the same timing, and the timing of the impact sound between the diffuser and the opening is also distributed, and the timing of noise generation is not concentrated. A blower can be realized.

  4th invention is equipped with the dust collection chamber which collects dust, and the electric blower of any one of 1st-3rd invention, By mounting an electric blower of low noise in an electric vacuum cleaner, The noise of the vacuum cleaner can be reduced, and a highly usable vacuum cleaner can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a partial cross-sectional view of the electric blower according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a fan portion when viewed from above (intake port side) of the electric blower. In addition, the same code | symbol is attached | subjected about the same component as a prior art example, and the description is abbreviate | omitted.

  As shown in FIG. 1, the shaft 6 of the output shaft is provided with an impeller 16, and the impeller has a number of blades. An air guide 17 that forms a ventilation path is disposed on the outer periphery of the impeller 16, and the air guide 17 includes b ventilation paths 20 formed between adjacent stationary blades 26 on the surface, and the air guide 17 17 It is comprised by the flow change part 21 guide | induced to the back surface, and the return channel | path 22 further. And the fan case 18 is attached so that these may be covered, and it becomes the electric blower 1. FIG. Reference numeral 24 denotes an intake port. Further, c openings 25 are provided on the outer periphery of the fan case 18 as shown in FIG.

  The operation in the above configuration will be described. When electric power is supplied, the current flowing through the field winding is transmitted to the commutator 9 through the carbon brush (omitted), and the magnetic flux generated in the field core 3 and the armature winding. A force is generated between the current passing through 8 and the rotor 5 rotates. Next, when the rotor 5 rotates, the impeller 16 fixed to the shaft 6 of the rotor 5 rotates, the air in the impeller 16 is accelerated, and the increased air is discharged from the outer peripheral portion of the impeller 16, After passing through the ventilation path 20 of the air guide 17 and passing through the ventilation path 20, a part of the air guide 17 is decelerated and enters the flow changing unit 21, and the remaining air flow is discharged from the opening 25 to the outer periphery of the fan case 18. Is done.

  The exhaust flow passing through each of the ventilation paths 20 of the air guide 17 and discharged from the opening 25 on the outer periphery of the fan case 18 becomes a bundle of b as many as the number b of the ventilation paths 20, and becomes a fan case 18. However, since the number c of the openings 25 is coprime to the number b of the air passages of the air guide 17, no matter which opening 25 of the fan case 18 is taken, Exhaust flows having the same density / velocity distribution state do not flow in at the same timing, but flow into all the openings 25 at different timings. That is, the exhaust flow discharged from the air guide 17 flows into any opening 25 of the fan case 18 with a different density / speed distribution.

  Since the exhaust flow discharged from these air guides 17 does not flow into each opening 25 of the fan case 18 in the same state, the density / velocity distributions do not overlap when capturing a certain moment. The flow does not collide with the ventilation path 20 at the same timing, but collides at different timings. Although airflow noise is generated at the time of a collision, the generation timing of the noise is not concentrated and the noise generation timing can be reduced by shifting the timing of the collision.

  Thus, according to this Embodiment, since generation | occurrence | production of the noise generated by the air flow discharged | emitted from the air guide 17 can be reduced, the low noise electric blower 1 is realizable.

  The impeller 16 is circular and has the same number of blades as the number of blades in the entire circumference, and has a point-symmetric configuration with respect to the rotation center. Due to the configuration of the impeller 16, the density distribution and velocity distribution of the air flow while the impeller 16 is rotating are also a number of point symmetric distributions with respect to the rotation center. That is, when a certain moment of the rotating impeller 16 is captured, a density distribution and speed distribution corresponding to the number of blades are generated on the outer periphery of the impeller 16.

  The discharge flow discharged from the impeller 16 and having a density / velocity distribution that is point-symmetric with respect to the center of rotation of the air guide 17 is opened in any ventilation path 20 while maintaining a certain density / speed distribution. However, since the number c of the openings 25 is coprime to the number of blades a of the impeller 16, no matter which opening 25 of the fan case 18 is taken, the same density / speed distribution is obtained. Are not introduced at the same timing, but are introduced into all the openings 25 at different timings. That is, the exhaust flow discharged from the impeller 16 is in a state where it flows into any opening 25 of the fan case 18 with a different density / speed distribution.

  Since the exhaust flows discharged from the impellers 16 do not flow into the openings 25 of the fan case 18 in the same state, the density / velocity distributions do not overlap when capturing a certain moment. Without colliding with the ventilation path 20 at the same timing, they collide with each shifted timing. Although airflow noise is generated at the time of a collision, the generation timing of the noise is not concentrated and the noise generation timing can be reduced by shifting the timing of the collision.

  As described above, according to the present embodiment, it is possible to reduce the generation of noise generated by the air flow discharged from the impeller 16, so that the low-noise electric blower 1 can be realized.

  Further, as is apparent from the present embodiment, the electric vacuum cleaner provided with the electric blower 1 of the present embodiment can reduce the noise generated from the electric vacuum cleaner, so it has low noise and excellent usability. It is clear that a vacuum cleaner can be provided.

(Embodiment 2)
A second embodiment of the present invention will be described with reference to FIG. The same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The impeller 16 is circular and has the same number of blades as the number of blades in the entire circumference, and has a point-symmetric configuration with respect to the rotation center. Due to the configuration of the impeller 16, the density distribution and velocity distribution of the air flow while the impeller 16 is rotating are also a number of point symmetric distributions with respect to the rotation center. That is, when a certain moment of the rotating impeller 16 is captured, a density distribution and speed distribution corresponding to the number of blades are generated on the outer periphery of the impeller 16.

  The discharge flow of density / velocity distribution that is point-symmetric with respect to the center of rotation discharged from the impeller 16 flows into any one of the ventilation paths 20 of the air guide 17 while maintaining a certain density / speed distribution. However, since the number b of the air guides 20 in the air guide 17 has a prime relationship with the impeller blade number a, no matter which of the air guides 20 in the air guide 17 is taken, the density / speed distribution is the same. The exhaust flow does not flow in at the same timing, but flows into all the ventilation paths 20 at different timings. In other words, the exhaust flow discharged from the impeller 16 is in a state of flowing with a different density / speed distribution into any ventilation path 20 of the air guide 17.

  Further, the exhaust flow that passes through the ventilation path 20 of the air guide 17 and is discharged from the opening 25 on the outer periphery of the fan case 18 is equal to the number c of the opening 25 on the outer periphery of the fan case 18. Therefore, no matter which opening 25 of the fan case 18 is taken, the exhaust flow having the same density and speed distribution is not introduced at the same timing. It flows into the opening 25 at different timings. That is, the exhaust flow discharged from the air guide 17 flows into any opening 25 of the fan case 18 with a different density / speed distribution.

  The exhaust flow discharged from the impeller 16 does not flow into each ventilation path 20 of the air guide 17 in the same state, and the exhaust flow discharged from the air guide 17 does not flow into each opening 25 of the fan case 18. In addition, since the flow does not flow in the same state, when capturing a certain moment, the density / velocity distributions do not overlap. Collide with. Although airflow noise is generated at the time of a collision, the timing of the collision is shifted, so that the generation timing of the noise is also shifted and the noise generation is not concentrated, and the generated noise can be reduced.

  Thus, according to this Embodiment, since generation | occurrence | production of the noise generate | occur | produced by an airflow can be reduced, the low-noise electric blower 1 is realizable.

  As described above, the electric blower according to the present invention and the electric vacuum cleaner using the electric blower can reduce the noise of the electric blower and the noise of the electric vacuum cleaner.

Half sectional view of the electric blower in the first embodiment of the present invention Top view of the fan part of the electric blower Half sectional view showing a conventional electric blower

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric blower 2 Stator 5 Rotor 6 Shaft 11 Load side bracket 12 Anti-load side bracket 15 Motor 16 Impeller 17 Air guide 18 Fan case 19 Exhaust port 20 Ventilation path 21 Flow change part 22 Return path 24 Intake port 25 Opening part 26 Stator blade

Claims (4)

A motor having a rotor rotatably held by a load side bracket and an anti-load side bracket, an impeller attached to a shaft which is an output shaft of the rotor and having blades, and a stationary blade located on an outer peripheral portion of the impeller An air guide that forms a plurality of ventilation paths, and a fan case that covers the air guide and the impeller, and a plurality of openings that discharge exhaust air from the impeller on the outer periphery of the fan case. The electric blower is characterized in that a and c have a prime relationship with each other, where a is the number of blades of the impeller and c is the number of openings in the fan case. A motor having a rotor rotatably held by a load side bracket and an anti-load side bracket, an impeller attached to a shaft which is an output shaft of the rotor and having blades, and a stationary blade located on an outer peripheral portion of the impeller An air guide that forms a plurality of ventilation paths, and a fan case that covers the air guide and the impeller, and a plurality of openings that discharge exhaust air from the impeller on the outer periphery of the fan case. The electric blower is characterized in that b and c have a prime relationship with each other, where b is the number of ventilation paths of the air guide and c is the number of openings of the fan case. A motor having a rotor rotatably held by a load side bracket and an anti-load side bracket, an impeller attached to a shaft which is an output shaft of the rotor and having blades, and a stationary blade located on an outer peripheral portion of the impeller An air guide that forms a plurality of ventilation paths, and a fan case that covers the air guide and the impeller, and a plurality of openings that discharge exhaust air from the impeller on the outer periphery of the fan case. Provided that the number of blades of the impeller is a, the number of ventilation passages of the air guide is b, and the number of openings of the fan case is c, a, b and c are in a prime relationship with each other. Electric blower characterized by. The vacuum cleaner provided with the dust collection chamber which collects dust, and the electric blower of any one of Claims 1-3.

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