JP5012096B2 - Electric blower and electric vacuum cleaner using the same - Google Patents

Description

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

  There exists a thing like patent document 1 as an electric blower used for the conventional vacuum cleaner. This type of electric blower 19 has a structure as shown in FIG. 10, and includes a fan unit 31 and a motor unit 32. The armature 51 of the motor unit 32 includes a commutator 52 and an armature winding 22, and the armature winding 22 is wound around the outer periphery of the armature core 70. In the armature 51, the bearing 4 is press-fitted into both ends of the motor shaft 53, and the bearing 4 is supported by the load side bracket 5 and the anti-load side bracket 6. The metal brush holder 7 contains a carbon brush 8 and is held by the anti-load side bracket 6. The field winding 23 is wound around the outer periphery of the field core 72.

  The air guide 10 of the fan unit 31 is formed between the load-side bracket 5 and an impeller 11 which is a load and generates suction air or blowing air, and the upper portion of the impeller 11 is covered with a casing 12. The impeller 11 has a plurality of blades 83, is fixed to the shaft 53 by the washer 14 and the nut 15, and rotates together with the shaft 53 of the armature 51.

  The air guide 10 is fixed to the load side bracket 5, and the load side bracket 5 and the anti-load side bracket 6 are also fixed by screws (not shown) or the like. The resin-made tight cap 16 forms an air inlet of the casing 12 and is fixed to the central portion of the casing 12 by welding or the like. The suction port of the impeller 11 and the tight cap 16 come into contact with each other, so that the tight cap 16 is tight. The sex is secured.

  The electric blower 19 is configured in such a structure, and as a function, the blown air generated by the rotation of the impeller 11 passes through the air guide 10 for rectification provided on the outer periphery of the blower outlet 40 of the impeller 11. Thereafter, the armature 51 and the field winding 23 of the motor unit 32 are cooled, passed through the anti-load side bracket 6 and exhausted rearward.

And the vacuum cleaner incorporating this electric blower 19 had a structure as shown in FIG. An electric vacuum cleaner main body 61 (hereinafter referred to as a main body) is divided into a dust collection chamber 81 and a motor chamber 82 by a lattice partition wall 53 provided at the center, and the dust collection chamber 81 has a paper bag 54, a motor. The electric chamber 19 is provided with the electric blower 19. A connection pipe 60, a hose 59, a tip pipe 58, an extension pipe 57, and a nozzle 56 are connected to the main body 61. Then, the electric blower 19 generates suction air, and the dust collected from the nozzle 56 by the suction force of the electric blower 19 passes through the extension pipe 57, the tip pipe 58, the hose 59, and the connection pipe 60 in order, and collects dust. Collected in a paper bag 54 in the chamber 81.
Japanese Unexamined Patent Publication No. 7-63195

  In the conventional electric blower 19, the impeller is rotated at a high speed in order to generate a high suction force. Therefore, the wind noise of the impeller has become a harsh sound with a high frequency. This harsh sound often falls in the frequency range of 3 to 5 KHz, and it has been a problem that it is the most harsh frequency range for humans.

  An object of the present invention is to solve the above-mentioned problem, and to provide an electric blower that reduces the frequency of the annoying noise by shifting the frequency of the annoying noise generated from the electric blower to a high frequency region and an electric vacuum cleaner using the electric blower. And

In order to solve the conventional problems, an electric blower of the present invention includes an armature having an armature winding, a shaft, and a commutator, a plurality of blades fixed to one end of the armature, The impeller is provided with an impeller provided with a blowout port for air blowing, an air guide for rectifying blown air from the blowout port of the impeller, and a casing that covers the outer periphery of the impeller and the air guide. The shape of the outermost peripheral edge of the blade has a multi-step staircase shape, and the blade side surface shape along the rotational side surface from the outermost peripheral edge forming the staircase shape gradually changes toward the axis center. An inclined surface is provided , and the uppermost end portion of the step shape at the outermost peripheral end portion of the blade is formed to be longer in the height direction parallel to the axis than the end portions of the other steps . As a result, the apparent number of blades can be doubled, the frequency of the annoying noise generated from the electric blower can be doubled, and shifted to the high frequency range.

  The electric blower of the present invention is capable of doubling the apparent number of blades, doubling the frequency of the annoying noise generated from the electric blower and shifting it to a high frequency range, and an electric blower for reducing the annoying noise and the same It is possible to provide an electric vacuum cleaner using the.

A first invention includes an armature having an armature winding, a shaft, and a commutator, an impeller having a plurality of blades fixed to one end of the armature, and provided with a blowout port for air blowing on the outer periphery. And an air guide that rectifies the blown air from the air outlet of the impeller, and a casing that covers the outer periphery of the impeller and the air guide, and the blades that form the impeller have a plurality of outermost end shapes. The blade has a stepped shape, and the blade side surface shape along the side surface in the rotational direction from the outermost peripheral end forming the stepped shape is provided with an inclined surface gradually changing toward the axial center, and the outermost peripheral end of the blade The uppermost end of the staircase shape in the section is an electric blower in which the length in the height direction parallel to the axis is longer than the end of the other steps, so that the apparent number of blades Times To, by doubling the frequency of a jarring noise generated from the electric blower can be shifted to the high frequency range, in which it is possible to provide an electric blower which aimed to reduce the harsh sound.

Further , in the first invention, the uppermost end portion of the step shape at the outermost peripheral end portion of the blade is formed to be longer in the height direction parallel to the axis than the end portions of the other steps. To provide an electric blower that reduces the harsh noise while minimizing the gap between the tip of the blade and the air guide inlet and minimizing the reduction in performance such as the suction work rate. It is something that can be done.

According to a second aspect , in the first aspect, the inclined surface that gradually changes from the outermost peripheral end along the side surface in the rotational direction of the blade is configured such that the inclined surface of each step is substantially parallel. Thus, it is possible to provide an electric blower that is capable of reducing the harsh sound while suppressing the performance deterioration due to the difference in the inclined surface.

According to a third invention, in the first or second invention, a member other than the blade is bonded to the outermost peripheral end portion on the side surface opposite to the rotational direction side surface of the blade, and the outermost peripheral end portion including the member By forming the staircase shape with, it is possible to secure the height of the portion forming the staircase shape and increase the number of inclined surfaces, so the frequency of the annoying noise is shifted to a higher frequency, It is possible to provide an electric blower that further reduces the harsh sound.

According to a fourth aspect of the present invention, there is provided an electric vacuum cleaner including the electric vacuum cleaner according to any one of the first to third aspects of the invention and a dust collecting chamber that collects dust by the suction force of the electric blower. It is possible to reduce the harsh sound of the vacuum cleaner.

(Embodiment)
Hereinafter, an electric blower according to an embodiment of the present invention will be described with reference to the drawings. The same components as those of the conventional technology are denoted by the same reference numerals and description thereof is omitted.

  First, a typical impeller will be described. FIG. 8 is an exploded view of a typical impeller. As shown in FIG. 8, the impeller 11 is arranged around the inducer 87, and a plurality of blades 83 curved in the rotational direction are arranged around it. In this state, the blade 83 and the inducer 87 are sandwiched between the plate 82 and the plate 81 from above and below. The armature shaft 53 is inserted into the central hole 88 of the impeller 11 and fixed with screws.

  The plurality of blades 83, the plate 82, and the plate 81 are manufactured by pressing an aluminum plate or the like, the plurality of blades 83 are sandwiched between the plate 82 and the plate 81, and the caulking portion 84 provided on the blade 83 is a plate 82, after inserting into the insertion hole 85 provided facing the plate 81 and temporarily assembling, the crimping portion 84 is crushed and fixed. Note that the three-dimensional shape inducer 87 disposed in the central portion is for improving the rectification effect in the vicinity of the suction port of the impeller 11, and is not necessarily required.

  FIG. 9 is a top view of a state in which a plurality of blades 83 are arranged on a plate 81. In FIG. 9, the side surface in the rotational direction is the rotational direction indicated by the arrow in FIG. A plurality of blades 83 are arranged on the plate 81 so that 83a is positioned, and rotate in the direction of the arrow in accordance with the rotation of the shaft 53 connected to the armature 51. An intake port (not shown) of the electric blower 19 that takes in outside air is located inside the region where the blade 83 is disposed. When the impeller 11 rotates, the air inside the impeller 11 rotates while being pushed by the rotation of each blade 83, and is pushed out by the centrifugal force in the outer peripheral direction of the plate 81 and the impeller 11, and is blown out from the outlet 40 on the outer periphery. Output as wind. Thereby, the blowing wind in the direction indicated by the arrow W can be generated.

  At this time, a wind noise is generated by the rotation of the impeller 11, and this wind noise becomes a harsh sound for humans. This annoying noise can be calculated by the product (N × Z) of the number (Z) of blades 83 that actually cut the wind and the number of rotations (N) that is the number of times the wind is cut. For example, when the impeller 11 as shown in FIG. 9 rotates at 45000 rpm in the direction of the arrow, the number of blades 83 that actually cut the wind (Z = 6) and the number of times the wind is cut per second. The product of the rotational speed (N = 45000/60) (N × Z = 6 × (45000/60)), and the frequency of the impeller rotational sound is 4.5 KHz.

  The rotating sound having such a frequency hits a frequency band that is very sensitive to human ears and feels harsh on hearing. As a method of avoiding this and increasing the frequency of the rotating sound, a method of increasing the number of blades 83 of the impeller 11 is conceivable. However, if the number of blades 83 is significantly increased, the loss of the fan part increases and the efficiency decreases. Even if the number of blades 83 is increased from nine to nine as in the above-described example shown in FIG. 9, the frequency of the annoying noise is increased to 6.75 KHz. However, at that level, it is still a frequency in the human audible range, and some people feel annoying, so it is not a sufficient measure. Therefore, the inventor has devised a method for increasing the impeller rotation sound without increasing the number of blades.

  Hereinafter, the structure of the blade used by the electric blower according to the embodiment will be described in detail with reference to the drawings.

  FIG. 1 is an enlarged perspective view showing an outermost peripheral end of a blade used in an electric blower according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of an impeller incorporating the blade. FIG. 2A is a partial cross-sectional view in which the outer peripheral portion of the impeller is enlarged, and FIG. 2B is a partial cross-sectional view showing the AA cross section in FIG.

  As shown in FIGS. 1 and 2, two inclined surfaces 89a and 89b are formed on the rotational side surface 83a curved in the rotational direction indicated by the arrow so as to form a step shape at the outermost peripheral end portion 83b of the blade 83. There are three surfaces that cause wind cuts. The leading edge of the end having the thickness of the initial blade 83 is P1, the leading edge of the first inclined surface 89a is P2, and the leading edge by the second inclined surface 89b is P3. The inclined surfaces 89a and 89b up to the points H2 and H3 that recover to their thickness are obtained by crushing the blade 83 made of an aluminum material or the like with a mold.

  Since the frequency of the harsh sound is determined by how many times the wind is cut in a certain time with respect to a certain fixed point, as shown in FIG. 3, by providing a step at the outermost peripheral end 83b of the blade 83, It becomes possible to double the frequency of the harsh sound according to the ratio of increasing the number of leading edges.

  For example, as shown in FIG. 3, the description will be made by paying attention to the outermost peripheral end 83b of one blade 83. When the moment when the edge P1 passes through a certain fixed point is (A), the edge P2 of the next step is set. (B) and the moment when the edge P3 of the next step passes the same fixed point becomes (c). It can be said that the same phenomenon has occurred as the blades are cutting the wind.

  Therefore, the frequency of the annoying noise when the number of surfaces (K) provided at the blade end is three is the number of blades 83 (Z) that actually cut the wind and the number of surfaces provided at the blade end ( K) and the product (N × K × Z) of the number of rotations (N) that is the number of times the wind is cut off. When it is calculated, it becomes (N × K × Z = 6 × 3 × (45000/60), and the frequency of the wind noise is 13.5 KHz. If the frequency exceeds 10 KHz, it will be difficult to hear for ordinary people, and it will feel that the harsh noise is considerably reduced in the human ear, that is, the frequency of the harsh noise generated from the electric blower 19 will be doubled. It is possible to reduce the above sound (harsh sound).

  Next, another embodiment will be described with reference to FIG. FIG. 4 is a diagram showing a cross-section of the main part viewed from the outer peripheral side of the impeller, and shows the length L1 in the height direction that forms the leading edge (the uppermost end in the claims) P1 having the thickness of the blade 83 itself. Length L2 in the height direction that forms the leading edge (the end of the other step in the claims) P2 by the first-stage inclined surface 89a (the other edge in the claims) The end of the step) is set to be longer than the length L3 in the height direction forming P3 (L1> L2, L3). This makes it possible to reduce the harsh sound without significantly reducing the efficiency (suction power) at the fan section. As shown in FIG. 5, the distance between the tip edges P1, P2, and P3 of the blade 83 and the tips E0 of a plurality of guide vanes 90 provided on the air guide 10 for rectification is small. As the gap becomes smaller, generally the efficiency (suction power) of the fan part is improved, and the reduction of the efficiency of the fan part can be prevented by reducing the gap.

  More specifically, when the tip edges P1, P2, and P3 of a blade 83 pass through one guide blade 90, each tip edge P1, P2, and P3 of the blade 83 and the tip of the guide blade 90 are shown. The distances LP1, LP2, and LP3 from the edge E0 are closest to each other in the order of the positions (a), (b), and (c) shown in FIG. As can be seen, the leading edges P2 and P3 of the inclined surfaces 89a and 89b have a longer separation distance to the leading edge E0 of the guide blade 90 than the leading edge P1 having the thickness of the blade 83 itself (LP3>). LP2> LP1). As the separation distance from the tip E0 of the guide vane 90 increases, the loss during rectification increases. Therefore, by increasing the height L1 of the tip edge P1, which is short from the tip E0 of the guide vane 90, the fan portion It becomes possible to suppress a decrease in efficiency.

  FIG. 6 is an enlarged top view of the outermost peripheral end of the blade. As shown in FIG. 6, the inclined surface 89a indicated by P2-H2 and the inclined surface 89b indicated by P3-H3 are made substantially parallel. As a result, it is possible to minimize a decrease in efficiency in the fan unit. If the inclined surfaces 89a and 89b are not substantially parallel, the angles of the inclined surfaces 89a and 89b are different from each other. Therefore, a separation phenomenon may occur in which the air flow cannot follow the movement of the blade 83, or turbulence may occur. As a result, a flow phenomenon may occur, resulting in a decrease in efficiency. Therefore, by making the inclined surface of P2-H2 and the inclined surface of P3-H3 substantially parallel, it is possible to suppress the separation phenomenon and the turbulent flow phenomenon, and to maintain high efficiency in the fan portion.

  Further, as shown in FIG. 7, a chip member 91 made of resin or the like is attached to the inner surface of the outermost peripheral end portion of the blade 83, and a stepped step is provided in the thickness including the chip member 91. Since the number of steps can be increased, the frequency range of the harsh sound can be further moved to the high frequency range.

  Finally, when the electric blower 19 described above is incorporated in the main body 61 shown in FIG. 11, it is possible to mount an electric blower that eliminates the annoying noise, so that the electric noise of the electric vacuum cleaner can be reduced. It becomes possible to plan.

  As described above, the electric blower according to the present invention eliminates the need to take measures to reduce the annoying noise by adding a soundproofing material, etc., so that it is necessary to reduce the size of the product regardless of the floor moving AC cleaner. It can also be used for applications such as molds, vertical types, or DC rechargeable vacuum cleaners.

The expanded perspective view of the outermost periphery edge part of the braid | blade which concerns on one Embodiment of this invention. The expanded partial sectional view of the impeller incorporating the blade (a) The partial sectional view which expanded the outer peripheral part of the impeller, (b) The sectional view which shows the AA section in FIG. 2 (a) Fixed point movement diagram in the enlarged partial sectional view of the impeller (A) A diagram showing the moment when the edge P1 passes through the fixed point, (B) A diagram showing a moment when the edge P2 passes through the fixed point, (C) Edge P3 passes through the fixed point Figure showing the moment Enlarged partial sectional view when L1 of impeller incorporating the blade is provided long Partial enlarged view of the distance between the blade and the guide blade Partial enlarged view when the inclined surface of the blade is substantially parallel Enlarged perspective view of the outermost periphery when a tip is provided at the tip of the blade General impeller assembly parts exploded view Top view of a typical impeller Partial sectional view of an electric blower in a conventional example Cross-sectional view of a conventional vacuum cleaner

DESCRIPTION OF SYMBOLS 10 Air guide 11 Impeller 12 Casing 19 Electric blower 32 Motor part 51 Armature 53 Shaft 81,82 Plate 83 Blade 83a Rotation direction side surface 89a, 89b Inclined surface

Claims (4)

An armature having an armature winding, a shaft, and a commutator; an impeller having a plurality of blades fixed to one end of the armature and provided with a blowout port for air blowout on an outer periphery; and a blowout of the impeller An air guide for rectifying the blown air from the mouth, and a casing for covering the outer periphery of the impeller and the air guide, and the shape of the outermost peripheral end of the blade forming the impeller has a multi-step staircase shape. The blade side surface shape along the side surface in the rotational direction from the outermost peripheral end portion forming the staircase shape is provided with an inclined surface gradually changing toward the axial center, and the stepped shape at the outermost peripheral end portion of the blade is provided . The uppermost end is an electric blower formed by forming a length in the height direction that is parallel to the axis longer than the end of the other steps . Inclined surface formed gradually changing to along the outermost end in the rotational direction side of the blade is electric blower according to claim 1, the inclined surface of each stage is configured substantially in parallel. The blade rotation direction side of bonding a separate member from the blade to the outermost peripheral edge portion of the opposite side, according to claim 1 or 2 by forming a step shape at the outermost peripheral edge portion, including the member Electric blower. The electric vacuum cleaner provided with the electric blower of any one of Claims 1-3 , and the dust collection chamber which collects dust with the attraction | suction force of the said electric blower.

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