JP2013072360A - Electric air blower and vacuum cleaner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly efficient electric air blower by improving reliability by reducing the axial run-out, vibration and noise of an impeller when rotating the impeller at a high speed.SOLUTION: A rotary shaft 2 is provided with the impeller 12 having a front shroud 12b and a rear shroud 12a, a blade 12c sandwiched between the pair of shrouds and an inducer 12d joined to the suction port side of the blade 12c and sandwiched between the pair of shrouds. The impeller 12 is provided with a cylindrical spacer 12e for fixing the rotary shaft 2 in a hub 12f for constituting a base of the inducer 12d. The cylindrical spacer 12e can prevent the co-rotation of the impeller 12 by being penetratingly arranged in the rear shroud 12a, and arranging at least one plane opposed to the rotary shaft 2, can cope with abrupt acceleration-deceleration operation, and the axial run-out of the impeller 12 is restrained. Thus, the vibration and noise of the electric air blower are reduced to improve reliability.

Description

  The present invention relates to a highly efficient electric blower that uses a simple structure and construction method to suppress impeller axial blurring and reduce vibration noise.

  Conventionally, this type of electric blower has been widely used in household vacuum cleaners. The vacuum cleaner is desired to have a strong suction force, and in order to obtain a stronger suction force, it is necessary to improve the blowing performance of the electric blower of the vacuum cleaner. In order to improve the blowing performance of the electric blower, it is desired to improve the fan efficiency as well as increase the fan output in the fan section of the electric blower. In order to improve fan efficiency, in addition to design items for fan development (diameter increase etc.), to reduce disk friction loss due to small fan diameter, efficiency improvement by high-speed fan rotation is also included in the design items. It is essential as a development item.

The electric blower is mainly composed of five parts as shown below.
Impeller parts that generate air volume and pressure (dynamic pressure and static pressure) by rotating at high speed, and air guide parts that convert the dynamic pressure generated by the impeller to static pressure and contribute to fan efficiency (so-called A diffuser guide), and a fan case of an outer part that covers the impeller and the air guide, does not leak inside air, and prevents outside air from entering, and has a rotating shaft that is rotated by electricity A motor unit composed of a rotor and a stator,
It is mainly composed of five points: a bearing portion that supports both ends of the rotating shaft, and a frame that holds the bearing and covers the bearing and the stator.

  The impeller is assembled and configured by a plurality of parts, and includes a front shroud and a rear shroud having a suction port in the center, a blade narrowed between a pair of shrouds, and a suction port side of the blade, and a front shroud and It has an inducer that is pressed down from the front and rear by a rear shroud, and has a cylindrical spacer that fixes a rotating shaft inside a hub that constitutes the base of the inducer.

  Since the impeller part increases the load on the impeller as the number of rotations increases, the impeller part may be replaced with other parts (air guide or fan case) due to the impeller structure (strength, material, structure) or poor assembly during assembly. ) Due to damage or insufficient impeller strength, the centrifugal force increases due to increased rotation speed, and the impeller is deformed due to increased pressure applied to the impeller due to increased fan output. .

  As described above, the impeller portion of the fan portion of the electric blower is an important component for fan performance that generates air volume and pressure, and is also an important component for securing the reliability of the fan. Therefore, conventionally, various techniques have been developed to improve the performance and reliability of the impeller unit.

For example, in order to improve the performance and reliability of the impeller part, there is a configuration having the following configuration.
In the conventional technology, by making the inner diameter of the cylindrical spacer inserted into the inducer larger than the diameter of the motor shaft insertion hole provided in the rear shroud, the coaxiality and perpendicularity between the impeller and the motor shaft can be adjusted with the rear shroud. To keep.

At this time, the inner diameter of the cylindrical spacer is not in contact with the motor shaft, and is a clearance fit hole. The hole accuracy of the rear shroud can suppress the shaft center blur of the impeller, reduce vibration and noise, and provide a highly efficient electric blower (see, for example, Patent Document 1).

  8-10, FIG. 8 is sectional drawing of the conventional electric blower described in the said patent document 1, FIG. 9 is the impeller expanded sectional view of the electric blower, FIG. 10 used the electric blower. It is a schematic block diagram of the conventional vacuum cleaner. In FIG. 8, this type of conventional electric blower 51 includes a motor unit 53 and a fan unit 52. A rotor 38 of the motor unit 53 includes a commutator and a rotor winding. At 38, the rotor winding is wound around the outer periphery of the armature core. In the rotor 38, bearings 40 are press-fitted into both ends of the rotating shaft 37 of the motor portion 53, and the bearings 40 are supported by the fan side frame 54 and the anti-fan side frame 55. The stator 39 includes windings, and the non-fan side frame 55 that holds the bearing 40 that includes the stator 39 and supports the rotating shaft 37.

  In this electric blower, the air guide 44 of the fan unit 52 is a rectifying air guide 44 formed between the fan-side frame 54 and an impeller 43 for air suction and blowing as a load, and above the impeller 43. Is covered with a fan case 46.

  The impeller 43 assembled by press parts such as aluminum has a plurality of blades 42 sandwiched between a rear shroud 42b having a flat disk shape and a front shroud 42a having an umbrella disk shape, and sintered. A spacer 57 made of brass or brass, a washer 56 made of sheet metal or the like, and a nut 58 are fixed to the rotating shaft 37 and rotate together with the rotating shaft 37.

  The air guide 44 is fixed to the fan side frame 54 with screws (not shown) or the like, and the fan side frame 54 and the non-fan side frame 55 are also fixed with screws (not shown) or the like.

  Next, the structure of the impeller part of the said electric blower is demonstrated using FIG. In FIG. 9, the impeller 43 is attached to the rotary shaft 37, and only the portion above the bearing 40 is shown. The height of the cylindrical spacer 59 is set equal to or slightly higher than the height of the hub 42d, and the inner diameter of the cylindrical spacer 59 is set slightly larger than that of the center hole 49 of the rear shroud.

  The cylindrical spacer 59 is provided with a gap 47 in the radial direction with respect to the hub 42d. In the impeller 43 constituting this conventional embodiment, the inducer 42c and the hub 42d are made of resin, and the front shroud 42a, the rear shroud 42b and the blade 42 are made of sheet metal. The operation of the above configuration is as follows.

  A washer 56 and an impeller 43 are sequentially inserted on the spacer 57 inserted into the rotating shaft 37, and then a cylindrical spacer 59 is inserted and fastened by a nut 58. When the impeller 43 is inserted, the position with respect to the rotary shaft 37 is determined by the center hole 49 provided in the rear shroud 42b.

  Thereafter, a cylindrical spacer 59 is inserted and fastened with a nut 58. The cylindrical spacer 59 has gaps 47 and 48 with respect to both the hub 42d of the inducer 42c and the rotary shaft 37, and it is assumed that resin Even if the made inducer 42c is attached to the impeller 43 with deformation, the cylindrical spacer 59 can maintain parallelism with the rotary shaft 37, and even when finally tightened with the nut 58, The impeller 43 can be mounted perpendicular to the rotating shaft 37.

  Further, even if heat generated from the armature (not shown) of the motor is transmitted to the rotating shaft 37 by the gaps 47 and 48, it is not directly transmitted to the resin hub 42d, so that the creep of the resin inducer 42c is performed. (Deformation) can be suppressed.

  Further, since the impeller 43 is sandwiched between the lower spacer 57, the washer 56, the cylindrical spacer 59, and the nut 58, the nut 58 is hardly loosened, and the phase shift of the impeller 43 can be prevented.

  As described above, in the electric blower 51 using the conventional impeller 43, the gap 48 is intentionally provided between the cylindrical spacer 59 and the rotating shaft 37, and the impeller 43 is fixed by the clamping force between the nut 58 and the rear shroud 42b. By adopting such a configuration, the verticality of the impeller 43 with respect to the rotation shaft 37 is maintained, and a mounting configuration with a good balance and less vibration can be realized.

  The vacuum cleaner incorporating the above-described conventional electric blower 51 has a structure as shown in FIG. In FIG. 10, a vacuum cleaner main body 61 (hereinafter referred to as “main body 61”) is divided into a dust collection chamber 63 and a motor chamber 64 by a lattice partition wall 62 provided at the center. The dust chamber 63 is provided with a paper bag 65, and the motor chamber 64 is provided with the electric blower 51. A connection pipe 66, a hose 67, a tip pipe 68, an extension pipe 69, and a nozzle 70 are sequentially connected to the main body 61.

  As an action of the conventional vacuum cleaner, dust collected from the nozzle 70 by the suction force of the electric blower 51 passes through the extension pipe 69, the tip pipe 68, the hose 67, and the connection pipe 66, and the dust collection chamber 63. In a paper bag 65.

In addition, there are some which improve the axial accuracy of the impeller and improve the performance of the impeller and have the following configuration.
In the prior art, a rib provided on the bottom surface of the inducer and a groove arranged in the rear shroud prevent air leakage between the rear shroud and the inducer, and constitute a highly efficient electric blower (for example, Patent Document 2).

  FIG. 11 is a partially enlarged cross-sectional view of an impeller portion of a conventional electric blower described in Patent Document 2. In FIG. 11, a plurality of circumferential ribs 100 provided on the bottom surface of the inducer 201 and a plurality of circumferential recesses 101 provided on the inner surface of the rear shroud 200 so as to face the circumferential rib 100 are fitted. Then, due to the labyrinth effect, the air from the rear shroud 200 side is surely sealed, and the gap between the shaft hole 80 and the shaft 130 generated during assembly passes through the gap between the rear shroud 200 and the inducer 201. The air can be prevented from flowing into the centrifugal impeller 110.

Japanese Patent Laid-Open No. 2000-136895 JP 2001-132686 A

  However, in the configuration of the above-mentioned conventional Patent Document 1, the cylindrical spacer inserted inside the inducer does not project the motor shaft, but the motor shaft is centered by the rear shroud hole. Since the thickness is smaller than the overall height of the impeller, the contact with the motor shaft is only the hole of the rear shroud.

  The electric blower normally used for an electric vacuum cleaner is operated at a high speed rotation of 30000 to 45000 r / min. As the motor rotates, the outer periphery of the impeller moves forward and backward around the motor shaft in the motor shaft direction. There is a possibility of causing a phenomenon of surface runout that causes vibration. This becomes noise and is one of the factors that increase fan noise.

  Further, in an ordinary electric blower, the impeller portion, the fan case, and the air guide are designed with a minute clearance for high efficiency. When the longitudinal vibration of the outer periphery of the impeller becomes excessively large, there is a possibility of damage due to contact of the outer periphery of the impeller with the fan case or the air guide. Further, when the fan is further rotated at a higher speed, for example, 45,000 to 120,000 r / min, in order to obtain a further increase in output, the surface vibration of the impeller further increases, and the fan There was a problem that the reliability of the part also increased.

  Further, in the configuration of the above-mentioned conventional patent document 2, in the configuration in which the air leakage is prevented by the groove arranged on the inducer bottom surface rib and the rear surface shroud, the inducer is positioned by the bottom surface rib and the rear surface shroud groove. In order to carry out, detailed processing is required for the positional accuracy of the shroud grooves and ribs, and thus there is a problem that the processing accuracy is difficult. In addition, there is a problem of increasing the processing cost due to difficult processing.

The present invention solves the above-mentioned conventional problems, and improves the reliability of the impeller by reducing the vibration and noise of the electric blower and improving the reliability by improving the accuracy of shaft alignment.
Further, by improving the accuracy of the shaft core, it is possible to reduce the clearance between the outer periphery of the impeller and the air guide, and to provide a highly efficient electric blower that reduces the leakage of the impeller and the air guide. It is another object of the present invention to provide a highly efficient electric blower that uses a simple structure and construction method to suppress impeller shaft blurring and reduce vibration and noise.

  In order to solve the above-described conventional problems, an electric blower of the present invention holds a motor in which a rotor having a rotating shaft and a stator are arranged to face each other, a bearing that supports at least one end of the rotating shaft, and the bearing A frame covering the stator, a front shroud fixed to the end of the rotating shaft and having a suction port in the center, a rear shroud facing the front shroud, a plurality of blades, and the suction port of the blade And an impeller configured such that an inducer joined to the side is sandwiched between the pair of shrouds, and the impeller has a cylinder for fixing the rotating shaft inside a hub constituting a base portion of the inducer. And the cylindrical spacer is disposed through the rear shroud, and the cylindrical spacer and the rotating shaft have at least one surface facing each other. One in which was placed Te.

  As a result, the impeller and the rotating shaft of the motor can contact not only the conventional contact point due to the thickness of the rear shroud but also the inner cylindrical portion of the cylindrical spacer, and the contact area between the rotating shaft and the impeller can be increased. .

  When the impeller is operated at a high speed of 30000 to 45000 r / min, the outer periphery of the impeller causes a phenomenon of surface vibration that causes vibration in the front and rear directions around the impeller fixing portion of the rotating shaft in the motor shaft direction. The reason for increasing the noise is that since the impeller contacts the cylindrical portion of the cylindrical spacer, the accuracy of the coaxiality between the impeller and the rotating shaft is improved.

  In addition, the end surface of the cylindrical spacer and the rotating shaft are conventionally made from a sheet metal press because the rear surface shroud is difficult to cut and polish because the rear surface shroud is made of a thin plate for cost reduction and production cycle improvement. It is often produced by punching with products, and because the material shape is as it is, the part size is larger in the radial direction compared to the cylindrical spacer, so the surface shape of relatively flatness and parallelism is distorted. There is something. By contacting the rotating shaft with such a rear surface shroud, the rotating shaft and the impeller may decrease in perpendicularity even if the hole accuracy of the rear surface shroud is improved.

Compared with the rear surface shroud, the end surface portion of the cylindrical spacer that is small in size in the radial direction has good flatness and parallelism, and the inner diameter cylindrical portion has good degree of perpendicularity to the end surface portion. Therefore, by contacting the inner diameter cylindrical portion of the cylindrical spacer and the rotation shaft, the accuracy of the impeller can be improved, and the accuracy of the perpendicularity between the impeller and the rotation shaft can be improved.

  Impellers with improved concentricity and verticality are designed with a small clearance for the impeller part, fan case, and air guide in order to improve the efficiency of ordinary electric blowers. It is possible to reduce the possibility of damage due to contact with the fan case and the air guide on the outer periphery of the impeller.

  In addition, even when the fan is further rotated at a higher speed, for example, 45,000 to 120,000 r / min, in order to obtain a further increase in output, the coaxiality and cylindricity of the impeller are improved. It is possible to reduce the problem that the impeller's surface runout is reduced and the reliability of the fan portion is lowered.

In addition, the cylindrical spacer is disposed through the rear shroud, and by arranging and configuring a surface that faces at least one surface of the rotating shaft, the impeller and the rotating shaft can be fixed by surface contact.
It is possible to prevent the impeller and the rotating shaft from rotating together.

  By arranging the opposing surfaces, it is possible to transmit the torque generated by the motor unit and the rotating shaft to the impeller without waste, and it is possible to cope with various operating conditions. For example, an electric blower operated at high speed is subjected to operation control such as rapid acceleration and rapid deceleration. By making surface contact with the opposing surfaces, the impeller can instantaneously synchronize with the movement of the rotating shaft for rapid acceleration or deceleration by surface contact. Therefore, it becomes an electric blower capable of various operating conditions.

  Further, by improving the accuracy of the coaxiality and squareness between the impeller and the rotating shaft, the clearance between the outer periphery of the impeller and the air guide can be reduced, and the leakage of the recirculation between the impeller and the air guide can be reduced.

  Also, the improvement in accuracy over the past means that leaks between the impeller and the air guide, known as recirculation loss, have been a cause of fan performance degradation. Impeller mounting accuracy, which has been considered difficult, can be reduced, and impeller surface run-out can be reduced by improving the accuracy of coaxiality and perpendicularity between the impeller and rotating shaft, and the clearance between the impeller and air guide is also reduced. An efficient electric blower can be provided.

  In the electric blower of the present invention, the impeller rear shroud and the cylindrical spacer are configured to penetrate through a substantially rectangular hole so that the impeller and the rotating shaft can be prevented from rotating, and the motor torque is not wasted even during acceleration / deceleration operation. Therefore, it is possible to provide an electric blower that prevents deterioration in reliability and performance efficiency. Moreover, by suppressing the shaft center blur of the impeller, the vibration and noise of the electric blower can be reduced and the reliability can be improved. Furthermore, by reducing the shaft center blur, it is possible to reduce the clearance between the outer periphery of the impeller and the air guide, and it is possible to provide a high-efficiency electric blower with reduced leakage of the impeller and the air guide.

Sectional drawing of the electric blower in Embodiment 1 of this invention Same as above, sectional view of impeller part of electric blower Same as above, rear view of impeller part of electric blower The rear view of the impeller part which comprised multiple surfaces in the cylindrical spacer of the impeller part of the electric blower The longitudinal cross-sectional view which shows the main body structure of the vacuum cleaner using an electric blower The rear view of the impeller part which provided the key coupling of the electric blower in Embodiment 2 of this invention Same as above, rear view of impeller portion provided with a plurality of key joints of electric blower Sectional drawing of the electric blower of the conventional patent document 1 Same as above, sectional view of impeller part of electric blower The schematic block diagram which shows the main body structure of the vacuum cleaner using an electric blower Partial enlarged view of the impeller portion of the conventional electric blower of Patent Document 2

  1st invention hold | maintains the motor which arranged the rotor and stator which have a rotating shaft facing each other, the bearing which supports at least one end of the said rotating shaft, the frame which covers the said bearing and the said stator, and the said rotation A front shroud fixed to the end of the shaft and having a suction port in the center, a rear shroud facing the front shroud, a plurality of blades and an inducer joined to the suction port side of the blade An impeller configured to be sandwiched between a pair of shrouds, and the impeller includes a cylindrical spacer that fixes the rotating shaft inside a hub that forms a base of the inducer. The cylindrical spacer and the rotating shaft are disposed so as to have at least one surface facing each other.

  As a result, the coaxiality and squareness, which are the mounting accuracy of the impeller and the rotating shaft, can be improved with a simple structure and configuration, and it is possible to reduce surface runout due to the high speed rotation of the impeller, and vibration and noise of the electric blower To improve product reliability. Further, the clearance between the outer periphery of the impeller and the air guide can be reduced, the leakage of the recirculation between the impeller and the air guide can be reduced, and the fan efficiency can be improved.

  Further, by controlling the impeller run-out, the impeller can be rotated or rotated from 30000 to 45000 r / min, even at high speeds of 45,000 to 120,000 r / min. The fan output can be improved by high-speed operation.

  In addition, the cylindrical spacer is disposed through the rear shroud, and by arranging and configuring a surface that faces at least one surface of the rotating shaft, the impeller and the rotating shaft can be fixed by surface contact, and the impeller and the rotating shaft can be fixed. Co-rotation can be prevented. By arranging the opposing surfaces, it is possible to transmit the torque generated by the motor unit and the rotating shaft to the impeller without waste, and it is possible to cope with various operating conditions. For example, an electric blower operated at high speed is subjected to operation control such as rapid acceleration and rapid deceleration. By making surface contact with the opposing surfaces, the impeller can be instantaneously synchronized with the movement of the rotating shaft for rapid acceleration or rapid deceleration by surface contact. Therefore, it becomes an electric blower capable of various operating conditions.

  In the second invention, in particular, the cylindrical spacer and the rotating shaft of the first invention are arranged through a plurality of opposing surfaces, so that the contact area between the cylindrical spacer and the rotating shaft is one surface. Compared with the case where the two are opposed to each other, the number of surfaces receiving a load due to high-speed rotation increases because of the plurality of surfaces, and the mounting strength and stability of the impeller can be increased. It is possible to prevent an increase in sliding loss due to co-rotation of the impeller and the rotating shaft.

According to a third aspect of the present invention, there is provided a motor in which a rotor having a rotating shaft and a stator are arranged to face each other, a bearing that supports at least one end of the rotating shaft, a frame that covers the bearing and the stator, and the rotation A front shroud fixed to the end of the shaft and having a suction port in the center, a rear shroud facing the front shroud, a plurality of blades and an inducer joined to the suction port side of the blade An impeller configured to be sandwiched between a pair of shrouds, and the impeller includes a cylindrical spacer that fixes the rotating shaft inside a hub that forms a base of the inducer. The cylindrical spacer and the rotating shaft are disposed so as to have at least one key joint that is fitted to each other.

  This is a structural element for mechanically coupling the cylindrical spacer of the impeller and the rotary shaft, and the rotational force is accurately transmitted to the cylindrical spacer of the impeller using the key of the rotary shaft as a medium. And the rotation axis can be prevented from co-rotating, so that various operating conditions can be accommodated.

  For example, an electric blower operated at high speed is subjected to operation control such as rapid acceleration and rapid deceleration. If the impeller has no medium that accurately transmits the rotational force of the rotating shaft due to acceleration / deceleration operations such as rapid acceleration or rapid deceleration, the impeller rotates together and cannot respond instantaneously. However, the key joint allows the impeller to instantaneously synchronize the movement of the rapid acceleration and deceleration shafts using the key joint as a medium to transmit the rotational force to the impeller. Therefore, the impeller cylindrical spacer and the rotation shaft can be prevented from rotating, and an increase in sliding loss due to the joint rotation of the impeller cylindrical spacer and the rotation shaft can be prevented, and an electric blower that can cope with various operating conditions. It becomes.

  In addition, by transmitting the rotational force of the rotating shaft accurately to the impeller using the key joint as a medium, the impeller rotates stably in synchronization with the rotating shaft, resulting in an electric blower with reduced vibration and noise. Product reliability can be improved.

  In a fourth aspect of the invention, in particular, in the third aspect of the invention, the cylindrical spacer and the rotating shaft are mechanically coupled to the cylindrical spacer of the impeller and the rotating shaft by being configured by a plurality of key joints. The key joint, which is a structural element for this purpose, serves as the medium, and multiple key joints can accurately transmit the rotational force to the cylindrical spacer of the impeller. Impeller mounting strength and stability can be increased. Therefore, it is possible to further prevent an increase in sliding loss due to the simultaneous rotation of the impeller and the rotating shaft, and it is possible to cope with various operating conditions.

  In particular, the fifth aspect of the invention is a vacuum cleaner equipped with the electric blower of any one of the first to fourth aspects of the invention, so that it has a strong suction force, good dust removal, and the bearing reliability of the electric blower. It becomes a vacuum cleaner with improved performance.

  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)
FIGS. 1-5 shows the structure of the electric blower in the 1st Embodiment of this invention. 1 is a partial cross-sectional view of the electric blower, and FIG. 2 is an enlarged view of an impeller portion of the electric blower. 3 is a rear view of the impeller portion of the electric blower, and FIG. 4 is a rear view in which a plurality of surfaces are provided on the cylindrical spacer of the impeller portion of the electric blower. FIG. 5 is a longitudinal sectional view showing a schematic configuration of the main body of the electric vacuum cleaner.

As shown in FIGS. 1 to 5, the electric blower 1 a includes a rotor 3 having a rotating shaft 2 and a fixed core 5 a that is arranged with a gap around the outer periphery of the rotor 3 and wound with a winding 4. A front frame located on the suction side that holds the stator 6 and holds the bearing 9 of the rotary shaft 2 and a plurality of second guide vanes 8a that are fitted and fixed with grooves 7a on the outer periphery of the core 6a and the core 5a The impeller 12 fixed to the motor 10a and the rear frame 10b positioned in the discharge direction and the rotary shaft 2 and assembled by an inducer 12d of a press part such as aluminum or a resin part, and the impeller 12 are covered. The fan case 13 and a motor case 15 that is disposed in contact with the front frame 10a and forms a plurality of first independent air passages 16 are configured.

  Further, the impeller 12 is fixed to the rotary shaft 2 by a collar (washer) 30 made of sheet metal or the like and a nut, and a front shroud 12b made of an umbrella-shaped disk shape having an air inlet at the center and a flat disk. A rear shroud 12a having a shape sandwiches and supports a blade 12c that sucks air from the center and blows air to the outer periphery, and a resin inducer 12d.

  FIG. 2 is an enlarged view of the impeller 12 when the electric blower is attached. FIG. 3 is a rear view of the impeller 12 part, and is a view showing a cylindrical spacer 12e penetrating through the rear shroud 12a.

  The impeller 12 sucks air from the central portion by an umbrella-shaped disc-shaped front shroud 12b and a flat disc-shaped rear shroud 12a, which are manufactured by an aluminum sheet metal press or the like and have a suction port in the center. A plurality of blades 12c manufactured by an inducer 12d formed of resin or the like that blows air to the outer peripheral portion and an aluminum sheet metal or iron metal sheet metal press are sandwiched and supported.

  The nipped blade 12c is fitted into the claw portion provided in the blade 12c and the hole shape provided in the front shroud 12b and the rear shroud 12a, and is fastened by so-called caulking. Accordingly, the front shroud 12b, the rear shroud 12a, and the blade 12c are fastened by caulking.

  The inducer 12d is located on the extension of the blade 12c and is composed of a three-dimensional curved surface and a hub 12f for blowing air from the center to the outer periphery. The impeller 12 is fixed to the rotating shaft 2 of the electric blower 1a. In order to prevent the inducer 12d from creeping under the influence of the tightening pressure of the nut 33, a metal cylindrical spacer 12e having a higher rigidity than the resin is inserted.

  The cylindrical spacer 12e and the inducer 12d are bonded using an elastic adhesive, or bonded and fixed using a resin adhesive or a cured resin and various adhesives. In the present embodiment, the description is made using the adhesive fixing, but the present invention is not limited to the adhesive fixing or the adhesive, but the inducer 12d manufactured from a resin material or the like and a metal material. Utilizing the difference in thermal expansion coefficient with the manufactured cylindrical spacer 12e, the metal material has a high thermal expansion coefficient at the same temperature, so that the press-fitted state can always be maintained and fixed to the inducer 12d. .

  Also, by installing a cylindrical spacer mainly made of a metal material during the press-fitting, shrink-fitting, or molding process, the cylindrical spacer can also be installed inside during the inducer molding. It may be formed, and the inducer 12d and the cylindrical spacer 12e may be fixed to prevent co-rotation. Even if they are fixed using other methods, the effect of the present invention does not change.

The end surface portion of the cylindrical spacer 12e protrudes from the end surface portion of the hub 12f toward the rear surface shroud 12a and is disposed so as to penetrate the rear surface shroud 12a. The inducer 12d uses a contact portion between the blade 12c and the three-dimensional curved surface of the inducer 12d to form a claw-shaped connecting portion that serves as a detent, and is positioned, and the front shroud 12b and the rear shroud 1 are positioned.
It is sandwiched and supported by 2a.

  The impeller 12 is fastened by a nut 33 with a cylindrical spacer 12 e inserted into the rotary shaft 2. Among them, a plate-like spacer 32 is arranged on the rear shroud 12 a located on the bottom surface of the impeller 12, and a cylindrical collar 30 is arranged on the front frame 10 a side which is the rear portion of the plate-like spacer 32. The rotary shaft 2 includes a cylindrical collar 30, a plate-like spacer 32, and an impeller 12 in order from the bearing 9 on the frame front side 10 a, and is fastened to the rotary shaft 2 by a nut 33.

  The cylindrical spacer 12e has an outer diameter portion formed in a cylindrical shape, and is fixed to the inducer 12d as described above. The part combined with a part of the rotating shaft 2 on the rear surface shroud 12a side of the inner diameter portion of the cylindrical spacer 12e is configured and arranged with at least one surface facing. This is a so-called D-cut surface 12g, and the rotary shaft 2 and the cylindrical spacer 12e are in surface contact with each other by the D-cut surface 12g and are arranged. Thereafter, as described above, the rotary shaft 2 is fastened by the nut 33 from the front shroud 12b side.

  As for the bearing 9 of the rotating shaft 2, the outer ring 9b fixedly disposed on the front frame 10a, the inner ring 9c fixedly disposed on the rotating shaft 2 and rotated together with the rotor 3 and the impeller 12, and the rotational load from the rotating shaft 2 were received. This is a so-called rolling bearing constituted by a retainer (not shown) that holds the ball portion 9a between the outer ring 9b and the inner ring 9c, with the ball portions 9a to be connected to the inner ring 9c and the ball portions 9a arranged at equal positional intervals.

  The bearing 9 incorporates lubricating grease (not shown), and seal plates 9d that prevent the lubricating grease from leaking and prevent dust and foreign matter from entering from the outside of the bearing are arranged vertically. The upper and lower seal plates 9d are fixed to the outer ring 9b, and the bearing 9 having a so-called non-contact seal configuration in which no contact is made with the inner ring 9c is arranged. A collar 30 made of sintered or brass is formed on the bottom surface of the spacer 32, and the impeller 12 is fixed to the rotary shaft 2 by a nut 33 via the spacer 32 and the collar 30.

  The spacer 32, the collar 30, and the cylindrical spacer 12e are made of metal such as aluminum, iron, a sintered alloy, or brass. Other resin materials such as polyphenylene sulfide (PPS), polybutylene terephthalate (PBS), polyoxymethylene (POM), polyamide (PA), and other thermoplastic resin materials and thermosetting resins are also rigid resins. Any material may be used. Similarly, a metal material may be made of a resin material or a metal material having good wear resistance and slidability, and a material that can withstand the rigidity of the clamping pressure when fastened to the nut 33. The effect according to the present invention is not changed, and the present invention is not limited to this.

  Since the spacer 32, the collar 30, and the cylindrical spacer 12e are important parts that determine the assembly accuracy of the impeller 12 and the electric blower, as in the past, sheet metal pressing, cutting, polishing, molding, casting, casting, rolling Any effect may be obtained as long as it is manufactured by various processing methods and has a precise processing accuracy equivalent to that of the prior art.

  The inner diameter hole tolerance of the rotary shaft 2 and the cylindrical spacer is as tight as possible in terms of assembly and processing. Conventionally, since the rotation shaft 37 and the rear surface shroud 42b have determined the geometrical tolerance in assembly such as the coaxiality, perpendicularity, flatness, parallelism, etc. of the impeller 12 due to the hole tolerance, the rear surface shroud 42b and the rotation shaft 2 are The geometric tolerance was suppressed at the contact point with the thickness of the rear shroud 42b.

In the present invention, geometrical tolerances such as coaxiality, squareness, flatness, and parallelism can be determined between the hole portion and end surface portion of the cylindrical spacer 12e and the rotating shaft 2 instead of the conventional rear surface shroud 42b. In addition, the cylindrical spacer 12e has a larger overall length than the rear shroud 12a, so that the contact point and the contact area with the rotary shaft 2 are increased.

  The D-cut surface 12g may have a tolerance that allows the impeller 12 and the rotary shaft 2 to be prevented from rotating as long as the D-cut surface 12g is in surface contact with the rotary shaft 2, and may be cut if it is relatively looser than the hole tolerance. No processing or polishing is required, and it is possible to prevent rotation even with the tolerance of the cast part and the cast surface of the cast part. As described above, the geometrical tolerance, which is the assembly tolerance of the rotating shaft 2 and the impeller 12, is improved by the hole tolerance of the cylindrical spacer 12e.

  When assembly, processing, etc., the tighter dimensional and geometric tolerances of the rotating shaft 2 and the cylindrical spacer 12e reduce the surface vibration of the electric blower, resulting in a low vibration, low noise, high efficiency electric blower configuration. However, dimensional tolerance, geometric tolerance, position size of D-cut 12g surface, D-cut shape, and D-cut tolerance depend on the operating conditions (rotation speed and fan output) and assembly conditions of the electric blower. It is necessary to experimentally obtain an optimum value according to the conditions of the electric blower.

  The motor case 15 has a conical shape that expands at a predetermined angle from the upstream side to the downstream side of the air passage 14, and the air guide 15 a is in contact with the inner wall of the motor case 15. Accordingly, a series of independent air passages formed by the first independent air passage 16 and the second independent air passage 18 communicating with the first independent air passage 16 continuously increase in cross-sectional area from the upstream side to the downstream side of the air passage 14. Yes.

  Further, the impeller 12 inlet tip and the fan case 13 are made of a resin material such as PTFE and are dynamically sealed through an annular ring 19 in a state where the impeller 12 can be driven to rotate.

  FIG. 4 is a rear view of the impeller 12 in which a plurality of D-cut surfaces 12g are formed on the cylindrical spacer 12e. A plurality of D-cut surfaces 12g are formed into a substantially quadrangular shape.

  In FIG. 5, the vacuum cleaner 20 includes a vacuum cleaner main body 25 having a dust collection chamber 22 communicating with the main body intake port 21 and a blower chamber 24 having a main body exhaust port 23, and a main body intake port 21 in the dust collection chamber 22. A dust bag 26 that is airtightly mounted, an electric blower 1 a installed in the blower chamber 24, a soundproof cover 27 made of a flame-retardant resin material covering the electric blower 1 a, and the upper and lower portions of the blower chamber 24. The sound-absorbing material 28 is disposed on the surface. Although not shown, a hose and an extension pipe are sequentially connected to the main body inlet 21, and a nozzle for sucking dust on the floor is attached to the tip of the extension pipe.

  About the electric blower comprised as mentioned above and the vacuum cleaner using the same, the operation | movement and an effect | action are demonstrated below.

  First, the operation of the electric blower 1a will be described. In FIG. 1, a rotating magnetic field is generated by exciting the winding 4, the rotor 3 rotates in synchronization with the rotating magnetic field, and the impeller 12 fixed to the rotating shaft 2 rotates. The impeller 12 is a so-called centrifugal blower, which is obtained by centrifugal force that air energy receives from rotation, and is characterized in that the gas suction direction and the discharge direction are not linear but are bent substantially at right angles. .

The impeller 12 is a resin or the like that sucks air from the central portion and blows air to the outer peripheral portion with a front shroud 12b having an umbrella-shaped disk shape having an air inlet at the center and a rear shroud 12a having a flat disk shape. Since the blade 12c is sandwiched and supported by an inducer 12d formed by a press of aluminum sheet metal and iron metal sheet metal, the impeller 12 rotates together with the rotation of the rotary shaft 2. Due to the generated centrifugal force, the air in the impeller 12 extends along the shape of an umbrella-shaped disc-shaped front shroud 12b from the intake port disposed in the center of the impeller 12, and the inducer 12d is also disposed in the impeller 12. It is scraped out by the blade 12c and pushed toward the outer periphery in the impeller 12 and backward, and the inside of the impeller 12 becomes negative pressure.

  Inside the impeller 12 having a negative pressure, air flows into the impeller 12 from the central intake port, and an airflow flowing into the impeller 12 is generated. The airflow flows in the axial direction from the air inlet at the center of the impeller 12, flows along the front shroud 12 b, the rear shroud 12 a, the inducer 12 d, and the blade 12 c, and then flows out from the outer peripheral direction of the impeller 12.

  In this embodiment, as shown in FIGS. 2 and 3, the impeller 12 fixed to the rotating shaft 2 of the electric blower 1a rotates at a high speed, but the cylindrical spacer 12e of the impeller 12 and the rotating shaft 2 are D-cut. By making surface contact with the surface 12g and fixing the rotation stop, the coaxiality and perpendicularity, which are the mounting accuracy of the impeller and the rotating shaft, are improved with a simple structure and configuration, and surface runout due to high-speed rotation of the impeller is reduced. It is possible to reduce the vibration and noise of the electric blower and improve the product reliability. Further, by reducing the core blur of the impeller 12, the clearance between the outer periphery of the impeller 12 and the air guide can be reduced, and the leakage of the recirculation between the impeller 12 and the air guide can be reduced and the fan efficiency can be improved.

  Further, by suppressing the impeller 12 surface runout, the impeller 12 can be further rotated at a rotational speed of 30,000 to 45,000 r / min, even at a high speed of 45,000 to 120,000 r / min. It is possible to reduce damage to contact with other parts and collision, and to improve fan output by high-speed operation. Further, the cylindrical spacer 12e is disposed through the rear shroud 12a, and the impeller 12 and the rotary shaft 2 can be fixed by surface contact by disposing at least one surface facing the rotary shaft 2. It is possible to prevent the impeller 12 and the rotating shaft 2 from rotating together.

  Further, the arrangement of the opposing surfaces makes it possible to transmit the torque generated by the motor unit and the rotating shaft 2 to the impeller 12 without waste, and can cope with various operating conditions. For example, the electric blower 1a operated at high speed is subjected to operation control such as rapid acceleration and rapid deceleration. By making surface contact with the opposing surfaces, the impeller 12 can be instantaneously synchronized with the movement of the rotating shaft 2 for rapid acceleration or deceleration by surface contact. Therefore, the electric blower 1a is capable of various operating conditions.

  Moreover, as shown in FIG. 4, the cylindrical spacer 12e and the rotating shaft 2 are arranged in a plurality of opposite surfaces so as to be a plurality of so-called D-cut surfaces 12g, and the cylindrical spacer 12e and the rotating shaft Compared with the case where the contact area with 2 is opposed to one surface, the load (stress) applied to the D-cut surface 12g is distributed by increasing the number of surfaces that receive a load (stress) due to high-speed rotation because there are multiple surfaces. And the stability of the mounting property and reliability of the impeller 12 can be increased. Thus, an increase in sliding loss due to the joint rotation of the impeller 12 and the rotating shaft 2 can be prevented.

  The air inlet sucks gas into the central portion of the front shroud 12b, and the resin inducer 12d passes between the blades 12c made of sheet metal and discharges from the outer periphery of the impeller 12 without greatly disturbing the air flow. At this time, the impeller operates at a high speed of 30,000 to 45,000 r / min, but the cylindrical spacer inside the inducer 12d fixed to the high-speed rotating shaft 2 constitutes the base of the inducer 12d. The hub 12f has a cylindrical spacer 12e for fixing the rotary shaft 2, and the cylindrical spacer 12e is arranged to penetrate the rear shroud 12a so that the impeller 12 and the rotary shaft 2 can be attached with the same degree of coaxiality. In addition, the perpendicularity is improved by a simple structure and configuration.

  As a result, the impeller 12 and the rotating shaft 2 of the motor can contact not only the contact due to the plate thickness of the rear shroud 12a but also the inner cylindrical portion of the cylindrical spacer 12e, and the contact area between the rotating shaft 2 and the impeller 12 is increased. can do. Therefore, the impeller 12 is operated at a high speed of 30000 to 45000 r / min, and a surface that vibrates back and forth around the rotary shaft 2 in the direction of the rotary shaft 2 in the outer peripheral portion of the impeller 12 with the high speed rotation. Factors that cause the phenomenon of vibration and increase fan noise can be suppressed by improving the accuracy of coaxiality between the impeller and the rotating shaft because the impeller 12 contacts the cylindrical portion of the cylindrical spacer 12e.

  Further, conventionally, the rear surface shroud 12a in the end surface portion of the cylindrical spacer 12e and the rotary shaft 2 is thin and is difficult to clamp and fix because of cost reduction and production cycle improvement. The rear shroud 12a, which is a difficult part, is often produced by punching with a sheet metal press product. Since the material shape remains as it is, the size of the rear shroud 12a is larger than that of the cylindrical spacer 12e. There were some cases in which the surface shape of the target flatness and the parallelism was out of order.

  By contacting the rotary shaft 2 with the rear shroud 12a, the rotary shaft 2 and the impeller 12 can improve the hole accuracy of the rear shroud 12a, but the rear shroud 12a having a large size is used when the impeller 12 is assembled and attached. In some cases, the verticality may be reduced.

  Compared with the rear surface shroud 12a, the end surface portion of the cylindrical spacer 12e, which is a small size, has good flatness and parallelism, and the geometric tolerance is good, and the cylindrical inner diameter portion of the cylindrical spacer 12e has good perpendicularity to the end surface portion. It is. Therefore, when the end face portion of the cylindrical spacer 12e, the collar 30 and the spacer 32 are in contact with the bearing 9, the accuracy of the coaxiality of the impeller 12 is improved, and the accuracy of the verticality of attachment between the impeller 12 and the rotary shaft 2 is also improved. It becomes possible.

  In the normal electric blower 1a, the impeller 12 having improved coaxiality and verticality is designed with a small clearance between the impeller 12 portion, the fan case 13, and the air guide 15a for high efficiency. It is also possible to suppress the longitudinal vibration of the part, and it is possible to reduce the possibility of damage due to contact of the outer peripheral part of the impeller 12 with the fan case 13 and the air guide 15a.

  Further, even when the fan is further rotated at a high speed, for example, at a high speed of 45,000 to 120,000 r / min, in order to obtain a further increase in output, the coaxiality, cylindricity, and verticality of the impeller 12 are increased. Further, since the geometric tolerance of the flatness and the parallelism is improved, it is possible to reduce the surface runout of the impeller 12 and to reduce the problem that the reliability of the fan portion is lowered.

  Further, by improving the accuracy of the coaxiality and perpendicularity between the impeller 12 and the rotating shaft 2, the clearance between the outer periphery of the impeller 12 and the air guide 15a can be reduced, and leakage of the recirculation between the impeller 12 and the air guide 15a can be reduced. Is possible. Further, the improvement in accuracy over the prior art means that leakage called recirculation loss has conventionally occurred between the outer periphery of the impeller 12 and the air guide 15a, which causes a decrease in fan performance. Although it was difficult to close the clearance due to impeller 12 contact or damage due to collision, impeller surface run-out can be reduced by improving the accuracy of the coaxiality and perpendicularity between the impeller 12 and the rotary shaft 2.

Since the cylindrical spacer 12e and the rotary shaft 2 are configured by surface contact with the D-cut surface 12g, even when the clearance between the impeller 12 and the air guide 15a is reduced, the common rotation can be prevented. It becomes possible to provide a highly efficient electric blower 1a capable of preventing phase shift.

  Among them, a plate-like spacer 32 is arranged on the rear shroud 12 a located on the bottom surface of the impeller 12, and a cylindrical collar 30 is arranged on the front frame 10 a side which is the rear portion of the plate-like spacer 32. The rotary shaft 2 has a cylindrical collar 30, a plate-like spacer 32, and an impeller 12 in order from the bearing 9 on the frame front 10a side, and is fastened to the rotary shaft 2 with a nut 33. By placing spacers 32 on the bottom surface portion of the rear shroud 12a located on the bottom surface portion of the impeller 12 which provides flatness to the rotating shaft 2 and assists rigidity, the weight is reduced for relatively low density. The impeller 12 that is light and is assembled using a thin plate causes surface runout due to its centrifugal force and pressure when rotating at high speed, but by providing a spacer, rigidity of the rear shroud 12a is assisted. It is.

  A collar 30 made of sintered, brass, or the like is formed on the bottom surface of the spacer 32, and the impeller 12 is rotated around the rotating shaft 2 by the nut 33 via the spacer 32 and the collar 30. Fixed to prevent.

  The spacer 32, the collar 30, and the cylindrical spacer 12e are made of metal such as aluminum, iron, a sintered alloy, or brass. Also, other resin materials and metal materials are possible, and they may be composed of resin materials and metal materials with good wear resistance and slidability, and materials that can withstand the rigidity of the tightening pressure when fastened to the nut 33. The effect according to the present invention does not change.

  Since the spacer 32, the collar 30, and the cylindrical spacer 12e are important parts that determine the assembly accuracy of the impeller 12 and the electric blower, as in the past, sheet metal pressing, cutting, polishing, molding, casting, casting, rolling Any effect can be obtained as long as it is manufactured by various processing methods and has a precise processing accuracy equivalent to that of the prior art.

  The hole tolerance between the rotating shaft 2 and the cylindrical spacer 12e is as tight as possible in terms of assembly and processing. Conventionally, since the rotation shaft 37 and the rear surface shroud 42b have determined the geometrical tolerance in assembly such as the coaxiality, perpendicularity, flatness, parallelism, etc. of the impeller 12 due to the hole tolerance, the rear surface shroud 42b and the rotation shaft 2 are The geometric tolerance was suppressed at the contact point with the thickness of the rear shroud 42b.

  In the present invention, geometrical tolerances such as coaxiality, squareness, flatness, and parallelism can be determined between the hole portion and end surface portion of the cylindrical spacer 12e and the rotating shaft 2 instead of the conventional rear surface shroud 42b. In addition, the cylindrical spacer 12e has a larger overall length than the rear shroud 12a, so that the contact point and the contact area with the rotating shaft 2 are increased, and the axial center accuracy is improved.

  When assembly, processing, etc., the tighter dimensional and geometric tolerances of the rotating shaft 2 and the cylindrical spacer 12e reduce the surface vibration of the electric blower, resulting in a low vibration, low noise, high efficiency electric blower configuration. However, the dimensional tolerance, geometric tolerance, position size of the D-cut surface 12g, D-cut shape, and D-cut tolerance depend on the operating conditions (rotation speed and fan output) and assembly conditions of the electric blower. It is necessary to experimentally obtain an optimum value according to the conditions of the electric blower.

  As described above, there is a minute clearance between the rotary shaft 2 and the cylindrical spacer 12e. When the sheet metal blade 12c and the front and rear shrouds 12a and 12b are caulked, the cylindrical spacer 12e is disposed at the center of the inducer 12d and is sandwiched between the inducer 12d and the rear shroud 12a so as to be finely movable. . The operation of the above configuration is as follows.

The impeller 12 into which the spacer 32, the collar 30 and the cylindrical spacer 12e inserted into the rotating shaft 2 are inserted together with the rotating shaft 2 at the D-cut surface 12g of the cylindrical spacer 12e is sequentially inserted and fastened by the nut 33. When the impeller 12 is inserted, the position with respect to the rotary shaft 2 is determined by the D-cut surface 12g of the cylindrical spacer 12e. The airflow flowing out from the impeller 12 flows into the plurality of first independent air passages 16 and then flows along the outer peripheral surface of the frame front 10a through the plurality of second independent air passages 18 communicating with the plurality of first independent air passages 16 to the outside of the electric blower 1a. Spill into.

  At that time, since the cross-sectional area of the series of independent air paths formed by the first independent air path 16 and the second independent air path 18 increases from the upstream to the downstream, the dynamic pressure is reduced while the airflow is decelerated. Is converted to pressure. The blowing performance of the electric blower 1a is expressed as a ratio between the electric power input to drive the electric blower 1a and the work performed by the electric blower 1a (the product of the degree of vacuum and the flow rate generated by the rotation of the impeller 12). . For this reason, increasing the degree of vacuum (static pressure) generated by the electric blower 1a at the actual flow rate is very important for improving the blowing performance of the electric blower 1a.

  Further, the heat generated by the brushless motor 11 may be due to copper loss, iron loss, or mechanical loss. The copper loss is Joule heat generated by the current flowing through the winding 4 and increases in proportion to the square of the current. Iron loss is divided into hysteresis loss and eddy current loss. Hysteresis loss is caused by the physical properties of the electrical steel sheet forming the magnetic path of the motor, and is caused by the change in the magnetic flux density due to the change of the magnetic field due to the rotation. The eddy current loss is caused by an electric resistance at the time when an eddy current flows around the magnetic flux line due to the fluctuation of the magnetic flux passing through the core 5a. The mechanical loss is caused by the friction of the bearing 9 and the air agitation resistance between the rotor 3 and the stator 6.

  In particular, the iron loss increases depending on the operating frequency both for the hysteresis loss and the eddy current loss. Therefore, when the brushless motor 11 is used at high speed, the heat generated by the iron loss is increased, and this is how efficient it is. It is important to make heat dissipation well. In the vacuum cleaner 20, since the electric blower 1a is mostly used in the high-speed rotation region, cooling the core 5a is very important in order to obtain a small size and high blowing performance.

  The heat generated in the core 5a is conducted to a plurality of second guide vanes 8a fitted and fixed in a linear groove 7a provided on the outer peripheral portion of the core 5a, and an independent air path from the surface of each guide vane. Heat is transferred to the airflow from the impeller 12 flowing through the brushless motor 11 and goes out of the brushless motor 11.

  Since the core 5a and the second guide vane 8a are bonded with an adhesive having high thermal conductivity, it is possible to prevent a minute gap from being formed in the fitting portion, and the thermal contact resistance of the fitting portion is reduced. Thus, the thermal conductivity from the core 5a to the second guide vane 8a can be improved, and the heat generated in the core 5a can be easily conducted to the second guide vane 8a, and the second guide vane 8a. Is continuously forcibly cooled by the airflow from the impeller 12, a temperature difference is generated between the second guide vane 8 a and the core 5 a, heat conduction inside the core 5 a is promoted, and the core 5 a is efficiently Heat can be released to the outside of the brushless motor 11.

  Further, by using aluminum having high thermal conductivity, the heat conducted from the core 5a can be easily transmitted to the entire second guide vane 8a, and the second guide vane 8a can be handled as a radiating fin. It becomes possible to cool the motor 11 efficiently.

  Further, the heat generated in the winding 4 is conducted through the mold part 17 formed of a heat conductive resin, is transmitted to the plurality of second guide blades 8a held at both ends, and is conducted from the core 5a. Through the same process as heat, it is transmitted to the airflow from the impeller 12 and goes out of the brushless motor 11. Since a heat conductive resin is used for the mold part 17, the heat conductivity is remarkably higher than that of air, and the heat generated in the winding 4 can be efficiently radiated.

  In addition, it is preferable to select a material having high thermal conductivity for the second guide vane 8a. In addition to aluminum, a metal material such as copper or silver, a hard metal or carbon powder or fiber having thermal conductivity is used. A heat conductive resin whose heat conductivity is improved by containing a filler such as filler may be used. The heat of the core 5a is transmitted to the second guide blade 8a to increase the heat radiation area, and the brushless. It is possible to enhance the cooling effect of the motor 11.

  As the heat conductive resin, polyphenylene sunfide resin (PPS), nylon and liquid crystal polymer (LCP) are known. Metal powder, graphite, carbon black, etc. are used as the conductive filler, and sintered ceramics, such as aluminum nitride, boron nitride, and alumina, are used as the insulating filler. It is necessary to use different fillers for each part.

  However, for the plurality of second guide vanes 8a functioning as heat radiating fins, it is possible to increase thermal conductivity by using a resin blended with a conductive filler compared to a resin blended with an insulating filler. It is desirable to use a resin containing a conductive filler. When the blending ratio of the filler is increased, the viscosity at the time of melting is increased and the moldability is lowered, so care must be taken.

  Further, the thickness and the number of blades of the second guide vanes 8a are such that the cross-sectional area required as a diffuser, the change rate of the cross-sectional area, and the stator with respect to the plurality of second independent air passages 18 formed in the air passage 14 It is necessary to determine both from the heat radiation capacity necessary for the cooling of 6, and it is necessary to obtain the optimum value experimentally. In this embodiment, the configuration of the brushless motor is described. However, the present invention is not limited to this, and the present invention is applicable even when a commutator motor or the like used in a conventional electric blower is used. Does not change the effect.

  Further, the electric blower 1a is required to further improve the output in order to improve the suction performance of the vacuum cleaner 20, and as described above, the rotational speed of the conventional electric blower 1a is 30,000 to 45,000 r / min. However, in the future, higher speed operation will be performed at 45,000 to 120,000 r / min. At the same time as the impeller 12 rotates at high speed, centrifugal force and pressure inside the impeller increase in the impeller 12, so that the surface vibration of the impeller 12 increases. However, since the impeller 12 fixed by the cylindrical spacer 12e of the present invention has a large contact point and contact area with the rotating shaft, even if the speed is increased, vibration and noise are reduced in order to reduce surface run-out compared to the prior art. It becomes possible to cope with efficiency.

  Next, operation | movement of the vacuum cleaner 20 is demonstrated using FIG. In FIG. 5, when the impeller 12 of the electric blower 1 a rotates, the dust collection chamber 22 is in a negative pressure state, and an air flow including dust sucked from a nozzle (not shown) passes through the main body intake port to collect the dust collection chamber. 22 flows in. The clean airflow obtained by filtering and separating the dust with the dust bag 26 flows into the impeller 12 of the electric blower 1a, passes through the first independent air passage 16 and the second independent air passage 18 communicating with the first independent air passage 16, and then the soundproof cover. 27 flows out from the exhaust port 27 and is discharged to the outside of the cleaner body 25.

  Since the vacuum cleaner 20 is equipped with an electric blower 1a that is small and has high blowing performance, it has a strong suction force, good dust removal, and the electric fan 1a has a small body size and light weight. Convenient and convenient to use. In addition, the space in which the sound absorbing material 28 can be disposed in the cleaner body 25 is expanded, and the installation area of the sound absorbing material 28 provided in the cleaner body 25 is increased, so that the sound absorbing area can be expanded and the operation sound can be reduced. It is also possible to use the vacuum cleaner 20.

As described above, in the present embodiment, the cylindrical spacer 12e of the impeller 12 is disposed through the rear shroud 12a, thereby suppressing the shaft center blur of the impeller 12, thereby reducing the vibration and noise of the electric blower. Reliability can be improved. Further, by reducing the axial blur, the clearance between the outer periphery of the impeller 12 and the air guide 15a can be reduced, and a highly efficient electric blower with reduced leakage of the impeller 12 and the air guide 15a can be provided.

(Embodiment 2)
FIGS. 6-7 shows the figure of the electric fan impeller part in the 2nd Embodiment of this invention. FIG. 6 is a rear view of the impeller portion provided with the key joint 35a according to the second embodiment of the present invention. FIG. 7 is a rear view of an impeller portion provided with a plurality of key joints 35a according to the second embodiment of the present invention.

  In addition, about the same part as Embodiment 1, the same code | symbol and the same name are attached | subjected, and the description is abbreviate | omitted. FIG. 6 is a rear view of the impeller 12 portion, and shows a state in which the cylindrical spacer 12e is disposed through the rear shroud 12a and is arranged on the rotating shaft and the cylindrical spacer by the key joint 35a. In addition, the configuration of the impeller 12 is the same as that of the first embodiment.

  The cylindrical spacer 12e has an outer diameter portion formed in a cylindrical shape, and is fixed to the inducer 12d as described above. At least one key joint 35a is arranged and configured in a portion combined with a part of the rotary shaft 2 on the rear surface shroud 12a side of the inner diameter portion of the cylindrical spacer 12e. The rotary shaft 2 and the cylindrical spacer 12e are arranged and configured in surface contact with each other by a key joint 35a. Thereafter, as described above, the rotary shaft 2 is fastened by the nut 33 from the front shroud 12b side.

  The key joint 35a is made of metal such as aluminum, iron, structural alloy steel, carbon steel for mechanical structure, sintered alloy, or brass. Any material that is harder than at least the rotating shaft 2 and the cylindrical spacer 12e may be used. Any material can be used as long as it can withstand the shear stress applied when the impeller 12 rotates, and the effect of the present invention is not changed, and the present invention is not limited to this material.

  On the other hand, the key groove 35b portion of the cylindrical spacer 12e and the rotary shaft 2 is also reliable in the condition that the bottom of the key groove 35b does not cause shear failure or compression failure with respect to the transmission torque of the impeller 12 and the rotary shaft 2 like the key joint 35a. It is also required from sex. In addition, the cylindrical spacer 12e, the key groove 35b portion provided on the rotating shaft, and the key portion are important parts that determine the assembly accuracy of the impeller 12 and the electric blower as in the conventional case, and therefore, cutting, polishing, molding As long as it is manufactured by casting, casting, various processing methods and has the same precise processing accuracy as before, the effect of the present invention does not change.

  The fitting tolerance between the key shaft 35b of the rotary shaft 2 and the cylindrical spacer 12e and the key portion may be any fitting tolerance as much as possible in terms of assembly and processing, and may be either a clearance fit or a tight fit. . Further, the shape of the key joint 35a may be a parallel key, a half-moon key, or a gradient key. In addition, depending on the state of use, a combination of a sinking key joint with a shape that sinks a keyway common to the shaft and boss, or two keys with a slope on one side, and driving in the tangential direction of the shaft. There are no restrictions on the type or shape of key joints or key joints that do not create a key groove on the shaft and transmit torque only by the frictional force generated by driving.

  The detailed dimensional tolerance, geometrical tolerance, position dimensions, and shape of the key part and key groove 35b part depend on the operating conditions (rotation speed and fan output) and assembly conditions of the electric blower. Accordingly, it is necessary to experimentally obtain an optimum value.

  About the electric blower comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  In addition, about the operation | movement of the same part as Embodiment 1, and an effect | action, the same code | symbol and the same name are attached | subjected, and the description is abbreviate | omitted.

  First, in the present embodiment, the impeller 12 fixed to the rotating shaft 2 of the electric blower 1a is rotated at a high speed and operated. There is a concern that the impeller 12 may be rotated even if the impeller 12 cannot cope with the rotational force of the rotating shaft 2 due to the rotational force (torque) accompanying the high-speed rotation of the rotating shaft 2. However, in the present embodiment, it is a structural element for mechanically coupling the cylindrical spacer 12e of the impeller 12 with the key groove 35b formed on the rotary shaft 2 and the key joint 35a. Since the rotational force is accurately transmitted to the cylindrical spacer 12e of the impeller 12 using the key groove 35b and the key joint 35a as a medium, it is possible to prevent the impeller 12 and the rotating shaft 2 from rotating together. It can also cope with operating conditions.

  For example, the electric blower 1a operated at a high speed of 30,000 to 45,000 r / min is subjected to operation control such as rapid acceleration and rapid deceleration. If the impeller 12 does not have a medium that accurately transmits the rotational force of the rotating shaft 2 due to acceleration / deceleration operations such as sudden acceleration or sudden deceleration, the impeller 12 and the rotating shaft 2 rotate together and cannot respond instantaneously. . However, the key joint allows the impeller 12 to instantaneously synchronize the movement of the rotating shaft 2 for rapid acceleration or deceleration using the key joint as a medium to transmit the rotational force to the impeller 12. Therefore, the cylindrical spacer 12e of the impeller 12 and the rotary shaft 2 can be prevented from rotating, and an increase in sliding loss due to the joint rotation of the cylindrical spacer 12e of the impeller 12 and the rotary shaft 2 can be prevented. It is possible to deal with conditions.

  In addition, according to the present embodiment, it is possible to prevent co-rotation even at a high speed of 45,000 to 120,000 r / min with further improved rotational speed, and fan output can be improved by high speed rotation. .

  In addition, by accurately transmitting the rotational force of the rotating shaft to the impeller using the key joint as a medium, the rotation of the impeller is stably rotated in synchronization with the rotating shaft, so that an electric blower with reduced vibration and noise is obtained. Product reliability can be improved.

  Further, as shown in FIG. 7, the cylindrical spacer 12e and the rotary shaft 2 are constituted by a plurality of key joints and a key groove 35b portion, whereby the cylindrical spacer 12e and the rotary shaft 2 of the impeller 12 are connected. A plurality of parts where the rotational force can be accurately transmitted to the cylindrical spacer 12e of the impeller 12 using the key joint, which is a structural element for mechanical coupling, as a medium are increased, and the area that receives a load due to high-speed rotation increases. Thus, shear failure and compression failure due to shear stress applied to the groove and the key joint 35a during rotation can be prevented, and the mounting strength and stability of the impeller 12 can be increased. Therefore, it is possible to prevent an increase in sliding loss due to the co-rotation of the impeller 12 and the rotating shaft 2, and it is possible to cope with various operating conditions.

  As described above, the electric blower according to the present invention can reduce the vibration and noise of the electric blower by reducing the impeller surface fluctuation by improving the impeller mounting accuracy, and reducing the clearance between the impeller and the air guide. The fan efficiency can be improved with the impeller, the D-cut surface 12g of the impeller and the rotating shaft, and the rotation stop by the key joint 35a can cope with severe operation such as acceleration / deceleration operation, and the fan can be operated at high speed. A highly efficient electric blower with high suction performance and high reliability can be obtained, and the present invention can be applied not only to a floor moving type AC vacuum cleaner but also to a handy type, a vertical type, or a DC rechargeable vacuum cleaner.

DESCRIPTION OF SYMBOLS 1a Electric blower 2 Rotating shaft 3 Rotor 4 Winding 5a Core 6 Stator 7a Groove (concave part)
8a Second guide vane 9 Bearing 9a Ball portion 9b Outer ring 9c Inner ring 9d Seal plate 10a Front of frame 10b After frame 11 Brushless motor 12 Impeller 12a Rear shroud 12b Front shroud 12c Blade 12d Inducer 12e Cylindrical spacer 12f D Hub 12g 13 Fan case 20 Vacuum cleaner 30 Color (washer)
32 Spacer 33 Nut 35a Key fitting 35b Keyway

Claims (5)

A motor in which a rotor having a rotating shaft and a stator are arranged to face each other;
Holding a bearing that supports at least one end of the rotating shaft, and a frame that covers the bearing and the stator;
A front shroud fixed to the end of the rotating shaft and having a suction port in the center;
A rear shroud facing the front shroud;
An impeller configured by sandwiching a plurality of blades and an inducer joined to the suction port side of the blades between the pair of shrouds,
In the impeller, inside the hub constituting the base of the inducer,
A cylindrical spacer for fixing the rotating shaft;
The cylindrical spacer is disposed through the rear shroud,
The cylindrical blower and the rotating shaft are electric blowers arranged to have at least one surface facing each other. The electric blower according to claim 1, wherein the cylindrical spacer and the rotation shaft are arranged to penetrate through a plurality of opposing surfaces. A motor in which a rotor having a rotating shaft and a stator are arranged to face each other;
Holding a bearing that supports at least one end of the rotating shaft, and a frame that covers the bearing and the stator;
A front shroud fixed to the end of the rotating shaft and having a suction port in the center;
A rear shroud facing the front shroud;
An impeller configured by sandwiching a plurality of blades and an inducer joined to the suction port side of the blades between the pair of shrouds,
In the impeller, inside the hub constituting the base of the inducer,
A cylindrical spacer for fixing the rotating shaft;
The cylindrical spacer is disposed through the rear shroud,
The cylindrical blower and the rotary shaft are electric blowers arranged with at least one key joint that fits each other. The electric blower according to claim 3, wherein the cylindrical spacer and the rotation shaft are configured by a plurality of key joints. The vacuum cleaner carrying the electric blower of Claims 1-4.