JP4320803B2 - Electric blower - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric blower having a centrifugal fan directly connected to a rotating shaft of a commutator electric motor, a diffuser disposed coaxially with the centrifugal fan, and a fan casing covering the centrifugal fan and the diffuser.
[0002]
[Prior art]
A conventional electric blower will be described with reference to FIG.
[0003]
The electric blower mainly includes a commutator motor, a centrifugal fan 12 directly connected to a rotating shaft of the commutator motor, a diffuser 13 coaxially arranged with the centrifugal fan on the outer peripheral side of the centrifugal fan, and fixed to the commutator motor, and a diffuser. And a fan casing 15 that covers the centrifugal fan 12 and the diffuser 13. The fan casing 15 is assembled by being press-fitted into the housing of the electric motor up to a position where the fan casing 15 contacts the upper surface of the diffuser 13 and sandwiches the diffuser.
[0004]
When the commutator motor starts operation, the air flows into the centrifugal fan from the air intake port 16 by the rotation of the centrifugal fan directly connected to the rotating shaft of the commutator motor, and is given dynamic pressure by the centrifugal force and flows into the diffuser. Then, the flow velocity is reduced and the pressure is restored to static pressure. The return guide guides the commutator motor through the commutator motor and releases it to the outside.
[0005]
Generally, the fan casing is formed into a complicated shape by pressing, and the diffuser is made of a molded product having a large number of blade blades having a complicated shape. For this reason, the surface of the fan casing that contacts the upper surface of the diffuser has unevenness due to unevenness in press work and unevenness due to distortion, and the upper surface of the diffuser also has unevenness due to sink marks and deformation. For this reason, when the electric blower is assembled, there is a gap in the surface where the fan casing and the diffuser upper surface come into contact, and a part of the air flow flowing into the diffuser from the centrifugal fan flows in the circumferential direction through the gap, and the leakage between the blades The flow reduces the performance of the electric blower accordingly.
[0006]
Therefore, for example, Japanese Utility Model Laid-Open No. 3-13499 discloses the following technique as means for closing the gap and preventing air from flowing in the circumferential direction.
[0007]
1) An elastic body is provided on the upper surface of the diffuser so that the surface in contact with the fan casing is in close contact.
[0008]
2) An elastic coating material is attached to the surface of the fan casing that contacts the upper surface of the diffuser, and the fan casing and the upper surface of the diffuser are adhered to each other.
[0009]
Japanese Patent Laid-Open No. 6-193595 discloses the following technique.
[0010]
1) A groove having the same shape as the upper surface of the diffuser is provided on the surface of the fan casing that contacts the upper surface of the diffuser, and the upper surface of the diffuser and the groove of the fan casing are fitted to increase the fluid resistance of the gap between the fan casing and the upper surface of the diffuser. Air makes the gap difficult to flow in the circumferential direction.
[0011]
2) Between the upper surface of the diffuser and the fan casing, a sheet (in the embodiment, a rubber having a thickness of 0.1 to 0.3 mm is interposed to seal the gap to prevent air from flowing in the circumferential direction. To do.
[0012]
[Problems to be solved by the invention]
However, in the technique disclosed in the above-mentioned Japanese Utility Model Publication No. 3-13499, the upper surface of the diffuser is composed of dozens of wings, and it is necessary to accurately provide an elastic body for each of the wings. There were drawbacks such as poor workability and workability.
[0013]
In addition, in the technology of attaching an elastic coating material to the surface of the fan casing in contact with the upper surface of the diffuser, masking must be performed to prevent the coating material from adhering to unnecessary portions. Since it has a complicated shape, there is a drawback that workability is very poor.
[0014]
Further, the technique disclosed in Japanese Patent Application Laid-Open No. 6-193595 has a drawback that it is difficult to accurately align the groove of the fan casing and the upper surface of the diffuser, and the assembly and workability are poor. It was.
[0015]
Furthermore, in the technology of interposing a sheet between the upper surface of the diffuser and the fan casing, the intervening sheet must seal the unevenness caused by variations in the press processing of the fan casing and the gap caused by the sinker or deformation of the diffuser. The sheet must be thickened, and in this case, the amount of biting into the sheet on the upper surface of the diffuser becomes large at a small gap, and the area of the flow path 19 of the diffuser is reduced as shown in FIG. There are disadvantages. Further, when the sheet is made thin in order to reduce the amount of biting, the sheet flutters due to the air flow flowing through the flow path of the diffuser, which may generate noise and increase air resistance, causing a decrease in performance of the electric blower.
[0016]
Further, when the center of the diffuser and the center of the seat are shifted during assembly, there is a risk that the inner peripheral side of the seat and the outer peripheral side of the centrifugal fan come into contact with each other and cause damage to the electric blower.
[0017]
Accordingly, an object of the present invention is to solve the above-described problems and to effectively eliminate a gap at the surface where the fan casing and the upper surface of the diffuser are in contact with each other to provide an electric blower with high efficiency.
[0018]
[Means for Solving the Problems]
A feature of the present invention for solving the above-described problems is that a centrifugal fan directly connected to a rotating shaft of a commutator motor, and an outer peripheral side of the centrifugal fan arranged coaxially with the centrifugal fan and fixed to the commutator motor An electric blower that includes a centrifugal fan and a fan casing that covers the diffuser, and press-fits the fan casing into a housing of a commutator motor to sandwich the diffuser. An annular part is formed between the upper part of the diffuser blade and the upper part of the blade, and the lower part of the diffuser and the shroud plate of the diffuser are integrally formed on the lower part of the blade. formed, joined and integrated against the upper end surface of the blade lower and lower end surface of the blade upper Configuration and was there to be had was.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail with reference to the drawings.
The present invention includes a centrifugal fan directly connected to a rotating shaft of a commutator motor, a diffuser disposed coaxially with the centrifugal fan on an outer peripheral side of the centrifugal fan and fixed to the commutator motor, the centrifugal fan, and the diffuser. An electric blower that press-fits the fan casing into a housing of a commutator motor and sandwiches the diffuser, and forms an annular portion between the fan casing and the upper surface of the diffuser. The ring portion is configured to be integrally joined to the upper surface of the diffuser. According to the present invention, the annular portion is formed between the fan casing and the upper surface of the diffuser, and the annular portion is joined to and integrated with the upper surface of the diffuser. In addition, the diffuser side can be sealed as a single unit, and a part of the air that has flowed into the diffuser from the centrifugal fan is prevented from flowing in the circumferential direction through the gap. A blower can be realized. The ring part has a simple shape and can be assembled in advance by easily aligning the axis of the ring and the axis of the diffuser. The inner periphery of the ring and the outer periphery of the centrifugal fan are in contact. The risk of causing damage to the electric blower can be avoided.
The present invention also provides a centrifugal fan directly connected to a rotating shaft of a commutator motor, a diffuser disposed coaxially with the centrifugal fan on the outer peripheral side of the centrifugal fan and fixed to the commutator motor, the centrifugal fan, A fan casing that covers the diffuser, and in the electric blower that press-fits the fan casing into the housing of the commutator motor and sandwiches the diffuser, an annular portion is configured between the fan casing and the diffuser, The diffuser blade is integrally formed in an annular portion, and the diffuser blade is in contact with the lower surface of the diffuser. In the second means of the present invention, the annular portion is formed integrally with the diffuser blade, so that the blade side of a plurality of kinds of diffusers can be combined with the same side diffuser part of the diffuser. It is possible and it can be set as multiple types of electric blower.
The present invention also includes a centrifugal fan directly connected to a rotating shaft of a commutator motor, a diffuser disposed coaxially with the centrifugal fan on an outer peripheral side of the centrifugal fan and fixed to the commutator motor, the centrifugal fan, A fan casing that covers the diffuser, and in the electric blower that press-fits the fan casing into the housing of the commutator motor and sandwiches the diffuser, an annular portion is configured between the fan casing and the diffuser, The upper part of the diffuser blade is integrally formed in the annular part, the lower part of the diffuser blade and the diffuser blade are integrally formed, and the upper part of the blade and the lower part of the blade are joined and integrated. It is characterized by having a configuration. According to the third means of the present invention, the upper and lower halves of the diffuser blade are integrally formed with the annular portion and the diffuser side of the shroud plate, respectively, so that the end faces of the respective blades are abutted and joined. With this configuration, when molding with a synthetic resin or the like in a mold, a three-dimensional structure that cannot be realized can be freely designed by selecting the position of the joint surface. As in the case, it is possible to select the blade tip shape and blade cross-sectional shape, and to provide a through hole, unevenness, and groove in the blade middle part, which can be used for improving aerodynamic performance and reducing fluid noise .
[0020]
FIG. 1 shows the internal structure of the electric blower 1.
[0021]
The electric blower 1 is fixed to a rotating shaft 5 and a rotating shaft 5 which are held by a housing 2, a stator 3 fixed to the housing 2, a bearing 4 a provided in the housing 2 and a bearing 4 b provided in the end bracket 17. The rotor 6, the commutator 7 fixed to the rotating shaft 5, the brush 8 for electrical connection with the commutator 7, the holder 9 for holding it and fixing it to the housing 2, and the screw 18, Centrifugal fan 12 fixed to one end, diffuser 13 that reduces the flow rate of the air flow from the centrifugal fan 12 and recovers pressure, return guide 14 that is formed integrally with the diffuser and guides the air flow into the motor, centrifugal fan 12 and diffuser 13 It is comprised by the fan casing 15 which covers.
[0022]
The commutator 7 has commutator pieces on its circumferential surface, and each commutator piece is connected to a coil in the rotor 6. The brush 8 is pressed against the commutator 7 by the spring 10 and is in sliding contact with the commutator 7. Reference numeral 11 denotes a lead wire electrically connected to the brush 8 for connecting the brush 8 and the external electrode, and is connected to a terminal (not shown) provided on the holder 9.
[0023]
When the electric blower 1 starts rotating, the rotor 6 rotates, and the centrifugal fan 12 fixed coaxially with the rotor 6 also rotates. When the centrifugal fan 12 rotates, air flows from the air intake port 16 of the casing 15, flows into the electric motor through the centrifugal fan 12, the diffuser 13, and the return guide 14, and is discharged from the exhaust port of the electric motor to the outside.
[0024]
At this time, if there is a gap in the contact surface between the fan casing and the upper surface of the diffuser, a part of the air flowing into the diffuser from the centrifugal fan flows in the circumferential direction, and this leakage air flow reduces the efficiency of the electric blower. .
[0025]
Therefore, in the first means of the present invention, as shown in FIG. 2, an annular portion 24 is formed between the fan casing and the upper surface of the diffuser, and the annular portion 24 is joined to and integrated with the upper surface of the diffuser. Accordingly, the gap due to the unevenness of the fan casing is sealed by the flat surface 22 in contact with the fan casing, and the gap due to the sink or deformation of the diffuser is bonded and sealed to the upper surface of the diffuser, thereby minimizing the performance degradation.
[0026]
Further, according to this means, if the annular portion 24 is formed of the same material as the diffuser or a similar synthetic resin, and has a rigid structure, the air flow that flows through the diffuser flow path as in the case of interposing a sheet is used. It does not flutter, and it is possible to prevent performance degradation of the electric blower due to generation of noise and increase in air resistance.
[0027]
Furthermore, as shown in FIG. 3, according to the present invention, it is possible to join in advance so that there is no deviation δ between the axial center of the annular portion and the axial center of the diffuser. By assembling a solid, the radial position is defined, the center of the annular part and the center of the centrifugal fan and fan casing coincide, and the inner peripheral side of the annular ring and the outer peripheral side of the centrifugal fan come into contact with each other, causing damage to the electric blower Risk can be avoided. Next, in the second means of the present invention, as shown in FIG. 4, the annular portion 24 is formed integrally with the diffuser blade 23 and joined to the diffuser blade lower surface 25 and the diffuser blade plate 26. Alternatively, it is possible to combine the blade side of a plurality of types of diffusers with respect to the shroud 26 of the same diffuser, and a plurality of types of electric blowers can be obtained.
[0028]
Further, according to the third means shown in FIG. 5, the upper half 23a and the lower half 23b of the diffuser blade are formed integrally with the annular portion 24 and the diffuser shroud plate 26, respectively. The configuration is such that they are joined together, and the shape of the blade tip 29 on the inlet side of the air flow as shown in FIG. 6 and the shape of the blade cross section 30 as shown in FIG. 7 can be freely selected. Further, as shown in FIGS. 8 and 9, one or a plurality of holes 27 and grooves 28 can be provided in the intermediate portion of the blade, which can be used for improving aerodynamic performance and reducing fluid noise. .
[0032]
【The invention's effect】
According to the present invention , by forming the upper half and the lower half of the diffuser blade integrally with the annular portion and the diffuser side of the shroud plate, respectively, the blade end faces are brought into contact and joined, When molding with a synthetic resin or the like in a mold, a three-dimensional structure that cannot be realized can be freely designed by selecting the position of the joint surface. As in the case, it is possible to select the blade tip shape and blade cross-sectional shape, and to provide a through hole, unevenness, and groove in the blade middle part, which can be used for improving aerodynamic performance and reducing fluid noise .
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an electric blower that is an embodiment of the first means of the present invention.
FIG. 2 is a partial cross-sectional view of an electric blower that is an embodiment of the first means of the present invention.
FIG. 3 is an assembly diagram of a diffuser and an annular portion as an embodiment of the first means of the present invention.
FIG. 4 is a partial cross-sectional view of an electric blower that is an embodiment of the second means of the present invention.
FIG. 5 is a partial cross-sectional view of an electric blower that is an embodiment of the third means of the present invention.
FIG. 6 is a perspective view of a blower portion which is an embodiment of the third means of the present invention.
FIG. 7 is a partial cross-sectional view of an electric blower that is an embodiment of the third means of the present invention.
FIG. 8 is a perspective view of a blower portion which is an embodiment of the third means of the present invention.
FIG. 9 is a perspective view of a blower portion which is an embodiment of the third means of the present invention.
FIG. 10 is a partial cross-sectional view of an electric blower showing a problem of a conventional technique.
FIG. 11 is a cross-sectional view of an electric blower showing a problem of a conventional technique.
FIG. 12 is a front view of the electric blower according to the embodiment of the present invention.
FIG. 13 is a bottom view of the electric blower according to the embodiment of the present invention.
FIG. 14 is a side view of the electric blower according to the embodiment of the present invention.
FIG. 15 is a top view of the electric blower according to the embodiment of the present invention.
FIG. 16 is a view showing a diffuser and a return guide according to an embodiment of the present invention.
FIG. 17 is a bottom view of a diffuser according to an embodiment of the present invention.
FIG. 18 is a top view of a diffuser according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 2 ... Housing, 12 ... Centrifugal fan, 13 ... Diffuser, 14 ... Return guide, 15 ... Fan casing, 24 ... Ring part.

Claims (9)

A centrifugal fan directly connected to the rotating shaft of the commutator motor; a diffuser disposed coaxially with the centrifugal fan on the outer peripheral side of the centrifugal fan and fixed to the commutator motor; a fan casing covering the centrifugal fan and the diffuser; In the electric blower that press-fits the fan casing into the housing of the commutator motor and sandwiches the diffuser,
An annular portion is formed between the fan casing and the diffuser, and an upper portion of the blade of the diffuser is integrally formed on the annular portion on the upper surface of the blade, and a lower portion of the blade of the diffuser and a shroud plate of the diffuser Is formed integrally on the lower surface of the blade, and the lower end surface of the upper portion of the blade and the upper end surface of the lower portion of the blade are abutted and integrated to form an electric blower. In claim 1,
The electric blower characterized in that the shape of the blade tip portion protrudes from the joint portion between the blade upper portion and the blade lower portion toward the blade upper surface and the blade lower surface . In claim 1,
An electric blower characterized in that a groove is formed along a joint portion between the blade upper portion and the blade lower portion . In any one of Claims 1 thru | or 3,
The electric blower according to claim 1 , wherein the upper part of the blade and the lower part of the blade are joined by adhesion or welding. In any one of Claims 1 thru | or 4 ,
The electric blower is characterized in that the material of the annular portion is the same material as the diffuser or a material having substantially the same rigidity. In any one of Claims 1 thru | or 5 ,
The electric blower according to claim 1, wherein a convex portion is provided on a concavo-convex portion to which each of the blade upper portion and the blade lower portion is fitted, or one of them. In any one of Claims 1 thru | or 6 .
The electric blower according to claim 1, wherein a convex portion having a cross-sectional shape with a thin tip is provided at a joint portion between the upper portion of the blade and the lower portion of the blade . In claim 1,
One or more through-holes are formed in the joint part of the said blade upper part and the said blade lower part, The electric blower characterized by the above-mentioned. In any one of Claims 1 thru | or 8.
An electric blower characterized in that a flat seal is provided on a portion of the fan casing facing the diffuser.

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