JP7777503B2 - Electric blower and vacuum cleaner equipped with same - Google Patents

Description

The present invention relates to an electric blower and an electric vacuum cleaner equipped with the same.

Electric vacuum cleaners have a built-in electric blower that generates suction power. For example, Patent Document 1 describes a technology for a built-in electric blower in a vacuum cleaner.

Patent Document 1 discloses a fan comprising an impeller-side housing equipped with first axial diffuser vanes, an anti-impeller-side housing arranged downstream of the first axial diffuser vanes and equipped with second axial diffuser vanes, and a fan casing arranged upstream of the impeller-side housing and covering the impeller. The electric motor that drives the impeller is enclosed by the impeller-side housing and the anti-impeller-side housing.

The impeller is inserted onto the rotating shaft of the motor and secured with screws. The fan casing is inserted into the fitting on the impeller-side housing and glued in place. The motor assembly, now integrated with the fan casing, is then assembled to the tab on the opposite side of the housing and glued in place by pouring adhesive into the housing fitting.

JP 2022-81860 A

A gap is formed between the inner surface of the fan casing and the outer periphery of the impeller, and in order to improve the suction performance of the electric blower, it is preferable to make this gap as small as possible.

In the technology described in Patent Document 1, the fan casing is inserted into the fitting of the housing (impeller-side housing) at the position where the outer periphery of the impeller and the fan casing abut, and adhesive is poured into the fitting to adhere and fix them. As a result, depending on the degree of abutment between the outer periphery of the impeller and the fan casing, or variations in dimensional accuracy, the fan casing and the housing may be attached at an angle, causing the outer periphery of the impeller to come into contact with the inner periphery of the fan casing, and the impeller may become locked.

The object of the present invention is to solve the above problems, stabilize the fixed position of the fan casing and housing, and provide an electric blower and an electric vacuum cleaner equipped with the same that suppress impeller rotation failure.

In order to achieve the above object, the present invention provides an electric blower including an electric motor section having a stator and a rotor within a motor housing, an impeller rotationally driven by the electric motor section, a housing covering the outer periphery of the electric motor section and having diffuser blades, and a fan casing connected to the housing and covering the impeller, wherein the outer periphery of the housing is provided with a first protrusion protruding radially outward, and a second protrusion protruding radially outward and positioned at a position offset from a circumferential extension line and an axial extension line of the first protrusion, and the fan casing is provided with a first protrusion protruding radially outward from the outer periphery of the housing. and a circumferential fixing portion that restricts circumferential rotation of the fan casing, wherein the first protrusion is inserted from the side of the notch that connects to the housing, and then the fan casing is rotated circumferentially to move the first protrusion to a position that extends circumferentially of the notch, thereby connecting the fan casing and the housing, and the second protrusion is brought into contact with the circumferential fixing portion to restrict circumferential rotation of the fan casing .

This invention provides an electric blower and an electric vacuum cleaner equipped with the same that stabilize the fixed position of the fan casing and housing and prevent impeller rotation problems.

1 is a perspective view showing a state in which an electric vacuum cleaner 100 according to an embodiment of the present invention is stored in a charging stand. 1 is an exploded view of a vacuum cleaner 100 according to an embodiment of the present invention. FIG. 3 is a view taken in the direction of the arrow III in FIG. 2 . 1 is a perspective view of the appearance of an electric vacuum cleaner 100 according to an embodiment of the present invention. 1 is a cross-sectional view of an electric blower 200 according to an embodiment of the present invention, taken along the rotation axis. FIG. 2 is a side view showing a partial cross section of the right half of an impeller-side housing 212 according to an embodiment of the present invention. FIG. 2 is a perspective view showing a part of a cross section of a housing 213 on the side opposite to the impeller according to an embodiment of the present invention. 2 is a cross-sectional view of a fan casing 230 according to an embodiment of the present invention, taken along the axial direction. 1 is an exploded perspective view of an electric blower 200 according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of an assembly formed by assembling an impeller-side housing and an anti-impeller-side housing, an assembly formed by assembling an impeller and an electric motor, and a fan casing. FIG. 10 is an exploded perspective view of an assembly formed by assembling an impeller-side housing and an anti-impeller-side housing, and an assembly formed by assembling an impeller, an electric motor, and a fan casing. 1 is a perspective view of the appearance of an electric blower 200 according to an embodiment of the present invention. FIG. 13 is an enlarged perspective view of the portion XIV in FIG. 12 as viewed from the impeller-side housing 212 side. FIG. 13 is an enlarged view of a portion XIV in FIG. 12.

The following describes an embodiment of the present invention with reference to the drawings. Note that, as a general rule, identical elements are assigned the same reference numerals throughout the drawings. Furthermore, descriptions of parts with identical functions will be omitted. Note that the configurations described below are merely examples, and it is not intended that the embodiments of the present invention be limited to the specific embodiments below.

Embodiments of the present invention will now be described with reference to the drawings. Figure 1 is a perspective view showing an electric vacuum cleaner 100 according to an embodiment of the present invention stored in a charging base. In Figure 1(a), the electric vacuum cleaner 100 is stored in a stick state in the charging base.

The electric vacuum cleaner 100 can be used in a variety of different modes, such as handheld mode and stick mode, for cleaning. The charging stand 70a, which houses the electric vacuum cleaner 100 in stick mode, is composed of a base member 71, three stand members 72, and a holder member 73. The holder member 73 is designed to accept an output plug of an AC adapter for charging the storage battery 3 installed in the electric vacuum cleaner 100; when the electric vacuum cleaner 100 is placed on the charging stand 70a, the output plug is connected to the input jack of the electric vacuum cleaner 100, allowing charging.

The base member 71 has a mounting surface 71a and an extension portion 71b. The mounting surface 71a is a generally rectangular plate-shaped portion. The extension portion 71b is a generally truncated cone-shaped portion. The extension portion 71b is arranged so as to be generally perpendicular to the mounting surface 71a. The central axis of the extension portion 71b is located approximately in the center of the mounting surface 71a in the left-right direction and approximately 3/4 of the way up in the front-to-back direction.

In addition, in Figure 1(b), the vacuum cleaner 100 is stored in a handheld state on the charging base. In this state, the charging base 70b stores the vacuum cleaner 100 in a handheld state, and unlike the charging base 70a, it is configured with one stand member 72, a base member 71, and a holder member 73, omitting two stand members 72. Note that the user can also remove three stand members 72 for compact storage, or remove one and adjust the height to make it easier to access. The pillar of the charging base, made up of the stand member 72 and the holder member 73, is formed on the axis of the dust case 2, so the vacuum cleaner 100 can be placed on the charging base and held stably when charging.

Figure 2 is an exploded view of an electric vacuum cleaner 100 according to an embodiment of the present invention. As shown in Figure 2, the electric vacuum cleaner 100 is configured to include a vacuum cleaner main body 1, a dust case 2 (dust collection device), a storage battery 3 (power storage device), and an airtight member 90.

The vacuum cleaner body 1 is composed of a main body 10, a motor case 11, and a handle 12.

The main body 10 is formed with a connection port 10a (suction port) to which the extension tube 300 (see Figure 1) or standard suction nozzle 400 (see Figure 1) can be connected. This connection port 10a is molded from the same resin as the main body 10, motor case 11, handle 12, etc. The connection port 10a has a roughly circular opening and is formed facing forward. Attachments such as the crevice/brush switching nozzle 110, extension tube 300, standard suction nozzle 400, compact suction nozzle 600, and broom-type suction nozzle 700 can be connected to the connection port 10a.

The dust case 2 is removably attached to the main body 10, and is equipped with an intake pipe 14 (see Figure 3) that sends dust-containing air sucked in through the connection port 10a into the dust case 2.

The motor case 11 houses the electric blower 200 (see Figure 5) and the main body circuit board (not shown). A circular suction port 11a is formed on the front of the motor case 11, through which clean air is drawn in after dust has been collected in the dust case 2. Also, on the front of the motor case 11, below the suction port 11a, a main body terminal section 17 is provided for connection to the charging bases 70a and 70b.

The handle 12 is located on the rear side of the main body 10 and is formed in a roughly arc shape. By making the handle 12 roughly arc-shaped, the user can grip the handle 12 in a position that is most convenient for them depending on the situation.

The handle portion 12 is also provided with a locking member 13 for locking the storage battery 3. This locking member 13 is button-shaped and supported so that it can swing. An operation button 12a is provided on the top surface of the handle portion 12. The operation button 12a consists of three buttons, for example, "strong," "standard," and "off."

Furthermore, a release button 18 is provided at the upper front end of the handle 12, which is operated when removing accessories such as the extension tube 300 (see Figure 1). By pressing this release button 18, the lock between the main body 10 and the accessory is released, allowing the accessory to be removed from the main body 10.

An airtight seal member 90 is attached to the front end of the main body 10. This airtight seal member 90 has a substantially circular cylindrical body 91. This cylindrical body 91 has a brush portion 90s with soft bristles attached at the tip. The brush portion 90s is attached at multiple locations with bristles spaced apart and is made of an elastically deformable (flexibly deformable) material such as nylon resin. Attaching this airtight seal member 90 to the connection port 10a of the vacuum cleaner main body 1 allows for the sweeping of dirt from the surface to be cleaned, and pressing the tip of the airtight seal member 90 against the floor surface improves suction power. Furthermore, by forming the connection portion 91b from a hard material, the airtight seal member 90 can be attached stably to the main body 10 without falling off.

In this embodiment, the brush portion 90s is formed from a brush such as nylon bristles, but this is not limited to this. For example, the tip may be formed in a ring shape from soft resin. That is, the cylindrical body 91 is formed by integrally molding two different members, the elastic portion 91a and the connecting portion 91b. The elastic portion 91a is made of an elastically deformable (flexibly deformable) material such as an elastomer. This allows the entire brush portion 90s of the airtight member 90 to be in close contact with the floor surface, improving suction power compared to when it is not in close contact.

The entire cylindrical body 91 may be made of the same material as the connecting portion 91b, and the tip of the cylindrical body 91 may be provided with a ring of electrostatically planted short bristles. Even with such electrostatically planted bristles, like elastomer, the tip of the airtight member 90 can be brought into close contact with the floor surface, improving suction power.

A horizontally elongated mating groove 10b is formed on the upper surface of the connection port 10a of the main body 10. A protrusion (not shown) is formed at the base end of the connection portion 91b, which engages and locks into the mating groove 10b.

The main body 10 also has a light-emitting element 10c (see Figure 2) located above the connection port 10a. This light-emitting element 10c is configured to emit light forward, i.e., toward the surface to be cleaned (such as a floor).

When the airtightness maintaining member 90 is attached to the vacuum cleaner body 1, the light-emitting element 10c is located above the airtightness maintaining member 90. In other words, the outer diameter of the airtightness maintaining member 90 is set so that the light-emitting element 10c is located outside the airtightness maintaining member 90.

The storage battery 3 supplies power to the electric blower 200 (see Figure 5) and is composed of a secondary battery such as a lithium-ion or nickel-metal hydride battery. The storage battery 3 has a roughly cylindrical case 3a made of synthetic resin, and can be attached to and detached from the main body 10 by sliding the case 3a back and forth.

A terminal portion 3b that connects to the main body portion 10 is provided on the top surface of the case 3a. A slide groove 3c that is slidably supported by the main body portion 10 is formed on the top surface of the case 3a in front of the terminal portion 3b. Slide rails 3d, 3d that are slidably supported by the main body portion 10 are also formed on the top surface of the case 3a protruding to the left and right sides behind the terminal portion 3b.

In addition, an inlet hole 3e is formed on the front surface of the case 3a on one side (left side) in the left-right direction (width direction) through which cooling air is introduced to cool the storage battery 3. This inlet hole 3e is elongated in the vertical direction.

In addition, a discharge hole 3f is formed on the front surface of the case 3a on the other (right) side in the left-right direction (width direction) through which air is discharged after cooling the storage battery 3. This discharge hole 3f is formed to have a shape symmetrical to the aforementioned inlet hole 3e.

In addition, a locking recess 3g is formed on the back of the case 3a, into which the locking member 13 fits to lock it to the main body 10.

Figure 3 is a view taken in the direction of arrow III in Figure 2. As shown in Figure 3, the dust case 2 is a cyclone type that separates dust-laden air sucked in through the inlet pipe 14 into dust and air and collects the dust. The dust case 2 is disposed in front of the motor case 11 with its axial direction running in the front-to-rear direction and has a roughly cylindrical storage section 2a. The storage section 2a has an opening on its front surface. The top surface (side surface) of the dust case 2 is formed with a roughly rectangular inlet 2b (see Figure 2) that connects to the inlet pipe 14. The dust-laden air that flows into this inlet 2b becomes a swirling flow, and centrifugal force acts on the dust, separating the dust and air within the dust case 2. The dust-separated air is then discharged from the rear (back) of the dust case 2.

The front of the dust case 2 is fitted with a lid 2c, which opens and closes when disposing of dust accumulated inside the dust case 2. This lid 2c is supported rotatably relative to the storage compartment 2a via a hinge 2d, and closing the lid 2c blocks the storage compartment opening. A lid locking mechanism 2e is provided on top of the lid 2c to unlock the lid 2c.

An exhaust port 16 is provided at the bottom of the motor case 11. Although not shown, this exhaust port 16 has multiple slits 16a along the front-to-rear direction, and the multiple slits 16a are aligned vertically. Exhaust ports 16 are provided on both the left and right sides. A cover member 16b is provided to cover either the left or right side of this exhaust port 16. The dust case 2, motor, and storage battery 3 are arranged in a straight line in the longitudinal direction of the vacuum cleaner body, or coaxially. The cover member 16b slides around the axis of the motor case 11 or dust case 2 as a rotation center, allowing it to selectively open either the left or right exhaust port 16. The outer shell surface of the cover member 16b is formed to be approximately the same plane as the motor case 11.

Figure 4 is an external perspective view of a vacuum cleaner 100 according to an embodiment of the present invention. As shown in Figure 4, the vacuum cleaner 100 has a dust case 2 attached below the main body 10 and in front of the motor case 11. In this case, when the dust case 2 is attached to the vacuum cleaner body 1, the lid locking mechanism 2e is positioned on the vacuum cleaner body 1 side. This is because if the lid locking mechanism 2e were located on the opposite side (outside), there is a risk that the lid locking mechanism 2e would be released during cleaning. However, by positioning the lid locking mechanism 2e on the vacuum cleaner body 1 side, this malfunction can be prevented. For example, when cleaning under a sofa or bed in stick mode, the vacuum cleaner body 1 may be brought close to the floor surface. In this case, if the lid locking mechanism 2e were located on the front side, there is a risk that the lid locking mechanism 2e would come into contact with the floor surface and be released. The positions of the lid locking mechanism 2e and the hinge portion 2d are not limited to this; they may be located on the left or right side of the vacuum cleaner body 1.

The dust case 2 is also provided with a detachable maintenance brush 2s (see Figures 2 and 3). This maintenance brush 2s is positioned in a location that is difficult to see from the outside when the dust case 2 is attached to the vacuum cleaner body 1. This makes it difficult for the maintenance brush 2s to come off during operation, and there is no need to store the maintenance brush 2s in a location separate from the electric vacuum cleaner 100.

Next, the configuration of the electric blower 200 will be described with reference to Figures 5 to 14. Figure 5 is a cross-sectional view of the electric blower 200 according to an embodiment of the present invention, taken along the rotational axis. Figure 6 is a side view, partially cross-sectional, of the right half of the impeller-side housing 212 according to an embodiment of the present invention. Figure 7 is a perspective view, partially cross-sectional, of the anti-impeller-side housing 213 according to an embodiment of the present invention. Figure 8 is a cross-sectional view, partially cross-sectional, of the fan casing 230 according to an embodiment of the present invention, taken along the axial direction. Figure 9 is an exploded perspective view of the electric blower 200 according to an embodiment of the present invention. Figure 10 is an exploded perspective view of an assembly of the impeller-side housing and the anti-impeller-side housing, an assembly of the impeller and the electric motor, and the fan casing. Figure 11 is an exploded perspective view of an assembly of the impeller-side housing and the anti-impeller-side housing, and an assembly of the impeller, the electric motor, and the fan casing. Figure 12 is an external perspective view of the electric blower 200 according to an embodiment of the present invention. Figure 13 is an enlarged perspective view of section XIV in Figure 12 as viewed from the impeller-side housing 212 side. Figure 14 is an enlarged view of section XIV in Figure 12.

In Figure 5, typical air flows are shown on the left side only by solid arrows α1 and dotted arrows α2.

The electric blower 200 is housed in the electric vacuum cleaner 100 shown in Figure 1 with the impeller 211 facing the standard suction nozzle 400 at the bottom.

The electric blower 200 has an electric motor section 250 configured radially inward of the blower section 210.

The blower section 210 comprises, from upstream of the intake airflow, an impeller 211 (a rotating blade), a first axial diffuser vane 212a (impeller-side diffuser vane) on the impeller side, and a second axial diffuser vane 213a (anti-impeller-side diffuser vane). The diffuser vanes (first axial diffuser vane 212a, second axial diffuser vane 213a) are provided in housings (impeller-side housing 212, anti-impeller-side housing 213) that cover the outer periphery of the electric motor section 250. An exhaust port 214 is provided downstream of the second axial diffuser vane 213a.

The impeller 211 is rotated by the electric motor unit 250 and its outer periphery is covered by the fan casing 230. The structure of the fan casing 230 will be described later.

As shown in Figures 6 and 9, the impeller-side housing 212 has an inner annular portion 212b and an outer annular portion 212c arranged radially outward (outer periphery) of the inner annular portion 212b, and a first axial-flow diffuser vane 212a is arranged between the inner annular portion 212b and the outer annular portion 212c. Multiple first axial-flow diffuser vanes 212a are arranged at an angle to the axial direction.

As shown in Figures 7 and 9, the anti-impeller housing 213 has an inner annular portion 213b and an outer annular portion 213c arranged radially outward (outer periphery) of the inner annular portion 213b, and second axial diffuser vanes 213a are arranged between the inner annular portion 213b and the outer annular portion 213c. Multiple second axial diffuser vanes 213a are arranged so that the upstream side is inclined with respect to the axial direction and the downstream side is aligned with the axial direction.

As shown in Figures 5 and 9, the impeller-side housing 212 having the first axial diffuser vanes 212a is fixed to the impeller-side motor housing 251 using screws 270.

The anti-impeller housing 213, which has a second axial diffuser vane 213a arranged on the anti-impeller side (the side farther from the impeller 211), is located downstream of the impeller housing 212 (on the exhaust port 214 side).

The electric motor section 250 is located radially inward of the impeller-side housing 212 and the anti-impeller-side housing 213. The impeller-side housing 212 is positioned to cover the impeller-side motor housing 251, and the anti-impeller-side housing 213 is positioned to cover the anti-impeller-side motor housing 252. A stator and a rotor are provided inside the motor housings (impeller-side motor housing 251, anti-impeller-side housing 213).

As shown in Figures 5 and 9, the impeller-side motor housing 251 has the same shape as the anti-impeller-side motor housing 252 and is provided with multiple radially openings 251a, 252a on its outer periphery. The anti-impeller-side motor housing 252 is provided with an axially extending opening 252b. Six radially openings 251a, 252a are arranged circumferentially on the outer periphery of each motor housing. The openings 251a of the impeller-side motor housing 251 and the openings 252a of the anti-impeller-side motor housing 252 are arranged on the stator core 253 so as not to overlap in the axial direction. The openings 251a, 252a of each motor housing are arranged so as to overlap in the axial direction with the axial ends of the coils. The radial openings of the motor housing are uniformly arranged in the circumferential direction, and the number of openings and the number of blades of the second axial diffuser vanes 213a have a greatest common denominator of three. In other words, the same flow field can be introduced into the openings 252a at three locations in the circumferential direction, making it possible to reduce the circumferential temperature distribution. Note that the greatest common denominator should be greater than 1, preferably greater than 3, or equal to the number of openings.

The impeller-side motor housing 251 holds the bearing 280 on the impeller 211 side in the axial direction of the electric motor unit 250. The anti-impeller-side motor housing 252 holds the bearing 281 on the anti-impeller side in the axial direction of the electric motor unit 250.

The second flow path 216 passes through the radial opening 252a of the anti-impeller side motor housing 252, the opening 251a between the interior of the motor and the impeller side motor housing 251, and between the outer periphery of the impeller side motor housing 251 and the inner annular portion 212b of the impeller side housing 212.

A first flow path 215 is provided on the side of the electric blower 200, passing through the impeller 211, first axial diffuser vane 212a, and second axial diffuser vane 213a. The first flow path 215 is a flow path through which air drawn in from the standard air intake 400 (see Figure 1) flows.

The first flow path 215 and the second flow path 216 converge at the axial end 213d of the inner annular portion 213b of the anti-impeller housing 213. The axial end 213d is located approximately halfway along the axial dimension of the second axial diffuser vane 213a. By converging the first flow path 215 and the second flow path 216 at the axial end 213d, the main flow of the second axial diffuser vane 213a creates a flow within the second flow path 216 due to the Venturi effect, and cooling air is drawn into the motor through the opening 252a and the axial opening 252b of the anti-impeller motor housing 252. This improves the cooling performance of the motor section 250. However, the opening 252a of the anti-impeller motor housing 252 does not necessarily need to be machined in order to allow cooling of the motor interior.

The axial end 213d may be located at or beyond approximately half the axial dimension of the second axial diffuser vane 213a, and may extend to the trailing edge of the vane. In order to generate cooling air using the Venturi effect, it is desirable for it to be located closer to the impeller in the axial direction than the opening 252a.

The second flow path 216 is located radially inward from the first flow path 215. The motor housing 252 on the side opposite the impeller has an axial opening 252b and a radial opening 252a. By enlarging these openings, the amount of air generated by the Venturi effect can be increased, allowing the inside of the motor to be cooled more efficiently as it passes through the second flow path 216.

In addition, the opening 252a of the anti-impeller side motor housing 252 is located radially inward from the inner annular portion 213b of the anti-impeller side housing 213, making it easier to ensure the flow path area of the second flow path 216 and allowing for more efficient cooling of the inside of the motor.

A portion of the motor winding protrudes from opening 252b and is electrically connected to a drive circuit (not shown). The openings in the motor housings (impeller-side motor housing 251, anti-impeller-side motor housing 252) may be square, round, or have other shapes.

In this embodiment, the impeller 211 has a metal sleeve 283 covered by a hub plate 211a made of thermoplastic resin. The impeller 211 is fixed by a fixing nut 284 threaded onto a female thread formed on the end of the rotating shaft 255. The impeller 211 in this embodiment is a mixed flow impeller, but it may also be a centrifugal or axial flow impeller.

Next, the configuration of the electric motor unit 250 will be described. As shown in Figures 5 and 9, the electric motor unit 250 includes a rotor core 254 (rotor) and a stator core 253 (stator) arranged on the outer periphery of the rotor core 254.

The rotor core 254 is housed within two motor housings and fixed to the rotating shaft 255.

A coil (winding) 256 is wound around the stator core 253. The coil 256 is electrically connected to a drive circuit (not shown) provided in the electric blower 200. Copper wire is used for the coil 256, but aluminum wire or a composite wire with a copper coating around the aluminum wire may also be used.

The rotor core 254 is made of a rare earth bonded magnet. Rare earth bonded magnets are made by mixing rare earth magnetic powder with an organic binder. Examples of rare earth bonded magnets that can be used include samarium iron nitrogen magnets and neodymium magnets. The rotor core 254 is either integrally molded with or fixed to the rotating shaft 255. The operating rotational speed of the electric blower 200 is 50,000 to 200,000 cycles/min.

In this embodiment, a permanent magnet is used for the rotor core 254, but this is not limited to this, and a reluctance motor, which is a type of commutatorless motor, may also be used.

A bearing 280 is provided between the impeller 211 and the rotor core 254. A bearing 281 is also provided on the opposite side of the impeller 211. The rotating shaft 255 is rotatably supported by the bearing 280 located on one side and the bearing 281 located on the other side.

The impeller-side motor housing 251, which is closer to the impeller 211, supports the bearing 280, while the anti-impeller-side motor housing 252, which is farther from the impeller 211, supports the bearing 281. The motor housing is made of metal, and using an aluminum alloy as the material allows for improved cooling through heat conduction and weight reduction. The motor housing may also be made of resin instead of metal, and if made of resin, providing a metal support between the bearing and the motor housing can promote cooling of the bearing. The motor housing may also be made of either aluminum alloy or steel.

A spacer 285 is installed on the rotor core 254 side of bearings 280 and 281 to position the bearings axially (Figure 5).

The impeller-side motor housing 251, located closer to the impeller 211, and the anti-impeller-side motor housing 252, located further from the impeller 211, are identical in shape and are positioned so that the stator core 253 is sandwiched between them in the axial direction. The outer periphery of the stator core 253 overlaps the inner wall of the motor housing in the axial direction, and they are assembled by adhesive or press-fitting. The stator core 253 contacts the two motor housings and has an exposed portion 253a exposed from the motor housing at approximately the center of the stator core 253. This stator core 253 and motor housing structure allows heat generated by the stator core 253 to be cooled by thermal conduction through the impeller-side motor housing 251 and the anti-impeller-side motor housing 252, as well as forced cooling through the exposed portion 253a, enabling high heat density and low-loss cooling. The multiple openings 251a, 252a provided around the motor housing circumferentially may be located at the same or different circumferential positions. By using a motor housing with the same structure, we have achieved both low costs and improved cooling performance.

The circumferential positions of the first axial diffuser vane 212a and the second axial diffuser vane 213a will now be explained. The outer periphery of the impeller-side housing 212 is provided with a first protrusion 220, a second protrusion 224, and a third protrusion 221 that protrude radially outward at three locations in the circumferential direction.

The second protrusion 224 is positioned at a position offset from the circumferential extension and axial extension of the first protrusion 220. The third protrusion 221 is positioned at a position offset from the circumferential extension of the first protrusion 220, but overlaps with the axial extension.

The outer periphery of the anti-impeller side housing 213 (outer annular portion 213c), which is the side farthest from the impeller 211, has claw portions 222 formed at three circumferential locations. The claw portions 222 have insertion openings 222a formed therein, into which the third protrusions 221 are inserted. Furthermore, the inside of the anti-impeller side housing 213 (outer annular portion 213c) has a mounting portion 223 formed therein that extends circumferentially and abuts against the end of the outer annular portion 212c of the impeller side housing 212, on which the impeller side housing 212 is mounted.

The number of blades on the first axial diffuser vanes 212a, the number of claws 222 at the end of the anti-impeller housing 213, and the number of third protrusions 221 on the impeller-side housing 212 are determined so that the greatest common divisor of the number of blades and the third protrusions 221 is 3. In this way, the circumferential positions of the first axial diffuser vanes 212a and the second axial diffuser vanes 213a are set to predetermined circumferential positions, improving mass productivity. Note that the greatest common divisor of the number of blades and the third protrusions 221 may be greater than 1, but using the number of protrusions determines the circumferential position of each diffuser vane, optimizing mass productivity during assembly.

Next, the structure of the fan casing 230 will be described. The fan casing 230 has an intake section 231 that draws in air as the impeller 211 rotates, an inclined section 232 formed so that the flow path expands downstream from the intake section 231, and an outer wall section 233 that extends axially from the end of the inclined section 232.

The outer wall portion 233 has an L-shaped notch 234 formed in it, which protrudes partially toward the side where it connects to the impeller-side housing 212 and is cut out from the side where it connects to the impeller-side housing 212 toward the impeller side, and extends circumferentially around the fan casing 230. The notch 234 is formed in three locations around the circumference of the outer wall portion 233. Furthermore, the notch 234 on the impeller-side housing side (lower side) is provided with an axial fixing portion 236 that extends circumferentially.

Furthermore, the fan casing 230 has an abutment portion 235 extending circumferentially formed at a position radially inward (inner peripheral side) of the outer wall portion 233. The abutment portion 235 abuts against the impeller-side end of the outer annular portion 212c of the impeller-side housing 212 when the fan casing 230 and the impeller-side housing 212 are combined.

Next, we will explain how to assemble the electric blower 200.

As shown in Figure 9, the impeller-side housing 212 is positioned to cover the impeller-side motor housing 251 of the electric motor, which is assembled separately, and is fixed to the impeller-side motor housing 251 using screws 270.

Next, the impeller 211 is fixed to the rotating shaft 255. The impeller 211 is inserted onto the rotating shaft 255 of the electric motor, and a fixing nut 284 is attached to the end, and the impeller 211 is fixed to the rotating shaft 255 (Figure 10).

Next, the outer annular portion 212c of the impeller-side housing 212 is inserted into the inner periphery of the outer wall portion 233 of the fan casing 230, connecting the impeller-side housing 212 and the fan casing 230.

To connect the impeller-side housing 212 and the fan casing 230, the notch 234 of the fan casing 230 is aligned with the first protrusion 220 formed on the outer periphery of the impeller-side housing 212, and the first protrusion 220 is inserted through the notched portion of the notch 234 on the impeller-side housing 212 side. When the first protrusion 220 is inserted into the notch 234, the abutment portion 235 of the fan casing 230 abuts against the impeller-side end of the outer annular portion 212c that forms part of the impeller-side housing 212, restricting axial movement. The fan casing 230 is then rotated relative to the impeller-side housing 212 (to the left in Figure 11, in the direction of the arrow in Figure 13) until the first protrusion 220 and the axial fixing portion 236 are positioned so that they overlap in the axial direction. Additionally, the first protrusion 220 abuts against the end of the notch 234. This restricts movement of the fan casing 230 in either the axial or circumferential direction, connecting the fan casing 230 to the impeller-side housing 212.

Next, we will explain the means for preventing the fan casing 230 from rotating in the direction of removal using Figures 13 and 14.

In addition to the first protrusion 220, the outer periphery of the impeller-side housing 212 is provided with second protrusions 224 at three locations in the circumferential direction.

The second protrusion 224 has a first inclined portion 224a that gradually becomes higher in the rotation direction (protrudes radially outward) when the fan casing 230 is rotated and fixed. In other words, the second protrusion 224 has a first inclined portion 224a that is inclined so that the amount of protrusion radially outward increases as it moves from the first protrusion 220 side toward the opposite side of the first protrusion in the circumferential direction.

In addition, the outer wall portion 233 (outer periphery) of the fan casing 230 is provided with a circumferential fixing portion 237 that abuts against the second protrusion portion 224 when the fan casing 230 is rotated in the circumferential direction, thereby restricting the circumferential rotation of the fan casing 230.

The inner surface of the circumferential fixing portion 237 is provided with a second inclined portion 237a that gradually becomes higher in the rotation direction (protrudes radially inward) when the fan casing 230 is rotated and fixed. In other words, the inner surface of the circumferential fixing portion 237 is provided with a second inclined portion 237a that is inclined so that the amount of protrusion radially inward increases as it moves from the side opposite the first protrusion toward the first protrusion 220 in the circumferential direction.

Then, when the first protrusion 220 is inserted into the notch 234 of the fan casing 230 and the fan casing 230 is rotated in the direction of the arrow shown in Figure 13, the axial fixing portion 236 moves to a position where it overlaps with the first protrusion 220 in the axial direction, and the circumferential fixing portion 237 moves over the first inclined portion 224a of the second protrusion 224, causing the end of the circumferential fixing portion 237 to abut against the end of the second protrusion 224 (Figure 14). The abutment between the end of the circumferential fixing portion 237 and the end of the second protrusion 224 restricts circumferential movement of the fan casing 230.

Next, the motor assembly integrated with the fan casing 230 is fixed to the anti-impeller side housing 213. To fix the motor assembly to the anti-impeller side housing 213, the third protrusion 221 of the impeller side housing 212 is aligned with the claw portion 222 of the anti-impeller side housing 213, and the third protrusion 221 is inserted into the insertion opening 222a of the claw portion 222. When the third protrusion 221 is inserted into the insertion opening 222a of the claw portion 222, the end of the outer annular portion 212c of the impeller side housing 212 abuts against the mounting portion 223 of the anti-impeller side housing 213, connecting the impeller side housing 212 and the anti-impeller side housing 213.

In this embodiment, the first protrusion 220 of the impeller-side housing 212 is inserted into the notch formed in the fan casing 230 to connect the fan casing 230 and the impeller-side housing 212, making it possible to easily stabilize the connection between the fan casing 230 and the impeller-side housing 212.

Furthermore, according to this embodiment, the second protrusion 224 and circumferential fixing portion 237 are provided to restrict circumferential rotation of the fan casing 230, thereby preventing the connection between the fan casing 230 and the impeller-side housing 212 from being released.

Furthermore, according to this embodiment, an abutment portion 235 extending circumferentially is formed at a radially inner position on the outer wall portion 233 of the fan casing 230, and this abutment portion 235 is designed to abut against the impeller-side end of the outer annular portion 212c of the impeller-side housing 212. This stabilizes the positions of the impeller-side housing 212 and the fan casing 230, preventing the impeller 211 from locking and causing rotation problems.

The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and are not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations.

1...vacuum cleaner body, 2...dust case, 2a...storage section, 2b...inlet, 2c...lid, 2d...hinge section, 2e...lid lock mechanism, 2s...maintenance brush, 3...storage battery, 3a...case, 3b...terminal section, 3c...slide groove, 3d...slide rail, 3e...inlet hole, 3f...exhaust hole, 3g...lock recess, 10...main body section, 10a...connection port, 10b...fitting groove, 10c...light-emitting element, 11...motor case section, 11a...suction port, 12...handle section, 12a...operation button, 13...locking member, 14...inlet pipe, 16...exhaust port, 16a...slit, 16b...case Bar member, 17...main body terminal portion, 18...release button, 50...operating rotation speed, 70a...charging base, 70b...charging base, 71...base member, 71a...placing surface, 71b...extension portion, 72...stand member, 73...holder member, 90...airtightness maintaining member, 90s...brush portion, 91...cylindrical body, 91a...elastic portion, 91b...connection portion, 100...electric vacuum cleaner, 110...gap/brush switching nozzle, 200...electric blower, 210...blower portion, 211...impeller, 211a...hub plate, 212...impeller-side housing, 212a...first axial flow diffuser blade, 212b...inner Annular portion, 212c...outer annular portion, 213...opposite-impeller-side housing, 213a...second axial-flow diffuser vane, 213b...inner annular portion, 213c...outer annular portion, 213d...axial end portion, 214...exhaust port, 215...first flow path, 216...second flow path, 220...first protrusion, 221...third protrusion, 222...claw portion, 222a...insertion opening, 223...mounting portion, 224...second protrusion, 224a...first inclined portion, 230...fan casing, 231...suction portion, 232...inclined portion, 233...outer wall portion, 234...notched portion, 235...contact portion, 236...axial Circumferential fixing portion, 237...circumferential fixing portion, 237a...second inclined portion, 250...motor portion, 251...impeller side motor housing, 251a...opening, 252...anti-impeller side motor housing, 252a...opening, 252b...opening, 253...stator core, 253a...exposed portion, 254...rotor core, 255...rotating shaft, 256...coil (winding), 270...screw, 280...bearing, 281...bearing, 283...sleeve, 284...fixing nut, 285...spacer, 300...extension tube, 400...standard suction nozzle, 600...small suction nozzle, 700...broom-type suction nozzle.

Claims (5)

An electric blower comprising: an electric motor section having a stator and a rotor within a motor housing; an impeller rotationally driven by the electric motor section; a housing covering an outer periphery of the electric motor section and having diffuser blades; and a fan casing connected to the housing and covering the impeller,
The housing is provided on its outer periphery with a first protrusion protruding radially outward and a second protrusion protruding radially outward and disposed at a position offset from a circumferential extension line and an axial extension line of the first protrusion ,
The fan casing is formed with an L-shaped notch portion that is cut out from the side connected to the housing toward the impeller side and extends in the circumferential direction of the fan casing , and a circumferential fixing portion that restricts rotation of the fan casing in the circumferential direction ,
an electric blower characterized in that after the first protrusion is inserted from the side of the notch that connects to the housing, the fan casing is rotated circumferentially to move the first protrusion to a position that extends circumferentially from the notch , thereby connecting the fan casing and the housing, and the second protrusion is abutted against the circumferential fixing portion to restrict circumferential rotation of the fan casing . In claim 1,
the housing includes an inner annular portion and an outer annular portion disposed on an outer peripheral side of the inner annular portion, the diffuser vanes being disposed between the inner annular portion and the outer annular portion,
an inner peripheral side of the fan casing, the inner peripheral side of which is provided with a contact portion that contacts the impeller-side end of the outer annular portion; In claim 1 ,
An electric blower characterized in that the second protrusion portion is provided with a first inclined portion that is inclined so that the amount of protrusion that protrudes radially outward increases as the second protrusion portion moves from the first protrusion portion side toward the opposite side to the first protrusion portion in the circumferential direction. In claim 3 ,
an electric blower, characterized in that the inner surface of the circumferential fixing portion is provided with a second inclined portion that is inclined so that the amount of protrusion toward the radially inward direction increases as the circumferential direction moves from the side opposite the first protrusion portion toward the first protrusion portion. An electric vacuum cleaner comprising a vacuum cleaner body having a dust case and an electric blower, and an attachment connected to the vacuum cleaner body,
5. An electric vacuum cleaner, wherein the electric blower is the electric blower according to any one of claims 1 to 4 .