TWI460352B - Electric blower and equipped with its electric vacuum cleaner - Google Patents

Description

Electric blower and electric vacuum cleaner equipped therewith

The present invention relates to an electric blower including a fan having a shape that is twisted from an inner edge to an outer edge, and an electric vacuum cleaner provided therewith.

The conventional electric blower is also shown, for example, in the following Patent Document 1, but generally consists of a shroud, a main plate disposed at an opposite position thereof, and a plurality of blades disposed between them. The blade system causes the shroud side to be inclined more than the hub side, and the air volume and the vacuum pressure are obtained by rotating at a high speed.

In particular, in Patent Document 1, it is described that the blade is sandwiched between the front cover and the rear cover (hub) and is fixed by riveting, and when comparing the radius of curvature of the blade near the suction port, The front shroud side is inclined more than the rear shroud side, and in the inner peripheral side, the front shroud side is inclined toward the rotational direction, and in the outer peripheral side, the rotary fan of the electric blower slightly perpendicular to the rear shroud.

Further, a configuration of a conventional fan similar to a conventional electric blower is disclosed, for example, in Patent Document 2 below. In the conventional fan, a blade having a plurality of sheets spanning between the hub and the outer peripheral portion of the shroud is formed, and a fan suction port is formed in a central portion of the shroud so that the shroud side in the rear edge portion of each of the vanes The impeller of the centrifugal fan whose position of the joint portion is deviated from the position of the hub-side joint portion by a certain amount in the reverse rotation direction is characterized in that the hub-side vane exit angle and the shroud-side vane exit angle in the trailing edge portion of each of the vanes are equal .

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Patent No. 2775501 (Japanese Patent Laid-Open No. Hei 3-151598)

[Patent Document 2] Patent No. 2730396 (Japanese Patent Laid-Open No. Hei 4-120753)

In the conventional electric blower (Patent Document 1), the detailed blade angle distribution is not adjusted for the airflow at the inlet, and the flow inside the impeller is likely to cause peeling and backflow, which causes energy loss (efficiency). In particular, the suction port of the electric blower suppresses the leakage airflow caused by the pressure difference between the vane suction port and the impeller exit by the rotating blower and the inlet ring for guiding the suction airflow. Therefore, at the suction port, a step is generated at the joint between the rotating body and the stationary body. Considering the stepped airflow and the leakage airflow, in order to adjust the matching with the blade inlet angle and the load distribution of the blade, it is necessary to understand the phenomenon inside the blade, and Into the best. That is, in the case of an inlet leak, it is necessary to match the leak to adjust the blade angle distribution, and to optimize the load distribution of the blade to suppress peeling and backflow, thereby achieving high efficiency. In addition, for the airflow at the inlet, the detailed fan blade angle distribution is not adjusted. In the vicinity of the suction port, the inclination of the blade of the impeller does not coincide with the inflow direction of the air, and the air touches the side of the fan, and the impact loss becomes larger. After that.

Further, in the above-described electric blower (Patent Document 1), when the blade is viewed from the axial direction, the inclination of the blade to the main plate is large, and in the assembly process of the sheet metal, the blade or the riveting is liable to collapse due to compression or the like. There is a problem in assembly.

Further, in the conventional electric blower (Patent Document 1), on the inner peripheral side (inflow side), although the front shroud side is inclined in the rotational direction, the outer peripheral side (outflow side) is slightly perpendicular to the rear shroud, On the outer peripheral side (outflow side), the flow of air becomes uneven from the front shroud to the rear shroud, that is, from the front shroud to the rear shroud, the pressure distribution or the velocity distribution becomes uneven, and the energy loss becomes large. Hey.

Further, in the conventional fan (Patent Document 2), in order to efficiently decelerate the airflow flowing out of the fan, a stationary blade (for example, a diffusion wing) provided downstream of the fan is formed, and the trailing edge portion of the blade is placed. The position of the shroud-side joint portion is located in the impeller of the centrifugal fan that is offset from the hub-side joint portion by a certain amount in the reverse rotation direction, and does not seek to match the airflow of the stationary wing, and the airflow is easily peeled off in the wing of the stationary wing. And countercurrent, which is the cause of energy loss (low efficiency).

Accordingly, an object of the present invention is to optimize the shape of the blades in each cross section in the direction of the rotation axis, to suppress the peeling or backflow of the airflow between the blades, or to reduce the average flow velocity of the airflow at the blade outlet, or to suppress the The flow rate distribution from the shroud of the blade outlet to the hub becomes uneven, thereby providing a highly efficient electric blower and an electric vacuum cleaner equipped therewith.

Further, an object of the present invention is to provide an electric blower that can suppress blade compression when the hub and the shroud are riveted and mounted, and an electric vacuum cleaner equipped therewith.

The present invention is characterized in that each of the blades is twisted from the inner edge in the radial direction to the outer edge in the radial direction, and is twisted toward the side of the rotation direction with respect to the direction of the rotation axis, and is again turned toward the direction of the reverse rotation axis. The side of the rotation is twisted.

Alternatively, the present invention is characterized in that each of the vanes has a direction slightly perpendicular to the direction of the rotation axis of the blade in the direction of the direction of the rotation axis of the connection portion with the shroud in the direction of the rotation axis of the blade. Or, in the direction of the rotation axis, the blades are inclined in the direction of the rotation direction, and each of the blades has a direction in which the rotation axis direction is formed, and is inclined toward the rotation direction side with respect to the rotation axis direction in the middle portion in the radial direction of the blade. Part and a portion inclined to the side of the rotation axis toward the reverse rotation direction.

Alternatively, the present invention is characterized in that, viewed from the direction of the rotation axis, the arc-shaped line on the side of the hub-side curved line in the connection portion between the blade and the hub and the shroud-side curved line in the joint portion of the blade and the shroud The inner edge in the radial direction to the outer edge in the radial direction intersect at least at two places.

Alternatively, the present invention is characterized in that an angle of an orthogonal line which is a straight line connecting an arbitrary position of the connecting blade with the axis of the rotating shaft, and an angle formed by the wiring from the direction of the rotating shaft and the outer surface of the curved blade are defined. In the case of the blade angle, the blade angle of the hub side of the blade, particularly in the radially outer edge portion, is smaller than the blade angle of the shroud side of the blade.

According to the present invention, each of the blades is twisted from the inner edge in the radial direction to the outer edge in the radial direction on the side opposite to the direction of the rotation axis, and is twisted toward the side of the reverse rotation axis, and then rotated again toward the direction of rotation. By twisting sideways, the shape of the blade in each cross section in the direction of the rotation axis is made appropriate, and peeling or backflow of the airflow in the flow path between the blades can be suppressed. In addition, the average flow rate of the gas stream at the vane outlet can be reduced. In addition, it is possible to suppress the flow velocity distribution from the shroud of the blade outlet to the hub from becoming uneven. Thereby, the efficiency of the electric blower can be improved, and the suction power of the electric blower and the electric vacuum cleaner equipped therewith can be improved.

According to the present invention, each of the blades is formed in a direction from a direction in which the connecting portion with the hub is formed in a direction of a rotation axis of the connecting portion with the shroud, and is slightly aligned with the direction of the rotating shaft in the outer peripheral portion of the blade in the radial direction, or is rotated. The axial direction is a reference, and is inclined toward the rotation direction side, and each of the blades has a direction in which the rotation axis direction is formed, and a portion inclined to the rotation direction side with respect to the rotation axis direction in the middle portion in the radial direction of the blade The portion in which the direction of the rotation axis is inclined toward the counter-rotation direction side allows the shape of the blade in each cross section in the direction of the rotation axis to be appropriate, and the peeling or backflow of the airflow in the flow path between the blades can be suppressed. In addition, the average flow rate of the gas stream at the vane outlet can be reduced. In addition, it is possible to suppress the flow velocity distribution from the shroud of the blade outlet to the hub from becoming uneven. Thereby, the efficiency of the electric blower can be improved, and the suction power of the electric blower and the electric vacuum cleaner equipped therewith can be improved.

According to the present invention, as viewed from the direction of the rotation axis, the arc-shaped line on the side of the hub-side curved line in the connection portion between the blade and the hub and the side of the blade and the shroud of the blade are in the radial direction. The edge to the outer edge in the radial direction intersects at least at two points, whereby when the blade is riveted and attached to the hub and the shroud, the blade is compressed by the intersection portion, thereby suppressing the blade compression. Further, the shape of the blade in each cross section in the direction of the rotation axis is appropriately adjusted, and the peeling or backflow of the airflow in the flow path between the blades can be suppressed. In addition, the average flow rate of the gas stream at the vane outlet can be reduced. In addition, it is possible to suppress the flow velocity distribution from the shroud of the blade outlet to the hub from becoming uneven. Thereby, the efficiency of the electric blower can be improved, and the suction power of the electric blower and the electric vacuum cleaner equipped therewith can be improved.

According to the present invention, the angle formed by the line connecting the arbitrary position of the connecting blade with the axis of the rotating shaft, and the line connecting the outer surface of the curved blade as viewed from the direction of the rotating shaft is defined as the blade angle. When the blade angle of the hub side of the blade, particularly in the outer edge portion in the radial direction, is smaller than the blade angle of the shroud side of the blade, whereby the shape of the blade in each cross section in the direction of the rotating shaft is optimized, and The stripping or countercurrent of the air flow in the flow path between the blades is suppressed. In addition, the average flow rate of the gas stream at the vane outlet can be reduced. In addition, it is possible to suppress the flow velocity distribution from the shroud of the blade outlet to the hub from becoming uneven. Thereby, the efficiency of the electric blower can be improved, and the suction power of the electric blower and the electric vacuum cleaner equipped therewith can be improved.

The present invention relates to an electric blower comprising: an annular shroud; and a hub disposed facing the shroud; and a vane disposed between the shroud and the hub in a circumferential direction, and a rotating shroud and the hub and the vane The electric blower of the electric unit is characterized in that each of the blades is formed by a flat plate, and each of the blades is twisted from the inner side in the radial direction toward the outer edge in the radial direction, and is rotated from the side in the rotational direction with respect to the direction of the rotation axis. It is twisted to the side of the reverse rotation axis direction, and then twisted again toward the rotation direction side.

The present invention relates to an electric blower comprising: an annular shroud; and a hub disposed facing the shroud; and a vane disposed between the shroud and the hub in a circumferential direction, and a rotating shroud and the hub and the vane The electric blower of the electric unit is characterized in that each of the blades is formed by a flat plate, and each of the blades is formed in a radial direction of the blade from a connection portion with the hub to a direction of a rotation axis of the connection portion with the shroud. The outer edge portion is slightly aligned with the direction of the rotation axis, or is inclined toward the rotation direction side with respect to the rotation axis direction, and each of the blades has a direction in which the rotation axis direction is formed, and is rotated in the middle portion in the radial direction of the blade. The axial direction is a reference, and a portion that is inclined toward the rotation direction side and a portion that is inclined toward the reverse rotation direction side with respect to the rotation axis direction.

The present invention relates to an electric blower comprising: an annular shroud; and a hub disposed facing the shroud; and a vane disposed between the shroud and the hub in a circumferential direction, and a rotating shroud and the hub and the vane The electric blower of the electric part is characterized in that each blade is formed by a flat plate, and the connection between the arc-shaped line on the hub side and the blade and the shield in the connection portion between the blade and the hub is viewed from the direction of the rotation axis. The side curved line of the shroud in the part intersects at least at two points from the inner edge in the radial direction to the outer edge in the radial direction.

The present invention relates to an electric blower comprising: an annular shroud; and a hub disposed facing the shroud; and a vane disposed between the shroud and the hub in a circumferential direction, and a rotating shroud and the hub and the vane The electric blower of the electric motor unit is characterized in that each of the blades is formed by a flat plate, such as an orthogonal line connecting a straight line of an arbitrary position of the connecting blade with an axis of the rotating shaft, and a direction from the rotating shaft direction, and When the angle formed by the wiring outside the curved blade is defined as the blade angle, the blade angle of the hub side of the blade is smaller in the radial inner edge portion and the radial outer edge portion than the blade side of the blade. .

According to the present invention, the shape of the blade in each cross section in the direction of the rotation axis is appropriately adjusted, and the peeling or backflow of the airflow in the flow path between the blades can be suppressed. In addition, the average flow rate of the gas stream at the vane outlet can be reduced. In addition, it is possible to suppress the flow velocity distribution from the shroud of the blade outlet to the hub from becoming uneven. Thereby, the efficiency of the electric blower can be improved, and the suction power of the electric blower and the electric vacuum cleaner equipped therewith can be improved. Further, according to the present invention, by matching the inlet leakage and the blade angular distribution, it is possible to suppress the peeling phenomenon and the backflow phenomenon in the airflow inside the impeller, and it is possible to achieve high efficiency.

Further, when the blade is caulked and attached to the hub and the shroud, the blade is compressed by the intersection portion, whereby the blade compression can be suppressed. Further, according to the present invention, assembly accuracy can be improved by optimizing the riveting position.

Further, according to the present invention, at the inner edge portion of the blade, the blade can be inclined to coincide with the inflow direction of the air, so that the air can be prevented from hitting the side surface of the blade, so that the impact loss is reduced. Further, according to the present invention, it is possible to match the airflow of the stationary blades provided downstream of the rotating blades, and it is possible to reduce the internal loss of the rotating blades and the internal peeling loss of the stationary blades, thereby enabling energy loss. cut back.

Hereinafter, Embodiment 1 and Embodiment 2 of the present invention will be described in detail based on the drawings.

[Example 1]

Hereinafter, an embodiment of the present invention will be described using the drawings.

First, the entire vacuum cleaner will be described using FIG. The structure of the vacuum cleaner body 100 will be described in a cross-sectional view seen from the vacuum cleaner body 100 shown in Fig. 1 . When the hose joint 101 side of the vacuum cleaner main body 100 is the front side of the vacuum cleaner main body 100, the vacuum cleaner main body 100 is provided with the detachable hose joint 101 at the front end. A dust collecting chamber 102 for holding the paper bag 103 is provided on the front side of the vacuum cleaner main body 100, and a motor chamber 105 for accommodating the electric blower 106 is provided on the rear side of the vacuum cleaner main body 100 between the dust collecting chamber 102 and the motor chamber 105. The filter unit 104 for suppressing the flow of dust in the dust collecting chamber 102 into the motor chamber 105 is provided. The dust collection chamber 102 and the motor chamber 105 communicate with each other through the filter portion 104. The dust collecting chamber 102 is provided with a paper bag 103 that can be detachably attached. The opening of the paper bag 103 is in communication with the hose connector 101. When the dust is accumulated in the paper bag 103, the paper bag 103 is inflated, and the bottom of the paper bag 103 is abutted against the filter portion 104 at the bottom on the opposite side. The motor room 105 is provided with an electric blower 106 that generates an attractive force. An anti-vibration rubber 107 (anti-vibration member) for preventing the vibration of the electric blower 106 from being transmitted to the vacuum cleaner main body 100 is provided between the both ends of the front side of the electric blower 106 and the inner wall surface of the front side of the motor chamber 105. The anti-vibration member can also be replaced by a spring instead of rubber. The electric blower 106 is provided with a blower inlet 108 for sucking air at its front end, and a blower outlet 109 for discharging air to the rear side. The blower inlet 108 is open to the filter portion 104. A power cord reel 110 for winding and storing a power cord is provided on the side of the motor chamber 105. Wheels are provided on both sides of the rear side of the electric blower 106. Further, although not shown, a hose is connected to the hose joint 101, and an operation tube for accepting an operation such as ON/OFF of the vacuum cleaner main body 100 is connected to the hose, and the operation tube is connected to an extension that can be stretched and contracted. The tube is connected to the extension tube with an inhalation member. The side of the hose connector 101 (upstream side) is the front side of the vacuum cleaner body 100, and the opposite side is the rear side of the vacuum cleaner body 100. The hose joint 101, the hose, the operation tube, and the extension tube are not essential, and the operation portion or the suction member formed in the operation tube may be directly formed in the electric blower 106. From the above, the vacuum cleaner body 100 is orthogonal to the direction of the front-rear direction of the vacuum cleaner body 100, and is the left-right direction of the vacuum cleaner body 100. The side refers to a side that is more inclined to the left side or the right side than the center of the vacuum cleaner body 100 in the left-right direction. The electric blower 106 may be placed such that the blower inlet 108 is placed in the lateral direction (lateral direction) of the front side of the vacuum cleaner body 100, or may be placed in the longitudinal direction (longitudinal direction) of the blower inlet 108 toward the upper side of the vacuum cleaner body 100.

Next, the air flow in the vacuum cleaner body 100 will be described. The air that has flowed in from the hose joint 101 enters the dust collecting chamber 102. In the first drawing, the paper bag 103 is shown as a dust collecting means, regardless of the material of the paper bag. Further, in the case of the cyclone method, instead of the paper bag 103, it is housed in a cyclone chamber (cyclone type dust box). With the paper bag 103, most of the dust-removed air passes through the filter portion 104, where fine dust is also removed. Thereafter, the airflow flows into the motor chamber 105. The electric blower 106 is suspended in the motor chamber 105 through the vibration-proof rubber 107, and the air that has flowed in from the blower inlet 108 is pressurized by the electric blower 106, and is then discharged from the blower outlet 109.

Next, the electric blower 106 will be described using FIG. The electric blower 106 is composed of a blower 201 (fan portion) for sucking air and a motor 202 (drive portion) for driving the blower 201.

The motor 202 is supported by a motor housing formed by the casing 203 and the rear end cover 204 with a rotating shaft 205, and a rotor 206 is attached to the rotating shaft 205. A stator 207 having a fixed portion is disposed on the outer circumference of the rotor 206. The electrical supply to the rotor 206 of the rotating portion is conveyed by the carbon brush 208 and the rectifier 209 in contact therewith.

The blower 201 is configured such that the impeller 210 that is directly coupled to the rotating shaft 205, and the diffusing vane 211 that is provided on the outer peripheral side of the impeller 210, and the return guide that is disposed opposite the diffuser vane 211 with the partition plate 212 disposed therebetween The 213 is housed in the fan case 214. A plurality of blades (moving blades) are formed on the impeller 210. Since the diffusion wing 211 and the rotating shaft 205 are not connected, they do not rotate. A plurality of blades (static blades) are also formed on the diffusion wings 211. The impeller 210 is in contact with the seal member 216 provided on the side of the fan case 214 in the annular center portion 215, and has a structure for preventing air leakage.

The air corresponding to the electric blower inlet 217 of the blower inlet 108 of Fig. 1 is temporarily passed through the vicinity of the center portion 215, and is then boosted and increased by the impeller 210. Thereafter, the airflow is slightly rotated by 180 degrees by the diffusion wing 211, and flows into the return guide 213. During this process, the airflow is decelerated, and the decelerating portion causes the pressure to rise. The airflow returning to the guide 213 flows into the casing 203 of the motor, and the rotor 206, the stator 207, the carbon brush 208, the rectifier 209, and the like are cooled and exhausted. The axial direction of the rotating shaft 205 slightly coincides with the front-rear direction of the vacuum cleaner body 100. The direction orthogonal to the axial direction is the radial direction with reference to the rotation axis 205.

The outer diameter of the impeller of the electric blower for vacuum cleaner of the present invention is approximately in the range of Φ 60 mm to Φ 120 mm, the blade outlet height is approximately 6 to 12 mm, the thickness of the blade is approximately 0.5 to 1.5 mm, and the number of blades is approximately For the range of 6 to 9 pieces, the input range is approximately 500 W to 1500 W, and the maximum number of rotations is approximately 35,000 to 50,000 rpm.

Next, the structure in the vicinity of the center portion 300 of the electric blower of the present embodiment will be described using FIG. Fig. 3 is an enlarged view of the vicinity of the center portion 215 of Fig. 2; The seal member 302 corresponding to the seal member 216 of Fig. 2 is fixed by a seal member fixing member 301 attached to the fan case 309 corresponding to the fan case 214 of Fig. 2 . With respect to this sealing material 302, the impeller center portion 315 is invaded to constitute a sealing mechanism. Although this sealing mechanism is important in this position, it is not limited to this. The vane 306 is fixed to the shroud wall 304 on the front side in the axial direction and the hub wall 305 on the rear side in the axial direction by the caulking 317. However, the blade 306 may be fixed by means other than welding or the like. The blade 306 is composed of a flat plate made of a material mainly composed of aluminum having a slightly uniform thickness. Here, the slight uniformity includes thickness due to deformation or thermal deformation during processing, and thickness due to unevenness of the surface. The shield is formed of a flat plate made of a material having a slightly uniform thickness of aluminum as a main component, and has a ring shape. That is, the shield is attached to the opening having a circular shape at the center. The side wall surface of the vane 306 of the shroud is the shroud wall 304. As shown in Fig. 3, the outer edge (outermost circumference in the radial direction) of the shroud faces the radial direction, and the inner edge (the innermost circumference in the radial direction) of the shroud faces the axial direction. As shown in Fig. 3, in the vicinity of the inner edge of the shroud, it gradually changes from the radial direction to the axial direction. The hub is also formed of a flat plate made of a material having a slightly uniform thickness of aluminum as a main component, and has a circular shape or a circular ring shape. The side wall surface of the vane 306 of the hub is the hub wall 305. As shown in Fig. 3, the outer and inner edges of the hub are oriented in the radial direction. Therefore, the outer edge of the shroud and the outer edge of the hub are slightly parallel and separated. The blade 306, the shroud, and the hub may be made of an alloy containing aluminum or a metal other than aluminum (for example, iron, stainless steel, titanium) or ceramic. The riveting is generally performed in plural along both the end surface of the shroud wall 304 on the side surface of the shroud 306 and the end surface of the end surface of the hub wall 305. Here, only the side of the shroud wall 304 and the innermost side (the inner side) are attached. The figure shows. The riveting 317 is preferably formed integrally with the vane 306. For example, when the blade 306 is punched out from the flat plate, the portion of the riveting 317 is also pressed together, and the riveting 317 and the blade 306 can be integrally formed. Alternatively, when the blade 306 is cut out from the flat plate, and the portion of the riveting portion 317 is also cut together, the riveting 317 and the vane 306 may be integrally formed. The side wall surface of the shroud wall 304 of the vane 306 has a shape along the shroud wall 304, and the end surface of the hub wall 305 of the vane 306 has a shape along the hub wall 305. The line of the end surface of the shroud wall 304 of the blade 306 is referred to as a shroud-side curved line, and the line of the end surface of the hub 305 of the vane 306 is referred to as a hub-side curved line. Then, the impeller 303 is constituted by a shroud and a hub and a plurality of blades 306 arranged in the circumferential direction. The hub is fixed to a rotating shaft 308 corresponding to the rotating shaft 205 of FIG. 2, and as a result, the impeller 303 is fixed to the rotating shaft 308. Thereby, the impeller 303 also rotates with the rotation of the rotating shaft 308. The inner edge of the blade 306 protrudes from the front side to form a leading edge 307 of the blade. There is a space between the leading edge 307 of the blade and the rotating shaft 308 to form a flow path. The position of the stationary portion front end 314 of the inner circumference of the fan case 309 does not coincide with the position of the blade leading edge 307 of the blade 306, and the stationary portion front end 314 is located on the front side more than the blade leading edge 307, and has an axial direction step 316. That is, there is a step in the axial direction between the fixed portion and the rotating portion. The position of the stationary portion front end 314 of the inner circumference of the fan case 309 does not coincide with the position of the impeller center portion 315 of the shroud, and the stationary portion front end 314 is located on the inner peripheral side of the impeller center portion 315, and has a radial step difference 310. That is, there is also a step in the radial direction between the fixed portion and the rotating portion. The thick arrow is the direction 313 indicating the airflow. The air enters the entrance of the center portion 215, and flows into a space (flow path) formed between the two adjacent blades 306 in the circumferential direction. Based on the presence of the radial step difference 310, the airflow creates a leak.

Next, the shape of the impeller 400 will be described using FIG. Fig. 4(a) is a front view of the impeller 400 as seen from the front side in the axial direction. The fourth drawing (b) is a side view seen from the side perpendicular to the rotation axis of the impeller 400. As shown in Fig. 4(a), the blades 401 corresponding to the blades 306 of Fig. 3 are provided at eight equal intervals in the outer circumferential direction, and have a rotation direction from the impeller center portion 404 toward the outside in the radial direction. And the direction of reverse rotation, and once again twisted into the shape of the direction of rotation. Further, as shown in Fig. 4(b), the maximum diameter of the shroud wall 402 provided on the front surface of the vane 401 is larger than the maximum diameter of the hub wall 403 provided on the rear side of the vane 401. That is, the outer circumference of the shroud is larger than the outer circumference of the hub. Therefore, the outer edge of the shroud is located on the outer peripheral side of the outer edge of the hub. In addition, the outer edge of the shroud wall 402 and the vane 401 are the same diameter, and the hub wall 403 and the outer edge of the vane 401 are also the same diameter. Therefore, the outer edge of the shroud side of the blade 401 is larger than the outer edge of the hub side.

Next, the shape of the impeller 400 and the diffusion vane 211 will be described using FIG. The diffusion wing 211 is formed to cover the outer peripheral side of the impeller 400. The inner edge of the diffuser 211 of the stationary body is located at the outer edge of the impeller 400 of the rotating body, leaving a position where the impeller 400 can rotate. The blade (stationary blade) 406 in which a plurality of sheets (for example, 13 pieces) of the diffusion vane 211 are formed in the circumferential direction is formed between the annular member on the front side and the annular member on the bottom side. The blade 406 of the diffuser blade 211 is not uniform in thickness and is made of a resin material. Further, the blade 401 with respect to the impeller 400 is twisted to have a three-dimensional shape, and the blade 406 of the diffuser blade 211 is not twisted, but is inclined or curved, and has a two-dimensional shape. The number of blades 406 of the diffuser 214 is more than the number of blades 401 of the impeller 400. The blade 401 of the impeller 400 is inclined or curved in a radial direction centering on the axis of the rotating shaft from the inner edge to the outer edge in a radial direction opposite to the side opposite to the rotational direction 405. On the other hand, the blade 406 of the diffuser blade 211 is inclined or curved in the radial direction about the axis of the rotating shaft from the inner edge to the outer edge in the radial direction about the axis of the rotating shaft. In the case of the blade 401 of the impeller 400, the inclination and the bending direction are opposite to the inclination and the bending direction of the blade 406 of the diffusion wing 211, and the direction of the axial direction of the outer edge (outlet) of the blade 401 of the impeller 400 is The direction in which the axial direction (inlet) of the blade 406 of the diffusion vane 211 is formed is slightly uniform. For example, the direction in which the axial direction of the blade 406 of the diffusion blade 211 is slightly coincident with the axial direction, the direction in which the outer edge of the blade 401 of the impeller 400 is formed is also slightly aligned with the axial direction or only in the rotational direction. A little tilt is better. Thereby, the airflow flowing out from the impeller 400 can flow into the diffusion vane 211 with less turbulence and smoothly.

Next, the shape of the blade 500 will be further described using FIG. Fig. 5 is a front view of one blade 500 as seen from the front side in the axial direction. When viewed in the absolute coordinate space based on the rotation axis direction, the direction from the hub wall of the blade 500 to the direction of the rotation axis of the shroud wall is inclined in the rotation direction 505 near the inlet 503 including the inner edge portion, as The outer edge of the blade is inclined toward the rotation direction, and slightly coincides with the rotation axis direction, and has a slightly two-dimensional shape 506. Further, when the direction from the hub wall of the blade 500 to the direction of rotation of the shroud wall is toward the outer edge of the blade, it is inclined more toward the reverse rotation direction than the direction of the rotation axis, and is inclined toward the maximum inclination in the reverse rotation direction, and further When approaching the outer edge portion, the inclination in the reverse rotation direction becomes small, and the vicinity of the outlet 504 slightly coincides with the direction of the rotation axis, and becomes a slightly two-dimensional shape 507. From the hub wall of the blade 500 to the direction in which the shield wall is formed in the direction of the rotation axis, the outer edge portion is again inclined only slightly (a few degrees) in the direction of rotation. That is, when viewed from the axial direction, the blade 500 is twisted in the reverse rotation direction from the inner edge to the outer edge in a state of being twisted in the rotational direction, and then twisted again in the rotational direction. Then, when viewed from the axial direction, the blade 500 has two slightly two-dimensional shapes 506, 507 from the inner edge to the outer edge, and has a shape in which the oblique direction changes in front and rear. The term "slightly two-dimensional shape" as used herein refers to a plane located in a direction including a rotation axis, and specifically refers to a connection portion of the blade 500 to the shield wall and a connection portion of the blade 500 to the hub wall, which is present in the rotation. In the direction of the axis. The inlet end of the vicinity of the inlet 503 has an inner edge in the radial direction and a leading edge in the circumferential direction (the foremost end of the rotational direction 505). The outlet end of the vicinity of the outlet 504 becomes an outer edge in the radial direction and a trailing edge in the circumferential direction (the last end of the rotational direction 505). That is, in the vicinity of the inlet 503 and the vicinity of the outlet 504, although inclined in the direction of rotation, the inner edge and the outer edge have a slightly two-dimensional shape of two points, and the oblique direction changes in the front and rear of the two-dimensional shape. Further, the blade 500 is formed by bending a flat plate, and its thickness is not particularly thick in the intermediate portion, and is slightly uniform. The inclination of the end surface of the hub side 502 of the intermediate portion of the blade 500 to the end surface of the shield side 501 may be straight or curved (inverted). The direction from the hub wall of the blade 500 to the direction of the rotation axis of the shroud wall may slightly coincide with the direction of the rotation axis in the outer edge portion. The direction in which the direction of the rotation axis of the blade 500 in the inner edge portion is formed is related to the incident angle of the air to the blade 500. The direction in which the direction of the rotation axis of the blade 500 in the outer edge portion is formed is related to the matching of the incident angle of the air of the diffusion fin 211. Therefore, the direction in which the blade 500 in the outer edge portion is formed in the direction of the rotation axis is preferably slightly coincident with the direction in which the blade 406 of the diffusion blade 211 is formed.

The shape of the shroud side 501 is the shape of the hub side 502 on the inner edge side in the radial direction intermediate portion when viewed from the opposite coordinate space based on the shape of the hub side 502 (the hub side curved line). The cover side curved line is curved in the rotational direction, and in the outer edge side among the intermediate portions in the radial direction, the shape of the shield side 501 is curved in the reverse rotation direction with respect to the shape of the hub side 502, in the vicinity of the outlet 504, The shape of the hub side 502 and the shape of the shroud side 501 fly out slightly in the direction of rotation. That is, in the outer edge side of the intermediate portion in the radial direction, the position of the connection portion of the blade 500 to the shroud wall with respect to the inner wall side is located on the side opposite to the rotation direction of the connection portion with the hub wall, and further in the outer edge portion. The connection portion of the blade 500 to the shroud wall is located on the side of the rotation direction with respect to the position of the connection portion with the hub wall, on the outer edge side of the inner peripheral side than the outer edge portion. As a result, from the inner edge to the outer edge of the blade 500, the shape of the hub side 502 (the hub side curved line) and the shape of the shroud side 501 (the shroud side curved line) are intersected at two places.

Next, the specific shape of the blade 601 will be described using FIG. Fig. 6 is a front view of the impeller 600 as seen from the front side in the axial direction, and the blade 601 provided in the plurality of sheets is represented by only one piece. In addition, R1 to 7 in Fig. 6 mean a circle which is concentric with a center portion around the rotation axis, and points and centers at which the respective circles intersect the shape of the shroud side 602 and the shape of the hub side 603. The angle formed by the shaft is taken as the inclination angle θ. The inclination angle θ may also be referred to as an inclination angle of the impeller 600 in the circumferential direction with respect to the axial direction. The inclination angle θ is positive when the shield side shape is inclined toward the rotation direction side, and is negative when it is inclined in the reverse rotation direction. The blade 601 has the same diameter R1 (inner edge portion) as the center portion, and the shape of the shroud side 602 of the blade 601 is inclined by θ1 in the rotational direction 604 as compared with the shape of the hub side 603, toward the outer edge of the blade. In R2, the amount of inclination in the direction of rotation becomes θ2, and in the case of R3 (slightly two-dimensional portion on the inner edge side) toward the outer edge of the blade, the shape of the shroud side 602 and the shape of the hub side 603 intersect. Slightly 2-dimensional shape. Further, in the present invention, θ1 is 11°, θ2 is 9°, and θ1>θ2>θ3 (θ3=0). That is, the blade 601 is the largest inclination in the rotational direction in the inner edge portion. However, the portion having the largest inclination may not be located at the inner edge portion, but may be located slightly on the outer edge side than the inner edge portion. Further, from R3 further toward R4 of the outer edge of the blade, the shape of the shroud side 602 of the blade 601 is inclined by θ4 in the reverse rotation direction and R5 toward the outer edge of the blade as compared with the shape of the hub side 603. In the maximum inclined portion in the rotational direction, the amount of inclination in the reverse rotation direction is θ5, and further toward the outer edge of the blade R6 (slightly two-dimensional portion on the outer edge side), the shape of the shroud side 602 and the hub side 603 The shape crosses again and becomes a slightly 2-dimensional shape. Further, in the present invention, θ4 is -3°, θ5 is -4°, and θ4>θ5>θ6 (θ6=0). Further, the largest inclined portion is formed from the R5 slightly to the inner edge side. Further, from R6 to R7 (outer edge portion) of the outer edge of the blade, the shape of the shroud side 602 of the vane 601 is inclined by θ7 in the rotational direction as compared with the shape of the hub side 603. Further, in the present invention, θ7 is 0.5°. That is, from R1 to R2, the shape of the shroud side 602 is inclined in the direction of rotation as compared with the shape of the hub side 603, and is slightly two-dimensional in R3, and in the reverse rotation direction from R3 to R4, R5. Tilt, in R6, again becomes a slightly two-dimensional shape, and in the outer edge, it is inclined again in the direction of rotation. In other words, when the order is given by a circle on the rotating shaft from the inner edge to the outer edge of the blade, the inclination angle θ with the respective circles is in the order of θ1 > θ2 > θ7 > θ3 = θ6 > θ4 > θ5. The maximum inclination angle of the shroud forming direction of each of the blades of the hub on the concentric circle is preferably 5 to 15 degrees.

The slightly two-dimensional shape of the inner edge side of the two slightly two-dimensional shapes is located on the inner edge side more than the intermediate point in the radial direction. The blade 601 is inclined in the rotation direction on the outer edge side of the innermost side of the innermost side, and the blade 601 is inclined in the reverse rotation direction on the outer edge side of the two-dimensional shape on the inner edge side, but The absolute value of the maximum tilt angle in the direction of rotation (for example, θ1 = 11°) is larger than the absolute value of the maximum tilt angle in the reverse rotation direction (for example, θ5 = -4°). The two-dimensional shape on the outer edge side of the two slightly two-dimensional shapes is located in the vicinity of the outer edge portion (the inner edge side is several mm from the outer edge portion).

Next, the blade angle distribution of the blade of the present invention will be described using Fig. 7. In Fig. 7, an orthogonal line is drawn for a straight line connecting the arbitrary position of the blade to the central axis (the axis of the rotating shaft 308), and the angle formed by the orthogonal line and the outer wiring of the blade is regarded as the blade mounting. Angle or blade angle "β". The horizontal axis is the diameter. As shown in Fig. 7, in the inner edge with the smallest radius, the shroud blade angle is set to be larger than the hub blade angle. More specifically, for the blade shroud diameter D, the shroud inner diameter is 0.387D, and the hub inner diameter is 0.357D, the shroud blade angle is set to about 25 degrees, and the hub blade angle is set to about 22 degrees. That is, in the inner edge, on the hub side, the blade angle on the shroud side is slightly larger, and the inner diameter of the shroud is larger than the inner diameter of the hub. Further, in the outer edge having the largest radius, the shroud blade angle is set to be larger than the hub blade angle, and the shroud-side outer diameter of the outer edge of the blade is set to be larger than the hub side of the outer edge. More specifically, the diameter of the shroud of the outer edge of the blade is taken as D, the diameter of the hub side of the trailing edge is 0.996D, the mounting angle of the shroud blade is set to about 35 degrees, and the mounting angle of the hub vane is set to about 20 degree.

Further, as shown by the solid curve in Fig. 7, as shown by the solid curve in Fig. 7, as the blade edge is increased from the inner edge toward the outer edge of the hub face, the inflection point 702 on the hub side of the inner edge side comes. . Then, the blade angle gradually decreases toward the outer edge and reaches the inflection point 702 on the hub side of the outer edge side. Then, once the inflection point 702 on the hub side of the other edge side is passed, the blade angle decreases again toward the outer edge. That is, the angular distribution of the blades of the succeeding hub is set to have two inflection points 702 on the hub side as they approach the outer edge. In addition, depending on the entry conditions, it may also become a turning point.

Further, the blade angle distribution on the shroud side is as shown by the broken line curve in Fig. 7, with no angle increasing from the inner edge toward the outer edge of the shroud, and the back side of the shroud side on the inner edge side. Point 701 arrives. Then, the blade angle increases toward the outer edge, reaching the inflection point 701 on the shroud side of the outer edge side. Then, as soon as the inflection point 701 on the side of the shroud on the other side is passed, the blade angle of the outer edge is slowly reached toward the outer edge. That is, the angular distribution of the blades of the succeeding hub is set to have two backing points 701 on the shroud side toward the outer edge.

Further, the broken line curve of the blade angular distribution on the shroud side and the solid line curve of the blade angular distribution on the hub side intersect at the outer edge side of the slightly center of the radial direction. From the inner edge side from the intersection 703, the blade angle of the shroud is smaller than the blade angle of the hub, and the blade angle of the shroud is larger than the blade angle of the hub from the intersection. In addition, the maximum angle of the blade angle distribution, the blade angle of the hub is larger with the blade angle of the shield. In addition, the inflection point of the shroud and the hub is located on the more inner side than the intersection 703. The intersection 703 may be closer to the inner edge side than the slightly center position, or may be the outer edge side. The position of the intersection 703 is, for example, related to the flow rate or the angle of incidence of the inflow impeller 303.

Next, Fig. 8 shows a comparison of the efficiency of the design point air volume which is the type of the air blower of the present embodiment described above and the comparative example. Fig. 8 shows a fixed diffusion wing, and the axial power of the blade is set to a constant state. Only the numerical analysis results of the impeller are changed in the comparative example and the present embodiment. As shown in Fig. 8, according to the air blower of the present embodiment described above, it is found that the efficiency of the impeller is small, but it is increased as compared with the comparative example. In addition, the efficiency of the diffusion fins was compared with that of the comparative example, and the efficiency was improved. Further, in the efficiency of the blower including the impeller and the diffusing fin, it was found that the efficiency was improved as compared with the comparative example. According to the blower which is the embodiment, compared with the comparative example, the efficiency of the diffuser is increased more than the efficiency of the impeller, and the efficiency of the diffuser is improved to improve the efficiency of the blower.

Here, Fig. 14 is a view showing the shape of the blade of the present embodiment and the blade of the comparative example. Indicates a single blade that is seen from the front side of the shaft. Fig. 14(a) shows the blade of the present embodiment, and Fig. 14(b) shows the blade of the embodiment. In the comparative example, the position of the shroud-side joint portion in the trailing edge portion of the blade is set to be the reverse rotation direction from the position of the hub-side joint portion, and the hub-side vane outlet angle and the shroud-side vane outlet in the trailing edge portion of the vane are made. The angle becomes equal. That is, from the inner edge to the outer edge of the blade, there is one blade having a slightly two-dimensional shape. The inclination angle of the inner edge portion in the rotation direction of the comparative example coincides with the inclination angle of the inner edge portion in the rotation direction of the present embodiment, and the position of the first two-dimensional shape of the comparative example (the radial position from the axial center) and the present In the two slightly two-dimensional shapes of the embodiment, the positions of the slightly two-dimensional shapes on the inner edge side are the same. The air blower of the air conditioner and the electric air blower are different in size, the number of rotations, and the presence or absence of the diffusion wing. However, for example, the centrifugal fan of the air conditioner of Patent Document 2 is applied to the object of the present embodiment. An example of an electric blower for an electric vacuum cleaner.

In the electric blower of the present embodiment, in order to investigate the impeller efficiency improvement effect of the design point air volume, the comparison of the axial direction distribution of the wind speed in the impeller outlet (at the trailing edge portion) is shown in Fig. 9 (numerical analysis result) . The vertical axis of Fig. 9 indicates the impeller exit speed, and the horizontal axis indicates the axial position from the hub side to the shroud side. In addition, the maximum position on the horizontal axis represents the average speed of the impeller outlet. In the impeller, the smaller the impeller exit velocity, the greater the pressure rise in the impeller and the better the efficiency. In addition, in the electric blower of the electric vacuum cleaner, there is a diffuser wing at the impeller exit, and the distribution of the impeller exit speed is important from the matching with the airflow of the diffuser. From Fig. 9, it is found that the average speed is lowered as compared with the comparative example. Further, when the speed in the axial direction is the same, the difference in speed between the shroud side and the hub side is smaller than in the comparative example. From the above, the velocity distribution inside the impeller is improved, and the efficiency is improved. In the present embodiment, the impeller exit speed increases from the hub side to the central portion in the axial direction, and then increases from the center portion in the axial direction to the shroud side. Further, the impeller exit speed is smaller than the hub end and the shroud end in the central portion in the axial direction. In the present embodiment, in comparison with the comparative example, the impeller exit speed in the central portion in the axial direction from the hub side is small.

Further, Fig. 15 shows a comparison of internal airflow in each cross section of the blade in the axial direction (numerical analysis result). Fig. 15 shows only two of the blades 401 of the eight blades 401 which are present throughout the circumference. The lighter the color, the higher the value and the greater the speed. The velocity distribution shown in Fig. 15 is not the velocity distribution of the absolute coordinates based on the electric blower 106 or the diffuser 211 of the stationary body, but the velocity distribution of the relative coordinates based on the impeller of the rotating body. Therefore, in Fig. 15, the portion having a small speed (the portion having a large color) has a large speed for the diffusion fin 211, and in Fig. 15, the portion having a high speed (the portion having a light color) has a small speed with respect to the diffusion fin 211. The 15th (a), (b) and (c) diagrams show the velocity distribution of the present embodiment, and the 15th (d) and (e) (f) show the velocity distribution of the comparative example. Further, the fifteenth (a) and (d) show the speed distribution of the hub side cross section (the joint portion with the hub wall) in the axial direction, and the fifteenth (c) and (f) show the shroud side cross section of the axial direction. The speed distribution of the joint portion of the cover wall, and fifteenth (b) and (e) show the central cross section in the axial direction (the center between the hub wall and the shroud wall).

When comparing the shroud profiles, the velocity distribution (Fig. 15(c)) of the present embodiment and the velocity distribution of the comparative example (Fig. 15(f)) are not greatly different. It can be considered that both of them have an appropriate angular relationship of the shape of the shield side 501. Even if the central cross section is compared, the velocity distribution (Fig. 15(b)) of the present embodiment and the velocity distribution (Fig. 15(e)) of the comparative example are not greatly different. It can be considered that the angular distribution of the shape of the center in the axial direction is appropriately defined. On the other hand, when comparing the hub section, the velocity distribution (Fig. 15(a)) of the present embodiment is for the velocity distribution of the comparative example (Fig. 15(d)), particularly the reverse rotation direction of the trailing edge portion of the blade. The thick portion is visible on the side, that is, the low velocity region is small (part A in Fig. 15). As shown in Fig. 7, as a result of making the blade angle of the rear edge portion of the hub small, the shape of the rear edge portion of the hub becomes a shape along the air flow, and the low speed region can be lowered. Then, as described in Fig. 9, in comparison with the comparative example, particularly in the case where the low speed region on the hub side is lowered, the speed on the hub side can be reduced, and the average speed can be lowered.

Further, in the electric blower of the present embodiment, in order to investigate the effect of improving the efficiency of the spreader of the design point air volume, Fig. 10 shows a comparison of the internal airflow in the central cross section of the diffuser in the axial direction (the numerical analysis result). Fig. 10 shows that there are 13 blades in the diffusion wing throughout the circumference, and only two blades 1001 are shown. The lighter the color, the higher the value and the greater the speed. That is, when the airflow inside the diffusion vane changes from the pale color to the rich color, the inside of the diffusion vane is decelerated efficiently and the pressure rises. According to Fig. 10, in the comparative example, in the diffusion wing outlet portion 1004, the high speed region 1002 and the low velocity region 1003 exist, and it is known that the airflow from the impeller is not decelerated. That is, it is known that peeling occurs at the diffusion wing outlet portion 1004, and the loss is increased. On the other hand, in the embodiment, the high-speed area or the low-speed area does not exist in the diffuser wing outlet portion 1004, and it is known that the speed is decelerated. That is, the pressure rise inside the diffusion vane in the embodiment, and as compared with the comparative example, the lift is obtained, the energy loss is lowered, and the efficiency is improved. Further, the speed distribution of the hub side cross section and the shroud side cross section of the diffusion vane of the present embodiment is not significantly different from the speed distribution of the hub side cross section and the shroud side cross section of the diffusion vane of the comparative example.

According to the above, in the present embodiment, the shape of the shroud side 501 of the blade, the shape of the central portion in the axial direction, and the shape of the hub side 502 are appropriately adjusted, that is, the inner edge portion to the outer edge portion of each cross section in the axial direction. Appropriate shape can reduce the average speed of the impeller outlet, not only can improve the efficiency of the impeller, especially the efficiency of the diffusion wing. In particular, as a result of reducing the angular distribution of the rear edge portion of the hub side 502, the shape of the shroud side 501 of the blade and the shape of the hub side 502 are not only on the inner edge side but in the vicinity of the outer edge portion as viewed from the direction of the rotation axis. Also cross.

Hereinafter, a method of manufacturing the electric blower of the present invention will be described.

The riveting will be described using Fig. 11. A plurality of caulking projections 1105 (rivets) are provided in each of the upper end portion (the front side in the axial direction) and the lower end portion on the hub side (the rear side in the axial direction) of the vane 1104 corresponding to the vane 306 of FIG. 3 . As described above, the staking protrusion 1105 is preferably formed integrally with the blade 1104. In order to match the position and number of the caulking protrusions 1105 of the blade, a plurality of caulking holes 1102 are provided in the shroud wall 1103 and the hub wall 1101. Therefore, the relative position between the plurality of caulking holes 1102 of the shroud wall 1103 is a position along the shape of the upper end portion of the blade 1104, and the relative position between the plurality of caulking holes 1102 of the hub wall 1101 is along the blade. The position of the shape of the lower end of 1104. The caulking hole 1102 is a through hole. For example, in the case where all are slightly two-dimensional, the relative positions between the plurality of caulking holes 1102 of the shroud wall 1103 and the relative positions of the plurality of caulking holes 1102 of the hub wall 1101 are almost the same, in this embodiment, In the inner edge side of the blade, the upper end portion of the blade 1104 of the blade 1104 is more inclined than the lower end portion toward the front side in the rotational direction 405, and therefore, the relative position between the plurality of caulking holes 1102 of the shield wall 1103, and the plural of the hub 801 The relative position between the caulking holes 1102 is a position that expands toward the front side in the rotational direction 405. In Fig. 11, the shroud and the hub side have three riveting structures. The respective positions of the caulking projections 1105 at the upper end portions of the vanes 1104 correspond to the respective positions of the caulking projections 1105 at the lower end portions of the vanes 1104. The caulking protrusion 1105 of the blade 1104 is inserted into the shroud wall 1103 and the caulking hole 1102 of the hub wall 1101, and the blade 1104 is integrally assembled with the shroud wall 1103 and the hub wall 1101 by riveting from the outside. Further, the blade shape shown in Fig. 11 is a flat blade shape in which the blade outer diameter D2: 89 mm, the blade width b2: 6.8 mm, and b2/D2 = about 0.08. Here, the caulking means that the caulking projection 1105 is inserted into the caulking hole 1102, and the caulking hole 1102 is inserted, and the tip end of the caulking projection 1105 flying out of the opposite side is crushed by a special tool or a dedicated device. The caulking hole 1102 of the hub wall 1101 is inserted into the riveting projection 1105 of the blade 1104, and the blade 1104 is fixed to the hub wall 1101, and then inserted into the caulking hole 1102 of the shroud wall 1103 into the riveting projection 1105 of the blade 1104. Riveting is also possible, and vice versa. In addition, the caulking hole 1102 of the hub wall 1101 and the caulking hole 1102 of the shroud wall 1103 are inserted into the caulking protrusion 1105 of the blade 1104, and then riveted.

Compared with the comparative example, in the present embodiment, in the blade 1200, particularly in the inner edge side, by tilting the blade 1200 toward the front side in the rotational direction, the blade 1200 and the shroud wall 304 and the blade 1200 and the hub are maintained. Airtightness between the walls 305 becomes difficult. Therefore, it is preferable to cover the caulking portion (connection portion) of the blade 1200 and the shroud wall 304 and the caulking portion (connection portion) of the blade 1200 and the hub wall 305 by electrocoating or an adhesive. In particular, it is preferable that the adhesion is lower than the electrocoating or the adhesive used in the comparative example. Thereby, it is possible to prevent a gap between the blade portion 1200 and the caulking portion (connection portion) of the shroud wall 304 and the caulking portion (connection portion) of the blade 1200 and the hub wall 305, thereby suppressing disturbance of the air flow, and suppressing reduction in efficiency. .

[Embodiment 2]

The same components as those in the first embodiment are given the same reference numerals, and the description thereof will be omitted.

In the manufacturing method of the riveting described above, when the blade is inclined in the rotational direction, the blade is easily slid in the rotational direction due to the difference in the position of the shield in the rotational direction of the hub, and the assembly accuracy is lowered. Question.

On the other hand, as shown in FIG. 12, in the second embodiment, as described above, the shroud forming direction of each of the blades of the hub is inclined in the rotational direction in the inner edge of the blade, as The inner edge and the outer edge of the blade are inclined in the reverse rotation direction, and have a slightly two-dimensional shape with the hub side, and then become the reverse rotation direction, and become slightly two-dimensional shape from the outer edge of the blade, and the blade is The outer edge is again inclined in the direction of rotation, and has a blade having a two-dimensional shape of two points from the inner edge to the outer edge of the blade. Therefore, as shown in Fig. 12, the caulking projection 1205 is used for the shroud side 1201 and the hub side 1202 in a two-dimensional shape at two points, so that the blade can be prevented from slipping during the caulking, and the shroud side can be removed. The distance b between the 1201 and the hub side 1202 is controlled to be manufactured in a specific size. Further, in the inner edge side and the outer edge side of the two-dimensional shape of the two points, the inclination direction of the blade is changed, and the effect of the stress at the time of the caulking is also canceled. Further, in order to obtain an effect, the protrusion for riveting may be provided in a slightly two-dimensional shape.

Compared with the comparative example, in the present embodiment, in the special inner edge side of the blade 1200, the blade 1200 and the shroud wall 304 and the blade 1200 and the hub wall 305 are maintained by tilting the blade 1200 toward the front side in the rotational direction. The airtightness between them becomes difficult. Therefore, it is preferable to cover the caulking portion (connection portion) of the blade 1200 and the shroud wall 304 and the caulking portion (connection portion) of the blade 1200 and the hub wall 305 by electrocoating or an adhesive. In particular, it is preferable that the adhesion is lower than the electrocoating or the adhesive used in the comparative example. Thereby, it is possible to prevent a gap between the blade portion 1200 and the caulking portion (connection portion) of the shroud wall 304 and the caulking portion (connection portion) of the blade 1200 and the hub wall 305, thereby suppressing disturbance of the air flow, and suppressing reduction in efficiency. .

100. . . Electric vacuum cleaner body

101. . . Hose connector

102. . . Dust chamber

103. . . Paper bag

104. . . Filter section

105. . . Motor room

106. . . Electric blower

107. . . Anti-vibration rubber

108. . . Blower inlet

109. . . Blower outlet

110. . . Power cord reel

111. . . wheel

201. . . Blower

202. . . electric motor

203. . . cabinet

204. . . Rear end cover

205, 308. . . Rotary axis

206. . . Rotor

207. . . stator

208. . . Carbon brush

209. . . Rectifier

210, 303, 400, 600. . . impeller

211. . . Diffusion wing

212. . . Compartment board

213. . . Return guide

214, 309. . . Fan shell

215, 300. . . Central department

216, 302. . . Sealing material

217. . . Electric blower inlet

301. . . Sealing material fixing member

304, 402, 1103. . . Shield wall

305, 403, 1101. . . Hub wall

306, 401, 601, 1104, 1200. . . blade

307. . . Blade leading edge

310. . . Radial step difference

313. . . Direction of air flow

314. . . Stationary front

315, 404. . . Impeller center

316. . . Axis direction difference

317. . . Riveting

405, 505, 604, 1203. . . turn around

501, 602, 1201. . . Shield side

502, 603, 1202. . . Hub side

503. . . Near the entrance

504. . . Near the exit

506, 507. . . Slightly 2-dimensional shape

701. . . Folding point on the side of the shield

702. . . The turning point on the hub side

703. . . intersection

1001. . . blade

1002. . . High speed area

1003. . . Low speed zone

1004. . . Diffusion wing outlet

1102. . . Riveting hole

1105, 1205. . . Riveting protrusion

Figure 1 is a cross-sectional view of the model of the vacuum cleaner body.

Fig. 2 is a cross-sectional view showing an electric blower for a vacuum cleaner.

Fig. 3 is a structural view of the vicinity of the center portion of the impeller.

Figure 4 is a diagram of the shape of the impeller.

Figure 5 is a diagram of the shape of the thin blade.

Figure 6 shows the detailed shape of the blade.

Figure 7 is a diagram showing the blade mounting angle distribution of the shield of the blade and the contact surface of the main plate.

Fig. 8 is a comparison diagram of the efficiencies of the examples and comparative examples.

Fig. 9 is a comparison diagram of the axial direction distribution of the impeller exit speeds of the examples and the comparative examples.

Fig. 10 is a comparison diagram showing the velocity distribution of the central section in the axial direction of the inside of the diffusion vane of the embodiment and the comparative example.

Figure 11 is a view showing the position of the riveting.

Fig. 12 is a view showing a projection of the riveting.

Figure 13 is a diagram showing the shape of the impeller and the diffuser.

Fig. 14 is a view showing the shape of the blades of the present embodiment and the comparative example.

Fig. 15 is a comparison diagram showing the velocity distributions of the respective sections in the axial direction of the impeller inside the embodiment and the comparative example.

500. . . blade

501. . . Shield side

502. . . Hub side

503. . . Near the entrance

504. . . Near the exit

505. . . turn around

506, 507. . . Slightly 2-dimensional shape

Claims (8)

An electric blower includes: a ring-shaped shroud; and a hub disposed to face the shroud; and a plurality of blades disposed between the shroud and the hub in a circumferential direction; and rotating the shroud and the aforesaid The electric motor of the hub and the blade is characterized in that each of the blades is formed by a flat plate, and each of the blades is rotated from the inner edge in the radial direction toward the outer edge in the radial direction with respect to the direction of the rotation axis. The state in which the direction side is twisted is twisted toward the reverse rotation axis direction side, and then twisted again toward the rotation direction side. An electric blower includes: a ring-shaped shroud; and a hub disposed to face the shroud; and a plurality of blades disposed between the shroud and the hub in a circumferential direction; and rotating the shroud and the aforesaid The electric motor of the hub and the blade, wherein the electric blower is characterized in that each of the blades is formed by a flat plate, and each of the blades is formed from a connection portion with the hub toward a rotation axis direction of a connection portion with the shroud. The direction of the outer edge portion of the blade in the radial direction slightly coincides with the direction of the rotation axis, or is inclined toward the rotation direction side with respect to the rotation axis direction, and each of the blades has a direction in which the rotation axis direction is formed. The intermediate portion in the radial direction of the blade is a portion inclined toward the rotation direction side with respect to the rotation axis direction and a portion inclined toward the reverse rotation direction side with respect to the rotation axis direction. An electric blower includes: a ring-shaped shroud; and a hub disposed facing the shroud; and a plurality of the plurality of guards disposed in the circumferential direction a vane between the cover and the hub, and an electric motor that rotates the shroud and the hub and the blade. The electric blower is characterized in that each blade is formed by a flat plate, and viewed from a direction of a rotating shaft, the blade The arc-shaped line on the hub side of the connecting portion with the hub and the shroud-side curved line in the connecting portion of the blade and the shroud intersect at least at two points from the inner edge in the radial direction to the outer edge in the radial direction. The electric blower according to claim 1, wherein each of the blades is an orthogonal line connecting a straight line between an arbitrary position of the connecting blade and the axis of the rotating shaft, and is curved from the direction of the rotating shaft. When the angle formed by the wiring outside the blade is defined as the blade angle, the blade angle of the hub side of the blade is larger than the blade angle of the shroud side of the blade in the radially inner edge portion and the radial outer edge portion. small. An electric vacuum cleaner includes: an electric blower that generates an attractive force; a dust collecting chamber that communicates with the electric blower; and a suction member that communicates with the dust collecting chamber. The electric vacuum cleaner is characterized in that the electric blower includes: a ring-shaped shroud, a hub facing the shroud, a blade disposed between the shroud and the hub in a circumferential direction, and a rotating portion that rotates the shroud and the hub and the blade Each of the blades is formed by a flat plate, and each of the blades is radially outward from the inner edge of the radial direction to The rotation axis direction is a reference, and the state of being twisted toward the rotation direction side is twisted toward the reverse rotation axis direction side, and then twisted again toward the rotation direction side. An electric vacuum cleaner includes: an electric blower that generates an attractive force; a dust collecting chamber that communicates with the electric blower; and a suction member that communicates with the dust collecting chamber. The electric vacuum cleaner is characterized in that the electric blower includes: a ring-shaped shroud, a hub facing the shroud, a blade disposed between the shroud and the hub in a circumferential direction, and a rotating portion that rotates the shroud and the hub and the blade Each blade is formed by a flat plate, and viewed from the direction of the rotation axis, the arc side of the hub side in the connection portion between the blade and the hub, and the shield side curved portion in the connection portion of the blade and the shroud The line intersects at least at two points from the inner edge in the radial direction to the outer edge in the radial direction. The electric blower according to any one of claims 1 to 4, further comprising: a blower having a diffuser formed to cover an outer peripheral side of the vane, wherein an outer edge of the vane is axially oriented The forming direction is substantially the same as the direction in which the axial direction of the inner edge of the blade of the diffusing member is formed. The electric vacuum cleaner according to claim 5, further comprising a blower having a diffuser formed to cover an outer peripheral side of the vane, wherein an axial direction of the outer edge of the vane is formed in a direction The direction in which the axial direction of the inner edge of the blade of the diffuser is substantially the same.