WO2021106317A1

WO2021106317A1 - Blower and washing machine

Info

Publication number: WO2021106317A1
Application number: PCT/JP2020/034439
Authority: WO
Inventors: 和寛塚本; 武史本多; 聡凜佐々木; 川村　圭三; 二郎藁谷; 道太菅原
Original assignee: 日立グローバルライフソリューションズ株式会社
Priority date: 2019-11-27
Filing date: 2020-09-11
Publication date: 2021-06-03
Also published as: JP2021085347A; JP7452989B2; CN114729648A

Abstract

The present invention comprises: an electric motor; a rotating shaft rotatably provided to the electric motor; a centrifugal impeller (300) provided to the rotating shaft; a diffuser flow path (410) that is provided downstream of the centrifugal impeller (300) and that is constituted by a vane arranged in a circumferential direction; and a scroll flow path (70) that is provided downstream of the diffuser flow path (410) and on the side opposite the axial direction with respect to the diffuser flow path (410). With reference to a tongue end (71) of the scroll flow path (70), the length of a diffuser vane (401) changes toward the direction of rotation (W) of the centrifugal impeller (300).

Description

Blower and washing machine

The present invention relates to a blower and a washing machine equipped with the blower.

The blower rotates the impeller with an electric motor to create an air flow. The air flowing in from the suction port of the blower is boosted and accelerated by the impeller, and decelerated in the stationary flow path, so that the kinetic energy of the inflowing air is converted into pressure energy and the pressure rises. In order to obtain a highly efficient blower, a static flow path that performs good pressure recovery is important. As a blower having a stationary flow path, there is one described in Patent Document 1. Patent Document 1 describes a blower having a configuration in which the rotating shaft of the impeller and the central shaft of the diffuser are different from each other.

Japanese Unexamined Patent Publication No. 2014-202102

The blower described in Patent Document 1 has blades on the central axis of the diffuser in order to suppress a decrease in pressure recovery rate, that is, a decrease in efficiency due to a pressure distribution generated in the circumferential direction in the diffuser due to the influence of a scroll provided downstream of the diffuser. It is characterized by shifting with respect to the rotation axis of the car. As a result, the pressure recovery rate by the diffuser is changed in the circumferential direction and offset by the pressure distribution caused by scrolling, so that the pressure distribution in the circumferential direction is made uniform and high efficiency is realized.

However, in the blower described in Patent Document 1, the maximum pressure recovery rate by the diffuser is almost determined by the length of the diffuser vane which is uniform in the circumferential direction. In this case, if the blower is miniaturized, the length of the diffuser vane is also shortened evenly in the circumferential direction, and the pressure recovery rate is lowered. Therefore, it has been difficult to achieve both miniaturization and high efficiency.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a blower capable of achieving both miniaturization and high efficiency, and a washing machine equipped with the blower.

The present invention is a diffuser composed of an electric motor, a rotating shaft rotatably provided on the electric motor, an impeller provided on the rotating shaft, and vanes provided downstream of the impeller and arranged in the circumferential direction. A flow path and a scroll flow path provided downstream of the diffuser flow path on the side opposite to the axial direction of the rotation axis with respect to the diffuser flow path are provided, and the tongue portion of the scroll flow path is used as a reference. , The vane length changes as the impeller rotates in the direction of rotation.

According to the present invention, it is possible to provide a blower capable of achieving both miniaturization and high efficiency, and a washing machine equipped with the blower.

It is a vertical sectional view which shows the washing machine which mounted the blower of 1st Embodiment. It is an external perspective view which shows the blower of 1st Embodiment. It is an exploded perspective view of the blower when viewed from the fan cover side. It is an exploded perspective view of the blower when viewed from the motor side. It is a top view of the conventional diffuser. It is a top view of the blower equipped with the conventional diffuser. It is a schematic diagram which shows the communication passage formed by the conventional diffuser. It is a top view of the diffuser of 1st Embodiment. It is a top view of the blower equipped with the diffuser of 1st Embodiment. It is a schematic diagram which shows the communication passage formed by the diffuser of 1st Embodiment. It is a perspective view of the blower equipped with the diffuser of 2nd Embodiment.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 is a vertical cross-sectional view showing a washing machine equipped with the blower of the present embodiment. In the following, a vertical washer / dryer will be described as an example, but it can also be applied to a drum-type washer / dryer having a laundry inlet / outlet port formed on the front side.

As shown in FIG. 1, the washing machine S includes an outer frame 1 which is a housing, an outer tub 2 for storing washing water, a rotary tub 3, a drive motor 10, a blower 22 and the like. The outer tub 2 is built in the outer frame 1 and is vibration-proof supported by the outer frame 1. The rotary tub 3 is a washing / dehydrating tub for accommodating laundry such as clothes to be washed and dried, and is provided inside the outer tub 2. Further, the rotary tank 3 is rotatably supported in the outer tank 2.

At the bottom of the rotary tub 3, a stirring blade 4 for stirring and washing the laundry is rotatably provided. The stirring blade 4 repeats forward / reverse rotation during washing operation and drying operation. Further, the stirring blade 4 rotates at high speed together with the rotary tub 3 during the dehydration operation to dehydrate the water contained in the laundry in the rotary tub 3.

The drive motor 10 is provided in the outer frame 1 and drives the stirring blade 4 and the rotary tank 3 in rotation. Further, as the drive motor 10, for example, a DC brushless motor is used. The DC brushless motor is controlled by a vector. In the present embodiment, the stirring blade 4 and the rotary tank 3 are directly rotationally driven by the drive motor 10, but may be driven by using a belt or the like (not shown).

Further, an outer lid 5 is provided on the upper part of the outer frame 1. The outer lid 5 is provided on a top cover 6 provided on the upper part of the outer frame 1 so as to be openable and closable. An inner lid 34 is provided on the upper portion of the outer tank 2 so as to be openable and closable. By opening the outer lid 5 and the inner lid 34, laundry can be taken in and out of the rotary tub 3.

Further, in the outer frame 1, a water supply unit 7 is provided on the back side of the top cover 6. The water supply unit 7 has a water supply box (not shown) having a plurality of water channels inside, and supplies tap water or bath water from the water supply hose connection port 8 to the outer tank 2. Further, on the front side of the top cover 6, a detergent and finishing agent charging device 35 is provided. The detergent and finishing agent are poured between the outer tank 2 and the rotary tank 3 by the charging hose 36.

Further, the washing machine S is provided with a drying mechanism 9. The drying mechanism 9 circulates and dehumidifies the drying air for drying the laundry in the rotary tub 3. Further, the drying mechanism 9 is mostly occupied by the air circulation path for drying. The drying air circulation passage includes a bottom circulation passage 20 connected so as to communicate with the bottom of the outer tank 2, and a dehumidifying vertical passage 21 extending upward from the bottom circulation passage 20.

The suction side of the blower 22 is connected to the upper side of the dehumidifying vertical passage 21. The discharge side of the blower 22 is connected so as to communicate with the return connection circulation path 25. Further, a drying filter 45 is arranged between the blower 22 and the dehumidifying vertical passage 21 to prevent foreign matter from flowing into the blower 22. The details of the blower 22 will be described later.

The return connection circulation path 25 has an upper bellows hose 23, and is connected so as to communicate with the upper part of the outer tank 2 via the upper bellows hose 23. The bottom circulation path 20 also has a lower bellows hose 26, and is connected to the bottom of the outer tank 2 via the lower bellows hose 26.

The lower bellows hose 26 is connected to the bottom drop portion 31 of the outer tank 2. The bottom drop portion 31 communicates with the washing water drainage channel 42 and the washing water circulation water channel 43 via the lower communication pipe 41. A drain valve 44 is provided in the washing water drainage channel 42. A foreign matter removing trap 32 is provided in the washing water circulation water channel 43.

The drain valve 44 is closed during the washing operation and the drying operation. Further, the drain valve 44 is opened at the time of draining the washing water, and the washing water and rinsing water accumulated in the outer tub 2 are discharged from the washing water drainage channel 42 to the outside (outside the machine) of the washing machine S.

The washing water circulation water channel 43 is connected to the washing water circulation water vertical water channel 46. The washing water circulating water vertical channel 46 rises along the outer surface of the outer tub 2 and extends to the upper side of the rotary tub 3 so as to communicate with the washing thread waste removing device 33 provided on the upper side of the rotary tub 3. Be connected.

The washing water and rinsing water collected in the outer tub 2 flows through the washing water circulating water vertical water channel 46 and is poured from the washing thread waste removing device 33 into the rotary tub 3. Since washing and rinsing are performed while this spraying and water injection continues, washing and rinsing are performed with a small amount of water.

Further, the washing machine S is provided with a water level sensor 47 that detects the water level of washing water and rinsing water accumulated in the outer tub 2. An air trap 50 is provided near the bottom of the outer tank 2. An air tube 49 is connected so as to communicate with the air trap 50. A water level sensor 47 is connected to the upper end of the air tube 49 so as to communicate with the upper end. The water level sensor 47 detects the fluctuation of the water level in the outer tank 2 to detect the water level.

Further, in the washing machine S, the centrifugal impeller 300 (see FIG. 2) of the blower 22 rotates, so that the drying air circulates in the rotary tub 3 and dries the laundry in the rotary tub 3. Further, the electric heater 24 (see FIG. 3) of the blower 22 reheats the drying air in which the moisture is condensed in the dehumidifying region and flows through the rotary tub 3, so that the moisture in the laundry is further evaporated. The laundry is dried by repeating this water removal in the circulation of the drying air.

FIG. 2 is an external perspective view showing the blower of the first embodiment.
As shown in FIG. 2, the blower 22 includes a fan cover 51, a fan casing 52, an electric motor 100, a centrifugal impeller 300, a diffuser 400 (see FIG. 3), and an electric heater 24 (see FIG. 3). .. When the blower 22 is mounted on the washing machine S (see FIG. 1), for example, the fan cover 51 of the blower 22 is installed in the outer frame 1 (see FIG. 1) so as to be substantially downward.

The fan cover 51 is formed with a suction port 57 and an discharge port 58. The suction port 57 is connected to the dehumidifying vertical passage 21 (see FIG. 1) via the drying filter 45 (see FIG. 1). The discharge port 58 is connected to the return connection circulation path 25 (see FIG. 1) of the drying air circulation path.

FIG. 3 is an exploded perspective view of the blower when viewed from the fan cover side.
As shown in FIG. 3, the fan cover 51 has an elongated shape in one direction, a suction port 57 is formed on one side in the longitudinal direction, and a discharge port 58 is formed on the other side in the longitudinal direction. The suction port 57 is a circular through hole and faces the center of the suction opening 302 of the centrifugal impeller 300. The discharge port 58 is a circular through hole and is located on the downstream side of the electric heater 24. Further, the diameter of the discharge port 58 is formed to be larger than the diameter of the suction port 57. Further, the suction port 57 and the discharge port 58 are formed so as to face substantially the same direction.

Further, the fan cover 51 is formed with an annular protrusion 51a protruding in the axial direction Ax around the suction port 57. The axial direction Ax means the direction in which the rotating shaft 101 of the electric motor 100 extends. Further, the fan cover 51 has a substantially rectangular protrusion 51b formed at a position where the electric heater 24 is provided.

Further, on the peripheral edge of the fan cover 51, screw fixing portions 91 to be screw-fixed to the fan casing 52 are formed at a plurality of places.

The fan casing 52 has a shape corresponding to the fan cover 51. When the fan casing 52 and the fan cover 51 are combined, a space for arranging the centrifugal impeller 300, the diffuser 400, and the electric heater 24 is formed between the fan cover 51 and the fan casing 52. ing.

Further, in the fan casing 52, a scroll flow path 70 is formed on the back surface (lower surface) side on which the diffuser 400 is arranged. The scroll flow path 70 is formed so that the flow path width on the tongue end portion 71 side is narrow and the flow path width gradually increases in the clockwise direction from the tongue end portion 71. The tip of the tongue 71 is the starting point of the scroll flow path 70. The outlet of the scroll flow path 70 is the casing discharge port 59 (see the shaded area).

Further, the fan casing 52 is formed with an introduction path 72a for introducing air from the scroll flow path 70 into the electric heater 24. The electric heater 24 includes a large number of fins, flows out of the scroll flow path 70, and heats the air that has passed through the introduction path 72a. The introduction path 72a is configured so that the flow path width widens toward the electric heater 24. More specifically, the introduction path 72a is configured to extend to substantially the same width as the width of the heating portion 24a of the electric heater 24. Further, the introduction path 72b (see FIG. 4) of the fan cover 51 is also configured so that the flow path width widens toward the downstream as in the introduction path 72a. By combining the fan casing 52 and the fan cover 51, an introduction path 72 (see FIG. 2) having a shape along the rectangular heating portion 24a of the electric heater 24 is formed.

Further, in the fan casing 52, a concave flow path 77 communicating with the discharge port 58 of the fan cover 51 is formed on the downstream side of the electric heater 24. Further, the flow path 77 is configured to be obliquely upward so as to be inclined toward the discharge port 58.

Further, the fan casing 52 has a shape that protrudes in the width direction so that the position deviated from the heating portion of the electric heater 24 does not interfere with the air flow.

Further, in the fan casing 52, a shaft insertion hole 80 into which the rotation shaft 101 of the electric motor 100 is inserted is formed in the center of the scroll flow path 70. Further, on the outer peripheral edge portion of the fan casing 52, a screw insertion portion 92 through which a screw (not shown) is inserted is formed at a position corresponding to the screw fixing portion 91 of the fan cover 51.

Further, in the fan casing 52, screw holes 93 for fixing the diffuser 400 to the fan casing 52 are formed at a plurality of locations (4 locations in the present embodiment) between the shaft insertion hole 80 and the scroll flow path 70. ing. These screw holes 93 are formed so as to surround the shaft insertion hole 80. Further, the fan casing 52 has a circular recess 93a formed on the peripheral edge of the screw hole 93.

Further, in the fan casing 52, a fan casing recess 94 (concave groove portion) is formed on the radial outer peripheral side of the screw hole 93. The fan casing recess 94 is formed in an annular shape.

The motor 100 has a rotating shaft 101 coupled to the centrifugal impeller 300 at the center in the radial direction, and is attached to the fan casing 52. Further, the motor 100 has a rotor (rotor) fixed to the rotating shaft 101, a stator (stator) provided around the rotor, and a bearing that rotatably supports the rotating shaft 101. Further, the motor 100 has a substantially columnar case 102 that houses a rotor, a stator, and a bearing. An annular brim 103 is formed on the outer peripheral surface (side surface) of the case 102. In the brim 103, screw insertion holes 104 for screw-fixing the motor 100 to the fan casing 52 are formed at a plurality of locations (four locations in the present embodiment) at intervals in the circumferential direction.

The diffuser 400 is formed of, for example, a synthetic resin, and has a circular bottom plate 400a facing the surface of the centrifugal impeller 300 in the axial direction Ax. The bottom plate 400a has a circular through hole 400b formed in the center in the radial direction. The through hole 400b is formed to have a diameter larger than that of the shaft insertion hole 80 of the fan casing 52. Further, the bottom plate 400a is formed with a plurality of screw insertion holes 430 around the through holes 400b through which screws (not shown) for fixing the diffuser 400 to the fan casing 52 are inserted. The screw insertion hole 430 is formed at a position corresponding to (opposing) the screw hole 93 of the fan casing 52.

Further, in the diffuser 400, a recessed portion 430a is formed on the peripheral edge of the screw insertion hole 430 so that the head of the screw (not shown) does not protrude from the surface (upper surface of the drawing) of the bottom plate 400a. As a result, when the centrifugal impeller 300 rotates, the distance between the bottom plate 400a and the centrifugal impeller 300 is shortened, and the centrifugal impeller 300 does not come into contact with the screw (not shown).

A diffuser outer bottom surface (base) 400c formed one step higher in the axial direction Ax than the bottom plate 400a is formed on the entire outer peripheral edge of the bottom plate 400a. Diffuser vanes 401 (vanes) are formed at equal intervals along the circumferential direction on the upper surface (the surface on the fan cover 51 side) of the outer bottom surface portion 400c of the diffuser in the axial direction.

FIG. 4 is an exploded perspective view of the blower when viewed from the motor side.
As shown in FIG. 4, a bell mouth portion 57a is formed at the suction port 57 of the fan cover 51. Further, the fan cover 51 is formed with a recess 51c in which a ring-shaped sealing member (not shown) is housed around the bell mouth portion 57a. Further, the fan cover 51 is provided with an annular holding member (not shown) for holding the seal member (not shown) in the recess 51c. This holding member (not shown) is placed in an annular recess 51d formed around the recess 51c and formed one step higher (shallow) than the recess 51c. Further, the holding member (not shown) is fixed via a fixing portion 51e formed around the recess 51d.

Further, the fan cover 51 is provided with an elastic member 90 formed in an annular shape. Note that FIG. 4 illustrates a state in which the elastic member 90 is attached to the fan cover 51. The elastic member 90 is arranged at a position facing the tip (upper end) of the diffuser vane 401.

Further, the fan cover 51 is formed with an introduction path 72b extending from the scroll flow path 70 (see FIG. 3) toward the electric heater 24. The introduction path 72b is formed along the introduction path 72a (see FIG. 3). Further, the introduction path 72b is configured so that the depth dimension H (flow path height) of the flow path becomes deeper (higher) from the scroll flow path 70 (see FIG. 3) side toward the electric heater 24.

The scroll flow path 70 of the fan casing 52 is configured to bulge toward the side where the motor 100 is installed (motor installation side). Further, in the scroll flow path 70, the flow path depth (depth of Ax in the axial direction) gradually increases from the flow path on the tongue end 71 (see FIG. 3) side toward the introduction path 72a (see FIG. 3). It is configured to be deep in. Further, the introduction path 72a is configured so that the flow path depth becomes substantially constant toward the electric heater 24. The flow path 77 on the downstream side of the electric heater 24 is configured to be lifted toward the fan cover 51 side.

Further, the fan casing 52 is formed with screw bosses 78 for fixing the motor 100 to the fan casing 52 at a plurality of locations (four locations in the present embodiment).

The diffuser 400 has a ridge portion 440 formed on the side (rear side) opposite to the surface on which the diffuser vane 401 is provided. The ridge portion 440 fits into the fan casing recess 94 (see FIG. 3) of the fan casing 52.

Further, the screw insertion hole 430 of the diffuser 400 is formed with a protrusion 430b that is unevenly fitted with the recess 93a (see FIG. 3) of the fan casing 52. Each protrusion 430b fits into a recess 93a corresponding to each of the fan casings 52.

Further, the screw insertion hole 430 of the diffuser 400 and the screw hole 93 of the fan casing 52 are fixed by screws (not shown). The rotating shaft 101 (see FIG. 3) of the electric motor 100 is inserted into the shaft insertion hole 80 of the fan casing 52. Then, the rotary shaft 101 is inserted into the through hole 400b of the diffuser 400, and the tip of the rotary shaft 101 is coupled (fixed) to the centrifugal impeller 300.

The fan cover 51 and the fan casing 52 are connected to each other by inserting a screw (not shown) into the screw insertion portion 92 and fixing the screw (not shown) to the screw fixing portion 91. As a result, the blower 22 forms a casing portion 61 (see FIG. 2) in which the centrifugal impeller 300 and the diffuser 400 are arranged, and a heater portion 62 (see FIG. 2) in which the electric heater 24 is arranged. The connection space boundary surface between the casing portion 61 and the heater portion 62 is designated as the casing discharge port 59 (see FIG. 3).

Further, in the centrifugal impeller 300, the inner diameter end of the blade 321 is located radially outside the suction opening 302 (see FIG. 3). Further, the centrifugal impeller 300 is configured such that the outer diameter end portion of the blade 321 substantially coincides with the outer peripheral edge portion of the shroud plate 301 and the outer peripheral edge portion of the hub plate 311.

In the first embodiment, a closed type centrifugal impeller 300 having a shroud plate 301 will be described as an example, but an open type centrifugal impeller in which the hub plate 311 and the blade 321 are integrally molded with resin may be used. .. As a result, the number of parts can be reduced and the cost can be reduced. In addition, the resin type facilitates three-dimensionalization and improves efficiency. The three-dimensionalization is to form the blade by further twisting it. As a result, efficiency can be further improved.

Further, in the first embodiment, a turbofan having rearward blades will be described as an example, but a sirocco fan having forward blades may be applied. Further, the shape of the impeller is not limited to the centrifugal type, and may be a mixed flow type. By adopting the oblique flow type, the outer diameter of the impeller can be miniaturized, and the blower 22 can be miniaturized.

Next, a blower equipped with a diffuser as a conventional example will be described. FIG. 5 is a plan view of a conventional diffuser. FIG. 6 is a plan view of a blower equipped with a conventional diffuser. FIG. 7 is a schematic view showing a communication passage formed by a conventional diffuser.
As shown in FIG. 5, the diffuser 1400 is configured such that a plurality of diffuser vanes 1401 are arranged around the bottom plate 1400a at equal intervals in the entire circumferential direction. The diffuser vane 1401 is formed so as to stand up in the axial direction Ax (see FIGS. 3 and 4) with respect to the diffuser outer bottom surface portion 1400c formed around the bottom plate 1400a. Further, the diffuser vane 1401 is located outside the outer peripheral edge portion of the centrifugal impeller 300 (see FIGS. 3 and 4).

The diffuser vane 1401 is formed in a thin plate shape and extends in the circumferential direction in a plan view. Further, the diffuser vane 1401 is configured such that the trailing edge 1402 (the other end) is located radially outside the front edge 1412 (one end). Further, in the diffuser vane 1401A (1401), the front edge 1412 of the diffuser vane 1401B (1401) adjacent to the diffuser vane 1401B (1401) is located substantially in the center in the circumferential direction and inside the radial direction of the diffuser vane 1401A. In other words, in the diffuser vane 1401B (1401), the trailing edge 1402 of the diffuser vane 1401A (1401) adjacent to the diffuser vane 1401B (1401) is located substantially in the center in the circumferential direction and outside in the radial direction of the diffuser vane 1401B. Further, a diffuser flow path 1410 described later is formed between the

adjacent diffuser vanes

1401A and 1401B. The diffuser flow path 1410 is configured so that the width in the radial direction gradually increases from the front edge 1412 side to the trailing edge 1402 side.

Further, in the diffuser vane 1401A (1401), the cut portion 1404 is provided so that the outer peripheral edge portion of the diffuser outer bottom surface portion 1400c extends from the trailing edge 1402 substantially perpendicular to the pressure surface 1403 of the adjacent diffuser vane 1401B. It is formed. The pressure surface 1403 means the entire surface of the diffuser vane 1401 from the front edge 1412 to the trailing edge 1402 facing outward in the radial direction. By forming such a notch portion 1404, a substantially triangular notch 1405 penetrating in the axial direction Ax (see FIGS. 3 and 4) is formed on the outer peripheral edge portion of the diffuser outer bottom surface portion 1400c. There is. In other words, the outer peripheral edge of the diffuser 1400 is formed so as to be serrated along the circumferential direction.

As shown in FIG. 6, when the diffuser 1400 is attached to the fan casing 52, a substantially triangular continuous passage 1420 formed by the fan casing 52, the diffuser vane 1401, and the notch 1404 is formed. Further, on the outer circumference of the diffuser 1400 in the radial direction, substantially triangular passages 1420 are formed side by side in the circumferential direction. The upstream side of the communication passage 1420 communicates with the diffuser flow path 1410 surrounded by the

adjacent diffuser vanes

1401, 1401, the diffuser outer bottom surface portion 1400c, and the fan cover 51 (see FIGS. 3 and 4). When the centrifugal impeller 300 rotates in the W direction, air (fluid) is discharged from the outer circumference of the centrifugal impeller 300.

Further, the discharged air passes through the diffuser flow path 1410 (see the arrow) and flows into the substantially triangular continuous passage 1420, and the scroll flow path 70 provided on the back side of the diffuser 1400 (in the direction perpendicular to the paper surface in FIG. 6). It flows into the back side).

The air flowing through the scroll flow path 70 passes through the scroll portion 75 and is discharged to the discharge portion 76. Then, the air that has passed through the discharge portion 76 passes through the casing discharge port 59 and is introduced into the introduction path 72. The discharge unit 76 means a scroll flow path 70 from the point B to the casing discharge port 59.

As shown in FIG. 7, in the blower provided with the conventional diffuser 1400, although the cross-sectional area of the communication passage 1420 is constant, the outer diameter of the trailing edge 1402 of the diffuser vane 1401 is a constant value, so that the blower has a constant value with the trailing edge 1402. The distance S100 from the radial outer wall surface 74 increases in the rotation direction W of the centrifugal impeller 300. As a result, between the trailing edge 1402 of the diffuser vane 1401 and the radial outer wall surface 74 of the fan casing 52, the flow of air passing through the diffuser flow path 1410 is not constrained by the radial outer wall surface 74, and thus this region (distance). A high pressure recovery rate cannot be obtained in the gap of S100).

Within the constraints of mounting such a blower, in order to obtain pressure recovery more efficiently, it is necessary to increase the length of the diffuser vane 1401 as much as possible and increase the pressure recovery rate in the diffuser 1400. It is extremely important in the design of the blower. Further, in such a case, it is necessary to change the flow path cross-sectional area of the communication passage 1420 for guiding from the outlet of the diffuser flow path 1410 to the scroll flow path 70 in the circumferential direction (toward the rotation direction W). is there. This is to suppress the pressure loss due to sudden contraction / expansion when passing through the communication passage 1420.

Next, the structure of the blower 22 of the first embodiment will be described with reference to FIGS. 8 to 10. FIG. 8 is a plan view of the diffuser of the first embodiment. FIG. 9 is a plan view of a blower equipped with the diffuser of the first embodiment, showing a state in which the fan cover is removed. FIG. 10 is a schematic view showing a communication passage formed by the diffuser of the first embodiment. The shape of the diffuser 400 shown below is an example, and is not limited to the first embodiment.

As shown in FIG. 8, the blower 22 of the first embodiment (see FIGS. 3 and 4) is provided with a diffuser 400 in place of the diffuser 1400 of the conventional example (see FIG. 5 and FIG. 7). .. In this diffuser 400, the lengths of the diffuser vanes 401 are different in the circumferential direction. More specifically, the position of the front edge 412 of the diffuser vane 401 is the same in the circumferential direction, but the position of the trailing edge 402 is different in the radial direction.

Further, in the diffuser 400, in the region indicated by the reference numeral R1 (range of 90 °), a plurality of diffuser vanes 401 are arranged at equal intervals in the circumferential direction around the bottom plate 400a as in the conventional example. The reference position (position at 0 °) of the region R1 is a line passing through the tip of the tongue end portion 71 and the rotation center O of the centrifugal impeller 300. The diffuser vane 401 stands up in the axial direction Ax (see FIGS. 3 and 4) (direction toward the front side perpendicular to the paper surface in FIG. 8) with respect to the diffuser outer bottom surface portion 400c formed around the bottom plate 400a. Is formed. Further, the diffuser vane 401 is located outside the outer peripheral edge portion of the centrifugal impeller 300 (see FIGS. 3 and 4).

The diffuser vane 401 is formed in a thin plate shape and extends in the circumferential direction in a plan view. Further, in the diffuser vane 401, the trailing edge 402 (the other end or the outer diameter side end) is located radially outside the front edge 412 (one end or the inner diameter side end). Further, in the diffuser vane 401A (401) of the region R1, the front edge 412 of the diffuser vane 401B (401) adjacent to the diffuser vane 401B (401) is located substantially in the center in the circumferential direction and inside the radial direction of the diffuser vane 401A. There is. In other words, in the diffuser vane 401B (401), the trailing edge 402 of the diffuser vane 401A (401) adjacent to the diffuser vane 401B (401) is located substantially in the center in the circumferential direction and outside in the radial direction of the diffuser vane 401B. Further, a diffuser flow path 410 described later is formed between the adjacent diffuser vanes 401A and 401B. The diffuser flow path 410 is configured so that the width in the radial direction gradually increases from the front edge 412 side to the trailing edge 402 side.

Further, in the diffuser vane 401A (401), the notch portion 404 is provided so that the outer peripheral edge portion of the diffuser outer bottom surface portion 400c extends from the trailing edge 402 substantially perpendicular to the pressure surface 403 of the adjacent diffuser vane 401B. It is formed. The pressure surface 403 means the entire surface of the diffuser vane 401 from the front edge 412 to the trailing edge 402 facing outward in the radial direction. By forming such a notch portion 404, a substantially triangular notch portion 405 penetrating in the axial direction Ax is formed on the outer peripheral edge portion of the diffuser outer bottom surface portion 400c. In other words, the outer peripheral edge of the diffuser 400 in the region R1 is formed so as to be serrated along the circumferential direction.

Further, in the diffuser 400 in the region R2 (range of 90 °), the diffuser vanes 401 having the same length in the circumferential direction are arranged at equal intervals in the circumferential direction (rotational direction W) as in the reference numeral R1. ..

Further, the diffuser 400 in the region R3 (range of 90 °) is configured to become longer as the diffuser vane 401 approaches the rotation direction W. Specifically, the diffuser vane 401D is formed longer in the rotation direction W than the adjacent diffuser vanes 401C. The diffuser vanes 401E are formed longer in the rotation direction W than the adjacent diffuser vanes 401D. The diffuser vanes 401F are formed longer in the rotation direction W than the adjacent diffuser vanes 401E. The diffuser vanes 401G are formed longer in the rotation direction W than the adjacent diffuser vanes 401F. The diffuser vane 401H is formed longer in the rotation direction W than the adjacent diffuser vanes 401G.

Further, some diffusers 400 in the region R4 (range of 90 °) are configured to become longer as the diffuser vane 401 approaches the rotation direction W. Specifically, the diffuser vane 401J is formed longer in the rotation direction W than the adjacent diffuser vanes 401I. The diffuser vanes 401K are formed longer in the rotation direction W than the adjacent diffuser vanes 401J. The diffuser vanes 401L are formed longer in the rotation direction W than the adjacent diffuser vanes 401K.

Further, the diffuser 400 in the other portion in the region R4 (range of 90 °) is configured to become shorter as the diffuser vane 401 approaches the rotation direction W. Specifically, the diffuser vane 401M is formed shorter in the rotation direction W than the adjacent diffuser vanes 401L. The diffuser vanes 401N are formed so as to have the same length in the rotation direction W as the adjacent diffuser vanes 401M. The diffuser vanes 401M and 401N are formed longer in the rotation direction W than the diffuser vanes 401 in the region indicated by reference numeral R1.

Further, in the diffuser 400, in the region R4, the diffuser outer bottom surface portion 400c is formed so as to extend to the trailing edge 402 of the

diffuser vanes

401J, 401K, 401L. Further, the diffuser 400 extends radially outward from the trailing edge 402 of the diffuser vane 401M in the region R4. As described above, the diffuser 400 has an arc portion 400c1 in which the diffuser outer bottom surface portion 400c is formed in a substantially arc shape over the

diffuser vanes

401J, 401K, 401L, 401M, and 401N in the region R4. In other words, the diffuser 400 has a shape (a shape other than the saw blade shape) in which the communication passage 420 is not formed in a part of the region R4.

As shown in FIG. 9, when the diffuser 400 is mounted on the fan casing 52, the tip (rear edge 402) of the diffuser vane 401N comes into contact with the tongue end portion 71. Further, the arc portion 400c1 (hub wall surface) of the diffuser outer bottom surface portion 400c extends toward the casing discharge port 59 (outlet of the scroll flow path 70).

Further, in the first embodiment, the position of the tongue end portion 71 of the scroll flow path 70 is used as a reference, and the length of the diffuser vane 401 in the circumferential direction is longer in the rotation direction W of the centrifugal impeller 300 from there. More specifically, in the first embodiment, when the position P1 connecting the tip of the tongue end portion 71 and the rotation center O of the centrifugal impeller 300 is set as a reference (0 °), 90 in the rotation direction W from the reference position P1. Let P2 be the position rotated by °, P3 be the position rotated 180 ° in the rotation direction W from the reference position P1, and P4 be the position rotated 270 ° in the rotation direction W from the reference position P1. The positions P1 to P2 correspond to the above-mentioned region R1. The position P2 to the position P3 correspond to the above-mentioned region R2. The position P3 to the position P4 corresponds to the above-mentioned region R3. The position P4 to the position P1 corresponds to the above-mentioned region R4.

As described above, in the first embodiment, between 0 ° and 180 ° (regions R1 and R2 in FIG. 8), the diffuser vane 401 having the same length in the rotation direction W is obtained, and the diffuser vane 401 is from 180 ° to 270 °. In the space (region R3 in FIG. 8), the length of the diffuser vane 401 is gradually increased in the rotation direction W. Further, in the first embodiment, the length of the diffuser vane 401 is gradually increased in a part in the rotation direction W from 270 ° to 360 ° (0 °) (region R4 in FIG. 8). It is configured in. Further, in the first embodiment, in the range from 270 ° to 360 ° (0 °) (region R4 in FIG. 8), the length of the diffuser vane 401 in the rotation direction W in the other portion (the remaining part). Is configured to be shorter.

Further, in the first embodiment, the length of the diffuser vane 401 in the circumferential direction is formed to be the same at the position P1 at 0 ° and the position P2 at 90 °. Further, the length of the diffuser vane 401 in the circumferential direction is formed to be the same at the position P2 at 90 ° and the position P3 at 180 °. At the 180 ° position P3 and the 270 ° position P4, the diffuser vane 401 at the 270 ° position P4 is formed longer than the diffuser vane 401 at the 180 ° position P3.

Further, in the first embodiment, the diffuser vane 401 is formed long in the rotation direction W so as to fill the distance S100 (see FIG. 7) in the conventional example. As described above, the blower 22 of the first embodiment (see FIGS. 3 and 4) is particularly effective when the radial outer wall surface 74 (see FIG. 9) of the fan casing 52 changes in the circumferential direction. When the mounting space of the blower 22 (see FIGS. 3 and 4) in the product is limited as in the washing machine S (see FIG. 1), the radial outer wall surface 74 of the fan casing 52 is circular. Cannot be secured.

Therefore, in the first embodiment, as shown in FIG. 10, the longer the diffuser flow path 410 of the diffuser vane 401, the larger the flow path cross-sectional area of the communication passage 420 needs to be. That is, the flow path cross-sectional area of the communication passage 420 also increases in the circumferential direction (rotational direction W) so as to correspond to the diffuser vane 401 that becomes longer in the circumferential direction (rotational direction W).

In this case, the trailing edge 402 of the diffuser vane 401 may be in contact with or separated from the radial outer wall surface 74 of the scroll flow path 70. The more in contact, the longer the diffuser vane 401 can be made, resulting in higher efficiency. However, since it is often difficult to make contact from the viewpoint of product assembly, a gap of about several mm may be provided. When such a gap is provided, the gap width S1 (see FIG. 9) between the trailing edge 402 of the diffuser vane 401 and the outer wall surface 74 in the radial direction is preferably a constant value in the circumferential direction.

Further, when flowing from the diffuser flow path 410 through the communication passage 420 and the scroll flow path 70 into the introduction path 72 (see FIG. 9), the flow flows directly from the diffuser flow path 410 into the introduction path 72 without passing through the communication passage 420. Where possible (see region R4a in FIG. 9), the pressure recovery rate is higher and the efficiency is higher when the flow is directly flowed into the introduction path 72. In other words, the diffuser 400 is provided with a diffuser flow path 410A (see FIG. 9) which does not have a communication passage 420 in the region R4a which can be directly connected to the introduction path 72 in the diffuser flow path 410. As a result, the air flow through the diffuser flow path 410A is directly guided to the introduction path 72 without being converted from the radial direction to the axial direction Ax. As a result, the pressure loss due to the conversion of the air flow can be suppressed, and the efficiency of the blower 22 can be improved.

As described above, the blower 22 of the first embodiment includes the electric motor 100, the rotating shaft 101 rotatably provided on the electric motor 100, the centrifugal impeller 300 provided on the rotating shaft 101, and the downstream of the centrifugal impeller 300. A diffuser flow path 410 composed of diffuser vanes 401 arranged in the circumferential direction and a scroll provided downstream of the diffuser flow path 410 on the opposite side of the axial direction Ax with respect to the diffuser flow path 410. A flow path 70 is provided. With reference to the tongue end portion 71 of the scroll flow path 70, the circumferential length of the diffuser vane 401 changes as the rotation direction W of the centrifugal impeller 300 is directed (see FIG. 9). That is, in the region R3, the diffuser vane 401 is formed longer toward the rotation direction W. Further, in a part of the region R4, the diffuser vane 401 is formed longer toward the rotation direction W. According to this, when the radial outer wall surface 74 (see FIG. 9) of the fan casing 52 changes in the circumferential direction (for example, when the scroll flow path 70 expands in the radial direction in the circumferential direction), the diffuser flow. The flow of air passing through the road 410 can be restrained, and a high pressure recovery rate can be obtained. As a result, even when the scroll flow path 70 is arranged on the side opposite to the axial direction Ax with respect to the diffuser vane 401 to reduce the size of the blower 22, the efficiency of the blower 22 can be improved.

Further, in the first embodiment, the length of the diffuser vane 401 in the circumferential direction increases toward the rotation direction W of the centrifugal impeller 300 with the tongue end portion 71 as a reference position (see FIG. 9). According to this, in a shape in which the scroll flow path 70 expands in the rotation direction W, the flow of air passing through the diffuser flow path 410 can be restrained, and a high pressure recovery rate can be obtained.

Further, in the first embodiment, the cross-sectional area of the communication passage 420 connecting the diffuser flow path 410 and the scroll flow path 70 changes in the rotation direction W of the centrifugal impeller 300 (see FIG. 10). According to this, it is possible to suppress the pressure loss due to the sudden contraction / expansion when passing through the communication passage 420, and it is possible to further improve the efficiency of the blower 22.

Further, in the first embodiment, the cross-sectional area of the communication passage 420 connecting the diffuser flow path 410 and the scroll flow path 70 increases in the rotation direction W of the centrifugal impeller 300 (see FIG. 10). According to this, in a shape in which the scroll flow path 70 expands in the rotation direction W, it is possible to suppress a pressure loss due to sudden contraction / expansion when passing through the communication passage 420, and further improve the efficiency of the blower 22. be able to.

Further, in the first embodiment, at the outlet of the scroll flow path 70, there is a diffuser flow path 410A that does not have a communication passage 420 connecting the diffuser flow path 410 and the scroll flow path 70 (see FIG. 9). According to this, the air flow through the diffuser flow path 410 is directly guided to the introduction path 72 without being turned from the radial direction to the axial direction. As a result, the pressure loss due to the conversion of the air flow can be suppressed, and the efficiency of the blower 22 can be improved.

Further, in the first embodiment, the electric motor 100, the rotating shaft 101 rotatably provided on the electric motor 100, the centrifugal impeller 300 provided on the rotating shaft 101, and the centrifugal impeller 300 provided downstream of the centrifugal impeller 300 are provided in the circumferential direction. It includes a diffuser flow path 410 composed of the arranged diffuser vanes 401, and a scroll flow path 70 provided downstream of the diffuser flow path 410 on the side opposite to the axial direction Ax with respect to the diffuser flow path 410. .. When the straight line connecting the rotation center O of the centrifugal impeller 300 and the tongue end 71 of the scroll flow path 70 is 0 °, the length L of the diffuser vane 401 (see FIG. 8) is the rotation direction W of the centrifugal impeller 300. Is positive, the position P4 at 270 ° is different from the position P2 at 90 ° and the position P3 at 180 ° (at least one position at 90 °, 180 °, 270 °). ). According to this, when the radial outer wall surface 74 (see FIG. 9) of the fan casing 52 changes in the circumferential direction (for example, when the scroll flow path 70 expands in the radial direction in the circumferential direction), the diffuser flow path The flow of air that has passed through the 410 can be constrained, and a high pressure recovery rate can be obtained. As a result, even when the scroll flow path 70 is arranged on the side opposite to the axial direction Ax with respect to the diffuser vane 401 to reduce the size of the blower 22, the efficiency of the blower 22 can be improved.

Further, in the first embodiment, the length L of the diffuser vane 401 (see FIG. 8) satisfies the relationship of 0 ° position P1 = 90 ° position P2 = 180 ° position P3 <270 ° position P4. According to this, in a shape in which the scroll flow path 70 expands in the rotation direction W, the flow of air passing through the diffuser flow path 410 can be restrained, and a high pressure recovery rate can be obtained.

(Second Embodiment)
FIG. 11 is a perspective view of a blower equipped with the diffuser of the second embodiment. Note that FIG. 11 shows a state in which the fan cover 51 is removed, as in FIG. 9.
As shown in FIG. 11, the blower of the second embodiment includes a diffuser 400A instead of the diffuser 400 of the first embodiment.

In the diffuser 400A, in addition to the configuration in which the diffuser outer bottom surface portion 400c is close to the radial outer wall surface 74 of the scroll flow path 70, the diffuser outer bottom surface portion 400c extends further to the introduction path 72 on the outer diameter side of the discharge portion 76. The formed diffuser outer extension bottom surface portion 400d is provided. The diffuser outer extension bottom surface portion 400d is formed in the vicinity of the wall surface 74a formed so as to extend continuously from the radial outer wall surface 74 from the discharge portion 76 toward the introduction path 72, and from the tongue end portion 71. It is formed close to the wall surface 74b extending toward the introduction path 72 so as to face the wall surface 74a.

As a result, in the introduction path 72, the diffuser outer extension bottom surface portion 400d plays a role of a kind of guide vane, and the pressure can be recovered more efficiently even in the introduction path 72. In particular, when the mounting space of the blower 22 is limited as in the washing machine S, the rate of change in the cross-sectional area of the flow path from the casing discharge port 59 to the outlet of the introduction path 72 tends to increase. As a result, the flow in the introduction path 72 is separated from the wall surface, and the pressure loss becomes large. In order to prevent this pressure loss, the flow control by extending the diffuser outer extension bottom surface portion 400d to the introduction path 72 is effective for improving efficiency.

Further, the diffuser outer extension bottom surface portion 400d is provided with a diffuser vane extension portion 406 that extends a part of the diffuser vane 401 to the introduction path 72 on the outer diameter side of the discharge portion 76. The diffuser vane extension portion 406 is formed up to the edge portion (end portion) of the diffuser outer extension bottom surface portion 400d on the introduction path 72 side. By additionally providing such a diffuser vane extension portion 406, a higher rectifying effect can be obtained.

Further, the diffuser outer extension bottom surface portion 400d is provided with a guide vane 407 formed continuously from the inside of the scroll flow path 70 to the introduction path 72 via the discharge portion 76 on the scroll flow path 70 side on the back surface. The addition of such a guide vane 407 is also effective in obtaining a high rectifying effect.

In the first embodiment and the second embodiment, the blower 22 is provided in the washing machine S (see FIG. 1). As a result, the mounting power is good and the input power to the blower 22 during the drying operation can be reduced, so that the washing machine S with reduced power consumption can be provided. Further, since the size can be reduced in the radial direction, when the blowers 22 of the first and second embodiments are mounted on a washing machine having the same housing, a sound absorbing material or the like can be installed in an empty space in the radial direction, and the washing machine. It becomes possible to reduce the noise.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, in the above-described embodiment, the case where the length of the diffuser vane 401 in the circumferential direction increases in the rotation direction W has been described as an example, but the length of the diffuser 401 in the circumferential direction tends to be in the rotation direction W. It may have a structure that becomes smaller.

Further, in the second embodiment, the case where one diffuser vane extension portion 406 is provided has been described as an example, but a configuration in which a plurality of diffuser vane extension portions are provided may be provided.

Further, in the second embodiment, the case where one guide vane 407 is provided has been described as an example, but a configuration in which a plurality of guide vanes are provided may be used.

Further, the diffuser vane 401 at the 90 ° position P2 may have a longer circumferential length than the diffuser vane 401 at the 0 ° position P1. Further, the diffuser vane 401 at the 180 ° position P3 may have a longer circumferential length than the diffuser vane 401 at the 90 ° position P2.

1 Outer frame 2 Outer tank 3 Rotating tank 22 Blower 51 Fan cover 52 Fan casing 57 Suction port 59 Casing discharge port (outlet part of scroll flow path)
61 Casing part 70 Scroll flow path 71 Tongue end part (tongue part)
72, 72a, 72b Introductory path 74 Radial outer wall surface 75 Scroll part 76 Discharge part 90 Elastic member 100 Electric motor 101 Rotating shaft 300 Centrifugal impeller (impeller)
400,400A Diffuser 400c Diffuser outer bottom surface 400d Diffuser outer extension bottom surface 401,401A Diffuser vane (vane)
402 Trailing edge 406 Diffuser vane extension (vane extension)
407 Guide vane 410 Diffuser flow path 412 Front edge 420 Continuous passage Ax Axial direction P10 ° position P2 90 ° position P3 180 ° position P4 270 ° position S Washing machine W Rotation direction

Claims

With an electric motor
A rotating shaft rotatably provided on the motor and
An impeller provided on the rotating shaft and
A diffuser flow path provided downstream of the impeller and composed of vanes arranged in the circumferential direction,
Downstream of the diffuser flow path, a scroll flow path provided on the side opposite to the axial direction of the rotation axis with respect to the diffuser flow path is provided.
A blower characterized in that the length of the vane changes as the impeller rotates in the direction of rotation with respect to the tongue portion of the scroll flow path.
In the blower according to claim 1,
A blower characterized in that the circumferential length of the vane increases in the rotational direction of the impeller with the tongue portion as a reference position.
With an electric motor
A rotating shaft rotatably provided on the motor and
An impeller provided on the rotating shaft and
A diffuser flow path provided downstream of the impeller and composed of vanes arranged in the circumferential direction,
Downstream of the diffuser flow path, a scroll flow path provided on the side opposite to the axial direction of the rotation axis with respect to the diffuser flow path is provided.
When the straight line connecting the center of rotation of the impeller and the tongue of the scroll flow path is 0 °, the length of the vane is 90 ° and 180 ° with the rotation direction of the impeller as positive. A blower characterized in that it differs at at least one position at a position of 270 °.
In the blower according to claim 3,
The blower is characterized in that the length of the vane satisfies the relationship of 0 ° position ≤ 90 ° position ≤ 180 ° position <270 ° position.
In the blower according to claim 1 or 3.
A blower characterized in that the cross-sectional area of a communication passage connecting the diffuser flow path and the scroll flow path changes in the rotational direction of the impeller.
In the blower according to claim 5,
A blower characterized in that the cross-sectional area of the communication passage connecting the diffuser flow path and the scroll flow path increases in the rotational direction of the impeller.
In the blower according to claim 1 or 3.
A blower characterized in that at least one diffuser flow path having no communication path connecting the diffuser flow path and the scroll flow path exists at the outlet of the scroll flow path.
In the blower according to claim 1 or 3.
A blower characterized in that a hub wall surface forming the diffuser flow path is formed so as to extend to the outside from an outlet portion of the scroll flow path.
In the blower according to claim 8,
A blower characterized in that a vane extension portion extending the vane is formed on the hub wall surface.
In the blower according to claim 8,
A blower characterized in that a guide vane is formed on the wall surface of the hub from the scroll flow path toward the outside of the outlet portion on a surface opposite to the vane.
A washing machine provided with the blower according to claim 1 or 3.