JP4915791B2 - Centrifugal multiblade blower - Google Patents

Description

  The present invention relates to a centrifugal multiblade fan.

Centrifugal multiblade fans used in air blowers such as air conditioners for vehicles have a cylindrical fan that is lined up on the outer periphery and driven to rotate in the circumferential direction by a motor, and stores the fan in a radial pattern. And a scroll-shaped scroll casing that rectifies the air flow discharged to the air and blows it out in one direction.
In the centrifugal multi-blade blower, if the air flow is disturbed in the spiral flow path on the outer peripheral side of the fan, noise is generated and the efficiency is reduced. Therefore, technical development for suppressing the turbulent flow has been performed. .

Therefore, a configuration is disclosed in which the cross-sectional area of the spiral flow path of the scroll casing is gradually enlarged from the upstream side to the downstream side (see Patent Document 1).
JP 2003-193998 A

However, in the technique disclosed in Patent Document 1, the secondary flow discharged from the fan and colliding with the outer peripheral wall and deflected in the spiral flow path is directed toward the intake port, and a reverse flow is generated near one side of the blade of the fan. There is a problem of letting.
As a result, problems such as an increase in flow loss in the spiral flow path and a decrease in fan efficiency or generation of noise occur.

  The present invention has been made to solve such problems, and the object of the present invention is to satisfactorily rectify the secondary flow in the spiral flow path, thereby improving fan efficiency and reducing noise. An object of the present invention is to provide a centrifugal multiblade fan that can be suppressed.

In order to achieve the above object, in the centrifugal multi-blade fan of claim 1, a fan having a cylindrical shape, a plurality of blades arranged in an outer peripheral portion, and having one axial end opened, and the fan A motor that rotationally drives to one side in the circumferential direction, a fan that houses the fan and the motor, and a side wall that has an intake port that corresponds to the opening of the fan, and is spaced apart from the one side wall in the axial direction of the fan The other side wall formed in this manner and the outer peripheral edge of the one side wall and the other side wall are connected, and the winding angle to one side in the circumferential direction increases with a predetermined radial direction as a reference position with respect to the axis of the fan. the distance between the axis is formed from the outer peripheral wall formed in a spiral shape to increase, with these one side wall, and a scroll casing that spiral flow path at the outer peripheral side of the fan is formed by the other side wall and the outer wall, a plane Said one side in view Rotational direction of the with blades extending to the outer peripheral side to the outer circumferential side or from the outside of the said blade from the area provided, the and outer peripheral direction and the fan extending a predetermined length in the axial direction of the other side from the one side wall and has a plan view shape extending in is characterized in that extended shape der Ru guide vanes plan view shape of the blade has a plurality arrayed in the circumferential direction.

The centrifugal multiblade blower according to claim 2, in claim 1, a predetermined length from said one side wall of the guide vanes in the axial direction the other side, the length from the one side wall to the axial center position of the blade It is shorter than that.
The centrifugal multiblade fan according to claim 3 is characterized in that, in claim 1 or 2, the guide blade is separated from the outer peripheral wall.

In 請 Motomeko 4 of the centrifugal multi-blade fan, in any one of claims 1 to 3, wherein the guide vane is formed so as to enlarge toward the outer peripheral side from the interval the inner periphery of the guide vanes adjacent It is characterized by that.

The centrifugal multiblade blower according to claim 5, in any one of claims 1 to 4, wherein the guide vane is formed in a shape in which the inner peripheral side along the outer shape of the blade one side, one side of the blade It is characterized by extending from the position in the outer peripheral direction and the rotation direction of the fan.
The centrifugal multiblade blower according to a sixth aspect is characterized in that, in any one of the first to fifth aspects, an outer peripheral portion of the one side wall bulges to one side in the axial direction from the guide blade.

The centrifugal multiblade blower according to claim 7, in any one of claims 1 to 6, wherein the other side wall, the portion forming the spiral flow path is characterized by bulges in the axial direction of the other side .

According to the centrifugal multiblade blower according to claim 1 to 5 of the present invention using the above means, the outer peripheral portion of at least the fan blades one side wall of the scroll casing forming the spiral flow path, given the axial direction other side A plurality of guide blades extending in the circumferential direction and having a shape corresponding to the blades are arranged in the circumferential direction, so that the secondary flow flowing from the other side to the one side in the spiral flow path by the guide blades is rotated in the direction of rotation of the fan. Can be rectified well.

  Further, the guide vanes can rectify the air flow discharged from one side portion of the blade to the outer peripheral side in the air flow discharged from the fan in the rotation direction of the fan, and the interval between adjacent guide blades. Is spread from the inner peripheral side toward the outer peripheral side, so that the kinetic energy of the air flow passing between the guide vanes can be favorably converted into pressure energy, that is, the dynamic pressure can be converted into static pressure.

As described above, the reverse flow or the like caused by the secondary flow can be prevented and the flow loss can be reduced, whereby the efficiency of the fan can be improved and the generation of noise can be suppressed.
According to the centrifugal multiblade fan of claims 6 and 7 , one side and the other side of the spiral flow path are expanded by expanding one side wall and the other side wall of the spiral flow path and expanding the spiral flow path in the axial direction. The side vortex structure can be suppressed, and the flow loss can be further reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Referring to FIGS. 1 to 3, FIG. 1 is a perspective view of a centrifugal multiblade fan according to the present invention, and FIG. 2 is a plan view of the centrifugal multiblade fan according to the present invention as viewed from one axial side of a fan. 3 is a cross-sectional view taken along the line AA in FIG. Hereinafter, a description will be given based on FIG.
The blower 1 is used in a blower unit of a vehicle air conditioner, and is provided on the air flow downstream side of the inside / outside air introduction portion 2 in the ventilation duct (not shown) and the air flow upstream side of the evaporator 4.

The blower 1 mainly includes a fan 10, a motor 20, and a scroll casing 30.
The fan 10 has a cylindrical shape, and a plurality of blades 12 extending in the axial direction are arranged in an outer peripheral portion. The blade 12 has a shape extending from the inner peripheral side to the outer peripheral side while being curved from the inner peripheral side to the one circumferential side in plan view.

Further, one end portion of each blade 12 is connected to a circumferential rim 14 extending in the circumferential direction.
On the other side in the axial direction of the fan 10, an outer peripheral edge portion is connected to an inner peripheral side portion at the other end of each blade 12, and a cone portion having a substantially conical shape bulging toward one side in the axial direction toward the center. 16 is formed. A boss hole 16a is formed in the central portion of the cone portion 16, and the rotating shaft 22 of the motor 20 is fitted in the boss hole 16a.

The motor 20 is provided so as to be housed inside the cone portion 16 of the fan 10, and has a function of rotating the fan 10 in the circumferential direction via the rotating shaft 22 when electric power is supplied.
The fan 10 is rotated to one side in the circumferential direction by the motor 20 to suck air from one side in the axial direction, that is, from the inner circumference of the rim 14, and the air sucked into the inner circumference side is radially emitted to the outer circumference side by the blade 12. Has a function of discharging. In this embodiment, the fan 10 has a clockwise direction as viewed in the plan view of FIG.

The scroll casing 30 houses the fan 10 and the motor 20 in the central portion in plan view.
The scroll casing 30 includes one side wall 32 and another side wall 34 that are spaced apart from each other in the axial direction of the fan 10, and the outer peripheral edges of the one side wall 32 and the other side wall 34 that are parallel to the axial direction of the fan 10. It is comprised from the outer peripheral wall 36 connected and extended.

The outer peripheral wall 36 includes a spiral part 36a, a flat part 36b, a tongue part 36c, and an extension part 36d.
The spiral portion 36a has an axis θ of the fan 10 as a central axis and a predetermined radial direction as a reference position (θ = 0 °), and an angle θ (hereinafter referred to as a winding angle θ) in the rotation direction of the fan 10 from the reference position. As the distance increases, the spiral shape is curved so that the distance from the central axis increases.

The spiral portion 36a extends from a reference position over a predetermined high angle position (for example, θ = 300 °), and after the high angle position, a flat portion 36b extending flat in the tangential direction is formed. Yes.
Further, at the reference position portion, a tongue portion 36c that is curved from the spiral portion 36a toward the outer peripheral side in the radial direction is formed, and the extension portion that extends from the tongue portion 36c toward the outer peripheral side in the radial direction so as to be separated from the flat portion 36b. 36d is formed.

A portion between the outer peripheral wall 36 and the outer periphery of the fan 10 is a spiral flow path 38, and the end of the spiral flow path 38 is the end portion of the flat portion 36 b and the extension portion 36 d of the outer peripheral wall 36 and one side wall 32. And the other side wall 34 has comprised the blower outlet 38a opened to the evaporator 4 side.
The other side wall 34 includes a central surface 34 a corresponding to the position of the fan 10, an outer peripheral surface 34 b corresponding to the spiral flow path 38 portion, and a vertical surface 34 c.

  The central surface 34a and the outer peripheral surface 34b of the other side wall 34 are perpendicular to the axial direction, the central surface 34a is positioned near the other end of the fan 10, and the outer peripheral surface 34b is more axial than the central surface 34a. Located in the other direction. A motor support hole 34d is formed in the central surface 34a, and the motor 20 is supported in the motor support hole 34d via the bracket 24. The vertical surface 34c is parallel to the axial direction and extends in the circumferential direction from the outer peripheral edge of the central surface 34a to the inner peripheral edge of the outer peripheral surface 34b.

The one side wall 32 includes a central surface 32b having an air inlet 32a corresponding to the position of the fan 10, an outer peripheral surface 32c corresponding to the spiral flow path 38, and a vertical surface 32d.
The intake port 32 a of the one side wall 32 forms a circular hole having substantially the same diameter as the inner periphery of the rim 14 of the fan 10. The central surface 32b and the outer peripheral surface 32c are each perpendicular to the axial direction, the central surface 32b is located near one end of the fan 10, and the outer peripheral surface 32c is on the outer peripheral side and axial direction from the central surface in plan view. It is located on one side of the center surface 32b. The vertical surface 32d forms a surface extending in the circumferential direction from the outer peripheral edge of the central surface 34a in parallel to the axial direction and over the inner peripheral edge of the outer peripheral surface 34b.

  Further, the central surface 32b extends in a predetermined width from the opening edge of the air inlet 32a to the outside of the outer periphery of the fan 10 except for the vicinity of the reference position in plan view, and the outer peripheral edge is curved toward the center in the vicinity of the reference position. The width has been reduced. Accordingly, the inner peripheral edge of the outer peripheral surface 32c and the vertical surface 32d are curved toward the center near the reference position, and the distance from the tongue portion 36c is increased.

Furthermore, a plurality of guide blades 40 extending in the other axial direction are provided in the circumferential direction on the central surface 32b of the one side wall.
Specifically, the guide blades 40 are arranged in a line having a number smaller than the number of blades 12 of the fan 10, for example, about one third of the number of blades 12.
The guide blade 40 extends to the outer peripheral edge of the central surface 32b while being curved so as to extend the shape of the blade 12 from the rim portion 14 of the fan 10, that is, the central portion of the blade 12, in plan view. Each blade 12 has a predetermined interval from the adjacent guide vanes 40, and the interval increases as it goes from the inner peripheral side to the outer peripheral side. However, in the vicinity of the reference position where the gap between the outer periphery of the fan 10 and the outer peripheral wall 36 is narrow, the interval between the adjacent guide vanes 40 is enlarged, and the guide vanes 40 are prevented from contacting the outer peripheral wall 36.

Further, the guide vane 40 extends in a predetermined length from the central surface 32b to a predetermined position on one side of the blade 12 in parallel to the axial direction, and the inner peripheral side portion is cut along the shape of the blade one side, that is, the rim 14. It is missing.
Hereinafter, the operation of the centrifugal multiblade fan configured as described above will be described.
In the centrifugal multiblade fan, when the electric power is supplied to the motor 20, the fan 10 rotates through the rotating shaft 22. By the rotation of the fan 10, air is sucked from the air inlet 32 a to the inner peripheral side of the fan 10 through the inner periphery of the rim 14. Then, the air on the inner peripheral side of the fan 10 is radially discharged to the outer peripheral side through the blade 12, and the air is rectified to the outlet 38 a by the spiral flow path 38 of the scroll casing 30 and blown to the evaporator 4 side. The

  Specifically, the air flow sucked into the inner peripheral side of the fan 10 and discharged to the outer peripheral side by the blade 12 is the other side in the axial direction along the shape of the substantially conical cone portion 16 from the intake port 32a and the outer peripheral side in plan view. Is discharged. Then, the air flow collides with the outer peripheral wall 36 in the spiral flow path 38, deflects mainly to one side in the axial direction, and forms the secondary flow Fs that flows to the bulging portion of the one side wall 32, and the air outlet 38 a. Head to.

Here, in the centrifugal multiblade fan, the secondary flow Fs flowing toward the one side wall 32 is guided by the guide vanes 40 and rectified in the direction of the air outlet 38a.
As described above, in the centrifugal multiblade fan, the secondary flow Fs in the spiral flow path 38 can be rectified satisfactorily by providing the guide vanes 40 on the one side wall 32 of the scroll casing 30. It is possible to prevent a backflow or the like caused by the flow Fs and reduce a flow loss.

  In addition, the guide vane 40 rectifies the air flow discharged from the one end side portion of the blade 12 to the outer peripheral side in the air flow discharged from the fan 10 in the direction of the blowout port 38a and Since the interval is widened from the inner peripheral side toward the outer peripheral side, the kinetic energy of the air flow discharged from the blade 12 can be favorably converted into pressure energy, that is, dynamic pressure can be converted into static pressure.

Further, by swelling the one side wall 32 and the other side wall 34 of the spiral flow path 38, the vortex structure on one side and the other side of the spiral flow path 38 can be suppressed, and the flow loss can be reduced.
In addition, since one side wall 32 and the other side wall 34 of the spiral flow path 38 are expanded, the spiral flow path 38 is uniformly expanded in the axial direction. The structure can be suppressed and the flow loss can be further reduced.

From the above, according to the hyperopic multiblade fan according to the present invention, the performance of the fan 10 can be improved and noise can be suppressed.
Although the description about embodiment of the centrifugal multiblade fan which concerns on this invention is finished above, embodiment is not restricted to the said embodiment.
In the above embodiment, the number of the guide blades 40 is about one third of the number of the blades 12 of the fan 10. However, the number is not limited to this, and may be increased or decreased.

In the above embodiment, the guide vane 40 is notched on the inner peripheral side along the shape of one side of the blade 12 and extends from the center position of the blade 12 to the outer peripheral side in plan view. Is not limited to this, and may have a shape extending from the outer peripheral side of the blade.
In the above embodiment, the guide vane 40 has a shape extending a predetermined length parallel to the axial direction. However, the shape of the guide vane is not limited to this, and may be a shape inclined with respect to the axial direction, for example. I do not care.

  Moreover, in the said embodiment, although the outer peripheral surfaces 32c and 34b of the one side wall 32 and the other side wall 34 have comprised the structure which expanded in the axial direction, it is restricted to this about the shape of the said one side wall 32 and the other side wall 34. For example, the entire surface may be a flat surface.

1 is a perspective view of a centrifugal multiblade fan according to the present invention. It is the top view seen from the axial direction one side of the fan of the centrifugal multiblade fan concerning the present invention. It is sectional drawing which follows the AA line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Blower 10 Fan 20 Motor 30 Scroll casing 32 One side wall 32a Inlet port 32b Center surface 32c Outer surface 32d Inclined surface 34 Other side wall 36 Outer wall 38 Spiral flow path 40 Guide vane

Claims (7)

A fan having a cylindrical shape, a plurality of blades arranged in an outer peripheral portion, and having one axial end opened,
A motor that rotationally drives the fan to one side in the circumferential direction;
One side wall that houses the fan and the motor and has an intake port formed corresponding to the opening of the fan, another side wall that is spaced apart from the one side wall in the axial direction of the fan, and the one side The outer peripheral edge of the side wall and the other side wall is connected to form a spiral shape in which the distance from the axial line increases as the winding angle to one side in the circumferential direction increases with a predetermined radial direction as a reference position with respect to the axial line of the fan. A scroll casing having a spiral flow path formed on the outer peripheral side of the fan by the outer peripheral wall formed by the one side wall, the other side wall, and the outer peripheral wall;
In plan view, it extends from the region of the one side wall where the blade is provided to the outer peripheral side or from the outer side to the outer peripheral side, and extends from the one side wall to the other side in the axial direction and extends in the outer peripheral direction. and extend in the direction of rotation of the fan, plan view shape is a centrifugal multiblade, characterized in that the plan view shape extending shape der Ru guide vanes of the blade has a plurality arrayed in the circumferential direction Blower. Wherein the predetermined length from one side wall to the axial direction other side of the guide vane, centrifugal multiblade of claim 1, wherein a shorter length to the axial center of said blade from said one side wall Blower.   The centrifugal multiblade fan according to claim 1 or 2, wherein the guide vanes are separated from the outer peripheral wall. The centrifugal multiblade fan according to any one of claims 1 to 3 , wherein the guide blade is formed so that an interval between adjacent guide blades increases from an inner peripheral side toward an outer peripheral side. The guide vane has an inner peripheral side formed in a shape along an outer shape of one side of the blade, and extends from one side position of the blade in an outer peripheral direction and a rotation direction of the fan. The centrifugal multiblade fan according to any one of 1 to 4 . The centrifugal multiblade fan according to any one of claims 1 to 5 , wherein an outer peripheral portion of the one side wall bulges to one side in the axial direction from the guide vane. The centrifugal multiblade fan according to any one of claims 1 to 6 , wherein a portion of the other side wall that forms the spiral flow path bulges to the other side in the axial direction.

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