JPH07293495A - Fan - Google Patents

Abstract

PURPOSE:To lessen the detrioration in the propeller fan perform-ance caused by deformation of a rotating propeller fan blade, restricting an increase in the cost. CONSTITUTION:The thickness of a blade at both a range 21 from a position at which a leading edge of a blade part 2a of a propeller fan 2 is joined with a cylindrical supporting part 2b to the middle part of the leading edge and a range 22 along a band combining respective middle points of leading and following blade edges, starting a position at which the leading edge is joined with the cylindrical supporting part 2b, is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propeller fan for a blower.

[0002]

2. Description of the Related Art FIG. 8 is a block diagram of a conventional blower, FIG. 9 is an external view of a propeller fan, and FIG. 10 is a sectional view of the propeller fan. In FIG. 8, 1 is a duct that forms an air passage for conveying air, 2 is a propeller fan that rotates to convey air, 3 is a bell mouth that covers the periphery of the propeller fan 2, and 4 is the propeller. A fan motor 5 for rotating the fan 2 is a motor support for fixing the fan motor 4. In FIG. 9, the propeller fan 2 includes a blade portion 2a that conveys air, a cylindrical support portion 2b that supports the blade portion 2a, and a circular support body 2.
c, an insert portion 2d for inserting the motor rotation shaft 4a of the fan motor 2 for giving a rotational movement, a radial shape for fixing the insert portion 2d to a cylindrical support portion 2b, and a circular support body 2c. The support portion 2e is arranged and is fixed to the motor rotating shaft 4a with a screw 6 as shown in FIG. In addition, the propeller fan 2
The blade portion 2a has a thickness distribution shown in FIG. 11, and the mounting relationship between the blade portion 2a and the cylindrical support portion 2b is the mounting angle γ as shown in FIG. Further, as shown in FIG. 9, of the blade portions 2a, 2a1 is referred to as a leading edge of the blade portion, 2a2 is referred to as a trailing edge, and 2a3 is referred to as a blade tip.

Next, the operation will be described. When the fan motor 4 is driven, the motor rotating shaft 4a and the propeller fan 2 rotate, and the air is discharged to the outside after passing through the duct 1. At this time, the blade portion 2a of the propeller fan 2 and the cylindrical support portion 2 are
Maximum stress and maximum strain are generated at the position shown in FIG. 13 in b due to the centrifugal force during rotation, and the blade portion 2a is deformed as shown in FIG.

By the way, when the blower is installed locally, the blower itself often requires space saving,
Also, when combined with a local connection air passage, the operating point of the blower often deviates from the specified value. Therefore, in FIG. 15, fb is the PQ characteristic curve of the propeller fan, gb
Is the K-Q characteristic curve, and the pressure loss curve is P1 →
When it changes to P2 (in this case, decreases), the operating point is d → d
In some cases, the propeller fan 2 cannot be used at an operating point where the specific noise is low.

[0005]

Since the conventional blower is constructed as described above, the blade 2a is deformed during operation, so that the design performance cannot be sufficiently achieved. Also,
If the thickness of the blade portion is made uniform to suppress the deformation, the maximum stress generated will be large, and in order to suppress this, the thickness of the maximum stress generating portion will be further increased, and there has been a problem that the cost is increased.

Further, when the blower is installed, the pressure loss in the air passage may change, so that the propeller fan cannot be used at a point where the specific noise is low, and the noise cannot be suppressed to the minimum. There was a problem that the flow rate was insufficient.

Further, in terms of space saving, there is a problem in that the size of the blower cannot be suppressed below the propeller fan height + fan motor height due to its structure.

The present invention has been made to solve the above problems, and to reduce the deterioration of the propeller fan performance due to deformation when the propeller fan rotates while suppressing an increase in cost, and to install a blower. The purpose of the present invention is to make it possible to sufficiently achieve the performance at the time of designing a propeller fan even if the pressure loss in the air passage changes, and to minimize the size of the blower.

[0009]

The blower according to the present invention is, at least, from the vicinity of the position where the front edge of the propeller fan blade portion joins with the support portion supporting the blade portion to the center portion of the front edge or the front portion. The deformation preventing means is provided on either one of the areas connecting the vicinity of the edge where the edge is joined to the supporting portion and the vicinity of the central position of the blade tip.

Further, as the deformation preventing means, the thickness of the wing portion is locally increased.

Further, as a deformation preventing means, the cross section of the wing portion is locally bent.

Further, the supporting portion for supporting the blade portion is used as a hollow supporting portion, and a support body for preventing the deformation of the hollow supporting portion is attached to the joining position of the hollow supporting portion with the front edge portion of the propeller fan blade portion. It is a thing.

Further, the supporting portion for supporting the blade portion is a hollow supporting portion, and the inner dimension of the hollow supporting portion of the propeller fan is made larger than the outer dimension of the fan motor, and the fan motor is inserted inside the hollow supporting portion. is there.

Further, when the propeller fan blade portion is mounted on the support portion for supporting the blade portion, the mounting angle varying means for varying the mounting angle, and the mounting angle varying means,
After selecting the mounting angle, mounting angle fixing means for fixing the mounting angle of the wing portion is provided.

Further, at a predetermined position on the joint surface of the propeller fan blade portion which is joined to the joint plane of the support portion which supports the blade portion,
An attachment angle varying means for providing a rotating shaft that allows the blade portion to rotate on a joint plane of the support portion, and rotating the blade portion around the rotation axis to select a predetermined attachment angle, and the blade. A concave portion including a protrusion or a hole is provided on the side of the joint surface of the portion facing the joint plane of the hollow support portion, and the protrusion or the hole of the wing portion is provided on the joint plane of the support portion with the wing portion. The mounting angle is fixed by providing a recess or a protrusion including a hole at a position corresponding to the recess including the protrusion and the recess including the protrusion of the blade or the recess including the hole of the support portion. And means are provided.

Further, a mounting angle varying means composed of a joined body of a plurality of propeller fan blades to which the propeller fan blades are attached by changing the mounting angles respectively, and a joined body of the propeller blades having a desired mounting angle are selected. And an attachment angle fixing means formed by fixing the wing portion to the joint plane of the supporting portion.

[0017]

In the blower according to the present invention, the deformation preventing means is provided around the maximum strain generating portion of the propeller fan blade portion.
The strength of the blades increases, the stress and strain generated during rotation, and the displacement of the blades can be reduced, and the deterioration of the performance of the propeller fan can be prevented.

Further, as a means for preventing deformation of the propeller fan blade portion, the thickness of the blade portion is locally thickened around the maximum strain generating portion, so that the blade portion strength is increased and the cost increase is suppressed while the blade portion is generated during rotation. It is possible to reduce the applied stress and strain, and the amount of displacement of the blade, and prevent the performance of the propeller fan from deteriorating.

Further, as a means for preventing the deformation of the propeller blade portion, since the blade portion is locally bent around the maximum strain generating portion, the strength against the deformation of the blade portion is increased,
It is possible to reduce the amount of displacement of the blades during rotation, prevent the cost from rising, and prevent the performance of the propeller fan from deteriorating.

Further, since the support member for preventing the deformation of the hollow supporting portion is attached to the joining position of the blade leading edge portion of the hollow supporting portion,
While making the propeller fan lightweight by making the support part hollow, the cross section formed by the hollow support part and the support for deformation prevention is L-shaped, has sufficient strength, and deformation of the hollow support part can be reduced during rotation, The deformation of the propeller fan can be reduced, and the deterioration of the performance of the propeller fan can be prevented.

The blower size can be reduced by making the inner dimension of the hollow support portion of the propeller fan larger than the outer dimension of the fan motor and inserting the fan motor inside the hollow support portion.

Further, since the mounting angle varying means for varying the mounting angle for mounting the propeller fan blade portion to the supporting portion for supporting the blade portion and the mounting angle fixing means after the mounting angle is determined are provided, for example, when the blower is installed. Even if the pressure loss in the air passage changes, the installation angle can be changed and the blower performance at the time of design can be sufficiently achieved.

Further, since the rotating shaft is provided on the joint surface of the propeller blade portion, the propeller fan blade portion can be freely rotated around the rotating shaft to make the mounting angle variable, and the joint surface and blade of the blade portion can be changed. The selected mounting angle can be fixed by fitting a concave portion including a protrusion or a hole provided on the joining plane of the supporting portion that supports the portion.

Further, since the joint body of the propeller fan blades to which the propeller fan blade portions are attached by changing the mounting angle is provided, the joint plane of the supporting portion for supporting the blade portion by selecting the joint body of the desired mounting angle. Can be fixed to.

[0025]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings, and the same or corresponding portions as those of the conventional machine will be designated by the same reference numerals and the description thereof will be omitted. FIG. 1 shows a blade portion 2 of a propeller fan 2.
The position and cross-sectional shape which increased thickness compared with the conventional machine of a are shown. The position is shown in FIG. 1A and the cross-sectional shape is shown in FIG. Here, as a means for preventing the deformation of the blade portion, a range 21 from the position where the front edge of the blade portion 2a of the propeller fan 2 joins the cylindrical support portion 2b, which is a support portion for supporting the blade portion, to the center portion of the front edge 21. Further, the thickness of the blade portion in the range 22 connecting the front edge with the cylindrical support portion 2b and the blade tip center position is locally thickened around the maximum strain generation portion as shown in FIG. .

By increasing the thickness of the blades, the amount of deformation of the propeller fan 2 during rotation can be reduced, and the design performance can be secured. That is, it is possible to suppress a decrease in the air volume, and it is possible to suppress an increase in noise with the same air volume.

Example 2. As shown in FIG. 2, as a means for preventing deformation of the wing portion that achieves the same effect as that of the first embodiment, as shown in FIG.
2 (b) and (c) are cross-sectional views of the range 21 and the range 22 shown in FIG.
The bent structure shown in FIG. With the same structure, the same operational effect as that of the first embodiment can be obtained.

Third Embodiment FIG. 3 shows a cylindrical support 2 which is a hollow support for supporting the blades of the circular support 2c of the propeller fan 2 and the fan motor 4 in the first embodiment.
It is arranged on the opposite end face of b, the inner diameter is made larger than the outer diameter of the fan motor 2, and the insert portion 2d and the radially-arranged support portion 2e are set to the minimum length at which the motor rotating shaft 4a is sufficiently fitted into the insert portion 2d. The fan motor 4 is shortened and the fan motor 4 is housed in the cylindrical support portion 2b.

With the above structure, the cross section of the cylindrical support 2b and the circular support 2c is L-shaped, and the front edge of the propeller fan blade is joined to the cylindrical support. The cylindrical support part has sufficient strength to prevent deformation during rotation, which reduces the deformation of the propeller fan while ensuring design performance, lowering airflow and increasing noise. Can be suppressed. Further, the height of the blower is reduced, the size can be reduced, and space can be saved.

The structure of locally increasing the thickness of the blade as the deformation preventing means, the structure of locally bending the cross section of the blade, and the front edge of the blade of the cylindrical supporting portion. The structure for attaching the deformation-preventing support to the joining position has the above-mentioned effects even if each is taken individually, but by combining any two sets or all of them, the above-mentioned effects can be obtained.
It will become more prominent.

Example 4. 4 and 5 show the blade portion 2a and the cylindrical support portion 2b of the propeller fan 2 according to the first embodiment that are individually configured. In FIG. 4, a portion of the cylindrical support portion 2b that is in contact with the wing portion 2a is a joint plane 2f. Further, the joint surface 2g of the blade portion 2a with the support portion 2b is a plane surrounded by the blade surface 2h and the chord line 2i, and the blade portion attachment angle varying means serves as a blade portion at the chord length halving point. Two
A rotary shaft 2k with a thread groove for rotatively moving a with respect to the support portion 2b and fixing it with a nut 2j from the back side of the support portion 2b is arranged, and also the mounting angle fixing means of the wing portion. As projections 2L and 2m on the blade leading edge side and the trailing edge side of the joining surface 2g respectively,
A bearing hole 2n through which the rotary shaft 2k of the blade portion 2a passes, and recesses 2o and 2p into which the protrusions 2L and 2m are fitted are provided at positions facing the protrusions 2L and 2m, respectively. A plurality of recesses 2o and 2p are provided at regular intervals so that the blade 2a changes its mounting angle at a constant angle with respect to the support 2b. Therefore, the optimum mounting angle can be selected for the pressure loss change in the air passage.

FIG. 6 shows the specific noise when the operating point of the propeller fan 2 is deviated when the mounting angle of the blade portion 2a is large or small. In the figure, fa and ga are the PQ characteristic curve and the KQ characteristic curve, respectively, when the mounting angle is small, and fb and gb are the above curves when the mounting angle is large. When the pressure loss curve is P1, the specific noise is d <c and the type B specific noise is low, but the pressure loss curve is P1.
→ When changing to P2, the specific noise of type B is d → d ',
It can be seen that the specific noise of type A is c → c ′, and d ′> c ′, and the magnitude relationship of the specific noises of the two types of propeller fans is reversed. Therefore, the mounting angle of the blade portion 2a for minimizing the noise is different due to the pressure loss of the duct, and the noise can be reduced by changing the mounting angle. That is, even if the pressure loss in the air passage changes during the installation of the blower, the performance at the time of designing the propeller fan can be sufficiently achieved by selecting the mounting angle.

As the mounting angle varying means, the rotary shaft 2k is arranged at the halves of the chord length, but with this structure, the variable range of the blade mounting angle can be widened, and the shaft can be handled. Although there is an advantage that the operation is easy, the rotation axis 2k is at any position on the chord, or
Even if the blade is provided at an arbitrary position on the joint surface of the propeller fan and the blade can be rotated on the joint plane of the supporting portion, the effect of changing the mounting angle can be obtained. Further, as the mounting angle fixing means, on the opposite side to the rotary shaft 2k,
Providing the protrusion 2L and the recess 2o and the protrusion 2m and the recess 2p stabilizes the operation of the mounting angle fixing means.
With respect to the rotary shaft 2k, the role of fixing the mounting angle is sufficiently achieved even on only one side. Further, even if a concave portion is provided on the joint surface 2g and a protrusion is provided on the joint plane 2f, the same operation and effect can be obtained.

Example 5. As a means for obtaining the same effect as that of the fourth embodiment, there is a method shown in FIG. In the figure, reference numeral 2a denotes a wing portion which is manufactured by previously changing the attachment angle of the joined body 2s, and is an attachment angle varying means, which is fixed to the cylindrical support portion 2b by the attachment screw 7 which is the attachment angle fixing means. To do. By selecting the joined body 2s having an appropriate mounting angle and fixing it to the cylindrical supporting portion, the same effect as that of the fourth embodiment can be obtained.

In each of the above-mentioned embodiments, the supporting portion for supporting the blade portion constituting the propeller fan is a hollow supporting portion.
Although it has been described as a cylindrical shape, it is not limited to this shape, and may have a polygonal cross section, a cylindrical shape, a partially provided joint plane at equal intervals, and the like.
Any shape may be used as long as the wing portion 2a can be attached and supported and can be smoothly rotated by the motor rotation shaft. The cylindrical shape has the advantage of being lightweight and easy to manufacture, and the polygonal shape of the cross section makes it easy to form the joining plane in the fourth and fifth embodiments. Further, the supporting part may be a cylindrical supporting part, that is, a columnar one instead of the hollow supporting part, except for the fourth and fifth embodiments.

[0036]

Since the present invention is constructed as described above, it has the following effects.

At least from the vicinity of the position where the leading edge of the propeller fan blade portion joins the support portion supporting the blade portion to the center of the leading edge or from the portion where the leading edge joins the support portion to the blade tip. Since the deformation prevention means is provided on either side of the area connecting the vicinity of the central position, the strength of the maximum strain generation area of the propeller fan blade is increased and the deformation of the blade during rotation is reduced. It is possible to prevent deterioration of the performance of the propeller fan.

Further, as the deformation preventing means, the thickness of the blade portion is locally increased, so that the strength of the maximum strain generation region of the blade portion is increased and the deformation of the blade portion during rotation can be reduced. It is possible to prevent the performance of the propeller fan from being deteriorated while suppressing the cost increase, and to prevent the decrease of the air volume and the deterioration of the noise performance.

Further, as the deformation preventing means, the cross section of the blade portion is locally bent, so that the strength of the maximum strain generation region of the blade portion is increased and the deformation of the blade portion during rotation is reduced.
It is possible to prevent a decrease in air flow of the propeller fan and deterioration of noise performance while suppressing cost increase.

Further, a supporting portion for supporting the blade portion is used as a hollow supporting portion, and a support body for preventing the deformation of the hollow supporting portion is attached to a joint position of the hollow supporting portion with the front edge portion of the propeller fan blade portion. With this configuration, the propeller fan can be made lighter in weight, and deformation of the joint position between the hollow support and the blade front edge can be prevented, thus reducing the deformation of the propeller fan, reducing air flow and deteriorating noise performance. It can be prevented.

Further, the supporting portion for supporting the blade portion is a hollow supporting portion, the inner dimension of the hollow supporting portion of the propeller fan is made larger than the outer dimension of the fan motor, and the fan motor is inserted inside the hollow supporting portion. So it's lighter,
A blower having a small size and a small space can be obtained.

Further, since the mounting angle varying means for changing the mounting angle for mounting the propeller fan blade portion to the supporting portion for supporting the blade portion and the mounting angle fixing means after the mounting angle is selected are provided, it is possible to install the blower. Even if the pressure loss in the air passage changes, the installation angle can be changed and the blower performance at the time of design can be sufficiently achieved.

Further, since the rotating shaft is provided on the joint surface of the propeller blade portion, the propeller fan blade portion can be freely rotated around the rotating shaft to make the mounting angle variable, and the joint surface and blade of the blade portion can be changed. The selected mounting angle can be fixed by fitting the concave part including the protrusion or hole provided on the joint plane of the support part that supports the part. Even if the loss changes, by selecting the mounting angle of the propeller fan, the performance at the time of fan design can be secured, and the flow rate shortage and noise performance deterioration can be prevented.

Further, a joint body of the propeller fan blade portions to which the propeller fan blade portions are attached by changing the attachment angle is provided, and the joint body having a desired attachment angle is selected and fixed to the joint plane of the supporting portion supporting the blade portions. With this configuration, even if the pressure loss in the air passage changes when the blower is installed, it is possible to prevent the flow rate from being insufficient and the noise performance to be deteriorated by selecting the joined body having the desired mounting angle.

[Brief description of drawings]

FIG. 1 is a shape diagram of a propeller fan according to a first embodiment of the present invention.

FIG. 2 is a shape diagram of a propeller fan according to a second embodiment of the present invention.

FIG. 3 is a structural diagram of a propeller fan according to Embodiment 3 of the present invention.

FIG. 4 is a structural diagram of a propeller fan according to a fourth embodiment of the present invention.

FIG. 5 is a detailed structural diagram of a propeller fan according to a fourth embodiment of the present invention.

FIG. 6 is an operation state diagram of a propeller fan according to a fourth embodiment of the present invention.

FIG. 7 is a structural diagram of a propeller fan according to Embodiment 5 of the present invention.

FIG. 8 is a configuration diagram of a conventional blower.

FIG. 9 is an external view of a conventional propeller fan.

FIG. 10 is a view showing a conventional propeller fan installation state.

FIG. 11 is a view for explaining a blade portion of a conventional propeller fan.

FIG. 12 is a view showing a state where blades and supporting portions of a conventional propeller fan are attached.

FIG. 13 is a stress / strain distribution diagram of a conventional propeller fan during rotation.

FIG. 14 is a modification view of a conventional propeller fan when rotating.

FIG. 15 is an operation state diagram of a conventional propeller fan.

[Explanation of Codes] 2 Propeller fan 2a Blade part 2b Support part (hollow support part) 2c Support body 2f Joining plane 2g Joining surface 2k Rotating shaft 2L Projection part 2m Projection part 2o Recess part containing hole part 2p Recess part containing hole part 2s Junction 4 Fan motor

Claims (8)

[Claims] 1. A blower comprising a propeller fan composed of a wing portion that makes a rotary motion to convey air and a support portion that supports the wing portion, and a fan motor that rotatably drives the propeller fan, wherein the propeller is at least the propeller. Either from the vicinity of the position where the leading edge of the fan blade portion is joined to the support portion to the center portion of the leading edge, or along the region connecting the vicinity of the position where the leading edge joins the support portion and the neighborhood of the blade tip center position. A blower, characterized in that deformation preventing means is provided on one side. 2. The blower according to claim 1, wherein the vane portion is locally thickened as the deformation preventing means. 3. The blower according to claim 1, wherein the blade section has a locally bent shape as the deformation preventing means. 4. A blower comprising a propeller fan composed of a wing part that makes a rotary motion for conveying air and a hollow support part that supports the wing part, and a fan motor that rotatably drives the propeller fan. A blower, wherein a support member for preventing deformation of the hollow support portion is attached to a position where the hollow support portion is joined to a front edge portion of the propeller fan blade portion. 5. A blower comprising a propeller fan having a rotative movement for conveying air and a supporting portion for supporting the wing portion formed of a hollow support portion, and a fan motor rotatably driving the propeller fan, A blower characterized in that the inner dimension of the hollow support portion of the propeller fan is made larger than the outer dimension of the fan motor, and a fan motor is inserted inside the hollow support portion. 6. A blower comprising a propeller fan composed of a blade portion that performs a rotary motion for conveying air and a support portion that supports the blade portion, and a fan motor that rotationally drives the propeller fan, wherein the propeller fan blade is provided. A mounting angle varying means for varying the mounting angle when mounting the portion to the supporting portion; and a mounting angle fixing means for fixing the mounting angle of the wing portion after the mounting angle is selected by the mounting angle varying means. A blower characterized by being provided. 7. A rotary shaft that allows the blade section to rotate on the joint plane of the support section at a predetermined position on the joint plane of the propeller fan blade section that joins with the joint plane of the support section that supports the blade section. A mounting angle varying means for providing a predetermined mounting angle by rotating the wing portion around the rotation axis, and a protrusion on the side of the joint surface of the wing portion facing the joint plane of the support portion or Providing a concave portion including a hole portion, in the joint plane with the wing portion of the support portion, provided in a concave portion or a protrusion portion including a hole portion at a position corresponding to the protrusion portion of the wing portion or the concave portion including a hole, The mounting angle fixing means for fitting a recessed portion including a protrusion or a hole of the wing portion with a recessed portion or a protrusion including the hole of the support portion is provided. Blower. 8. A mounting angle varying means comprising a joined body of a plurality of propeller blade portions to which propeller blade portions are attached with different mounting angles respectively, and a joined body of the propeller blade portions having a desired mounting angle are selected. 7. The blower according to claim 6, further comprising mounting angle fixing means for fixing the blade to a joint plane of the supporting portion that supports the blade portion.