JP3203923B2 - Blower impeller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thick airfoil impeller having a low noise effect and having a reduced weight while maintaining performance.

[0002]

2. Description of the Related Art A conventional thick airfoil fan has a structure as shown in FIG. That is, a plurality of thick and airfoil-shaped blades 2 are provided around a substantially cylindrical hub 3. As a blower, the impeller 1 is housed in an appropriate casing, and is rotated in the direction of the arrow to generate a blowing action. The impeller 1 rotates by fixing a motor shaft to an impeller hub 3.

However, since the blades 2 have a certain thickness, the blades 2 are conventionally made by foam molding to prevent the resin from shrinking. Therefore, the blade 2 was solid as shown in FIG.

[0004]

However, the blower having the above-described structure has much lower noise than a thin blower, but the weight is significantly heavy because the blades are solid and thick, and the resin molding time is long. . In other words, foam molding for preventing shrinkage requires a large amount of resin and is extremely heavy. for that reason,
The material cost is high and the resin molding time is long because the time required for cooling the resin by cooling the impeller 1 on the mold, that is, the cooling time is long. The longer molding time results in higher costs. SUMMARY OF THE INVENTION The present invention solves these problems of a remarkable increase in weight, a long molding time and an increase in material cost, and maintains the low noise effect of the airfoil due to the thick wall.

[0005]

In order to solve the above-mentioned problems, an air-grid having a plurality of thick airfoil blades around a hub and having a tapered portion on three sides on the suction side of the blades. The edge is inserted from the inside of the root mean square radius while leaving the outer peripheral side of the suction surface of the blade, and the edge is substantially circular from the position of 15% of the chord length except for the leading edge side of the suction surface of the blade. , Wherein the blade portion other than the edge portion is hollow.

[0006]

The operation of the above means is as follows.

A plurality of thick airfoil blades are provided around the hub, and a grind having a tapered portion on three sides is placed on the suction side of the blades. The agri is inserted, and the leading edge side is left, the agri is inserted from the position of 15% or more of the chord length, and the blade portions other than the agri portion are hollow. And this agri retains the airfoil shape of the blade as much as possible and puts it smoothly,
The low noise effect of the airfoil impeller can be maintained as it is. Also,
The edge portion itself is thin and the blade portion other than the edge portion is hollow, thereby reducing the resin portion and achieving a significant weight reduction. In addition, since the solid portion of the resin is reduced by the edge and the hollow portion, the cooling time in resin molding is reduced to a level equivalent to that of a thin blade. Of course, the amount of resin material is reduced, which results in lower costs.

Further, since the agri is provided on the negative pressure side of the blade in a state where the basic shape of the airfoil is maintained as described above and is smooth, the characteristic of the blade is not promoted by the peeling noise. There is no increase in noise. Therefore, the low noise effect of the thick airfoil can be maintained as it is.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a perspective view of an impeller having an agri 7 of the present invention. FIG. 2 is an AA sectional view of the impeller of the present invention.

The impeller 1 is provided with a blade 2 on a hub 3 on a substantially cylindrical shape.
Is provided. A predetermined edge 7 is provided on the negative pressure surface side of the blade 2 with a small thickness. Fix the motor shaft to the hub part 3 of the impeller 1, put it in a suitable casing,
Rotation in the direction of the arrow by the motor produces a blowing action. At this time, the air enters from the leading edge 4 of the blade 2 and flows out from the trailing edge 5.

In view of this, a taper portion 9 is provided in three directions in the agri 7 on the negative pressure surface side, and the outer peripheral side of the negative pressure surface of the blade 2 is left to be larger than a root mean square u ((R ² + r ² ) / 2). Since the agri 7 is inserted from the inside, the vicinity of the chip 6 on the outer periphery which greatly contributes to the blowing operation in the blower impeller 1 is largely left in the form of an airfoil. Also, leaving the leading edge side of the negative pressure surface of the blade 2,
A substantially circular agri 7 is inserted from a position 15% of the chord length or later. Further, a hollow portion 8 is provided in a portion of the blade 2 other than the edge. As described above, according to the present invention, the agri 7 is thin and is provided smoothly on the negative pressure side of the blade while maintaining the basic shape of the airfoil as described above. Otherwise, the noise is not increased by the agri 7. Therefore, the low noise effect of the thick airfoil can be maintained as it is.

In addition, the thinness of the agri 7 itself and the provision of the hollow portion 8 in the other blade portions reduce the resin portion and achieve significant weight reduction. Since the solid portion of the resin is reduced by the edge 7 and the hollow portion 8, the cooling time on the resin molding is reduced to the same level as the thin blade.
Naturally, the amount of the resin material is reduced, and the cost is reduced.

Here, as a method of applying the hollow portion 8 to the blade, there are a hollow molding method and an ultrasonic welding method in which a portion other than the agri 7 of the blade 2 is divided into thin plates and both are ultrasonic-welded and manufactured. There is.

[0015]

According to the present invention, a plurality of thick airfoil blades are provided around a hub, and three tapered portions are provided on the suction side of the blades.
And the edge is inserted from inside the root mean square radius, leaving the outer peripheral side of the suction surface of the blade, and is substantially more than 15% of the chord length after the leading edge side of the suction surface of the blade is left. An object of the present invention is to provide a blower impeller in which the circular blade-shaped agriculture is inserted and the blade portion other than the agriculture portion is hollow. Therefore, since the solid portion of the resin is reduced by the edge and the hollow portion, the cooling time on the resin molding is reduced to a level equivalent to that of the thin blade, and the amount of the resin material is reduced. As a result, significant weight reduction and cost reduction can be realized.

In addition, the agri is provided on the suction side of the blade.
Since the basic shape of the airfoil is provided smoothly while maintaining the basic shape as described above, the characteristic peeling noise of the blade is not promoted, and the noise is not increased by the edge. Therefore, the low noise effect of the thick airfoil can be maintained as it is.

[Brief description of the drawings]

FIG. 1 is a perspective view of a blower impeller according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a perspective view of a conventional thick airfoil.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 impeller 2 blade 3 hub 4 front edge 5 rear edge 6 chip 7 edge 8 hollow portion 9 tapered portion

Claims (1)

(57) [Claims] 1. A plurality of thick airfoil blades are provided around a hub, and an agri having a tapered portion on three sides is provided on a suction surface side of the blades, and an outer peripheral side of the suction surface of the blades is provided. An impeller that inserts the agriculture from the inside of the remaining root mean square radius and inserts the approximately circular agriculture from 15% of the chord length and beyond, leaving the leading edge side of the suction surface of the blade. A blower impeller with a hollow part in the blade part.