JP2000002194A - Propeller fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise emission and enhance air blowing efficiency. SOLUTION: A peripheral edge 3 of a hub 2 is formed in rotational symmetry of approx. an triangle whose projecting ends 2A are rounded in such a constitution that arc-shaped edge portions 4 having a small curvature and arc-shaped edge portions 5 having a large curvature are provided alternately in continuity, and in the part of the edge portion 4 between the projecting ends 2A, a vane 1 is installed in eccentricity toward the side of hub rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propeller fan incorporated in an outdoor unit of an air conditioner and used for blowing air.

[0002]

2. Description of the Related Art As a fan of this type, a fan in which a plurality of blades 1 are mounted on an outer peripheral surface of a cylindrical hub 2 as shown in FIG. 9 is generally used. In the propeller fan PF having such a shape, the air blowing action is mainly performed at the rear end portion on the outer peripheral side of the blade 1, and the air blowing action is performed almost or slowly at the inner circumferential portion near the hub 2. Absent.

[0003] Since most of the air blown by the propeller fan PF is concentrated on the rear end portion on the outer peripheral side of the blade 1 where the blowing operation is performed, the flow velocity of the air at this portion is high, and when the air leaves the blade 1 The noise of the sound increases.

Further, the hub 2 of the blade 1 having almost no blowing action
At the inner peripheral portion, the air flow is disturbed under the influence of air flowing at high speed on the outer peripheral side, and a part of the air is sucked from the vicinity of the front end 1A of the mounting portion of the blade 1 with low pressure. The noise is further increased by flowing back to the side.

[0005] For this reason, a propeller fan in which noise is reduced by providing a bulging portion on the hub or providing a notch and an auxiliary wing is disclosed in, for example, Japanese Utility Model Publication No. 1-21198 and Japanese Patent Application Laid-Open No. 3-88999. It has been proposed in gazettes and the like.

[0006]

However, actual fairness 1-2
In the propeller fans proposed in Japanese Patent Application Laid-Open No. 1198 and Japanese Patent Application Laid-Open No. 3-88999, etc., it is hard to say that the noise has been sufficiently reduced, and further noise reduction has been demanded. In addition, there is a problem that the structure of the conventional propeller fan in which the hub is processed is complicated,
There was a need to reduce noise without complicating the structure. Furthermore, due to the recent problem of global warming, it has been necessary to solve the above-mentioned problems and at the same time to save energy, that is, to improve the blowing efficiency.

[0007]

According to the present invention, in order to solve the above-mentioned problems of the prior art, the periphery of a hub which is rotationally driven by a rotating means is formed in a rotationally symmetric shape other than a circle, and adjacent protruding ends are formed. A propeller fan of a first configuration in which the blades are attached one by one to the periphery of the hub between them,

[0008] In the propeller fan of the first configuration, the peripheral edge of the hub is formed by continuously connecting arc-shaped curves having different curvatures, and the blades are attached to the peripheral edge of the long hub having a small curvature. With a propeller fan of the configuration

In the propeller fan of the first or second configuration, a propeller fan of a third configuration in which the blades are attached to the rotating side of the peripheral edge between adjacent protruding ends of the hub in a one-sided manner. Is provided.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG. Note that, in order to facilitate understanding, in these figures, parts having the same functions as the parts described in FIG. 9 are denoted by the same reference numerals.

The propeller fan PF of the present invention is formed by integral molding of, for example, a plastic such as polypropylene or acrylonitrile-styrene copolymer. The peripheral edge 3 of the hub 2 to which the blades 1 are attached has an arc-shaped peripheral edge 4 having a small curvature and an arc-shaped peripheral edge 5 having a large curvature are alternately provided, and a plurality of projecting ends 2A are rounded. It is formed in a triangular rotationally symmetric shape.

The adjacent protruding ends 2A.2 of the hub 2
A blade 1 is attached to a portion of a long arc-shaped peripheral edge 4 having a small curvature between A and is shifted to a side on which the hub 2 rotates.

A long blade 1 with a small curvature is attached from the center of the hub 2 in which the mounting hole 6 for inserting and fixing the rotating shaft 21 of the electric motor 20 of the outdoor unit 100 is formed. Reinforcing ribs 7A and 7B reaching the arc-shaped peripheral edge 4 are provided.

The rib 7A is biased toward the front end 1A of the attachment portion of the blade 1 located on the side on which the hub 2 rotates to the hub 2;
Is offset to the rear end 1B of the blade 1 located on the opposite side of the front end 1A of the mounting portion to the hub 2 and between the front end 1A of the mounting portion of the blade 1 and the mounting end of the rib 7A. Is smaller than the dimension between the rear end 1B of the mounting portion of the blade 1 and the mounting end of the rib 7B.

Since the propeller fan PF of the present invention is constructed as described above, when it is rotated by the electric motor 20 in the direction of the arrow, the hub 2 formed in a substantially triangular shape.
Since the air is compressed to a high pressure at a portion located on the side rotating from the protruding end 2A of the protruding end 2A, the pressure becomes low at the opposite side.
As shown in FIG. 4, part of the air flowing on the outer peripheral side of the blade 1 flows on the inner peripheral side near the hub 2.

As a result, the air flows from the outer peripheral portion of the blade 1 toward the hub 2 on an averaged level, and the flow velocity of the air at the rear end of the outer peripheral portion is reduced. Generation of noise when leaving the rear end of the outer peripheral portion is suppressed.

Further, since the air flows at a constant flow rate or more also in the inner peripheral portion of the blade 1 near the hub 2, the blade 1 is attached to the rotating protruding end 2A so as to be offset. In addition, the turbulent flow of air and the backflow of air to the suction side are also eliminated, thereby preventing the generation of noise at the inner peripheral portion near the hub 2.

FIG. 5 is a front view of the present invention at a position 1 m ahead of the front panel in a state where it is attached to an outdoor unit 100 equipped with a compressor 22, a heat exchanger 23, and a bell mouth and a panel (not shown) as shown in FIG. The propeller fan PF of the invention;
The noise was measured and compared with a conventional propeller fan PF in which the peripheral edge 3 of the hub 2 was formed in a cylindrical shape. As can be seen from this comparative diagram, the noise due to the propeller fan PF of the present invention is about 1 dB lower than the conventional propeller fan PF at any air volume.

Further, comparison of the fan motor power consumption between the propeller fan PF of the present invention and the conventional propeller fan PF comparing the noise is performed with the outdoor unit 100 attached.
The measurement results are shown in FIG. As can be seen from this comparison diagram,
The fan motor power consumption by the propeller fan PF of the present invention is smaller at any air volume than the power consumption of the conventional propeller fan PF having the same air volume.

This is because the propeller fan PF of the present invention
Since the peripheral edge 3 of the hub 2 is formed in a substantially triangular shape and the area of the blade 1 is increased, and an effective air blowing action is performed not only on the outer peripheral portion but also on the inner peripheral side of the blade 1, noise reduction and This is an improvement in the total blowing efficiency.

By the way, the shape of the peripheral edge 3 of the hub 2 to which the blades 1 are attached can be formed in a regular triangular state in which the protruding end 2A is pointed as shown in FIG. Further, as shown in FIG. 7B, the hub 2 is formed so that the peripheral edge 3 between the adjacent protruding ends 2A, that is, the arc-shaped peripheral edge 4 having a small curvature is depressed, and the blade 1 is attached to this portion. It can also be configured as follows. Further, as shown in FIG. 7 (c), the connecting portion between the protruding end 2A and the arc-shaped peripheral edge 4 having a small curvature is formed so that the hub 2 is connected smoothly on one side and connected in a bent state on the other side. May be.

Further, as shown in FIGS. 8A to 8D, a hub 2 having four protruding ends 2A is shown in FIG. 7 and the like having three protruding ends 2A. Similarly to the hub 2, the arc-shaped peripheral edges 4 and 5 having different curvatures can be connected to each other.

The hub 2 is formed with five or more protruding ends 2A of the peripheral edge 3 so that the peripheral edge 3 between adjacent protruding ends 2A can be formed.
The blades 1 can be attached to each of them. However, as the number of the protruding ends 2A increases, the effect of compressing the air at the peripheral edge 3 located on the rotation side from the protruding ends 2A to a high pressure becomes poor. On the opposite side, the degree of low pressure becomes small, and the effect of reducing noise and the effect of improving air blowing efficiency are impaired. Therefore, it is not preferable to increase the number of protruding ends 2A too much.

[0024]

As described above, according to the propeller fan of the present invention, there is a remarkable operation and effect that the noise is reduced and the blowing efficiency is improved.

In particular, according to the propeller fan of the third aspect, the backflow of the air to the suction side is also prevented at the inner peripheral portion of the blade near the hub, whereby the noise can be further reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of the present invention, and FIG.
Is a perspective view seen from the front, and (b) is a perspective view seen from the rear.

FIG. 2 is an explanatory diagram of a main part (hub) of one embodiment as viewed from directly behind.

FIG. 3 is an explanatory view showing a state where the propeller fan of the present invention is incorporated in an outdoor unit.

FIG. 4 is an explanatory diagram showing a state in which air flows.

FIG. 5 is an explanatory diagram comparing noise.

FIG. 6 is an explanatory diagram comparing fan motor power consumption.

FIG. 7 is an explanatory diagram showing the shape of the hub as viewed from directly behind.

FIG. 8 is an explanatory diagram showing the shape of the hub as viewed from directly behind.

FIG. 9 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 blade 1A front end of mounting portion 1B rear end of mounting portion 2 hub 2A protruding end 3 peripheral edge 4 arc-shaped peripheral edge having small curvature 5 arc-shaped peripheral edge having large curvature 6 mounting hole 7A / 7B rib 8 air streamline 20 electric motor 21 Rotating shaft 22 Compressor 23 Heat exchanger PF Propeller fan 100 Outdoor unit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshinori Toya 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Shigeya Ishigaki 2-chome, Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd. (72) Inventor Kiyoshi Koyama 2-5-5 Sanyo Electric Co., Ltd. (72) Inventor friend Koizumi 2 Keihanhondori, Moriguchi, Osaka 3-5-3 Sanyo Electric Co., Ltd. F term (reference) 3H033 AA02 AA18 BB02 BB08 CC01 DD03 DD12 EE06 EE19

Claims (3)

[Claims] 1. The peripheral edge of a hub driven by a rotating means is formed in a rotationally symmetric shape other than a circle, and the blades are attached one by one to the peripheral edge of the hub between adjacent protruding ends. Characteristic propeller fan. 2. The propeller fan according to claim 1, wherein the periphery of the hub is formed by connecting arc-shaped curves having different curvatures continuously, and the blades are attached to the periphery of the hub having a small curvature and long. . 3. The propeller fan according to claim 1, wherein the blades are attached to the rotating side of the peripheral edge between the adjacent protruding ends of the hub in a one-sided manner.