JPH1037895A - Air-conditioning fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control any possible vibration in making the boundary-layer control of flow separation achievable by installing a lot of small holes in plural sheets of blade surface members constituting a fan in a sense of being perpendicular and oblique with a blade surface, and providing a different king member in a hollow layer in the inner part of a blade. SOLUTION: Many small holes 5 are installed in a suction surface 6 and a pressure surface 7 in place nearer to a rear edge 3 of a fan 1. The inner part of a spatial layer held between both these blade surfaces 6 and 7 is composed of an integrally formed different kind member. A flow 8 taken into the fan 1 from a front edge 2 of a blade flow into the small holes 5, producing small vortexes there. These vortexes produced in the small holes 5 are discharged to the outside air form the small holes 5 after having receiving a pressure interference on the surface of the different kind member 4 in the spatial layer. The vortexes discharged to the outside air become lessened of a pressure variation in the blade surface in order to become such a vortex as preventing it from being separated form these surfaces 6 and 7. Therefore it turns to a vibration absorbent by installing the different kind member 4 in the spatial layer being held between these surfaces 6 and 7. Thus, a reduction in fluid noises is made possible, and thus the vibro-noise being generated out of the fan is reducible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 5-196243 discloses a technique for reducing noise generated from the impeller blade surface. In the present technology, a hollow layer is provided inside a plurality of blades constituting a blower impeller, and a large number of small blades in which the hollow layer and the outside communicate with the entire blade or at least a part of the blade pressure surface side and the blade suction surface side. By using a porous pressure fluctuation buffer member having holes or continuous pores, noise generated from the blade surface is reduced.

[0003]

In a structure for controlling a boundary layer on a wing surface as in the prior art, a porous pressure fluctuation cushioning member having a large number of small holes or continuous pores when used for a long period of time has a problem in air. The durability is deteriorated due to the clogging of the holes with dust and aging, and the pressure is reduced, that is, the fan performance is reduced. In addition, it is difficult to mold the porous pressure fluctuation buffer member and the blade on the same blade surface. When the wing is made of a resin member, the vibration from the motor may coincide with the natural frequency of the wing and the vibration noise from the wing may increase depending on the temperature conditions to which the wing is exposed.
In the prior art, since the inside of the blade is merely a hollow layer, it has a role of reducing the blade vibration to some extent, but it is not a technology capable of significantly controlling the vibration.

It is an object of the present invention to provide a reliable structure for controlling the boundary layer of the flow on the wing surface and a control structure for reducing vibration from the motor.

[0005]

In order to achieve the above-mentioned object, the present invention provides a plurality of blade surface members constituting a fan, in which a number of small holes are provided in a direction perpendicular or oblique to the blade surface. The hollow layer inside the communicating wing has a different kind of member different in density from the wing surface member, and the different kind member and the wing are formed by a simultaneous molding method.

[0006] With the configuration according to the present invention, it is possible to control the boundary layer of the separation of the flow, and it is possible to control the vibration by the dissimilar member enclosed in the space layer of the blade.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory view showing an embodiment of the present invention, and FIG. 2 is a sectional view of the propeller-type fan applied to an air-conditioning blower of the present invention. Here, the fan 1 serving as a blowing means includes a motor 11 placed on the same cylindrical surface of the boss 9.
Is inserted into the bearing portion 10 of the boss 9 and is fixed and driven by the motor 11. Reference numerals 4 and 5 denote members different from those of the small hole according to the present invention. A large number of small holes 5 are provided on the suction edge 6 side and the rear edge 3 side of the negative pressure surface of the fan 1 (also referred to as a blade). is there. On the other hand, the heterogeneous member 4 has a negative pressure surface 6.
And a pressure layer 7 and are integrally formed in a space layer.
FIG. 3 shows a case where the small holes 5 are provided only on the negative pressure surface 6 side.

The operation of reducing the noise and vibration of the air conditioning fan according to the present invention will be described with reference to FIGS.

The noise generated by the fan 1 is such that the rotation noise of the fan 1, the fluid noise due to the disturbance of the fluid, and the electromagnetic excitation force accompanying the driving of the motor propagate to the fan 1 via the motor shaft and the bearing of the boss 9. There is a vibration sound that resonates. In the present invention, a small hole is provided in one or both of the wing surfaces 6 and 7 from the trailing edge 3 of the fan 1, and a heterogeneous member 4 integrally formed in a space layer sandwiched between the wing surfaces 6 and 7. First, the flow 8 flowing into the fan 1 from the leading edge 2 of the wing flows into the small hole 5 to generate a small vortex. The vortex generated in the small hole 5 receives pressure interference on the surface of the dissimilar member 4 in the space layer, and is then discharged from the small hole 5 to the outside air. The vortex discharged into the outside air becomes a vortex 15 for preventing the flow of the main flow 8 from peeling off from the wing surfaces 6 and 7, so that pressure fluctuations on the wing surface are reduced and fluid noise can be reduced.
On the other hand, the vibration caused by the electromagnetic excitation force generated from the motor is transmitted directly to the fan 1 via the boss 9 only on the wing surfaces 6 and 7, so that the vibration attenuation effect is small and the fan 1 easily generates a loud sound. . However, by providing the dissimilar member 4 in the space layer sandwiched between the wing surfaces 6 and 7, the dissimilar member becomes a vibration absorber, and the vibration due to the electromagnetic excitation force can be reduced, and the fan 1 generates the vibration. Vibration noise can be reduced. Further, since the dissimilar member is included in the space between the wing surfaces 6 and 7, the range of direct contact with the air is reduced, and the reliability with respect to the life is increased.

A supplementary description of the structure of this embodiment will be given below. FIG. 4 shows one embodiment of the present invention in which a plurality of small holes 5 are provided over the entire surfaces of the wing surfaces 6 and 7.
When the flakes separate near the leading edge 2 of the wing, the flow can be controlled, and the fluid noise can be reduced. FIG. 5 shows a case where the small holes 5 are provided only on the blade surface 6 side of the negative pressure surface with respect to FIG. FIG. 6 shows several partitions 1 in the space layer for the wing configuration of FIG.
6 is shown. FIG. 7 shows a case where a space layer is formed from the thin wing surfaces 6 and 7 and the dissimilar member 4 is interposed therebetween. In each of these figures, the wing member and the dissimilar member 4 in the space layer are integrally formed. FIG. 8 shows a case in which the small holes 5 of the present invention are provided on the outer peripheral surface of the boss 9. The flow peeling around the boss 9 can be suppressed by the small holes 5, and as a result, the fluid noise can be reduced. FIG. 9 is an embodiment of the present invention in which the small hole 5 is not provided on the wing surfaces 6 and 7 and the fan 1 is formed only by different kinds of members in the space layer 4 sandwiched between the wing surfaces 6 and 7. . In the present invention, the boundary layer control of the main flow 8 cannot be performed, but it is possible to reduce the vibration caused by the electromagnetic excitation force. FIG. 10 shows an example in which the embodiment of the present invention is applied to a blade surface of a turbofan other than a propeller fan and a space layer surrounded by the blade surface, and each configuration is the same as FIGS. is there.

[0012]

According to the structure of the present invention, the boundary layer of the flow separation can be controlled, so that the fan noise can be reduced. Electromagnetic vibration can be controlled. Further, while the porous pressure buffer member is exposed to the air as in the prior art, the present invention has a different kind of member sealed inside the wing, so that it is compared with the example shown in the prior art. A highly reliable blade-type air-conditioning blower fan having excellent durability can be provided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram in which an airfoil structure according to an embodiment of the present invention is applied to a propeller fan.

FIG. 2 is a sectional view of an airfoil according to an embodiment of the present invention.

FIG. 3 is a sectional view of an airfoil according to an embodiment of the present invention.

FIG. 4 is a sectional view of an airfoil according to an embodiment of the present invention.

FIG. 5 is a sectional view of an airfoil according to an embodiment of the present invention.

FIG. 6 is a sectional view of an airfoil according to a second embodiment of the present invention.

FIG. 7 is a sectional view of an airfoil according to a third embodiment of the present invention.

FIG. 8 is a sectional view of a boss 9 for mounting the fan 1 according to one embodiment of the present invention.

FIG. 9 is a sectional view of an airfoil according to a fourth embodiment of the present invention.

FIG. 10 is an explanatory diagram in which the airfoil of one embodiment of the present invention is applied to a propeller fan.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fan, 4 ... Different members, 5 ... Small hole, 6 ... Negative pressure surface, 7
... pressure surface, 9 ... boss, 11 ... motor.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Yoshihiko Mochizuki 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Inside Hitachi Shimizu Engineering Co., Ltd. (72) Inventor Hiroyasu Yoneyama 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Hitachi Shimizu Engineering Co., Ltd. (72) Inventor Masatoshi Watanabe 502, Kandachi-cho, Tsuchiura-shi, Ibaraki Pref., Machinery Research Laboratories, Hitachi, Ltd. (72) Inventor Fukuji Tsukada 502, Kantachi-cho, Tsuchiura-shi, Ibaraki Pref., Machinery Research Laboratory, Hitachi, Ltd.

Claims (1)

[Claims] 1. An air-conditioning blower for applying a flow of air by inserting a rotation shaft of a fan drive motor into a shaft hole of a boss member comprising a plurality of blades, wherein a chord length of the plurality of blade surface members is provided. A large number of oblique small holes are provided from 1/2 to the trailing edge toward the vertical or trailing edge direction, and the hollow layer inside the blade that communicates with the small holes has different density from the blade surface member. An air-conditioning blower fan comprising: