JP3199931B2 - Outdoor unit of air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outdoor unit used for an air conditioner, and more particularly to an outdoor unit having a bell mouth and a fan guard with reduced noise.

[0002]

2. Description of the Related Art In recent years, it has been desired to greatly reduce the blowing noise while improving the blowing efficiency of a fan in an outdoor unit as well as an indoor unit for air conditioning due to a demand for a comfortable environment. Therefore, in the outdoor unit of the air conditioner, a heat exchanger is arranged on the front side of the main body case, an axial fan is arranged on the opposite side, and a bell mouth that covers the peripheral surface of the fan and a fan guard that covers the outer surface of the bell mouth are installed. Provided. In order to improve fan efficiency and reduce noise, bell mouth parts have been mainly improved. In this case, the bell mouth is formed integrally with an inlet bell mouth portion, a cylindrical main air guiding portion, and an outlet bell mouth portion from a suction side provided in the main body case, and a peripheral edge of the outlet bell mouth portion. Is provided with a cylindrical regulating wall for preventing the formation of a short-circuit channel for the flow toward the outside of the front surface of the main body case. This example is described in Japanese Utility Model Laid-Open No. 4-95228.

[0003]

In the above-mentioned outdoor unit of the conventional air conditioner, the bell mouth of the fan, especially on the outlet side, is improved to cause an increase in blowing noise and a reduction in the amount of blowing air. In addition, the formation of a short-circuit channel is prevented, and the efficiency of the outdoor unit for air conditioning is improved. ◆ However,
In this conventional example, the inside of the fan guard other than the bell mouth at the entrance and the exit is provided with a cylindrical regulating wall for preventing the formation of a short-circuit channel, and the bell mouth form becomes complicated and the production cost is high There was a problem of becoming.

An object of the present invention is to improve the performance of an outdoor unit of an air conditioner and reduce noise with a simple configuration without increasing the manufacturing cost.

[0005]

In order to achieve the above object, the present invention provides an indoor heat exchanger, an axial fan for blowing air exchanged by the indoor heat exchanger, and an axial fan. A bell mouth that covers the outer peripheral surface of the axial flow fan and extends downstream from near the rear edge of the axial flow fan, and a plurality of grids having different vertical and horizontal pitches
In the outdoor unit of the air conditioner provided with the formed fan guard , the bell mouth has a stepped prism shape such that the downstream side expands , and the fan guard is equal to the downstream end of the bell mouth.
And the axial length of the rectangular part is 4
0 mm or more, space with bell mouth and fan guard
A part is formed.

[0006]

As a result, bellmouth and fan guard
Since more space is formed, this space allows
The vortex chamber was formed on the flow side, and the bell mouth 6 and the axial flow
The turbulent noise generated between the fans 5 can be further reduced.
Wear.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. First, the unit configuration of the outdoor unit for air conditioning will be described with reference to FIG. The outdoor unit body case 1 is divided into a machine room 9 provided with a compressor and the like by a partition plate 8 and a blower room 10 for performing heat exchange using a fan. The heat exchanger 2 is arranged on one side of the blowing chamber 10,
The blower chamber 1 of the outdoor unit body case 1 on the front surface
The fan motor holding pedestal 4 is fixed in the inside. An axial fan 5 attached to the motor 3, a bell mouth 6 for covering the outlet side outer peripheral surface of the axial flow fan 5 and rectifying the suction flow, and a fan guard for covering the outer surface of the air outlet of the fan. 7 are mounted in the outdoor unit main body case 1. Here, the wind 11 sucked through the heat exchanger 2 passes through a space defined by the motor 3 and the blower chamber 10, is rectified by the bell mouth 6, and is driven by the motor 3. The air is sucked into the fan 5, and then becomes a discharge flow 12, and the air is blown into the blower chamber 1 of the outdoor unit body case 1.
It is discharged through the fan guard 7 out of zero.

FIG. 1 is a detailed view of the vicinity of an axial fan installed in a blower chamber of an outdoor unit of the air conditioner shown in FIG. The air 11 that has passed through the heat exchanger 2 installed in the ventilation chamber 10
The air is sucked by the axial fan 5 into a tape-shaped bell mouth 6 integrally formed with the outdoor unit main body case 1. Here, the air in the bell mouth forms a vortex 13 in the taper portion, and the vortex draws in the air in the blower chamber 10 and discharges the air through the fan guard 7 to the outside. Here, the turbulent sound generated between the bellmouth and the fan is reduced by the vortex formed in the tape portion of the bellmouth.

FIG. 2 shows an example of a lattice-type fan guard used in the embodiment of FIG. 1, which is formed in a rectangular shape and protrudes from the outer wall surface of the main body case 1. Further, it is composed of a plurality of vertical grids 14 and horizontal grids 15, and the number of horizontal grids is smaller than the number of vertical grids. Further, it is a rectangular lattice having different vertical and horizontal pitches, and its inner dimension in the width and height directions is smaller than the minimum inner diameter Db of the bell mouth 6.
It is made of a plate material having a length of 1.08 to 1.1 × Db or more and an axial length of 20 mm or more. By combining this fan guard with the tape-shaped bell mouth 6 of FIG. 1, the formation range of the vortex 13 is limited to the inner wall 16 of the fan guard 7 on the downstream side of the fan.
To improve the performance of the fan. Further, Fanga - flow 12 discharged from the de-7, the vertical grid of being rectified in the axial flow, the flow leaving the fan guard 7
Short circuit that goes to heat exchanger 2 side is eliminated
Thus, it is possible to prevent the flow of the flow toward the heat exchanger, which is generated in the blower using the conventional circular fan guard.

FIG. 5 is a modification of FIG. In this example, the bellmouth shape close to the fan guard is not a taper shape as in FIG. 1 but a stepped prism shape.
The axial length of the fan guard 7 is at least twice as long as that of FIG. This stepped bell mouth 6 parts and wanger
Since the swirl chamber can be formed on the downstream side of the fan by the space formed by the bulge of the door 16, the turbulent noise generated between the bell mouth 6 and the axial fan 5 is further reduced.

FIG. 6 shows still another modification of FIG.
This embodiment differs from the embodiments of FIGS. 1 and 5 in that the bellmouth shape has a constant curvature on the upstream side and a constant inner diameter on the downstream side. At this time, the fan is installed at a position almost coincident with the lowermost end of the bell mouth. In addition, the axial length of the fan guard 7 is doubled or more as compared with the embodiment of FIG. 1 to secure the flow space inside the fan guard 16 and to help the formation of the vortex 13. Thereby, noise at the bell mouth part can be reduced.

[0013]

As described above, according to the present invention, since a vortex can be formed in the bell mouth and on the downstream side thereof, the efficiency of the fan can be improved and the fluid noise can be reduced.

[0014]

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional view of one embodiment of an outdoor unit of an air conditioner of the present invention.

FIG. 2 is a front view of the grid type fan guard shown in FIG. 1;

FIG. 3 is a partial longitudinal sectional view of a conventional fan guard.

FIG. 4 is a longitudinal sectional view of one embodiment of the outdoor unit of the air conditioner of the present invention.

FIG. 5 is a view showing a modification of FIG. 1;

FIG. 6 is a diagram showing a modification of FIG. 1;

[Explanation of symbols]

1: Outdoor unit main body case, 2: Heat exciter,
5: axial fan, 6: bell mouth, 7:
Fungard.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Joji Okamoto 390 Muramatsu, Shimizu-shi, Shizuoka Pref.Hitachi, Ltd. Air Conditioning Systems Division (72) Inventor Koji Sakuma 390 Muramatsu, Shimizu-shi, Shizuoka Pref. (72) Inventor Minato Izushi 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Inside Air Conditioning Systems Division, Hitachi, Ltd. (72) Inventor Yoshihiko Mochizuki 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Hitachi Shimizu Engineering Co., Ltd. (56) References JP-A-3-48539 (JP, A) JP-A-5-202898 (JP, A) JP-A-5-132336 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24F 5/00

Claims (1)

(57) [Claims] 1. An indoor heat exchanger, an axial fan for blowing air exchanged by the indoor heat exchanger, and a downstream side from the vicinity of a rear edge of the axial fan that covers an outer peripheral surface of the axial fan. A bellmouth that extends to the side and multiple grids with different vertical and horizontal pitches are formed
In the outdoor unit of the air conditioner having the formed fan guard , the bell mouth has a stepped prism shape such that the downstream side is enlarged , and the fan guard is a downstream end of the bell mouth.
Rectangular shape of the same size as the part, and the axial direction of the rectangular part
The length is 40 mm or more, and the bell mouth and the fan
An outdoor unit of an air conditioner, wherein a space is formed by a guard .