HK1050044A - A fan guard for a ventilation device - Google Patents

Description

Fan protection cover of air supply equipment

Technical Field

The present invention relates to a fan protection device, and more particularly to a fan protection cover for an air supply device, which is attached to an air outlet of the air supply device provided with an air supply fan.

Background

As air supply equipment of an outdoor unit of an air conditioner, a fan protection cover is provided at an air supply outlet of an air supply fan. The fan protecting cover is a component for protecting the air supply fan and has a grid structure.

In many conventional fan protection covers, a plurality of radial ribs arranged radially and a plurality of annular ribs arranged concentrically are made of synthetic resin. The synthetic resin fan protecting cover is formed in a slender flat shape along the axial direction of the blower fan in order to maintain strength and reduce pressure loss.

In the conventional fan protection device, if a spiral fan is used as the blower fan, the radiation rib and the annular rib are likely to interfere with the air flow blown from the blower fan into the protection cover. That is, the airflow blown out by the helical fan is a rotational diffused airflow having a predetermined magnitude of velocity component in the rotational direction and the axial direction of the helical fan. Since the radial ribs and the annular ribs are flat along the axial direction of the blower fan, the radial ribs and the annular ribs and the blower airflow blow against the window to generate vortices, which cause pressure loss and also generate noise.

Since the radial ribs are formed at large intervals on the outer circumferential side and the annular ribs are axially flat members, the rigidity on the outer circumferential side becomes weak, and the rigidity in the thickness direction of the fan shroud is also likely to be lowered. If the rigidity in the thickness direction is reduced and snow is accumulated on the fan protecting cover in winter in the up-blowing type outdoor unit, the protecting cover is bent to contact the blower fan.

The invention aims to reduce pressure loss and noise of a fan protection device of an air supply device and maintain and improve the thickness direction rigidity of the fan protection device.

Summary of the invention

Technical means 1a fan protection cover of an air supply device is a fan protection device attached to an air supply outlet of the air supply device with a fan, and is composed of an outer frame, a plurality of 1 st ribs and a plurality of 2 nd ribs. The outer frame is arranged on the periphery of the air supply outlet. The plurality of 1 st ribs are formed by bending radially from the vicinity of the central part of the outer frame to the radial outside along the rotation direction of the blowing fan. The plurality of 2 nd ribs are integrated with the 1 st rib, are arranged concentrically in a ring shape at a predetermined interval in the radial direction with the rotation axis of the blower fan as the center, and at least the outer peripheral side is inclined toward the radial outside along the blowing air flow of the blower fan.

In the fan protection cover of such a blower, the blower fan rotates to generate a rotationally diffused airflow at a predetermined speed in the rotational direction and the axial direction. The blowing air flow passes through the 1 st and 2 nd ribs. In this case, since the 1 st rib is bent in the rotational direction, the blowing air flow diffused along the rotation is bent, so that the blowing air flow does not collide with the 1 st rib, and the blockage of the blowing air flow can be reduced. The 2 nd rib is inclined outward in the radial direction along the blowing air flow, so that the blowing air flow does not collide with the 2 nd rib, and the blockage of the 2 nd rib to the blowing air flow can be reduced. Therefore, even if the 1 st and 2 nd ribs are attached, the blowing air flow can be smoothly blown out, and the pressure loss and noise can be suppressed. Further, since the 2 nd rib is inclined along the flow of the blast air, the width of the 2 nd rib (the length in the direction intersecting the thickness of the 2 nd rib) is longer than that in the case where the width of the 2 nd rib is not inclined, and the rigidity of the fan guard in the thickness direction can be maintained and improved.

The fan guard of the blower device according to claim 2 is the guard according to claim 1, wherein the 1 st rib is inclined toward the downstream side in the rotational direction along the flow of the blower fan. In this case, since the 1 st rib is also inclined along the blowing air flow like the 2 nd rib, the obstruction of the blowing air flow is further reduced, and the pressure loss and the noise can be reduced.

A fan guard cover for an air blowing device according to claim 3 is the guard cover according to claim 2, wherein the inclination angle of the 1 st rib is different from that of the 2 nd rib, and a thickened portion is provided between the 1 st rib and the 2 nd rib at the intersection of the two ribs. At this time, even if the 1 st and 2 nd ribs are inclined outward to generate undercut portions, the undercut portions can be eliminated by the thickened portions. Therefore, the mold can be easily removed, and the fan protection cover can be easily integrally molded by synthetic resin or the like. Further, since the cross-sectional area of the fixing portion of the 2 nd rib where the maximum bending moment becomes large is increased by the thickened portion, the rigidity of the 2 nd rib can be further enhanced, and the rigidity in the thickness direction of the fan guard can be further enhanced.

The fan guard of blower device according to claim 4 is the guard according to claim 2 or 3, wherein the 1 st rib faces the 1 st reference surface parallel to the rotation axis of the blower fan, and the blower side is inclined 20 to 40 degrees toward the downstream side in the rotation direction. In this case, the inclination angle of the 1 st rib is most suitable for the delivery of the whirling blowing airflow.

Technical means 5 the protective cover of air supply equipment is the protective cover of technical means 4, wherein the 2 nd rib is opposite to the 2 nd cylindrical reference surface with the same core of the rotating shaft core of the air supply fan, and the air supply side inclines by 5 to 15 degrees to the outer side. In this case, the inclination angle of the 2 nd rib is most suitable for the diffusion of the blowing air flow.

A protective cover for an air blower according to claim 6 is the protective cover according to any one of claims 1 to 5, wherein the air blowing fan is a helical fan including a cylindrical hub located at the center and a plurality of blades provided around the hub, a blocking plate is provided so as to face the hub and be concentrically arranged with a rotational axis of the air blowing fan, and the 1 st rib is provided from the blocking plate in the outer frame direction. In this case, the blocking plate covers the hub portion which is not favorable for air supply in the air supply fan, so that the reverse flow of the air supply fan is easy to prevent.

Technical solution 7 the fan protecting cover of the air supply device is the protecting cover of the technical solution 6, wherein the blocking plate is a circle with a diameter larger than the hub. In this case, in the blower fan, the blocking plate blocks the blade root portion that is likely to cause the backward flow, so the backward flow is less likely to occur.

The fan guard cover of air supply equipment according to claim 8 is the guard cover according to any one of claims 1 to 7, wherein the 1 st rib is curved in a trochoid shape. In this case, the 1 st rib is easily bent by the blast air flow.

The fan guard of the blower device according to claim 9 is the guard according to any one of claims 6 to 8, wherein the 2 nd rib is inclined only on the outer peripheral side and not on the inner edge side. In this case, the plurality of 2 nd ribs are inclined only at the outer peripheral side in order to facilitate the high-speed outward diffusion of the blast air flow, and the manufacturing of the mold for integrally molding the fan protection cover is facilitated.

A fan guard of an air blowing device according to claim 10 is the guard according to claim 9, wherein the 2 nd rib is inclined in an outer peripheral side region from 1/3 of a radial length of the fan blade. In this case, since the plurality of 2 nd ribs are inclined only on the outer peripheral side from 1/3 of the fan blade where the blowing air flow is easily diffused to the outside at a high speed, the manufacturing of the mold for integrally molding the fan protection cover is facilitated.

Claim 11 is the fan guard cover of air supply equipment according to claim 9, wherein the 2 nd rib is inclined in the outer peripheral side region from 1/2 of the outer diameter of the outer frame. In this case, since the plurality of 2 nd ribs are inclined only on the outer peripheral side from 1/2 of the outer diameter of the outer frame where the blowing air flow is easily diffused outward at a high speed, the mold for integrally molding the fan guard is easily manufactured.

Brief description of the drawings

Fig. 1 is a partially cut-away side view of an outdoor unit of an air conditioner according to a first embodiment of the present invention;

fig. 2 is an exploded perspective view of an upper portion of an outdoor unit, partially cut away;

fig. 3 is a plan view of the outdoor unit;

FIG. 4 is an enlarged perspective view of the fan guard;

FIG. 5 is an enlarged view of the V portion of FIG. 4;

fig. 6 is a perspective view of the thickened portion.

Detailed description of the preferred embodiments

In fig. 1 and 3, an outdoor unit (an example of a blower) 10 of an air conditioning apparatus according to a first embodiment of the present invention is of a top-blowing type that sucks in outside air from a side surface, exchanges heat between the sucked outside air and a refrigerant, and blows the sucked outside air upward. The outdoor unit 10 includes: a housing 11; a heat exchange unit 12 disposed in the casing 11; a control unit 13 disposed in the casing 11 opposite to the heat exchange unit 12; a blower fan 15 for sucking and sending out external air; a fan guard 18 according to the first embodiment of the present invention fitted into the casing 11; a compressor 19 for compressing the refrigerant.

The housing 11 is composed of a rectangular parallelepiped housing body 16 having an upper opening, and an upper cover member 17 placed on an opening of the housing body 16. The casing body 16 is a thin metal plate member formed by sheet metal working, and has side walls 20a facing the control portion 13 and partial side walls 20b on both sides thereof, provided with outside air introduction ports 21a and 21b each formed of a plurality of rectangular openings, and a space 22 is formed inside thereof.

The upper cover member 17 is an integrally molded member made of synthetic resin, and has a substantially cylindrical shape, and is provided with a bell mouth 14 whose upper and lower portions are open. The upper cover member 17 is provided with: a placement portion 17a having a rectangular outer shape and placed on the housing body 16; an intermediate portion 17b which is contracted from the mounting portion 17a into a cylindrical shape and provided with a bell mouth 14; a circular boot mounting portion 17c that expands from the intermediate portion 17 b.

The blower fan 15 is a helical fan, is provided with a cylindrical hub 15a located at the center and a plurality of blades 15 provided around the hub, and is disposed inside the bell mouth 14. The blower fan 15 is rotated by a motor 31 fixed to the casing body 16.

The fan protection cover 18 is provided with: a centrally located occlusion plate 25; an outer frame 26 positioned on the outer peripheral side; a plurality of curved radiation ribs (one of the 1 st ribs) 27 connecting the closing plate 25 and the outer frame 26; an annular rib (one type of 2 nd rib) 28 is disposed annularly between the closing plate 25 and the outer frame 26. The fan guard 18 is made of synthetic resin that is integrally molded. The blocking plate 25 is a circular portion having a diameter larger than the hub 15a of the blower fan 15. The outer frame 26 is a sleeve portion having a diameter larger than the blades 15b of the blower fan 15. The outer frame 26 is fitted into the shroud attachment portion 17c, and the fan shroud 18 is fitted into the upper cover member 17.

The radial ribs 27 are radially arranged from the blocking plate 25 to the radially outer side in the direction of the outer frame 26, and are curved to protrude toward the downstream side in the rotation direction of the blower fan 15. Thus, the radial ribs 27 are easily aligned with the blowing air flow of the blowing fan 15 which is radially diffused and blown out. Specifically, the radial ribs 27 are projected and curved into a trochoid toward the downstream side in the rotational direction.

As shown in fig. 4, the radiation ribs 27 are inclined toward the downstream side in the rotation direction of the blower fan 15 along the flow of the blower fan 15. Specifically, the 1 st reference plane PL1 parallel to the rotation axis of the blower fan 15 is inclined to the downstream side in the rotation direction at the 1 st angle α on the air blowing side. The 1 st angle α is in the range of 20 to 40 degrees, preferably a value around 30 degrees. The 1 st angle α can be close to the delivery angle of the blowing air flow of the blowing fan 15 at the radial position where the axial velocity of the blowing air flow is maximum within the above range, and the blockage of the blowing air flow can be further effectively reduced.

The annular ribs 28 are annularly concentrically arranged at a predetermined interval in the radial direction around the rotation axis of the blower fan 15 between the closing plate 25 and the outer frame 26. As shown in fig. 1 and 3, of the annular ribs 28, the ribs arranged on the outer circumferential side of the diameter D/2 half the outer diameter D of the outer frame 256 are inclined radially outward along the flow of the blower fan 15. Specifically, the annular rib 28 faces a cylindrical 2 nd reference plane PL2 concentric with the rotation axis of the blower fan 15, and the air blowing side is inclined outward at the 2 nd angle β. The 2 nd angle β is in the range of 5 to 15 degrees, preferably a value around 10 degrees. By inclining the annular rib 28 on the outer peripheral side of the blower fan 15, which has a high flow velocity of the blower airflow and is easily diffused to the outside, the obstruction of the blower airflow can be effectively reduced, and the fan can be manufactured more easily than when it is inclined in its entirety.

A undercut portion UC is formed at the intersection of the radial rib 27 and the annular rib 28, which cannot be removed when the rib is integrally molded. Here, as shown in fig. 5, the undercut portion UC is an intersection portion where the die-stripping is impossible due to the mutually reverse inclination when stripping from the air blowing side and the suction side (vertical direction in fig. 5). Therefore, the undercut portion UC is provided with a thickened portion 29. As shown in fig. 6, the thickened portion 29 is a 4-sided body composed of 2 kinds of right-angled triangles having the 1 st angle α and the 2 nd angle β, respectively. The thickened portion 29 is provided at 2 undercut portions UC of the intersection portion. If the thickened portion 29 is provided, the undercut portion UC can be formed without using a separate die, so that the integral molding is easy, and at the same time, the strength of both end portions of the annular rib 28 subjected to the maximum bending moment is increased by the thickened portion 29, and the rigidity of the annular rib 28 is also enhanced. This also improves the rigidity of the fan guard 18 in the thickness direction as a whole.

The heat exchanger 12 is provided with a plurality of fins, and is disposed on side walls 20a and 20b having outside air inlets 21a and 21b in the casing 11, and the refrigerant exchanges heat with the introduced air through the inside thereof. For example: during cooling, the refrigerant condensed in the indoor unit exchanges heat with the introduced air to cool the air. During heating, the introduced air exchanges heat with the compressed high-temperature and high-pressure refrigerant, thereby heating the air.

The controller 13 controls the compressor 19 and the blower fan 15 of the outdoor unit 10 according to the room temperature and the operation mode.

The compressor 19 compresses a refrigerant to a high temperature and a high pressure, and switches between a heat exchanger (not shown) of an indoor unit and the heat exchange unit 12 to send the refrigerant during cooling and heating.

In the outdoor unit 10 having such a configuration, if the blower fan 15 is rotated, air passes through the outside air introduction ports 21a and 21b and is introduced into the casing 1 through the heat exchanger 12. And the introduced air is blown to the outside through the fan protecting cover 18 by the blowing fan 15.

At this time, even when the fan passes through the fan guard 18, the blocking plate 25 is larger than the hub 15a of the blower fan 15, and therefore, the backflow phenomenon that tends to occur near the root of the blade 15b can be reliably prevented. The radial ribs 27 are bent in the rotational direction along the rotational diffusion air flow of the blower fan 15 and inclined toward the downstream side in the rotational direction, and the annular ribs 28 are also inclined toward the radially outer side in accordance with the diffusion air flow, so that the air flow to be sent does not collide with the 2 kinds of ribs 27, 28, and pressure loss and noise can be suppressed.

Since the annular rib 28 is inclined radially outward, the rigidity of the fan guard 18 in the thickness direction is improved when the width of the annular rib 28 (the length in the direction intersecting the thickness of the annular rib 28) is larger than when the annular rib is not inclined. Further, since the thickened portion 29 is provided at the undercut portion UC at the intersection of the radial rib 27 and the annular rib 28, the strength of both end portions of the annular rib 28, which receive the maximum bending moment, is further increased by the thickened portion 29, and the rigidity of the annular rib 28 in the thickness direction as a whole is further increased.

Other embodiments

(a) In the above embodiment, the radial rib 27 is inclined toward the downstream side in the rotation direction, but the annular rib 28 may be inclined only toward the radially outer side, and the radial rib 27 may not be inclined.

(b) In the above embodiment, the undercut portion UC is provided with the thickened portion 29, and the fan guard 18 can be integrally formed only by the upper and lower molds without using a split mold. But the undercut portion UC may also be formed using a split die. However, in this case, since the undercut portion is large, the manufacturing cost is increased, and the rigidity cannot be enhanced by the thickened portion.

(c) In the above embodiment, the outer circumferential annular rib 28 is inclined radially outward from the outer frame outer diameter D1/2, but the entire annular rib 28 may be inclined, or the outer circumferential side may be inclined by a predetermined ratio (e.g., 1/3) from the radial length of the blades of the blower fan 15.

(d) In the above embodiment, the blowing fan 15 protected by the fan protection cover 18 is a spiral fan, and any form may be adopted if it is an axial flow fan. An outdoor unit of an air conditioner is exemplified as the air blowing device, but the air blowing device to which the fan protection cover is attached is not limited to an outdoor unit.

In claim 1, the 1 st rib is curved in the rotational direction, and therefore, since the sent air flow is curved in the rotational diffusion, the blown air flow does not collide with the 1 st rib, and the blocking of the blown air flow is easily reduced. The 2 nd rib is inclined toward the radial outside along the blowing air flow, so that the blowing air flow does not collide with the 2 nd rib, and the blocking of the blowing air flow by the 2 nd rib can be reduced. Therefore, even if the 1 st and 2 nd ribs are attached, the blowing air can be smoothly blown out, and the pressure loss and the noise can be reduced. Further, since the 2 nd rib is inclined along the blown air flow, the width of the 2 nd rib (the length in the direction intersecting the thickness direction of the 2 nd rib) is longer than that of the non-inclined rib, and the rigidity of the fan guard in the thickness direction can be improved.

In claim 2, since the 1 st rib is inclined along the blowing air flow like the 2 nd rib, the obstruction of the blowing air flow is further reduced, and the pressure loss and the noise can be reduced.

In claim 3, both the 1 st and 2 nd ribs are inclined outward, and even if a deep cut portion is generated, the deep cut portion can be eliminated by the thickened portion. Therefore, the mold can be easily removed, and the fan protection cover can be easily integrally formed of synthetic resin or the like. The sectional area of the fixing portion of the 2 nd rib having the largest bending moment is increased by the thickened portion, so that the rigidity of the 2 nd rib is further enhanced, and the rigidity of the fan guard in the thickness direction can be further improved.

In claim 4, the inclination angle of the 1 st rib is most suitable for the sending out of the rotary blowing air flow.

In claim 5, the inclination angle of the 2 nd rib is most suitable for the sending out of the rotation blowing air flow.

In claim 6, since the portion of the blower fan that is not conducive to air blowing is covered with the blocking plate, the blower fan can be prevented from flowing backward.

In claim 7, in the blower fan, the blade root portion at which the reverse flow is likely to occur is blocked by the blocking plate, so that the reverse flow is less likely to occur.

In the technical aspect 8, the 1 st rib is more likely to be bent along the blowing air flow.

In claim 9, since only the outer peripheral side of the plurality of 2 nd ribs is inclined and the blowing air flow is easily diffused to the outside at a high speed, the manufacturing of the fan shroud integrated molding die is also facilitated.

In claim 10, since the plurality of 2 nd ribs are inclined only on the outer peripheral side from the blower fan blades 1/3, the blown air flow is easily diffused to the outside at a high speed, and therefore, the manufacturing of the fan protection cover integral molding die is also facilitated.

In claim 11, since only the outer circumferential side of the plurality of 2 nd ribs is inclined from 1/2 of the outer diameter of the outer frame, the blown air flow is easily diffused to the outside at a high speed, and therefore, the manufacturing of the fan shroud integrated molding die is also facilitated.

Claims (11)

1. A fan protection cover (18) of an air supply device (10), the air supply device (10) being mounted to an air outlet (17) of the air supply device (10) having an air supply fan (15), the fan protection cover comprising: an outer frame (26) disposed on the outer periphery of the air outlet (17); a plurality of 1 st ribs (27) radially bent toward the outer frame (26) from the vicinity of the center of the outer frame (26) to the outside in the radial direction in the rotational direction of the blower fan (15); and a plurality of 2 nd ribs (28) which are integrally formed with the 1 st rib (27), are concentrically arranged in a ring shape at a predetermined interval in the radial direction around the rotation axis of the blowing fan (15), and are inclined outward in the radial direction at least along the blowing airflow of the blowing fan (15).

2. The fan protection cover (18) of the air blowing device (10) according to claim 1, wherein the 1 st rib (27) is inclined toward a rotation direction downstream side along a blowing air flow of the air blowing fan (15).

3. The fan protection cover (18) of an air supply apparatus (10) according to claim 2, wherein the 1 st rib (27) and the 2 nd rib (28) are inclined at different angles, and a thickened portion (29) is provided between the 1 st rib (27) and the 2 nd rib (28) at the intersection of the two ribs.

4. The fan guard (18) of the blower (10) according to claim 2 or 3, wherein the 1 st rib (27) is inclined 20 to 40 degrees toward the downstream side in the rotational direction with respect to a 1 st reference plane (PL1) parallel to the rotational axis of the blower fan (15).

5. The fan guard (18) of the blower (10) according to claim 4, wherein the 2 nd rib (28) is inclined 5 to 15 degrees to the outside of the blower side with respect to a cylindrical 2 nd reference surface (PL2) concentric with the rotational axis of the blower fan (15).

6. The fan guard (18) of the air supply apparatus (10) according to claim 1 or 2, wherein the air supply fan (15) is a helical fan constituted by a cylindrical hub (15a) located at the center and a plurality of blades (15b) provided around the hub (15 a); a blocking plate (25) which is opposite to the hub (15a) and is arranged coaxially with the rotating shaft core of the air supply fan (15) is also arranged; the 1 st rib (27) faces the outer frame (26) from the blocking plate (25).

7. The fan guard (18) of the air supply apparatus (10) according to claim 6, wherein the blocking plate (25) is circular with a diameter larger than the hub (15 a).

8. The fan guard (18) of an air supply apparatus (10) of claim 1 or 2, wherein the 1 st rib (27) is curved in a trochoid shape.

9. The fan guard (18) of the air supply equipment (10) of claim 6, wherein the 2 nd rib (28) is inclined only on the outer peripheral side and not inclined on the inner edge side.

10. The fan protection cover (18) of the air blowing device (10) according to claim 9, wherein the 2 nd rib (28) is inclined in an outer peripheral side region from 1/3 of a radial length of the blade (15b) of the air blowing fan (15).

11. The fan guard (18) of the air blowing device (10) of claim 9, wherein the 2 nd rib (28) is inclined in an outer peripheral side region from 1/2 of an outer diameter of the outer frame (26).