JP2021014794A - Turbo fan - Google Patents

Abstract

To provide a turbo fan that can suppress noise from a junction part between a blade member and a shroud even when the blade member is twisted by the centrifugal force at rotation.SOLUTION: A turbo fan includes a welding hole 71 in a welding locking part 70 of a shroud 26. When a welding pin 47 is inserted into the hole, a blade member 27 is fixed by the melt welding pin 47 while blocking a cutout part 90 formed in an inner peripheral edge part 71a of the welding hole 71.SELECTED DRAWING: Figure 9

Description

The present invention relates to a turbofan, and more particularly to a turbofan capable of stably supporting a blade member and making it possible that the shroud and the blade member are less likely to be displaced even when the blade member is distorted in the centrifugal direction.

Conventionally, a turbofan which is mounted on an indoor unit of an air conditioner and is composed of a main plate, a shroud, and a plurality of wings has been known.

As such a turbo fan, conventionally, for example, a main plate having a boss fixed to a rotating shaft of a motor in the center, a shroud forming a suction air guide wall, and a plurality of blade members are separately molded with a thermoplastic resin. , The main plate has a fitting portion with a plurality of blade members, the shroud has a fitting portion with a plurality of blade members, and a plurality of blade members are attached to a plurality of fitting portions of the main plate and the shroud. There is disclosed a technique of fitting in parallel with each other and integrating them by ultrasonic welding (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-206804

However, in the technique of Patent Document 1, the blade member is integrated by ultrasonic welding in a state where the blade member is fitted to the fitting portion formed on the main plate, and the blade member is integrated by centrifugal force during rotation. There is a risk that abnormal noise is likely to occur when the number of revolutions changes due to twisting.

In particular, in recent turbofans, in order to secure the air volume, the blade members tend to be curved and arranged at an angle with respect to the main plate, and the blade members tend to be twisted when the turbofan rotates, especially with a shroud. There is a problem that abnormal noise is generated from the welded portion of the joint portion with the blade member.

The present invention has been made in view of the above points, and an object of the present invention is to provide a turbofan capable of stably supporting a blade member and suppressing abnormal noise at a joint portion of the blade member. To do.

In order to achieve the above object, the present invention is a turbo fan provided with a main plate, a shroud, and a plurality of blade members between the main plate and the shroud, wherein the blade members include a welding support portion and the welding is performed. A welding pin is projected from the support portion, a welding engagement portion with which the welding support portion is engaged is formed and a welding hole is formed on the shroud, and the welding pin is cross-sectionald with the welding pin. It is characterized in that it is inserted into the welding hole having a different shape, the welding pin is melted, and the blade member and the shroud are joined to cover the welding hole.

Further, in the above configuration, a notch is formed in the welding hole.

Further, in the above configuration, a welding guide seat portion is formed around the welding hole of the welding engagement portion.

Further, in the above configuration, the blade member includes a flange portion, and the flange portion is integrally molded with the main plate so that the blade member and the main plate are joined to each other.

Further, in the above configuration, the blade member is formed by contacting the peripheral edges of two resin blade members, and the blade member is composed of a member having a friction coefficient smaller than that of the shroud. It is characterized by.

Further, in the above configuration, the blade member is formed by combining a resin-made positive pressure side blade member and a negative pressure side blade member, and at least one of them is a resin member containing a material having a small friction coefficient. It is characterized by being formed.

According to the present invention, the welding pin is inserted into a welding hole having a cross-sectional shape different from that of the welding pin, and the welding pin is melted to cover the welding hole and join the blade member and the shroud. Twisting of the joint during rotation can be reduced, and abnormal noise can be suppressed.

It is a vertical sectional view which shows the embodiment of the ceiling-embedded air conditioner to which the turbofan of this invention is applied. It is a perspective view of the ceiling-embedded air conditioner of this embodiment. It is a bottom view of a turbofan. It is a perspective view of a turbofan. It is an exploded perspective view of a turbofan. It is a plan view of a shroud. FIG. 6 is a sectional view taken along the line AA of FIG. It is the B part enlarged view of FIG. Enlarged view of the main part of FIG.

Hereinafter, embodiments of the turbofan according to the present invention will be described with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing an embodiment of a ceiling-embedded air conditioner to which a turbofan according to the present invention is applied. FIG. 2 is a perspective view of a ceiling-embedded air conditioner.

In the present embodiment, as shown in FIG. 1, the indoor unit 10 is installed in the ceiling space 13 between the ceiling 11 of the building and the ceiling plate 12 installed below the ceiling 11.

As shown in FIG. 1, the indoor unit 10 includes a box-shaped air conditioner main body 14 having an open lower surface, and a hanging metal fitting 18 is attached to an outer corner of the air conditioner main body 14. Is installed. The air conditioner main body 14 is installed in a state of being suspended from the ceiling 11 by a suspension bolt 15 connected to the suspension metal fitting 18. Inside the air conditioner main body 14, a styrofoam heat insulating member 16 is arranged in contact with the inner surface of the side plate 17 of the air conditioner main body 14 to prevent dew condensation on the side plate 17.

A fan motor 21 is attached to the lower surface of the upper plate of the air conditioner main body 14, so that the rotary shaft 22 that is rotationally driven by the drive of the fan motor 21 extends downward to the fan motor 21. It is provided. A turbofan 23 is attached to the lower end portion of the rotating shaft 22, and the fan motor 21 and the turbofan 23 constitute a blower device 20.

The turbofan 23 includes a main plate 24 formed in an annular plate shape. An inverted truncated cone-shaped motor accommodating portion 25 extending downward is formed in the central portion of the main plate 24.

The fan motor 21 is housed in the motor housing part 25, and the rotating shaft 22 of the fan motor 21 extends downward and is connected to the bottom surface of the motor housing part 25. Then, by rotationally driving the fan motor 21, the turbofan 23 is configured to rotate via the rotary shaft 22.

A shroud 26 is provided below the main plate 24, and the shroud 26 is formed in an annular shape having an arc-shaped peripheral surface. Between the main plate 24 and the inner peripheral surface of the shroud 26, there are a plurality of blade members 27 arranged at predetermined intervals in the circumferential direction, and the blade members 27 are integrally molded with the main plate 24.

An orifice 28 is arranged below the shroud 26, and the orifice 28 is formed in an annular shape having an arc-shaped peripheral surface.

Between the blower 20 and the heat insulating member 16, a heat exchanger 30 formed in a substantially square shape in a plan view is arranged so as to surround the side of the blower 20.

The heat exchanger 30 is a heat exchanger 30 that functions as a refrigerant evaporator during the cooling operation and as a refrigerant condenser during the heating operation. The heat exchanger 30 exchanges heat between the indoor air sucked into the air conditioner main body 14 and the refrigerant, cools the air in the air conditioning room during the cooling operation, and heats the indoor air during the heating operation. It is configured to be able to.

Further, on the lower side of the heat exchanger 30, a drain pan 31 is arranged so as to correspond to the lower surface of the heat exchanger 30. The drain pan 31 is for receiving the drain water generated in the heat exchanger 30. Further, a suction port 32 of the blower 20 is formed in the central portion of the drain pan 31.

Further, as shown in FIGS. 1 and 2, a substantially square decorative panel 33 is attached to the lower surface of the air conditioner main body 14 so as to cover the lower opening of the air conditioner main body 14.

A suction port 34 communicating with the suction port 32 of the drain pan 31 is formed in the central portion of the decorative panel 33, and a suction grill 35 covering the suction port 34 can be attached to and detached from the suction port 34 portion of the decorative panel 33. It is attached. A filter 36 for removing dust and the like in the air is provided on the air conditioner main body 14 side of the suction grill 35.

An air outlet 37 for sending air after air conditioning into the room is formed at a position outside the suction port 34 of the decorative panel 33 and along each side of the decorative panel 33. Each outlet 37 is provided with a flap 38 for changing the wind direction. Then, the rotary shaft 22 is rotationally driven by the fan motor 21 to rotate the turbofan 23, so that the air in the room is sucked from the suction ports 32 and 34, passes through the filter 36, and then passes through the heat exchanger 30. The air is exchanged by heat, and the air after air conditioning is sent into the room from the air outlet 37.

Next, the turbo fan will be described in more detail.

FIG. 3 is a bottom view of the turbofan. FIG. 4 is a perspective view of the turbofan. FIG. 5 is an exploded perspective view of the turbofan.

In the turbofan 23, the shroud 26, the main plate 24, and the plurality of blade members 27 are integrally molded in advance, and after manufacturing each of these, they are assembled to form the turbofan 23.

In the present embodiment, as shown in FIG. 5, the blade member 27 includes a positive pressure side blade member 40 located on the positive pressure side and a negative pressure side blade member 41 located on the negative pressure side, and these two blade members are provided. A single blade member 27 is formed by being brought into contact with each other.

The positive pressure side blade member 40 includes a blade main body portion 42 forming a surface on the positive pressure side and a flange portion 43 extending the bottom plate of the blade main body portion 42, and the flange portion 43 is the bottom plate of the negative pressure side blade member 41. It is formed extending to the receiving side and the opposite side. Further, a mounting hole 44 is formed in the flange portion 43. A stepped welding support portion 46 formed at different heights is formed on the upper portion of the positive pressure side blade member 40. The upper surface of each step of the welding support portion 46 is a flat surface, and as shown in FIG. 5, a welding pin 47 is provided so as to project from each of the welding support portions 46.

The blade member 27 is integrally molded with the main plate 24 via the flange portion 43.

Further, the negative pressure side blade member 41 includes a blade main body portion 48 forming a surface on the negative pressure side. An engaging pin (not shown) is formed on the inner surface of the blade body 42 of the positive pressure side blade member 40, and the engaging pin is engaged with the inner surface of the blade body 48 of the negative pressure side blade member 41. A joint recess (not shown) is formed.

As shown in FIGS. 6 to 8, a welding engagement portion 70 to which the welding support portion 46 of the blade member 27 is engaged is formed on the inner surface of the shroud 26 so as to bulge outward from the shroud 26. ing. The inner surface shape of the welding engagement portion 70 is formed in substantially the same shape as the outer surface shape of the welding support portion 46, and the welding support portion 46 of the blade member 27 is engaged with the welding engagement portion 70. It is configured so that the blade member 27 and the shroud 26 can be stably supported.

Further, the welding engagement portion 70 is formed with a welding hole 71 through which the welding pin 47 is inserted. The inner peripheral edge portion 71a of the welding hole 71 has a substantially circular shape, and is formed at a position away from the outer peripheral portion of the welding and welding pin 47 into which a part of the edge portion of the inner peripheral edge portion 71a is inserted, and is welded. A plurality of rectangular notches 90 are formed between the pin 47 and the pin 47.

Then, the welding pin 47 is melted by heat welding, and the melted welding pin 47 closes the inside of the notch 90 to fix the blade member 27 and the shroud 26.

In the present embodiment, heat welding is used as the welding means, but the same effect can be obtained by other welding means such as impulse welding (heater welding), infrared heater welding, and ultrasonic welding.

Further, by engaging the engaging protrusion of the negative pressure side blade member 41 with the engaging portion of the positive pressure side blade member 40 and engaging the engaging pin (not shown) with the engaging recess, the positive pressure side blade member 40 The peripheral edge of the blade member 41 is brought into contact with the peripheral edge of the negative pressure side blade member 41 to form the blade member 27.

Subsequently, the blade member 27 is incorporated into a molding jig for molding the main plate 24 and integrally molded by insert molding.

Since the main plate 24 and the blade member 27 are integrally molded in this way, the joint portion between the main plate 24 and the blade member 27 does not shift due to distortion in the centrifugal direction, so that abnormal noise can be prevented.

Next, the welding support portion 46 of the blade member 27 is engaged with the welding engagement portion 70 of the shroud 26, and the welding pin 47 of the blade member 27 is projected from the welding hole 71 of the shroud 26.

In this state, heat is applied to the welding pin 47 for heat welding to melt the welding pin 47, and the melted welding pin 47 closes the inside of the notch 90, whereby the blade member 27 and the shroud 26 are formed. And fix.

At this time, the blade member 27 and the shroud 26 can be stably supported in a state where the welding support portion 46 of the blade member 27 is engaged with the welding engagement portion 70, and the welding work can be easily performed. Is possible.

As described above, in the present embodiment, the blade member 27 is incorporated into the molding jig for molding the main plate 24 and integrally molded by insert molding, so that the flange portion 43 formed on the positive pressure side blade member 40 is formed. It is joined to the main plate 24.

Further, in the present embodiment, the blade member 27 is in contact with and welded to the welding engagement portion 70 of the shroud 26, and the resin blade member 27 has a smaller friction coefficient than the resin shroud 26. Since the blade member 27 is composed of members, the shroud 26 is twisted by centrifugal force when the blade member 27 is rotated, and even if the blade member 27 is displaced from the shroud 26, an abnormal noise such as a creaking noise due to frictional vibration is generated. It can be suppressed.

Further, at least one of the positive pressure side blade member 40 and the negative pressure side blade member 41 constituting the blade member 27 is a resin member containing a material having a small friction coefficient.

As a result, even if twisting occurs due to the centrifugal force of the blade member 27, the peripheral edge portion of the negative pressure side blade member 41 rubs against the positive pressure side blade member 40, and abnormal noise such as creaking noise due to frictional vibration can be suppressed. ..

Although it is assumed that a plurality of notches 90 are provided, if the blade member 27 is twisted by centrifugal force and no creaking noise is generated at the joint with the shroud 26, the number of notches may be one. ..

Although the embodiments of the present invention have been described with reference to the drawings, the present invention is not limited to the above embodiments and can be modified without departing from the gist of the invention.

10 Indoor unit 14 Air conditioner body 24 Main plate 23 Turbo fan 26 Shroud 27 Blade member 40 Positive pressure side blade member 41 Negative pressure side blade member 42, 48 Blade body 43 Flange 44 Mounting hole 46 Welding support 47 Welding pin 70 Welding engagement part 71 Welding hole 71a Inner peripheral edge 90 Notch

Claims (6)

In a turbo fan provided with a main plate, a shroud, and a plurality of blade members between the main plate and the shroud, the blade member includes a welding support portion, and a welding pin is projected from the welding support portion. , The welding support portion is engaged with the shroud to form a welding engagement portion and a welding hole is formed, and the welding pin is inserted into the welding hole having a cross-sectional shape different from that of the welding pin. , A turbo fan characterized in that the welding pin is melted to cover the welding hole and the blade member and the shroud are joined. The turbofan according to claim 1, wherein a notch is formed in the welding hole. The turbofan according to claim 1 or 2, wherein a welding guide seat portion is formed around the welding hole of the welding engagement portion. The turbo according to any one of claims 1 to 3, wherein the blade member includes a flange portion, and the flange portion is integrally molded with the main plate to join the blade member and the main plate. fan. The claim is characterized in that the blade member is formed by bringing the peripheral edges of two resin blade members into contact with each other, and the blade member is composed of a member having a friction coefficient smaller than that of the shroud. The turbofan according to any one of 1 to 4. The blade member is formed by combining a resin-made positive pressure side blade member and a negative pressure side blade member, and at least one of them is made of a resin member containing a material having a small friction coefficient. The turbofan according to any one of claims 1 to 5.

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