JP7394282B2 - turbo fan - Google Patents

Description

The present invention relates to a turbo fan, and more particularly to a turbo fan that can stably support a blade member and prevents misalignment between a shroud and the blade member even when the blade member is distorted in the centrifugal direction.

2. Description of the Related Art Turbo fans have been known that are installed in indoor units of air conditioners, etc., and are composed of a main plate, a shroud, and a plurality of blades.

Conventionally, for such a turbofan, for example, a main plate having a boss fixed to the rotating shaft of the motor in the center, a shroud forming a suction air guide wall, and a plurality of blade members are separately molded from thermoplastic resin. , the main plate has a fitting part with the plurality of blade members, the shroud has a fitting part with the plurality of blade members, and the plurality of blade members are connected to the rotation axis at the plurality of fitting parts of the main plate and the shroud. A technique has been disclosed in which the parts are fitted in parallel to each other and integrated by ultrasonic welding (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2014-206084

However, in the technique of Patent Document 1, the blade members are fitted into the fitting portion formed on the main plate and are integrated by ultrasonic welding, and the blade members are caused by centrifugal force during rotation. There is a risk that it may become twisted and cause abnormal noise when the rotation speed changes.

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

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a turbo fan that can stably support blade members and suppress abnormal noises at the joints of the blade members. do.

To achieve the above object, the present invention provides a turbo fan including a main plate, a shroud, and a plurality of blade members between the main plate and the shroud, wherein the blade member includes a welding support portion, and the welding A welding pin is provided protrudingly on the support part, a welding engagement part is formed in the shroud in which the welding support part is engaged, and a welding hole is formed, and the welding pin has a cross section with the welding pin. The blade member is inserted into the welding holes having different shapes, the welding pin is melted, and the blade member and the shroud are joined by covering the welding hole.

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

Moreover, in the said structure, the welding guide seat part is formed around the said welding hole of the said welding engaging part, It is characterized by the above-mentioned.

Moreover, in the said structure, the said blade|wing member is equipped with a flange part, and the said flange part is integrally molded with the said main plate, and the said blade|wing member and the said main plate are joined.

Further, in the above configuration, 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 made of a member having a smaller coefficient of friction than the shroud. It is characterized by

Further, in the above configuration, the blade member is formed by combining a positive pressure side blade member and a negative pressure side blade member made of resin, and at least one of the blade members is made of a resin member containing a material with a small coefficient of friction. It is characterized by the fact that it has been formed.

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

1 is a longitudinal cross-sectional view showing an embodiment of a ceiling-embedded air conditioner to which a turbo fan of the present invention is applied. FIG. 1 is a perspective view of a ceiling-embedded air conditioner according to the present embodiment. FIG. 3 is a bottom view of the turbo fan. FIG. 2 is a perspective view of a turbo fan. FIG. 2 is an exploded perspective view of a turbo fan. FIG. 3 is a plan view of the shroud. 7 is a sectional view taken along line AA in FIG. 6. FIG. 7 is an enlarged view of part B in FIG. 6. FIG. Enlarged view of main parts of Figure 8

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

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

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

As shown in FIG. 1, this indoor unit 10 includes an air conditioner main body 14 formed in a box shape with an open bottom surface. is installed. The air conditioner main body 14 is installed in a suspended state from the ceiling 11 by a hanging bolt 15 connected to a hanging fitting 18. A heat insulating member 16 made of polystyrene foam is placed inside the air conditioner main body 14 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, and a rotating shaft 22 that is rotationally driven by the fan motor 21 extends downward. It is provided. A turbo fan 23 is attached to the lower end portion of the rotating shaft 22, and the fan motor 21 and the turbo fan 23 constitute a blower device 20.

The turbo fan 23 includes a main plate 24 formed in an annular plate shape. A motor accommodating portion 25 in the shape of an inverted truncated cone is formed in the center of the main plate 24 and extends downward.

A fan motor 21 is housed in the motor housing part 25 , and a rotating shaft 22 of the fan motor 21 extends downward and is connected to the bottom surface of the motor housing part 25 . By rotating the fan motor 21, the turbo fan 23 is rotated via the rotating shaft 22.

A shroud 26 is provided below the main plate 24, and the shroud 26 has an annular shape with an arcuate 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 with an arcuate peripheral surface.

A heat exchanger 30 is arranged between the blower device 20 and the heat insulating member 16 so as to surround the side of the blower device 20 and is bent into a substantially rectangular shape in a plan view.

The heat exchanger 30 functions as a refrigerant evaporator during cooling operation, and functions as a refrigerant condenser during heating operation. The heat exchanger 30 exchanges heat between the indoor air sucked into the air conditioner body 14 and the refrigerant, thereby cooling the air in the air conditioned room during cooling operation and heating the indoor air during heating operation. It is configured so that it can be done.

Further, a drain pan 31 is arranged below the heat exchanger 30 so as to correspond to the lower surface of the heat exchanger 30. This drain pan 31 is for receiving drain water generated by the heat exchanger 30. Furthermore, a suction port 32 of the blower device 20 is formed in the center of the drain pan 31 .

Further, as shown in FIGS. 1 and 2, a substantially rectangular 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 that communicates with the suction port 32 of the drain pan 31 is formed in the center portion of the decorative panel 33, and a suction grill 35 that covers the suction port 34 is removably attached to the suction port 34 portion of the decorative panel 33. installed. A filter 36 is provided on the side of the air conditioner main body 14 of the suction grill 35 to remove dust and the like from the air.

Air outlets 37 are formed outside the inlet 34 of the decorative panel 33 and along each side of the decorative panel 33 to send air after conditioning into the room. Each outlet 37 is provided with a flap 38 for changing the wind direction. Then, by rotationally driving the rotary shaft 22 by the fan motor 21 and rotating the turbo fan 23, indoor air is sucked in through the suction ports 32 and 34, passes through the filter 36, and then passes through the heat exchanger 30. The air conditioner is configured such that the air is exchanged with heat, and the air after conditioning is sent into the room from the outlet 37.

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

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

In the turbo fan 23, a shroud 26, a main plate 24, and a plurality of blade members 27 are integrally molded in advance, and after these are manufactured, they are assembled to form the turbo fan 23.

In this 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. They are brought into contact to form one blade member 27.

The positive pressure side blade member 40 includes a blade root body portion 42 constituting a positive pressure side surface, and a flange portion 43 extending from the bottom plate of the blade root body portion 42, and the flange portion 43 is connected to the bottom plate of the negative pressure side blade member 41. It is formed to extend on the receiving side and the opposite side. Furthermore, a mounting hole 44 is formed in the flange portion 43 . At the upper part of the positive pressure side blade member 40, step-shaped welded support parts 46 are formed at different heights. The upper surface of each stage of the welding support portions 46 is a flat surface, and a welding pin 47 is provided protruding from each of these welding support portions 46, as shown in FIG.

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

Further, the negative pressure side blade member 41 includes a blade root body portion 48 that constitutes a negative pressure side surface. An engagement pin (not shown) is formed on the inner surface of the blade body part 42 of the positive pressure side blade member 40, and an engagement pin (not shown) is formed on the inner surface of the blade body part 48 of the negative pressure side blade member 41. A matching recess (not shown) is formed.

As shown in FIGS. 6 to 8, on the inner surface of the shroud 26, a welding engagement part 70 with which the welding support part 46 of the blade member 27 is engaged is formed so as to bulge out to the outside of the shroud 26. ing. The inner surface shape of the welding engagement part 70 is formed almost the same as the outer shape of the welding support part 46, and when the welding support part 46 of the blade member 27 is engaged with the welding engagement part 70, The blade member 27 and the shroud 26 are configured to be stably supported.

Further, the welding engagement portion 70 is formed with a welding hole 71 into which the welding pin 47 is inserted. The inner circumferential edge 71a of the welding hole 71 has a substantially circular shape, and is formed so as to be located in a direction away from the outer circumference of the welding pin 47 through which a part of the edge of the inner circumferential edge 71a is inserted. A plurality of rectangular notches 90 are formed between the pin 47 and the pin 47 .

Then, the blade member 27 and the shroud 26 are fixed by melting the welding pin 47 by heat welding and closing the inside of the notch 90 with the melted welding pin 47.

In this embodiment, thermal welding is used as the welding means, but similar effects can be obtained by other welding means such as impulse welding (heater welding), infrared heater welding, and ultrasonic welding.

In addition, by engaging the engagement protrusion of the negative pressure side blade member 41 with the engagement portion of the positive pressure side blade member 40 and engaging the engagement pin (not shown) with the engagement recess, the positive pressure side blade member 40 The blade member 27 is formed by bringing the peripheral edge of the negative pressure side blade member 41 into contact with the peripheral edge of the negative pressure side blade member 41 .

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 manner, there is no displacement due to strain in the centrifugal direction at the joint between the main plate 24 and the blade member 27, so abnormal noise can be prevented.

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

In this state, by applying heat to the welding pin 47 and thermally welding it, the welding pin 47 is melted, and the melted welding pin 47 closes the inside of the notch 90, thereby closing the blade member 27 and the shroud 26. and fix it.

At this time, with the welding support part 46 of the blade member 27 engaged with the welding engagement part 70, the blade member 27 and the shroud 26 can be stably supported, and the welding work can be easily performed. becomes possible.

As described above, in this embodiment, the blade member 27 is incorporated into a 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 It is joined to the main plate 24.

Further, in this 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 coefficient of friction than the resin shroud 26. By being composed of members, even if the shroud 26 is twisted due to centrifugal force when the blade member 27 rotates, and the blade member 27 is displaced from the shroud 26, abnormal noises such as squeaks due to frictional vibrations will not be generated. Can be suppressed.

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

As a result, even if twisting occurs due to the centrifugal force of the blade member 27, the peripheral edge of the negative pressure side blade member 41 rubs against the positive pressure side blade member 40, making it possible to suppress abnormal noises such as squeaks due to frictional vibrations. .

Although it is assumed that a plurality of notches 90 are provided, the number of notches may be one as long as the blade member 27 is twisted by centrifugal force and does not generate a squeaking sound at the joint with the shroud 26. .

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

10 Indoor unit 14 Air conditioner main 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 base body portion 43 Flange portion 44 Mounting hole 46 Welding support portion 47 Welding pin 70 Welding engagement part 71 Welding hole 71a Inner peripheral edge part 90 Notch part

Claims (1)

In a turbo fan comprising 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 protrudes from the welding support portion. , forming a welding engagement part in the shroud with which the welding support part is engaged, and also forming a welding hole, and inserting the welding pin into the welding hole having a different cross-sectional shape from the welding pin. , the blade member and the shroud are joined by melting the welding pin to cover the welding hole ;
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 made of a member having a smaller coefficient of friction than the shroud.
A turbo fan characterized by:

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