ES2232339T3 - FAN ROTOR, METHOD FOR MANUFACTURING AND FAN. - Google Patents

Abstract

Rotor used in a fan, comprising: a hub (5) and a blade (6), wherein said blade includes a multi-layer part (7, 8), characterized in that said multi-layer part includes a rigid layer only on an air receiving surface in the intrados (15) of said blade (6) and includes a molded foam layer (8) adhered to said rigid layer in the extrados (16).

Description

Rotor for fan, method for manufacturing and fan

Technical Field of the Invention

The present invention relates to a fan and, more particularly, to a rotor used in the fan, as well as a method for manufacturing the rotor.

Background of the invention

So far, the rotor used in the fan It was manufactured by stamping a metal. In particular, recently, the rotor used in the fan was manufactured by molding a resin. Rotors made of resin They have been widely used. These rotors are given to know in documents GB-A-2 279 114 and US-A-3 647 317. In order to improve the performance of this type of fan, the profile Aerodynamic rotor blades are designed in accordance with the blade theory. The rotor that has a shape is proposed designed with blade theory. For example, the rotor used in The outdoor unit of a home air conditioner has a diameter of 300 mm and the maximum wall thickness of the blades is 15 mm

However, if the rotor with such thickness is manufactures by surface injection molding of a resin of the blade may have roughness due to contraction or resin warping due to thermal contraction. If the rotor provided with such blades with roughness is used in the apparatus air conditioner, disturbances occur in laminar flow at shovel surface length and noise increases. For other part, to avoid such contraction or warping, it is tried to take perform a gradual cooling, extending the cooling time by injection molding. In such a method, however, the time of molding cycle is longer, which lowers the productivity.

More recently, the method of gas injection molding and the multi-layer molding method of two stages The gas injection molding method of the rotor comprises a resin injection stage in the mold cavity and a stage of formation of a hollow part inside a plurality of blades injecting inert gas, such as nitrogen compressed, in the cavity. The multilayer rotor molding method It consists of a rotor molding process that is divided into two stages

However, since the rotor is a body rotating, the plurality of blades must be balanced. At gas injection molding method, however, it is difficult get the blade wall thickness to be exactly the specified. That is, the hollow part of the shovel cannot controlled due to the correlation between the gas pressure and the resin colability. Therefore, it is difficult to obtain balanced sets of blades. In the molding method with gas injection therefore cannot be expected the same level of perfection that is obtained with the molding method by injection. In the general multilayer molding method, however, only an element of medium thickness can be molded. In order for the device high performance air conditioner, a large rotor is required diameter. Therefore, if a large diameter rotor is molded with the multilayer molding method, the maximum thickness of the thick part is thicker. Consequently, the weight of the rotor increases and so both increase the starting torque and other loads that the motor that drives the rotor.

It is, therefore, an object of the invention present a lightweight rotor, high performance and manufactured with high productivity.

Summary of the invention

The rotor used in the fan of the invention comprises:

a bucket, and

a shovel protruding from the bucket,

in which the blade has multiple layers and at less one of the multiple layers has a foam layer molded

The method of manufacturing the rotor used in The fan of the invention comprises:

a first stage of molding a bucket and a first blade layer protruding from the bucket, and

a second stage of laminating a second layer of shovel that presents a layer of molded foam on the first shovel layer

The fan of the invention comprises:

a motor,

a hub connected to the engine, and

a shovel protruding from the bucket,

in which the blade has a rigid layer and a molded foam layer laminated to the rigid layer and

the blades rotate driven by the motor.

The outdoor unit of the air conditioner of the invention comprises:

a heat exchanger, and

a fan installed near the exchanger of heat,

in which the fan includes a motor, a hub connected to the engine and a blade protruding from the hub, and

The blade has a rigid layer and a layer of molded foam laminated in the rigid layer, and

the blades rotate driven by the motor.

With this constitution, a rotor with the wall thickness, light weight, large diameter and shape needed. How result, a rotor with an excellent performance of blown. What's more, you get a fan with an excellent blowing performance. In addition, an air conditioner is obtained With excellent heat exchange function.

Brief description of the drawings

Figure 1 is a perspective view partial explosion of an outdoor unit of an appliance air conditioner equipped with a fan that uses a rotor according to an embodiment of the invention.

Figure 2 is a general perspective view of a fan rotor according to an embodiment of the invention.

Figure 3 is a sectional view along line 6A-6B of the rotor blades shown in the figure 2.

Numerical references

one

Body main outdoor unit

2

Rotor

3

Engine fan

4

Nut

5

Cube

6

Shovel

7

Cap rigid, first layer of shovel

8

Cap molded foam, second layer of shovel

10

Fan

12

Heat exchanger

fifteen

Intradós

16

Extradós

18

Cap Exterior

Detailed description of the invention

A fan rotor according to a form of embodiment of the invention includes a bucket and blades that have multiple layers, and at least one layer of multiple layers presents a molded foam layer, and at least one layer of the The rest of the layers have a rigid layer. Foam layer molded is a layer of a molded body that contains multiple pores, multiple foams or multiple hollow parts. The layer of molded foam is formed, for example, by molding a molding material containing a foaming agent or agent expansive. The rigid layer is a layer that has a stiffness with High mechanical resistance to withstand air pressure. The layer rigid is, for example, a body molded in plastic that does not It has cavities, a body molded in rigid plastic or a molded body with a reinforcing load. Such a rigid layer is manufactured, for example, by an injection molding method Ordinary.

With this constitution, a rotor with the wall thickness, light weight, large diameter and shape needed.

Preferably, the blade has two layers, and One of them is a molded foam layer. With this constitution, a rotor is obtained with the same performance as indicated previously.

Preferably, the molded foam layer is arranged in the extrados when turning. With this constitution, rigidity of the intrados is greater than that of the extrados. Accordingly when the rotor rotates at high speed, the air pressure is received in the rigid intrados, and this allows it to rotate at high speed. Be obtains excellent blowing performance even at high speed. In addition, the weight of the extrados is less. As a result, it You get, in general, a lightweight rotor.

Preferably, the thickness of the foam layer molded is larger than that of the other layers. With this constitution, a much lighter rotor is obtained.

A method of manufacturing the rotor according to a embodiment of the invention comprises a step of formation of a rigid layer by injection molding and a foaming and molding stage. With this constitution, the rotor can Complete in a continuous process.

Preferably, foaming and molding are run immediately after forming the rigid layer by injection molding.

Preferably, a first surface of the rigid layer has a surface roughness Ra of between 50 µm and 500 µm. Foaming and molding run on the side of the first surface, and thus adheres and provides a layer of foam molded Thus, since the first surface of the rigid layer It has adequate surface roughness, the foam layer Molded firmly adheres to the rigid layer. Consequently, it sufficiently maintains the strength of the bond between the layer of molded foam, provided with a thick part, and the rigid layer.

Preferably, the foaming factor of the layer Molded foam is between 1.5 and 4. With such foaming factor, a rotor is obtained that does not present problems in use practical.

The following describes in detail the Examples of embodiment of the invention with reference to attached drawings.

Execution Example one

Figure 1 is a perspective view exploded rotor used in a fan of an appliance air conditioner according to an exemplary embodiment of the invention. Figure 2 is a perspective view of the rotor according to an exemplary embodiment of the invention. Figure 3 is a sectional view along line 6A-6B of the rotor blades shown in figure 2.

In figure 1, a main body of a unit outside 1 of the air conditioner includes a fan 10 and a heat exchanger 12 arranged near the fan 10. The fan 10 is provided with a fan motor 3 and a rotor 2. The rotor 2 is fixed to the fan motor 3 by a screw and a nut 4. By turning the fan 10, the air will it drives from intrados 15 to extrados 16. By means of the driven air, The heat exchanger cools or heats.

In Figure 2, the rotor 2 is provided with a hub 5 and a plurality of blades 6 protruding from hub 5.

As shown in figure 3, the blade 6 is provided with a rigid layer 7, as the first blade layer, and a layer molded foam 8, as a second layer of shovel. In figure 3, when the rotor rotates, the blade 6 receives the air coming from the side of the rigid layer 7 and sends it in the direction of the side of the layer of molded foam 8. The blades 6 rotate centrifugally.

The cube 5 and the rigid layer 7 have been manufactured by injection molding, with an AES plastic material that Contains 20% by weight of fiberglass. AES is a copolymer of an acrylic compound, EPDM and styrene. EPDM is a terpolymer of ethylene and propylene. The molded body is provided with a hub 5 positioned in the center and three rigid layers 7 protruding from the cube 5. The extrados 16 of the rigid layer 7 has a roughness surface Ra of 50 µm. The rigid layer 7 has a thickness 2 mm wall uniform.

Immediately after layer molding rigid 7, a molded foam layer 8 is disposed on the surface of the rigid layer 7 by injection molding, with a material AES plastic containing 1% by weight of an expanding agent in microcapsules with a thermal expansion property. In this case, molded foam layer 8 adheres directly to extrados 16 of the rigid layer 7. The molded foam layer 8 is a body of molded foam with a foaming factor of 1.5 times. The layer of molded foam 8 that has been foamed and molded is directly adhered to the rigid layer 7. Thus, the foam layer is manufactured molded 8 provided with a large wall thickness. The method of Foaming and molding is as follows. At a cylinder temperature of the molding machine of 230 ° C and a cavity temperature of the 5 ° C mold is injected into the cavity the AES plastic material that Contains the expanding agent. Opening the mold a little immediately after, the contact surfaces of the blades and The mold suddenly cools. As a result, a outer layer 18 and the foamed state stabilizes when the mold. The outer layer 18 that is formed at this time has a Approximate thickness of 100 µm. The molded foam layer 8 It presents multiple foam cells.

The size of each foam cell in the layer of molded foam 8 is 1 mm maximum.

In this way, the rotor 2 is provided with the rigid layer 7 and the molded foam layer 8. The weight of the rotor manufactured is approximately 760 g, and the thickness of the part of Maximum wall thickness of the blades 6 is 20 mm. The diameter Maximum outer rotor 2 is 400 mm.

In figure 2, when the direction of rotation is the indicating the arrow, the extradós 16 corresponds to the side upper blade 6.

Execution Example 2

The cube 5 and the rigid layer 7 have been manufactured by injection molding, with an AES plastic material that Contains 20% by weight of fiberglass. The molded body is provided with a hub 5 positioned in the center and three rigid layers 7 protruding from the cube 5. The extrados 16 of the rigid layer 7 it has a surface roughness Ra of 100 µm. Rigid layer 7 has a uniform wall thickness of 2 mm.

Immediately after layer molding rigid 7, a molded foam layer 8 is disposed on the surface of the rigid layer 7 by injection molding, with a material AES plastic containing 2.5% by weight of an expanding agent in microcapsules with a thermal expansion property. The layer of molded foam 8 is provided with a molded foam body with a foaming factor of 2.0 times. The molded foam layer 8 that it has been foamed and molded is directly adhered to the layer rigid 7. Thus, molded foam layer 8 is provided with A large wall thickness. The foaming and molding method is the same than the one described in the embodiment 1.

In this way, the rotor 2 is provided with the rigid layer 7 and the molded foam layer 8. The weight of the rotor manufactured is approximately 670 g, and the thickness of the part of Maximum wall thickness of the blades 6 is 20 mm. The diameter Maximum outer rotor 2 is 400 mm.

Execution Example 3

The cube 5 and the rigid layer 7 have been manufactured by injection molding, with an AES plastic material that Contains 20% by weight of fiberglass. The molded body is provided with a hub 5 positioned in the center and three rigid layers 7 protruding from the cube 5. The extrados 16 of the rigid layer 7 it has a surface roughness Ra of 300 µm. Rigid layer 7 has a uniform wall thickness of 2 mm.

Subsequently, a layer of foam is arranged molded 8 on the surface of the rigid layer 7 by molding injection, with an AES plastic material containing 4% by weight of an expanding agent in microcapsules with a property of Thermal expansion. The molded foam layer 8 is provided with a Molded foam body with a foaming factor of 2.0. The layer of molded foam 8 that has been foamed and molded is directly adhered to the rigid layer 7. Thus, the foam layer is manufactured molded 8 provided with a large wall thickness. The method of foaming and molding is the same as described in the form of realization 1.

In this way, the rotor 2 is provided with the rigid layer 7 and the molded foam layer 8. The weight of the rotor manufactured is approximately 620 g, and the thickness of the part Maximum wall thickness of the blades 6 is 20 mm. The diameter Maximum outer rotor 2 is 400 mm.

Execution Example 4

The cube 5 and the rigid layer 7 have been manufactured by injection molding, with an AES plastic material that Contains 20% by weight of fiberglass. The molded body is provided with a hub 5 positioned in the center and three rigid layers 7 protruding from the cube 5. The extrados 16 of the rigid layer 7 it has a surface roughness Ra of 500 µm. Rigid layer 7 has a uniform wall thickness of 2 mm.

Subsequently, a layer of foam is arranged molded 8 on the surface of the rigid layer 7 by molding injection, with an AES plastic material containing 6% by weight of an expanding agent in microcapsules with a property of Thermal expansion. The molded foam layer 8 is provided with a Molded foam body with a foaming factor of 2.0. The layer of molded foam 8 that has been foamed and molded is directly adhered to the rigid layer 7. Thus, the foam layer is manufactured molded 8 provided with a large wall thickness. The method of foaming and molding is the same as described in the form of realization 1.

In this way, the rotor 2 is provided with the rigid layer 7 and the molded foam layer 8. The weight of the rotor manufactured is approximately 580 g, and the thickness of the part of Maximum wall thickness of the blades 6 is 20 mm. The diameter Maximum outer rotor 2 is 400 mm.

Execution Example 5

The cube 5 and the rigid layer 7 have been manufactured by injection molding, with an AES plastic material that Contains 20% by weight of fiberglass. The molded body is provided with a hub 5 positioned in the center and three rigid layers 7 protruding from the cube 5. The extrados 16 of the rigid layer 7 it has a surface roughness Ra of 800 µm. Rigid layer 7 has a uniform wall thickness of 2 mm.

Subsequently, a layer of foam is arranged molded 8 on the surface of the rigid layer 7 by molding injection, with an AES plastic material containing 8% by weight of an expanding agent in microcapsules with a property of Thermal expansion. The molded foam layer 8 is provided with a molded foam body with a foam factor of 5.0. The layer of molded foam 8 that has been foamed and molded is directly adhered to the rigid layer 7. Thus, the foam layer is manufactured molded 8 provided with a large wall thickness. The method of foaming and molding is the same as described in the form of realization 1.

In this way, the rotor 2 is provided with the rigid layer 7 and the molded foam layer 8. The weight of the rotor manufactured is approximately 550 g, and the thickness of the part of Maximum wall thickness of the blades 6 is 20 mm. The diameter Maximum outer rotor 2 is 400 mm.

Comparative example one

The cube 5 and the rigid layer 7 have been manufactured by injection molding, with an AES plastic material that Contains 20% by weight of fiberglass. AES plastic material Containing 20% by weight of fiberglass is the same as the which is used in the embodiment 1. The molded body is provided with a hub 5 positioned in the center and three rigid layers 7 protruding from the cube 5. The rigid layer 7 has the same shape that the blade 6 manufactured according to the embodiment 1. It is that is, blade 6 of this comparative example is composed only of the rigid layer 7.

The weight of the manufactured rotor is 1150 g approximately, and the thickness of the maximum wall thickness part of the blades 6 is 20 mm. The maximum outer diameter of rotor 2 It is 400 mm.

The rotor manufactured according to this comparative example 1 is heavier than rotors manufactured according to the examples of realization 1 to 5.

According to the mentioned embodiments previously, the surface roughness of the extradós 16 of the layer rigid 7 is greater, as is the body foaming factor formed molding adhered to the rigid layer 7 is larger. With this constitution, by adhering molded foam layer 8 low stiffness to the rigid layer 7, the adhesion strength of the layer rigid 7 and molded foam layer 8 improves.

In rotors manufactured according to the examples of embodiment 1 to 5, each of the three blades 6 presents the shape and The weight as designed. In addition, each of the three blades 6 presents the identical balance as designed in the form and the weight

If the rotors manufactured according to the examples of embodiment 1 to 5 are used in the outdoor unit fan from the air conditioner, you get a fan with the capacity of blowing needed. Even if you turn at maximum speed, the level of noise is low. The starting torque when starting the fan is small. In contrast, in the fan that is used in the rotor manufactured according to comparative example 1, a torque is required major starter, compared to rotors manufactured according to The realization examples.

According to the embodiments, the factor of Foamed molded foam layer is preferably between 1.5 and 4.0. If the foaming factor is less than 1.5, the rotor weight is not sufficiently reduced. Yes The foaming factor is greater than 4, the foam cells individual foamed body are large, variations of foaming state increase and fan rotation balance It tends to decrease. In addition, if the foaming factor is greater than 4, the mechanical resistance of the rotor tends to decrease.

According to the embodiments, they are manufactured the blades 6 with a maximum thickness of 20 mm and the rotor 2 with a maximum outside diameter of 400 mm, and can also be manufactured by the method of the invention a larger rotor. For example, it has been confirmed that it is possible to manufacture a rotor provided with a rigid layer and a 3 mm molded foam layer, blades with a maximum thickness of 30 mm and a maximum outer diameter of 70 mm.

The fan that uses the rotor of this great size also has the same effect and blowing performance Excellent mentioned above.

That is, in the rotor of the invention, the layer of Molded foam has a volume greater than that of the rigid layer. He Molded foam layer weight is extremely less than the rigid layer weight. Therefore, when a rotor is manufactured provided with large blades, if the size of the foam layer Light molded increases, the increase in rotor weight is small. Therefore, it is possible to manufacture a fan provided with blades whose overall dimensions are larger.

Instead of the AES plastic material used in the embodiments, other materials can be used plastics to manufacture the same rotor provided with the rigid layer 7 and molded foam layer 8 as indicated in the form of embodiment 1. Other plastic materials are not particularly restricted, including, for example, polypropylene resin, polycarbonate, polyamide resin, polyester resin, resin polyacetal, polyacrylic resin, polystyrene resin, rubber ethylene propylene and its copolymers.

As a plastic material, in particular, it is a material with excellent resistance to outdoor. When the rotor molded by such material with a excellent weather resistance is used in the fan of the outdoor unit of the air conditioner, it can be used over a long period of time with stable performance.

Instead of the fiberglass used in the exemplary embodiments, a plastic material can be used that contain another load, and the same rotor can be manufactured with rigid layer 7 and molded foam layer 8 than specified in the embodiment 1. Another load is not particularly restricted, inorganic powder material, material can be used Organic powder or fibrous powder material. Such charges have The function of improving the mechanical strength of the rigid layer.

The blowing or blowing agent is not particularly restricted, but can be used, between others, a material that releases gases during molding, and a material that emits gases when heated during molding.

According to the embodiments, after forming the rigid layer by injection molding, when forming immediately molded foam layer, rigid layer and layer molded foam adhere, but the method is not restricted to this, other manufacturing methods can also be used. By For example, if an adhesive or similar is used, the rigid layer and the separately formed molded foam body can adhere one to another.

By the way, the rigid layer and the foam layer molded can be manufactured by another molding method, such as the method of compression molding or transfer molding. Do not However, the injection molding method is best for massive production.

As follows from the examples of embodiment Above, the molded foam layer achieves the properties of Big thickness and light weight. Therefore, it can be obtained easily a large diameter rotor. As a result, the performance of the fan increases.

The fan according to the embodiments it is used in the outdoor unit of the conditioner, but not It is limited to this use, it can also be used also in a cooling device of an electronic device domestic, an air circulation device intended to make circulate the air or a fan to generate wind. However, the above effects improve particularly if used in the fan that requires a large rotor.

Claims (26)

1. Rotor used in a fan, which understands: a cube (5) and a shovel (6), wherein said blade includes a part of multiple layers (7, 8), characterized in that said multilayer part includes a rigid layer only on an air receiving surface in the intrados (15) of said blade (6) and includes a molded foam layer (8) adhered to said rigid layer in the extrados (16 ). 2. Rotor according to claim 1, wherein said multiple layers (7, 8) have a two layer structure consisting of a first layer (8) and a second layer (7), and said first layer has said foam layer molded (8). 3. Rotor according to claim 2, wherein said molded foam layer is arranged in the extrados (16) when said fan rotates. 4. Rotor according to claim 2 or 3, wherein said molded foam layer has a thickness greater than that of said second layer. 5. Rotor according to claim 1, wherein said multiple layers have a rigid layer (7) and said molded foam layer (8) laminated in said rigid layer, said rigid layer has a resistance mechanical greater than said molded foam layer, and said molded foam layer has a specific density lower than said rigid layer. 6. Rotor according to claim 1, wherein said multiple layers have a rigid layer (7) said molded foam layer (8) laminated in said rigid layer, and a surface layer (18) formed on the surface of said molded foam layer. 7. Rotor according to claim 1, in which said blade is provided with a plurality of blades (6), and said plurality of blades is arranged symmetrically in a circumference of said cube. 8. Rotor according to claim 1, wherein said molded foam layer is provided with a foam factor between 1.5 and 4. 9. Rotor according to claim 1, wherein said multiple layers have a rigid layer, and said molded foam layer laminated in said layer rigid said rigid layer is provided with a body plastic molding, and said molded foam layer is provided with a Foam body molded with plastic. 10. Rotor according to claim 1, wherein a first surface of said layer rigid has a surface roughness (Ra) between 50 \ mum and Ra 500 \ mum, and said molded foam layer is directly adhered to said first surface. 11. Rotor according to claim 1, wherein said molded foam layer is provided with multiple foam cells. 12. Rotor according to claim 1, wherein said fan is used in a outdoor unit of an air conditioner. 13. Method for manufacturing a rotor used in a fan, comprising: a first stage of molding a hub (5) and a first layer of shovel (7) protruding from said bucket, and a second stage of lamination of a second blade layer (8) having a molded foam layer (8) in said first layer of shovel. 14. Manufacturing method according to claim 13, wherein said first stage includes a stage of injection molding of a plastic material. 15. Manufacturing method according to claim 13 or 14, wherein said first stage includes a stage of molding said first layer of shovel so that the roughness surface of a first surface of said first blade layer it may be in the range between Ra 50 µm and Ra 500 \ mum, and said second stage includes an adhesion stage of said molded foam layer to said first surface. 16. Manufacturing method according to claim fifteen, wherein said first surface, which is the extradós (16) in a sense of the rotation of said rotor, is adhered to said molded foam layer (8). 17. Manufacturing method according to any of the claims 13 to 15, wherein said second stage includes a stage for molding said second blade layer so that a factor of foaming of said molded foam layer can be between 1.5 to 4 approximately. 18. Manufacturing method according to any of the claims 13 to 17, wherein said second stage also includes a formation stage of an outer layer (18) on a surface of said molded foam layer (8). 19. Manufacturing method according to any of the claims 13 to 18, wherein said second stage includes a stage of injection molding of a plastic material that presents the less a foaming agent and an expanding agent. 20. Manufacturing method according to any of the claims 13 to 19, wherein said second stage includes a stage of molding such that said molded foam layer can Contain multiple foam cells. 21. Fan comprising: a motor (3), a hub (5) connected to said motor, and a shovel (6) protruding from said bucket, wherein said blade includes a multi-layer part (7, 8), characterized in that said multi-layer part includes a rigid layer (7), which is arranged on an air receiving surface in the intrados (15) of said blade , and includes a molded foam layer (8) adhered to said rigid layer in the extrados (16), and said blades are rotatable by means of the said motor drive. 22. Fan according to claim 21, wherein said rigid layer is provided with a plastic molded body, and said molded foam layer is provided with a plastic molded foam body provided with multiple cells of foam 23. Fan according to claim 21, wherein said molded foam layer is arranged in the extrados (16) when turning said blade. 24. External unit of an air conditioner that understands: a heat exchanger (12), a fan (10) installed on a rear side of said heat exchanger, wherein said fan includes: a motor (3), a hub (5) connected to said motor, and a shovel (6) protruding from said bucket, said shovel including a part of multiple layers (7, 8), characterized in that said multilayer part includes a rigid layer (7), which is arranged on an air receiving surface in the intrados (15) of said blade, a molded foam layer (8) adhered to said rigid layer on the extrados (16), and said blades are rotatable by means of the said motor drive. 25. Outdoor unit according to claim 24, wherein said rigid layer is provided with a plastic molded body, and said molded foam layer is provided with a plastic molded foam body featuring multiple cells of foam 26. Outdoor unit according to claim 24, wherein said molded foam layer is arranged in the extrados when turning said shovel.