JPH03199697A - Cross flow fan for air conditioner and method for manufacturing the same - Google Patents

Abstract

PURPOSE:To make a blade part thin while aiming at obtainment of molding property and dynamic balance by embedding metallic plates in a longitudinal direction of fan blade portions made of glass fiber mixed reinforced plastic mold. CONSTITUTION:SUS plates 7 are inserted in blade molds 10 in a longitudinal direction and glass fiber reinforced resin material is injected in a mold 8 for injection molding. The resin material is filled in an end plate mold portion in the vicinity of an injection port 11 side, then, pressed in the blade mold 10 near the injection port 11 side. The resin material is supplied under pressure in spaces 10a which are defined between mold surfaces on the injection port 11 side largely separated from each other on the outside and having small resistances and the SUS plates 7 opposite thereto, and the filling of the resin material is carried out in turn so that the entire inside of the molds for the injection molding is filled with the resin material. The SUS plates 7 are pressed to the stream-line shaped inside of the blade mold 10 by the injection pressure to coincide with the facing mold portion of the blade mold 10. Consequently, even if the blade portion is thin, the lowering of strength, etc., can be compensated by the SUS plates 7, so that the change of dynamic balance is small even at the time of warming.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a cross-flow fan for an air conditioner used in an indoor unit of an air conditioner, and a method for manufacturing the cross-flow fan.

(Prior Art) There are many demands for devices equipped with cross-flow fans to be smaller and lighter, and accordingly cross-flow fans are also being made smaller and lighter. Therefore, cross-flow fans generally use thin fan blade sections.

However, because the fan blades of cross-flow fans are thin, their mechanical strength is weak, causing eccentricity of rotation at 1f.
There is a risk that the dynamic balance may change.

Therefore, reinforced plastic mixed with glass fiber has been conventionally used in cross-flow fans as a highly rigid material. Typically, acrylonitrile, styrene 28
Glass fiber-reinforced AS resin materials are used, which are made by blending glass fibers into AS resin materials made of monomers. Then, through injection molding using this glass fiber-reinforced AS resin material, fan assemblies that are each part are molded, and these fan assemblies (fan molded products) are combined to form the fan body of the cross-flow fan. ing.

Incidentally, in recent years, especially in the field of air conditioner products, there has been a demand for thinner walls and smaller sizes. Along with this, cross-flow fans are required to be thinner and smaller than ever in order to improve fan performance.

However, if the fan blade portion is simply made thinner, the reinforcing effect of the glass fibers, such as strength, will be reduced, resulting in many problems. Particularly for air conditioners, if the reinforcing effect is reduced, the fan blades are likely to deform due to high-temperature warm air during heating, which changes the dynamic balance of the cross-flow fan and makes rotation unstable.

(Problem to be Solved by the Invention) Therefore, in order to improve the reinforcing effect, the amount of glass fiber blended should be increased or the length of the glass fiber should be lengthened. It is also conceivable to make the fan blade part metal.

However, increasing the amount of glass fiber blended or lengthening the glass fiber length significantly reduces the fluidity of the injection molding material. This causes problems such as difficulty in molding.

Furthermore, the latter structure in which the fan blades are made of metal is fundamentally difficult. That is, although the fan blade portion of a cross-flow fan has a streamlined shape in order to reduce the generation of noise, it is difficult to fabricate this streamlined fan blade from metal.

Moreover, it also has the disadvantage of being quite heavy.

This invention was made with attention to the above circumstances, and its first purpose is to pursue thinning of the fan blade portion while ensuring moldability and reducing changes in dynamic balance. The purpose of the present invention is to provide a cross-flow fan for air conditioners that can be used in air conditioners.

In addition to the above-mentioned effects, the second objective is to improve the I! It is an object of the present invention to provide a method for manufacturing a cross-flow fan, which makes it possible to mold the above-mentioned metal plate built-in cross-flow fan in which the fm balance is kept constant.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the first object, the cross-flow fan for an air conditioner according to claim 1 is a fan made of reinforced plastic mixed with glass fiber. The reason is that a metal plate is embedded within the fan blade portion in the longitudinal direction of the fan blade portion.

Furthermore, in order to achieve the second object, the method for manufacturing a cross-flow fan according to claim 2 provides a method for manufacturing a cross-flow fan, in which a row is formed on the side surface of the end plate mold part for forming the end plate and the mold part that communicates with the end plate mold part. An injection molding mold having a blade mold part for molding fan blades protruding from above is provided, and within each of the blade mold parts, one side surface in the row direction of the blade mold part uniformly follows the shape of the same side part. A metal plate of the same shape is arranged in the longitudinal direction, and then plastic is injected into the injection mold from a portion of the end plate mold part corresponding to the other end in the row direction of the blade mold part to assemble the fan. The purpose is to mold the

(Function) According to the cross-flow fan for an air conditioner according to claim 1, the metal plate inserted in the fan blade portion compensates for the decrease in strength etc. due to thinning of the fan blade portion made of glass fiber reinforced plastic. (Maintaining reinforcing effect)
.

This means that the fan blade made of glass fiber reinforced plastic can be made much thinner due to the reinforcing effect of the metal plate. Furthermore, it is resistant to heat, so even when heating is performed by blowing out high-temperature air, the dynamic balance hardly changes.

In addition, since the metal plate is embedded in the fan blade made of glass fiber reinforced plastic, there is no need to increase the amount of glass fiber blended or use long glass fiber, and the formability of the crossflow fan is not compromised. I'm done. Moreover, since the metal plate only occupies a portion of the fan blade, weight reduction is not compromised.

According to the method for manufacturing a cross-flow fan according to claim 2, when plastic is injected from the end plate mold part, the plastic first fills the end plate mold part closest to the injection side, and then fills the end plate mold part closest to the injection side. It is press-fitted into the blade mold.

Here, since the metal plate is placed on the side opposite to the injection side, the plastic is placed in the space between the mold surface on the injection side of the blade mold part and the metal plate facing it, which is widely separated. (resistance: small).

This plastic filling is performed in order from the fan blade mold part on the injection side, and the inside of the injection mold is filled with plastic. Then, the metal plate in each blade mold part is pressed against one side of the blade mold part following the side shape by the plastic injection pressure. In other words, each metal plate is positioned at the same position on the blade mold section. Thus, each metal plate is inserted on the same side and in the same location of each fan blade section of the injection molded crossflow fan.

Therefore, even if the metal plate is inserted, the weight balance of each fan blade portion of the cross-flow fan can be kept constant.

(Example) This invention will be described based on an example shown in FIGS. 1 to 9. FIG. 2 shows a cross-flow fan for an air conditioner used as an indoor fan of an air conditioner to which the present invention is applied, and 1 is the fan body. The fan main body 1 has a structure in which a plurality of fan assemblies 2 shown in FIG. 3 are combined.

That is, the fan assembly 2 has a thin and elongated fan blade part 4 having a streamlined cross section as shown in FIG.
It has a structure in which a plurality of protrusions are provided in the same direction along the circumferential direction. Then, a plurality of fan assemblies 2 are joined together in the axial direction by ultrasonic welding, and a semi-cylindrical part 5 is formed.
The semi-cylindrical part 5 is made into a pair of parts, and both parts are ultrasonically welded in the same manner, thereby constructing the fan main body 1 having a small diameter and cylindrical shape. Note that 6 is a rotating shaft portion provided at both ends of the fan main body 1.

The fan body 1 is made of reinforced plastic containing a large number of glass fibers, such as glass fiber reinforced AS (acrylic nitrile styrene) resin material. Inside each fan blade portion 4 of the fan body 1, a thin metal plate, for example, a thin metal plate having a thickness of 0.2 m+s as shown in FIG.
A band-shaped SUS plate 7 of J is inserted in the longitudinal direction.

This SUS plate 7 insert is manufactured using a manufacturing method that allows each SUS plate 7 to be placed at the same position in order to ensure the dynamic balance of the cross-flow fan. A method of manufacturing this cross-flow fan is shown in FIGS. 6-8.

Here, the manufacturing method will be explained using each figure. In FIGS. 6 and 7, 8 is an injection mold for molding the fan assembly 2. The injection mold 8 includes, for example, a block-shaped mold part 8a and a plate-shaped mold part 8 that comes into contact with and separates from the block-shaped mold part 8a.
Consists of b. As shown in FIG. 6, between the boundary between the two mold parts 8a and 8b, a pair of end plate mold parts 9, 9 having a semicircular plate shape are provided for forming the end plate 3. are provided in a circular manner as shown in FIG.

Further, the mold part 8b includes a plurality of blade mold parts 10 arranged in a row in an arc shape for forming the plurality of fan blade parts 4 at the end plate mold part 9.
．． It is provided every 9 along a direction perpendicular to the boundary between both mold parts 8a and 8b.

Ends of the plurality of blade mold parts 10 on the mold component 8a side communicate with the end plate mold part 9. That is, as shown in FIG. 8, the blade mold part 10 is in a state of protruding from the side surface of the end plate mold part 9. In addition, an injection port 11 is provided in the row direction of each blade mold part 10, for example, on the end face of the blade that intersects with the extension line toward the streamlined outer surface side.

These injection port portions 11.11 communicate with an injection portion 13 of an injection machine (not shown) via a collection path 12,
The glass fiber reinforced AS resin material can be injected from the injection machine into each pair of end plate mold part 9 and fan blade mold part 10.

Then, using this injection mold 8, each of the above SUS plates 7
are inserted in the same position.

That is, first, the SUS plate 7 having a thickness of 0.2+neJ is placed in each blade mold part 10 in a shape that follows the streamlined inner surface shape as shown in FIG. It is inserted along the longitudinal direction of the blade mold part 10 so as to follow the inner surface of the streamlined shape.Then, the glass fiber reinforced AS resin material is injected into the injection mold 8 from an injection machine. First, fiber reinforced AS resin materials are
After filling the end plate mold portion closest to the injection port 11 side, it is press-fitted into the blade mold portion 10 closest to the injection port 11 side (as shown in FIG. 8, however, the SUS plate 7 is omitted).

Here, the SUS plate 7 is on the streamlined inner surface side (injection port 11 side)
Therefore, as shown in FIG. 7, the glass fiber reinforced AS resin material is placed between the mold surface on the injection port 11 side of the blade mold section 10 and the mold surface opposite thereto, which has low resistance and is widely spaced on the outside. It is press-fitted into the space 10a between the SUS plate 7 and the SUS plate 7.

Then, next, 1. of the blade mold part 10 which is the second closest to the injection port part 11. :A glass-reinforced AS resin material is press-fitted into the il space 10a.

The glass fiber reinforced AS resin material is filled in order from the fan blade mold section 1o on the side of the injection port 11, and the entire injection mold 8 is filled with the glass fiber reinforced AS resin material. At this time, the SUS plate 7 in each blade mold part lo is pressed against the streamlined inner surface (one side) of the blade mold part 1o following the same side surface shape due to the injection pressure, and the SUS plate 7 in each blade mold part lo is pressed against the streamlined inner surface (one side) of the blade mold part 1o, It will match the mold surface.

As a result, each SUS plate 7 is positioned and inserted at the same position on the same inner surface of the blade mold part 10, as shown in FIG. Even if there is variation as shown,
Each SUS plate 7 has each injection molded fan blade part 4.
They will be inserted on the same side and in the same position.

However, with the structure in which the SUS plate 7 is buried in the blade part 4 as described above, even if the fan blade part 4 made of glass fiber-reinforced As resin becomes considerably thin, the strength of the 5 USU plate 7 is reduced. (maintenance of reinforcing effect).

This means that even though the pursuit of smaller size and lighter weight advances, SUS
Due to the reinforcing effect of the plate 7, this can be considerably coped with. In other words, the fan blade portion 4 made of glass fiber reinforced As resin can be made significantly thinner. Of course, it also becomes more resistant to heat, so even during heating, which blows out high-temperature air, the dynamic balance changes very little.

Furthermore, the structure in which the SUS plate 7 is embedded in the fan blade portion 4 eliminates the need to change the blending amount of glass fiber or use long glass fiber, so the formability of the cross-flow fan is not impaired. Furthermore, since the SUS plate 7 only occupies a part of the fan blade portion 4, weight reduction can be achieved without compromising the weight reduction.

In addition, by adopting the manufacturing method in which the SUS plate 7 is uniformly pushed to one side of the blade mold part 1o and inserted under the pressure of the above-mentioned injected resin material, each fan of the cross-flow fan, which is likely to be disturbed by the insertion of the SUS plate 7, is This has the advantage that the weight balance of the blade portion 4 can be kept constant, and the generation of noise when the fan rotates can be suppressed.

These effects have been confirmed through a series of experiments that determined the ``dynamic balance change'' and ``noise'' of the cross-flow fan.

In terms of this experiment, it contrasted two different cross-flow fans with the example cross-flow fan.

Specifically, as Comparative Example 1, a glass fiber-reinforced AS resin material was inserted into the side surface of the end plate 3 and the end plate mold part as shown by the two-dot chain line in FIGS. 3 and 7 without inserting a metal plate. A conventional galvanometric fan for an air conditioner was used, in which the fan body 1 was constructed by joining the fan assembly 2 obtained by injection molding from three positions indicated by the symbol X in 9 by ultrasonic welding. In addition, as Comparative Example 2, “SU with a thickness of 0.2 mmJ”
Put the S plate 7 into the injection mold 8, and as in Comparative Example 1 above,
For an air conditioner, a fan assembly 1 obtained by injection molding glass fiber-reinforced AS resin material from the side surface 3 of an end plate 3 and three injection ports X of an end plate mold part 9 is joined by ultrasonic welding. A cross-flow fan was used.

Using the embodiment of the present invention, Comparative Example 1, and Comparative Example 2, we investigated the relationship between dynamic balance changes due to environmental temperature (Aglngu) and the air volume and noise when the air conditioner is operated by actually incorporating it into an indoor unit. was measured.

As a result, as shown in the following table, the dynamic balance change of the conventional cross-flow fan for an air conditioner of Comparative Example 1 was ro, 6 gJ. On the other hand, the cross-flow fan for air conditioner of Comparative Example 2 had a large dynamic balance change of ro, 93 g, and the dynamic balance change of the cross-flow fan of Example was small, ro of 48 gJ. It was something that existed.

Considering this result, since the cross flow fan for air conditioner of Comparative Example 2 uses a method in which the resin material is injected from three injection ports X of the end plate mold part 9, , both SUS plates 7 of the blade mold part arranged on both sides
It is recognized that the position of the SUS plate 7 varies as the SUS plate 7 receives pressure from different directions. In other words, in a cross-flow fan formed by this method, the position of the SUS plate 7 differs from fan blade part 4 to fan blade part 4, which causes a change in dynamic balance to be disturbed.

However, since the cross-flow fan of the present invention is injection molded from one side, which is different from the conventional method, each inserted SUS plate 7 can be precisely positioned on the same surface. However, it can be said that this difference is manifested as a change in dynamic balance.

On the other hand, looking at the measurement results for "noise", as shown in FIG. It was confirmed that the noise was equivalent to that of a cross-flow fan for air conditioners. However, considering that the noise characteristics were poor in Comparative Example 2, the good noise characteristics can be attributed to the fact that the SUS plate 7 was inserted into the same surface of the fan blade portion 4 as described above. I understand.

In one embodiment, the SUS plate was inserted into the inner surface of the fan blade portion of the cross-flow fan, but it goes without saying that the SUS plate may be inserted on the same surface as the outer surface. Further, although an example in which a SUS plate with a thickness of 0.2+a+*J was inserted was given as an example, the present invention is not limited to this, and other thin metal plates may be inserted into the fan blade portion.

[Effects of the Invention] As explained above, according to the invention set forth in claim 1, it is possible to significantly reduce the thickness of the fan blade portion while ensuring moldability and reducing changes in dynamic balance. We can provide a cross-flow fan for air conditioners that is extremely lightweight.

According to the second aspect of the present invention, in addition to the above-mentioned effects, it is possible to form a cross-flow fan with a built-in metal plate in which the weight balance of each fan blade portion is kept constant.

[Brief explanation of drawings]

FIGS. 1 to 9 show one embodiment of the present invention.
The figure is a partial perspective view showing the fan blade part of a cross-flow fan in which a metal plate is inserted, FIG. 2 is a perspective view showing the external appearance of a cross-flow fan to which this invention is applied, and FIG. FIG. 4 is a perspective view of the fan assembly from the outside, FIG. 4 is a perspective view of the fan assembly from the inside, FIG. 5 is a perspective view of the metal plate inserted into the fan blade, and FIG. 6 is the fan assembly made by injection molding. FIG. 7 is a side sectional view showing the end plate mold part and the blade mold part of the injection mold, FIG. FIG. 9 is a graph showing the noise performance of a cross-flow fan according to an embodiment of the present invention in comparison with the noise performance of a conventional cross-flow fan and a cross-flow fan in which a metal plate is inserted using a different manufacturing method. It is. 1...Fan body, 2...Fan assembly, 3...
End plate, 4...Fan blade part, 7...SUS plate (
metal plate), 8... injection mold, 9... end plate mold part, 1
0... Blade mold part, 11... Injection port part.

Claims (2)

[Claims] (1) In a cross-flow fan for an air conditioner whose fan blade portion is constructed from a molded product of reinforced plastic mixed with glass fiber, a metal plate is embedded within the fan blade portion along the longitudinal direction of the fan blade portion. This is a cross-flow fan for air conditioners. (2) providing an injection mold comprising an end plate mold part for end plate molding and a blade mold part for fan blade molding that protrudes in a row from the side surface of the mold part communicating with the end plate mold part; Inside each of the blade mold parts, a metal plate having an outer shape that follows the shape of the same side surface uniformly is disposed on one side surface of the blade mold part in the row direction, and then, a metal plate having an outer shape that follows the shape of the same side surface part is disposed uniformly on one side surface of the blade mold part in the row direction. A method of manufacturing a cross-flow fan, comprising injecting plastic into the injection mold from a portion of the end plate mold portion corresponding to an end of the fan assembly.