JPH1122696A - Blade of axial fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-weight blade of an axial fan, superior in the corrosion resistance with a low cost. SOLUTION: This blade of an axial fan comprises a blade part 1 and a root flange part 2. The blade part 1 comprises a skin 3 made of a fiber-glass reinforced plastic composite material, and an internal filler material 4 made of a resin foam body such as urethane foam. The root flange part 2 is made of a fiber-glass reinforced plastic composite material. The root flange part 2 comprises bolt holes formed by cutting, and the metallic bolts 5 for mounting to a rotor shaft, are fixed to the holes by the screwing and the adhesion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight composite blade applied to an axial fan such as an axial blower for thermal power generation or an axial blower for a wind tunnel.

[0002]

2. Description of the Related Art Conventionally, blades for large axial fans (blowers) for thermal power generation are often made of aluminum alloy, carbon steel or alloy steel. Among them, blades of an axial flow blower for flue gas desulfurization equipment are made of high-grade stainless steel or Inconel 62 from the viewpoint of corrosion resistance and wear resistance.
5. Ni-based alloys such as Hastelloy are used.

Since the axial fan rotates a blade attached to a rotor (rotor) at a high speed of several hundred rpm, the weight of the blade directly affects the weight and structure of the entire apparatus. That is, the smaller the weight of the rotor, the smaller the weight of the rotor or the bearing that supports the rotor to which the blade is attached, the smaller and lighter the blade.

A mechanism (variable pitch mechanism) for changing the angle of the blade attached to the rotor in accordance with the air flow has a structure in which the blade is rotated by a hydraulic device via a mechanism such as a gear, and the weight of the blade is reduced. Therefore, the structure of the variable pitch mechanism can be simplified and downsized.

In recent years, there has been a strong demand for downsizing and downsizing of axial flow fans and significant cost reduction of the entire apparatus, and there is a limit in meeting this demand with blades made of currently used metal materials. There was a need for materials and structures to achieve weight reduction of the blade.

On the other hand, in the case of an axial fan for a flue gas desulfurization apparatus, as described above, high-grade stainless steel or Inconel 625 is used as the blade material from the viewpoint of corrosion resistance and wear resistance.
Very expensive Ni-based alloys such as Hastelloy are used.

However, corrosion may occur even when such a corrosion-resistant material is used, particularly in a severely corrosive environment, and a resin coating having excellent corrosion resistance is applied as necessary. Furthermore, since the material used is a very expensive material, the price of the blade has increased the price of the entire apparatus, and the development of a low-cost blade material having excellent corrosion resistance has been required.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the conventional axial fan blades, and has as its object to provide an inexpensive axial fan blade that is lightweight, has excellent corrosion resistance, and is inexpensive. It is an issue.

[0009]

According to the present invention, there is provided an axial flow fan blade comprising a blade portion and a blade root flange portion, wherein the blade portion and the blade portion flange are formed of a fiber-reinforced plastic composite. A blade for an axial fan integrally formed of a material is provided.

As the fiber reinforced plastic composite material, one obtained by laminating one or both of a glass fiber reinforced plastic composite material and a carbon fiber reinforced plastic composite material can be used.

[0011] The fiber-reinforced plastic composite material constituting the blade of the present invention has a lower density than the metal material, so that the blade according to the present invention can greatly reduce the weight.
Further, the fiber-reinforced plastic composite material has high strength, and by adjusting the amount and orientation of the fiber, it is possible to optimize the structural design as a blade of the axial flow fan.

Further, in the blade of the axial flow fan according to the present invention, the wing portion may be constituted by an outer cover made of a fiber-reinforced plastic composite material and an internal filler filled inside the outer cover.

Further weight reduction can be achieved by using a resin foam or the like as the internal filler.

In the blade of the axial fan according to the present invention,
The blade root flange may be provided with a means for attaching the blade to the rotor. As the attachment means, a metal bolt, a metal nut, or a metal flat plate embedded in the blade root flange may be employed.

In the blade of the axial flow fan according to the present invention, the blade has a structure in which a thin metal plate or a polymer-based coating material is adhered to at least a part of the surface of the blade, for example, the leading edge of the blade. Abrasion resistance and erosion resistance can be improved.

Further, the blade of the axial flow fan according to the present invention may be configured such that a mounting jig directly integrated with the blade portion is provided without providing the blade root flange. With such a configuration, the blade structure is further simplified, the manufacturing process is simplified, and the cost can be further reduced.

In this case, the mounting jig integrated with the wing may be made of metal or carbon fiber reinforced composite material.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A blade of an axial fan according to the present invention will be specifically described below with reference to the embodiments shown in FIGS. In the following embodiments, the same components are denoted by the same reference numerals, and a duplicate description thereof will be omitted.

(First Embodiment) First, a blade according to a first embodiment shown in FIG. 1 will be described. The blade shown in FIG. 1 comprises a blade 1 and a blade root flange 2 attached to a rotor, both of which are made of glass fiber reinforced plastic composite. The wing 1 is composed of an outer skin 3 and an inner filler 4.

The blade section 1 and the blade root flange section 2 constituting this blade can be formed as an integral structure made of a glass fiber reinforced plastic composite material.

The glass fiber reinforced plastic composite material constituting the blade has a density of 1.5 to 1.8 g / cm ^3.
And about 1/5 of steel material, and 4 for aluminum alloy
As small as a comparatively small blade,
Significant weight reduction is possible. In terms of cost, this material is one of the cheapest materials among composite materials.

The glass fiber reinforced plastic composite material has a material strength at least equal to or higher than that of an aluminum alloy, so that the amount and orientation of the glass fiber can be adjusted according to the required characteristics, and an optimum structural design can be achieved. It is possible. In addition, glass fiber reinforced plastic composite materials can easily impart heat resistance and corrosion resistance by selecting the resin to be used, and are applied to blades of axial fans for flue gas desulfurization equipment with severe corrosive environment. Is also possible.

The form of the glass fiber is a fiber cloth aligned in one direction, a woven fabric (plain woven cloth) formed of warp and weft, a short fiber (glass chop), or a chopped mat made of the same. However, when strength is required, a structure including a large number of one-way cloths, plain weave cloths, and the like is adopted.

A glass chop made of short fibers in a mat shape can be used as the internal filler 4. In the blade structure of FIG. 1, the portion of the internal filler 4 may be a hollow or lightweight resin foam (for example, urethane foam) depending on the case, or may have the same configuration as the outer skin 3.

It is important that the outer skin 3 from the wing portion 1 to the blade root flange portion 2 is arranged so that glass fibers are continuous. In particular, the boundary between the blade portion 1 and the blade root flange portion 2 is a portion where both the bending force and the tensile force are maximized, and it is necessary to continuously laminate glass fibers and simultaneously make the structure smooth.

If there is no problem in terms of price, an integrated structure using a carbon fiber reinforced plastic composite material may be used. The effect obtained is the same, but the carbon fiber reinforced plastic composite material has much better strength characteristics than the glass fiber reinforced plastic composite material, so that the weight of the blade can be further reduced.

Next, a description will be given of an example of the structure of the blade of this embodiment which was actually produced as a trial and the constituent materials thereof. The raw material is an epoxy resin as a matrix resin and a plain weave roving cloth (320 g /
m ² ) and a glass chop (fiber length: 2 to 3 cm).

The outer skin 3 from the wing portion 1 to the blade root flange portion 2 is formed by coating a required number of plain weave roving cloths from the wing portion 1 so that the glass content of the composite material becomes 50 to 53 wt%. It was arranged continuously to the flange portion 2. The internal filler 4 has a glass content of 50 to
It was arranged to be 55 wt%.

The method of manufacturing the blade is such that a required amount of glass fiber of a predetermined form is filled in a molding die, and then an epoxy resin is injected. High-temperature heat curing at 120 ° C. was performed to obtain a composite blade made of a glass fiber reinforced plastic composite.

The blade is attached to a rotor (rotor) shaft by drilling a bolt hole at a predetermined position of a blade root flange by machining, fixing a metal bolt 5 by screwing and bonding, and fixing the bolt. And a method of tightening to the rotor shaft via

A cutting test was performed to confirm the properties of the manufactured composite material blade. As a result, there were almost no defects such as unfilled portions of resin, and the material was good. Density: 1.68 to 1.75 g /
cm ³ , tensile strength: 28 to 30 kgf / mm ² , satisfying the target.

In addition, a wing structure strength test such as a bending test and a tensile test was conducted using the actual wing, but the wing did not break even with an additional force three times the required strength. It was proved that application to a product was sufficiently possible to the extent that a slight crack was formed in the composite material portion where was screwed. Further, the weight of the obtained composite material blade was reduced to 1/4 of that of a conventional metal blade, and a great weight reduction was achieved.

The cost can be reduced by about 30% per blade as compared with an axial fan blade (using high-grade stainless steel or Ni-based alloy such as Inconel 625 or Hastelloy) for a flue gas desulfurization unit. is there.

In the above-described example, if there is no particular problem of cost, an integrated structure using a carbon fiber reinforced plastic composite material may be used. By using this material, the weight of the blade can be further reduced, so that the entire axial flow fan device can be significantly reduced in size, size, and weight.

(Second Embodiment) Next, a blade according to a second embodiment shown in FIG. 2 will be described. The blade shown in FIG. 2 comprises a blade portion 1 and a blade root flange portion 2 attached to a rotor, and is made of a glass fiber reinforced plastic composite material. The wing is composed of an outer skin 3 and an inner filler 4.

In the blade root flange portion 2, a hole in which a metal nut 15 for attaching the blade to the rotor is arranged is machined at a predetermined position, and the metal nut 15 is fixed with the adhesive 6. . With such a structure, a lightweight composite material blade that can be firmly and securely attached to the rotor shaft can be obtained.

Next, a description will be given of an example of an actually manufactured blade according to the present embodiment. With the same material and manufacturing method as in the case of the prototype example in the first embodiment, after manufacturing a blade made of glass fiber reinforced plastic composite material,
A stepped hole for mounting a metal nut 15 in the blade root flange 2 is drilled at a predetermined position by machining, and the metal (chrome-molybdenum steel) nut 15 is bonded with an epoxy-based room temperature curing adhesive 6. The adhesive was fixed.

In order to confirm the strength and breaking state of the blade root flange 2 of the manufactured blade, the blade root flange 2 was fixed to a tensile tester by bolting, and a tensile test was performed in which the blade was pulled.

As a result, even with an additional force three times the required strength similar to the experimental example in the case of the first embodiment, no cracks were found in any of the blade portion and the blade root flange. ,
No cracks were observed in the composite material portion where the metal bolts of the blade root flange were screwed, and it was confirmed that the blade had a higher strength than the blade structure in the first embodiment.

As described above, in the blade according to the second embodiment, the structural strength of the blade root flange is improved, and the blade can be further thinned and downsized. In particular, in the case of the second embodiment, the manufacturing cost is further reduced because it is not necessary to drill holes for screwing the glass fiber reinforced plastic composite material of the blade root flange.

Further, in the case of the second embodiment, the blade is attached between the metal nut and the metal bolt, so that it is possible to easily and firmly attach the blade by ordinary torque management.

(Third Embodiment) Next, a blade according to a third embodiment shown in FIG. 3 will be described. The blade shown in FIG. 3 also includes a blade portion 1 and a blade root flange portion 2 attached to a rotor, and is made of a glass fiber reinforced plastic composite material. The wing is composed of an outer skin 3 and an inner filler 4.

In order to attach the blade to the rotor, a metal flat plate 25 of a required size is buried in a predetermined position in the inside of the blade root flange 2 at the time of manufacture. With such a structure, a lightweight composite material blade that can be more firmly fixed to the rotor shaft can be obtained. It should be noted that a required number of metal nuts may be embedded in predetermined positions instead of the metal flat plate 25.

Next, a description will be given of an example of a blade according to the present embodiment, which is actually produced on a trial basis. A blade made of a glass fiber reinforced plastic composite material is manufactured using the same material and manufacturing method as in the first embodiment, but the blade root flange portion 2 is manufactured.
A method of embedding a metal (chromium-molybdenum steel) flat plate 25 of a required size in a predetermined position in advance at the time of lamination of glass fibers into a predetermined position, and then injecting an epoxy resin and integrally curing the same is adopted.

After manufacture of the blade, screw holes for fastening the blade to the rotor shaft were formed at predetermined positions of the blade root flange portion 2. In order to confirm the strength and fracture state of the blade root flange 2 of the manufactured blade, a tensile tester was used to check the blade root flange 2.
Was fixed with bolts, and a tensile test was performed to pull the wings.

As a result, even with an additional force three times the required strength similar to that of the first embodiment, no crack was found in any of the wing portion and the blade root flange, and the blade root was not observed. No crack was found in the composite material portion where the metal bolt of the flange portion was screwed, and it was confirmed that the composite material had higher strength than the wing structure according to the first embodiment.

(Fourth Embodiment) Next, a blade according to a fourth embodiment shown in FIG. 4 will be described. The blade shown in FIG. 4 also includes an outer skin 3 and an inner filler 4, and the outer skin 3 is further formed of a plurality of layers of a carbon fiber reinforced composite material portion 7 and a glass fiber reinforced composite material portion 8.

By adopting the structure of the composite material blade composed of the carbon fiber reinforced plastic composite material and the glass fiber reinforced plastic composite material as described above, the size and the size can be reduced.
Effects such as weight reduction or enlargement can be expected. The layer configuration, arrangement, and thickness of the carbon fiber reinforced composite material portion and the glass fiber reinforced composite material portion are arbitrarily determined according to the required characteristics of the blade.

Next, a description will be given of a specific experimental example of the structure of the actually fabricated blade according to the present embodiment and its constituent materials. As materials, matrix resin is epoxy resin, glass fiber is plain weave roving cloth (320
g / m ² ) and glass chop (fiber length: 2-3 cm)
The carbon fiber is a plain weave roving cloth (200g
/ M ² ).

The glass fiber strand used is E glass, has a tensile strength of 250 to 300 kgf / mm ² and an elastic modulus of 7,500 kgf / mm ² . The carbon fiber is a PAN fiber and has a tensile strength of 350 to 400.
kgf / mm ² , elastic modulus is 24,000 kgf / mm ²
It is.

The outer skin 3 extending from the wing portion 1 to the blade root flange portion 2 has strength and strength on the wing surface layer where the stress generated during operation is large.
A plain weave roving cloth made of carbon fiber having excellent rigidity was layered, and the necessary number of plain weave roving cloths were continuously laminated on the inner layer from the blade part 1 to the blade root flange part 2. The internal filler 4 was filled with a glass chop material.

The carbon fiber cloth material used for the surface layer of the outer cover 3 and having excellent strength and rigidity has a lower density than the glass fiber cloth material (density of glass fiber: 2.
6 g / cm ³ , density of carbon fiber: 1.8 g / c
m ³ ), the effect of weight reduction can also be expected, but since the material cost is high, it is basically desirable to use it in the minimum necessary amount.

The method for manufacturing the blade is as follows: a molding die is filled with glass fibers and carbon fibers in required amounts in a predetermined form;
After that, a method of injecting an epoxy resin was performed until the resin was injected at room temperature until the resin was cured to a certain degree, and then heated and cured at a high temperature of 100 to 120 ° C. to obtain a composite material blade. In addition, the manufactured composite material blade was subjected to a property confirmation test by cutting investigation, and it was confirmed that there was no defect such as an unfilled portion of the resin, and that the lamination interface between the carbon fiber cloth material and the glass fiber cloth material was also good. .

The blade according to this embodiment, in addition to the effect of the composite material blade of the previous embodiment, can further reduce the thickness and size of the entire blade by improving the material strength. In addition, a larger and lighter composite blade can be manufactured, and a significant improvement in the performance of the axial fan can be expected.

(Fifth Embodiment) Next, a blade according to a fifth embodiment shown in FIG. 5 will be described. The blade according to the present embodiment includes a wing portion 1 made of a fiber-reinforced plastic composite material and a metal mounting jig 12 embedded in the wing portion. The wing portion is composed of an outer skin 3 and an inner filler 4.

The wing portion 1 is made of a fiber-reinforced plastic composite material, and has a structure in which a metal mounting jig 12 for fixing the wing to the rotor shaft is embedded in the wing. The fixing of the mounting jig 12 to the inside of the wing is performed by a method of embedding the wing portion with an integrally molded structure at the time of manufacturing the wing portion or a method of performing a joining process after the wing portion is manufactured.

The shape and number of the mounting jigs 12 differ depending on the shape of the blade, the generated stress and the like. Examples are listed below. a) One or a plurality of rods (square, round, oval) or hollow pipes are used. b) The buried portion inside the wing is divided into two or more rods. c) A buried portion in the inside of the wing is used in a tapered shape. d) The buried portion in the wing is provided with a protrusion for the purpose of preventing pull-out.

Next, the structure of the composite material blade according to the present embodiment, which was actually manufactured, and specific experimental examples of its constituent materials will be described. As materials, epoxy resin as matrix resin, plain weave roving cloth (320 g / m ² ) as glass fiber and glass chop (fiber length:
2-3 cm) was used. The outer skin 3 of the wing portion 1 was a laminate of a plain weave roving cloth, and the inner filler 4 was a glass chop material.

The blade is manufactured by filling a wing mold with a required amount of glass fiber in a predetermined amount, at the same time disposing a metal (chromium-molybdenum steel) mounting jig 12 and then using an epoxy resin. After injecting resin at room temperature and curing to some extent,
The composition was cured by heating at a high temperature of ℃ to obtain a composite material blade made of a glass fiber reinforced plastic composite material.

The mounting jig 12 in this experimental example is
One rod-shaped jig was used, and the embedded portion inside the blade was provided with a taper for the purpose of preventing pull-out, and the mounting portion to the rotor (rotor) shaft was a screw-tight structure.

In order to confirm the strength and the state of breakage of the manufactured blade, a jig 12 was fixed to a tensile tester, and a tensile test was performed in which the blade was pulled. As a result, even with an additional force three times the required strength, no cracks were observed in any of the wing portions and the wing attachment portions, and it was confirmed that application to products was sufficiently possible.

(Sixth Embodiment) Next, a blade according to a sixth embodiment shown in FIG. 6 will be described. The blade according to the present embodiment includes a wing portion 1 made of a fiber reinforced plastic composite material and a mounting jig 22 made of a carbon fiber reinforced composite material embedded in the wing portion. The wing portion is composed of an outer skin 3 and an inner filler 4.

The fixing of the mounting jig 22 to the inside of the wing is performed by a method of embedding the wing with an integrally molded structure at the time of manufacturing the wing, or a method of performing a joining process after the wing is manufactured.

The shape and number of the mounting jigs 22 differ depending on the shape of the blade, the generated stress, and the like. Examples are listed below. a) One or a plurality of rods (square, round, oval) or hollow pipes are used. b) The buried portion inside the wing is divided into two or more rods. c) A buried portion in the inside of the wing is used in a tapered shape. d) The buried portion in the wing is provided with a protrusion for the purpose of preventing pull-out.

Next, a description will be given of the structure of the composite material blade according to the present embodiment, which was actually produced, and a specific experimental example of its constituent materials. Epoxy resin was used as a matrix resin, and plain woven roving cloth (320 g / m ² ) and glass chop (fiber length: 2 to 3 cm) were used as glass fibers. The outer skin 3 of the wing portion 1 was a laminate of a plain weave roving cloth, and the inner filler 4 was a glass chop material.

The mounting jig 22 is pulled with PAN-based fiber.
Strength is 350-400kgf / mm ^Two, The elastic modulus is 24,
000kgf / mm^TwoCarbon fiber, epoxy resin
And formed into a pipe shape (tip divided into two parts)
A carbon fiber reinforced composite material was used. In addition, buried inside the wing
At the tip of the part to be embedded (two-part structure),
A large diameter part was provided for the purpose.

The method of manufacturing the blade is as follows: a wing mold is filled with a required amount of glass fiber in a required amount, and at the same time, a mounting jig 22 made of a carbon fiber reinforced composite material which has been manufactured in advance is arranged. After that, a method of injecting an epoxy resin was performed until the resin was injected at room temperature until the resin was hardened to a certain degree.

In order to confirm the strength and the state of breakage of the manufactured blade, a jig 22 was fixed to a tensile tester, and a tensile test was performed in which the blade was pulled. As a result, even with an additional force three times the required strength, no cracks were observed in any of the wing portions and the wing attachment portions, and it was confirmed that application to products was sufficiently possible.

Since the mounting jig made of carbon fiber reinforced composite material is used in the blade according to the present embodiment, it is much larger than the composite blade having the metal mounting jig structure in the fifth embodiment. Lightening is possible.

(Seventh Embodiment) Next, a blade according to a seventh embodiment shown in FIG. 7 will be described. The blade 1 of the blade shown in FIG. 7 is made of a fiber-reinforced plastic composite material, and a part (in this case, the leading edge of the blade) has a thin metal plate 9.
(In this case, made of SUS304).

The thin metal plate 9 is provided to improve the wear resistance and erosion resistance of the wing portion and to improve the durability (extend the life). For this purpose, the thin metal plate 9 is mainly attached to the leading edge of the wing. You. However, in some cases, it may be attached to the entire wing surface.

The method of attaching the thin metal plate 9 includes a method of integrally molding and incorporating at the same time when the composite material blade is manufactured, a method of mechanically attaching the composite material blade (for example, attaching with screws), and a method of attaching the composite material blade with an adhesive. There is a method of bonding or a method of using both mechanical bonding and adhesive bonding.

The thickness of the metal sheet 9 is not particularly limited.
The thickness is determined so that the effects of wear resistance and erosion resistance can be obtained.

Next, the structure of a composite material blade according to the present embodiment, which is actually manufactured, and specific examples of constituent materials thereof will be described. Epoxy resin was used as a matrix resin, and plain woven roving cloth (320 g / m ² ) and glass chop (fiber length: 2 to 3 cm) were used as glass fibers. The outer skin 3 of the wing portion 1 was a laminate of a plain weave roving cloth, and the inner filler 4 was a glass chop material.

A method of manufacturing a composite material blade is a method in which a required amount of glass fiber in a predetermined form is filled in a mold of a wing, and then epoxy resin is injected. At a high temperature of 100 to 120 ° C. to obtain a composite blade made of a glass fiber reinforced plastic composite material.

Next, a thin plate made of SUS304 (width 30 × length 300 × plate thickness 0.5 mm) 9 is bent so as to conform to the shape of the leading edge of the blade, and attached with an epoxy resin adhesive.
Six more places (three ventral and three dorsal) are SUS30
Fastened with four screws. The blade according to this embodiment has further improved wear resistance and erosion resistance.

Eighth Embodiment Finally, a blade according to an eighth embodiment shown in FIG. 8 will be described. FIG.
The blade 1 of the blade shown in (1) is made of a fiber-reinforced plastic composite material and has excellent wear resistance and erosion resistance that can be easily applied (applied or adhered) to a part (in this case, the leading edge of the blade). And a composite blade in which the polymer coating material 10 is disposed.

The polymer-based coating material 10 has a wing abrasion resistance,
It is provided to improve erosion resistance and durability (extend service life), and is mainly applied to the leading edge of the wing for that purpose. However, in some cases, construction may be performed on the entire wing surface.

The application of the polymer-based coating material 10 is desirably a coating method or a bonding method that can be easily applied after the production of the composite material blade, and in some cases, a method that can cope with repair.

Examples of the polymer coating material 10 having excellent wear resistance and erosion resistance include a rubber material, a fluororesin or a plastic containing glass flakes, and a plastic material containing ceramic particles or metal particles.

Next, a description will be given of a specific example of the structure of the blade according to the present embodiment, which was actually manufactured, and its constituent materials. The wing body is made of epoxy resin as matrix resin, plain woven roving cloth (320 g / m ² ) as glass fiber and glass chop (fiber length: 2).
３3 cm) was used. The outer skin 3 of the wing portion 1 was a laminate of a plain weave roving cloth, and the inner filler 4 was a glass chop material.

A method of manufacturing a composite material blade is a method in which a required amount of glass fiber of a predetermined form is filled in a molding die of a wing, and then an epoxy resin is injected. At a high temperature of 100 to 120 ° C. to obtain a composite blade made of a glass fiber reinforced plastic composite material.

Next, 20% by volume of glass flakes was mixed with an epoxy resin having the highest adhesive strength among the polymer materials, and the mixture was mixed with the epoxy resin.
mm, abdominal width 15 mm). The same construction method is applied to other polymer coating materials.

[0084]

As described above, the blade of the axial flow fan according to the present invention is a blade of an axial flow fan comprising a blade portion and a blade root flange portion, wherein the blade portion and the blade root flange portion are made of glass fiber. The following effects are obtained by integrally forming a fiber-reinforced plastic composite material such as a reinforced plastic composite material or a carbon fiber reinforced plastic composite material.

That is, according to this structure, the weight of the blade can be greatly reduced, so that the entire axial flow fan device can be reduced in size, size and weight. Accordingly, the responsiveness at the start of the fan is improved, and the power consumption can be reduced. If necessary, the number of rotations of the rotor can be increased, and a significant performance improvement of the fan can be expected.

Further, the structure of the variable pitch mechanism for rotating the blade by a hydraulic device via a mechanism such as a gear can be simplified and downsized, and a significant cost reduction of the entire axial flow fan can be achieved.

The present invention also provides, in addition to the above-described configuration, means for attaching a blade to a rotor, such as a metal bolt, a metal nut, or a metal flat plate, for a blade root flange portion. I do.

According to this blade structure, in addition to the effects described above, the structural strength of the blade root flange is further improved, so that the structure can be made compact, such as thinner and smaller. In particular, if the mounting means is embedded and integrally molded at the time of blade manufacturing, the manufacturing cost is reduced since the fiber-reinforced plastic composite material at the blade root flange for mounting the blade to the rotor does not require holes such as screws. It is possible.

Further, in addition to the above-described structure, the blade of the axial flow fan according to the present invention has a structure in which a thin metal plate or a polymer-based coating material is adhered to at least a part of the blade surface. A composite blade having good abrasion resistance and erosion resistance and excellent durability can be obtained.

In the blade of the axial flow fan of the present invention, a mounting jig made of metal or carbon fiber reinforced composite material directly integrated with the blade is provided instead of the blade root flange. In the case of the structure, the blade structure is further simplified, the manufacturing process is simplified, and the cost reduction is further promoted.

[Brief description of the drawings]

1A and 1B are drawings showing a blade of an axial fan according to a first embodiment of the present invention, in which FIG. 1A is a plan view in which a wing portion is a cross-sectional view, and FIG.

FIGS. 2A and 2B are drawings showing a blade of an axial fan according to a second embodiment of the present invention, wherein FIG. 2A is a plan view in which the wing portion is a cross-sectional view, and FIG.

FIGS. 3A and 3B are drawings showing a blade of an axial flow fan according to a third embodiment of the present invention, wherein FIG. 3A is a plan view in which the wing is a cross-sectional view, and FIG.

FIG. 4 is a partially enlarged plan view showing a blade section of a blade of an axial fan according to a fourth embodiment of the present invention.

FIGS. 5A and 5B are drawings showing a blade of an axial flow fan according to a fifth embodiment of the present invention, wherein FIG. 5A is a plan view in which the wing is a cross-sectional view, and FIG.

FIGS. 6A and 6B are drawings showing a blade of an axial fan according to a sixth embodiment of the present invention, wherein FIG. 6A is a plan view in which the wings are cross-sectional views, and FIG.

FIGS. 7A and 7B are drawings showing a blade of an axial fan according to a seventh embodiment of the present invention, in which FIG. 7A is a plan view in which a wing portion is a cross-sectional view, and FIG.

FIGS. 8A and 8B are drawings showing a blade of an axial flow fan according to an eighth embodiment of the present invention, wherein FIG. 8A is a plan view in which the wing portion is a cross-sectional view, and FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wing part 2 Wing root flange part 3 Outer skin 4 Internal filler 5 Metal bolt 6 Adhesive 7 Carbon fiber reinforced composite material 8 Glass fiber reinforced composite material 9 Metal thin plate 10 Polymer coating material 12 Metal mounting jig 15 Metal nut 22 Mounting jig made of carbon fiber reinforced composite material 25 Metal flat plate

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[Procedure amendment]

[Submission date] October 13, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

[Correction contents]

The outer skin 3 extending from the wing portion 1 to the blade root flange portion 2 has strength and strength on the wing surface layer where the stress generated during operation is large.
Plain woven roving cloth of carbon fiber with excellent rigidity is layered, and the necessary number of glass fiber plain woven roving cloths are continuously laminated on the inner layer from wing part 1 to wing root flange part 2. did. The internal filler 4 was filled with a glass chop material.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08K 7:06 7:14) (72) Inventor Masanori Koga 1-1, Akunoura-cho, Nagasaki-shi, Nagasaki Shipyard, Mitsubishi Heavy Industries, Ltd.

Claims (8)

[Claims] 1. A blade for an axial flow fan comprising a blade portion and a blade root flange portion, wherein the blade portion and the blade portion flange portion are integrally formed of a fiber-reinforced plastic composite material. Fan blade. 2. The blade for an axial fan according to claim 1, wherein the wing portion comprises an outer cover made of a fiber-reinforced plastic composite material and an inner filler filled in the outer cover. . 3. The fiber reinforced plastic composite material according to claim 1, wherein one or both of a glass fiber reinforced plastic composite material and a carbon fiber reinforced plastic composite material are laminated. Axial fan blades. 4. A blade for an axial fan according to claim 1, wherein a means for attaching the blade to the rotor is provided on the blade flange. 5. The blade for an axial fan according to claim 4, wherein the means for attaching the blade to the rotor is a metal bolt, a metal nut, or a metal flat plate embedded in a blade root flange. . 6. A blade for an axial fan according to claim 1, wherein a thin metal plate or a polymer-based coating material is attached to at least a part of the surface of the wing portion. 7. The blade of an axial fan according to claim 1, wherein a mounting jig directly integrated with the blade is provided in place of the blade root flange. 8. The blade according to claim 7, wherein the mounting jig is made of metal or carbon fiber reinforced composite material.