JPS6323040B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a method for manufacturing rotor blades, and in particular aerodynamic rotor blade assemblies such as helicopter rotor blades.

[Explanation of Terms] The main terms used in this specification will be explained.

a "Composite girder members" Currently, the girder members of helicopter rotor blade assemblies (load-bearing structural members elongated in the span direction that mainly bear aerodynamic loads) are usually made from composite materials in order to be lightweight and strong. be done. The word "composite" is also used to mean "simply joining two or more members together," but in this specification it refers to "a spar made of composite material."

b “Aft fairing structure” This term is not often used by those skilled in the art in Japan, but its original meaning is “Aft fairing structure”.
"Fairing" is commonly used as "straightening material" or "shaping material", so it means "the part that straightens the airflow behind the girder member", and in this specification, it is used as "core part, composite girder rear end member". and a rear rectifying structure consisting of upper and lower outer panels.

c. "Core" means "lightweight core, preferably made of foam or honeycomb", so-called "honeycomb core".

d "Lay-up""Lay-up" is defined as "placing reinforcing material such as resin-impregnated glass fiber in a mold." Then, a reinforcing material such as glass fiber impregnated with resin to be hardened later by heat is placed in the mold,
The premise is that the laid-up members will be firmly bonded to other members by being subjected to heat and pressure in an uncured state.

e Subassemblies The aerodynamic rotor blade assembly is finally assembled by combining the individually manufactured subassemblies. This term is used because this "subassembly" is a product unit that is either manufactured in-house or procured from another company. The aforementioned "rear rectification structure" is also one of the sub-assemblies.

f The following two main assembly jigs are used in the present invention.
It is one.

"Adhesive assembly jig": A jig for assembling the rear rectifier structure. "Single assembly mold": A jig for performing final assembly using each subassembly.

BACKGROUND OF THE INVENTION Since the advent of composite rotor blades, there has been a continuing desire in the industry to reduce manufacturing costs by reducing or modifying the manufacturing process. However, the fabrication of composite rotor blades is still produced by combining a number of individually fabricated subassemblies. Most of them are sub-assemblies that have undergone multiple curing processes,
Each major subassembly requires a separate adhesive assembly jig.

Conventional methods of manufacturing such composite rotor blades include, for example, the following subassemblies and final assemblies:

1. Cap material, deicing blanket, and front end block subassemblies.

2-digit subassembly.

3. Subassembly of spar and cap material, de-icing blanket, and front end block.

4 Trailing edge wedge subassembly.

5 Core sub-assembly of rear rectifier structure (without machining) with one skin.

6 Core subassembly of (machined) rear rectifier structure with both skins.

7 Final assembly including subassemblies 3 to 6 above.

As readily understood above, this final assembly requires at least seven curing or bonding steps. Blade manufacturing that involves many curing and bonding steps is inevitably expensive, and this alone is undesirable.

Therefore, it would be desirable to reduce the overall number of curing and bonding steps currently required to manufacture such composite rotor blades, resulting in lower manufacturing costs, while not adversely affecting the structural integrity of the blade.

Of the various subassemblies mentioned above, it is the girder subassembly that poses the greatest barrier to manufacturing economy and optimum structural integrity. for example,
One of the previously known methods using a curing step involves
Back pressure had to be applied to the exterior surface of the spar to counteract the internal bag pressure acting inside the spar during the curing process to avoid structural damage.

The only conventional method suitable for this was to fabricate the spars separately in one mold. As an example of this, Japanese Unexamined Patent Application Publication No. 16298/1983 discloses three girder constituent parts 1 as shown in FIG. 9 attached to this specification.
12, 113, and 114 by overlapping joints to form an approximately D-shaped hollow composite girder member 12', a trailing edge portion 103 is joined to its rear surface, and a skin plate 28', A front end block 18' is inserted between components 113 and 114 of the spar member 12' near the leading edge, and a deicing blanket 122 is placed on the leading edge surface of the component 114. A rotor blade assembly is disclosed in which a rotor blade assembly and a cap member 16' are mounted and pressure-coupled. In this case, the three component parts 112, 113, and 114 of the spar member 12' are separately made into a D-shaped final shape using a mold, and then the rear surface of the spar member 12' is The trailing edge 103 is joined to the outer plate 28',
The final rotor blade assembly could not be completed without a method of pressurizing the parts 30' together.

In another conventional manufacturing method that uses a curing process, the spar back end material is made separately from the spar, and the spar back end material is assembled to the spar during the spar hardening process. However, this method is not satisfactory. One of the reasons for this was that the spars developed undesirable surface wrinkles, which resulted in poor surface adhesion to other parts of the blade and thus impeded load transfer.

[Problem to be solved by the invention] Although the girder is a major element of the rotor blade, it has hitherto had to be manufactured separately for at least the reasons mentioned above, and it has not been possible to complete it. It is clear that streamlining of fabrication could be achieved if a method were perfected that would eliminate the need to fabricate the girder as a separate subassembly.

Thus, it would be desirable to have a method for making composite rotor blades that does not require separate assembly of the completed spar and does not create any conditions that would prevent the spar from working properly.

Therefore, one of the objects of the present invention is to develop a composite structure, preferably an aerodynamic rotor blade assembly, which can be assembled in fewer steps than conventional rotor blade assemblies and which has superior structural integrity. It is an object of the present invention to provide a method for manufacturing an aerodynamic rotor blade assembly that can be completed into a blade.

It is a further object of the present invention to provide a method for the above-mentioned purpose, which does not cause the structural integrity of the composite structure to be worse than that of conventional methods. It is an object of the present invention to provide a method in which the structural integrity of an aerodynamic rotor blade assembly made by such a method is maintained without any loss.

Another object of the present invention is to provide a method for the above-mentioned purpose, in which the U-shaped girder rear end material is separately manufactured, and then incorporated as a component of the rear rectifying structure, and then the separately manufactured girder rear end material is assembled. It is an object of the present invention to provide a method characterized by fitting into a D-shaped composite girder member (hereinafter abbreviated as girder).

Still another object of the invention is to provide a method for the above-mentioned purpose, in which at least some of the subassemblies mentioned in the description of the prior art are rendered useless. It is to be.

Another object of the invention is to provide a method for the aforementioned purpose, in which the final assembly of the composite structure is performed using a single assembly mold.

Another object of the present invention is to provide a method for manufacturing an aerodynamic rotor blade assembly for the above-mentioned purpose, in which the skin of the rear rectification structure and the deicing blanket structure have excellent effects as load-bearing structural members. The purpose is to provide a method of manufacturing something that is designed to exhibit the desired performance.

A still further object of the present invention is to provide a method for manufacturing an aerodynamic rotor blade assembly for the above-mentioned purpose, wherein the base of the rotor blade comprises a D-shaped spar, a cap material, and a U-shaped spar rear end. The purpose of the present invention is to provide a manufacturing method for objects formed from parts and materials.

[Means for Solving the Problems] In order to solve the above problems, the characteristic configuration of the first aerodynamic rotor blade assembly manufacturing method according to the present invention is as follows: (a) the assembly forms the leading edge of the blade; (b) a front end block having a girder engaging surface; (c) (d) A girder with an outer surface having a blade root and a girder rear end material engagement part; (e) A girder that forms the trailing edge of the blade and has an upper surface, a lower surface, a front surface, and a rear surface. and a rear rectifying structure comprising a lightweight core whose upper and lower surfaces are contours of desired portions of an airfoil shape, and outer plates fixed to the upper and lower surfaces of the core, respectively; f) a wing tip cover having a surface that engages with the cap material and both outer plates; A manufacturing process comprising the following steps: (i) attaching outer panels to each of the upper and lower surfaces of the core with adhesive; (ii) attaching the girders to the front surface of the core and each of the outer panels; a step of attaching the trailing edge material with adhesive; (iii) a step of fixing each of the attachment surfaces to each other by applying heat and pressure to the adhesion assembly jig; (b) the following (i)-- arranging the spar, the cap material, the front end block, the rear straightening structure, and the wing tip cover in a single assembly mold in the state of (v), (i) the front end block engaging portion on the inner surface of the cap material; The girder engaging part and the rear rectifying skin engaging part are
(ii) a spar engaging surface of the front end block engages the spar; (iii) a spar rear surface of the outer surface of the spar; (iv) the surface of the wing tip cover engages with the cap material and both outer plates; (v) (i) - (iv) each of the engaging surfaces is attached by an adhesive; (c) said attachment surfaces are secured together by applying heat and pressure within said single assembly mold; , the process of creating an aerodynamic rotor blade assembly.

Furthermore, a characteristic feature of the method for manufacturing a second aerodynamic rotor blade assembly according to the present invention is that the assembly includes: (a) an outer surface forming the leading edge of the blade, a front end block engaging portion, a spar engaging portion and a rear portion; A cap material having an inner surface having a rectifying skin plate engagement portion, (C) a front end block having a U-shaped girder engagement surface, (C) a U-shaped girder rear end member, and (C) a U-shaped girder rear end member; ) a spar having an outer surface having a blade root and a spar trailing edge engagement portion; a rear rectifying structure comprising a lightweight core contouring a desired portion of the shape and outer panels affixed to upper and lower surfaces of the core, respectively, and (f) said cap material and both outer panels; and a wing tip cover having an engaging surface, and the manufacturing method comprises the following steps: (a) a step of manufacturing the rear rectifying structure in an adhesive assembly jig, which includes the following steps: (i) laying up one of the outer panels in the jig and engaging the laid-up outer panel with the lower surface of the core; (ii) laying the other of the outer panels together in the jig; (iii) engaging the rear end of the girder with each of the laid-up outer panels and applying adhesive to the core; (iv) Applying heat and pressure to each of the laid-up skin panels in a curing process to finish them into structural members, and at the same time, The process of fixing the engaged surfaces of.

(b) a step of arranging the spar, cap material, front end block, rear straightening structure, and wing tip cover in a single assembly mold in the following states (i) to (v); (i) the cap material; The front end block engagement part, the spar engagement part and the rear rectifying skin engagement part on the inner surface are
(ii) a spar-engaging surface of the front end block engages the spar; (iii) a spar rear end of the outer surface of the spar; (iv) the surface of the wing tip cover engages with the cap material and both outer plates; (v) the above (i) to ( Each of the engaging surfaces of iv) is attached by adhesive.

(c) bonding the mounting surfaces together by applying heat and pressure within the single assembly mold to create an aerodynamic rotor blade assembly;

The effects of the present invention will be explained below.

[Function/Effect] (1) The above purpose is to assemble and join many parts such as girder, cap material, front end block, girder rear end material, core, outer plate, etc. to produce a bulky whole. Despite the high overall bulk, this is achieved by heating and pressurizing the entirety of these multiple assemblies in a single mold. By using this method, even though the product is made up of many parts and is bulky, the entire outer shape can be finished accurately. In other words, when manufacturing rotor blade assemblies, which are strictly required to accurately finish extremely delicate external shapes, it has become possible to easily and accurately achieve this objective.

In particular, when the rear end of the spar of the composite rotor blade is formed into a U-shape and formed as part of the rear rectifying structure, the following effects are produced.

That is, this eliminates from the manufacturing process, for example, the need to manufacture three separate subassemblies: the cap and leading block; the spars; and the spars, caps, and leading blocks. be done. As such, the rear rectification structure including the spar rear end can withstand the bag pressure acting inside the spar rear end during its assembly due to the rigidity of the U-shaped spar rear end, and the formation There is no need to apply back pressure from the mold. Therefore, a single assembly mold can be used within which the cap material, leading end block, and spar can be included as assembled elements along with the rear baffle structure to subsequently mold the composite blade. , or they could be used as various subassemblies with rear baffle structures to form composite blades.

By doing this, the outer panels of the rear rectifier structure can be fixed in a fail-safe manner, and such outer panels can be ensured to perform excellently as load-bearing structural members.

(2) Additionally, the U-shaped spar trailing end of the blade assembly with the outer surface of the cap material, both attached skin plates, and the spar trailing material being received within the recess between the cap material and the spar. the inner surface of the spar inside the timber area, i.e. the outermost layer of cap material, the next layer of skin, the layer of spar trailing material inside that, and the innermost D-shaped A spanwise continuous, extremely strong wall is completed in which four of the girder layers are bonded together. This wall can withstand shear forces along the fore-and-aft surface of the rotor blade airfoil profile for extremely efficient load transfer, and at the same time can withstand shear forces along this wall in the spanwise direction of the rotor blade. Load transfer can be carried out very effectively, and the spanwise bending and torsional strength of the rotor blade assembly can be sufficiently withstood. Therefore, it can be assembled together with the rear rectifying structure and the cap material to form a fail-safe structure by firmly adhering to the rear rectifying structure, improving the load transmission from the girder to the rear rectifying structure, and increasing the load-bearing capacity of the rotor blade itself. It is.

Moreover, this concave part has the remarkable effect of making the surface shape smooth by using a mold with a smooth inner surface, and by overlapping and connecting both end faces of the membrane-like structure on the outer surface. In the recess, the girder rear end material and the girder, as well as the girder rear end material and the outer panel of the rear rectification structure, are strongly connected to each other by resisting the tensile force along the tangential direction by "utilizing the locking effect at the step". There is a significant advantage in that they can be combined.

(3) As one of the broader features of this invention to achieve that purpose, after separately manufacturing the rear rectifying structure, the manufactured rear rectifying structure is assembled into girders, cap materials, etc. for final assembly. One method is to place the leading end block and tip counterweight mounting structure in a single assembly mold. It is also possible, if desired, to first procure each individual component of the composite structure and then construct the rear baffle structure and then secure the various engagement and attachment surfaces of each component.
Final assembly can also be done using adhesive.

If desired, some of these components may be procured and the remaining components fabricated during formation of the rear baffle structure and final assembly.

(4) It is also possible, and indeed preferred, to build up most of the components from materials capable of curing during the formation of the rear baffle structure and final assembly.

(5) In particular, in the method of manufacturing the aerodynamic rotor blade assembly according to the second invention, in the step of creating the rear rectifying structure in the adhesive assembly jig of paragraph (a), the method of manufacturing the aerodynamic rotor blade assembly according to the second invention requires fixing to both the upper and lower surfaces of the core. After laying up both skins, they are engaged with the core and applied heat and pressure in a jig, and then placed in a single assembly mold and heat and pressure applied to the whole. Since it is finished into a structural member, it has the following effects.

In other words, a flexible composite skin material made of fiber fabric impregnated with a thermosetting resin is laid up in a mold, a core is aligned with it, and the material is molded using heat and pressure. Despite being bulky due to the external force of the mold, the resin-impregnated fibers, which are flexible, conform to the shape of the mold, forming a precise and precise shape. Since it is given, it can be finished precisely and precisely, and it becomes a powerful structural method. This strength is achieved not only by the synthetic resin that functions as an adhesive being cured by heat, but also by the composite structure of the cured resin and fiber material. As a result, a strong structure with a strictly correct external shape can be obtained. In addition, in combination with the first invention, a remarkable advantage has been obtained in that all the rotor blades can be made precisely, precisely, and powerfully.

Not only is the large-area outer panel made of reinforced composite material, but the large-area reinforcement material is pre-impregnated with a thermosetting resin for bonding, resulting in a single mold. When placed within and formed,
By applying heat while being wrapped in a single mold for molding and under pressure, it is firmly joined at once in the correct posture to fit the mold, making it extremely easy to operate and maintaining the finished dimensions. This method has the advantage of being extremely accurate and reliable.

In detail, the resin impregnated in the reinforcing material bonds the outer panel made of this reinforcing material and the core, so even if the outer panel is thin, the entire outer panel is attached to the core. This will create a strong bond between the two.

In this way, the finished state after assembly is much better than when adhesive is applied to each member and then bonded. In other words, the dimensions of each part, such as the core and both outer panels, are not necessarily accurate, and when the finished parts are stacked on the outer panel, these parts fit together with high precision. Although contact may not always occur, even if such a situation occurs, according to the lay-up method, the contact parts of each part have adhesive properties, so it is easy to assemble within a single mold. In this case, dimensional flexibility is exhibited, resulting in excellent finishing accuracy. Therefore, when the resin portion is cured by heating and pressurizing in a single mold in a post-process, the overall shape and dimensions can be made accurate and the finished appearance can be made beautiful.

[Example] Next, an example of the present invention will be described in detail based on the drawings.

First, the details of the composite blade 10 according to the present invention are shown in Figures 1 and 2.

The composite blade 10 has, as its main part,
D-shaped spar 12, rear baffle structure 14, cap material 16, front end block 18, and wing tip cover 20
including.

The girder 12 is formed as a substantially D-shaped cross-sectional structure with rounded corners extending in the span direction to a substantially rectangular base 22. This spar 12 was hollow and cylindrical and served as the main load-bearing member of the blade, so that all the other components would work together to make up the composite structure of the blade. It is assembled and supported by this. As such a supporting spar, its outer surface is shaped to house the other components of the blade and to give the blade an airfoil cross-section.

A major feature of this invention is that the rear part of the spar is made as a separate member 24, which is capable of handling not only the operational flight loads of the helicopter, but also each hardening step that is applied to this member, if a hardening step is included. It can withstand extreme temperature and pressure conditions.

According to this invention, the U-shaped girder rear end material 24
is first secured to the aft baffle structure 14 and then attached to the spar 12 as part of the aft baffle structure.

The spar trailing end member 24 has a generally U-shaped cross section, but is extended in the span direction and is shaped to fit the spar in order to form the root portion 22 of the blade.

Rear rectification structure 14 excluding this girder rear end material 24
typically includes a lightweight core 26, preferably made of foam or honeycomb, and a top skin 28.
, a lower skin 30 , and in most cases also a trailing edge wedge 32 .

Preferably, each of these components of the rear baffle structure is of continuous construction over the entire span. However, each of these components could also be any suitable number of separate box structures 34, each including a core, a top skin, a bottom skin, and in most cases also a trailing edge wedge. In the assembled state, the box structures are separated by partition ribs 36 (only schematically shown in FIG. 1).
These partitioning ribs 36 are preferably made of rubber.

Preferably, the rear rectifying structure 14 is balanced after being assembled to the spar rear end member 24. For that purpose, the spar back end 24 is provided with an extension as a housing 38 for housing the counterweight added during the balancing process. The process itself is well known and does not require detailed explanation. As seen in FIG. 1, the tip of the blade 10 is closed with a wing tip cover 20.

At the front end of this blade, in addition to the cap material 16 and the front end block 18, there is also a deicing blanket 4.
It is preferable to also include 0. Note that there is a through hole 42 extending in the span direction in the front end block 18, into which a counterweight (not shown) is inserted.

The cap material 16 is preferably made of a metal such as titanium, but any non-metallic material may be used as long as it can prevent corrosion. Regardless of whether the main body of the cap material 16 is made of metal or non-metal, there is a non-metal part in the inner part,
It, together with the spar 12 and the U-shaped spar rear end member 24, forms the root of the blade. A blade torsion splice (not shown) is formed at its root.
The process of making blade torsion splices is well known, so a detailed explanation will be omitted.

Aspects determined by the various components described above are important to clarify in order to better understand the manufacture of this rotor blade assembly, and are discussed below.

The outer surface of the cap 16 defines the leading edge 44 of the blade, while its inner surface defines the leading end block engagement section 46, the spar engagement section 48, and the aft baffle skin engagement section 50. It is clear from FIG. 2 how widely each of these parts engages. If the blade incorporates a de-icing blanket, the leading end block engagement portion 46 would rather engage the de-icing blanket 40, as shown in FIG.

The front end block 18 has a spar engaging surface 51 that engages the spar 12.
has an outer surface provided with a spar rear end material engaging portion 52;
The core 26 of the rear rectifying structure 14 has front, rear, upper, and lower surfaces 54, 56, 58, and 60 formed thereon.
Additionally, the rear baffle structure 14 includes a trailing edge 76 of the blade.
form.

As seen in FIG. 2, in the blade assembly, the outer surface of the spars 12 along with the cap material 16 form a spanwise continuous recess 53 (FIG. 5).
Additionally, a slot 55 (a fifth
(Figure), respectively.

Having described the various components of this composite blade and their interrelationships, the manufacture of the rotor blade will now be described with reference to FIGS. 3-7. Of the various jigs and tools used during fabrication, these figures only show those to the extent necessary for understanding the invention.

In preparation for fabricating the rear baffle structure 14, the lower surface 60 of the core 26 is cut or machined by conventional methods to closely match the slope of the mating surface 62 of the adhesive assembly jig (see FIG. 3). ) The wall surface of the cell of this core is processed so as to be substantially parallel to the girder rear end material 24 when the outer panel is placed on the jig portion 62. Alternatively, a core 26 having a surface 60 that exactly matches the inclination of the jig portion 62 from the beginning may be used.

The adhesive assembly jig also includes a pressure block 64 with a rubber pad 66, as shown in FIG. These other parts of the adhesive assembly jig are not shown but are well known to those skilled in the art.

One of the features of this invention is that the lower skin 30 can be procured in the form of a hardened or unhardened plate. In any event, this skin is attached to face 60 of core 26 using a suitable conventional adhesive.
attached to. The adhesive is preferably applied to both opposing surfaces, and heat and pressure are applied to the adhered core and outer panel while they are still in this adhesive assembly jig, thereby fixing the opposing surfaces.

As a preferred example characteristic of the present invention, the outer panel 30 is first laid up (here, "layup" means reinforcing material such as resin-impregnated glass fibers) in a jig section 62 by placing it in a mold. After the core 26 is positioned as described above, the jig is assembled and the heat and pressure of the curing process is applied to the contents. As a result of the curing reaction, the laid-up skin is affixed to the core 26 and simultaneously fabricated into a structural member.

The method of laying up parts and then curing them to form parts is well known.
No need to explain in detail.

By any of the methods described above, the lower skin 3
0 is secured to the core lower surface 60, the upper surface 58 is machined to the desired profile surface 58'.
That is, this outer surface 58' forms the upper surface of the core into the desired airfoil shape.

Next, the top skin 28 is placed in another jig section 68 of the adhesive assembly jig, only a portion of which is shown in FIG.
Place. Next, as shown in FIG. 4, the girder rear end material 24 is placed, and as described above,
The machined core 26 and the lower skin 30 affixed to it are also placed into this jig, with the machined surface 58' facing the top skin 28 and both skins and the core following the U-shaped girder. They are adapted to engage with the offcuts 24, respectively. If a trailing edge wedge 32 is included, it may be assembled with a machined core 26 with a bottom skin 30 or, as shown in FIG. 4, with a top skin 28 and a bottom skin 30. The trailing edge wedge 32 is placed in this jig against the machined core 26 with a
6. This trailing edge wedge member 32 is inserted before the spar trailing end member 24 is inserted. With rear baffle structure 14 thus assembled, the remaining portions of the jig are coupled to jig portion 68 in preparation for beginning the fastening process. One such portion is the side portion 70, which includes a mandrel 72 and an inflatable bladder 74 extending into the recess forming the U-shaped spar back end 24.
The mandrel 72 is used to support the spar rear end material 24 during the fixing process, and the expansion bag 74 is used to obtain uniform bonding over the entire engagement surface.

As already mentioned, one of the features of this invention is that the skin 28 can also be procured in a hardened or unhardened state, and the trailing edge wedge 32 can also be hardened or unhardened in the desired shape. But that's fine.
In this case, the upper skin 28, the spar trailing edge 24, the machined core 26 with the lower skin 30, and the trailing edge wedge 32 are coated with a suitable adhesive on each corresponding surface. Heat and pressure are applied while the parts are placed in this adhesive assembly jig, and their respective corresponding surfaces are fixed.

As one preferable example characteristic of this invention, the upper outer plate 28 and the trailing edge wedge member 32 are first connected to the jig portion 6.
The machined core 26 and the back end material 24 of the girder, which are laid up in the 8 and to which the upper skin 28 is fixed, are positioned in the same manner as in the previous case, the jig is assembled, and the stored material is subjected to the hardening process. Some types of heat and pressure are applied. As a result of that curing reaction,
The laid-up top skin 28 and laid-up trailing edge wedge 32 are fabricated into a structural member at the same time that all engagement surfaces are secured.

However, in any case, the girder rear end material 2
4 is manufactured separately. When making it, it is preferable to first lay it up in a mold and then mold it by applying heat and pressure in the curing process.

Even if the rear baffle structure 14 consists of a separate box structure 34, the manufacturing method is basically the same as described above. The lower skin panels 30 are placed side by side within the jig and are fixed to each corresponding core lower surface and partition rib. At the same time, each engaging side surface between the core and the partitioning rib of each box structure is also fixed, and the other side surface of each partitioning rib is also fixed to the core side surface of the adjacent box structure. For reasons previously discussed, prior to performing this fixing step, the underside of each core or partition rib cut is cut or machined to closely match the slope of the jig section 62. Thereafter, the process of creating the rear baffle structure 14 proceeds as previously described. The core and partition ribs and both upper and lower skins of the trailing edge wedge are preferably laid up and hardened.

An alternative method to that described above, which is suitable for both of the above-mentioned cases, is to cut the core or the core and the partitioning ribs for the purpose of machining the upper surface to the required external surface. There is a method in which a simulated board is first assembled on the core or on the lower surface of the core and the partition rib. after that,
The simulated plate is removed and both the upper and lower skin plates, the spar trailing edge, and if necessary the trailing edge wedge are secured in accordance with the method described above.

In one preferred embodiment of this invention, both skin panels and the trailing edge wedge material are laid up, and all the engaging surfaces are fixed by curing, and at the same time, the structure is made into a structural member. There is something to do.

The simulated board material may be a material of an appropriate thickness and easy to handle.

As a further alternative to the method described above, it is also preferable to procure a core 26 whose both surfaces 58 and 60 have been processed into a desired external shape. In this case, as a preferable example characteristic of the present invention, the core 26, both outer plates 28, 30, the girder rear end member 24, and the rear edge wedge member 32 are assembled and arranged as shown in FIG. There is a method in which the engagement surfaces are simultaneously fixed using an adhesive and heat and pressure under predetermined conditions to create a rear rectification structure.

In one preferred embodiment of this invention, both skin panels and trailing edge wedge material are laid up during assembly together with the procured core and trailing edge material, and all engaging surfaces are fixed by curing. There are some that are made into structural members at the same time as they are made into structural members.

After the rear baffle structure 14 is created, it is assembled into the rotor blade 1 as shown in FIGS. 5-7.
A single assembly mold 78, 8 with other parts of 0
It is assembled with 0.82.

The blocks 18, girders 12, and deicing blankets 40 may be prefabricated or procured. These three members can also be made up into separate subassemblies. However, as an alternative, the cap 16, de-icing blanket 40, and front end block 18, or the cap 16, de-icing blanket 70, or the spars 12 and front end block 18 may each be made into separate subassemblies. can.

However, the preferred method is that the leading end block 18 and spars 12 are laid up in the same manner as the trailing spar ends 24, the skins 28, 30, and the trailing edge wedges 32 in a single assembly mold. It is built up into a structural member during the final curing process. The front end block 18 is laid up directly on the cap material 16,
The spars 12 are also laid up on an inflatable, preferably rigid, mandrel 92 and placed in this state into the cap 16. When laying up the front end block, the balance weight can be included as a part, or if the front end block is already manufactured and procured, the front end block can be fitted into the cap material 16. A counterbalanced weight may be inserted into the through hole 42 beforehand.

For final assembly, the front end block 18, spars 12 and deicing blanket 4 are assembled as previously described.
0 and cap material 16 are placed in the front portion 78 of a single assembly mold and positioned using leading edge jig knobs 84. If a metal or non-metallic cap material 16 is used, it is preferable to use a spreading tool 86 with latches 88 and 90. Spread the cap material sufficiently with the holes 88 and 90 and attach it to the front end block 18 and the girder 12, or to the front end block 18 and the deicing blanket 40.
The spar 12 and the cap material are inserted into each other, and the rear rectifying structure with the spar trailing end member 24 can be properly engaged with the cap material 16 and the spar 12 for assembly.

Thus, once the blade has been assembled and positioned snugly against the front section 78 of the single assembled mold, the front section 78 can be removed by suitable means (not shown). pin 9
4 through the position shown in FIG. 6 to the position shown in FIG. 7, thereby:
The rear baffle structure 14 and a portion of the spars rest within the rear portion 80 of this single assembly mold. A positioning support 96 and a support plate 97 are provided to partially support the assembled blade during rotation of the front section 78 and to properly position the rear section 80. This positioning support 96 consists of one arm 98 and a two-part receiver 100 that receives the ends of the joined skin panels 28, 30 and can be fixed to each other by means not shown in the drawings. It is what it is. This arm 98 and receiver 100 are mutually rotatable.

The ends of both plates are intentionally shaped as shown in FIGS. 3-7. The reason is,
The blade can be safely pivoted with the front section 78 of the mold so that during assembly of any of the subassemblies previously described with the rear baffle structure shown in FIG. This is so that they can be firmly supported. All of the means for assembling the rear rectifying structure into the assembly shown in FIG. 5, other than arms 98 and receiver 100, are known in the art and are not shown.

The rear part 80 of the mold is provided with a recess 102 in which one half of the receiver 100 is received. This end is finally removed from the blade to form the blade trailing edge 76.

As shown in Figures 6 and 7, a preferred embodiment of the invention for an assembled blade includes only the rear baffle structure as a subassembly, in which the following surfaces are engaged: They fit together but are not stuck together. That is, the spar engaging surface 51 of the front end block 18 engages the spar 12, and the front end block engaging portion 46 of the cap member 16 engages the front end block 18 or the deicing blanket 40, as the case may be.
The girder engaging portion 48 of the cap material 16 engages with the girder 1.
2, the rear rectifying skin plate engaging portion 50 of the cap material 16 engages with the rear rectifying skin plates 28 and 30, and the spar rear end material engaging portion 52 of the spar 12 engages with the spar rear end material 24.
is engaged in.

The final assembly is completed by lowering the upper portion 82 of the single assembly mold into a closed position and applying heat and pressure to the assembly blade, as seen in FIG. For this purpose, the upper part 8
2 is connected to a press machine not shown in the figure.

As one of the more characteristic embodiments of the present invention, the front end block 18, the deicing blanket 40,
If the spars 12 are prefabricated or procured as structural members, the engagement surfaces, as previously described, may be attached using any suitable conventional adhesive. That is, each mating surface is coated with adhesive prior to its mating, and the so mated surfaces are bonded by applying heat and pressure to the assembly in a single assembly mold. It is made to be fixed.

In one preferred embodiment of the invention, the leading end block 18, deicing blanket 40, and spars 12 are laid up as described above and then positioned in a single assembly mold. This subassembly, along with the aft baffle structure subassembly, is then subjected to the heat and pressure of a curing process, such that its forward end block 18, deicing blanket 40, and spars 12 are in contact with each other as described above. At the same time as the surface is fixed, it is made into a structural member.

When laying up, for example, a de-icing blanket 40 within the cap 16, one or more layers of tape 104 are applied to the interior surface of the cap (as shown in FIG. 8) by a suitable conventional adhesive. . Additionally, a grid layer 106 incorporating wires 108 is attached to this tape layer, also by adhesive. Finally, another tape layer or layers 110 are applied to the exposed surface of the grid layer 106 with adhesive. This grid layer 106 may be like a printed circuit board if desired. The adhesive primarily positions the blanket within the cap material so that the front end block 18 can be laid up directly into the cap material and the laid-up spar can then be positioned and inserted into the cap material. That's true. When positioned in this manner, a portion of the deicing blanket 40 fills the slot 55, completing a continuous wall from the outer surface of the cap material to the inner surface of the girder in cross-sectional view. Such a continuous wall improves the load sharing properties of the rotor blade, in part because the support structure of the deicing blanket itself becomes a load sharing member.

Further, as seen in FIG. between the inner surface of the girder inside the area, i.e. the outermost layer of cap material, the next layer of skin, the inner layer of U-shaped girder back end material, and the innermost D-shaped layer. A spanwise continuous, extremely strong wall is completed in which four of the girder layers are bonded together. This design is called a "tuck-in" design, and this tuck-in wall can withstand shear forces along the longitudinal surface of the rotor blade airfoil shape, providing extremely effective load transfer while simultaneously It shall be capable of withstanding shear forces along this spanwise wall of the rotor blade assembly for highly effective load transfer, and shall be sufficient to withstand the spanwise bending and torsional strength of the rotor blade assembly. can do. Therefore, it is very effective to assemble and secure the rear baffle structure with the spars and cap material to provide a fail-safe design. This is also highly effective from the standpoint of transmitting load to the rear rectifying structure. This has the advantage that the overall load distribution is large and the load-bearing capacity of the rotor blade itself is large.

As already mentioned, one feature of the present invention is that the rear end member of the U-shaped girder extends in the span direction to form the root of the blade together with the girder and the cap material. The spars, caps, and spar tails transition at the root of the blade so that the spars and the U-shaped spar tails transition to create a preferably square cross-section. Because the spar is preferably formed as a laid-up structure that is cured in a single assembly mold, it is important that the spar tail end extends beyond the rear straightening structure and to the same extent as the spar. , to ensure that the spar is formed correctly during the curing process.

The following is an example of the operating parameters used in manufacturing a composite blade according to the present invention using the lay-up method.

1. Use pre-impregnated monofilament fibers as the lay-up material.

2 Rear rectification structure is 50-100psi (3.5-7Kg/cm),
Cure at 250℃ (120℃) for 2 hours.

3 digit rear end material is 70~100psi (5~7Kg/cm), 250
〓Cure at (120℃) for 2 hours.

4. The curing process in a single assembly mold is performed at 250 mm with a girder bag pressure of 70-100 psi (5-7 Kg/cm).
(120℃) for 2 hours.

When using a titanium cap material and deicing blanket, 70 to 100 psi (5 to 7 kg/cm), 250
〓A bonding method that requires 2 hours at (120℃) is required.

As is clear from the above description, each of the above-mentioned objects of the invention has been achieved, and an ideal composite structure such as a composite rotor blade has been obtained.

Furthermore, according to the invention, the spar only needs to be heated once to the curing temperature. During the curing process, the bonding surfaces are simultaneously bonded, improving the bonding properties of all bonding surfaces, resulting in a product with superior reliability and safety compared to conventional manufacturing methods. . Moreover, the attachment of the spars to the rear baffle skin is a fail-safe construction and eliminates the need for close tolerances and difficult secondary bonding in critical boundary areas.

Note that although numbers are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

FIG. 1 is a top view of a rotor blade assembly for a helicopter manufactured by the method of manufacturing an aerodynamic rotor blade assembly according to the present invention;
Figure 2 is a sectional view taken along line 2-2 in Figure 1;
~7 Each figure shows each stage of manufacturing the rotor blade assembly, Figure 8 is a detailed view of a part of Figure 2, and Figure 9 is a sectional view of the rotor blade assembly according to the conventional manufacturing method. . 10...composite blade, 12...digit, 14...
Rear rectifying structure, 16... Cap material, 18... Front end block, 20... Wing tip cover, 22... Root of blade, 24... Spar rear end material, 26... Core, 28... Top outer plate , 30...lower outer plate, 32
... Trailing edge wedge material, 40 ... Deicing blanket.

Claims (1)

[Scope of Claims] 1. A method of manufacturing an aerodynamic rotor blade assembly, which assembly comprises: (a) an outer surface forming a leading edge 44 of the blade, a leading end block engaging portion 46, a spar engaging portion 48 and A cap member 16 having an inner surface having a rear rectifying skin plate engaging portion 50; (B) a front end block 18 having a spar engaging surface; and (C) a U-shaped spar rear end member 24; (d) a spar 12 having an outer surface having a blade root portion 22 and a spar rear end material engaging portion 52; (e) forming a trailing edge of the blade and having an upper surface, a lower surface, a front surface and a rear surface; A rear baffle structure 14 comprising a lightweight core 26 whose upper and lower surfaces contour to desired portions of an airfoil shape, and outer plates 28 and 30 fixed to the upper and lower surfaces of the core 26, respectively; f) The cap material 16 and both outer panels 28, 30
and a wing tip cover 20 having a surface that engages with the wing tip cover 20, and the manufacturing method includes the following steps: (a) a step of making the rear flow straightening structure 14 in an adhesive assembly jig; (i) forming outer plates 28 and 30 on each of the upper and lower surfaces of the core 26;
(ii) the front surface of the core 26 and each of the outer panels 2;
8, 30 with an adhesive; (iii) applying heat and pressure to the adhesive assembly jig to fix the mounting surfaces to each other; (b) ) In the following states (i) to (v), the girder 12, the cap material 16, the front end block 18, the rear rectifying structure 1
4 and the wing tip cover 20 in a single assembly mold, (i) The front end block engaging portion 46, the spar engaging portion 48, and the rear straightening skin engaging portion 52 on the inner surface of the cap material 16 are , the front end block 18, the spar 12 and the rear baffle skins 28, 30, respectively.
(ii) The spar engaging surface 51 of the front end block engages with the spar 12. (iii) The spar rear end material engaging portion of the outer surface of the spar 12 engages with the spar 12. (iv) the surface of the wing tip cover 20 engages with the cap material 16 and both outer plates 28 and 30; (v) (i) to (iv) above; (c) securing said mounting surfaces together by applying heat and pressure within said single assembly mold to form an aerodynamic rotor;・Process of making the blade assembly. 2. In the step of creating the rear rectifying structure in the adhesive assembly jig, outer plates 2 are attached to each of the upper and lower surfaces of the core 26.
A method of manufacturing an aerodynamic rotor blade assembly according to claim 1, wherein the step of attaching the core 26 with an adhesive is performed after the next pre-step, (i) attaching the core 26 to the adhesive assembly method. (ii) machining the lower surface of the core 26 so that it is inclined with respect to the upper surface of the core 26 so that the cells of the core 26 face vertically when placed in a tool; (ii) the machined core 26; (iii) machining the upper surface of the core 26 to have a predetermined contour; (v) removing the simulated outer panel. 3. The step of placing in the single assembly mold,
Claim 1 or 2, wherein only the spar 12 is laid up, and the other cap material 16, front end block 18, rear baffle structure 14, and wing tip cover 20 are arranged so as to engage with the spar 12. A method of manufacturing an aerodynamic rotor blade assembly as described in Section 1. 4 In engaging the girder rear end member 24 with the outer surface of the girder 12 in claim 1(b)(iii), a recess 53 is provided on the outer surface of the girder 12, and a recess 53 is provided in the recess 53. While overlapping and fitting the front end sides of the outer panels 28 and 30 and the front end side of the girder rear end material 24,
Claim 1, in which the rear end side of the cap material 16 is overlapped on the outside thereof and engaged in a multiple structure.
The aerodynamic rotor according to any one of paragraphs to 3.
Blade assembly manufacturing method. 5. A method for manufacturing an aerodynamic rotor blade assembly, which assembly comprises: (a) an outer surface forming the leading edge 44 of the blade, a leading end block engaging portion 46, a spar engaging portion 48, and a rear baffle skin engaging portion; (b) a front end block 18 having a girder engaging surface; (c) a U-shaped girder rear end member 24; (d) a blade root portion 22 and (e) A spar 12 having an outer surface having a spar trailing end material engaging portion 52; a rear rectifying structure 14 comprising a lightweight core 26 having the outline of a portion thereof, and outer plates 28 and 30 fixed to the upper and lower surfaces of this core 26, respectively, and (f) the cap material 16 and both Outer panels 28, 30
and a wing tip cover 20 having a surface that engages with the wing tip cover 20, and the manufacturing method includes the following steps: (a) a step of making the rear flow straightening structure 14 in an adhesive assembly jig; (i) laying up one of the outer panels 28 and 30 in the jig and engaging the laid-up outer panel with the lower surface of the core 26; (ii) (iii) laying up the other of the outer panels 28 and 30 in the jig and engaging the laid-up outer panel with the upper surface of the core 26; (iv) applying a curing process to each of the laid-up outer panels 28, 30; By applying heat and pressure, we finish these into structural members, and
The process of simultaneously fixing all engaged surfaces. (b) In the following conditions (i) to (v), the girder 12, cap material 16, front end block 18, rear rectifying structure 1
4 and the wing tip cover 20 in a single assembly mold, (i) The front end block engaging portion 46, the spar engaging portion 48, and the rear straightening skin engaging portion 52 on the inner surface of the cap material 16 are , the front end block 18, the spar 12 and the rear baffle skins 28, 30, respectively.
(ii) the spar engaging surface of the front end block is engaged with the spar 12;
(iii) the spar trailing end material engaging portion 52 on the outer surface of the spar 12 engages with the spar trailing end material 24; (v) the surface of the wing tip cover 20 engages with the spar trailing end material 24; (vi) Each of the engaging surfaces (i) to (v) above, which engages the cap material 16 and both outer panels 28 and 30, is attached with an adhesive. (c) bonding the mounting surfaces together by applying heat and pressure within the single assembly mold to create an aerodynamic rotor blade assembly; 6. In the step of creating the rear rectifying structure in the adhesive assembly jig, outer plates 2 are attached to each of the upper and lower surfaces of the core 26.
6. A method of manufacturing an aerodynamic rotor blade assembly according to claim 5, wherein the step of attaching the core 26 with an adhesive is performed after the next pre-step. (ii) machining the lower surface of the core 26 so that it is inclined with respect to the upper surface of the core 26 so that the cells of the core 26 face vertically when placed in a tool; (ii) the machined core 26; (iii) machining the upper surface of the core 26 to have a predetermined contour; (v) removing the simulated outer panel. 7. The step of placing in the single assembly mold,
Claim 5 or 6, wherein only the spar 12 is laid up, and the other cap material 16, front end block 18, rear baffle structure 14 and wing tip cover 20 are arranged so as to engage with the spar 12. A method of manufacturing an aerodynamic rotor blade assembly as described in Section 1. 8. In order to engage the spar rear end material 24 with the outer surface of the spar 12, a recess 53 is provided on the outer surface of the spar 12, and the front end sides of the outer panels 28, 30 and the spar rear end material 24 are inserted into the recess 53. The aerodynamic rotor according to any one of claims 5 to 7, in which the front end sides of the cap material 16 are overlapped and fitted, and the rear end side of the cap material 16 is overlapped on the outside thereof and engaged in a multiple configuration.・Blade assembly manufacturing method.