JPH04503496A - rotor blade - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] name of invention rotor blade Technical field of invention The present invention relates to the structure of rotor blades used in helicopters and VSTOLs, especially those that can be folded. The present invention relates to a blade structure suitable for a folding rotor blade system.

Background of the invention Rotor blades for helicopters are well known. The rotor blades are also vertical short distance rattan take-off and landing. Also used for land (VSTOL) aircraft. In particular, the rotor blades are rotate to produce direct lift or horizontal thrust) t- rotate to produce Used in VSTOL aircraft where the wing blades pivot relative to the aircraft. The rotor blades are It is long and extends beyond the fuselage of the aircraft. i.e. folded during transport or storage The blades now take up less space without having to remove the blade or blades from the aircraft. It has the advantage of being able to provide feathers that can be used to protect people. In recent years, fiber composite blades have been widely used, and metal blades have been widely used. They have many advantages over rotor blades. However, composite feathers include folding feathers. There are unique manufacturing and design problems in creating vanes useful in root systems.

The reason why composite materials are used for rotor blades is that these materials have unique properties and are made of composite materials. It is possible to ensure that laminates made from composite materials as well as structures meet specific performance requirements. It is advantageous because it can be done. Composite products consist of one or more types of base materials in a continuous phase. Based on the controlled distribution of reinforcing material in the material, composite sheets can be It is formed by covering the reinforcing material with the base metal system. These materials are as follows The reinforcement is then rolled or otherwise processed to evenly spread the entire sheet to a uniform thickness. to occur. In this way, to fix the geometry of the sheet Partially cured with sufficient shape loosening (drape) and adhesion (stickiness) This makes it possible to create complex shapes from the composite sheet formed in this way. It can remove insects from impregnated systems. Before curing, these composite sheets are called bleepure rug sheets. Called. When creating the entire laminate, the sheets of composite material are placed in the desired orientation.

One example of creating a complex part is to create multiple sheets of pre-pre-rug material at the bottom in the desired orientation. Combine. This method is called layup (1ayup).

After layup, the composite sheets are glued together to form the finished laminate. The formed structure is cured.

The present invention allows the blades to be folded so that they can be stored without removing them from the aircraft. A rotor blade structure suitable for making composite rotor blades designed especially suitable for All that is offered.

Summary of the invention Shape the wing shape and form the chord line and rotor beam to generate aerodynamic lift. A rotor blade structure is obtained with an outer end that has an outer edge. At the inner end of the rotor blade, there is a An end tongue having an attached section and an extended ledge is attached. This end tongue is , a mounting hole with an axis parallel to the chord line of the airfoil, and a mounting hole extending inside this hole in the C-in direction. The lever (jointed) surface can be provided with an extension ledge on the molded bottom to resist bending. be. In a preferred embodiment, the inner end tongue is substantially attached to the beam of the rotor blade. having longitudinally spaced tongue-like extensions extending in each plane parallel to . Each end tongue extension is aligned with an axis substantially parallel to the chord line of the rotor blade. A mounting hole is formed. Each end tongue extends inside each hole and extends to the lever surface. form an extension ledge with a The holes in the front and rear end tongue extensions are aligned coaxially. It is better to match.

The rotor blades are of composite construction, with multiple filament-reinforced composite belts extending outside the airfoil. Extending from the side portions form end tongues. the first plurality of filament-reinforced strips are extending inwardly from the outer end of the rotor blade and extending partially into the end tongue; It is wrapped around a mounting hole having an axis substantially parallel to the chord of the section.

A second plurality of filament string composite belts extend inwardly from the outer portion of the vane. A tongue-shaped body extension is formed inside the attachment hole. In the preferred embodiment, these belts is the filling released from the composite laminate along with the shearing edges of the composite laminate spaced apart from each other. The materials are laminated to form a mounting hole and an extension VT-. belt, shear web and filler webs are laminated together to form a composite end tongue with the rotor. .

This structure allows the bending load of the vane to be guided inside the mounting (retaining) hole, making the hole Eliminates the need to extend the rotor hub beyond the blades and allows for a more compact arrangement when the blades are folded. It is advantageous in that it can be placed anywhere.

Brief description of the drawing Preferred embodiments of the invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view of one embodiment of the rotor blade of the present invention.

FIG. 2 is a partial perspective view of the rotor blade of the present invention attached to a hub grip.

FIG. 3 is a perspective view of a portion of FIG. 1 showing the forward end tongue extension.

FIG. 4 is a partial perspective view showing a stack of end tongues.

FIG. 5 is a perspective view showing the structure of the shearing edge and filler.

FIG. 6 is a plan view showing the orientation of reinforcing elements within the composite sheet.

FIGS. 7 and 8 are partial perspective views of different embodiments.

Figures 9a, 9b and 9a are perspective views of various reinforcing bands added to the extension ledge. be.

Example Traditional rotor blades are attached to the aircraft hoop with two bolts. These etc. The bolt passes through the blade tJj, which is approximately perpendicular to the chord line. Each bolt is located at the base of the blade. I'll leave it there. In these structures, all loads are subjected to reaction forces through the bolts. child The main loads in the area are the bending in the beam direction applied to the airfoil section of the rotor blade, the blade directional bending, torsional force and centrifugal force. On the other hand, in the present invention, the rotor blades are It is attached to the Gino de grip by Zalto, which also acts as a folding bin.

The axis of this bolt is substantially parallel to the local chord line of the rotor blade. This ball The blade supports chordwise bending, torsion, and centrifugal force, but the load causes the blade to bolt. Since it is rotated around the beam, bending in the beam direction cannot be supported. With this invention is an extension to the rotor blade tongue that allows the lever surface to resist bending in the beam direction. Set up a business trip.

FIG. 1 illustrates a perspective view of a rotor blade 10 of the present invention. outside of rotor blade The portion 12 has a mortar-like structure and has an airfoil 14 indicated by a broken line. The blade 10 has a longitudinal axis (beam) AA, with a The airfoil formed by It has a width CC as shown in FIG. The inner end of the blade 10 has a mounting portion 18 and an extension ledge. There is an end tongue 16 having a portion 20. End tongue 16 is a preferred embodiment. has two inner protruding parts, a front end extension tongue 22 and a rear end extension tongue 24. Two. Each end extension tongue 22, 24 is attached to a rotor blade such as to attach a blade to an aircraft. Hole 26.28t-formed in 2a with axis DD approximately parallel to the local chord of the blade.

Each mounting hole 26 and 28 allows a bolt to pass through the end tongue of the vane and connect the vane to the hub. so that it can be installed as desired. Zaruto that passes through these holes can also be used as a feather. A collapsible bin with a blade that rotates so that it can be folded to the tth position for storage. It works.

Each person 26.2E1 The penetrating zaruto supports bending in the string direction, torsional force, and centrifugal force. However, since the blade rotates around the bolt due to the load, the bolt is bent in the direction of the beam. cannot support it. Extended ledge to prevent complete rotation of blade in beam direction 20 is provided. Each of the front and rear end extension tongue-like bodies 22, 24 is an extension projection 930.32. have. Each extension ledge 50.52 has a hub grip on the inside of each mounting hole 26°28. Interaction of the retaining structure 1 (with extension lug j of each extension tongue 22.24) 50.32 It extends far enough to allow Each extension tongue interacts with the retention structure. Completely form the lever surface.

Each lever surface 36. ! 14 is an automatic lubricant such as tetrahydrofuran (Teflon) Plastic material or other self-lubricating plastic material can be applied.

This surface can be further reinforced with bands or boxes.

FIG. 2 shows that the front extension tongue 22 passes through the mounting hole 26 and the rear extension tongue 24 ( A wing attached to the hub grip 4o by a pin 42 passing through a hole 28 (not shown) Root 10t - shown. The bin 42 has an extension end 4 at the front and rear of the hub 4o Nikka 40. 4. Pass through the mounting hole formed in 46. Bending of the vane 10 around the bin 42 or The rotation is attached to the vane grip 40 by suitable means such as bolts 52, 54. Obstructed by stop 48.50. Extended tongue 22°2 indicated by dashed line 60.62 40 extension ledge 30.32 is securely held by stop 48.50 and remains in the bin 42. This is to prevent rotation of the rotating blade 1o or bending in the beam direction. rotor blades The roots 10 are stopped manually or by an automatic mechanism 48.51 and the blades are simply removed around the bin 42. It can be folded by pivoting. i.e. the blades of a multi-bladed rotor Roots can be folded together to minimize storage space.

FIG. 3 is a perspective view of the portion of the rotor blade included within the circular portion F of FIG. Before The end tongue extension lugs 30 of the extension tongues 22 are connected to a series of internal strips 70, 72. The laminated structure of the present invention exhibiting an edge between each outer strip and adjacent to these strips. Then, the shear web 62 is inserted. The outer band 84 is shown in dashed lines. rear end A similar structure is used for the tongue.

FIG. 4 is a partially exploded view of FIG. 3, showing the structure of the front end tongue 22. FIG. tongue-like end The body 22 may be composed of a series of laminates of which 3,180°82.84 is the only example. be. Inner band layer 80 includes inner band 70.72. These strips The inner ends 76, 78 of It is better to set the sea urchin direction. The outer portion 81.83 of the strip 70.72 is the widest It is best to orient the blade so that the opposite part is parallel to the beam of the rotor. In this case each band The body is constructed as illustrated in section 74 of FIG. 3 and extends beyond the beam of the rotor blade. Forms a continuous strip that extends.

These strips have reinforcing fibers 86 running approximately parallel to the beam axis of the rotor blade. It is better to set up and configure it.

An inner strip filler portion 88 is inserted between each inner strip. inner band filling The portion 88 includes alternating sections of the composite material for reinforcing fibers oriented in different directions. Consists of a laminate of reinforced composite material with sheets of. The orientation of the reinforcement element is the rotor blade It is preferred to be about ±15° to about ±90° from the vane beam.

The shear layer 82 orients the reinforcing elements of the sheet in different directions. Sheared sea urchin zoro 2-gara construction consisting of a laminate released from alternating composite sheets with a specified Ru. Also, this orientation must be between ±15° and approximately ±90’ from the rotor blade beam. No.

Adjacent to the sheared edge layer 82, an outer strip layer 84 is entirely provided. Outer band layer 8 4 is provided with an outer band 92 surrounding the outer loop filler 94. . The strands of reinforcing elements 9 in the outer band 92 are connected to the outer loop filler 94. A section of the outer band surrounding Dk is set substantially parallel to the beam of the rotor blade. lies within the plane. Adjacent to the outer strip is an inner light shield 98. Each charge For material 94.98, each reinforcing fiber is preferably approximately ±15° away from the beam of the rotor blade. It is constructed from a laminate of composite materials oriented in an alternating direction of approximately ±900 degrees. each The filler material 94,98 is shaped into the tongue end to match and mate with the outer band 92. It is molded. Each layer does not have to be arranged in any particular order. Also, outer band The order of the lamellae, inner zonal layer and sheared edema layer can vary. used The number of each layer may also be changed as necessary depending on the dimensions of the rotor blade, required strength, etc. Can be done. These layers are then adhered together to form front and rear end extension tongues.

Each layer is provided with a hole 100 forming a mounting hole such as the mounting hole 26 in the end tongue. . Alternatively, a solid laminated end tongue may be provided with a full bottom and a mounting hole may be drilled in these end tongues. stomach.

FIG. 5 shows the structure of the sheet web 62. The structure of each filling material 88, 94, 98 is The same is true. For illustration purposes, the sheared Unizoro 2 is made from reinforced composites laminated together. It has four sheets at the bottom. These four sheets 120, 122, 12 4,126゜Generally 4 or more sheets)? In this case, we will use four sheets for illustration purposes. cormorant. In the mortar type, 10 or more sheets are laminated. Each sheet is unidirectional It is better to have oriented reinforcing fibers. Each sheet is different from the adjacent sheets. Stack them on top of each other so that they are facing in the same direction. The number of laminated sheets depends on the desired area. Depends on the required thickness as well as the strength. Shear typically includes about 4 to 30 laminate layers The web proved to be effective. Generally at least 18 layers all achieve the desired strength However, they must be stacked on top of each other.

FIG. 6 shows two composite sheets 120, 122e with reinforcing elements 132, 136. . The orientation of the axes of the reinforcing elements 132 and 136 is set to the axis parallel to the beam of the rotor blade. The illustration is made with respect to the line 130. Line 132 rotates with the longitudinal axis of the reinforcing fiber. Reinforcement of one composite layer with an azimuth angle of 134, which is the angle between the wing blade beam The long axis of the fiber is shown. This angle (measures the minimum angle between the beam line) is 15 A angle between 90° and 90° is preferable. Preferably this angle is between about 25° and about 50°.

As shown, the second layer has a longitudinal axis, such as axis 136, running in the opposite direction from the other layers. have a line. The azimuth angle is that the azimuth of ±60° is almost the same as the azimuth of ±45° during shear. However, it is known that it has better abrasion resistance against bending force, so approximately ± It is best to set the angle to 25 to 35 degrees.

As shown in FIG. Extending from the end tongue to the top and bottom of the airfoil and the shaped portion of the airfoil composite structure. It is growing. A preferred embodiment uses a plurality of such strips. The outer band is Although acting to take centrifugal loads, the inner band transmits bending in the beam direction.

Each band is preferably constructed from a reinforced composite, and the band is generally measured to the desired strength. and can be varied according to the structure. In addition, the cross section of the strip has an alternating shape along the rotor blade. It varies according to different places. The width is about 1.6 to about 4.3 inches and the thickness is about 0. We have found that 3 to about Q.9 inch strips are suitable for use in the present invention.

Generally, each strip is more square at the inner end of the girder and more flat at the outer end. Ru. For example, near the inner end of the rotor blade, it is approximately 1.3 The outer ends of the rotor blades have a width of approximately 4.3 inches and a thickness of approximately 0.9 inches. It has been found useful to use flattened strips.

A composite is used to construct the entire blade. All end tongues are made of the same type of composite material. stomach. Alternatively, a combination of composite materials using different reinforcing elements can be used. Yui One requirement is that the composite sheet be a sheet that will bond to each other during the curing process. That is. Rotor blade extensions are generally attached after gluing and curing. Machine to desired shape. In one construction method, the outer band includes a rough end tongue. It can be assembled as a single band that wraps around the ends of the forming vane.

After curing, the end portions of the end tongues are cut away to form upper and lower outer bands. separation The layered sections are then collected and subjected to shear tests to ensure that the composite structure has the required strength and quality. conform to the standards of management.

The composite materials utilized in constructing the present invention are suitable for use in aircraft manufacturing. It can be anything you like.

Such materials require that the pre-impregnation be combined with other pre-impregnated materials along with the lath fiber reinforced epoxy material. Contains soaked reinforced composite materials. In addition to lath fibers, typical reinforcing filaments are carbon , graphite, aramid fiber (Kelper), borosilicate and one polymeric material. Ru. In a preferred embodiment, a plurality of bands of wound filament are utilized in the construction of a rotor blade. There is a body. Firamen)? Eight or more rolled strips are utilized. this It has been found that it is better to have a band like this running the entire length of the blade; The vanes are divided into two groups of four bands. The four strips at the front are the vanes. Forms part of the root extension. Of these four strips, the blade mounting hole is The two band-shaped bodies in place and the two remaining band-shaped bodies are the main bending load diameter of the root extension part. form a road. Using filler and shear webs between each strip to create a fully extended tongue. Complete configuration.

In a typical construction, the extension ledge has any desired length. From the mounting hole to the blade tip It is useful to have an extension that is approximately 7% of the length of the rotor blade by about 3 inches. I understand.

The rear extension is constructed similarly to the strip used for the front extension. Similar installation There are also four bands in the rear extension of the girder.

Installing a swing insulator at the blade root prevents deflection of the blade and hub in the axial and chord directions. can be generated in these directions without transmitting loads. oscillating insulator may be any self-lubricating plastic material such as Teflon cloth. i.e. the blade root can be covered by a Teflon cloth applied to the reinforcing band or to the stop. Ru. Teflon surfaces or other lubricated plastic surfaces also facilitate movement. It is used inside the pin mounting hole.

As shown, the end tongue has two extensions.

However, as shown in FIG. 7, the rotor blade 150 extends into the mounting hole 154 and inside the hole. A single end extension tongue 152 is formed with an extension ledge 156.

Also, the rotor blades have a full-bottom mounting hole, but only one has a lever surface. and two end extension tongues with extension lugs extending inside the mounting holes. Configure. The end tongue may also be configured to have two or more end extension tongues. I can do it. Such embodiments yield several possible combinations of end extension tongues. be able to. For example, in Figure 8, only the mounting holes 166° and 168 are coaxially aligned. If present, the rotor blade 160 is shown with two extended tongues 162, 164. sixth Extension portion 170 includes an extension ledge 17 that extends inside each mounting hole 166,168. form 2. Attachment holes may also be formed in the end extension tongue 170 if desired.

As shown in Figure 9, the extension ledge covers the joining (lever) surface with a reinforcing band. Protect the hub latch mechanism (stop) from contact with the hub latch mechanism (stop). Figure 9a shows the Polymer-reinforced band 182 that can be made from any suitable material show. FIG. 9b shows a metal reinforcing band 184f held by screws 18B.

Alternatively, the reinforcing band may be a box 188 (FIG. 9C) around the end of the extension tongue 180. It has the shape of This reinforcing band or box is a tight fit on the extension ledge and is screwed into place. Retained. Reinforcement bands provide localized support for overhanging edges or delay the onset of shear failure. It has the effect of causing Reinforcement bands can be made from metal, composite or elastomeric materials .

Metal should be used to provide the best protection against local deformation of the extension ledge.

Although the present invention has been described above in detail with respect to its preferred embodiments, the spirit of the present invention still remains. Of course, it is possible to perform various changes and transformations without deviating from the above.

Amended scope of claims Copy and translation of written amendment) Submission form (According to the provisions of Article 184-7, Paragraph 1 of the Patent Law) June 17, 1991

Claims (18)

[Claims] 1. a) an outer edge forming an airfoil surface defining a chord line; and b) the chord of this outer edge. an inner end of a rotor blade defining a mounting hole with an axis substantially parallel to the line and a lever surface; an end tongue forming an extended ledge extending inside said hole; A rotor blade that encompasses. 2. a) an outer end forming an airfoil surface defining the chord line; and b) attached to this outer end. a flat rotor blade defining an inner end of the rotor blade and substantially parallel to the outer end beam; It has front and rear extensions spaced apart from each other that extend in-plane and partition the mounting holes, respectively. said hole is coaxially aligned with an axis substantially parallel to the chord line of said outer end; At least one of the front and rear extension portions extends inside each hole and has a lever surface. An end tongue-shaped body configured to form tension. A rotor blade that encompasses. 3. Both the front and rear extension portions form an extension extending inside each hole. The rotor blade according to claim 2. 4. 3. The rotor blade of claim 2, wherein said lever surface is coated with a self-lubricating plastic material. 5. a) an outer part of composite material forming the airfoil surface and defining the chord line and beam; , b) Preparing mounting holes extending inwardly from the outer portion of said airfoil and having substantially parallel axes; forming a front extension tongue which further extends inside said hole; a first plurality of filament-reinforced composite strips configured to form elongated ledges; c) said outer end extending inwardly of said outer end and spaced from said front extension tongue; forming a rear extension tongue separating the mounting hole with an axis substantially parallel to the chord line of the wing; , this rear extension tongue further extends inside the hole formed in this to form an extension ledge. a second plurality of filament-reinforced composite strips configured to A rotor blade that encompasses. 6. Composite materials include carbon, graphite, boron, glass fiber and polymer filament. The round of claim 5 selected from a composite sheet having reinforcing elements selected from the group consisting of Rotating blades. 7. a) Partitioning outer end part of a profiled surface made of composite material and having chord lines and beams an outer end having a plurality of composite filament-wrapped bands extending inwardly; and, b) a mounting hole attached to the inner end of said outer end and a laminate extending inside this mounting hole; an extension ledge formed from the body; and an end tongue forming an extension ledge; , i) by an inner band filler element extending from said outer end and consisting of reinforced composite material; an inner strip layer with two outer strips spaced apart from each other; and ii) a composite material. a shear web layer adjacent to the inner band layer; iii) a compound formed by an outer band surrounding said mounting hole and reinforcing said surrounding; a filler element made of composite material and extending inwardly from the inner end of the outer strip; spaced apart by shear web fillers forming part of the long ledges. an outer zona layer held in an oriented configuration; iv) (i), (ii) or (i and one or more additional layers according to ii). 8. a) a second extension extending from the outer end and spaced apart from the first extension tongue; partitioning a mounting hole forming a tongue and aligning with the hole partitioned by the first extension tongue; a second number of composite filaments forming an extension ledge extending inside the mounting hole; b) a mounting hole attached to the inside of said outer end and a mounting hole within said mounting hole; an end tongue extending laterally and forming an extension ledge formed from the laminate; an extension ledge comprising: i) an inner strip extending from said outer end and comprising a reinforced composite material; an inner strip layer having two outer strips spaced apart from each other by a material element; i) a shear web layer made of a composite material and adjacent to said inner band layer; iii) a compound formed by an outer band surrounding said mounting hole and reinforcing said enclosure; a filler element made of composite material and a hole extending inwardly from the inner end of said outer strip; The portions of the extension ledges are held in a spaced apart arrangement by the cutting web fillers. an outer band layer formed to form a iv) (i), (ii) or (i) arranged in a predetermined order and stacked together with other layers; and one or more additional layers according to ii). wing feathers. 9. The reinforced composite material may be carbon, graphite, boron, aramid fiber and others. 9. The rotor blade of claim 8 having a reinforcing element selected from the group consisting of reinforcing fibers. root. 10. The filler elements are arranged such that each reinforcing element is within ±15° from the rotor blade beam line. 8. The rotor blade according to claim 7, wherein the rotor blade is oriented at ±90°. 11. Said filler element is arranged so that the reinforcing element is at an angle of ±15° or more from the rotor blade beam line. 9. The rotor blade of claim 8, wherein the rotor blade is oriented to be oriented at ±90°. 12. Said filler and shear web are bonded to said reinforcing element in said rotor blade beam line. The rotor blade according to claim 7, which is oriented at an angle of ±25° to ±35° from Feather. 13. Said filler and shear web are bonded to said reinforcing element in said rotor blade beam line. The rotor blade of claim 8, wherein the rotor blade is oriented at an angle of ±25° to ±55° from Feather. 14. a) an outer end defining an airfoil surface with a chord line and a beam line; b) two or more spaced apart parts attached to said outer end and extending inwardly; at least one of these extensions substantially parallel to the chord line. forming a mounting hole with a fixed axis, and forming an inner portion of the mounting hole in at least one of the extension portions; Forms an extension ledge that extends to the side and forms a lever surface that resists bending in the direction of the beam. with an end tongue-like body A rotor blade that encompasses. 15. The rotor blade of claim 1 including a reinforcing band attached to the extension ledge. 16. 3. The rotor blade of claim 2 including a reinforcing band attached to the extension ledge. 17. 6. The rotor blade of claim 5 including a reinforcing band attached to the extension ledge. 18. 8. The rotor blade of claim 7 including a reinforcing band attached to the extension ledge.