Actuating Means For A Vane

Abstract

A mechanism, two of which position a vane in proper working and aerodynamic relationship with a flap throughout the latter's travel in a Fowler flap assembly for an aircraft. The forward end of a folding linkage is operatively connected, via a vane support fitting, to a vane, and is operatively connected at its rear end to a flap. Each vane support fitting is secured to one or more carriages having banks of rollers mounted on tracks fixed to wing structure. A cam is mounted on the forward end of the linkage to co-act with a follower stationarily disposed upon wing structure. In flap extension, the latching of cam upon follower prevents the folded linkage, its vane support fitting and vane from further opening and extending. Continued rotation of the unfolding linkage and cam provides disengagement from the follower. The linkage unfolds to a biased stiff or unyielding position as the flap pulls the linkage. In flap retraction, engagement of cam with follower breaks the biased unyielding position of the linkage. The linkage folds as the flap retracts. The vane does not further retract until the linkage is folded to a degree where the cam can pass by its follower. The folding linkage includes a spring-piston-cable arrangement which assures biasing thereof in its unyielding and extended position, until the cam engages the follower in the retracting mode for the flap.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The field of art to which the invention is most likely to pertain is located in a class of devices generally relating to lift increasing devices for airplane wings.

2. The Prior Art

Examples of prior art devices in the arts to which this invention most likely pertains are U.S. Letters Pat. Nos. 2,169,416; 2,404,956; 2,624,532; 3,528,632; and German Pat. No. 1,296,527 (May 29, 1969).

3. Problems in the Prior Art

It is believed that this invention is a completely novel one, as I am not aware of any major problems existing with similar mechanisms that have been utilized in aircraft in the past. Long sliding mechanisms are known to be commonly used for extending and retracting flaps and vanes; however, a need for this invention has developed in view of the heavier wide-bodied and jumbo jet aircraft of today. This need demands a simple, lightweight and nevertheless efficient mechanism for extending and retracting flaps and vanes of such aircraft. This invention solves such need.

SUMMARY OF THE INVENTION

This invention relates to lift increasing devices mounted on aircraft wings, and in which a trailing portion is separated from the wing's main portion, and is particularly related to a mechanism which actuates such a trailing portion.

Briefly summarized, the present invention is utilized in connection with a Fowler flap action desired to be taken for extending and retracting a vane and flap of a wing of an aircraft. A pair of vane actuator mechanisms are employed in an expanding double-slotted flap configuration for the wing. Each vane actuator mechanism includes a folding linkage at each (rib) side of the vane. The forward end of the linkage connects to a vane support fitting and its rear end connects to a flap actuating yoke or fitting, however, being driven by a flap actuating trunnion. Each linkage is held in an unyielding, unfolded position when the vane is fully separated from the flap, by means of a biasing means coupled with an over-center pivotal hinge connecting the members of the linkage. As the flap retracts, a cam at the forward end of each linkage engages and is held by or latches upon a roller mounted on relatively fixed structure thereby exerting a force on the linkage to cause it to break from its biased unyielding position. As the flap continues to retract to its nested position, the linkage continues to fold to its closed position. Continued folding of the linkage frees the cam from its follower and the vane approaches its nested position with the flap. Upon extending the flap, the cam engages its follower, such contact serving as a forward latch preventing the vane from further extending until the folded linkage is unfolded to a degree at which the cam passes by the follower. The extending flap in its movement can then continue to draw the linkage and the vane until the flap is in its fully extended position. Means are provided the linkage to bias it in its unyielding position.

An object of this invention, therefor, is to extend and retract such trailing portion by novel means.

Another object of this invention is to properly separate and space a wing, vane and flap relative to each other during such extension and retraction, for realization of advantages gained by the aerodynamic slotting achieved.

A further object of this invention is to maintain such proper separation and spacing of the wing, vane and flap during the retracting and extending modes of operation for the flap system.

A further object of this invention is to provide an actuator mechanism which is unaffected by any wing deflection or flexing.

A still further object of this invention is to provide an aerodynamically clean, lightweight, simple and efficient apparatus.

These and other objects of the invention will become more fully apparent upon a complete reading of the following description, appended claims thereto, and the drawing comprising five sheets.

BRIEF DESCRIPTION OF THE DRAWING

FIGS. 1-4 schematically represent in four views various positions of an airfoil on which the Fowler flap principle is employed and in which such airfoil this invention is employed.

FIG. 5 is an elevational view of a mechanism, in a closed or folded position, embodying the invention.

FIG. 6 is a view taken on line 6--6 of FIG. 5.

FIG. 7 is a perspective view of the mechanism in a fully extended position.

FIGS. 8, 9 and 10 schematically represent the vane actuating mechanism in fully closed, partially open, and fully open or unfolded positions, respectively.

FIG. 11 is a view partly in section and partly in full, of a biasing device employed in the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Background. The schematic views of FIGS. 1-4 represent the desired positions for a flap f and a vane v employed in an aircraft wing W utilizing the well-known Fowler flap principle. In a retracted position shown in the first view, the flap and vane are nested together in the trailing edge or portion of the wing, and thereby occupy minimum space. In FIG. 2, the Fowler principle becomes apparent, as the flap is extended for take-off of the aircraft. The flap panel has been extended for a maximum increase in wing area of a given aircraft, and is deflected to a desired angle .alpha.. In this position, the vane remains nested and is separated from the flap, exposing a single slot s.

FIG. 3 represents further deployment of the flap towards its fully extended position (for landing) which is shown in FIG. 4. The third view shows that the vane plugs the cavity formed in the trailing edge as the flap further extends, and also serves as an air control panel for a smooth flow of air through the original slot s. As the flap is continued to be fully deployed, or extended for landing, the vane extends from its position near the trailing edge. A second slot S is established and is shown in FIG. 4. The angle of the flap in the meantime is further increased to another desired angle .beta..

This invention is directed to achieving the maintenance of an efficient aerodynamic relationship for the vane with the flap throughout the latter's travel in the retracting and extending modes of their operation.

Description. Referring now to the drawing in which reference characters correspond to like numerals hereinafter, reference character 20 (FIG. 7) refers to and identifies a preferred embodiment of the invention. It should be understood that a pair of mechanisms 20 is used at each side or rib end of each flap and its associated vane on an aircraft; however, for clarity of description of the invention, the following description and the accompanying drawings are directed to just one mechanism 20. A like mechanism 20 complements same in actual outboard or inboard installation and operation of a flap and vane mounted in a wing of the aircraft, and its elements are merely situated in a reverse position to their corresponding elements shown in the accompanying drawing.

The actuator 20 comprises a linkage 21 having its forward end connected to a support member or fitting 22 on the rear end of which a vane lug 23 is adapted for pivotal connection thereto. The rearward end of the linkage 21 is operatively connected to an actuating yoke or flap hinge fitting 24 to which a flap (not shown) is secured. At the forward end of the linkage 21, a cam member 25 is mounted for cooperative action with a follower 26 mounted upon a bracket or extension member 27 secured to wing structure, or in this instance to a torque box 28. The vane support fitting or member 22 is connected to one or more carriage assemblies 29 having banks of rollers 30 which cooperate with fixed opposing tracks 31 (FIG. 6) included in the torque-box 28 fixed to wing structure. The actuating yoke or flap hinge fitting 24 for the mechanism 20 is adapted to be secured to the flap by suitable means such as bolts or the like extending through apertures 32 provided in the yoke 24 and as shown in FIG. 7. Although not illustrated, each flap is operatively mounted upon carriages or the like also having banks of rollers which ride in corresponding tracks in the same manner as the carriage assemblies 29 and rollers 30 which provide the guiding movement for the vane fitting or support member 22. The actuation of the flap itself may be accomplished by operation of a conventional ball-screw mechanism 33 to which a flap actuator fitting or trunnion 34 is operatively mounted. The actuating yoke or flap hinge fitting 24 is rotatably mounted about the trunnion 34. It is sufficient to note that actuation of the flap ball-screw mechanism 33 causes the trunnion 34 to extend or retract and thereby extend or retract the flap and operate the mechanism 20.

The linkage 21 includes a pair of rigid members or casings 35, 36 (FIGS. 7, 11) having their complementary ends pivotally connected together as at 37. A bifurcated element 38 is included in the forward end of the rigid member 35 for securing it to a lug 39 projecting from a rotatable spindle 40 (FIG. 6) laterally supported by and mounted in the vane support fitting 22. A bifurcated element 42 is mounted at the rear end of the rigid member 36, to be pivotally attached, such as by a bolt 43 to an arm 44. The arm 44 is spline bolted by a bolt 45 to the flap actuator trunnion 34. It should be understood that the arm 44 is required in the operation of the linkage as illustrated in this embodiment. However, it is not a necessary limitation on the spirit or to the merits of the invention.

As shown in FIGS. 7 and 11, the pivotal connection 37 for the rigid members 35, 36 is offset from their longitudinal axes. This offset coupled with a biasing arrangement 50 of elements (FIG. 11) for the casings forming the rigid members 35, 36 biases the linkage 21 in a direction tending to maintain it in an open or unfolded, and unyielding position.

Such arrangement 50 comprises an elongated coil spring 51 mounted in the length of a hollow casing for the rigid member 36, a piston 52 seated on one end of the spring 51, and a cable 53 one end of which being attached to the piston 52 and its other end to a point 54 on the rigid member 35. An opening 55 is provided in the casing base 56 in order that the cable 53 extends for attachment to the rigid member 35. The compressive force of the spring 51 tends to maintain the piston 52 at the top or right end (FIG. 11) of the rigid member 36, thereby exerting a force through the cable 53 to maintain the rigid member 35 in a hard position relative to the base 56 of the other member 36.

As shown in FIGS. 5 and 7, the cam 25 is mounted at the one end of the rigid member 35, and by virtue of its securement to the lug 39 to which the bifurcation 38 is fixed, it rotates or turns in unison with such rigid member 35 in the folding and unfolding of the linkage 21. The cam 25 comprises a circular riding face 60 and a tang 61 formed thereto. The tang 61 includes a cut-away face 63 contiguous to the circular face 60. In the folded position for the linkage means 21, it will be observed (FIG. 5) that as the circular face 60 cooperates with the stationarily disposed follower 26, by direct contact, the cam 25 is prevented from further moving to its right. However, as the linkage unfolds, the cam rotates with the rotation of the rigid member 35. The follower 26 continues to latch upon the face 60 until the rigid member 35 has rotated through an arc at the end of which the face 60 no longer contacts the follower. The cam's cut-away face 63 in turn does not fall along a path through the follower 26 and is in a position to pass by the follower 26, thereby freeing the unfolding linkage 21 to translate rearwardly.

Each vane support fitting or support member 22 is connected to one or more carriages 29. Preferably, a carriage assembly 29 includes a mounting element 65 (FIG. 7) mounted to a universal ball joint (not shown) situated on an extension shaft 66 integrally projecting from a bolt 67 which is secured to and through the lateral thickness of the vane support fitting 22. In the preferred embodiment, the carriage assembly 29 for each vane support fitting 22 comprises two in number and are spacedly mounted along an exterior side of and along the forward half of each support fitting. It will thus be seen from FIGS. 6 and 7 that each vane support fitting 22 is guided in its movement by the translation of its associated carriage assembly 29 within the torque box 28 and upon the vertically oriented tracks 31 by means of rollers 30.

A stop block 70 (FIGS. 8, 9, 10) is securely provided in the forward extremity of each torque box 28 to prevent the banks of rollers 30 on the carriage assemblies 29 from running off their tracks while also maintaining each actuator mechanism 20 in operable relationship relative to its associated vane and flap.

OPERATION

Extension. Referring now to FIGS. 8, 9, 10 and FIGS. 1-4, the extension of each flap f and vane v from their nested position (FIG. 1) is initiated by the flap's own ball-screw mechanism 33 in a manner well known in the art. Each actuating yoke 24 thus pulls a folded linkage 21 along with the extending flap. As the flap continues to extend, the circular face 60 of each cam 25 continues to engage or latch upon its stationarily disposed follower 26 to prevent translation of its associated vane support fitting 22, etc., and the vane v. Each linkage 21 continues to unfold with the extending flap, as shown in FIG. 9 and FIG. 2. Each cam 25 is continuing to rotate until the cut-away face 63 on its tang 61 is able to pass by or unlatch from its follower 26. The flap assumes the position shown in FIG. 3 and FIG. 10 wherein the members 35, 36 of each linkage are hard against each other. As the flap f continues to be extended, each vane support fitting 22, etc., translates rearwardly, by the pulling of the flap. Both the flap f and the vane v now assume a fully extended position shown in FIG. 4.

Retraction. The retraction of the flap f is initiated by its ball-screw mechanism. Both the flap and the vane translate forwardly, as each biased linkage 21 continues to remain in its unfolded or unyielding position. As soon as each cam's tang 61 engages its follower 26, a force is exerted upon its corresponding linkage 21 to break it about its over-centered pivotal hinge 37. Each linkage 21 pivots about the pin 37, thus initiating its folding. The vane v no longer continues to retract with the flap; however, the flap f continues to retract while further folding each linkage 21. Each cam 25 continues to rotate around its follower 26 and as soon as each cam in its rotation is free of its follower 26, the carriage assemblies 29, each vane support fitting 22, etc., and thus the corresponding vane v, again translates further inwardly until each fitting 22 engages its stop block 70 provided at the front end of its torque box 28. The flap f continues to retract, and each linkage further folds until it reaches its fully closed position. Both the flap and vane return to their nested position as shown in FIG. 1.

It should be understood that various changes and modifications in design and position of essential elements from the illustrated embodiment may be made, without departing from the spirit and scope of the invention. For example, in regard to an inboard flap-and-vane embodiment, the cam may be mounted on the center line of the rotatable spindle but between the vane fitting and the torque box. In such instance then, the roller is mounted on a flat bracket secured to and spaced from the side of the torque box.

In summary, the invention relates to a foldable linkage mechanism for delaying the action of a flap actuator to provide a desired movement of a vane segment of a Fowler flap assembly. The actuator comprises an elbowed linkage having two arms which constantly tend to assume an unbent configuration against a spring-piston-cable arrangement but which, upon application of a force to the forward end of one of the arms, may assume a folded position at its intermediate pivot point. Thus, the cable element of the arrangement bends around the pivot joint and stresses the spring element within the actuator. The actuator is utilized in combination with a cam and follower arrangement, the cam being mounted at such forward end of the linkage and the follower being attached to fixed wing structure. Upon extension of the flap system, the vane is initially restrained against motion, or at least against an undesired motion, by the engagement of the cam with its follower, until the principal flap segment is extended to a desired point. The cam element is then at a location with respect to its follower such that the linkage is enabled to unfold or function to position the vane in predetermined location with respect to the wing and its flap. Upon retraction of the flap assembly, the cam engages the follower to cause retraction of the vane actuator mechanism to its folded condition during the final retraction phase.

Pursuant to the requirements of the patent statutes, the principle of this invention has been explained and exemplified in a manner so that it can be readily practiced by those skilled in the art to which it pertains, or with which it is most nearly connected, such exemplification including what is presently considered to represent the best embodiment of the invention. However, it should be clearly understood that the above description and illustrations are not intended to unduly limit the scope of the appended claims, but that therefrom the invention may be practiced otherwise than as specifically described and exemplified herein, by those skilled in the art, and having the benefit of this disclosure.

Claims

Therefore, what I claim as patentably novel is:

1. In an aircraft wing lift increasing device including a vane and flap positioned and functioning in accordance with a Fowler flap action or principle and which includes means for mounting the vane and flap independently of each other but in sliding relation to their wing structure for the purposes of extending and retracting them in an efficient aerodynamic relationship,

an improvement for actuating the vane in proper and efficient relationship to the flap in such extension and retraction modes, and comprising in combination,

foldable linkage means comprising a pair of rigid members hingedly attached together at their adjacent ends, the respective free ends of said members constituting a forward end and a rear end for said linkage means, respectively,

means for biasing said members towards an unyielding, unfolded position for said linkage means,

a cam member in fixed and non-rotatable relation to and mounted on said forward end for rotation with its rigid member as said members unfold and fold, said forward end and cam member being adapted for rotation about the mounting means for the vane, and

means mounted on the wing structure and upon which said cam member engages as said linkage means movingly folds and unfolds during the extending and retracting modes for the vane and flap,

said cam member being disposed forwardly of said mounted means and with folded position for its linkage means, said cam member engaging said mounted means to prevent extension of the vane as the flap extends until the flap extends to a point at which said linkage means becomes unfolded to cause said cam member to become disengaged from said mounted means to provide for extension of the vane as the flap continues to extend,

said cam member with its unyielding, unfolded linkage means being disposed rearwardly of said mounted means, the vane remaining extended until said cam member engages said mounted means as the flap is retracting, such engagement overcoming said biasing means to break the unfolded linkage means, said linkage means continuing to fold to a point where said cam member disengages from said mounted means to thereby provide for retraction of the vane as the flap continues to retract.