JPS61247598A - Air-operated type deicer - 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 Field of the Invention The present invention relates to a pneumatically operated device for deicing components of an aircraft. More particularly, the invention provides for a rubber bladder of resilient material, such as rubber, to be attached to an aircraft component and configured to be inflated by air to remove ice that has formed on the component. related to the equipment being used. Still more particularly, the present invention relates to an air-operated de-icing system for application to aircraft components such as wings and struts having sharp leading edges in the form of so-called knives or wedges.

[Conventional technology]

Since the early days of power-driven flight technology, aircraft have occasionally suffered from the accumulation of ice on the surfaces of aircraft components such as wings and struts under certain flight conditions.

If such build-up is not controlled, the aircraft will eventually be burdened by the added weight and will change the shape of the wing, thereby hastening the occurrence of a no-flight condition. Examination of means to combat ice accumulation under flight conditions continued and resulted in three universal methods of removing accumulated ice, commonly known as de-icing. .

In one form of de-icing, the leading edge, the leading edge of an aircraft component where air flowing over the aircraft impinges or has a stagnation point, is used to remove accumulated ice from the aircraft component. is heated to loosen the adhesive force between them.

Once loosened, this ice is typically blown away from the aircraft components by airflow passing over the aircraft. Two methods of heating the leading edge enjoy much popularity.

In one method, the heating element is located in the leading edge region of the aircraft component, either contained within a rubber bladder mounted over the leading edge or incorporated into the skin structure of the aircraft component. be done. This heating element is powered by electrical energy obtained from a power source, typically driven by one or more of the aircraft's engines, and provides sufficient heat to loosen the accumulated ice. can be switched on and off to provide In very small aircraft, typically powered by one or two engines, there is not a sufficient amount of electrical power available to use electrical de-icing systems.

In other heating methods, gas from one or more compression stages of a turbine engine at elevated temperatures is circulated through the leading edges of components such as wings and struts to provide thermal de-icing or de-icing. be done. The use of so-called compressor effluent or bypass flow from the aircraft engine turbine in aircraft powered by turbine engines results in reduced fuel savings and reduced turbine power output.

In limited situations, chemicals are applied to all or a portion of an aircraft to reduce the adhesion of ice to the aircraft or to lower the freezing temperature of water that collects on the surfaces of the aircraft.

Another commonly used method for deicing is typically referred to as mechanical deicing. In air-actuated de-icing methods, which are the primary commercial mechanical de-icing means, the leading edge of an aircraft wing or strut component is inflated with a plurality of expansions that can be expanded with a compressed fluid, typically compressed air. Possible to be coated with almost tubular structure. Upon inflation, this tube structure expands the leading edge shape of the wing or strut to break up ice that has accumulated thereon and scatter it into the airflow passing over the aircraft components. Typically, this tube structure was shaped to extend substantially parallel to the leading edge of the aircraft component.

For airfoil shapes such as the main wing or horizontal stabilizer, these structures can extend the total span of the airfoil. A plurality of tube structures are shaped to be typically parallel to the leading edge of the wing or strut by arranging them in chord fashion away from the leading edge of the wing or strut. It is located on a pillar. The plurality of tubes provides ice removal to the overall leading edge shape of the wing or strut.

Certain aircraft components can have a variety of leading edge shapes. One traditional shape is the plant (rounded tip)
Otherwise known as a pull nose, it has a substantially rounded leading edge shape with a radius that is a substantial proportion of the chord of the leading edge, typical of many older aircraft. Such plant shapes typically have generally smoothly rounded, large radius dots.
Contains the leading edge of the (vault) shape. In other frequently used component profiles, this leading edge exhibits less rounding resembling a so-called quadrant V, but this profile still has a substantial curvature of a certain proportion of the chord. Includes the substantial roundness of the leading edge of an aircraft component characterized by radius.

More recently, leading edges called wedges or knife edges have been used. In a wedge or naivete leading edge, the surfaces of a pair of essentially flat aircraft components have a moderately rounded surface area characterized by a radius of curvature of a relatively small proportion of the chord of the leading edge. It has an acute angle and is joined.

Such a wedge-shaped or knifest leading edge shape presents certain significant difficulties in applying conventional air-actuated de-icing techniques to de-ice this leading edge.

Ice accumulation efficiency is high on the small radius leading edge, which is characterized by a knife shape, and ice accumulation efficiency is lower towards the tail of this leading edge, so that ice is deposited in a relatively narrow band along the leading edge. With conventional de-icers that include a pair of pneumatic actuated tubes that span the leading edge, the accumulated ice does not receive the significant movement required by expansion of the straddling de-icing tubes. If the icer tubes are arranged evenly and symmetrically with sections of equal width on each surface to wrap around the leading edge kniffe,
As the deicer tube expands without fragmentation or breaking to facilitate deicing, the accumulated ice tends to be forced forward along the wing structure. This creates a cavity between the accumulated ice and the air-operated de-icer such that subsequent expansion cycles of the air-operated de-icer are ineffective in removing the ice accumulation.

An air-operated de-icer with a knife or wedge-like leading edge configuration that provides reliable ice-breaking action and eliminates forward movement of accumulated water along aircraft components during expansion.
In particular, it has found substantial application in the de-icing of main wings, horizontal stabilizers, struts and other appendages having leading edge shapes such as those described above.

[Problem that the invention seeks to solve]

The present invention provides an air-operated de-icer for the deicing of so-called knife edges or wedge-shaped portions of aircraft components such as wings, tailplanes, struts and other appendages. The deicer of the invention has a so-called knife shape or wedge shape formed by the intersection of two essentially flat surfaces and is characterized by a very small radius of curvature for the air flow flowing over it. It is uniquely shaped for use on an aircraft component that exhibits a leading edge shape.

SUMMARY OF THE INVENTION In the present invention, an air-operated deicer having one or more expandable or inflatable tube structures is applied to the above components and Each inflatable tube structure of the deicer has a respective length and width. Typically its length is substantially greater than its corresponding width and the deicer is positioned over the component such that its length is generally parallel to the leading edge of the component. One of these tubular structures lies on one essentially flat surface that wraps around the leading edge and intersects at the leading edge, approximately 55% or more of the width of this particular tubular part. and a portion of the remaining width of said tubular portion that wraps around the leading edge and rests on another essentially flat surface intersecting the leading edge. It is located. The width of the single tubular portion that wraps around the leading edge is therefore shaped to wrap asymmetrically around the leading edge.

The asymmetrically shaped tubular section is then alternately expanded and contracted to deice the leading edge of the margin knife or tapered edge. If additional tubular structures are attached to the surface of an essentially planar component that intersects at the leading edge, these tubular structures will also have their lengths approximately parallel to the leading edge. be made to be. These additional tubular structures on essentially flat surfaces that break at the leading edge are simultaneously inflated and deflated in conjunction with the asymmetrically mounted tubular structures. Instead, these additional tubular structures are inflated in a staggered manner, such that the inflation pattern begins with the expansion of the asymmetrically disposed leading edge tubular structures and then across one or both of the essentially flat surfaces. The expansion of the tubular structure continues in chord fashion.

[Operation and effect of the invention]

The asymmetrical placement of one tubular section wrapping around the leading edge provides protection against ice build-up on the leading edge during inflation and forwardly along a plane formed by the aircraft component being de-iced. A translational motion is imparted in a direction perpendicular to this plane formed by the parts, thus effectively breaking up the ice build-up and further removing this ice from stagnation points in the airflow flowing over the aircraft component at the leading edge. Allow buildup to normally leave. The movement of the ice away from the stagnation point increases the deicing effect by moving the ice away from the stable location where it has formed and by pushing the ice head further directly into the water-displacing airflow flowing over the aircraft components. promote.

These and other features and advantages of the invention will become more apparent when considering the drawings and the description of the preferred embodiments of the invention, which form a part of this specification.

EXAMPLE Referring to the drawings, FIG. 1 shows a leading edge portion 10 of a wing. This leading edge section 10 includes a pair of essentially flat airfoil surfaces 12, 14 that intersect at a so-called knife edge or wedge edge 16. What is meant by essentially flat is a radius of curvature, preferably close to infinity, that substantially exceeds the width of the surface, i.e. the distance between the leading edge and the not shown trailing edge for airflow over the surface. The surface is the surface. essentially flat surface 1
The alternating portion between 2 and 14 substantially defines an acute angle 18 . Typically this angle is less than 45°, and most typically this angle is no more than about 30°.

In many embodiments of the wing 10, this angle 18 is about 20
° It's super dogless.

An air operated de-icer 30 is attached to the wing leading edge 10.

The air-operated de-icer 30 typically includes at least one section 32 and a second section 34 affixed to the wing leading edge IO. These parts 32 and 34 are the deicer 30
Points 36, 3 arranged intermittently at intervals along
6', 36". Joint location 36
, 36', 36'' define a tubular pocket structure or passageway between layers 34,32.

Tubular passageways, structures or pockets 38, 38'' typically extend along the leading edge 10 of the wing over a substantial extent of the leading edge of the wing.
It extends in a span along the These pockets or passageways 38, 38' are configured to be inflatable with a fluid under pressure, such as air, as is well known.

In FIG. 1, the pockets or passageways 38, 38' are shown in a collapsed condition.

Referring to FIG. 2, pockets or passageways 38, 38
' is shown in an expanded condition with layer 34 expanded away from the wing leading edge. In this expanded state, any ice adhering to this layer 34 is also expanded and the ice is broken up and removed by the air flow over the leading edge 10.

Referring to FIG. 1, point 40 identifies a deicer material placed at a stagnation point on the leading edge section 10 where air striking the wing's leading edge section 10 is divided to flow above and below the wing. . The velocity of the airflow at this point 40 associated with stagnation approaches zero.

2, as a result of the expansion of the outer layer 34, the outer layer material previously placed at the location 40 associated with the stagnation of FIG. 1 has been expanded away from this location 40. With the material at location 40 in FIG. 2, ice buildup on the wing at stagnation location 40 in FIG. 1 prior to deicer expansion will result in location 40 in FIG. The air stream passing directly over the edge 10 impinges on this ice to dislodge the ice covering the material at point 40 in FIG. It will actually help.

The reason for the arcuate movement of the material shown by point 40 during expansion of the deicer is due to one particular tubular passage 38'.
It is related to the position of 1 and 2, tubular passageway 38' is positioned to asymmetrically encircle the forward portion of wing leading edge section 10. Referring to FIGS. Tubular passage 38'
The width A is from the first joint point 36' to the second joint point 36'.
At least 55% but not more than 75% of this width lies on the essentially planar surface 14, and the remaining width wraps around the intersection 16 and extends over the essentially planar surface 14. 1 and 2. This asymmetrical arrangement of tubular passageways 38' is shown in FIGS.
This creates an arcuate movement of material from the stagnation area on the wing leading edge 10, indicated by location 40 in the figure, causing the air flowing over the wing leading edge 10 to become a scavenge flow as the de-icer expands.

A region of 55% to 75% width of the tubular structure located on one side of this essentially flat surface 12 , 14 is shown at 40 out of the plane created by the wing leading edge section 10 . It is believed that the dewatered air provides the desired upward movement of the material. An asymmetry of less than or greater than the range of 55% to 75% is the point 40 from the plane created by the wing leading edge 10 upon expansion of the tubular structure 38'.
It is believed that the displacement of dewatering material associated with this will be smaller and less desirable. This smaller displacement motion imparts a smaller displacement to the ice accumulated on the intersection 16 and substantially eliminates the removal of the ice accumulation due to the inability to locate the ice accumulation directly in front of the scavenging flow of air. It will cause damage.

The precise selection of the desired degree of asymmetry for the attachment of the tubular portion wrapped around the leading edge is determined somewhat by trial and error. The factors that influence this choice are:
The angle 18, the radius of curvature of the intersection 16, and the degree of bulge of the deicer tubular portion 38' that can withstand the airflow flowing over the leading edge 10. A large displacement movement takes place at a point indicated by 40 in FIGS. 1 and 2 outside the plane created by the leading edge with respect to the air flow flowing over it, resulting in substantial ice formation. It is important to ensure that ice heads that form on the leading edge 10 that are specifically shaped to be concentrated in the area of the leading edge where the ice is removed are removed.

In use, the asymmetrically disposed passageway 38' is first expanded to break up and separate the ice, and then the remaining tubular air passageway 38 is expanded to complete removal of the accumulated ice. In turn, all tubular passages 38, 38' are inflated simultaneously if a sufficient supply of compressed air is available. In other preferred embodiments, the tubular passageway 38' is drawn outwardly along the chord of the leading edge 10 with the remaining passageway 38 on only one of the essentially flat surfaces 12, 14. It is then expanded.

The layers or stacks 32, 34 may be of any suitable or conventional construction. Typical constructions are well known in the art. Typically layers or overlaps 32,3
4 is a junction point 36, 3 between layers or overlaps 32, 34 of fiber reinforcement (not shown) and comprising an elastic portion covering at least one surface of this fiber reinforcement.
6', 36'' can be formed by gluing, sewing, or by the well-known glabellar front.

Sometimes two layers 32 are used to form the tubular section.
, 34 and to facilitate inflation and deflation by promoting air flow through the tubular portion, the tubular structure or tubular structure 38 It is necessary to provide reinforcement or support inside the '.

It is within the scope of the present invention that interconnections of mating tubular sections such that air introduced into one tubular section can be transmitted through it into the next mating tubular section. It is intended that Conventional means for introducing air into the tubular structures 38, 38' are known and used in the practice of the present invention.

Although a preferred embodiment has been illustrated and described in detail, various modifications and changes can be made thereto without departing from the scope of the claims.

[Brief explanation of drawings]

FIG. 1 shows a tapered or knifed leading edge of a wing with a de-icer of the invention mounted in a retracted state, and FIG. It is a figure which shows the expanded state of a deicer. 10... Front edge portion, 12, 14...
Wing surface, 16... Naifetsu (wedge-shaped) leading edge, 3
0...Air-operated deicer, 32, 34...Layer, 36, 36', 36''...Joint point, 38
, 38'...tubular passage, 40...stagnation point. Margin below

Claims (1)

Claims: 1. An air-operated de-icer mounted on an aircraft component where a pair of essentially flat-surfaced aircraft components join to define a wedge shape of the component. the wedge shape is shaped to define a leading edge of the component, the deicer includes at least one pneumatically inflatable tubular structure, the tubular structure comprising: a tubular structure having a length and a width, the length thereof being substantially parallel to the leading edge, the tubular structure being mounted with a length parallel to the leading edge and asymmetrically covering the leading edge;
At least about 50%, but no more than about 75%, of the width of the tubular structure lies on one of the essentially flat surfaces, and the remaining width wraps around the leading edge. An air-operated de-icer located above another essentially flat surface. 2. The de-icer according to claim 1, wherein the component is a wing. 3. The de-icer according to claim 1, wherein the component is a support. 4. An air operated de-icer for application over an aircraft component where a pair of essentially flat surface aircraft components join to define a wedge shape of the component, the wedge The shape is configured to define a leading edge of the component, and the deicers each have a length and a width and extend along the longitudinal direction substantially parallel to the leading edge. a plurality of pneumatically inflatable tubular structures affixed to the component, one of the tubular structures being mounted longitudinally parallel to and asymmetrically covering the leading edge; At least about 55%, but no more than about 75%, of the width of the asymmetrically mounted structure lies on one of the essentially flat surfaces, and the remainder of the width lies around the leading edge. and located on the other of said essentially flat surfaces. 5. The de-icer according to claim 4, wherein the component is a wing. 6. The de-icer according to claim 4, wherein the component is a support. 7. A method for pneumatically deicing an aircraft component presenting a pair of generally flat surfaces shaped to define a wedge-shaped leading edge relative to the airflow flowing over the aircraft. an air-operated de-icer comprising at least one inflatable generally tubular structure having a length and a width, the length of which extends along the leading edge; arranging said tubular structure substantially parallel to said tubular structure, and at least about 55% of said tubular structure
one said expansion such that no more than 5% of said expansion is affixed onto one of said flat surfaces and the remaining width portion wraps around said leading edge and is affixed to the other essentially flat surface; A pneumatic deicing method comprising the steps of: arranging a possible tubular structure and alternately inflating and deflating said tubular structure. 8. The method of claim 7, wherein said component is one of a strut and a wing. 9. The method of claim 7, wherein the plurality of tubular structures are mounted in a laterally spaced configuration generally parallel to and away from the leading edge. 10. In an air-actuated de-icer for an aircraft component that presents a knife-edge leading edge to the airflow flowing over the aircraft during flight, a generally tubular pneumatic actuator disposed over said component. a tubular deicer structure, the length direction of the tubular deicer is substantially parallel to the leading edge;
and at least about 55% of the width of this deicer and about 7
An air-operated de-icer wrapped around the leading edge such that no more than 5% of the width is located on one side of the leading edge and the remainder of the width is located on the other side of the leading edge. 11. The deicer of claim 10, wherein said component is one of a strut and a wing.