Patent Description:
A flap is a high lift device typically consisting of a hinged panel or panels mounted on an aircraft wing, such as the trailing edge of the wing. The flap's setting (e.g., the position and orientation of the flap relative to the wing) can be adjusted to increase the camber and, in some applications, the chord and surface area of the wing. The wing's camber can indicate the convexity of the upper part of the wing and the concavity of the lower part of the wing. Extending flaps during flight can increase lift and drag while also reducing stall speed, which can improve the aircraft's performance during takeoffs and landings. During a landing, the extended flaps enable the aircraft to travel at lower landing speeds that can reduce the length of the landing strip required. Extended flaps can also increase drag, which enables the aircraft to steepen its descent angle without increasing overall airspeed.

The configurations of the flaps can vary across different types of aircrafts. For instance, large jetliners are often designed with flaps that have multiple portions (e.g., three part flaps) while smaller aircrafts have appropriately sized flaps that attach to the wings via hinges. To adjust the settings of the flaps, flap mechanical systems are built into the wings, which can include actuators to extend or retract the flaps to effectively change the profiles and surface areas of wings. In addition to the actuators, flap mechanical systems can also incorporate auxiliary support structures can help stabilize and align the flaps during different settings.

<CIT> states, according to its abstract, a landing flap system in an aircraft wing, including an upper and a lower track and a drive for a tandem, flap moving carriage, being composed of an inner carriage having a plurality of rollers for running on the upper track and an outer carriage having at least two rollers for running on the lower track; a hinge pin interconnects the carriages and connects them to the landing flap; a second hinge connects the outer carriage to the landing flap; a thrust and tension rod hingedly connects the outer carriage to the drive; and further rollers are arranged at an acute angle to an axis that extends vertically to such axes and to an axis that is parallel to the longer internal axis of the craft, the further rollers balancing the carriages.

<CIT> states, according to its abstract, an actuation and extension mechanism for aerodynamically high-lift devices such as a wing leading edge slat or a wing trailing edge flap; wherein an aerodynamic panel is connected to one end of an extendible track member that is supported and guided by its other end through rollers fixedly mounted to wing rib structure. The track member incorporates a separate rack gear segment internally thereof as part of the extension or retraction mechanism and this combination of track and gear segment provides the primary support and drive means to the high-lift device.

According to a first aspect, there is provided a flap assembly as defined in claim <NUM>. According to a second aspect, there is provided a system as defined in claim <NUM>. According to a third aspect, there is provided an aircraft as defined in claim <NUM>. Optional features of aspects are set out in the dependent claims.

The novel features believed characteristic of the illustrative examples are set forth in the appended claims. The illustrative examples, however, as well as a preferred mode of use, further objectives and descriptions thereof, will best be understood by reference to the following detailed description of an illustrative example of the present disclosure when read in conjunction with the accompanying drawings, wherein:.

Disclosed examples will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all of the disclosed examples are shown. Indeed, several different examples may be described and should not be construed as limited to the examples set forth herein. Rather, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.

Example embodiments relate to different configurations of a flap assembly with a jam resistant flap track. Aircrafts can incorporate disclosed flap assemblies within flap mechanical systems to use for auxiliary stabilization and support for flaps in addition to the actuators that extend or retract the flaps. The disclosed flap assemblies are designed with mechanical features that reduce manufacturing complexity while also increasing resistance to potential jams during operation. As an example result, an aircraft's flap mechanical systems can incorporate disclosed flap assemblies instead of alternative options that are typically prone to jams and can cost more time and resources to manufacture. Jams can also drive additional cost and weight to the final design of the aircraft, which impacts customers that use the aircraft. Flaps that are not prone to jam can result in lower maintenance costs during normal operation. For instance, a flap mechanical system can use two actuators positioned near the ends of a flap and one or more disclosed flap assemblies positioned in between the actuators to provide further stabilization and alignment during flap deflection.

Referring now to the Figures, <FIG> illustrates an aircraft <NUM> configured with flap mechanical systems that enable flap deflection during operation. In the example embodiment, the aircraft <NUM> includes two aircraft wings <NUM> with each wing <NUM> having multiple flaps labeled as a flap 104A, a flap 104B, and a flap 104C. In order to enable computing devices on the aircraft <NUM> to adjust the flaps 104A-104C during operations, each flap 104A-104C is connected to a flap mechanical system that is built into the aircraft wings <NUM> and can be used to reposition the flaps 104A-104C relative to the aircraft wing <NUM>. For illustration purposes, the flap mechanical system <NUM> is outlined in <FIG> to enable further description of how a mechanical system may be implemented and arranged to modify the position of the flap 104B on each aircraft wing <NUM>. Flaps 104A, 104C can similarly have flap mechanical systems (not outlined), which may operate collectively with the flap mechanical system <NUM> and/or independently during aircraft operations.

The aircraft <NUM> represents an example fixed-wing aircraft that may use flaps 104A-104C during operations, which can increase performance during takeoff and landing. When the flaps 104A-104C are positioned in an up orientation, the camber of the aircraft <NUM> enables the aircraft wings <NUM> to produce more lift. Depending on the aircraft <NUM>, the flap 104B may extend to various degrees. For instance, the aircraft <NUM> may extend the flap 104B approximately <NUM> degrees during takeoff and <NUM> degrees during landing. After liftoff, the aircraft <NUM> may retract the flaps 104A-104C to avoid drag. As such, deploying the flaps 104A-104C can increase lift, which allows the aircraft <NUM> to climb during takeoff at slow speeds and also safely descend during landing also at slow speeds.

To adjust the settings of the flaps 104A-104C, aircraft computing devices may transmit signals to actuators positioned within the aircraft wings <NUM>. For instance, the flap mechanical system <NUM> can include one or multiple flap actuators that generate force to adjust the setting of the flap 104B. As an example embodiment, the flap mechanical system <NUM> can incorporate the main flap support <NUM> illustrated in <FIG> and <FIG>, which can use an actuator <NUM> to extend or retract the flap 104B.

As shown in <FIG> and <FIG>, the main flap support <NUM> represents a typical mechanical system that can be implemented on aircrafts to adjust the setting of a flap. For instance, the aircraft <NUM> can incorporate multiple main flap supports <NUM> into flap mechanical systems on the aircraft wings <NUM>, including the flap mechanical systems <NUM> that enables deflection of the flaps 104B. In the example, the main flap support <NUM> is configured with an actuator <NUM> that can move a flap carriage <NUM> along a track <NUM>. In practice, the main flap support <NUM> is secured at a fixed position to the aircraft wing <NUM> via coupling component <NUM> and coupling component <NUM> while the flap carriage <NUM> is coupled to the flap 104B at coupling points <NUM>. With this arrangement, the actuator <NUM> can then adjust the setting of the flap 104B relative to the aircraft wing <NUM> by changing the position of the flap carriage <NUM> on the track <NUM> via the trapped rollers <NUM> connecting the flap carriage <NUM> onto the track <NUM>. For instance, the actuator <NUM> can be used to extend or retract the flap 104B, which adjusts the profile and surface area of the aircraft wing <NUM> to enable efficient flight at low airspeeds. In some embodiments, the actuator <NUM> is a lead screw type of mechanism driven by an electric or hydraulic motor that can be activated to extend or retract the flap 104B based on signals received from an aircraft computing system.

The track <NUM> is shown as a Pi-section beam built with a failsafe bar <NUM> as depicted in the cutaway view illustrated in <FIG>. The Pi-section configuration enables trapped rollers <NUM> to rotate in the channels formed between the top surface and the bottom surface of the track <NUM>, which allows the flap carriage <NUM> to change the setting of the flap 104B. The Pi-section configuration, however, is difficult to manufacture due to the precise size and shape requirements to form the Pi-section. In addition, manufacturing the track <NUM> also requires additional time to produce and incorporate the failsafe bar <NUM>. Machining the deep center slot in hardened steel of the track <NUM> for the failsafe bar <NUM> can be challenging. Fitting and installing the failsafe bar <NUM> into the slot formed in the track <NUM> also adds further complexity to the manufacturing process.

Furthermore, the pins <NUM> for the trapped rollers <NUM> require a specific alignment in the flap carriage <NUM> to allow the trapped rollers <NUM> to smoothly rotate within the grooves of the Pi-section structure of the track <NUM>. In some cases, this alignment might result in a jam that can damage operations of the main flap support <NUM>.

Flap mechanical systems can also incorporate auxiliary supports to supplement the actuators. <FIG>, <FIG> illustrates different views of a flap assembly <NUM>, which may be used to supplement one or more main flap supports <NUM> within a flap mechanical system (e.g., the flap mechanical system <NUM> associated with the flap 104B). The other flaps 104A, 104C shown on the aircraft wings <NUM> of the aircraft <NUM> can similarly be adjusted by flap mechanical systems that incorporate the disclosed flap assembly <NUM>. In practice, the actuators <NUM> of the main flap supports <NUM> (or similar devices) may supply the force to adjust the setting of the attached flap 104B while the flap assembly <NUM> provides additional support and stabilization to the flap 104B at the different settings.

The different views of the disclosed flap assembly <NUM> illustrated in <FIG> show the mechanical features of the flap assembly <NUM>. In the example embodiment, the flap assembly <NUM> includes a track <NUM> and a flap carriage <NUM> that is configured to move along the track <NUM> using a roller interface <NUM> similar to the main flap support <NUM>. In addition, the flap assembly <NUM> is shown with a coupling component <NUM> for connecting the track <NUM> at a fixed position on an aircraft wing (e.g., built into the aircraft wing <NUM> of the aircraft <NUM>) while the top portion <NUM> of the flap carriage <NUM> is configured to connect to the bottom surface of the flap 104B.

As such, the example configuration of the flap assembly <NUM> illustrated in <FIG> represents one possible configuration. Other example configurations for the flap assembly <NUM> are possible. For instance, the sizes, the materials used (e.g., types of metals, alloys, and rubber), and the arrangement of the mechanical components of the flap assembly <NUM> can differ in other example embodiments. For instance, parameters of the track <NUM> and/or other components of the flap assembly <NUM> can vary based on the type of aircraft that incorporates the flap assembly <NUM>.

Similar to the main flap support <NUM> shown in <FIG>, the flap assembly <NUM> can be used to provide support and alignment to a flap (e.g., the flap 104B) at different settings during aircraft operations. Unlike the main flap support <NUM>, however, the flap assembly <NUM> lacks an actuator in the example embodiment and may therefore provide passive support that depends on actuation by other support systems (e.g., the actuator <NUM> of the main flap support <NUM>) to adjust the position of the flap 104B. For example, the flap mechanical system <NUM> can have two main flap supports <NUM> positioned near the ends of the flap 104B and the flap assembly <NUM> positioned in the middle of the flap 104B.

The mechanical designs of the components of the flap assembly <NUM> decrease overall manufacturing complexity while also reducing vulnerability to potential jams that might arise during flap deflection. In practice, the combination of the track <NUM> and the roller interface <NUM> on the flap carriage <NUM> enable jam-resistant performance that can supplement actuators within flap mechanical systems. Similar to the track <NUM> of the main flap support <NUM>, the track <NUM> is a support beam with an elongate structure that can be coupled to an aircraft wing (e.g., aircraft wing <NUM> of aircraft <NUM>) at a fixed position via the coupling component <NUM> located on an upper portion of the track <NUM> and/or other different potential coupling mechanisms. These coupling components can have various forms within example embodiments. Further, unlike the Pi-section configuration of the track <NUM>, the track <NUM> is shown with a simple design, which is made up of sub-tracks 402A, 402B. Each sub-track 402A, 402B has a C-channel configuration, which results in the track <NUM> having a similar structure as the Pi-section configuration of the track <NUM> when the sub-tracks 402A, 402B are coupled together at seam <NUM> in a back-to-back configuration as further shown in <FIG> and <FIG>.

In addition, unlike the Pi-section configuration of the track <NUM>, sub-track 402A and sub-track 402B can be individually manufactured before being coupled together via one or more types of fasteners, such as bolts and screws, adhesives, welding, and/or a combination thereof. As an example result, each of the sub-tracks 402A, 402B have the physical properties to operate individually if needed, which increases crack resistance of the track <NUM> overall while also eliminating the need for a failsafe bar. This further reduces manufacturing complexity by eliminating a part (i.e., the failsafe bar) and additional steps during production of the track <NUM>.

The track <NUM> can be made out of various materials within example embodiments, such as metals and/or metallic alloys. In addition, parameters of the track <NUM> can depend on the type of aircraft <NUM> that is incorporating the flap assembly <NUM>. As shown in <FIG>, the length <NUM> of the track <NUM> is greater than the width <NUM> of the track <NUM>, which accommodates the structures of the aircraft wing <NUM> and the flap 104B. The length <NUM> and overall structure of the track <NUM> can allow deflection of the flap 104B at different settings used during aircraft operations. In practice, the track <NUM> is configured to couple to the aircraft wing <NUM> via the coupling component <NUM> such that the length <NUM> of the track <NUM> extends approximately parallel to a path of travel by the aircraft <NUM>.

As further shown in <FIG>, the elongate structure of the track <NUM> includes a curved end <NUM> designed to enable deflection of the flap 104B relative to the aircraft wing <NUM>. In response to actuation from the main flap support <NUM>, the flap carriage <NUM> can be moved along the curved end <NUM> of the track <NUM> to secure the flap 104B up to its full angular deflection relative to the aircraft wing <NUM> (e.g., up to <NUM> degrees).

The flap carriage <NUM> is shown coupled to the track <NUM> and includes a roller interface <NUM> that enables the flap carriage <NUM> to move along a portion of the length <NUM> of the track <NUM>. The flap 104B can rotate about the roller interface <NUM> while the roller interface <NUM> translates. In the example embodiment shown in <FIG>, the flap carriage <NUM> is a three piece back-to-back carriage, which increases durability of the flap carriage <NUM> overall while also reducing the complexity of manufacturing the flap carriage <NUM>. In particular, <FIG> illustrate the combination of a side portion 610A, a middle portion 610B, and another side portion 610C that are coupled together to form the flap carriage <NUM>. Each of the side portions 610A, 610C has an L-shape configuration while the middle portion 610B is shown with an inverted U-channel configuration. The three portions can be coupled together via one or more types of fasteners to form the flap carriage <NUM>. In particular, the side portion 610A is coupled to the middle portion 610B forming seam <NUM> and the side portion 610C is coupled to the opposite side of the middle portion 610B forming seam <NUM>.

This three-portion configuration for the flap carriage <NUM> reduces the manufacturing complexity of the flap carriage <NUM>. In addition, the inverted U-channel of the middle portion 610B can be structured to securely fit around the track <NUM> with minor gaps <NUM> that enables the flap carriage <NUM> to move along a portion of the length <NUM> of the track <NUM> as the track <NUM> operates as the support beam for the flap assembly <NUM>. In some embodiments, the components of the flap carriage <NUM> can be created via additive manufacturing or another type of manufacturing process.

The top portion <NUM> of the flap carriage <NUM> is shown coupled to the flap 104B such that movement of the flap carriage <NUM> along the length <NUM> of the track enables movement of the flap 104B relative to the aircraft wing <NUM>. As such, the top portion <NUM> can be connected via one or more types of fasteners, such as bolts, screws, adhesives, etc..

The roller interface <NUM> coupled into the flap carriage <NUM> enables the flap carriage <NUM> to adjust position on the track <NUM>. As shown in the example embodiment, the roller interface <NUM> includes a primary roller <NUM> and a pair of secondary rollers 604A, 604B, which are all positioned within the inverted U-channel of the middle portion 610B of the flap carriage <NUM>. When the flap assembly <NUM> is installed, the track <NUM> is configured to be positioned in the inverted U-channel of the middle portion 610B such that a bottom surface <NUM> of the track <NUM> engages the primary roller <NUM> (e.g., sits on top of the primary roller <NUM>) and the grooves in the C-channel of each sub-track 402A, 402B are aligned relative to the pair of secondary rollers 604A, 604B, respectively. This enables the secondary rollers 604A, 606B to rotate within the grooves in the outward-facing C-channels of the track <NUM> while the bottom surface <NUM> of the track <NUM> moves along with assistance from the primary rollers <NUM>.

To further illustrate, the cut away view of the flap assembly <NUM> shown in <FIG> depicts the secondary roller 604A positioned in the groove of the C-channel formed in sub-track 402A and the secondary roller 604B positioned in the groove of the C-channel formed in the sub-track 402B. In such positions, the secondary rollers 604A-604B can rotate in the grooves of the C-channels that are part of the track <NUM> while the primary roller <NUM> provides support and enables movement of the flap carriage <NUM> along the track <NUM>.

The roller interface <NUM> of the flap carriage <NUM> differs from the rollers <NUM> of the flap carriage <NUM> of the main flap support <NUM>. As shown in the example embodiment, the primary roller <NUM> and the pair of secondary rollers 604A, 604B are arranged to reduce potential jams during movement of the flap carriage <NUM> along the track <NUM>. The primary roller <NUM> is shown positioned below the track <NUM>, which enables potential foreign object debris to fall out of the flap carriage <NUM> rather than causing potential jams. In addition, the secondary rollers 604A, 604B can be implemented using dead weight rollers designed with pins 608A, 608B that are able to fuse when the associated secondary roller 604A, 604B encounters any web or flange jam.

To secure the primary roller <NUM> in position in the inverted U-channel of the flap carriage <NUM>, the primary roller <NUM> is positioned on a pin <NUM>. In addition, the secondary roller 604A is shown positioned on a pin 608A and the secondary roller 604B is shown positioned on a pin 608B. In some embodiments, the secondary rollers 604A-604B can be implemented as two dead weight rollers.

The pin <NUM> of the primary roller <NUM> positions the primary roller <NUM> in the inverted U-channel of the middle portion 610B and is shown extending from the side portion 610A to the side portion 610C. In addition, the pin <NUM> is shown positioned near the bottom end 616B of the side portion 610A (opposite the top side 616A of the side portion 610A) and near the bottom end 618B of the side portion 610C (opposite the top side 618A of the side portion 610C). At this position, the primary roller <NUM> can rotate with respect to the bottom surface <NUM> of the track <NUM>. In some examples, the primary roller <NUM> is an air-loaded roller to further support the track <NUM> during movement of the flap carriage <NUM>.

As further shown, the secondary roller 604A is positioned on an inner surface and near the middle of the side portion 610A and the secondary roller 604B positioned on an inner surface and near the middle of the side portion 610C. This enables the secondary rollers 604A, 604B to be positioned in a manner that extend toward each other in an alignment on a given plane. With this arrangement, the secondary roller 604A is configured to couple to a first side of the track <NUM> (i.e., the inner groove of the C-channel of sub-track 402A) and the secondary roller 604B is configured to couple to a second side of the track <NUM> (i.e., the inner groove of the C-channel of the sub-track 402B). The secondary rollers 604A, 604B are shown arranged in a redundant configuration to further enhance performance of the flap assembly <NUM>.

In addition, <FIG> also further shows that the flap carriage <NUM> includes an inner pad <NUM> configured to protect the top surface <NUM> of the track <NUM>. For instance, the inner pad <NUM> can engage and protect the track <NUM> if a malfunction occurs at one or both of the pair of secondary rollers 604A, 604B. The inner pad <NUM> is configured to act as a load path in the event the flap 104B and track <NUM> contact. The secondary rollers 604A, 604B can be dead weight rollers in some embodiments. The dead weight rollers can take minor flap loads while taxiing on the runway. By using two deadweight rollers, the remaining roller takes limit load until the next maintenance check. In instances where both of the secondary rollers 604A, 604B break, the inner pad <NUM> provides cushion to the top surface <NUM> of the track <NUM> to continue normal operation. This failure may likely cause a flap misfair (e.g., misalignment due to component failure) that is visible during any inspection of the aircraft. As further shown in <FIG>, the pin <NUM> of the primary can have a pin-in-pin configuration made up of interior pin <NUM> and exterior pin <NUM>, which increases durability of the pin <NUM> and the primary roller <NUM> for fail safety. The pin-in-pin configuration of the pin <NUM> allows either of the interior pin <NUM> and the exterior pin <NUM> to take limit load if other pin cracks. This increases overall durability of the primary roller <NUM> during operations.

By the term "substantially" or "about" used herein, it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, measurement error, measurement accuracy limitations, friction, and other factors known to skill in the art, may occur in amounts that do not preclude and/or occlude the effect the characteristic was intended to provide.

Claim 1:
A flap assembly (<NUM>) comprising:
a track (<NUM>) having an elongate structure, wherein the track (<NUM>) is configured to couple to an aircraft wing (<NUM>); and
a flap carriage (<NUM>) configured to move along a length (<NUM>) of the track (<NUM>); wherein:
the flap carriage (<NUM>) includes a primary roller (<NUM>) and a pair of secondary rollers (604A, 604B) configured to secure the flap carriage (<NUM>) to the track (<NUM>);
a top portion (<NUM>) of the flap carriage (<NUM>) is configured to couple to a flap (104A-104C) such that movement of the flap carriage (<NUM>) along the length (<NUM>) of the track (<NUM>) enables movement of the flap (104A-104C) relative to the aircraft wing (<NUM>);
the flap carriage (<NUM>) includes an inverted U-channel formed by the top portion (<NUM>) and side portions (610A, 610C) of the flap carriage (<NUM>);
the primary roller (<NUM>) and the pair of secondary rollers (604A, 604B) are positioned inside the inverted U-channel;
the side portions (610A, 610C) of the flap carriage (<NUM>) include a first side portion (610A) having a first end and a second end and a second side portion (610C) having a first end and a second end;
the first end of the first side portion (610A) and the first end of the second side portion (610C) are coupled to the top portion (<NUM>) of the flap carriage (<NUM>);
a pin (<NUM>) positions the primary roller (<NUM>) inside the inverted U-channel, the pin (<NUM>) extending through the first side portion (610A) proximate the second end of the first side portion (610A) and through the second side portion (610C) proximate the second end of the second side portion (610C); and
the position of the pin (<NUM>, 608A, 608B) of the primary roller (<NUM>) enables the primary roller (<NUM>) to couple to a bottom surface (<NUM>) of the track (<NUM>, <NUM>).