Patent Description:
An aircraft includes multiple aircraft control surfaces (also sometimes referred to as flight control surfaces) for controlling aircraft flight. Various types and configurations of aircraft control surfaces and actuators for moving these aircraft control surfaces are known in the art. While these known aircraft control surfaces and actuators have various benefits, there is still room in the art for improvement. There is a need in the art, for example, for lighter weight and/or more compact aircraft control surfaces and/or airfoils to which the aircraft control surfaces are connected.

<CIT> discloses a drive arrangement for flaps and control surfaces of aircraft.

<CIT> discloses control surface actuators.

<CIT> discloses a fluid actuator including a composite cylinder assembly.

According to an aspect of the present invention, there is provided an assembly for an aircraft in accordance with claim <NUM>.

Optional features may be applied to the above aspect in accordance with the appended dependent claims.

<FIG> illustrates an assembly <NUM> for an aircraft such as, but not limited to, an airplane. The aircraft assembly <NUM> includes a stationary aircraft base structure <NUM> and a moveable aircraft control surface <NUM>, which may also be referred to as a flight control surface. The aircraft assembly <NUM> also includes one or more hydraulic actuators <NUM> (one schematically depicted in <FIG>; see also <FIG>) configured to move (e.g., pivot) the aircraft control surface <NUM> relative to the aircraft base structure <NUM>.

The aircraft base structure <NUM> may be configured as an airfoil for the aircraft. The aircraft base structure <NUM> of <FIG>, for example, is configured as an aircraft wing. The present disclosure, however, is not limited to such an exemplary aircraft base structure. The aircraft base structure <NUM>, for example, may alternatively be configured as a horizontal stabilizer, a vertical stabilizer or any other member of the aircraft supporting an aircraft control surface.

The aircraft base structure <NUM> of <FIG> includes an exterior bottom skin <NUM>, an exterior top skin <NUM> and an internal support structure <NUM>. The base structure bottom skin <NUM> forms an exterior bottom aerodynamic flow surface <NUM> of the aircraft base structure <NUM>. The base structure top skin <NUM> forms an exterior top aerodynamic flow surface <NUM> of the aircraft base structure <NUM>. The base structure support structure <NUM> is arranged between the base structure bottom skin <NUM> and the base structure top skin <NUM>. This base structure support structure <NUM> provides an internal rigid frame supporting the base structure bottom skin <NUM> and the base structure top skin <NUM>. The base structure support structure <NUM> of <FIG> extends laterally between and is connected to the base structure bottom skin <NUM> and the base structure top skin <NUM>. This base structure support structure <NUM> may include one or more internal spars, one or more internal stiffeners and/or one or more other structural members.

The aircraft control surface <NUM> is an aerodynamic body configured to adjust, maintain and/or otherwise control one or more flight parameters; e.g., altitude, pitch, roll, etc. The aircraft control surface <NUM> of <FIG>, for example, is configured as an aileron. The present disclosure, however, is not limited to such an exemplary aircraft control surface. The aircraft control surface <NUM>, for example, may alternatively be configured as an elevator, a flap, a rudder or any other flight control surface.

Referring to <FIG>, the aircraft control surface <NUM> extends spanwise along a span line between and to a first end <NUM> of the aircraft control surface <NUM> and a second end <NUM> of the aircraft control surface <NUM>. The aircraft control surface <NUM> extends longitudinally along a chamber line between and to a base <NUM> of the aircraft control surface <NUM> and a tip <NUM> (e.g., a trailing edge) of the aircraft control surface <NUM>. The aircraft control surface <NUM> extends laterally between and to a bottom side <NUM> of the aircraft control surface <NUM> and a top side <NUM> of the aircraft control surface <NUM>.

The aircraft control surface <NUM> of <FIG> includes a bottom skin <NUM>, a top skin <NUM> and an internal support structure <NUM>. The control surface bottom skin <NUM> forms an exterior bottom aerodynamic surface <NUM> of the aircraft control surface <NUM> at the control surface bottom side <NUM>. This control surface bottom skin <NUM> extends spanwise between and to the control surface first end <NUM> and the control surface second end <NUM>. The control surface bottom skin <NUM> extends longitudinally between and to the control surface base <NUM> and the control surface tip <NUM>, where the control surface bottom skin <NUM> meets the control surface top skin <NUM> at the control surface tip <NUM>.

The control surface top skin <NUM> forms an exterior top aerodynamic surface <NUM> of the aircraft control surface <NUM> at the control surface top side <NUM>. This control surface top skin <NUM> extends spanwise between and to the control surface first end <NUM> and the control surface second end <NUM>. The control surface top skin <NUM> extends longitudinally between and to the control surface base <NUM> and the control surface tip <NUM>.

The control surface support structure <NUM> is arranged between the control surface bottom skin <NUM> and the control surface top skin <NUM>. This control surface support structure <NUM> provides an internal rigid frame supporting the control surface bottom skin <NUM> and the control surface top skin <NUM>. The control surface support structure <NUM> of <FIG>, for example, includes one or more internal spars 56A-C (generally referred to as "<NUM>") and one or more internal stiffeners 58A-H (generally referred to as "<NUM>").

Each of the support structure elements <NUM> and <NUM> may extend laterally between and may engage (e.g., contact) the control surface bottom skin <NUM> and the control surface top skin <NUM>. Each of the support structure elements <NUM> and <NUM> may also be connected to (e.g., formed integral with, or mechanically fastened, bonded and/or otherwise fixedly attached to) the control surface bottom skin <NUM> and/or the control surface top skin <NUM>. Each of the internal spars <NUM> of <FIG> extends spanwise along the control surface skins <NUM> and <NUM>, for example between and to (or about) the control surface first end <NUM> and the control surface second end <NUM>. Each of the internal stiffeners <NUM> of <FIG> extends longitudinally along the control surface skins <NUM> and <NUM>, from (or about) the control surface base <NUM> towards (or to) the control surface tip <NUM>.

Referring to <FIG>, the aircraft control surface <NUM> is moveably coupled with the aircraft base structure <NUM>. The aircraft control surface <NUM> of <FIG>, for example, includes one or more hinge mounts <NUM>. Each control surface hinge mount <NUM> of <FIG> is pivotally connected to a respective hinge mount <NUM> of the aircraft base structure <NUM> through a pivot connection <NUM>; e.g., a pin connection. The aircraft control surface <NUM> may thereby pivot between a first position of <FIG> and a second position of <FIG>, or any intermediate position therebetween.

Referring to <FIG>, each hydraulic actuator <NUM> includes a stationary structure <NUM> and a moveable structure <NUM>. The actuator stationary structure <NUM> of <FIG> includes an actuator housing <NUM> and an internal actuator liner <NUM>. The actuator moveable structure <NUM> of <FIG> includes an actuator piston <NUM> and an actuator driver <NUM>.

The actuator housing <NUM> is formed integral with the aircraft control surface <NUM>. The actuator housing <NUM>, more particularly, may be configured as a part of the aircraft control surface <NUM> and its control surface elements <NUM>, <NUM>, <NUM> and <NUM>. The control surface bottom skin <NUM> of <FIG>, for example, at least partially or completely forms a bottom side <NUM> of the actuator housing <NUM>. The control surface top skin <NUM> at least partially or completely forms a top side <NUM> of the actuator housing <NUM>. The control surface spar 56C at least partially or completely forms an internal end <NUM> of the actuator housing <NUM>. A respective one of the control surface stiffeners 58A, 58C of <FIG> forms a first side <NUM> of the actuator housing <NUM>. Another respective one of the control surface stiffeners 58B, 58D forms a second side <NUM> of the actuator housing <NUM>.

The actuator housing <NUM> of <FIG> includes an internal chamber <NUM>. This internal chamber <NUM> of <FIG> extends spanwise within the actuator housing <NUM> / the aircraft control surface <NUM> between and to the housing first side <NUM> and the housing second side <NUM>. The internal chamber <NUM> of <FIG> projects longitudinally into the actuator housing <NUM> / the aircraft control surface <NUM> from the control surface base <NUM> (see <FIG>) to the housing internal end <NUM>. The internal chamber <NUM> of <FIG> extends laterally within the actuator housing <NUM> / the aircraft control surface <NUM> between and to the housing bottom side <NUM> and the housing top side <NUM>.

The actuator liner <NUM> is embedded within the actuator housing <NUM>. More particularly, the actuator liner <NUM> is arranged within and at least partially (or completely) lines the internal chamber <NUM>. The actuator liner <NUM> is fixedly connected to the actuator housing <NUM> / the aircraft control surface <NUM> such that, for example, the actuator liner <NUM> is immovable relative to the actuator housing <NUM> / the aircraft control surface <NUM>. The actuator liner <NUM>, for example, may be interference fit with, bonded to and/or otherwise attached to the actuator housing <NUM>. The actuator liner <NUM> of <FIG> is configured as a hydraulic cylinder (or a sleeve) for the actuator piston <NUM>. This actuator liner <NUM> has an internal bore which at least partially completely forms an internal cavity <NUM> of the hydraulic actuator <NUM>.

The actuator piston <NUM> is arranged within the internal bore and the internal cavity <NUM>. The actuator piston <NUM> is configured to move axially within the internal cavity <NUM> along an axial centerline of the hydraulic actuator <NUM> between a first (e.g., retracted) position of <FIG> (e.g., corresponding to surface portion of <FIG>) and a second (e.g., extended) position of <FIG> (e.g., see corresponding to surface position of <FIG>), or any axial position therebetween. The actuator piston <NUM> of <FIG> fluidly divides the internal cavity <NUM> into a first sub-cavity 92A and a second sub-cavity 92B. The first sub-cavity 92A is fluidly coupled with a first hydraulic fluid passage 94A through a sidewall of the actuator housing <NUM> and a sidewall of the actuator liner <NUM>, which first hydraulic fluid passage 94A is fluidly coupled with a conduit (not shown). The second sub-cavity 92B is fluidly coupled with a second hydraulic fluid passage 94B through the housing sidewall and the liner sidewall, which second hydraulic fluid passage 94B is fluidly coupled with a conduit (not shown). To move the actuator piston <NUM> from its first position of <FIG> to its second position of <FIG>, hydraulic fluid may be directed (e.g., pumped) into the first sub-cavity 92A through the first hydraulic fluid passage 94A and extracted (e.g., drawn out) from the second sub-cavity 92B through the second hydraulic fluid passage 94B (see <FIG>). To move the hydraulic actuator <NUM> from its second position of <FIG> to its first position of <FIG>, the hydraulic fluid may be directed (e.g., pumped) into the second sub-cavity 92B through the second hydraulic fluid passage 94B (see <FIG>) and extracted (e.g., drawn out) from the first sub-cavity 92A through the first hydraulic fluid passage 94A.

The actuator driver <NUM> of <FIG> may include an actuator ram <NUM> (e.g., a shaft) and an actuator linkage <NUM>; e.g., a fixed length link such as a tie rod. The actuator ram <NUM> is connected to the actuator piston <NUM>. The actuator ram <NUM> projects axially out from the actuator piston <NUM> along the axial centerline to a distal end of the actuator ram <NUM>. The actuator ram <NUM> is motively coupled to the aircraft base structure <NUM>. The actuator ram <NUM> of <FIG>, for example, is moveably coupled to the base structure support structure <NUM> through the actuator linkage <NUM>. More particularly, the actuator ram <NUM> is pivotally connected to the actuator linkage <NUM> at (e.g., on, adjacent or proximate) the ram distal end and/or a first end of the actuator linkage <NUM> through a pivot connection <NUM>; e.g., a pin connection. The actuator linkage <NUM> is pivotally connected to a (e.g., stationary) mount <NUM> of the base structure support structure <NUM> at a second end of the actuator linkage <NUM> through a pivot connection <NUM>; e.g., a pin connection. The present disclosure, however, is not limited to such an exemplary actuator driver configuration. For example, in other embodiments, the actuator driver <NUM> may include one or more additional drive elements and/or the actuator linkage <NUM> may be omitted.

With the foregoing arrangement, complexity and/or weight of the aircraft assembly <NUM> may be reduced as compared to another system where an actuator is a discrete severable component from an aircraft control surface. Furthermore, integrating the hydraulic actuator <NUM> into the aircraft control surface <NUM> may facilitate providing the aircraft base structure <NUM> and/or the aircraft control surface <NUM> with smaller dimensions and, thus, a more compact and/or lightweight form.

The aircraft assembly <NUM> is described above using the terms bottom and top with reference to the orientation in the drawings for ease of description. The aircraft assembly <NUM> of the present disclosure, however, is not limited to any particular spatial orientations relative to gravity. For example, in other embodiments, the skin <NUM> may be gravitationally above the skin <NUM>. In still other embodiments, the skins <NUM> and <NUM> may be gravitationally next to each other; e.g., the aircraft assembly <NUM> of <FIG> may be rotated ninety degrees.

Claim 1:
An assembly (<NUM>) for an aircraft, comprising:
an aircraft control surface (<NUM>); and
a hydraulic actuator (<NUM>) including a housing (<NUM>) and a piston (<NUM>) within the housing (<NUM>), the housing (<NUM>) formed integral with the aircraft control surface (<NUM>),
characterised in that:
the aircraft control surface (<NUM>) comprises an internal stiffener (<NUM>) extending along a camber line of the aircraft control surface (<NUM>) and a portion of the housing (<NUM>) is formed by the internal stiffener (<NUM>), and the internal stiffener (<NUM>) extends longitudinally from a base (<NUM>) of the aircraft control surface (<NUM>) to a tip (<NUM>) of the aircraft control surface (<NUM>).