Patent Description:
A modern aircraft propulsion system includes a gas turbine engine housed within a nacelle. The nacelle may include cowl doors to provide access to various components configured with the gas turbine engine. Various types and configurations of cowl doors are known in the art. Furthermore, various techniques are known in the art for removably coupling those cowl doors to a fixed structure. While these known cowl doors and coupling techniques have various benefits, there is still room in the art for improvement.

There is a need in the art for improved cowl doors and cowl door coupling assemblies.

<CIT> discloses a structural seam fastener.

<CIT> discloses a ducted fan turbine engine nozzle assembly.

<CIT> discloses a method for making a composite panel and a resulting panel.

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

The following optional features may be applied to any of the above aspects.

The cellular core may be bonded to the inner skin and/or the outer skin.

The cellular core may be configured as or otherwise include a honeycomb core.

The first cellular core may have a first density. The second cellular core may have a second density that is different than (or equal to) the first density.

The structural panel may also include an inner reinforcement sheet and/or an outer reinforcement sheet. The inner reinforcement sheet may be bonded to and/or arranged between the cellular core and the inner skin. The outer reinforcement sheet may be bonded to and/or arranged between the cellular core and the outer skin.

The structural panel may be configured from or otherwise include metal.

A turbine engine case may be included. The turbine engine case may be configured with a receptacle. The coupler may be configured to project into and mate with the receptacle when the cowl door is in the closed position.

A seal element may be included. The seal element may be attached to the base and configured to press against the turbine engine case.

A reinforcement sheet may be included. The reinforcement sheet may be bonded to and arranged between the base and the inner skin or the outer skin.

The reinforcement sheet may be bonded to the cellular core.

The mount may be configured as a monolithic body.

The mount may be configured as or otherwise include metal.

The mount may be bonded to the inner skin and/or the outer skin.

The base may have a generally U-shaped cross-sectional geometry.

The base may include an inner flange, an outer flange and a web. The web may extend between and/or may be connected to the inner flange and the outer flange. The inner flange may be overlapped by and/or connected to the inner skin. The outer flange may be overlapped by and/or connected to the outer skin.

The present invention may include any one or more of the individual features disclosed above and/or below.

<FIG> illustrates an aircraft propulsion system <NUM> for an aircraft such as, but not limited to, a commercial airliner or a cargo plane. The propulsion system <NUM> includes a nacelle <NUM> and a gas turbine engine. This gas turbine engine may be configured as a high-bypass turbofan engine. Alternatively, the gas turbine engine may be configured as any other type of gas turbine engine capable of propelling the aircraft during flight.

The nacelle <NUM> is configured to house and provide an aerodynamic cover for the gas turbine engine. The nacelle <NUM> of <FIG> includes a nacelle outer structure <NUM> and a nacelle inner structure <NUM>, which inner structure <NUM> may sometimes be referred to as an inner fixed structure (IFS).

Referring to <FIG>, the inner structure <NUM> covers at least an axial portion (or an entirety) of a core <NUM> of the gas turbine engine, which engine core <NUM> may include a compressor section, a combustor section and a turbine section. The inner structure <NUM> includes an inner barrel <NUM> and at least one bifurcation structure <NUM>; e.g., an upper bifurcation cowl. The inner barrel <NUM> may be a generally cylindrical / barrel-shaped cowl that extends circumferentially around and axially along the engine core <NUM> and an axial centerline <NUM> (e.g., rotational axis) of the aircraft propulsion system <NUM>. The inner barrel <NUM> at least partially forms an internal compartment <NUM> (e.g., a core compartment) within the nacelle <NUM>. This internal compartment <NUM> at least partially or completely houses the engine core <NUM>; e.g., the engine core <NUM> is arranged within the internal compartment <NUM>. The bifurcation structure <NUM> provides an aerodynamic housing for a pylon <NUM> which mounts the aircraft propulsion system <NUM> to the aircraft. The bifurcation structure <NUM> extends radially between the inner barrel <NUM> and the outer structure <NUM>.

The outer structure <NUM> covers a fan section (not shown) of the gas turbine engine. The outer structure <NUM> covers at least a forward portion of the inner structure <NUM> and its inner barrel <NUM> so as to form a bypass duct and an associated bypass flowpath <NUM> radially between the structures <NUM> and <NUM>. The outer structure <NUM> may also be configured with a thrust reverser (not shown) for redirecting airflow from the bypass flowpath <NUM> out of the nacelle <NUM> in a forward and/or outward direction. The present disclosure, however, is not limited to the foregoing exemplary general nacelle configuration.

Briefly, the bypass duct of <FIG> is configured as an O-Duct. The term "O-duct" may describe a duct through which only a single bifurcation extends between and connects a nacelle outer structure and a nacelle inner structure. By contrast, the term "C-Duct" or "D-duct" may describe a duct through which two bifurcations (e.g., an upper bifurcation and a lower bifurcation) extend between and connect a nacelle outer structure and a nacelle inner structure. Of course, although the exemplary duct shown in <FIG> is an O-duct, the present disclosure is not limited to any particular duct configurations. In particular, the present disclosure also contemplates the nacelle <NUM> having a C-duct or a D-duct.

Referring still to <FIG>, the inner structure <NUM> may be configured with one or more movable (e.g., pivotable) inner structure components <NUM>. These inner structure components <NUM> may be configured as or otherwise include inner cowl doors <NUM>. Each of these inner cowl doors <NUM> extends circumferentially about the centerline <NUM> and the engine core <NUM>. In particular, each inner cowl door <NUM> extends circumferentially between an inner cowl upper end <NUM> and an inner cowl lower end <NUM>. The inner cowl upper end <NUM> may be pivotally connected to the bifurcation structure <NUM> and/or the pylon <NUM> by, for example, one or more hinges. Each inner cowl door <NUM> is thereby operable to move (e.g., pivot) between a closed position (position of <FIG>) and an open position (position of <FIG>). Referring again to <FIG>, the inner cowl lower ends <NUM> of the inner cowl doors <NUM> may be configured to latch together via one or more latches so as to at least partially or completely form the inner barrel <NUM>.

The outer structure <NUM> may be configured with one or more movable (e.g., pivotable) outer structure components <NUM>. These outer structure components <NUM> may be configured as or otherwise include outer cowl doors <NUM>. Each of these outer cowl doors <NUM> extends circumferentially about the centerline <NUM>. In particular, each outer cowl door <NUM> extends circumferentially between an outer cowl upper end <NUM> and an outer cowl lower end <NUM>. The outer cowl upper end <NUM> may be pivotally connected to the bifurcation structure <NUM> and/or the pylon <NUM> by, for example, one or more hinges. Each outer cowl door <NUM> is thereby operable to move (e.g., pivot) between a closed position (position of <FIG>) and an open position (position of <FIG>). Referring again to <FIG>, the outer cowl lower ends <NUM> of the outer cowl doors <NUM> may be configured to latch together via one or more latches so as to at least partially or completely form, for example, a fan cowl and/or a translatable sleeve of the outer structure <NUM>.

<FIG> illustrates an end portion of an assembly <NUM> for the aircraft propulsion system <NUM>. This aircraft propulsion system assembly <NUM> includes a fixed structure <NUM> and a moveable (e.g., pivotable) structure <NUM> such as a cowl door <NUM>. This cowl door <NUM> may be configured as one of the inner cowl doors <NUM>. Alternatively, the cowl door <NUM> may be configured as one of the outer cowl doors <NUM>, or any other moveable structure included in the aircraft propulsion system <NUM>; e.g., a fan cowl door.

The fixed structure <NUM> of <FIG> is configured as a turbine engine case. This fixed structure <NUM> includes a tubular (or arcuate) sidewall <NUM> which extends circumferentially about (or completely around) the centerline <NUM>. The fixed structure <NUM> also includes a mount <NUM> with a receptacle <NUM> such as, but not limited to, a groove; e.g., a V-groove. This receptacle <NUM> of <FIG> projects partially radially into the mount <NUM>. The receptacle <NUM> also extends circumferentially about the centerline <NUM> within, through or into the mount <NUM>.

The cowl door <NUM> of <FIG> includes a structural panel <NUM>, a cowl door mount <NUM> and a seal element <NUM>; e.g., a fire seal element and/or a bulb seal element. The structural panel <NUM> includes a first (e.g., inner) skin <NUM>, a second (e.g., outer) skin <NUM> and one or more cellular cores <NUM> and <NUM>. The structural panel <NUM> of <FIG> also includes one or more reinforcement sheets <NUM> and <NUM>.

Referring to <FIG>, the first cellular core <NUM> is configured to form one or more first cavities <NUM> (e.g., radially) between the first skin <NUM> and the second skin <NUM> and, more particularly, between the first (e.g., inner) reinforcement sheet <NUM> and the second (e.g., outer) reinforcement sheet <NUM>. The first cellular core <NUM> of <FIG>, for example, is configured as a honeycomb core. This first cellular core <NUM> includes a plurality of corrugated first sidewalls <NUM>. The first sidewalls <NUM> are arranged in a side-by-side array and connected to one another such that each adjacent (neighboring) pair of first sidewalls <NUM> forms an array of the first cavities <NUM> therebetween. Referring to <FIG>, each of the first cavities <NUM> extends (e.g., generally radially) through the first cellular core <NUM> to and between the first reinforcement sheet <NUM> and the second reinforcement sheet <NUM>. Referring to <FIG>, each first cavity <NUM> may have a polygonal (e.g., hexagonal) cross-sectional geometry when viewed in a plane parallel to one or more of the elements <NUM>, <NUM>, <NUM> and/or <NUM> (see <FIG>). The present disclosure, however, is not limited to any particular cellular core configurations. The present disclosure is also not limited to including reinforcement sheets. One or both of the reinforcement sheets <NUM> and <NUM>, for example, may be omitted such that the first cellular core <NUM> is connected directly to the first skin <NUM> and/or the second skin <NUM>.

Referring to <FIG>, the second cellular core <NUM> is configured to form one or more second cavities <NUM> (e.g., radially) between the first skin <NUM> and the second skin <NUM>. The second cellular core <NUM> of <FIG>, for example, is configured as a honeycomb core. This second cellular core <NUM> includes a plurality of corrugated second sidewalls <NUM>. The second sidewalls <NUM> are arranged in a side-by-side array and connected to one another such that each adjacent (neighboring) pair of second sidewalls <NUM> forms an array of the second cavities <NUM> therebetween. Referring to <FIG>, each of the second cavities <NUM> extends (e.g., generally radially) through the second cellular core <NUM> to and between the first skin <NUM> and the second skin <NUM>. Referring to <FIG>, each second cavity <NUM> may have a polygonal (e.g., hexagonal) cross-sectional geometry when viewed in a plane parallel to one or more of the elements <NUM> and/or <NUM> (see <FIG>). The present disclosure, however, is not limited to any particular cellular core configurations. The present disclosure is also not limited to embodiments where the second cellular core <NUM> is connected directly to the first skin <NUM> and the second skin <NUM>. For example, in other embodiments, at least one reinforcement sheet may be arranged between the second cellular core <NUM> and the first skin <NUM> and/or at least one reinforcement sheet may be arranged between the second cellular core <NUM> and the second skin <NUM>, for example, in a similar manner as described above with respect to the reinforcement sheets <NUM> and <NUM>.

The first cellular core <NUM> of <FIG> has a first core configuration with a first density. The second cellular core <NUM> of <FIG> has a second core configuration with a second density. Here, the term "density" may describe a ratio of material to open space in a cellular core. For example, a cellular core with a relatively low density may be configured with smaller cavities than a cellular core with a relatively high density. In the embodiments of <FIG> and <FIG>, the first density of the first cellular core <NUM> is different (e.g., greater) than the second density of the second cellular core <NUM>. The present disclosure, however, is not limited to such an exemplary embodiment.

Referring again to <FIG>, the first cellular core <NUM> is arranged (e.g., axially) between and may be next to, adjacent and/or abutted against the second cellular core <NUM> and the mount <NUM>. The first cellular core <NUM> is arranged (e.g., radially) between and connected to the first skin <NUM> and the second skin <NUM>. More particularly, the first cellular core <NUM> is arranged between and connected (e.g., bonded / liquid interface diffusion (LID) bonded) to the first reinforcement sheet <NUM> and the second reinforcement sheet <NUM>. The first reinforcement sheet <NUM> in turn is arranged between and connected (e.g., bonded / liquid interface diffusion (LID) bonded) to the first cellular core <NUM> and the first skin <NUM>. Similarly, the second reinforcement sheet <NUM> is arranged between and connected (e.g., bonded / liquid interface diffusion (LID) bonded) to the first cellular core <NUM> and the second skin <NUM>.

The second cellular core <NUM> is arranged (e.g., radially) between and connected (e.g., bonded / liquid interface diffusion (LID) bonded) to the first skin <NUM> and the second skin <NUM>.

Referring to <FIG>, the mount <NUM> may be configured as an arcuate body; e.g., an arcuate monolithic body. The mount <NUM> of <FIG>, for example, extends circumferentially about the centerline <NUM>. The mount <NUM> of <FIG> extends axially along the centerline <NUM> between an interior end <NUM> and an exterior end <NUM>.

The mount <NUM> of <FIG>, <FIG> includes a base <NUM> and a coupler <NUM>. The base <NUM> of <FIG>, <FIG> includes an arcuate first (e.g., inner) flange <NUM>, an arcuate second (e.g., outer) flange <NUM> and an arcuate web <NUM>. The web <NUM> extends (e.g., radially) between and is connected to the first flange <NUM> and the second flange <NUM>. The web <NUM> may be located at (e.g., on, adjacent or proximate) the exterior end <NUM> of the mount <NUM>. The first flange <NUM> projects (e.g., axially) out from a first (e.g., inner) end <NUM> of the web <NUM> in a first direction; e.g., towards the cores <NUM> and <NUM>. The second flange <NUM> projects (e.g., axially) out from a second (e.g., outer) end <NUM> of the web <NUM> in the first direction.

The first flange <NUM> of <FIG> is (e.g., axially and circumferentially, partially) overlapped by the first skin <NUM>. The first flange <NUM> is abutted (e.g., axially) against the first reinforcement sheet <NUM> and the first cellular core <NUM>. The first flange <NUM> is connected (e.g., bonded / liquid interface diffusion (LID) bonded) to the first skin <NUM> using, for example, LID bonding foil.

The second flange <NUM> is (e.g., axially and circumferentially, completely) overlapped by the second skin <NUM> as well as the second reinforcement sheet <NUM>. The second flange <NUM> is abutted (e.g., axially) against the first cellular core <NUM>. The second flange <NUM> is connected to the second skin <NUM>. More particularly, the second flange <NUM> is connected (e.g., bonded / liquid interface diffusion (LID) bonded) to the second reinforcement sheet <NUM>. The second reinforcement sheet <NUM> is in turn between and connected (e.g., bonded / liquid interface diffusion (LID) bonded) to the second flange <NUM> and the second skin <NUM> using, for example, LID bonding foil.

The coupler <NUM> is configured as an arcuate member, specifically an arcuate flange, and more specifically an arcuate V-blade (see also <FIG>). The coupler <NUM> is positioned at the exterior end <NUM> of the mount <NUM> and/or a (e.g., axial) end of the cowl door <NUM>. The coupler <NUM> projects (e.g., radially inward) from the base <NUM> and its first flange <NUM>. The coupler <NUM> also projects (e.g., radially) away from the first skin <NUM> (see also <FIG>). With this configuration and arrangement, the coupler <NUM> is operable to project (e.g., radially) into and mate with the receptacle <NUM>. The coupler <NUM> may thereby reduce or prevent (e.g., axial) movement of the cowl door <NUM> relative to the fixed structure <NUM> when the cowl door <NUM> is in its closed position.

The seal element <NUM> is mounted to the first flange <NUM> (see also <FIG>). The seal element <NUM> is configured to press (e.g., radially) against the fixed structure <NUM> so as to form a sealed interface between the fixed structure <NUM> and the cowl door <NUM>.

In some embodiments, referring to <FIG>, the cowl door <NUM> may be configured without the first reinforcement sheet <NUM> and/or the second reinforcement sheet <NUM>.

In some embodiments, the cowl door <NUM> may be configured with a single cellular core; e.g., the core <NUM> or <NUM>.

In some embodiments, the cowl door <NUM> may be configured without the seal element <NUM>.

In some embodiments, one or more or each component <NUM>, <NUM> of the cowl door <NUM> of <FIG> and <FIG> may be constructed from or otherwise include metal such as, but not limited to, pure titanium (Ti) or titanium alloy.

In some embodiments, the base <NUM> may be configured as a solid body; e.g., without a channel defined between the flanges <NUM> and <NUM> (e.g., see <FIG>).

In some embodiments, the cowl door <NUM> may be configured as an inner cowl door.

Claim 1:
An assembly (<NUM>) for an aircraft propulsion system (<NUM>), comprising:
a cowl door (<NUM>) movable between a closed position and an open position;
the cowl door (<NUM>) including a structural panel (<NUM>) and a mount (<NUM>);
the structural panel (<NUM>) including an inner skin (<NUM>), an outer skin (<NUM>) and a cellular core (<NUM>,<NUM>) connected to and arranged between the inner skin (<NUM>) and the outer skin (<NUM>); and
the mount (<NUM>) comprising a base (<NUM>) and a coupler (<NUM>), the base (<NUM>) connected to and arranged between the inner skin (<NUM>) and the outer skin (<NUM>),
wherein:
the coupler (<NUM>) projects out from the base (<NUM>) and radially inward from the base (<NUM>) away from the inner skin (<NUM>); and
the coupler (<NUM>) being positioned at an axial end of the cowl door (<NUM>),
characterized in that:
the coupler (<NUM>) comprises an arcuate V-blade; and
the cellular core (<NUM>,<NUM>) comprises a first cellular core (<NUM>), and the structural panel (<NUM>) further includes a second cellular core (<NUM>) connected to and arranged between the inner skin (<NUM>) and the outer skin (<NUM>), and the first cellular core (<NUM>) is arranged between and is abutted against the second cellular core (<NUM>) and the mount (<NUM>).