Patent Description:
Test cells are commonly used for testing aircraft engines. Specific test cell equipment is generally used, consisting of a bell-mouth, a cowling or test nacelle, a nozzle and plug, a boat-tail and an adapter. The adapter is designed to attach an upper portion of the test nacelle to an upper support in the test cell, so that the aircraft engine and test equipment assembly is properly fastened in the test cell.

Assembling the aircraft engine and the test equipment requires manipulating the aircraft engine relative to the test equipment, whereas such manipulations are complex, time-consuming and can cause damages to the aircraft engine and the test equipment if done without sufficient care. Nowadays, the aircraft engine is usually manipulated by means of a crane or a monorail, i.e. suspended means.

There is therefore a need for facilitating the assembly of the test equipment (sensors, blank-off, starter, harness, fuel pipe. ) on an aircraft engine and then the final assembly of the engine to its adapter and transport of the resulting package assembly to a test cell. The same applies to the reverse, e.g. once the tests are over, i.e. transporting the assembly out of the test cell and disassembling the aircraft engine from the test equipment.

Prior art patent document published <CIT> discloses a cart for handling an aircraft engine during assembly. The cart comprises a base frame that can be lifted and towed, and a side frame with rotating carrying means of the core of an aircraft engine. This rotating carrying means is configured for receiving the core in a vertical orientation and for pivoting said core to a horizontal orientation for assembly with another module of the aircraft engine. That cart is designed for a specific operation in the assembly of an aircraft engine, i.e. is not suitable for assembling a complete aircraft engine with a test equipment.

Prior art patent document published <CIT> discloses a cart for transporting an aircraft engine, in particular equipped with thrust reversal, the cart comprising essentially a base frame optionally equipped with wheels, and two side arms pivotally mounted on the base frame with upper ends for engaging with two upper anchoring points of the aircraft engine, located under the outer casing of the nacelle of said engine. The cart can also comprise a lower transversal support beam arranged on the base frame, with two lateral ends for engaging with two lower anchoring points of the aircraft engine. The purpose and advantage of that cart is to be compact, in particular in width, essentially for facilitating the transport of the aircraft engine. It is not suitable for assembling an aircraft engine to a test equipment and for transporting such an assembly to a test cell. Further carts are known from the prior art patent documents <CIT>, <CIT>, <CIT> and <CIT>.

Therefore, there is a need for facilitating and improving assembling an aircraft engine to a test equipment and transporting such an assembly to a test cell.

The invention is directed to a cart for transporting an aircraft engine according to claim <NUM> and to a method of transporting an aircraft engine to a test cell according to claim <NUM>. Further embodiments are defined in the appended dependent claims.

The adapter is a test equipment adapter, i.e. to secure the aircraft engine to the test cell thrust stand including the test nacelle or cowling.

The invention is particularly interesting in that it provides an efficient and practical means for assembling an aircraft engine with a test nacelle and also for transporting that assembly to a test cell, and vice versa.

Various embodiments will now be described in detail with reference to the drawings, which are provided as illustrative examples of the disclosure so as to enable those skilled in the art to practice the disclosure. Notably, the figures and the examples below are not meant to limit the scope of the present disclosure. Where certain elements of the present disclosure may be partially or fully implemented using known components (or methods or processes), only those portions of such known components (or methods or processes) that are necessary for an understanding of the present disclosure will be described, and the detailed descriptions of other portions of such known components (or methods or processes) will be omitted so as not to obscure the disclosure. Further, various embodiments encompass known equivalents to the components referred to herein by way of illustration.

<FIG> is a perspective view of a cart for transporting an aircraft engine, according to the invention.

The cart <NUM> comprises a base frame <NUM> that is advantageously generally planar though showing a certain depth, e.g. at least <NUM>, equipped with wheels <NUM> that are for instance hidden in the base frame. The wheels <NUM> are advantageously each steerable and driven in rotation, e.g. by an electric motor. The wheels <NUM> are advantageously structured and designed for allowing the cart to turn on its self, i.e. with a turning radius close or equal to <NUM>.

The cart <NUM> comprises also posts <NUM> and <NUM> extending vertically from the base frame <NUM>. The posts can comprise two front posts <NUM> and two rear posts <NUM>. Each of them is located adjacent an edge of the base frame <NUM>. The two front posts <NUM> and the two rear posts <NUM> are located on either sides of a longitudinal axis <NUM> of the cart <NUM>.

The cart <NUM> comprises also engine arms <NUM> and <NUM> structured and designed for carrying the aircraft engine <NUM>. These engine arms <NUM> and <NUM> extend horizontally and are movable vertically. They are supported by the posts <NUM> and <NUM>. The engine arms comprise for instance two front engine arms <NUM> carried each by one of the front posts <NUM>. The right front engine arm <NUM> is not visible in <FIG>. The engine arms comprise also one rear engine arm <NUM> carried by one of the rear posts <NUM>, in the present case the right rear post <NUM>. Each post <NUM> and <NUM> supporting an engine arm <NUM> or <NUM> comprises a guiding rail and mechanism for vertically moving the engine arm along the rail. That mechanism can be a thread spindle arranged vertically and engaging with a nut fastened to the corresponding engine arm. Other mechanisms, like a hydraulic cylinder (and not limited to), can be considered. The two front engine arms <NUM> are generally straight and extend perpendicularly to the longitudinal axis <NUM> of the cart <NUM> whereas the rear engine arm <NUM> comprises a first portion <NUM> directly supported by the rear post <NUM> and extending parallel to the longitudinal axis <NUM>, and a second portion <NUM> pivotally connected to the first portion <NUM>, movable between a position where it is essentially in line with the first portion <NUM> and a position where it extends transversally, for instance perpendicularly to the longitudinal axis <NUM>.

The front and/or rear engine arms <NUM> and <NUM> can comprise, each, a distal portion that is removably attached to a main portion of said arm, so as be modular. Each distal removable portion would then be adapted to a particular aircraft engine model or type with a given geometry. The attachment of the distal removable portion to the main portion of the corresponding engine arm can be by self-locking engagement, making use or not of fasteners.

The engine arms <NUM> and <NUM> can be engaged with the corresponding front and rear posts <NUM> and <NUM> in a removable manner so as to be easily replaced by others adapted to another type of engine.

The cart <NUM> comprises also adapter arms <NUM> located at higher position than the engine arms <NUM> and <NUM> and configured for engaging with an adapter of a test equipment, as this will be detailed below in connection with <FIG>. The adapter arms <NUM> comprise in the present embodiment four adapter arms <NUM>, i.e. two adapter arms <NUM> on each side of the longitudinal axis <NUM> of the cart <NUM>. The adapter arms <NUM> are designed for working in unison, i.e. do not need to be movable relative to each other. In the present embodiment, each pair of adapter arms <NUM>, on each side of the longitudinal axis <NUM> of the cart <NUM>, is rigidly fastened to a common longitudinal beam <NUM> supported by the corresponding front post <NUM> and rear post <NUM>. The longitudinal beam <NUM> is advantageously pivotally mounted on the front post <NUM> and rear post <NUM>, about a longitudinal axis. This pivoting movement is for moving the adapter arms <NUM> from an active position where they extend essentially horizontally to an inactive position where they free or widen, compared with the active position, a central area of access from above, as illustrated in <FIG>, and vice versa.

In the present embodiment, the adapter arms remain fixed in the active position, e.g. by means of appropriate arresting and/or abutting means (not visible or not represented) in the pivoting connection between the longitudinal beams <NUM> and the corresponding front and rear posts <NUM> and <NUM>. In that case, the wheels <NUM> are mounted on the base frame <NUM> such that said base frame can be selectively lifted or lowered relative to said wheels <NUM>, so as to selectively lift or lower the adapter arms <NUM>. Alternatively or complementary to such wheels, the base frame can comprise integrated jacks configured for being lowered so as to contact the ground and raise said base frame <NUM> upwardly, similarly to outriggers and stabilizers on mobile cranes.

Alternatively, the adapter arms <NUM> can be movable vertically, similarly to the engine arms <NUM> and <NUM>, in which case the base frame <NUM> does not need to be vertically movable relative to the wheels <NUM> or the ground.

As this is apparent in <FIG>, the adapter arms <NUM> comprise each a free end <NUM> with a recessed upper profile structured and designed for securely engaging with the adapter. The same applies to the engine arms whereas this is not visible in <FIG> but well in <FIG> (see <NUM>).

The base frame <NUM> advantageously comprises a generally planar floor <NUM> particularly adequate for enabling and facilitating personnel to work on and around the aircraft engine <NUM> while supported by the engine arms <NUM> and <NUM> as illustrated in <FIG>.

The cart <NUM> can comprise a control unit of the wheels <NUM> structured and designed for enabling the cart to move as a self-driven vehicle. It can also comprise guiding means along a track on the floor, e.g. optical and/or magnetic detecting means, laser scanning (but not limited to), for enabling the cart to move in an autonomous way along the track, similarly to carts carrying parts or workpieces in a production factory, from one workstation to a next one in a safe way (personnel and equipment protection).

The cart <NUM> illustrated in <FIG> will be further detailed in connection with <FIG>.

<FIG> illustrate also successive phases of a method of transporting an aircraft engine to a test cell, according to the invention.

In <FIG>, the aircraft engine <NUM> is placed on the engine arms <NUM> and <NUM> by an external means like a crane. To that end, the adapter arms <NUM> are advantageously brought in their inactive position freeing or widening, compared with the active position, a central area of access from above, as illustrated in <FIG>. More specifically, in <FIG>, the aircraft engine <NUM> is carried at its front portion by the two front engine arms <NUM> and at its rear portion by the (right) rear engine arm <NUM>. In that position, at arms' height, the engine can be comfortably further assembled and/or prepared for the test.

In <FIG>, the cart <NUM> with the aircraft engine <NUM> is moved towards a test equipment <NUM> placed on a support <NUM>. The test equipment <NUM> comprises for instance an adapter <NUM> and a test nacelle <NUM> attached at its upper portion to the adapter <NUM>. Such a test equipment <NUM> is as such known from the skilled person and does not need to be specifically further detailed. As this is apparent in <FIG>, the rear portion of the aircraft engine <NUM> is oriented towards the main opening of the test nacelle <NUM> in order to penetrate it.

Also, a central post <NUM> is placed below the rear portion of the aircraft engine <NUM> so as to carry said rear portion. The rear engine arm <NUM> is disengaged from the engine rear portion and pivoted to the inactive position where it extends completely longitudinally, i.e. where the second portion <NUM> is aligned with the first portion <NUM>.

In <FIG>, the cart <NUM> with the aircraft engine <NUM> is further moved towards the test equipment <NUM>, where the rear portion of the aircraft engine <NUM> starts to penetrate the test nacelle <NUM>. The rear engine arm <NUM> does not interfere with the test nacelle <NUM> for it is brought to the inactive position extending between the corresponding front post <NUM> and rear post <NUM>.

As this is apparent in <FIG>, the rear posts <NUM> are sufficiently laterally distant from each other so as to pass outside of the test nacelle <NUM>.

As this is also apparent in <FIG>, the adapter arms <NUM> are brought in their active position in order to pass below the adapter <NUM> when the cast <NUM> is further moved towards the test equipment <NUM>.

Important is to note that the test nacelle is essentially made of two half-shells hinged together at an upper portion adjacent to the adapter <NUM> and separated from each other at a lower portion (see <FIG>), enabling the central post <NUM> to pass freely through that free lower space.

In <FIG>, the aircraft engine <NUM> has reached its final position relative to the test nacelle <NUM>. In that position, the rear engine arm <NUM> can be brought back to its active position, i.e. by bringing the second portion thereof (not visible in <FIG>) in a transversal position extending towards the rear portion of the aircraft engine <NUM> so as to engage again with said engine. The rear engine arm <NUM>, once engaged back with the aircraft engine <NUM> can be slightly lifted so as to release the central post <NUM> which can then be removed. The aircraft engine <NUM> is then carried by the two front engine arms <NUM> and the rear engine arm <NUM>. Its position relative to the test nacelle <NUM> can be finely adjusted by adjusting the height of the engine arms <NUM> and <NUM>. Once the position of the aircraft engine <NUM> is mated with the test nacelle <NUM>, said engine is rigidly fastened to the test nacelle <NUM>.

The engine arms <NUM> and <NUM> can then be lowered so as to be disengaged from the aircraft engine <NUM> while the latter and the test nacelle <NUM> are held in position by the adapter <NUM> placed on the support <NUM>.

As this is visible in <FIG>, the test equipment <NUM> can comprise a bell-mouth <NUM> simulating the inlet of the real nacelle of the aircraft. That bell-mouth <NUM> can be mounted on the front portion of the aircraft engine <NUM> once the aircraft engine <NUM> has reached its final position relative to the test nacelle <NUM>.

In <FIG>, the adapter arms <NUM> are lifted to as to engage with the adapter <NUM> and lift said adapter from the support <NUM>. To that end and with reference to the above discussion relative to <FIG> and the wheels of the cart <NUM>, that movement can be achieved by lifting the base frame <NUM> relative to the wheels (not visible) while the adapter arms <NUM> remain in a fixed position relative to the base frame <NUM>. Still with reference with the above discussion, this can also be achieved by a relative movement of the adapter arms <NUM>. Once the adapter <NUM> is lifted from the support <NUM>, e.g. by a few millimeters or centimeters, the cart <NUM> can move away from the support <NUM> either by a reverse movement or a forward movement. The aircraft engine and test nacelle assembly <NUM>+<NUM> is then supported exclusively by the adapter arms <NUM> via the adapter <NUM>.

<FIG> shows the cart <NUM> carrying the aircraft engine and test nacelle assembly <NUM>+<NUM> after disengagement of the support <NUM> as mentioned in relation with <FIG>. The cart <NUM> can then transport the aircraft engine and test nacelle assembly <NUM>+<NUM> to a test cell.

It goes without saying that the above phases can take place in the reverse order once the test is finished.

Claim 1:
Cart (<NUM>) for transporting an aircraft engine (<NUM>), comprising:
a base frame (<NUM>) equipped with wheels (<NUM>) for riding on a floor;
at least two engine arms (<NUM>, <NUM>) extending horizontally and movable vertically relative to the base frame (<NUM>), structured and designed for supporting the aircraft engine (<NUM>); and being characterised in that it further comprises
at least two adapter arms (<NUM>) extending horizontally at a higher level than the at least two engine arms (<NUM>, <NUM>), structured and designed for supporting an adapter (<NUM>) coupled to a test nacelle (<NUM>), at the top of the aircraft engine (<NUM>).