FR2724920A1 - Swingletree for handling of heavy aircraft engines - Google Patents

Abstract

The swingletree is temporarily joined to a rolling platform by a stirrup (22) and to a load. The stirrup (22) supports a longitudinal beam (11) to each end of which is fixed, on the upper side face of the beam, a trolley (8) able to engage in a receptor suspension rail at a work post. The longitudinal beam supports at each of its ends a transverse beam, of unequal length, on the ends of which are anchored the load connectors. Adjusters ensure the desired orientation of the load relative to the vertical and horizontal. The suspension stirrup which slides along the longitudinal beam is displaced by a threaded piece meshing with an endless screw fixed parallel to the longitudinal beam.

Description

 The present invention relates to an installation of the type comprising an overhead crane and at least one work station in which a load must be conveyed and / or with respect to which a load must be positioned, installation usable in particular for moving and routing with precision and safety a heavy and costly load, such as an aircraft engine for its dressing.

 It is to this particular application that reference will be made in the present description, it being understood however that the installation can be used in the handling of other loads.

By "covering" means the positioning on the engine
- airplane fixing plates
- connections from the engine to the aircraft (for the transmission of thrust, and in particular the supply of pressurized oil, electricity, cabin air) and from the aircraft to the engine (for the supply of fuel, and in particular the supply of electrical flight control signals, compressed air for the starting circuit), and
- the rollover.

 To carry out this dressing, manufacturers use, on the one hand, a preliminary assembly station where the engine receives in particular its mounting plates to the aircraft (preliminary dressing), on the other hand, a final dressing station formed of a load-bearing structure, part of which, hereinafter called "engine mast standard", reproduces elements of the aircraft for which the engine to be dressed is intended, so as to be able to make a physical connection (assembly of the fixing plates and making the aforementioned connections) between said engine and said engine mast standard (final covering). Once the operation is complete, the dressed engine is separated from the standard of the engine mast and ready to be mounted on the real aircraft.

 There is one type of engine mast standard available per engine type.

 The preliminary assembly station and the final assembly station are provided so that the engine being trimmed is placed high to allow technicians to have access to its entire periphery.

 The difficulty encountered by professionals is to align the engine very precisely with the standard of the engine mast to bring the engine mounting plates exactly opposite those of the false plane. The operation is delicate because of the weight of the engine (around 5 tonnes) and the financial consequences of an unfortunate maneuver that would damage the engine.

 Manufacturers specializing in the dressing of aircraft engines receive the "bare" engine resting on a transport frame provided with small wheels allowing only very basic horizontal movements and no vertical movement, so that this frame cannot be used to operate the movements necessary for dressing.

So far, the technique used has been
a) removing the bare motor from the transport frame by joining together by bolting the anchoring members which said motor comprises for this purpose, at the ends of connection means dependent on a lifting machine, lifting said motor and depositing it on a "positioner" consisting of a carriage on wheels, movable horizontally, and on which rests a chassis movable vertically
b) releasing the engine from the hoist
c) to bring the positioner thus loaded with the engine to a preliminary assembly station, provided with suspension means
d) bolting said suspension means to the engine anchoring members
e) extract the positioner from the assembly station where the motor remains suspended
f) once the preliminary dressing is finished, bring the positioner back to the preliminary assembly station,
g) releasing the engine from said suspension means by unbolting them from the engine anchoring members
h) to route the positioner thus loaded with the engine to the final dressing station and to bring the engine mounting plates exactly opposite those of the counterfeit aircraft,
i) fix the engine to the standard of the engine mast and move the positioner away
j) once the final trim is complete, dismantle the cowling to free access to the engine anchoring members, otherwise the engine would no longer be maneuverable
k) to bring the positioner under the standard of the engine mast
1) to release the dressed engine from the standard of the engine mast by separating their fixing plates and receiving it on the positioner
m) routing the positioner thus loaded from the dressed engine to the transport chassis; and
n) pass the dressed engine over the transport chassis using a lifting device gripping the dressed engine by its anchoring members.

 To implement step h), the positioner must not only allow movement along three orthogonal axes (horizontal X and Y, and vertical Z), but also be able to allow rotation around the X axis and rotation around the Y axis to take into account the fact that the center of gravity of an engine is not located at the intersection of its vertical and horizontal median planes.

 We understand that, to bring the engine mounting plates exactly opposite those of the false plane, using a cart rolling on the ground, we must engage in multiple approaches that take about three and a half hours, the operation involving, by engine, four people, each of whom monitors the maneuver at an approach point and one of whom, in addition, controls the maneuver. In addition, the operation requires that each final dressing station be at least 30 meters wide to allow the positioner maneuvers. Provision could be made for the positioner to be able to move "crabwise", but it is practically impossible to obtain such movement with the required precision.

The object of the present invention is to remedy these drawbacks by proposing means which eliminate any recourse to a machine rolling on the ground in the context of the engine covering.
More specifically, the invention proposes a spreader comprising, on the one hand, means of temporary assembly at an overhead crane and on the other hand, means of temporary assembly at a load (in the example taken, an engine to be dressed) , characterized in that said means of temporary assembly to the traveling crane consist of a stirrup supporting a longitudinal beam at each end of which is fixed, on the upper face side of the longitudinal beam, a carriage adapted to engage with a rail of receiver suspense belonging to a work station (in the example taken, a preliminary dressing station).

 Thanks to these provisions, once its connection means bolted to the engine anchoring members, the lifter according to the invention accompanies said engine from its arrival, naked on the transport chassis, until the moment when it is fixed on the fake plane.

Indeed, with the lifter according to the invention, the technique used to move and position the engine to be dressed consists
a) bringing the transport chassis carrying the bare engine perpendicular to the overhead crane to which the lifter is suspended and bringing said lifter upright and in close vertical proximity to the engine
b) bolting the lifter connection means to the engine anchoring members and removing said engine from the transport frame by actuating the traveling crane
b) bringing the carriages of the longitudinal beam of the lifter opposite the rail of the preliminary assembly station, and then engaged with the latter
c) to separate the lifter from the crane
d) once the preliminary dressing is completed, join the lifting beam to the overhead crane and extract the carriages from the longitudinal beam of the rail of the preliminary dressing station
e) actuating the overhead crane so as to bring the engine mounting plates exactly opposite that of the standard of the engine mast of the final dressing station, and to bring them together,
g) to separate the spreader from the motor
h) once the final covering is finished, dismantle the cowling to free access to the engine anchoring members and bolt the lifter connection means to said anchoring members
i) to separate the engine from the false aircraft, and
j) by actuating the overhead crane, bring the dressed engine back to and on the transport chassis.

 All the movements of the lifter are ensured by the traveling crane, it being understood that once its carriages are engaged with a receiving rail, the lifter can even be moved by hand. It is understood that the maneuvers using a traveling crane, in the three directions, are infinitely easier and more flexible than a maneuver using a rolling machine on the ground. We also see that the number of operations to be performed is reduced. This results in a saving of working time of the order of 3 hours per technician (i.e. 3 hours x 4).

 In addition, it is no longer necessary to give 30 meters in width to the final dressing station: 20 meters is sufficient. We can therefore reduce the size of the premises or install more stations, with equal surface area. The economy of surface results in savings in heating, lighting, etc ...

 The longitudinal beam of the lifting beam according to the invention comprises, at each of its ends, a transverse beam on the ends of each of which are anchored the means of connection to the load (to the motor).

 To take into account the fact that the diameter of an aircraft engine is wider on the air intake side than on the gas outlet side, the cross bars of the lifter are of unequal length.

 As indicated above, the center of gravity of an engine is not located at the intersection of its horizontal and vertical median planes. In addition, the position of the center of gravity varies depending on the stage of the dressing and / or equipment or instrumentation with which it is provided.

 To take this into account, the lifter according to the invention comprises adjustment means adapted to ensure a desired orientation of the load (of the motor) relative to the vertical and the horizontal.

 To ensure adjustment around a horizontal axis perpendicular to the longitudinal beam of the lifter, the hanger suspension hanger is slidably mounted along said longitudinal beam. More specifically, the stirrup is subjected to the displacement of a threaded piece engaged with an endless screw itself secured to the longitudinal beam and parallel to said beam.

 To ensure adjustment around a horizontal axis parallel to the longitudinal beam of the lifter, the suspension bracket is pivotally mounted about an axis parallel to said longitudinal beam, the pivoting being obtained by providing, in the bracket, reception spaces adapted to receive an appropriate ballast on one side or the other of said longitudinal beam. In practice, the axis around which the pivoting is effected under the effect of the ballast and the worm screw are one and the same piece, the stirrup being integral with a free tab rotating in rotation around the worm screw but subject in translation when moving the threaded part engaged with said worm.

 To allow easy access to the final dressing station of the engine having undergone the preliminary dressing, that is to say of the engine provided inter alia with its fixing plates to the engine, said final dressing station consists of a bracket fixed, generally taking the form of a capital gamma r having a vertical branch and a roughly horizontal branch, the latter, called "cantilevered arrow", supporting the false airplane.

 The arrow tapers from its distal end to its proximal end, relative to the vertical branch of the bracket. We understand that this tapered configuration is intended to allow the lifter, responsible for the engine to finish dressing, to come "slip" on this arrow by engaging it by its narrowest side (that is to say, shortest crossbar side).

 More specifically, the arrow is made up of a proximal part and a distal part, this, relative to the vertical branch of the bracket, each of said proximal and distal parts being made up of a network of beams each forming a set in oblique pyramid trunk with four faces and vertical bases, the large bases of the two pyramid trunks being located on the proximal side and the pyramid trunk of the proximal part being inclined upwards, while that of the faces which is turned towards the ground of the pyramidal trunk of the distal part, is horizontal, said face supporting the false plane.

The invention extends its scope not only to the spreader and to the final covering station of the aircraft engine defined above, but also to any installation for conveying and / or positioning a load towards, or with respect to, at least one work station, said installation comprising an overhead crane and a lifting beam comprising means of temporary assembly to said load, characterized in that
said spreader is as defined above, and
- Said work station comprises a receiver suspension rail adapted to engage with the carriages of said lifter.

The invention also extends its scope to an installation for covering an aircraft engine, said installation comprising at least one preliminary dressing station where the engine in particular receives its mounting plates for the aircraft for which it is intended. and a final dressing station comprising a structure reproducing elements of the aircraft for which the engine to be dressed is intended, known as a "false airplane", said installation being characterized in that it comprises
- an overhead crane
at least one spreader comprising, on the one hand, temporary meeting means to said traveling crane and, on the other hand, temporary meeting means to said aircraft engine and
- at least one final dressing station as defined above.

The invention also relates to an installation for the covering of an aircraft engine, said installation comprising at least one preliminary dressing station where the engine in particular receives its mounting plates for the airplane for which it is intended and a station final trim comprising a structure reproducing elements of the aircraft for which the engine to be dressed is intended, known as a "false aircraft", said installation being characterized in that it comprises
- an overhead crane
- at least one lifting beam as defined above
at least one preliminary dressing station comprising a receiving suspension rail adapted to engage with the carriages of said lifting beam, and
- at least one final dressing station as defined above.

Other characteristics and advantages of the invention will emerge on reading the description below made with reference to the accompanying drawings in which
- Figure 1 is a schematic side elevational view showing a preliminary engine covering station, one engine being in place for the covering and another being in the process of being set up, both engines being each suspended by a lifting beam according to the invention
- Figure 2 is a top view corresponding to Figure 1, the engine located on the right in the figure, however, occupying a more engaged position inside the mounting station than in Figure 1
- Figure 3 is a schematic elevational view of an engine suspended in the mounting station of Figures 1 and 2, observed on the air intake side
- Figure 4 is a schematic elevational view of an engine suspended in the assembly station of Figures 1 and 2, observed on the gas outlet side
- Figure 5 is a side elevational view of the essential components of the lifter according to the invention
- Figure 6 is an enlargement of the right part of Figure 5
- Figure 7 is a section taken along line VII
VII of figure 5 or 6
- Figure 8 is a section taken along line VIII
VIII of figure 5 or 6
FIG. 9 is a perspective view showing the approach of the engine to the final dressing station, and
- Figure 10 is a perspective view mounting the engine attached to the false aircraft.

 If we refer to Figures 1 and 2, we see a preliminary dressing station consisting of a structure formed of vertical beams 1 and longitudinal longitudinal beams 2, transverse 3 and diagonal 4, the latter forming stiffeners. This structure supports a lifter rail 5 and two hoist rails 6a and 6b.

 Two lifting beams 7a and 7b are suspended from the rail 5 by engaging the carriages 8 which they comprise with said rail. Each of the lifting beams 7a and 7b hangs a bare motor 9a, 9b.

 In FIG. 1, the spreader 7a and the motor 9a which depends on it are deeply engaged in the preliminary dressing station while the spreader 7b and the motor 9b which depends on them are very little engaged, being in the process of positioning in the preliminary dressing station. In FIG. 2, the positioning of the motor 9b is finished and the preliminary dressing can be undertaken. It will be noted that a pneumatic stop 10, subject to adequate security, equips the free end of the rail 5 to prevent a carriage 8 from accidentally coming out of said rail.

 Each spreader 7a, 7b comprises a longitudinal beam 11 and a pair of transverse beams 12a, 12b.

 As seen in Figure 3, the transverse beam 12a supports slings 13 each joined to the upper end of a curved piece 14, called "banana", whose lower end can be bolted to an anchoring member 15 provided for this purpose on the engine 9 on the air intake side 16.

 On the other hand, as seen in FIG. 4, the transverse beam 12b supports slings 17 each bolted directly to an anchoring member 18 provided for this purpose on the engine 9 on the gas outlet side 19.

 The transverse beam 12a is longer than the transverse beam 12b to take account of the fact that the diameter of the engine is larger on the air intake side than on the gas outlet side.

 Found in Figures 3 and 4, the hoist rails 6a, 6b. These rails support electric hoists 20 used to hoist the engine hoods, namely: at the front, the air intake (weight 300 kg, diameter 3.20 m) and at the rear, the nozzle (weight 200 kg, diameter 2 m).

 The structure of the lifter 7 appears in more detail in FIGS. 5 to 8. We find there the longitudinal beam 11 (FIGS. 5 to 8) and the transverse beams 12 (FIG. 8 - only one visible), the carriages 8 (FIGS. 5, 6 and 8), and the fastening parts 21a and 21b respectively of the slings 17 and 13 (Figures 5, 6 and 8).

 As can be seen in FIGS. 5 to 7, the lifter comprises a stirrup 22 made up of two vertical flanges 23a, 23b and a bottom wall 24. The flanges 23a and 23b have three pairs of holes opposite two to two 25, 26a and 26b. The pair of holes 25 is used for the passage of suspension means to an overhead crane. The pairs of holes 26a and 26b are used for the passage of a pair of bars 27 maintaining the relative position of the stirrup 22 with respect to the longitudinal beam 11.

 The stirrup 22 also comprises (FIG. 7) a pair of guide walls 28a and 28b which delimit receiving spaces 29a and 29b between themselves and a reinforcement welded to the longitudinal beam 11, reinforcement formed by two longitudinal bars 30 and a sole 31. A ballast mass 32 which serves to compensate for a lateral angular offset from the center of gravity is slid into the receiving space 29.

 As is further apparent from FIGS. 6 and 7, the lower wall 24 of the stirrup 22 is integral with a lug 33 having an oblong hole 34. This hole receives an endless screw 35 engaged with two nuts 36a, 36b located on either side of the tab 33. The pair of nuts 36a, 36b imposes on the tab 33 a translational movement when it itself moves along the threaded rod 35, but leaves it free to rotate. It is understood that the installation of the ballast 32 in the stirrup 22 rotates the lifter about the axis formed by the worm 35 and that the movement of the pair of nuts on said worm makes the lifter pivot around an axis perpendicular to that of the worm. In FIG. 6, the two extreme positions 22 ′ and 22 "of the stirrup 22 are seen in dotted lines.

 If we come to the carriages 8, their structure is shown in Figures 6 and 8. They are formed of two vertical triangular isosceles flanges, tip down, 37. These flanges which are parallel to the longitudinal beam 11 have, on each side , transverse returns 38. They also each have two pairs of holes 39 adapted to receive bars which serve as security by keeping, on the one hand, the carriage in the high position which allows engagement in the rail without manual intervention. , and, on the other hand, the flanges 37 aligned and oriented upwards. The flanges 37 and their returns 38 form a cage receiving eight rollers (four pairs) 40 mounted on axes 43 and 44, rollers which, as shown in FIG. 8, are adapted to roll on the inner face of the "foot "45 of the I-rail 5. In addition, the flanges 37 each have a hole in their lower angle providing a passage for a semi-axis 46 depending on a part 47 welded to the longitudinal beam 11. Each flange 37 is trapped by screwing a nut 48 on the half-axis 46. It follows that the longitudinal beam 11 can pivot slightly around the half-axes 48 thus allowing the rollers 40 to align despite possible defects in the rail base 45 .

 If we come to Figure 9, we see that the final dressing station consists of a supporting structure 49 in the form of r whose vertical branch consists of a series of vertical beams 50 deeply anchored in foundations and supporting a fixed cantilevered boom 51.

The arrow 51 consists of a part 51a, called "proximal", and a part 51b, called "distal", this, relative to the vertical beams 50. The proximal part 51a consists of a network of beams forming a set of oblique pyramid trunk with four faces and vertical bases, the large base being located on the proximal side and said pyramid being inclined upwards. The distal part 51b also consists of a network of beams forming an oblique pyramid trunk assembly with four faces and vertical bases, the large base being situated on the proximal side and that 52 of the faces of the pyramid which is turned towards the ground, is horizontal.

 This face 52 is joined to the structure called "false plane" 53 adapted to receive the engine, the covering of which is to be finished. It can be seen that the part 51b of the cantilever carrying structure further supports a gateway 54 facilitating the intervention of the technicians.

The installation taken as a whole is used as follows
a) the transport chassis carrying the bare motor 9a is brought into line with the overhead crane to which the lifter 7a is suspended by its stirrup 22, then by actuating the overhead crane the said spreader 7a is plumb and near vertical immediate motor 9a
b) the free end of the bananas 14 and the free ends of the slings 17 are respectively bolted to the anchoring members 15 and 18 of the motor, and said motor is removed from the transport frame by actuating the traveling crane
c) the carriages 8 of the longitudinal beam 11 of the lifter 7a are brought opposite the rail 5 of the preliminary assembly station, and then engaged with the latter
d) to separate the stirrup 22 of the lifter 7a from the traveling crane then, by proceeding in the same way and using a second lifter 7b, it is possible to position a second motor 9b in the preliminary dressing station (then a third, etc. .)
e) once the preliminary dressing has been completed, the stirrup 22 of the lifter came last engaged with the rail 5 (here the lifter 7b) at the traveling crane and the carriages 8 are extracted from the longitudinal beam 11 of said rail 5 (we will have previously adjusted the position of the stirrup 22 longitudinally and transversely relative to the longitudinal beam 11 by advancing or retreating the pair of nuts 36a, 36b on the worm screw 35 and by loading more or less ballast 32 and on one side or the other of the longitudinal beam 11 (the adjustments to be made are provided as a function of the preliminary dressing carried out and they must result in the motor occupying a position such that its horizontal and vertical median planes in the suspended state correspond well to what must be its horizontal and vertical median planes of attachment to the aircraft)
f) the beam 22 of the lifter 7b is then brought into the vertical plane of the standard of the engine mast 53 of the final covering station, then the fixing plates of the engine 9b opposite that of said standard of the engine mast 53 and we put them together,
g) the spreader 7b is separated from the motor 9b
h) once the final covering is finished, the cowling is dismantled and the bananas 14 and the slings 17 are bolted to anchoring members provided on the engine
i) the dressed engine 9b is separated from the standard of the engine mast 53, and
j) by actuating the crane, the motor is brought back to, and on, the transport chassis.

 It appears from the foregoing description that the installation according to the invention, and in particular the specially designed lifting beam, considerably facilitates operations, increases safety and productivity.

Claims (14)

 1 - spreader comprising, on the one hand, means of temporary meeting at an overhead crane and on the other hand, means of temporary meeting at a load (9; 9a; 9b), characterized in that said means of temporary meeting to the traveling crane consist of a stirrup (22) supporting a longitudinal beam (11) at each end of which is fixed, on the upper face side of the longitudinal beam (11), a carriage (8) adapted to engage with a receiver suspension rail (5) belonging to a work station.  2 - spreader according to claim 1, characterized in its longitudinal beam (11) supports, at each of its ends, a transverse beam (12a, 12b) on the ends of each of which are anchored the means of connection to the load.  3 - spreader according to claim 2, characterized in that its transverse bars (12a, 12b) are of unequal length.  4 - spreader according to any one of claims 1 to 3, characterized in that it comprises adjustment means (32, 33, 35, 36) adapted to ensure a desired orientation of the load (9; 9a; 9b) with respect to the vertical and the horizontal.  5 - spreader according to claim 4, characterized in that said suspension bracket (22) is slidably mounted along said longitudinal beam (11).  6 - spreader according to claim 5, characterized in that the stirrup (22) is subjected to the displacement of a threaded piece (36a, 36b) engaged with an endless screw (35) itself secured to the longitudinal beam (11 ) and parallel to said beam.  7 - A lifting beam according to any one of claims 4 to 6, characterized in that the suspension bracket (22) is pivotally mounted about an axis parallel to said longitudinal beam (11).  8 - spreader according to claim 7, characterized in that said stirrup (22) comprises receiving spaces (29a, 29b) adapted to receive a ballast (32) suitable on one side or the other of said longitudinal beam ( 11).  9 - spreader according to any one of claims 4 to 8, characterized in that the stirrup (22) is integral with a leg free in rotation but subjected in translation to the movement of the threaded part (36a, 36b) in engagement with the worm screw (35).  10 - Installation for conveying and / or positioning a load (9; 9a; 9b) towards, or with respect to, at least one work station, said installation comprising an overhead crane and a lifting beam comprising means of temporary meeting with said load (9; 9a; 9b), characterized in that:  said spreader is according to any one of claims 1 to 9, and  - Said work station comprises a receiving suspension rail (5) adapted to engage with the carriages (8) of said lifter.  11 - Installation according to claim 10, the work station of which is intended for the final covering of an aircraft engine equipped with plates for its attachment to the aircraft for which it is intended, characterized in that said station final covering consists of a fixed bracket (49), generally taking the form of a capital gamma r having a vertical branch (50) and a roughly horizontal branch (51), the latter, known as "cantilever arrow" , supporting a structure (53) reproducing elements of the airplane for which the engine to be dressed is called, "engine mast standard".  12 - Installation according to claim 11, characterized in that said arrow (51) of said final dressing station tapers from its distal end to its proximal end, relative to the vertical branch of the bracket.  13 - Installation according to claim 11 or 12, characterized in that said arrow (51) of said final dressing station consists of a part (sua) proximal and a part (51b) distal, each of said proximal parts and distal consisting of a network of beams forming a set of oblique pyramid trunk with four faces and vertical bases, the large bases of the two pyramid trunks being located on the proximal side and the pyramid trunk of the proximal part (51a) being inclined upwards, while that (52) of the faces which faces the ground of the pyramid trunk of the distal part (51b), is horizontal, said face (52) supporting the standard of the engine mast (53).  14 - Installation according to any one of claims 11 to 13, characterized in that it further comprises  - at least one preliminary dressing station where in particular the engine (9; 9a; 9b) receives its mounting plates for the aircraft for which it is intended, and  - An overhead crane to which said lifting beam (7; 7a; 7b) may be temporarily joined together, in particular for its movement between said preliminary dressing station and said final dressing station (49).