FR3113490A1 - INSTALLATION AND METHOD FOR MANUFACTURING BRAKE DISCS - Google Patents

Abstract

The invention relates to an installation (1) for the manufacture of brake discs for an aircraft, formed from a composite material comprising a matrix and a fibrous reinforcement, the installation (1) comprising : - a first station (3) for converting parts (2) having a first inlet (30) arranged on a first level (Z0) of the installation (1); - a second station (4) for transforming the parts (2) having a second entrance (40) arranged on a second level (Z1) of the installation (1), the second level (Z1) being raised with respect to the first level (Z0); and - a tower (5) for storing and transferring parts (2) able to move between the first station (3) and the second station (4), the tower (5) comprising: - a support structure (51 ) and - at least one swing (52) capable of moving in the support structure (51) to receive the parts (2) from the first station (3) from the first level (Z0) and transfer them to the second station ( 4) by the second level (Z1). Abstract Figure: Figure 1

Description

INSTALLATION AND METHOD FOR MANUFACTURING BRAKE DISCS

Technical field of the invention

The invention relates to the field of brake discs made of composite material for aircraft, in particular for aircraft landing gear.

In particular, the invention relates to the field of brake discs made of carbon-carbon composite material.

State of the art

A carbon-carbon composite material, also called C-C composite, is made up of a fibrous reinforcement consisting of carbon fibers and a carbon-based matrix. Such a composite material has good mechanical strength, in particular at high temperature, high thermal conductivity, a high coefficient of friction at high energy and a low density compared for example to steel. Given these properties, carbon-carbon composites find numerous applications in the aerospace field, in particular for the manufacture of brake discs for aircraft.

Brake discs for aircraft in C-C composites are manufactured according to manufacturing ranges involving different operations using different types of installation specific to the specific processes implemented. The installations are generally positioned in the same manufacturing workshop in order to guarantee the continuity of the flow of parts at the different stages of their manufacture. Some operations are implemented as a unit: a single part is processed during this operation in an installation capable of processing the parts one by one. Other operations are implemented in batches of a large number of parts.

The first step is to manufacture the fibrous reinforcement. This manufacturing step consists of textile operations intended to produce a part in the form of an annular carbon fiber preform, using as raw material cables made up of a large number of filaments. The thick annular preform is for example made up of a stack of textile layers bonded together by needling, layer after layer. The chemical nature of these webs can be organic, for example if the webs consist of tows of polyacrylonitrile or carbon fibers. In the case of polyacrylonitrile fibers, obtaining a carbon fiber preform requires the implementation of a carbonization operation during which the fiber of the preforms is transformed into carbon fiber. This operation is carried out by processing a batch of preforms in a dedicated thermal chamber.

The annular preforms – often referred to by the term dry preforms – then undergo a densification step during which the porosities between the fibers are filled with the carbon matrix to form blanks. In the case of densification by gas (Chemical Vapor Infiltration), the preforms are grouped together in piles on trays which are transported and placed in the thermal chamber in which they undergo a densification treatment by gas to form blanks. . This is carried out at temperatures of the order of 1000°C and at low pressure, and under sweeping of a gas such as a hydrocarbon. These temperature and pressure conditions lead to the cracking of the gas and allow the filling of the porosities, thus constituting the carbon matrix of the composite material. Brake disc blanks are thus formed in batches of a large number of units.

Densification can be carried out in several infiltration cycles between which the blanks are peeled during a unit machining operation in order to open the surface porosities again and allow good densification during the following densification cycle.

Between densification cycles and when the blank is at the required final density, a heat treatment can also be carried out on a batch of blanks in a dedicated thermal chamber.

Finally, final machining of the blanks, including dressing of the friction faces and machining of tenons, is carried out within a machining cell to form the brake discs according to their final shape.

Thus, the manufacture of brake discs involves several transformation stations. The first transformation station brings together the textile operations of making dry preforms, peeling, and machining, and therefore performs operations on unitary elements. Conversely, the second transformation station, which notably includes large thermal chambers for carrying out the carbonization, densification and heat treatment stages, performs operations on batches of parts at the semi-finished stage grouped together in piles on plates.

Also, the first transformer station is arranged on a first level of the installation, a low level. Conversely, the loading and unloading of the trays in the thermal enclosures is done through an entrance arranged in the upper part of the thermal enclosures, which are generally a few meters high. This entry is made through an opening system at the top of the thermal enclosures such as a pivoting lid. Consequently, the second transformer station comprising in particular the thermal enclosures is arranged on a second level of the installation.

Thus, during manufacturing, the parts must be routed between manufacturing stations comprising entrances arranged on separate levels of the installation. Such a configuration of the installation requires dedicated means such as goods lifts, and generally leads to load breaks between the two levels. In addition, the processing of parts individually for certain operations, and in batches for other operations, also leads to breaks in load between the two areas. The flow of parts at the semi-finished stage between the different stations is not homogeneous, causing bottlenecks that generate cycle times and intermediate manufacturing stocks, leading to significant additional production costs.

There is thus a need to provide an installation and a manufacturing method allowing mass production of brake discs minimizing these breaks in load in order to reduce production costs.

Disclosure of Invention

To this end, the invention proposes an installation for the manufacture of brake discs for an aircraft, formed from a composite material comprising a matrix and a fibrous reinforcement, the installation comprising:

- a first part transformation station having a first entrance arranged on a first level of the installation;

- a second parts transformation station having a second entrance arranged on a second level of the installation, the second level being raised with respect to the first level; And

- a tower for storing and transferring parts capable of moving between the first station and the second station, the tower comprising:

- a support structure and

- At least one swing able to move in the support structure to receive the parts of the first station from the first level and transfer them to the second station by the second level.

According to the invention, the installation for the manufacture of brake discs therefore comprises a tower for storing and transferring parts between the various transformation stations, which makes it possible to easily transport these parts from one station to another. Furthermore, the storage tower comprises according to the invention at least one swing to accommodate the parts. Furthermore, the balancelle according to the invention moves in the support structure of the tower in order to receive the parts by one or the other level. Thus, in the first transformer station on the first level, the tower is loaded and then moved to the second transformer station placed on the second level. The swing is then moved in height according to for example a rotation-translation movement in order to align it with the second level where the parts are unloaded in order to be transferred to the second transformation station. Conversely, the parts leaving the second transformation station can be recovered at the level of the second level to be loaded onto the swing of the storage tower then transported by this mobile tower to the first manufacturing station where they are unloaded at the level of the first level, with a view to machining the parts. Thus, the storage tower makes it possible to distribute the flow of parts between the various stations, which limits load breaks and improves manufacturing speed.

According to an advantageous mode of the invention, the tower comprises a plurality of swings. The number of swings in a tower can be chosen so as to allow simultaneous storage of a full load and a full unloading of a thermal chamber. Thus, a load of parts from the first station is loaded onto the tower, which is routed opposite the second station. The parts treated in the second station are first unloaded on the available swings of the tower, then the untreated parts brought by the tower are immediately loaded into the second station. This minimizes the waiting time for the second station between two processing cycles.

The installation according to the invention may comprise one or more of the following characteristics, taken separately from each other or in combination with each other:

• the storage and transfer tower comprises an interface arranged on the support structure and capable of cooperating with a guided autonomous vehicle to move the tower;
• an electric control device capable of controlling the movement of the storage tower and the movement of the swing;
• the storage and transfer tower includes wheels on which the support structure is mounted;
• the storage and transfer tower comprises a first parts passage giving access to the first level and a second parts passage giving access to the second level;
• the distance separating the first passage and the second passage is between 2 m and 20 m, preferably between 5 m and 10 m;
• the storage and transfer tower comprises a plurality of rows of swings superimposed and distributed over two columns, each of the swings being able to be placed in the support structure;
• the support structure has a width comprised between 2 m and 20 m, preferably comprised between 5 m and 10 m and a depth less than the width of the support structure, for example comprised between comprised between 2 m and 8 m.

The invention also relates to a method for manufacturing brake discs for an aircraft comprising the following steps:

- (a) supply parts made of composite material comprising a matrix and a fibrous reinforcement, within a first transformation station having a first entrance arranged on a first level,

- (b) loading the parts from the first level into a storage and transfer tower comprising a support structure and at least one movable swing in the support structure,

- (c) move the storage and transfer tower to a second transformer station having a second entrance arranged on a second level of the installation raised above the first level,

- (d) move the swing so as to reach the second level,

- (e) transfer the parts to the second transformation station from the second level,

- (f) convert parts to supply brake discs.

Advantageously, according to the method, the swing is rotatable in the support structure.

Brief description of figures

Other characteristics and advantages will emerge from the following description of a non-limiting embodiment of the invention, with reference to the appended drawings in which:

Figure 1 is a schematic view of an installation for manufacturing brake discs for an aircraft;

Figure 2 is a schematic perspective view of an element of the installation,

Figure 3 is a longitudinal sectional view of another element of the installation,

Figure 4 is a perspective view of an example of a storage tower according to the invention,

Figure 5 is a schematic view of a method according to the invention.

Detailed description of the invention

The brake discs are intended to be mounted in the braked wheels which equip an aircraft landing gear. Brake discs are made of a fibrous reinforcement and a matrix. The fibrous reinforcement is in particular densified by the matrix. The matrix is for example a carbon matrix and the fibrous reinforcement comprises for example carbon fibers. The composite material is commonly referred to in the field of the invention as carbon-carbon (C-C) composite.

An installation 1 for manufacturing brake discs according to the invention is shown by way of example in FIG. 1. Installation 1 comprises a first station 3 for converting parts 2 having a first inlet 30 arranged on a first level Z0 of the installation 1. The parts 2 are semi-finished brake discs and thus represent, according to the present invention, the partially developed brake discs.

The first processing station 3 generally comprises a textile cell 31, carrying out textile operations to form parts 2 in the form of fiber preforms, a peeling cell 32 intended to form parts 2 in the form of blanks and a cell for machining 33 intended to form the brake discs in their final shape.

The installation 1 further comprises a second station 4 for transforming the parts 2. The second station 4 has a second entrance 40 arranged on a second level Z1 of the installation 1. The second station 4 generally comprises one or more enclosures 41 capable of at least one carbonization operation, or at least one densification operation, or at least one heat treatment operation. Preferably, opposite each enclosure 41 at level Z1 is an entrance 40. As shown in FIG. 1, the second level Z1 is raised with respect to the first level Z0. The distance D, measured along the Z axis, separating the first and the second level Z0, Z1 is of the order of a few meters, for example between 2 m and 20 m.

The installation 1 further comprises a tower 5 for storing and transferring the parts 2 capable of moving between the first station 3 and the second station 4 for processing. Depending on the configurations, the installation 1 can comprise a plurality of storage and transfer towers 5. Advantageously, the storage and transfer tower 5 has a height measured along the Z axis, equal to the distance D.

The parts 2 are manufactured individually within the textile cell 31 in the form of annular preforms.

The manufacture of the annular preforms within the textile cell 31 comprises textile operations intended to produce an annular carbon fiber preform, using as raw material cables formed of a large number of filaments. The thick annular preform is formed from a stack of textile layers bonded together, for example by needling, layer after layer. The chemical nature of these plies can be organic, for example if the plies are formed from tows of polyacrylonitrile fibers or from carbon in the case of tows of carbon fibers. Then, the parts 2 are grouped by lot 20 shown by way of example in Figure 2. A plurality of lots 20 are generally formed.

The batch 20 of coins 2 thus comprises a plurality of stacks 21 of coins 2 grouped together on a plate 22. Advantageously, the plate 22 is circular and has a diameter comprised for example between 1 m and 5 m, for example 3 m. The plate 22 comprises a plurality of orifices allowing the passage of gases and a standardization of the temperature in the parts 2 within the enclosure 41.

Preferably, the parts 2 comprise an identification member making it possible to position the parts 2 in the installation 1. The identification member is for example an RFID chip, an engraving or a machining of the parts 2. The member identification is integrated directly on the parts 2 or on the tray 22.

Batches 20 are then stored in tower 5 shown by way of example in Figure 4.

Tower 5 includes a support structure 51 and at least one swing 52.

The support structure 51 is preferably made of steel. The support structure 51 is preferably a mechanically welded structure. The support structure 51 has for example a rectangular base and extends vertically along the Z axis. The support structure 51 has for example a width L, measured along the Y axis and perpendicular to the Z axis, comprised between 2 m and 20 m, preferably between 5 m and 10 m, for example 8 m. The depth P of the support structure 51, measured along the X axis, is for example less than its width L. The depth P is for example between 2 m and 8 m, for example 4 m. These preferred dimensions make it possible to reduce the footprint of tower 5 on the ground.

Furthermore, the support structure 51 comprises a first passage 50a and a second passage 50b of the parts 2 and in particular, the batches 20. The first passage 50a gives access to the first level Z0 of the installation 1 and the second passage 50b gives access to the second level Z1 of the installation 1. Advantageously, the distance H separating the first passage 50a and the second passage 50b is equal to the distance D. It is for example between 2 m and 20 m, preferably between 5 m and 10m. The distance H is for example 7 m. Thus, according to the invention, tower 5 is capable of receiving and transferring 2 coins, in the form of 20 batches, both from the first level Z0 and from the second level Z1.

Furthermore, the support structure 51 defines an internal space 53 in which the swing 52 is arranged.

Advantageously, the tower 5 comprises a plurality of swings 52. Preferably, the tower 5 comprises swings 52 in an amount twice the number of trays 22 loaded in the enclosure 41. As shown for example in Figure 4, rows of swings 52 are superimposed and distributed mainly over two columns and arranged in the internal space 53. Preferably, the first and last row respectively located at the level of the first and second passage 50a, 50b only comprises a swing 52 centered in the internal space 53 This configuration facilitates the entry and/or exit of rooms 2.

Furthermore, the swings 52 are formed of a steel frame comprising two side walls 54 mounted on two slides 55 transverse to the side walls 54 and secured to the support structure 51. The swings 52 further comprise a bottom 56 d tray support 22.

The swings 52 according to the invention are able to move in the support structure 51. For example, the swings 52 are mounted to move in rotation and possibly in translation in the support structure 51. The system making it possible to drive the swings 52 comprises for example an electrical control device and a means for driving all of the swings 52 such as a belt or a chain. This thus allows the swings to move in the support structure to distribute the flow of parts 2. Indeed, when the tower 5 is present at the level of the first station 3 of transformation, a first batch 20 is loaded on a first swing 52 via the first passage 50a located at the first level Z0. Then, the swings are moved by a rotational movement indicated by way of example by the arrow in FIG. 4. Another swing 52 thus moves in rotation to be placed at the level of the first passage 50a replacing the swing 52 loaded with a Swing 52 not loaded. An additional batch 20 can thus be arranged in tower 5 and so on until the number of swings 52 corresponding to the complete loading of the densification enclosure 41 is loaded into tower 5.

The tower 5 advantageously comprises an interface (not shown) arranged on the support structure and capable of cooperating with an autonomous guided vehicle (AGV, for Automatic Guided Vehicle in English). Thus, the tower 5 can be moved by the vehicle between each transformer station 3, 4.

The tower 5 also comprises wheels (not shown), preferably articulated. The support structure 51 is mounted on wheels, preferably four wheels mounted on the rectangular base of the support structure 51. The wheels facilitate the movement of the tower 5 between the first station 3 and the second station 4 of transformation. Tower 5 can, according to the invention, move in translation in installation 1 at level Z0 in the plane defined by the X and Y axes. The articulated wheels facilitate such movement.

Preferably, the installation 1 comprises the electrical control device (not shown) making it possible to control the movement of the swings 52 and advantageously of the tower 5.

Thus, the tower 5 is moved from the first station 3 to the second station 4 of transformation over a distance for example of 200 m, so as to position itself for example opposite the enclosure 41 of densification to be unloaded then reloaded .

The heat-treated parts 2 are unloaded from the densification chamber 41 and transferred through the second passage 50b to tower 5 at level Z1. In the same way as before, the first empty swing 52 located at the level of the second passage 50b is loaded with a heat-treated batch 20, then the system of swings 52 is rotated in the support structure 51 to position the empty swing 52 following at the level of the second passage 50b. An additional batch 20 is thus loaded into tower 5, then another, until the densification enclosure 41 is completely unloaded.

The batches 20 loaded with non-heat-treated parts 2 are then unloaded from their swing 52 towards the densification enclosure 41 at the level of the passage 50b, until the enclosure 41 is completely loaded.

To facilitate the transfer of the parts 2 at the semi-finished stage into or outside the tower 5 via the first passage 50a, the installation 1 comprises for example a conveyor and a positioning system at the level of the first passage 50a. In the same way, to facilitate the transfer of the parts 2 outside or in the tower 5 by the second passage 50b, the tower 5 comprises for example a traveling crane connecting the second passage 50b and the second entrance 40. An articulated arm or a hook makes it possible to apprehend and position the parts 2 in or outside the tower 5.

The densification enclosure 41 is for example represented in FIG. 3. The enclosure 41 is preferably cylindrical. It comprises a wall 42, for example made of steel, which extends vertically and delimits an interior space 44 in which the batches 20 of parts 2 are arranged. The enclosure 41 further comprises a series of valves 43 allowing the densification gases to be introduced. Since the plates 22 have orifices, the gases can effectively reach the parts 2. The parts 2 are also subjected to a heat treatment in the enclosure 41 at a temperature between 800° C. and 2500° C. depending on the type of desired heat treatment. Preferably, the second input 40 of the second transformation station 4 is provided at level Z1 opposite the enclosure 41. Thus, when the second station 4 comprises a plurality of enclosures 41, each enclosure 41 comprises a second entry 40.

The tower 5 loaded with the densified and heat-treated parts 2 is moved again to return to the first transformation station 3. The heat-treated parts 2 are then deposited within the peeling cell 32.

In the peeling cell 32, the parts 2 are individually subjected to machining making it possible to open the porosities of the composite material of the parts 2 in order to fill the porosities at the very heart of the material. Then the parts 2 are again grouped into batches 20 to be subjected to heat treatment within the densification chamber 41. Tower 5 is used as before to ensure the transfer of parts 2 into enclosure 41. Subsequently, parts 2 are transferred via tower 5 into machining cell 33 to form the brake discs.

A method of manufacturing brake discs for an aircraft will now be described.

In a first step (a) of the method, the parts 2 of brake discs made of composite material as described above are provided within the first processing station 3 as described above. More particularly, in step (a) the parts 2 are provided in the textile cell 31. The parts 2 provided in step (a) are called in the technical field of the invention annular preforms.

The method then preferably comprises a step (a1) of forming batches 20 of coins 2, each batch 20 comprising a plurality of stacks 21 of coins 2, the stacks 21 being arranged on a tray 22 as described previously.

2 pieces, preferably in the form of 20 batches, are loaded in a step (b) in tower 5 from the first level Z0 via the first passage 50a of tower 5.

Tower 5 is then moved during a step (c) to the second station 4 of transformation. The second station 4 comprises in particular one or more enclosures 41 for densification or heat treatment, the second inlet 40 being arranged opposite the upper wall of the enclosure 41.

The swing 52 is then moved in a step (d) to reach the second level Z1 of the installation 1. The swing 52 is preferably moved in rotation and possibly in translation in the support structure 51.

The parts 2 are then transferred in a step (e) to the second processing station 4 from the second level Z1, for example through the second passage 50b of tower 5.

The parts 2 are then transformed in a step (f) to provide brake discs.

Step (f) optionally comprises a step (f1) of heat treatment in the enclosure 41, then a step (f2) of loading the parts 2 into the tower 5 from the second level Z1, followed by a step (f3) of moving the tower 5 towards the first transformation station 3, for example towards the peeling cell 32. Then, a step (f4) of moving the swing 52 to reach the first level Z0 is carried out. The parts 2 are then transferred in a step (f5) to the first station 3 to undergo a peeling operation. Optionally after step (f5), steps (b), (c), (d), (e) and (f) are repeated until the brake discs are obtained in their final shape.

Thus, according to the invention, the manufacture of the brake discs is carried out continuously without break in load between the first station 3 and the second manufacturing station 4. The tower 5 according to the invention makes it possible to distribute the flow of parts 2 in ensuring their storage and transfer between the first level Z0 and the second level Z1.

Claims (10)

Installation (1) for the manufacture of brake discs for an aircraft, formed from a composite material comprising a matrix and a fibrous reinforcement, the installation (1) comprising:

• a first station (3) for converting parts (2) having a first entrance (30) arranged on a first level (Z0) of the installation (1);
• a second station (4) for transforming the parts (2) having a second entrance (40) arranged on a second level (Z1) of the installation (1), the second level (Z1) being raised with respect to the first level ( Z0); And
• a tower (5) for storing and transferring parts (2) able to move between the first station (3) and the second station (4), the tower (5) comprising:
  • a support structure (51) and
  • at least one swing (52) able to move in the support structure (51) to receive the parts (2) from the first station (3) from the first level (Z0) and transfer them to the second station (4) by the second level (Z1).

Installation (1) according to claim 1, characterized in that the storage and transfer tower (5) comprises an interface arranged on the support structure and capable of cooperating with a guided autonomous vehicle to move the tower. Installation (1) according to claim 1 or 2, characterized in that it comprises an electric control device capable of controlling the movement of the storage tower (5) and the movement of the swing (52). Installation (1) according to any one of the preceding claims, characterized in that the storage and transfer tower (5) comprises wheels on which the support structure (51) is mounted. Installation (1) according to any one of the preceding claims, characterized in that the storage and transfer tower (5) comprises a first passage (50a) for the parts (2) giving access to the first level (Z0) and a second passage (50b) of the rooms (2) giving access to the second level (Z1). Installation (1) according to Claim 5, characterized in that the distance (H) separating the first passage (50a) and the second passage (50b) is between 2 m and 20, preferably between 5 m and 10 m. Installation (1) according to any one of the preceding claims, characterized in that the storage and transfer tower (5) comprises a plurality of rows of swings (52) superimposed and distributed over two columns, each of the swings (52) being able to be placed in the support structure (51). Installation (1) according to any one of the preceding claims, characterized in that the support structure (51) has a width (L) of between 2 m and 20 m, preferably between 5 m and 10 m and a depth ( P) less than the width of the support structure, for example between between 2 m and 8 m. A method of manufacturing brake discs for an aircraft, the method comprising the following steps:

• (a) supplying parts (2) made of composite material comprising a matrix and a fibrous reinforcement, within a first processing station (3) having a first inlet (30) arranged on a first level (Z0),
• (b) loading the parts (2) from the first level (Z0) into a storage and transfer tower (5) comprising a support structure (51) and at least one swing (52) movable in the support structure (51),
• (c) moving the storage tower (5) and transfer to a second processing station (4) having a second entrance (40) arranged on a second level (Z1) of the installation (1) raised with respect to the first level (Z0),
• (d) moving the swing (52) so as to reach the second level (Z1),
• (e) transferring the parts (2) to the second processing station (4) from the second level (Z1),
• (f) converting parts (2) to provide brake discs.

Manufacturing process according to the preceding claim, characterized in that the rocker (52) is rotatable in the support structure (51).