Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
  • B60R16/00—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for
  • B60R16/02—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements
  • B60R16/03—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements for supply of electrical power to vehicle subsystems or for
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/32—Arrangement, mounting, or driving, of auxiliaries
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/36—Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2220/00—Application
  • F05D2220/50—Application for auxiliary power units (APU's)
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T50/00—Aeronautics or air transport
  • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

Definitions

• the invention relates to a method of streamlining of components of electrical energy transmission components of an aircraft.
• the invention also relates to an electromechanical architecture capable of implementing such a method and an aircraft comprising electrical energy components arranged according to this architecture.
• the aircraft generally comprise at least one auxiliary power unit on board, also called APU (initials of "Auxiliary Power Unit” in English terminology) or GAP (Auxiliary Power Group initials).
• a GAP is a small turbojet engine, associated with an electric power generator, capable of supplying electrical energy to an electric motor dedicated to moving the aircraft on the ground.
• GAPs thus usually equip aircraft to power various energy-consuming equipment (electric, pneumatic and hydraulic power, air conditioning) on the ground, and to start the main engines.
• a GAP may possibly be restarted and used in flight in case of failure of the air conditioning control system or the electrical distribution.
• a GAP 10 is conventionally composed of a gas generator - comprising an air compressor 1 A1, a combustion chamber 2 of the air mixture A1 and fuel K1, and two turbines 3 and 4 - as well as at least one drive shaft and power 5.
• the second turbine 4 is typically a linked turbine, the most powerful GAP being equipped with a free turbine.
• the stages 3 and 4 of G1 gas expansion provide power to the compressor 1 via the drive shaft 5.
• This shaft 5 is also a power shaft: residual power is indeed available on the shaft 5 to drive equipment when the GAP is operational, for example on the ground or during certain phases of flight, especially at takeoff, landing or in case of potential engine failure. In the case where the turbine 4 is free, the available power is transmitted to the equipment on a drive shaft collinear with the shaft 5.
• a charge compressor 6 is driven by the available power supplied by the shaft 5 to compress incoming air A0.
• This compressor 6 is coupled, for example, to an air conditioning system or a pneumatic pressure system (not shown).
• the shaft 5 is coupled to two alternators 7a and 7b connected in parallel via the pinions P1 to P3 of a relay transmission housing of power 8.
• a mechanical fuse Fa On each drive shaft 9a and 9b of each alternator 7a and 7b, is disposed a mechanical fuse Fa, respectively Fb, for cutting overwires in case of failure of an alternator.
• These fuses may be, for example, toothed jaw or sections to break.
• the electrical current generation means consisting of at least one alternator, is doubled here because the technological security provides functional redundancy and have at best two independent electrical circuits. In general, the equipment is classically doubled and remains independent.
• the start of a GAP is conventionally performed by an electric launcher (not shown) and the starting of the main engines by a pneumatic starter powered by the charge compressor 6 mounted on the drive shaft 5 of the GAP.
• a digital control unit U1 also called FADEC (initials of "Full Authority Digital Engine Control” in English terminology) regulates gear speeds of the 8 transmission power transmission.
• the regulation is carried out by injecting the appropriate amount of fuel K1 into the combustion chamber 2 via a metering device D1.
• This quantity is calculated and applied by the unit U1 as a function of the difference between the speed of the gearbox 8 provided by a speed sensor Cv, and transmitted to the unit U1, and a setpoint value.
• the unit U1 and the power electronics EP1, EP2 are in cable connections or radio LA with the control center of the aircraft, in order to coordinate and anticipate the power controls with the flight conditions. [0013]
• a significant increase in electrical equipment tends to favor the concept of "all electric”.
• the multiplication of equipment involves the use of motors and / or generators superabundant to electrically coordinate equipment, and a multiplication of electromechanical connection systems in relay boxes.
• the architecture becomes complex and energy efficient. In particular, congestion, mass and costs are increased while reliability is decreased.
• the GAP is an addition of significant power source whose use, limited to certain flight phases, results in highly complex real-time circuit switches. in the electric core, in particular to ensure the different functions in case of failure.
• the energy recovered by recycling for example during deceleration on the ground by the landing gear motors (function called "green taxiing" in English terminology, that is to say in green recovery of taxing) or by heat exchangers in suitable locations, can not be used by GAPs in flight phases where they are not operational, start-up and charging authorization times are too long: an additional energy absorption system must be installed.
• the invention aims to overcome these drawbacks and, in particular, to achieve an architecture capable of rationalizing the electrical distribution between different components of an aircraft to reduce the number of components, bulk, mass and costs, while ensuring good reliability.
• the invention proposes to optimize the energy supply by a suitable operation in reversibility of electrical supply systems GAP.
• This operation allows adaptation, in case of failure of the GAP or the pneumatic or hydraulic energy supply system.
• the subject of the present invention is a process for rationalizing the chain of electrical energy transmission components of an aircraft comprising an auxiliary power unit GAP, main engines and end-user equipment for electrical energy. , pneumatic and / or hydraulic controlled by dedicated control systems.
• the GAP provides power delivered on a drive shaft by connecting to at least one energy transforming group via a power transmission housing.
• Each transformer group has only one convertible starter / generator electromechanical component and an associated energy transformer.
• the transmission of power is carried out from the each transformation group by direct connection on the one hand to the transmission box and on the other hand to the dedicated final equipment.
• This method thus eliminates the intermediates (motors, generators, converters, etc.) of electromechanical transformation and reduce the power capacity necessary for the supply of energy to the dedicated final equipment, for example the control systems. air conditioning.
• connection between the transformer unit and the GAP is formed in the housing by coupling the drive shaft of the GAP on the starter / generator DG shaft via a directional power communication operating in a single direction. from the drive shaft of the GAP to the shaft of the DG, the transmission being free or without drive communication in the other direction.
• the method may provide that:
• the DG or one of the DGs is configured to operate in motor mode during the start phase of the GAP, and then drive the GAP via a directional power communication ranging from the group to the GAP;
• the DG then operating in motor mode is advantageously movably connected to the drive shaft of the GAP so that the associated energy transformer is not driven during the starting phase of the GAP;
• an energy recovery turbine by heat exchange at the outlet of hot gases at the outlet of pneumatic equipment and / or main engines, at least partially drives a transformer group by coupling in the power transmission box via at least one minus directional power communication from the recovery turbine to the transformer group;
• the one or one of the transformer groups is dedicated to taxing by supplying electrical energy in coupling with a landing gear motorization of the aircraft and the other group to the supply of energy according to the needs of the aircraft, the group dedicated to taxing being configured to operate in generator mode in connection with the drive shaft of the GAP according to the demand in traction of said engine, and in drive mode of the associated compressor when the train operator is converted into generator mode during the braking phases;
• an additional DG is dedicated to taxing and coupled to the shaft of the GAP in the housing to be driven by this shaft and operate in generator mode according to the traction demand of the train operator, and to operate in engine mode. drive of the GAP shaft itself in engine mode when the train operator is converted into generator mode during the braking phases.
• the invention also relates to an electromechanical architecture comprising electrical energy transmission components in an aircraft, capable of implementing the above method.
• Such an architecture comprises a GAP, a control unit in connection with at least one power electronics, a power transmission case by gear means between, on the one hand, the shafts of at least one transformer unit, integrating by a single DG convertible by the control unit and, on the other hand, a power transmitting GAP drive shaft, as well as direct electrical power links to a final equipment.
• Each transformation group is directly connected, on the one hand, to the power transmission box and, on the other hand, to the dedicated final equipment.
• the transformation unit comprises respectively a compressor, a hydraulic pump or an alternator as an example of an associated energy transformer.
• the power transmission is performed in the transmission housing by coupling the drive shaft of the GAP on the rotation shafts of the starters / generators DG via means of directional power communication mounted on the GAP drive shaft and on the rotation shafts of the DGs.
• the directional power communication means are selected from a freewheel, a decoupling sleeve and a centrifugal or electromechanical clutch;
• control unit is capable of configuring, during the GAP startup phase, the DG of a transformer group in motor mode and driving the GAP tree by coupling to this GAP tree via at least one communication means of directional power;
• the drive of the GAP shaft is made by a mobile coupling means between the DG and the GAP shaft via at least one directional communication means, this coupling means simultaneously performing a disconnection between the DG and the associated power transformer;
• An energy recovery turbine from heat exchangers at the outlet of pneumatic equipment and / or main engines, is coupled to at least one transformer unit in the transmission housing to drive it, in addition to the drive operated by the GAP shaft, via at least one directional power communication means from the recovery turbine to the transformer unit;
• one of the transformer groups dedicated to the taxing by a coupling means on at least one drive shaft of the landing gear engines of the aircraft, another group being dedicated to the supply of energy according to the needs of the aircraft, is configured by the control unit in generator mode in addition to the drive operated by the GAP shaft according to the traction demand of said train engines, and in the drive motor mode of the transformer. energy of this group when the train engines are converted into generator mode by the control unit during the braking phases;
• an additional DG dedicated to taxing, is driven by the GAP shaft by coupling in the transmission box and converted by the transmission unit.
• FIG. 1 a basic diagram of energy distribution architecture comprising two motor compressors in connection with a GAP (already commented);
• FIG. 2 an exemplary architecture diagram according to the invention comprising directional power communication means on the main trees;
• FIG. 3 the architecture diagram according to FIG. 2 applied to the start of the GAP and to the taxing
• FIG. 6 the diagram of a variant of FIG. 3 applied to the taxing with a third DG coupled directly to the GAP;
• FIG. 7 an energy absorption architecture diagram comprising a recovery turbine.
• the illustrated architecture 10 comprises an APU of the type of FIG. 1 with, in the present example, a power turbine 4 of the free turbine drive type of the drive shaft. power 5a.
• the elements identical to those of FIG. 1 are designated by the same references in Figures 2 to 7 (unless expressly indicated).
• the pooling of the functions of the architecture related to the GAP 10 according to the invention is rationalized by bidirectional links L1 and L2 between the control unit U1 and each of the power electronics EP1, EP2 which manages the starter transformation.
• generator or DG of alternators 13a, 13b during different phases: start of the GAP or main engines, energy absorption or taxing.
• the power electronics EP1, EP2 transmit to the unit U1 information on the power level that the alternators must provide to anticipate GAP power supply transients or for a speed optimization search.
• the power electronics EP1, EP2 receive from unit U1 the confirmation signal of the power that can be supplied by the GAP.
• the gas generator consists of the compressor 1, the combustion chamber 2 and a turbine HP (high pressure) 3.
• the latter provides the drive power to the compressor 1 via the shaft
• the speed of the drive shaft 5 is measured by a Cv sensor and the information is transmitted to the control unit U1.
• the gas generator also comprises a free power turbine 4.
• the residual energy leaving the turbine 3 is then transferred to the power turbine 4, a free turbine in the example, which provides mechanical power on the power shaft 5a.
• This power is available to drive equipment, via the transmission housing 8, able to convert this power into pneumatic power, electrical or hydraulic.
• the GAP 10 thus provides pneumatic power by driving charge compressors 1 1a and 1 1b and the electrical power by driving alternators 13a and 13b.
• Other equipment shown in dotted lines may be driven, including a hydraulic pump and / or an alternator and / or a starter / generator DG dedicated to taxing (see below with reference to Figure 5).
• the shaft 5a transmits the power to the pinion P1 through a freewheel RL1.
• the arrow F1 indicates the active communication direction of the power transmitted by the freewheel RL1.
• the power transmission thus passes from the shaft 5a to the pinion P1, without being transmitted in the opposite direction, that is to say, pinion P1 to the shaft 5a.
• the engagement E1 of the freewheel RL1 being active, by construction, only in one direction of rotation corresponding to the direction of transmission of the arrow F1, no catch is engaged in the opposite direction and therefore no transmission pinion P1 to the shaft 5a is possible.
• the arrows F2 and F3 indicate the direction of active power communication imposed by the freewheels RL2 and RL3, that is to say respectively of the pinion P2 to the pinion P4 and the pinion P3 to the pinion P6.
• the compressors 1 1a and 1 1b which produce the pneumatic energy, are respectively driven by shafts 15a and 15b of pinions P5 and P7, via fusible shafts AF3 and AF4, the pinions. P5 and P7 are respectively geared by the pinions P4 and P6 alternators 13a and 13b.
• Each alternator 13a, 13b respectively drives a compressor 1 1a, 1 1b: each pair consisting of an alternator 13a, 13b and the corresponding compressor 1 1a, 1 1b form a motor-compressor MC1, MC2.
• the free wheel RL1 is a redundancy of the uncoupling function exerted by the freewheels RL2 and RL3. It can possibly be suppressed, in particular in case of additional redundancy of alternators and / or compressors.
• a decoupling sleeve may be introduced on the shaft 5a. Such a sleeve is described in the patent document FR 2,887,945 incorporated by reference.
• the architecture of the invention allows pooling equipment and start functions of the GAP and recovery or energy absorption.
• FIG. 3 repeats and completes the architecture of FIG. 2 to illustrate the implementation of a starting solution of the GAP by one or other of the alternators, for example the alternator 13b.
• the alternator 13b converted into a starter, by calling this function by the associated power electronics EP2, drives the shaft 5 via the series of pinions P6, P7, P8 and P9: the pinion P6 mounted on the shaft 15b of the alternator 13b meshes with the pinion P7 which drives the compressor 1 1b and a freewheel RL4.
• the arrow F4 indicates the direction of the freewheel RL4, that is to say a power communication is transmitted to the pinion P8.
• the latter meshes with the P9 pinion geared on the shaft 5 of the GAP 10.
• the power between the pinions P7 and P8 is transmitted via a decoupling sleeve MD1.
• This fuse can be that of the technology used to drive the air motor starters. They are able to transmit strong torque through a fuse calibrated accordingly in the direction of the arrow F5 (P7 pinion to the pinion P8) but, conversely, it behaves weak fuse if the transmission of power is in the opposite direction. This device avoids driving the gas generator in case of failure of the freewheel RL4.
• Figure 4 illustrates a variant for performing the start function without driving the compressor 1 1b during the start phase of the GAP, and therefore reduce the power to be supplied during this phase.
• a movable pinion P10 of shaft 12b carrying the decoupler sleeve MD1 is inserted between the pinions P6 and P7.
• the pinion P6 drives, by a wide toothing, the pinion P10, which does not mesh the pinion P7 with teeth that is appreciably narrower than that of the pinion P6.
• the decoupler sleeve MD1 the power is transmitted to the pinion P8 which drives the pinion P9.
• the pinion P8 is also mobile along its tree coincident with the tree 12b of the pinion 10, so that all of the two pinions P8-P10 constitutes a directionally movable gear train in translation.
• FIG. 5 shows the same solution after the start-up phase, that is to say in power supply configuration by the GAP 10.
• the gear train P10 and P8 connected by the decoupler sleeve MD1 is translated so that it is no longer in mesh with the pinion P9 of the GAP shaft.
• the GAP transmits power via its shaft 5a in the basic configuration illustrated in FIG.
• This solution may advantageously include synchromes (not shown) of angle measurement for a restart of the GAP in residual rotation, for example, an autorotation by "reel effect” or end of start sequence then that the free turbine 4 is accelerated at low speed.
• the functional pooling of the equipment according to the invention in particular by the shared management of the generators 13a and / or 13b and the compressors 11a and / or 11b by the power electronics EP1 / EP2 in bidirectional link L1 / L2 with FADEC U1 - allows the rational implementation of power absorption recovery.
• This recovery comes for example braking phases of the landing wheels, during the phases of taxing and / or landing, or, for example, an associated recovery turbine.
• the alternators 13a and 13b of Figures 2 to 5 are advantageously converted into engines - starter function through power electronics EP1 and EP2 - to absorb the powers supplied by the engines of the wheels of the main gear converted into generators.
• the alternator 13a which is not dedicated to starting the GAP (as well as to the supply of power after starting), can be dedicated to this absorption function. power.
• the energy required for the displacement of the aircraft is provided by the generator 13a.
• the electric motors of the train are converted into alternators and supply electrical power to the alternator 13a as a motor (starter function) transmitted through additional pinions Ps.
• This power is transmitted through the pinions P4 and P5 to the compressor 1 1a to recover the energy in pneumatic form.
• the additional energy that may be required to drive the compressor 11a is provided by the power turbine 4 of the GAP 10.
• the shaft 5a is no longer driven and therefore no longer drives the pinion P1.
• the alternator 13a converted into a motor provides the mechanical power necessary to drive the charge compressor 1 1 a and other equipment if necessary.
• the alternator 13b can be converted into a motor to provide the mechanical power needed to drive the charge compressor 11b and other equipment.
• the two sets of alternators and compressors, 13a / 1 1a and 13b / 1 1b, which form two independent sets equivalent to two motor-compressors, MC1 and MC2, can be used in case of failure GAP. This avoids the addition of two other systems in relief. The reliability of the pinion coupling system is sufficient to meet safety requirements.
• the GAP fails in flight - or to ensure the continuity of supply of compressed air during the start phase of the GAP - it is advantageous to use the motor-compressor systems MC1 or MC2 without starting the GAP 10.
• the MC1 motor-compressor system is operational, and the second MC2 motor-compressor ensures the launch of the GAP for its start-up.
• FIG. 6 illustrates, as a power absorption architecture variant during the taxing and / or landing operations, the installation of a convertible alternator or additional DG 13c dedicated to this function.
• the reduction by a gear train on the transmission shaft 14c of the DG 13c, between the DG 13c and the shaft 5a of the GAP 10, is not shown in the diagram to avoid overloading the figure.
• the AF5 mechanical fuse protects the shafts against the presence of possible overcouples.
• the energy required for the movement of the aircraft is provided by the DG 13c generator mode (alternator) driven by the GAP 10. This energy is then transmitted to the electric motors of the wheels of the train.
• the electric motors of the wheels are transformed into alternators. They then supply electrical energy (transmitted through known electrical power devices) to DG 13c converted to motor mode. This energy is transmitted through the fuse AF5 to the shaft 5a. The power supply requirement of the power turbine 4 is thereby reduced.
• FIG. 7 Another example of power absorption is illustrated by the diagram of Figure 7.
• the configuration shows a GAP 10 in connection with a recovery turbine 16a.
• the recovered power is transmitted on a power shaft 17 through a decoupling sleeve MD2 in the direction of the arrow F6, that is to say from the turbine 16a to a gear pinion P12 of the transmission housing 8 .
• This decoupler sleeve MD2 avoids driving the turbine 16a in case of non-production of power during different phases of use of the aircraft (eg open door).
• a freewheel RL5 transmits the power of the turbine shaft 17 to the pinion P12 which meshes with the pinions P5 and P4 of the motor-compressor MC1.
• the decoupler sleeve MD2 then makes it possible to avoid driving the turbine 16a in the event of failure of the free transmission wheel RL5.
• the freewheel RL2 makes it possible not to drive the power turbine 4 by the motor-compressor unit MC1 or MC2.
• the two recovery turbines 16a and 16b are symmetrically coupled to the two motor-compressor systems MC1 / MC2 in the housing 8: shafts 17/18, fuses MD2 / MD3, RL5 / RL6 freewheels, P12-P5-P4 / P13-P7-P6 sprockets.
• the arrangement of the box 8 is adaptable by the number of gears and reduction ratios.
• the gearbox can be broken down into several parts: a main box with a series of power take-offs by motor-compressor unit, and a box by motor-compressor group, with or without recovery turbine.
• the convertible alternators and the compressors of the motor-compressors may be on the same shaft line, or, the compressor and the recovery turbine being on two lines, the alternator is integrated into the gearbox in the form of a removable cartridge. .
• the position of the freewheels and fuses can also be adapted. Suitable clutches, for example centrifugal or electromechanical clutches, can replace the sleeves or freewheels.
• the power turbine is a linked turbine, the two traversing shafts 5a and drive 5 are inherently linked
• the architecture may have only one convertible alternator and only one charge compressor, that is to say a single motor-compressor.
• the compressed air supply system on aircraft can be provided by other means than those described. The redundancy of this main system can be ensured by an additional motor-compressor system, in order to meet the safety objectives.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
• Control Of Eletrric Generators (AREA)
• Engine Equipment That Uses Special Cycles (AREA)
• Transmission Devices (AREA)

Applications Claiming Priority (2)

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Citations (1)

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• 2011
  • 2011-05-20 FR FR1154431A patent/FR2975547B1/fr active Active
• 2012
  • 2012-05-15 KR KR1020137032401A patent/KR101986856B1/ko active IP Right Grant
  • 2012-05-15 CA CA2836027A patent/CA2836027C/fr not_active Expired - Fee Related
  • 2012-05-15 US US14/118,076 patent/US9555752B2/en active Active
  • 2012-05-15 CN CN201280023892.6A patent/CN103547779B/zh not_active Expired - Fee Related
  • 2012-05-15 JP JP2014510862A patent/JP6212483B2/ja not_active Expired - Fee Related
  • 2012-05-15 RU RU2013154396A patent/RU2610358C2/ru active
  • 2012-05-15 WO PCT/FR2012/051085 patent/WO2012160294A1/fr active Application Filing
  • 2012-05-15 EP EP12728693.8A patent/EP2710245A1/de not_active Withdrawn

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