Abstract: A system and a method for controlling an aircraft engine starter/generator. The system includes an AGB of fixed gear ratio for coupling mechanically to a turbine shaft of the engine to enable the engine to be started, a gearbox having multiple gear ratios mechanically coupled to a gearwheel of the AGB, a starter/generator mechanically coupled to a gearwheel of the gearbox, and a controller to cause the gear ratio of the gearbox to be changed as a function of the mode of operation of the starter/generator.

Abstract: A method of determining the angular position of a first rotor of a turbojet. A vibration pulse is generated during a rotation of the first rotor, each vibration pulse being generated when the first rotor passes through a given reference angular position. The vibration generated is detected. The angular position is obtained at a given instant of a second rotor of the turbojet relative to the angular position that it occupied at a reference instant representative of detecting a vibration pulse. The second rotor is coupled in rotation with the first rotor and has a speed of rotation different from the speed of rotation thereof. The angular position of the first rotor at the given instant is determined from the angular position of the second rotor.

Abstract: A method for producing the electrical power required for equipment on board an airplane is disclosed. Auxiliary power is taken off by a shaft driven by the high pressure turbine and, when idling, the efficiency of the low pressure turbine is degraded so as to enable the high pressure turbine to operate at a speed that is sufficient for delivering the required auxiliary power.

Abstract: A method of providing a standby lubrication for an engine in the event of the failure of a main lubrication system of this engine, in which the failure is detected and, in response to the detection of this failure, at least one portion of a fuel fluid of the engine is tapped off to lubricate at least one element of the engine. A standby lubrication device includes a device for detecting a failure of a main lubrication system, a device for tapping off at least a portion of a fuel fluid of the engine in order to direct it to at least one element of the engine intended to be lubricated, and a controller connected to the tapping and detection devices, in order to carry out the standby lubrication method.

Abstract: A system and a method for controlling an aircraft engine starter/generator. The system includes an AGB of fixed gear ratio for coupling mechanically to a turbine shaft of the engine to enable the engine to be started, a gearbox having multiple gear ratios mechanically coupled to a gearwheel of the AGB, a starter/generator mechanically coupled to a gearwheel of the gearbox, and a controller to cause the gear ratio of the gearbox to be changed as a function of the mode of operation of the starter/generator.

Abstract: A device for driving the rotor of an auxiliary is mounted on a turbine engine auxiliaries support which includes a pinion for driving the rotor shaft. The device includes a tubular shaft driven by the pinion and supported by a first bearing (18) and a second bearing (19) which are secured to the auxiliaries support (10). The rotor shaft is coaxial with the tubular shaft and a splined coupling portion formed between the rotor shaft and the tubular shaft. By virtue of the invention, mechanical loads of the auxiliary are transmitted to a lesser extent to the rotor shaft support bearings and to the auxiliaries support gear train.

Abstract: The invention relates to a method of determining the angular position of a first rotor of a turbojet, the method consisting in: generating at least one vibration pulse during a rotation of the first rotor, each vibration pulse being generated when the first rotor passes through a given reference angular position; detecting the vibration generated thereby; obtaining (E30) the angular position at a given instant of a second rotor of the turbojet relative to the angular position that it occupied at a reference instant representative of detecting a vibration pulse, said second rotor being coupled in rotation with the first rotor and having a speed of rotation different from the speed of rotation thereof; and determining (E40) from the angular position of the second rotor, the angular position of the first rotor at said given instant.

Abstract: A system for attaching the end of a shaft of a gas turbine engine engaged inside a coupling supported by a bearing is disclosed. The system includes a nut with a first thread which is screwed into the shaft and a second thread which is screwed to the coupling. Advantageously, the screw pitches of the two threads of the nut are reversed relative to one another so as to form an adjusting nut.

Abstract: An assembly includes a gearbox for a gas turbine having a geartrain, and at least one starter/generator coupled mechanically to the gearbox. The starter/generator includes a generator module with a first casing, a generator housed in the first casing, and a first shaft constrained to rotate with the rotor of the generator, projecting from the first casing, and carrying a first mechanical coupling member; an exciter module, including a second casing, an exciter housed in the second casing, and a second shaft distinct from the first shaft, constrained to rotate with the rotor of the exciter, projecting from the second casing, and carrying a second mechanical coupling member; and an electrical connection including a rectifier and at least one connector for connecting the secondary circuit of the exciter to the primary circuit of the generator.

Abstract: Producing the electrical power need for equipment on board an airplane. Auxiliary power is taken off by means of a shaft driven by the high pressure turbine and, when idling, the efficiency of the low pressure turbine is degraded so as to enable the high pressure turbine to operate at a speed that is sufficient for delivering the required auxiliary power.

Abstract: A gas-turbine starter/generator comprises: a generator module comprising a first casing, a generator housed in the first casing, and a first shaft constrained to rotate with the rotor of the generator, projecting from the first casing, and carrying a first mechanical coupling member; an exciter module, comprising a second casing, an exciter housed in the second casing, and a second shaft distinct from the first shaft, constrained to rotate with the rotor of the exciter, projecting from the second casing, and carrying a second mechanical coupling member; and an electrical connection comprising a rectifier and at least one connector for connecting the secondary circuit of the exciter to the primary circuit of the generator. The mechanical coupling members are coupled to a common gearwheel or to respective different gearwheels of a gearbox of the gas turbine.

Abstract: The invention relates to a standby lubrication method for an engine 1 in the event of the failure of a main lubrication system 2 of this engine 1, in which said failure is detected and, in response to the detection of this failure, at least one portion of a fuel fluid of the engine 1 is tapped off to lubricate at least one element of the engine 1. The invention also relates to a standby lubrication device 6 for an engine 1 comprising a main lubrication system 2, said standby lubrication device 6 comprising means for detecting a failure of the main lubrication system 2, means 12 for tapping off at least a portion of a fuel fluid of the engine 1 in order to direct it to at least one element of the engine 1 intended to be lubricated, and control means 15 capable of being connected to said tapping and detection means 12, in order to carry out the standby lubrication method.

Abstract: The device for driving the rotor of an auxiliary (11) of the invention is mounted on a turbine engine auxiliaries support (10) which comprises means (15) for driving the rotor shaft (13). It comprises a tubular shaft (17) driven by one of said means (15) and supported by a first bearing (18) and a second bearing (19) which are secured to the auxiliaries support (10), the rotor shaft (13) being coaxial with the tubular shaft (17) and a rotational-coupling means being formed between the rotor shaft (13) and the tubular shaft (17). By virtue of the invention, mechanical loads of the auxiliary (11) are transmitted to a lesser extent to the rotor shaft support bearings (18, 19) and to the auxiliaries support gear train.

Abstract: The invention relates to a system for attaching the end of a shaft (14) of a gas turbine engine engaged inside a coupling (15) supported by a bearing (3). Said system comprising a nut (16) is characterized in that the nut (16) comprises a first thread (16f1) by which it is screwed into said shaft (14) and a second thread (16f2) by which it is screwed to said coupling (15). Advantageously, the screw pitches of the two threads (16f1, 16f2) of the nut (16) are reversed relative to one another so as to form an adjusting nut.

Abstract: A device for ensuring the sealing in a rotary machine between a rotor and fixed blade stages.Blade edges are joined by rings carrying circular seals in slots. Springs force the seals in the longitudinal direction towards transverse faces of reinforcements of the rotor.A turbulence-free gas flow is obtained as a result of the total seal obtained by the seals (19). Moreover, the rotor can be constructed with a substantially rectilinear ferrule which only induces limited stress concentrations.