Patent Publication Number: US-2023143382-A1

Title: Bypass turbine engine comprising at least one accessory or equipment

Description:
TECHNICAL FIELD 
     The invention relates to a bypass turbine engine comprising at least one accessory or equipment, such as an oil pump, a fuel pump or even a hydraulic pump. 
     STATE OF THE PRIOR ART 
     Conventionally, a bypass turbine engine comprises a fan intended to suck in a gas stream which is divided, downstream of the fan, into a primary gas stream circulating in a primary stream flow channel, called primary flow path, within a core of the turbine engine extending along a longitudinal axis of axial direction, and into a secondary gas stream bypassing this core in a secondary stream flow channel, called secondary flow path. 
     In the primary flow path, the primary gas flow passes through, from upstream to downstream in the axial direction of gas flow, a low pressure compressor, a high pressure compressor, a combustion chamber, a high pressure turbine, a low turbine pressure and an exhaust nozzle. In the secondary flow path, the secondary air stream passes through a fan rectifier. 
     The low pressure compressor and the low pressure turbine are connected by a first shaft, called the low pressure shaft, rotating about the longitudinal axis, while the high pressure compressor and the high pressure turbine are connected by a second shaft, called high shaft pressure, rotating around the low pressure shaft. The low pressure shaft and the high pressure shaft are both part of the core of the turbine engine. 
     When the turbine engine has a relatively high by-pass ratio, also called “BPR”, it may be advantageous for the fan to be mechanically driven by the low pressure shaft via a reduction gear. 
     In order to lubricate and cool this reduction gear, it is known to equip the turbine engine with a lubrication system, in particular an oil circuit comprising an oil tank and a lubrication pump which is mechanically driven by a transmission gear box, also called Accessory Gear Box or “AGB”, and which draws mechanical power from the high pressure shaft via an intermediate shaft, called “RDS” for “Radial Drive Shaft”. 
     However, in the “windmilling” phase of the turbine engine which corresponds to an autorotation of the fan, the speed of rotation of the high pressure shaft is low relative to that of the low pressure shaft. The mechanical power taken from the high pressure shaft and transmitted to the oil pump may thus not be sufficient to allow the oil pump to deliver the oil required for the lubrication and cooling of the reduction gear, which is nevertheless biased by the autorotation of the fan and which therefore risks being damaged or even to break. 
     If the turbine engine does not comprise a reduction gear, it is also possible that during the “windmilling” phase, the oil pump rotates too slowly to deliver all oil required for the lubrication and cooling of the bearings which support the high and low pressure shafts. An auxiliary lubrication system, for example using a second oil pump, may then be required. A single oil pump is generally provided, but its sizing is impacted by the constraints of the lubrication during the low rotational speeds of the high pressure shaft. 
     Whether or not the turbine engine comprises a reduction gear, the lubrication constraints during the low rotational speeds of the high pressure shaft have a significant impact on the sizing, and therefore the space requirement and the mass, of the lubrication system driven by the mechanical power drawn from the high pressure shaft. 
     Similar difficulties can be found at low speeds concerning other accessories, such as a fuel pump of the turbine engine. 
     DISCLOSURE OF THE INVENTION 
     The invention aims at overcoming the drawback mentioned below, by proposing a bypass turbine engine comprising a low pressure shaft, a high pressure shaft and an electrical energy generator assembly which draws off mechanical power, on the one hand, from the low pressure shaft via a first intermediate shaft, and on the other hand, from the high pressure shaft via a second intermediate shaft, to power one or more accessories, such as an oil pump, with electrical energy. 
     More specifically, the invention relates to a bypass turbine engine comprising, from upstream to downstream in an axial direction of gas flow, a fan and a splitter nose from which originate a primary stream flow channel, called primary flow path, and a secondary stream flow channel, called secondary flow path, which surrounds the primary flow path, the turbine engine further comprising:
         a fixed casing comprising an arm which extends radially, relative to the longitudinal axis, in the secondary flow path,   a first shaft, called low pressure shaft, designed to rotate relative to the casing about a longitudinal axis oriented in the axial direction of gas flow,   a second shaft, called high pressure shaft, designed to rotate relative to the casing around the low pressure shaft, the high pressure and low pressure shafts being concentric,   at least one accessory driven by a motor,   an upper portion via which the turbine engine is intended to be attached to an aircraft,   an opposite lower portion in a vertical direction orthogonal to the longitudinal axis, the arm extending generally vertically, in the lower portion, in the secondary flow path,   a first intermediate shaft designed to draw mechanical power from the low pressure shaft,   a second intermediate shaft designed to draw mechanical power from the high pressure shaft,   an electrical energy generator assembly housed in the arm and coupled, on the one hand, to the first intermediate shaft and, on the other hand, to the second intermediate shaft, so as to receive mechanical power from the first intermediate shaft, on the one hand, and from the second intermediate shaft, on the other hand, the generator assembly being further designed to convert the mechanical power received from the first and second intermediate shafts into electrical energy in order to power the motor(s) driving the accessory or accessories, the electrical energy powering the motor(s) driving the accessory or accessories thus originating simultaneously from the mechanical power drawn from the low pressure shaft and the mechanical power drawn from the high pressure shaft.       

     According to variant embodiments which can be taken together or separately:
         the first and second intermediate shafts are coaxial and each designed to rotate, independently of each other, relative to the casing about the same intermediate axis;   the secondary flow path is delimited radially, relative to the longitudinal axis, by an outer shroud and an inner hub of the structural casing, the outer shroud and the hub being concentric and centred on the longitudinal axis;   the arm, which houses the generator assembly, extends radially, relative to the longitudinal axis, between the outer shroud and the hub;   the arm houses, upstream in the axial direction of gas flow, ancillaries and, downstream in the axial direction of gas flow, the generator assembly;   the generator assembly comprises:
           a first drive shaft designed to draw mechanical power from the first intermediate shaft and to rotate relative to the casing about a first drive axis,   a second drive shaft designed to draw mechanical power from the second intermediate shaft and to rotate relative to the casing about a second drive axis, the first and second drive shafts being coaxial and each designed to rotate, in an opposite direction of rotation, about the first and second drive axes then coincident,   one or more first alternator(s) each comprising an inductor rotor mounted secured in rotation with one of the first and second drive shafts about the first and second drive axes and an induced rotor mounted secured in rotation with the other of the first and second drive shafts about the first and second drive axes,   one or more second alternators each comprising an inductor rotor mounted secured in rotation, about the first and second drive axes, with that of the first and second drive shafts which is surrounded by the other of the first and second drive shafts, and an induced stator which is fixed relative to the inductor rotor of said second alternator;   
           first and second drive axes are oriented generally in the axial direction of gas flow;   the generator assembly comprises:
           a third drive shaft designed to draw mechanical power from the first drive shaft and to rotate relative to the casing about a third drive axis,   a fourth drive shaft designed to draw mechanical power from the second drive shaft and to rotate relative to the casing about a fourth drive axis, the third and fourth drive shafts being coaxial and each designed to rotate, in an opposite direction of rotation, about the third and fourth drive axes then coincident,   one or more third alternators each comprising an inductor rotor mounted secured in rotation with one of the third and fourth drive shafts about the third and fourth drive axes and an inductor rotor mounted secured in rotation with the other of the third and fourth drive shafts about the third and fourth drive axes,   one or more fourth alternators each comprising an inductor rotor mounted secured in rotation, about the third and fourth drive axes, with that of the third and fourth drive shafts, and an induced stator which is fixed relative to the inductor rotor of said fourth alternator.   
           the longitudinal axis and the first, second, third and fourth drive axes are comprised in the same plane;   the third and fourth drive axes are respectively parallel to the first and second drive axes;   the first and second drive axes are oriented generally in the axial direction of gas flow, the third and fourth drive shafts being located radially outside relative to the longitudinal axis, while the first and second drive shafts are located radially inside   the first alternator(s) are located upstream in the axial direction of gas flow and the second alternator(s) are located downstream in the axial direction of gas flow or   the first and third alternators are located upstream in the axial direction of gas flow, and the second and fourth alternators are located downstream in the axial direction of gas flow.   the first alternator(s) and the second alternator(s) are respectively housed in a first housing and in a second housing themselves housed in the arm, the first housing having a transverse dimension, taken in a transverse direction, generally horizontal, perpendicular to the axial dimension of gas flow, which is greater than that of the second housing; and/or   the third alternator(s) and the fourth alternator(s) are respectively housed in the first housing or a third housing itself housed in the arm and in the second housing or a fourth housing itself housed in the arm, the third housing having a transverse dimension, taken in a transverse direction, generally horizontal, perpendicular to the axial dimension of gas flow, which is greater than that of the fourth housing;   the first housing and/or the third housing is arranged in contact with a wall of the arm;   the generator assembly comprises:
           an inner drive shaft designed to rotate relative to the casing about a drive axis and to draw mechanical power from the first intermediate shaft or from the second intermediate shaft,   an outer drive shaft designed to rotate relative to the casing around the inner drive shaft in an opposite direction of rotation and to draw mechanical power from the second intermediate shaft or from the first intermediate shaft, the inner and outer drive shafts being concentric,   one or more alternators each comprising an inner body, inductor or induced, mounted secured in rotation with the inner drive shaft about the drive axis and an outer body, induced or inductor, mounted secured in rotation with the outer drive shaft about the drive axis and located opposite to the inner body;   
           the drive axis is oriented generally radially relative to the longitudinal axis; or   the drive shaft is oriented generally along the axial direction of gas flow;   the turbine engine further comprises a regulation system through which the generator assembly delivers electrical energy to the accessory or accessories;   the secondary flow path is separated from the primary flow path by an inter-flow path compartment in which the accessory or accessories are housed;   the accessory or accessories are selected from:
           an oil pump,   a fuel pump,   a hydraulic pump.   
               

    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Other aspects, aims, advantages and features of the invention will appear better on reading the following detailed description of preferred embodiments thereof, given by way of non-limiting example, and made with reference to the appended drawings in which: 
         FIG.  1    is a schematic view, in longitudinal section, of a bypass turbine engine according to a first embodiment of the invention; 
         FIG.  2    is a schematic view, in longitudinal section, of a bypass turbine engine according to a second embodiment of the invention; 
         FIG.  3    is a schematic view, in longitudinal section, of a bypass turbine engine according to a third embodiment of the invention; 
         FIG.  4    is a schematic view, in tangential section, of an arm of the turbine engine illustrated in  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION 
       FIGS.  1  to  3    show a bypass turbine engine  100 A,  1008 ,  100 C of an aircraft respectively according to first, second and third embodiments of the invention. The components common to these three embodiments of the invention bear the same references. 
     Preliminarily, there are defined an axial direction, a radial direction which is orthogonal to the axial direction and a circumferential direction which is orthogonal to the axial and radial directions. 
     In the remainder of the description, the terms “upstream” and “downstream” are used with reference to the axial direction of gas flow. 
     A vertical direction is also defined, which is orthogonal to the longitudinal direction and oriented from bottom to top. 
     The turbine engine  100 A,  1006 ,  100 C comprises, from upstream to downstream, an air inlet  101 , a fan  102  and a splitter nose  103  from which originate an annular primary stream flow channel  104 , called primary flow path, formed within a core of the turbine engine  100 A,  1006 ,  100 C extending along a longitudinal axis  105  oriented axially, and a secondary stream flow channel  106 , called secondary flow path, surrounding the primary flow path  104  and separated from the primary flow path  104  by an inter-flow path compartment  107 . The primary flow path  104  and the secondary flow path  106  are centred on the longitudinal axis  105 . 
     The turbine engine  100 A,  1006 ,  100 C is further faired by a nacelle  108  which surrounds the secondary flow path  106  and which is intended to be fastened to the aircraft at the upper portion thereof. The nacelle  108 , in particular, comprises a fan casing  109  which surrounds the fan  102  and which defines, upstream of the fan  102 , the air inlet  101 . 
     The primary flow path  104  itself comprises, from upstream to downstream, a low pressure compressor  110 , a high pressure compressor  111 , a combustion chamber  112 , a high pressure turbine  113 , a low pressure turbine  114  and an exhaust nozzle  115 . The secondary flow path  106  comprises a fan rectifier  116 , also called “OGV” for “Outlet Guide Vane”. 
     The turbine engine  100 A,  1006 ,  100 C further comprises a fixed casing  117 ,  118 ,  121  itself comprising an outer shroud  117  and an inner hub  118  located downstream of the splitter nose  103 . The outer shroud  117  and the hub  118  are concentric and centred on the longitudinal axis  105 . 
     The hub  118  comprises an outer annular wall  119  which delimits, with the outer shroud  117 , the secondary flow path  106  and an inner annular wall  120  which delimits the primary flow path  104 . The outer shroud  117  thus surrounds the secondary flow path  106  which surrounds the hub  118 . The hub  118  itself surrounds the primary flow path  104 . 
     The outer shroud  117  thus partially forms the nacelle  108 . It is for example located downstream of the fan casing  109 . 
     The outer annular wall  119  and the inner annular wall  120  further together delimit the inter-flow path compartment  107 . 
     The casing also comprises a plurality of arms  121  which extend radially, relative to the longitudinal axis  105 , between the outer shroud  117  and the hub  118 , in particular the outer annular wall  119  of the hub  118 , and which are evenly distributed about the longitudinal axis  105 . 
     One of the arms  121  is for example located at 6 o&#39;clock by analogy with the dial of a clock. In other words, this arm  121  is located in the lower portion of the turbine engine  100 A,  100 B,  100 C and extends both radially and vertically between the outer shroud  117  and the hub  118 . 
     The arms  121 , for example, themselves form blades of the fan rectifier  116 . Alternatively (not represented), the arms  121  are located downstream of the fan rectifier  116 . 
     The arms  121  can house ancillaries (not represented), such as conduits, pipes, electrical harnesses, etc. 
     The turbine engine  100 A,  100 B,  100 C also comprises a first shaft  122 , called low pressure shaft, designed to rotate relative to the casing  117 ,  118 ,  121  about the longitudinal axis  105 , as well as a second shaft  123 , called high pressure shaft, designed to rotate relative to the casing  117 ,  118 ,  121  around the low pressure shaft  122 . The low and high pressure shafts  122 ,  123  are concentric. 
     The low pressure shaft  122  and the high pressure shaft  123  are both part of the core of the turbine engine  100 . 
     For example, the low pressure shaft  122  connects the low pressure compressor  110  and the low pressure turbine  114 , while the high pressure shaft  123  connects the high pressure compressor  111  and the high pressure turbine  113 . 
     The low pressure shaft  122  also drives the fan  102  in rotation about the longitudinal axis  105 , relative to the casing  117 ,  118 ,  121 , for example via a reduction gear  124 . The fan  102  is thus indirectly driven by the low pressure shaft  122 . Alternatively (not represented), the fan  102  can be directly driven by the low pressure shaft  122 . 
     The low pressure shaft  122  and the high pressure shaft  123  are for example designed to rotate about the longitudinal axis  105  in the same direction of rotation. This is, in particular, the case of the low and high pressure shafts  122 ,  123  of the turbine engine  100 C of the third embodiment ( FIG.  3   ). Alternatively, the low pressure shaft  122  and the high pressure shaft  123  are designed to rotate about the longitudinal axis  105  in opposite directions of rotation. 
     The turbine engine  100 A,  1006 ,  100 C is further equipped with one or more accessories or equipment, such as an oil pump  125 , a fuel pump  126  or even a hydraulic pump. Of course, this list is not exhaustive. 
     The oil pump  125  is for example designed to deliver oil originating from an oil reservoir (not represented) to the reduction gear  124 , and/or to bearings (not represented) which support the low and high pressure shafts  122 ,  123  and which are carried by the casing  117 ,  118 ,  121 . The oil pump  125  thus allows ensuring the lubrication and the cooling of the reduction gear  124  and/or the bearings, and therefore the cooling of the turbine engine  100 A,  1006 ,  100 C. 
     The fuel pump  126  is for example designed to deliver fuel to the combustion chamber  112  for the combustion of gases within said combustion chamber  112 . 
     The accessory or accessories  125 ,  126  are further designed to be mechanically driven by a motor (not represented) powered with electrical energy. This motor is thus designed to drive in movement a movable portion of the accessory  125 ,  126 , for example a rotating portion such as the rotor of a pump. This motor can be integrated into the accessory  125 ,  126 , the motor and the accessory  125 ,  126  that it drives, thus forming a one-piece assembly. Alternatively, the motor can be independent or even separate from the accessory or accessories  125 ,  126  that it drives. 
     The accessories  125 ,  126  are for example housed in the inter-flow path compartment  107 . Alternatively (not represented), the accessories  125 ,  126  are housed in the nacelle  108 . Still alternatively (not represented), a portion of the accessories  125 ,  126  is housed in the inter-flow path compartment  107  and another portion of the accessories  125 ,  126  is housed in the nacelle  108 . 
     According to the invention, the turbine engine  100 A,  1006 ,  100 C further comprises a first intermediate shaft  127  designed to draw mechanical power from the low pressure shaft  122 , a second intermediate shaft  128  designed to draw mechanical power from the high pressure shaft  123  and an electrical energy generator assembly  129  coupled, on the one hand, to the first intermediate shaft  127  and, on the other hand, to the second intermediate shaft  128 , so as to receive mechanical power from the first intermediate shaft  127 , on the one hand, and from the second intermediate shaft  128 , on the other hand. The generator assembly  129  is further designed to convert the mechanical power received from the first and second intermediate shafts  127 ,  128  into electrical energy and to power the motor(s), driving the accessory or accessories  125 ,  126 , such as the oil pump  125  and/or the fuel pump  126 , with electrical energy. 
     In this manner, the electrical energy supplied to the accessory or accessories  125 ,  126 , via the motor(s) which drive it or them, originates simultaneously from the mechanical power drawn from the low pressure shaft  122  and from the mechanical power drawn from the high pressure shaft  123 . 
     Thus, in the “windmilling” phase of the turbine engine  100 A,  1006 ,  100 C which corresponds to an autorotation of the fan  102 , even if the high pressure shaft  123  rotates less quickly than the low pressure shaft  122 , the total mechanical power drawn from the low pressure shaft  122  and from the high pressure shaft  123  is sufficient to power the accessory or accessories  125 ,  126  with electrical energy, via the motor(s) which drive it or them. This allows, in particular, ensuring that the oil pump  125  delivers the oil required for the lubrication and cooling of the reduction gear  124  which is biased by the autorotation of the fan  102  and which would otherwise risk being damaged, or even to break. 
     Thus, depending on the operating phase of the turbine engine  100 A,  100 B,  100 C, the generator assembly  129  can as well draw mechanical power from the low pressure shaft  122  only, from the high pressure shaft  123  only or from both the low pressure shaft  122  and the high pressure shaft  123 . The generator assembly  129  therefore operates either on the speed of the low pressure shaft  122 , or on the speed of the high pressure shaft  123 , or in hybrid on the two speeds. 
     The generator assembly  129  thus replaces a transmission gear box, also called Accessory Gear Box or “AGB”, which is known to be implemented to mechanically drive the accessory or accessories  125 ,  126  by drawing mechanical power from the high pressure shaft  123 . This allows in particular reducing the lubrication requirements and therefore reducing the volume of the oil reservoir. The generator assembly  129  can further be electrically powered and controlled to operate in motor mode, in order to advantageously replace the starter which usually mechanically drives the high pressure shaft via such a transmission gear box. 
     The generator assembly  129  is in particular supported by the intermediate casing  117 ,  118 ,  121 . 
     The first and the second intermediate shaft  127 ,  128  are for example coaxial and each designed to rotate, independently of each other, relative to the casing  117 ,  118 ,  121 , about an intermediate axis  130 . The first or the second intermediate shaft  127 ,  128  thus surrounds the second or the first intermediate shaft  127 ,  128 . In the examples illustrated in  FIGS.  1  to  3   , it is the first intermediate shaft  127  which surrounds the second intermediate shaft  128 . 
     Alternatively, the first and second intermediate shafts  127 ,  128  are arranged parallel relative to each other and in the same plane comprising the longitudinal axis  105 , the first and second intermediate shafts  127 ,  128  further being axially offset relative to each other. According to this variant, each of the first and second intermediate shafts  127 ,  128  is thus designed to rotate relative to the casing  117 ,  118 ,  121 , about an intermediate axis  130  which is specific thereto. 
     The first and the second intermediate shafts  127 ,  128  are for example designed to rotate, in an opposite direction of rotation relative to each other, relative to the casing  117 ,  118 ,  121 , about the intermediate axis  130  Alternatively, the first and the second intermediate shafts  127 ,  128  are designed to rotate, in the same direction of rotation, relative to the casing  117 ,  118 ,  121 , about the intermediate axis  130 . 
     The first and second intermediate shafts  127 ,  128  each extend along the intermediate axis  130  between a first end  127   a ,  128   a  and an opposite second end  127   b ,  128   b.    
     The first end  127   a ,  128   a  of each of the first and second intermediate shafts  127 ,  128  is designed to draw mechanical power from the low pressure shaft  122  or the high pressure shaft  123 . 
     For this, the first end  127   a ,  128   a  of each of the first and second intermediate shafts  127 ,  128  carries for example a first toothed wheel  127   c ,  128   c  which is secured in rotation with the first or the second intermediate shaft  127 ,  128  about the intermediate axis  130 . The first toothed wheel  127   c ,  128   c  of the first and second intermediate shafts  127 ,  128  is further meshed with a toothed wheel  122   a ,  123   a  itself carried by the low pressure shaft  122  or the high pressure shaft  123  and mounted secured in rotation on the low pressure shaft  122  or on the high pressure shaft  123  about the longitudinal axis  105 . 
     The first toothed wheels  127   c ,  128   c  of the first and second intermediate shafts  127 ,  128  as well as the toothed wheels  122   a ,  123   a  of the low and high pressure shafts  122 ,  123  are for example conically toothed. 
     The first end  127   a ,  128   a  of each of the first and second intermediate shafts  127 ,  128  is for example located axially between the toothed wheels  122   a ,  123   a  of the low and high pressure shafts  122 ,  123 . Thus, when the low and high pressure shafts  122 ,  123  rotate in the same direction of rotation, the first and second intermediate shafts  127 ,  128  rotate in an opposite direction of rotation. 
     Alternatively, the first end  127   a ,  128   a  of each of the first and second intermediate shafts  127 ,  128  is located axially only on one side of the toothed wheels  122   a ,  123   a  of the low and high pressure shafts  122 ,  123 . Thus, when the low and high pressure shafts  122 ,  123  rotate in an opposite direction of rotation, the first and second intermediate shafts  127 ,  128  themselves rotate in an opposite direction of rotation. 
     The second ends  127   b ,  128   b  of the first and second intermediate shafts  127 ,  128  are designed to transmit, independently of each other, mechanical power to the generator assembly  129 . 
     The generator assembly  129  is for example housed in one of the arms  121 . In this manner, the generator assembly  129  is cooled by the gas stream, called secondary stream, which circulates in the secondary flow path  106 . 
     The generator assembly  129  is, in particular, housed in the arm  121  located at 6 o&#39;clock. This allows preventing the addition of mass in the arm  121  from disturbing the static equilibrium of the turbine engine  100 A,  1006 ,  100 C, by creating a moment of the force of gravity relative to the longitudinal axis  105 , which would tend to cause the turbine engine  100 A,  1006 ,  100 C to rotate. 
     For this, the first and second intermediate shafts  127 ,  128  extend for example from the core of the turbine engine  100 A,  1006 ,  100 C through the primary flow path  104  and the inter-flow path compartment  107  to the arm  121  which passes through the secondary flow path  106  and in which the generator assembly  129  is housed. Thus, the first end  127   a ,  128   a  of the first and second intermediate shafts  127 ,  128  is located in the core of the turbine engine  100 A,  1006 ,  100 C, while the second end  127   b ,  128   b  thereof is located in the arm  121  which houses the generator assembly  129 . 
     The first and second intermediate shafts  127 ,  128  are for example themselves housed in an arm (not represented) extending from the core of the turbine engine  100 A,  1006 ,  100 C to the hub  118 , in particular to the annular inner wall  120  of the hub  118 . The arm is arranged axially between the low pressure compressor  110  and the high pressure compressor  111 . 
     The generator assembly  129  is, for example, arranged axially downstream of the ancillaries which are also housed in the arm  121 . The arm  121  which houses the generator assembly  129  thus extends axially downstream in the secondary flow path  106 . This area of the secondary flow path  106 , in which the arm  121  extends, is called “bifurcation”. 
     A firewall partition is for example provided between the generator assembly  129  and the inter-flow path compartment  107 , in particular at the outer annular wall  119  of the hub  118 , so as to limit the risk of fire and heat transfers from the arm  121  which houses the generator assembly  129  towards the inter-flow path compartment  107 . 
     According to the first embodiment illustrated in  FIG.  1   , the generator assembly  129  of the turbine engine  100 A comprises a first drive shaft  131 , one or more first alternators  132 , a second drive shaft  133  and one or more second alternators  134 . 
     The first drive shaft  131  is designed to draw mechanical power from the first intermediate shaft  127  and to rotate, relative to the casing  117 ,  118 ,  121 , about a first drive axis  135 . 
     The second drive shaft  133  is designed to draw mechanical power from the second intermediate shaft  128  and to rotate, relative to the casing  117 ,  118 ,  121 , about a second drive axis  136 . 
     The first and second drive shafts  131 ,  133  are coaxial and each designed to rotate, independently of each other and in an opposite direction of rotation, about the first and second drive axes  135 ,  136  which coincide. The first or the second drive shaft  131 ,  133  thus surrounds the second or the first drive shaft  133 ,  131 . The first and second drive shafts  131 ,  133  are concentric. They are further counter-rotating. In the example illustrated in  FIG.  1   , it is the first drive shaft  131  which surrounds the second drive shaft  133 . The generator assembly  129  is thus less bulky for the same electrical power produced. This also allows limiting the master cross-section of the arm  121 , that is to say the maximum section of the arm  121 , taken transversely relative to the longitudinal axis  105 . The performance in the “windmilling” phase is improved when it is the first drive shaft  131  which surrounds the second drive shaft  133 . 
     The first alternator(s)  132  each comprise an inductor rotor mounted secured in rotation with one of the first and second drive shafts  131 ,  133  and an induced rotor mounted secured in rotation with the other of the first and second drive shafts  131 ,  133  and located facing the inductor rotor. The first alternators  132  are for example evenly distributed along the first and second drive shafts  131 ,  133 . 
     In this manner, the relative rotation of the inductor rotor of the or each of the first alternators  132  relative to the induced rotor of said first alternator  132  creates a variation in the electromagnetic flux which induces an alternating electric current in the induced rotor. 
     Moreover, the inductor and induced rotors of the or each of the first alternators  132  being able to rotate in an opposite direction of rotation relative to each other, the generator assembly  129  allows producing more electrical power. 
     The inductor rotor of the or each of the first alternators  132  comprises, for example, at least one permanent magnet or at least one electromagnet formed by a winding which is direct current powered, while the induced rotor of the or each of the first alternators  132  comprises at least one winding. 
     The second alternator(s)  134  each comprise an inductor rotor mounted secured in rotation with that of the first and second drive shafts  131 ,  133  which is surrounded by the other of the first and second drive shafts  131 ,  133 , herein the second drive shaft  133 , and an induced stator which is fixed relative to the casing  117 ,  118 ,  121  and therefore relative to the inductor rotor. The second alternators  134  are for example evenly distributed along the second drive shaft  133 . 
     In this manner, the rotation of the inductor rotor of the or each of the second alternators  134  relative to the fixed induced stator of said second alternator  134  creates a variation in the electromagnetic flux which induces an alternating electric current in the induced stator. 
     The fact of multiplying the first alternators  132  and/or the second alternators  134  also allows minimising the heating of the electric generator  129 , and thus not making the implementation of a cooling system, which is specifically dedicated to the electric generator  129 , mandatory. 
     The inductor rotor of the or each of the second alternators  134  comprises for example at least one permanent magnet. Alternatively, the inductor rotor of the or each of the second alternators  134  comprises at least one electromagnet formed by a winding which is direct current powered. 
     The induced stator of the or each of the second alternators  134  comprises for example at least one winding. 
     The first and second drive shafts  131 ,  133  each extend along the first and second drive axes  135 ,  136 , which coincide, between a first end  131   a ,  133   a  and an opposite second end  131   b ,  133   b.    
     The first and second alternators  132 ,  134  are for example arranged on opposite sides of that of the first and second drive shafts  131 ,  133  which is surrounded by the other of the first and second drive shafts  131 ,  133 , along the first and second drive axes  135 ,  136 . The first alternators  132  are for example arranged on the side of the first end  131   a ,  133   a  of that of the first and second drive shafts  131 ,  133  which is surrounded by the other of the first and second drive shafts  131 ,  133 , while the second alternators  134  are arranged on the side of the second end  131   b ,  133   b  of said first or second drive shaft  131 ,  133 . In  FIG.  1   , the first alternators  132  are arranged on the side of the first end  133   a  of the second drive shaft  133 , while the second alternators  134  are arranged on the side of the second end  133   b  of the second drive shaft  133 . 
     The first end  131   a ,  133   a  of each of the first and second drive shafts  131 ,  133  is designed to draw mechanical power from the first or second intermediate shaft  127 ,  128 . 
     For this, the first end  131   a ,  133   a  of each of the first and second drive shafts  131 ,  133  carries for example a first toothed wheel  131   c ,  133   c  which is secured in rotation with the first or second drive shaft  131 ,  133  about the first or the second drive axis  135 ,  136 . The first toothed wheel  131   c ,  133   c  of the first and second drive shafts  131 ,  133  is further meshed with a second toothed wheel  127   d ,  128   d  itself carried by the second end  127   b ,  128   b  of the first or second intermediate shaft  127 ,  128  and mounted secured in rotation on the first or the second intermediate shaft  127 ,  128  about the intermediate axis  130 . 
     The first toothed wheels  131   c ,  133   c  of the first and second drive shafts  131 ,  133  as well as the second toothed wheels  127   d ,  128   d  of the first and second intermediate shafts  127 ,  128  are for example conically toothed. 
     When the first and second intermediate shafts  127 ,  128  are designed to rotate in the same direction of rotation, an additional pinion is for example provided to transmit mechanical power between the toothed wheels  127   d ,  131   c  of the first intermediate shaft  127  and of the first drive shaft  131  or between the toothed wheels  128   d ,  133   c  of the second intermediate shaft  128  and the second drive shaft  133 , in order to reverse the direction of rotation of the first and second drive shafts  131 ,  133 . 
     The first and second drive axes  135 ,  136 , which coincide, are for example coplanar with the longitudinal axis  105  and/or the intermediate axis  130  of the first and second intermediate shafts  127 ,  128 . This plane which is common to the considered axes may correspond to a plane of symmetry of the bifurcation formed by the arm  121 . It can be vertical or inclined relative to the vertical. 
     The first and second drive axes  135 ,  136  are for example oriented generally axially. They are for example substantially parallel to the longitudinal axis  105 . The axial orientation of the first and second drive axes  135 ,  136  aims at promoting the axial extension of the arm  121  which houses the generator assembly  129  in the bifurcation, rather than an increase in height of the secondary flow path  106 . The term “height” of the secondary flow path  106 , means the radial dimension of the secondary flow path  106 . In other words, the height of the secondary flow path  106  corresponds to the distance, taken radially by relative to the longitudinal axis  105 , between the outer shroud  117  and the outer annular wall  119  of the hub  118 . This further allows limiting the master cross-section of the arm  121 . 
     The first ends  131   a ,  133   a  of the first and second drive shafts  131 ,  133  are for example located upstream, while the second ends  131   b ,  133   b  of the first and second drive shafts  131 ,  133  are located downstream. This allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . 
     The first alternator(s)  132  are for example located upstream, while the second alternator(s)  134  are located downstream. 
     The first alternator(s)  132  and the second alternator(s)  134  can respectively be housed in a first housing  150  and in a second housing  151  which are themselves housed in the arm  121  ( FIG.  4   ). The first housing  150  further has a transverse dimension D 1 , taken in a transverse direction, generally horizontal, perpendicular to the axial dimension of gas flow, greater than that D 2  of the second housing  151 . In this manner, it is possible to take advantage of the aerodynamic profile of the shaft  121  whose section, taken tangentially relative to the longitudinal axis  105 , is wider upstream than downstream in the axial direction of gas flow, by installing first alternators  132  which are larger than the second  134  alternators. 
     The first housing  150  can also be arranged in contact, in particular generally tangential relative to the longitudinal axis  105 , with or even flush with a wall  152  of the arm  121 , so as to improve the cooling of the first alternators  132  by the secondary flow circulating in the secondary flow path  106 . The first housing  150  is for example in contact with the wall  152  via a layer of heat conductive material adapted to prevent a wear by friction of the wall  152  and of the first housing  150  and/or to dampen vibrations, such as a silicone elastomer. The contact areas between the first housing  150  and the wall  152  of the arm  121  are referenced  153  in  FIG.  4   . 
     Alternatively (not represented), the first and second drive axes  135 ,  136  are oriented generally radially relative to the longitudinal axis  105 . The radial orientation of the first and second drive axes  135 ,  136  aims at promoting the increase in height of the secondary flow path  106 , rather than the axial extension of the arm  121  which houses the generator assembly  129  in the bifurcation. This further allows limiting the master cross-section of the arm  121 . 
     The first ends  131   a ,  133   a  of the first and second drive shafts  131 ,  133  are for example located radially inside relative to the longitudinal axis  105 , while the second ends  131   b ,  133   b  of the first and second drive shafts drive  131 ,  133  are located radially outside. This allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . 
     Alternatively (not represented), the first and second drive axes  135 ,  136  are inclined both axially and radially. This allows obtaining a compromise between the axial extension of the arm  121  which houses the generator assembly  129  in the bifurcation and the increase in the height of the secondary flow path  106 . 
     According to the second embodiment illustrated in  FIG.  2   , the generator assembly  129  of the turbine engine  100 B comprises, in addition to the first and second drive shafts  131 ,  133  and the first and second alternators  132 ,  134 , a third drive shaft  137 , one or more third alternators  138 , a fourth drive shaft  139  and one or more fourth alternators  140 . 
     The third drive shaft  137  is designed to draw mechanical power from the first drive shaft  131  and to rotate, relative to the casing  117 ,  118 ,  121 , about a third drive axis  141 . 
     The fourth drive shaft  139  is designed to draw mechanical power from the second drive shaft  133  and to rotate, relative to the casing  117 ,  118 ,  121 , about a fourth drive axis  142 . 
     The third and fourth drive shafts  137 ,  139  are coaxial and each designed to rotate, independently of each other and in an opposite direction of rotation, about the third and fourth drive axes  141 ,  142  which coincide. The third or the fourth drive shaft  137 ,  139  thus surrounds the fourth or the third drive shaft  139 ,  137 . The third and fourth drive shafts  137 ,  139  are concentric. They are also counter-rotating. In the example illustrated in  FIG.  2   , it is the third drive shaft  137  which surrounds the fourth drive shaft  139 . The generator assembly  129  is thus less bulky for the same produced electrical power. This also allows limiting the master cross-section of the arm  121 . The performance in the “windmilling” phase is improved when it is the third drive shaft  137  which surrounds the fourth drive shaft  139 . 
     The third alternator(s)  138  each comprise an inductor rotor mounted secured in rotation with one of the third and fourth drive shafts  137 ,  139  and an induced rotor mounted secured in rotation with the other of the third and fourth drive shafts  137 ,  139  and located facing the inductor rotor. The third alternators  138  are for example evenly distributed along the third and fourth drive shafts  137 ,  139 . 
     In this manner, the relative rotation of the inductor rotor of the or each of the third alternators  138  relative to the induced rotor of said third alternator  138  creates a variation in the electromagnetic flux which induces an alternating electric current in the induced rotor. 
     Moreover, the inductor and induced rotors of the or each of the third alternators  138  being able to rotate in an opposite direction of rotation relative to each other, the generator assembly  129  allows producing even more electrical power. 
     The inductor rotor of the or each of the third alternators  138  comprises for example at least one permanent magnet or at least one electromagnet formed by a winding which is direct current powered, while the induced rotor of the or each of the third alternators  138  comprises at least one winding. 
     The fourth alternator(s)  140  each comprise an inductor rotor mounted secured in rotation with that of the third and fourth drive shafts  137 ,  139  which is surrounded by the other of the third and fourth drive shafts  137 ,  139 , herein the fourth drive shaft  139 , and an induced stator which is fixed relative to the casing  117 ,  118 ,  121  and therefore relative to the inductor rotor. The fourth alternators  140  are for example evenly distributed along the fourth drive shaft  139 . 
     In this manner, the rotation of the inductor rotor of the or each of the fourth alternators  140  relative to the fixed induced stator of said fourth alternator  140  creates a variation in the electromagnetic flux which induces an alternating electric current in the induced stator. 
     The addition of the third and fourth drive shafts  137 ,  139  as well as the third and fourth alternators  138 ,  140  allows increasing the electrical power produced by the generator assembly  129 . 
     The inductor rotor of the or each of the fourth alternators  140  comprises for example at least one permanent magnet. Alternatively, the inductor rotor of the or each of the fourth alternators  138 ,  140  comprises at least one electromagnet formed by a winding which is direct current powered. 
     The induced stator of the or each of the fourth alternators  138 ,  140  comprises for example at least one winding. 
     The third and fourth drive shafts  137 ,  139  each extend along the third or fourth drive axes  141 ,  142 , which coincide, between a first end  137   a ,  139   a  and a second opposite end  137   b ,  139   b.    
     The third and fourth alternators  138 ,  140  are for example arranged on opposite sides of that of the third and fourth drive shafts  137 ,  139  which is surrounded by the other of the third and fourth drive shafts  138 ,  140 , along the third and fourth drive shafts  141 ,  142 . The third alternators  138  are for example arranged on the side of the first end  137   a ,  139   a  of that of the third and fourth drive shafts  137 ,  139  which is surrounded by the other of the third and fourth drive shafts  137 ,  139 , while the fourth alternators  140  are arranged on the side of the second end  137   b ,  139   b  of said third and fourth drive shafts  137 ,  139 . In  FIG.  1   , the third alternators  138  are arranged on the side of the first end  137   a  of the third drive shaft  137 , while the fourth alternators  140  are arranged on the side of the second end  139   b  of the fourth drive shaft  139 . 
     The first end  137   a ,  139   a  of each of the third and fourth drive shafts  137 ,  139  is designed to draw mechanical power from the first or second drive shaft  131 ,  133 . 
     For this, the first end  137   a ,  139   a  of each of the third and fourth drive shafts  137 ,  139  carries for example a first toothed wheel  137   c ,  139   c  which is secured in rotation with the third or the fourth drive shaft  137 ,  139  about the third or fourth drive axis  141 ,  142 . The first toothed wheel  137   c ,  139   c  of the third and fourth drive shafts  137 ,  139  is further meshed with the first toothed wheel  131   c ,  133   c  of the first or second shaft  131 ,  133 , or with a second toothed wheel  133   d  itself carried by the first or second drive shaft  131 ,  133  and mounted secured in rotation on the first or second drive shaft  131 ,  133  about the first or second drive axis  135 ,  136 . 
     In the example illustrated in  FIG.  2   , the first toothed wheel  137   c  of the third drive shaft  137  is meshed with the first toothed wheel  131   c  of the first drive shaft  131 , while the first toothed wheel  139   c  of the fourth drive shaft  139  is meshed with a second toothed wheel  133   d  of the second drive shaft  133 . 
     Where appropriate, the first toothed wheel(s)  137   c ,  139   c  of the third and fourth drive shafts  137 ,  139  which are engaged with the first toothed wheel(s)  131   c ,  133   c  of the first or second drive shaft  131 ,  133 , are conically toothed. 
     Where appropriate, the second toothed wheel(s)  133   d  of the first or second drive shaft  131 ,  133  are for example straight-toothed. The first toothed wheel(s)  137   c ,  139   c  of the first and second drive shafts  131 ,  133  which are engaged with the second toothed wheel(s)  133   d  of the first or second drive shaft  131 ,  133 , are themselves straight-toothed. 
     The longitudinal axis  105  and the first, second, third and fourth drive axes  135 ,  136 ,  141 ,  142  are for example comprised in the same plane. This allows, for example, taking advantage of the entire height of the secondary flow path  106 , without increasing the master cross-section of the arm  121 . 
     The first, second, third and fourth drive axes  135 ,  136 ,  141 ,  142 , which are parallel to each other in the example of  FIG.  2   , are for example coplanar with the longitudinal axis  105  and/or the intermediate axis  130  of the first and second intermediate shafts  127 ,  128 . 
     The third and fourth drive axes  141 ,  142  are for example respectively parallel to the first and second drive axes  135 ,  136 . 
     The third and fourth drive axes  141 ,  142  are for example oriented generally axially. They are substantially parallel to the longitudinal axis  105 . 
     The first ends  137   a ,  139   a  of the third and fourth drive shafts  137 ,  139  are for example located upstream, while the second ends  137   b ,  139   b  of the third and fourth drive shafts  137 ,  139  are located downstream. This allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . The third alternator(s)  138  are for example located upstream, while the fourth alternator(s)  140  are located downstream. 
     The third alternator(s)  138  and the fourth alternator(s)  140  can respectively be housed in the first housing  150  or a third housing itself housed in the arm  121  and in the second housing  151  or a fourth housing itself housed in the arm  121 . 
     Where appropriate, the third housing has a transverse dimension, taken in a transverse direction, generally horizontal, perpendicular to the axial dimension of gas flow, which is greater than that of the fourth housing. In this manner, it is possible to take advantage of the aerodynamic profile of the shaft  121  whose section, taken tangentially relative to the longitudinal axis  105 , is wider upstream than downstream in the axial direction of gas flow, by installing third alternators  138  which are larger than the fourth alternators  140 . 
     Where appropriate, the third housing is in contact, in particular generally tangential relative to the longitudinal axis  105 , with or even flush with the wall  152  of the arm  121 , so as to improve the cooling of the third alternators  138  by the secondary flow circulating in the secondary flow path  106 . The third housing is for example in contact with the wall  152  via a layer of layer of heat conductive material adapted to prevent wear by friction of the wall  152  and of the third casing and/or to dampen the vibrations, such as a silicone elastomer. 
     The third and fourth drive shafts  137 ,  139  are for example located radially outside relative to the longitudinal axis  105 , while the first and second drive shafts  131 ,  133  are located radially inside. This also allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . 
     Alternatively (not represented), the first and second drive axes  135 ,  136  are oriented generally radially relative to the longitudinal axis  105 . 
     The first ends  137   a ,  139   a  of the third and fourth drive shafts  137 ,  139  are for example located radially inside relative to the longitudinal axis  105 , while the second ends  137   b ,  139   b  of the third and fourth drive shafts  137 ,  139  are located radially outside. This allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . 
     The third and fourth drive shafts  137 ,  139  are for example located downstream, while the first and second drive shafts  131 ,  133  are located upstream. This also allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . 
     Alternatively (not represented), the third and fourth drive axes  135 ,  136  are inclined both axially and radially. This allows obtaining a compromise between the axial extension of the arm  121  which houses the generator assembly  129  in the bifurcation and the increase in the height of the secondary flow path  106 . 
     Thus, according to this second embodiment, the first and second drive shafts  131 ,  133  form a first pair of drive shafts, while the third and fourth drive shafts  137 ,  139  form a second pair of drive shafts. Of course, one or more pairs of additional drive shafts can be provided, such as a third pair of drive shafts (not represented) drawing mechanical power from the second pair of drive shafts  137 ,  139  in the same manner as the second pair of drive shafts  137 ,  139  draws mechanical power from the first pair of drive shafts  131 ,  133 , or even a fourth pair of drive shafts (not represented) drawing mechanical power from the third pair of drive shafts in the same manner as the third pair of drive shafts draws mechanical power from the second pair of drive shafts  137 ,  139 , etc. The description above therefore remains applicable to these pairs of additional drive shafts. 
     According to the third embodiment illustrated in  FIG.  3   , the generator assembly  129  of the turbine engine  100 C comprises an inner drive shaft  143  designed to rotate relative to the casing  117 ,  118 ,  121  about a drive axis  144 , an outer drive shaft  145  designed to rotate relative to the casing  117 ,  118 ,  121  around the inner drive shaft  143  in an opposite direction of rotation, as well as one or more alternators  146 . The inner and outer drive shafts  143 ,  145  are concentric. They are further counter-rotating. 
     The inner drive shaft  143  is further designed to draw mechanical power from the first intermediate shaft  127  or from the second intermediate shaft  128 , while the outer drive shaft  145  is designed to draw mechanical power from the second intermediate shaft  128  or from the first intermediate shaft  127 . In the example illustrated in  FIG.  3   , the inner drive shaft  143  draws mechanical power from the first intermediate shaft  127 , while the outer shaft drive  145  draws mechanical power from the second intermediate shaft  128 . 
     The alternator(s)  146  each comprise an inner body  146   a , inductor or induced, mounted secured in rotation with the inner drive shaft  143  and an outer body  146   b , induced or inductor, mounted secured in rotation with the outer drive shaft  145  and located facing the inner body  146   a . The alternators  146  are for example evenly distributed along the inner and outer drive shafts  143 ,  145 . 
     In this manner, the relative rotation of the inner body  146   a  of each of the alternators  146  relative to the outer body  146   b  of said alternator  146  creates a variation in the electromagnetic flux which induces an alternating electric current in the inner body  146   a  or in the outer body  146   b.    
     Furthermore, the inner body  146   a  and the outer body  146   b  of each of the alternators  146  being able to rotate in an opposite direction of rotation relative to each other, the generator assembly  129  allows producing more electrical power. 
     The inner body  146   a  of the alternators  146  comprises for example at least one permanent magnet or at least one electromagnet formed by a winding which is direct current powered, while the outer body  146   b  of the alternators  146  comprises at least one winding. 
     Alternatively (not represented), the outer body  146   b  of the alternators  146  comprises for example at least one winding, while the outer body  146   b  of the alternators  146  comprises at least one permanent magnet or at least one electromagnet formed by a winding which is direct current powered. The inner and outer drive shafts  143 ,  145  each extend along the drive axis  144  between a first end  143   a ,  145   a  and an opposite second end  143   b ,  145   b.    
     The first end  143   a ,  145   a  of each of the inner and outer drive shafts  143 ,  145  is designed to draw mechanical power from the first or the second intermediate shaft  127 ,  128 . 
     For this, the first end  143   a ,  145   a  of each of the inner and outer drive shafts  143 ,  145  carries for example a toothed wheel  143   c ,  145   c  which is secured in rotation with the inner or outer drive shaft  143 ,  145  about the drive axis  144 . The toothed wheel  143   c ,  145   c  of the inner and outer drive shafts  143 ,  145  is further meshed with the second toothed wheel  127   d ,  128   d  of the first or second intermediate shaft  127 ,  128 . 
     The toothed wheels  143   c ,  145   c  of the inner and outer drive shafts  143 ,  145  as well as the second toothed wheels  127   d ,  128   d  of the first and second intermediate shafts  127 ,  128  are for example conically toothed. 
     When the first and second intermediate shafts  127 ,  128  are designed to rotate in the same direction of rotation, an additional pinion is for example provided to transmit mechanical power between the toothed wheels  127   d ,  143   c  of the first intermediate shaft  127  and that of the inner and outer drive shafts  143 ,  145  which it drives or between the toothed wheels  128   d ,  145   c  of the second intermediate shaft  128  and that of the inner and outer drive shafts  143 ,  145  which it drives, in order to reverse the direction of rotation of the inner and outer drive shafts  143 ,  145 . 
     The drive axis  144  is for example coplanar with the longitudinal axis  105  and/or the intermediate axis  130  of the first and second intermediate shafts  127 ,  128 . 
     The drive axis  144  is for example oriented generally radially relative to the longitudinal axis  105 . The radial orientation of the drive axis  144  aims at promoting the increase in height of the secondary flow path  106 , rather than the axial extension of the arm  121  which houses the generator assembly  129  in the bifurcation. This further allows limiting the master cross-section of the arm  121 . 
     The first ends  143   a ,  145   a  of the inner and outer drive shafts  143 ,  145  are for example located radially inside relative to the longitudinal axis  105 , while the second ends  143   b ,  145   b  of the inner and outer drive shafts  143 ,  145  are located radially outside. This allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . 
     Alternatively (not represented), the drive axis  144  is oriented generally axially. It is substantially parallel to the longitudinal axis  105 . The axial orientation of the drive axis  144  aims at promoting the axial extension of the arm  121  which houses the generator assembly  129  in the bifurcation, rather than an increase in height of the secondary flow path  106 . 
     The first ends  143   a ,  145   a  of the inner and outer drive shafts  143 ,  145  are for example located upstream, while the second ends  143   b ,  145   b  of the inner and outer drive shafts  143 ,  145  are located downstream. This allows limiting the dimensions of the first and second intermediate shafts  127 ,  128  along the intermediate axis  130 . 
     Alternatively (not represented), the drive axis  144  is inclined both axially and radially. This allows obtaining a compromise between the axial extension of the arm  121  which houses the generator assembly  129  in the bifurcation and the increase in the height of the secondary flow path  106 . 
     Thus, according to this third embodiment, the inner and outer drive shafts  143 ,  145  form a pair of drive shafts. Of course, one or several pairs of additional drive shafts may be provided, such as a second pair of drive shafts (not represented) drawing mechanical power from the first pair of drive shafts formed by the inner and outer drive shafts  143 ,  145  in the same manner as the first pair of drive shafts  143 ,  145  draws mechanical power from the first and second intermediate shafts  127 ,  128  or even a third pair of drive shafts (not represented) drawing mechanical power from the second pair of drive shafts in the same manner as the second pair of drive shafts draws mechanical power from the first pair of drive shafts  143 ,  145 , etc. The description above therefore remains applicable to these pairs of additional drive shafts. The longitudinal axis  105  and the drive axes  144  of these pairs of drive shafts  143 ,  145  are for example comprised in the same plane. 
     Intermediate pinions  147 ,  148  can further be provided to draw mechanical power from the first and second intermediate shafts  127 ,  128  and to transmit this mechanical power to the first toothed wheel  131   c ,  133   c  of the first and second drive shafts  131 ,  133  or to the toothed wheel  143   c ,  145   c  of the inner and outer drive shafts  143 ,  145 . Intermediate pinions  147 ,  148  are for example illustrated in  FIG.  3   . 
     In the case of an additional pinion reversing the direction of rotation of the inner and outer drive shafts  143 ,  145 , this additional pinion is added to the intermediate pinions  147 ,  148 , transmitting mechanical power either from one of the first and second intermediate shafts  127 ,  128  to one of the intermediate pinions  147 ,  148 , or from one of the intermediate pinions  147 ,  148  to one of the inner and outer drive shafts  143 ,  145 . 
     The turbine engine  100 A,  1006 ,  100 C may further comprise a regulation system  149  via which the generator assembly  129  delivers electrical energy to the accessory or accessories  125 ,  126 . 
     The regulation system  149  is in particular designed to receive the alternating electric currents produced by the first and second alternators  132 ,  134 , and/or by the third and fourth alternators  138 ,  140  or by the alternators  146  and to deliver, from these alternating electric currents, an electric current capable of operating the accessory or accessories  125 ,  126 . 
     The regulation system  149  is for example provided with an electrical energy storage device (not represented) designed to store the excess electrical energy produced by the generator assembly  129  and to deliver the stored electrical energy to the accessory or accessories  125 ,  126 , when the electrical energy produced by the generator assembly  129  is not sufficient to power the accessory or accessories  125 ,  126 .