Double-flow turbojet engine assembly with epicycloidal or planetary reduction gear

Twin-spool turbojet engine including a central shaft (AC) surrounded by a high-pressure spool (CH) that are coaxial and independent with respect to rotation, this turbojet engine including, from upstream (AM) to downstream (AV) considered in the direction of travel of the flow that passes through it when it is in service:

• a fan (13) driven by the central shaft (AC);
• a high-pressure compressor (16) and a high-pressure turbine (17) forming part of the high-pressure spool (CH);
• an interturbine casing (18);
• a low-pressure turbine (19);
• an exhaust casing (21);
• this turbojet engine further including:
• a low-pressure rotor (RB) extending downstream of the central shaft (AC) and which comprises the low-pressure turbine (19);
• a rotor bearing (23) carried by the exhaust casing (21), and which rotationally guides the low-pressure rotor (RB);
• a reduction gear (22, 22′) by means of which the low-pressure rotor (RB) drives the central shaft (AC), this reduction gear being located upstream of the rotor bearing (23);
• a downstream shaft bearing (29) that rotationally guides the central shaft (AC) while being located upstream of the reduction gear (22, 22′).