Modular engine, such as a jet engine, with a speed reduction gear

An engine having a modular structure, comprising a plurality of coaxial modules having, at one end of said engine, a first module comprising a power transmission shaft being driven via a speed reduction gear by a turbine shaft secured to one of said coaxial modules which is separate from the first module of said engine,

• the first module comprising a low-pressure compressor rotor with a low-pressure compressor shaft having a journal,
• the speed reduction gear comprising a drive means having an intermediate shaft driven by the turbine shaft through the journal,
• wherein the engine comprises a first nut for fastening the intermediate shaft to the journal and a second nut for fastening the journal to the turbine shaft,
• said first nut being screwed onto an upstream end portion of the journal, and the first nut being in axial abutment against a shoulder of the intermediate shaft,
• the journal having an upstream portion carrying the intermediate shaft, said intermediate shaft being situated radially between the journal and a rotating ring of a thrust bearing,
• and wherein the intermediate shaft is rigidly connected to the rotating ring.