Main shaft assembly for central transmission test of aero-engine and assembling method

The invention provides a main shaft assembly for a central transmission test of an aero-engine, and the main shaft assembly comprises a main shaft which is provided with two first flanges, a loading sliding bearing is installed between the two first flanges, a loading disc is installed on the outer side of the loading sliding bearing, and a plurality of loaders are installed on the loading disc; a plurality of loaders are applied to the loading disc to push the loading sliding bearing to move, so that the loading of the axial force and the radial force of the main shaft is realized; the taper sleeve is provided with an inner hole conical surface matched with the spindle head conical surface of the spindle, and the central transmission is installed on the taper sleeve and locked through a locking nut installed on the taper sleeve to form a central transmission-taper sleeve assembly; the spacer sleeve is arranged between the second flange of the main shaft and the taper sleeve; the end face pressing plate is in