Method for manufacturing the rotor assembly of a rotating vacuum pump

摘要

A method of manufacturing a rotor assembly (1) for a rotary vacuum pump comprises the steps of: providing a first material; forming a rotor (3) having a male axial projection (9) from said first material; providing a second material; forming, from said second material, a supporting shaft (11) having an end portion (13) provided with a female cavity (15) whose shape and size are such that the cavity can receive said male projection (9) of the rotor (3) with interference at ambient temperature; heating said end portion (13) in order to obtain an expansion of the female cavity (15) sufficient to enable the introduction of the projection (9); introducing said male projection (9) into said female cavity (15); bringing said end portion (13) back to ambient temperature, thereby obtaining the contraction of the size of the cavity (15) and forming therefore a fixed interference coupling between said shaft (11) and said rotor (3).