PURPOSE: To provide proper press-fitting when pressing a press-in shaft with the protruded portion of weak mechanical strength through a thrust head and improve the quality of products by thrusting the poor strength protruded portion of the press-in shaft with the help of energizing force only from a housing and then putting a thrusting member in contact with the press-in shaft to apply press-in force in phase for real press-in operation.

CONSTITUTION: A housing 34 which has the end equipped with a clamping means 32 and which is guided and supported by a guide shaft 22 fixed to a support shaft 46 is elastically energized downward and locked to a holder 20 fixed to an up-and-down movable moving member 16 via the support shaft 46, a thrusting member 24 is inserted into the guide shaft 22 in such a manner that it is opposed to a press-in shaft 30 attracted to the clamping means 32 in a coaxial relationship at a preset space, the housing 34 is moved a preset pitch to weakly press the press-in shaft, and then the thrusting member 24 is put in contact therewith for real press-in operation to perform proper press- fitting.