Pressing and driving mechanism and electric screwdriver containing the same

A pressing and driving mechanism, adapted for use in an electric screwdriver, includes a housing, an output member connected to the housing and movable relative to the housing with user intervention, a first adjustment member connected to the output member and moving along with the latter, and a second adjustment member fixed relative to the housing. The second adjustment member is adapted to be in mechanical contact with the first adjustment member. The first adjustment member moves relative to the second adjustment member when the output member moves relative to the housing, whereby the pressing and driving mechanism actively or passively outputs a continuously changing signal. The present invention can realize the function of automatically changing the output torque/speed with the pressing depth when the electric screwdriver is pressed by the user toward the wall or other workpiece.