The invention relates to a drive mechanism (9) for a needle insertion arrangement (1), the drive mechanism (9) including:—a cross beam (16) linearly movable in a distal direction (D) and a proximal direction (P) for moving an injection needle (2),—an actuator (5),—a slider (12) coupled to the actuator (5) and linearly movable in a transversal direction (T) at right angles relative the distal direction D and the proximal direction D,—a cam (14) on one of the cross beam (16) and the slider (12),—a guide track (13) in the other one of the cross beam (16) and the slider (12) adapted to engage the cam (14), the guide track including a sloped section (13.3) such that the cross beam (16) is moved on movement of the slider (12).