An adjusting device having at least one tappet assembly. The at least one tappet assembly comprises a tappet, at least one guide cylinder, and a pole core. The tappet is arranged in the guide cylinder in a movable manner along a longitudinal axis, and a non-magnetic connection socket is arranged between the guide cylinder and the pole core. The guide cylinder and the pole core are arranged at a distance to each other in the longitudinal axis by the connection socket.