Blocking device for a closure element or a switching element

A locking device with a locking device housing and a barrier device, wherein the barrier device comprises a stator, a rotor with a rotor axis, and an electromechanical actuator in the rotor, wherein the rotor has a first rotor element and a second rotor element, wherein the first rotor element and the second rotor element are arranged axially one behind the other in relation to the rotor axis, the first rotor element and the second rotor element are connected to each other in a rotationally fixed manner, wherein the electromechanical actuator is arranged in one of the rotor elements, wherein the barrier device comprises a barrier element, wherein in a first position the barrier element prevents the rotor from being rotatable with respect to the stator, wherein in a second position the barrier element enables the rotor to be rotatable with respect to the stator, wherein the barrier element is moved between the first and the second position,

• wherein the barrier device is received in the locking device housing, wherein the locking device comprises a fastening element, wherein the fastening element is introduced from the outside into the locking device housing in order to fasten the stator to the locking device housing in a rotationally fixed manner,
• wherein the locking device is designed as a locking cylinder, a knob cylinder, a furniture cylinder, or a padlock.