Elektromekanisk sylinderlås

An electromechanical cylinder lock-key combination comprises a housing having a bore, a core (10) rotatably arranged in the bore and having a key-way (12). A side bar (20) is arranged to block rotation of the core with respect to the housing when in a blocking position. An electronically controllable actuator (30) is provided to prevent movement of the side bar from the blocking position when a key is not present in the lock. A returning means (50) is arranged to mechanically co-operate with the key and the actuator to move said actuator to a blocking position in response to withdrawal of the key from said key-way. This mechanical movement of the actuator ensures that the electronic blocking mechanism is moved to a blocking position in case of power failure.