Patent ID: 8820485

Claim:
Locking system for a lift door, comprising: a locking device which in an unlocked state enables opening of the lift door, and in a locked state, which prevents opening of the lift door; a reference element; a counter element which is provided for the purpose of entering into interaction with the reference element when at least a condition is fulfilled that the lift car is located in a permissible position relative to a shaft door; a sensor which outputs an electrical signal when the reference element and the counter element have entered into interaction, and wherein the reference element, the counter element and the sensor are arranged in a coupling device for coupling the car door to the shaft door; a control device which transfers the locking device from the locked state into the unlocked state as a function of the electrical signal; wherein the coupling device has a driver skid configured to be moved for coupling purposes against the reference element arranged on the shaft door, and comprises the counter element; and wherein the driver skid comprises a support skid, and the counter element is configured to be moved linearly relative to the support skid by the reference element, the sensor outputting the signal when a spacing between the support skid and the counter element, or a force acting between a contact surface of the support skid and the counter element is detected, which lies in a prescribed range.