Device for locking, in any one of the notches of a rack, an adjusting finger and armchair employing said device

In a device for locking, in any one of the notches of a rack belonging to one of the two mobile elements of a system, an adjusting finger belonging to the second mobile element,

• the first mobile element defines windows for the passage of retractable stops capable of being placed opposite the notches in order to stop the finger and prevent it from joining another notch, these stops being located at the free ends of flexible arms inclined in herringbone fashion and integral at their other ends with a sliding element guided in translation relatively to said first element and said stops being shaped as cams provided to provoke, by cooperating with an edge of the windows, the elastic bending of the arms during the controlled translation of the sliding element and thus the retraction of the stops, the elastic return of the arms provoking translation in the opposite direction of said stops which rest on another edge of said windows to stop the finger.