The invention relates to a disengaging member (1) for releasing a link between a motor means (2) and a shaft (3) rotated by said motor means (2), comprising first and second elements (4 and 5) capable of fitting together in a direction substantially parallel to the shaft (3), one being capable of being connected to the motor means (2) by a link that enables same to be rotated by the motor means (2), and the other element being capable of being attached to the shaft (3), characterised in that: the first element (4) comprises at least one recess (6) at the fitting interface (7) between the two elements; the second element (5) comprises at least one resilient means (9) exerting a radial force on the fitting interface (7) via an insertion member (10) capable of being inserted into the recess (6), keeping the two elements secured to one another for rotation therewith up until a predefined transmission torque between the insertion member (10) and the first element (4); the resilient means (9), the recess (6) and the insertion member (10) being configured so that, beyond said predefined torque, the insertion member (10) compresses the resilient means (9) and exits the recess (6).