Motor vehicle antitheft system comprising improved latch bolt retaining means

A motor vehicle antitheft system of the type comprising an antitheft mechanism comprising a housing in which a manual control member for manually controlling the starting of the vehicle engine and the locking of the vehicle steering column:

• is mounted so that it can move axially between a pulled back locked position in which it locks the steering column and a pushed forward position in which it unlocks the steering column;
• is mounted so that it can rotate between at least one angular position of rest and one angular position of use in which it cannot be pulled axially back;
• and is connected in terms of rotation to a rotary output member forming a cam which is capable of collaborating with a latch bolt to control the movements of the latter which is mounted to slide in the housing in a direction which is radial overall with respect to the axis of rotation of the manual control member between a deployed radially outward antitheft position toward which it is elastically urged and in which it projects through an opening of the housing to immobilize in terms of rotation a member of the steering column when the manual control member is in the angular position of rest and in the pulled back locked position, and a pushed-in position retracted inside the housing when the manual control member is in the pushed forward position, and of the type in which:
• the latch bolt is held radially in the pulled-in retracted position by a latch bolt retaining member for retaining the latch bolt which is mounted to move between an effaced or retracted position and an active position of retaining the latch bolt, toward which position it is elastically urged and in which a retaining finger belonging to the latch bolt retaining member is accommodated in a complimentary notch in the latch bolt,
• said system further comprising elastically deformable means for axially indexing the manual control member in its pulled back locked position and for retaining the manual control member in said pulled back locked position against a return force exerted on the latch bolt retaining member by a return spring;
• wherein the member for retaining the latch bolt is mounted to slide in the housing parallel to the axis of displacement and of rotation of the manual control member, and wherein the finger for retaining the latch bolt is formed at the front free end of the latch bolt retaining member;
• and wherein the displacement of the latch bolt retaining member toward its effaced rear axial position against said return spring is controlled by the backward axial displacement of the manual control member into its pulled back locked position.