Lock with preferably automatic latching and its use especially for a removable vehicle seat

An arrangement of a lock in a seat for a motor vehicle provided with a floor,

• the seat comprising a subframe having first and second parts (91, 92) joined together by an articulation (93), the first part forming a sole-plate and the second part (92) forming a leg, the second part (92) being able to move, relative to the first part (91), between an opened-out position and a folded position,
• the lock comprising a catch bolt (20) having a locking body (21) forming a broach intended to be latched in an opening (111) formed in a striker plate (10), the locking body (21) being supported by the first part (91) and the striker plate (10) being fixed to the floor,
• the arrangement comprising a safety device allowing the latching or the release of the locking body (21) only when the second part (92) is in the open-out position, wherein the locking body (21) comprises a cylindrical guide cavity (210), an open extremity (211) and at least one channel (212) transpiercing the locking body (21) in order to come out into the cavity (210),
• wherein the catch bolt (20) comprises further at least one ball (22) housed in the channel (212) and movable between a first projecting position so as to be in contact with the striker plate in order to lock the catch bolt (20) and a second retracted position so as to unlock the catch bolt (20), a needle (23) housed in the cavity (210) and movable be means of a control device (30) between an inactive position and an active position in order to cause the ball (22) to pass from one of its positions to the other,
• and wherein, the safety device (60) comprises two interacting elements (61, 62), a first one (62) carried by the second part (92) and a second one (61) carried by the needle (23).