Device for the vertical and automatic wedging of a vehicle seat

A device for wedging vertically in C-shaped sideways, an adjustable removable seat in which the seat-part structure is secured to an underframe formed of two subassemblies, namely a right-hand one and a left-hand one, each comprising a rigid sideplate the lower part of which is shaped into a runner able to run in a C-shaped slideway, each subassembly comprising catches collaborating with returns, teeth or notches of the slideway, and retaining hooks able to collaborate with the internal returns of the slideway when the seat is subjected to impact energy, which device comprises, in each subassembly:

• a vertical journal mounted to rotate in a bearing of the underframe,
• a member for wedging in terms of vertical translation, connected in terms of rotation to the lower end of the journal and having, when viewed from above, a rectangular overall shape the shortest dimension of which is less than the width of the groove of the C-shaped slideway and the longest dimension of which is greater than this width, so as to be able, in the wedged position, to sit under the internal returns of the slideway,
• a spring constantly returning the wedging member to its wedging position,
• a means for causing the journal to pivot against the action of its return spring into a position in which the wedging member can be engaged in the groove of the corresponding slideway,
• and at least one helical ramp which, rotating as one with the journal, collaborates with a fixed complementary bearing surface to move the wedging member vertically and bring it into contact with the returns of the slideway.