Locking device for walk-in seat of vehicle

A locking device for a walk-in seat of a vehicle, the locking device comprising:

• a drive plate having one end hinged to a connection frame interconnecting a seatback frame with a seat cushion frame and having another end hinged to a side frame fixedly mounted to a seat rail, the drive plate formed with a sector gear at a front surface thereof, and having formed therein a slot disposed behind the sector gear;
• a pawl having an upper end hinged to the connection frame and having a lower rear surface formed with a locking gear meshing with the sector gear;
• a buckle hinge pin provided at a lower end of a buckle for a seat belt and having one end passing both through one end of a buckle bracket, the buckle bracket hinged to the connection frame, and through the connection frame so as to be inserted into the slot;
• and
• a slot extension hole extending from a lower end of the slot towards the sector gear and into which the buckle hinge pin enters to be positioned therein when a load is applied to the buckle.