Locking device

The invention discloses a locking device. The locking device comprises a positioning mechanism, a gear, a rack, a connecting rod and a lock seat; the positioning mechanism comprises at least two joint structures, the gear is provided with a matching structure, and the gear can rotate between a first position and a second position; the matching structure located at the first position abuts against one of the at least two joint structures, and the matching structure located at the second position abuts against one of the at least two joint structures; and the connecting rod is provided with a lock, the gear drives the lock to move between a locking position and an unlocking position, the gear located at the first position positions the lock at the locking position, the gear located at the second position positions the lock at the unlocking position, the lock located at the locking position is connected with the lock seat, and the lock located at the unlocking position is separated from the lock seat. According