Patent attributes
A release lever includes: a release pressing portion pressing a portion around a lock portion of a plate spring to release an engagement of the lock portion with a locked portion; an operation portion located in a front side of the release lever and operated by a lock release operation of an operation handle; and a swing fulcrum portion provided between the release pressing portion and the operation portion. The plate spring integrally includes: a base including the swing fulcrum portion and fixed to an upper rail; a rear biasing portion located behind the base in a vehicle front-rear direction and biasing the lock portion in a lock direction; and a front biasing portion located in front of the base in the vehicle front-rear direction and biasing the operation handle upward. The front biasing portion has a biasing force smaller than that of the rear biasing portion.