A lock device includes a base, a first rotation member, a second rotation member, a first elastic member, and a second elastic member. Protrusions are provided on one of the base and one of the first rotation member and the second rotation member. The protrusions are protruded in a direction parallel to the rotation axis of the first rotation member. An end of one of the first elastic member and the second elastic member is fixed to the protrusions. The protruding length in the rotation axis direction of the protrusions is longer than the length in the rotation axis direction of one of the first elastic member and the second elastic member.