Patent ID: 6851331

Claim:
A tilt steering apparatus for a tilt adjustable steering column, comprising: a fixed bracket fixed to a body of a vehicle, and having side plates; a tilt bracket fixed to the steering column and having side plates positioned to slide along the side plates of the fixed bracket at a time of tilt adjustment; a supporting shaft passing through respective insertion holes of the side plates of the fixed bracket and of the side plates of the tilt bracket; a lock lever rotatable around an axis of said supporting shaft and in a locking direction to lock the steering column in an adjusted tilt position, and being rotatable around the axis of said supporting shaft and in a locking releasing direction; and a cam surface and a cam follower which are relatively rotated to cause an edge of the cam follower to be brought into sliding, and non-rolling contact with the cam surface as the lock lever is rotated, the cam surface including a locking position in which the steering column is locked in the adjusted tilt position, a releasing position in which the steering column is unlocked so as to be free to be adjusted to a desired tilt position, and an intermediate position disposed between the locking position and the releasing position, the intermediate position including a plurality of slopes including at least two linear and adjacent slopes corresponding to a rotation stroke position of the lock lever, the at least two slopes sloping upward in a same direction and being connected together at a protruding portion that projects toward the cam follower, the cam surface pressing the edge of the cam follower as the lock lever is rotated in the locking direction so that the side plates of the fixed bracket and the side plates of the tilt bracket are pressed against each other, resulting in the steering column being locked at the adjusted tilt position, wherein the cam follower is moved in a first direction relative to the cam surface when the lock lever is rotated in the locking direction, the at least two slopes slope upward in the first direction, a second one of the two slopes being gentler than a first one of the two slopes, and the cam follower slides from the first slope of the cam surface to the second slope thereof when the lock lever is rotated in the locking direction.