Steering column device

1. A steering column device comprising:

a bracket including a fixed portion to be fixed to a vehicle body and a first wall extending downward from the fixed portion;

a steering shaft having an upper end in an axial direction of the steering shaft for fixing a steering wheel;

a steering column including one end supported by the vehicle body and an outer peripheral surface with a second wall, and configured to rotatably support the steering shaft inside the steering column;

a clamp shaft penetrating the first wall, the clamp shaft being configured to switch between a pressure contact state where the first wall and the second wall are in pressure contact with each other and a non-pressure contact state where the first wall and the second wall are not in pressure contact with each other;

two first protrusions disposed on one of the first wall or the second wall separately in a first direction parallel to an axial direction of the steering column and extending in a second direction perpendicular to the axial direction of the steering column, the two first protrusions being disposed with the clamp shaft between the two first protrusions; and

two second protrusions disposed on the other one of the first wall or the second wall separately in the second direction and extending in the first direction,

wherein each of the two first protrusions contacts both of the two second protrusions in the pressure contact state.

2. The steering column device according to claim 1 , wherein

the first, wall has a first elongated hole formed between the two first protrusions along a direction of tilt movement of the steering shaft,

part of the clamp shaft is located in the first elongated hole, and

the clamp shaft is adapted to move inside the first elongated hole in the non-pressure contact state.

3. The steering column device according to claim 2 , wherein

the steering column comprises:

an upper jacket configured to rotatably support the steering shaft inside a cylindrical inner portion of the upper jacket and including a second elongated hole formed along a direction of telescopic movement of the steering shaft in a region opposed to the first elongated hole; and

a lower jacket configured to slidably support the upper jacket in the direction of telescopic movement of the steering shaft and to rotatably support the steering shaft together with the upper jacket,

part of the clamp shaft is located in the second elongated hole, the clamp shaft is configured to penetrate the first wall and the second wall, adapted to move inside the second elongated hole in the non-pressure contact state, and configured to bring the first wall, the second wall, and the upper jacket into pressure contact with one another in the pressure contact state.

4. The steering column device according to claim 1 ,

wherein the two first protrusions and the two second protrusions are in contact with each other at four contact portions in the pressure contact state, and

wherein two contact portions out of the four contact portions are located on a line parallel to an axial center line of the steering column while passing through an axial center of the clamp shaft.

5. The steering column device according to claim 1 ,

wherein the two first protrusions and the two second protrusions are in contact with each other at four contact portions in the pressure contact state, and

wherein the clamp shaft is located at a center of the four contact portions.