Steering system

Patent metadata

Field	Value
Publication number	US-9428215-B1
Application number	US-201615081455-A
Country	US
Kind code	B1
Filing date	Mar 25, 2016
Priority date	Mar 31, 2015
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

A steering system includes a second tooth defining member and an energy absorbing unit. The energy absorbing unit includes energy absorbing portions each including a first portion extending upward in a column axial direction from a restraining portion restrained in the column axial direction and a second portion formed by folding back the energy absorbing portion at a fold-back portion, the energy absorbing portions being separated from each other in a first orthogonal direction, and a coupling portion that couples the second portions together and moves together with the second tooth defining member at the time of the secondary collision. At the time of the secondary collision, the energy absorbing portions allow the fold-back portions to move downward in the column axial direction to absorb impact energy while guiding downward movement of the second tooth defining member in the column axial direction between facing edges of the energy absorbing portions.

First claim

What is claimed is:

1. A steering system comprising:
a steering shaft that is configured to contract and extend in a column axial direction;
a column jacket that includes a lower jacket and an upper jacket fitted to the lower jacket and that supports the steering shaft so that the steering shaft is rotatable, the column jacket being configured to contract and extend in the column axial direction;
a first tooth defining member having a plurality of first teeth such that the first teeth are arranged in the column axial direction, the first tooth defining member moving together with the upper jacket;
a support shaft that is supported by the lower jacket or a member supported by the lower jacket and that extends in an orthogonal direction orthogonal to the column axial direction;
a second tooth defining member that has second teeth configured to come into meshing engagement with the first teeth, that is supported by the support shaft so as to be rotatable around a central axis of the support shaft, and that is detached, at a time of a secondary collision, from the lower jacket with the second teeth kept in meshing engagement with the first teeth; and
an energy absorbing unit including a pair of energy absorbing portions each including a restraining portion restrained in the column axial direction by the lower jacket, a first portion extending upward from the restraining portion in the column axial direction, a fold-back portion, and a second portion formed by folding back the energy absorbing portion at the fold-back portion, the energy absorbing portions being separated from each other in the orthogonal direction, and a coupling portion that couples the second portions of the energy absorbing portions together and that moves together with the second tooth defining member at the time of the secondary collision, wherein
at the time of the secondary collision, the energy absorbing portions allow the fold-back portions to move downward in the column axial direction to absorb impact energy while guiding downward movement of the second tooth defining member in the column axial direction between facing edges of the energy absorbing portions.

2. The steering system according to claim 1 , wherein the support shaft is supported between the first portion and the second portion of each of the energy absorbing portions of the energy absorbing unit, the energy absorbing portions serving as the member supported by the lower jacket, and
at the time of the secondary collision, the support shaft guides parallel movement of the second portion with respect to the first portion.

3. The steering system according to claim 1 , wherein the first portion of each of the energy absorbing portions includes an inclined portion inclined with respect to the orthogonal direction and allowing bending rigidity to be enhanced.

4. The steering system according to claim 1 , further comprising:
an engaging protrusion supported by the lower jacket;
a second energy absorbing unit including a moving portion that moves together with the second tooth defining member at the time of the secondary collision, an engaged portion with which the engaging protrusion engages, and a second energy absorbing portion that is deformed by movement of the moving portion with respect to the engaged portion to absorb impact energy generated at the time of the secondary collision; and
a driving mechanism that advances the engaging protrusion toward an engagement position where the engaging protrusion engages with the engaged portion and that retracts the engaging protrusion toward an engagement released position where engagement with the engaged portion is released.

Assignees

• Jtekt Corp

Inventors

• Nagatani Atsumune
• Sakuda Masayoshi
• Myohoji Yu

Classifications

• B62D1/184 Primary

  Mechanisms for locking columns at selected positions · CPC title

• B62D1/195 Primary

  Yieldable supports for the steering column · CPC title

• B62D1/192

  Yieldable or collapsible columns · CPC title