Steering device

Patent metadata

Field	Value
Publication number	US-9428218-B2
Application number	US-201514667308-A
Country	US
Kind code	B2
Filing date	Mar 24, 2015
Priority date	Apr 7, 2014
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

A rack-parallel electric power steering device includes a housing that covers the periphery of a speed reducer, and a drain valve provided in the housing. The drain valve includes a first case, a second case mounted to the outer peripheral portion of a bottom portion of the first case, and a valve element that closely contacts a bottom surface of the first case. A through hole is formed in the bottom portion of the first case. The second case includes a bottom portion which is disposed with a gap from the bottom portion of the first case and in which discharge holes are formed. The valve element is an elastic member that blocks an opening portion of the through hole of the first case and that is held between the first case and the second case.

First claim

What is claimed is:

1. A steering device comprising:
a steered shaft that moves in an axial direction on the basis of rotation of a steering shaft to steer steered wheels;
a motor that applies an assist force to the steered shaft via a speed reducer; and
a housing that covers a periphery of the speed reducer, wherein
a drain valve is provided at a bottom wall portion of the housing under the speed reducer in a vertical direction, and
the drain valve comprises:
a first case that opens into the housing and that has a bottomed cylindrical shape having a bottom portion in which a through hole is formed;
a second case that is mounted to an outer peripheral portion of the bottom portion of the first case and that has a bottomed cylindrical shape having a bottom portion which is disposed with a gap from the bottom portion of the first case and in which a discharge hole is formed; and
a valve element formed of an elastic member that closely contacts a bottom surface of the first case to block an opening portion of the through hole and that is held between the first case and the second case by having a top surface of the valve element contact the bottom surface of the first case and a bottom surface of the valve element contact a top surface of the second case.

2. The steering device according to claim 1 , wherein
the valve element includes a blocking piece supported in a cantilever manner with a portion held between the first case and the second case, and a distal-end portion which is a free end of the blocking piece blocks the opening portion of the through hole.

3. The steering device according to claim 2 , wherein
the through hole is formed in the bottom portion of the first case at a position offset from a center of the bottom portion,
the valve element is held between the first case and the second case at a portion of a peripheral edge portion of a bottom surface of the first case, which is the most distant from the through hole, and
the blocking piece is disposed to extend from the portion of the valve element held between the first case and the second case to the opening portion of the through hole.

4. The steering device according to claim 2 , wherein
when a direction extending from the portion of the blocking piece supported in a cantilever manner to the distal-end portion is defined as an extending direction of the blocking piece, the through hole is a long hole that extends in a direction that is orthogonal to the extending direction of the blocking piece.

5. The steering device according to claim 1 , wherein:
a pair of the through holes formed in the bottom portion of the first case; and
the valve element includes a blocking piece, a center portion of which is held between the first case and the second case at an intermediate position between respective opening portions of the through holes, and both end portions of the blocking piece which are free ends of the blocking piece block the respective opening portions of the through holes.

6. The steering device according to claim 5 , wherein
when a direction extending from a portion of the blocking piece held between the first case and the second case to the both end portions is defined as an extending direction of the blocking piece, the through holes are long holes that extend in a direction that is orthogonal to the extending direction of the blocking piece.

7. The steering device according to claim 1 , wherein
the valve element is held between an outer peripheral surface of the first case and an inner peripheral surface of the second case.

8. The steering device according to claim 1 , wherein
the valve element includes:
an annular portion disposed along a peripheral edge of the bottom surface of the first case, with the annular portion held between the first case and the second case by having a top surface of the annular portion contact the bottom surface of the first case and a bottom surface of the annular portion contact the top surface of the second case, and
a blocking piece formed to extend from an inner peripheral surface of the annular portion, the blocking piece formed to extend from a location on the inner peripheral surface of the annular portion that is the most distant from the through hole of the first case to the through hole in order to block the opening portion of the through hole.

9. The steering device according to claim 8 , wherein
the valve element further includes a tubular portion formed in a tubular shape at an outer edge of the annular portion, the tubular portion disposed along an outer peripheral surface of a flange portion of the first case and a notch of the flange portion, and held between an outer peripheral surface of the first case and an inner peripheral surface of the second case by having the tubular portion contact both the outer peripheral surface of the first case and the inner peripheral surface of the second case.

Assignees

• Jtekt Corp

Inventors

• Yamamoto Yasuharu

Classifications

• F16K15/148

  the closure elements being fixed in their centre · CPC title

• B62D5/0424 Primary

  the axes of motor and final driven element of steering gear, e.g. rack, being parallel · CPC title

• B62D5/04 Primary

  electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear · CPC title

• F16K15/144

  the closure elements being fixed along all or a part of their periphery · CPC title

• F16K15/16

  with tongue-shaped laminae · CPC title