Electric recirculating ball power steering system

Patent metadata

Field	Value
Publication number	US-11780491-B2
Application number	US-201916694839-A
Country	US
Kind code	B2
Filing date	Nov 25, 2019
Priority date	Nov 25, 2019
Publication date	Oct 10, 2023
Grant date	Oct 10, 2023

Abstract

An electric power steering system includes an electric motor including a motor output shaft. The system also includes a worm operatively coupled to the motor output shaft. The system further includes a worm gear in contact with the worm and operatively coupled to an auxiliary shaft. The system yet further includes a drive gear operatively coupled to the auxiliary shaft. The system also includes a driven gear in contact with the drive gear and operatively coupled to an input shaft to drive a manual recirculating ball steering gear.

First claim

Having thus described the invention, it is claimed:

1. An electric power steering system comprising:
an electric motor including a motor output shaft;
a worm operatively coupled to the motor output shaft;
a worm gear in contact with the worm and operatively coupled to an auxiliary shaft;
a drive gear operatively coupled to the auxiliary shaft; and
a driven gear in contact with the drive gear and operatively coupled to an input shaft to drive a manual recirculating ball steering gear, wherein the motor output shaft and the input shaft are oriented perpendicular to each other, wherein the auxiliary shaft and the input shaft are oriented parallel to each other.

2. The electric power steering system of claim 1 , wherein the drive gear and the driven gear form a spur gear arrangement.

3. The electric power steering system of claim 1 , wherein the drive gear and the driven gear are helical gears.

4. The electric power steering system of claim 1 , further comprising a controller in operative communication with the electric motor and a torque sensor.

5. The electric power steering system of claim 1 , wherein an output shaft of the manual recirculating ball steering gear is operatively coupled to a Pitman arm, the Pitman arm operatively coupled to a tie rod to provide an assist torque to vehicle road wheels.

6. An electric power steering system comprising:
an electric motor having a motor output shaft;
a first gear arrangement driven by the electric motor; and
a second gear arrangement driven by the first gear arrangement, the second gear arrangement operatively coupled to an input shaft to drive a manual recirculating ball steering gear, wherein the motor output shaft and the input shaft are oriented perpendicular to each other, wherein the second gear arrangement comprises:
a drive gear operatively coupled to an auxiliary shaft that is driven by the first gear arrangement; and
a driven gear in contact with the drive gear and operatively coupled to the input shaft, wherein the auxiliary shaft and the input shaft are oriented parallel to each other.

7. The electric power steering system of claim 6 , wherein the first gear arrangement comprises:
a worm operatively coupled to the electric motor; and
a worm gear in contact with the worm and operatively coupled to an auxiliary shaft.

8. The electric power steering system of claim 6 , wherein the drive gear and the driven gear form a spur gear arrangement.

9. The electric power steering system of claim 6 , wherein the drive gear and the driven gear are helical gears.

10. The electric power steering system of claim 6 , further comprising a controller in operative communication with the electric motor and a torque sensor.

11. The electric power steering system of claim 6 , wherein an output shaft of the manual recirculating ball steering gear is operatively coupled to a Pitman arm, the Pitman arm operatively coupled to a tie rod to provide an assist torque to vehicle road wheels.

Assignees

• Steering Solutions Ip Holding

Inventors

• Yang Kun
• Schmitt Peter D
• Beyerlein Jeffrey E

Classifications

• B62D5/0463 Primary

  calculating assisting torque from the motor based on driver input · CPC title

• B62D3/04

  of worm type · CPC title

• B62D5/0415

  the axes being coaxial · CPC title

• B62D7/166

  substantially perpendicular, e.g. between tie-rod and steering knuckle · CPC title

• B62D5/04 Primary

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