Highly integrated eps system

Patent metadata

Field	Value
Publication number	US-2020361522-A1
Application number	US-202016862745-A
Country	US
Kind code	A1
Filing date	Apr 30, 2020
Priority date	May 16, 2019
Publication date	Nov 19, 2020
Grant date	—

Abstract

Technical solutions for a motor assembly for an electric power steering system are provided. The motor assembly comprises a motor configured to rotate a motor shaft to apply a drive torque to an output shaft of a steering column. The motor assembly also comprises a circuit card assembly including a torque and angle sensor disposed upon a printed circuit board and configured to measure a differential angle between rotational positions of the output shaft and an input shaft. The printed circuit board of the circuit card assembly is disposed perpendicular to a rotational axis of the steering column. The motor assembly also comprises an enclosure coupled to the motor and containing the circuit card assembly and a worm shaft coupled to rotate with the motor shaft and having a worm disposed helically thereabout for driving a worm gear coupled to the output shaft.

First claim

What is claimed is:

1 . A motor assembly for an electric power steering system comprising:
a motor configured to rotate a motor shaft to apply a drive torque to an output shaft of a steering column; a circuit card assembly including a torque and angle sensor disposed upon a printed circuit board and configured to measure a differential angle between rotational positions of the output shaft and an input shaft; and wherein the printed circuit board of the circuit card assembly is disposed perpendicular to a rotational axis of the steering column.

2 . The motor assembly of claim 1 , wherein the circuit card assembly also includes a handwheel angle sensor configured to measure an absolute angle of the input shaft.

3 . The motor assembly of claim 1 , further comprising a motor position sensor in communication with the circuit card assembly and configured to measure a rotational position of the motor shaft.

4 . The motor assembly of claim 3 , wherein the motor position sensor is spaced apart from the circuit card assembly and connected thereto by a flexible conductor.

5 . The motor assembly of claim 3 , wherein the motor shaft is coupled to a worm shaft having a worm disposed helically thereabout, with the motor shaft extending between the motor position sensor and the worm shaft.

6 . The motor assembly of claim 3 , wherein the motor shaft is coupled to a worm shaft having a worm disposed helically thereabout, with the worm shaft extending between the motor shaft and the motor position sensor.

7 . The motor assembly of claim 1 , further comprising:
a worm shaft coupled to rotate with the motor shaft, the worm shaft having a worm disposed helically thereabout for driving a worm gear coupled to the output shaft; and an enclosure containing the circuit card assembly and the worm shaft and the worm gear.

8 . The motor assembly of claim 1 , wherein the motor is a brushless type motor.

9 . A motor assembly for an electric power steering system comprising:
a motor configured to rotate a motor shaft to apply a drive torque to an output shaft of a steering column; an enclosure coupled to the motor and containing a circuit card assembly, the circuit card assembly including a torque and angle sensor disposed upon a printed circuit board and configured to measure a differential angle between rotational positions of the output shaft and an input shaft; a worm shaft coupled to rotate with the motor shaft, the worm shaft having a worm disposed helically thereabout for driving a worm gear coupled to the output shaft; and wherein the worm shaft and the worm gear are each disposed within the enclosure.

10 . The motor assembly of claim 9 , wherein the printed circuit board of the circuit card assembly is disposed perpendicular to a rotational axis of the steering column.

11 . The motor assembly of claim 9 , wherein the circuit card assembly also includes a handwheel angle sensor configured to measure an absolute angle of the input shaft.

12 . The motor assembly of claim 9 , further comprising a motor position sensor in communication with the circuit card assembly and configured to measure a rotational position of the motor shaft.

13 . The motor assembly of claim 12 , wherein the motor position sensor is spaced apart from the circuit card assembly and connected thereto by a flexible conductor.

14 . The motor assembly of claim 12 , wherein the motor shaft extends between the motor position sensor and the worm shaft.

15 . The motor assembly of claim 12 , wherein the worm shaft extends between the motor shaft and the motor position sensor.

16 . The motor assembly of claim 9 , wherein the motor is a brushless type motor.

17 . A motor assembly for an electric power steering system comprising:
a motor configured to rotate a motor shaft to apply a drive torque to an output shaft of a steering column; a circuit card assembly including a torque and angle sensor disposed upon a printed circuit board and configured to measure a differential angle between rotational positions of the output shaft and an input shaft; the circuit card assembly also including a position sensor disposed upon the printed circuit board and configured to measure a rotational position of the motor shaft.

18 . The motor assembly of claim 17 , further comprising a shaft position wheel configured to rotate with the motor shaft and to be sensed by the position sensor on the circuit card assembly.

19 . The motor assembly of claim 17 , further comprising an enclosure containing the circuit card assembly, the enclosure directly coupled to the motor.

20 . The motor assembly of claim 19 , further comprising a worm shaft coupled to rotate with the motor shaft and having a worm disposed helically thereabout and engaging a worm gear coupled to the output shaft; and wherein the worm shaft and the worm gear are disposed within the enclosure.

Assignees

• Steering Solutions Ip Holding

Inventors

• Weimin Yin
• Yang Kun
• Longuemare Pierre C
• Pattok Eric

Classifications

• B62D6/10

  characterised by means for sensing {or determining} torque · CPC title

• B62D5/0403

  characterised by constructional features, e.g. common housing for motor and gear box · CPC title

• B62D15/02

  Steering position indicators {; Steering position determination; Steering aids} · CPC title

• B62D5/04 Primary

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

• B62D5/0409 Primary

  Electric motor acting on the steering column · CPC title