Apparatus for use in turning steerable vehicle wheels

Patent metadata

Field	Value
Publication number	US-12054202-B2
Application number	US-201916962251-A
Country	US
Kind code	B2
Filing date	Jan 18, 2019
Priority date	Jan 18, 2018
Publication date	Aug 6, 2024
Grant date	Aug 6, 2024

Abstract

An apparatus for use in turning steerable vehicle wheels includes a rotatable shaft that is rotatable relative to the vehicle to effect turning movement of the steerable vehicle wheels. A ball nut assembly is connected with an externally threaded portion of the rotatable shaft. The ball nut assembly moves axially relative to the rotatable shaft upon rotation of the rotatable shaft relative to the ball nut assembly. A steering member is connected to the ball nut assembly and at least one steerable vehicle wheel. The steering member moves with the ball nut assembly relative to the shaft. An electrical motor is connected with the rotatable shaft. The motor is operable to effect rotation of the rotatable shaft relative to the ball nut assembly to turn the steerable vehicle wheels.

First claim

Having described the invention, the following is claimed:

1. An apparatus for use in turning steerable vehicle wheels comprising:
a rotatable shaft that is rotatable relative to a vehicle to effect turning movement of the steerable vehicle wheels;
a ball nut assembly connected with an externally threaded portion of the rotatable shaft, the ball nut assembly moving linearly along the rotatable shaft upon rotation of the rotatable shaft relative to the ball nut assembly;
a steering member connected to the ball nut assembly and at least one steerable vehicle wheel, the steering member moving linearly with the linearly moving ball nut assembly relative to the rotatable shaft; and
an electrical motor connected with the rotatable shaft, the motor being operable to effect rotation of the rotatable shaft relative to the ball nut assembly to turn the steerable vehicle wheels.

2. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 wherein a first gear rotatable in response to rotation of a steering wheel is disposed in meshing engagement with a second gear connected to the rotatable shaft.

3. An apparatus for use in turning steerable vehicle wheels as set forth in claim 2 wherein the first gear rotates about a first axis and the second gear rotates about a second axis extending transverse to the first axis, the rotatable shaft and the second gear being coaxial.

4. An apparatus for use in turning steerable vehicle wheels as set forth in claim 3 wherein the first and second gears are bevel gears.

5. An apparatus for use in turning steerable vehicle wheels as set forth in claim 3 wherein the first and second gears increase the torque applied to the steering column.

6. An apparatus for use in turning steerable vehicle wheels as set forth in claim 3 wherein a gear box supports said first and second gears for rotation about the first and second axes.

7. An apparatus for use in turning steerable vehicle wheels as set forth in claim 6 wherein the gear box has an input shaft connected to the first gear, the input shaft being connected to a steering wheel and rotatable relative to a housing of the gear box in response to rotation of the steering wheel.

8. An apparatus for use in turning steerable vehicle wheels as set forth in claim 7 wherein a support member connects the gear box, the electric motor and a housing supporting the rotatable shaft.

9. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 wherein the rotatable shaft and the steering member are coaxial.

10. An apparatus for use in turning steerable vehicle wheels as set forth in claim 9 wherein the rotatable shaft extends into an interior of the steering member.

11. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 wherein the ball nut assembly has a radially extending portion that extends through an opening in a housing supporting the rotatable shaft for rotation, the radially extending portion being connected to the steering member connected to at least one steerable vehicle wheel.

12. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 further including at least one vehicle condition sensor and a control unit connected with the at least one vehicle condition sensor, the at least one vehicle condition sensor providing an output to the control unit, the control unit being connected with the motor and being operable to control the operation of the motor as a function of the output from the at least one vehicle condition sensor.

13. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 further including at least one of a torque sensor for sensing a torque applied to a steering wheel and a position sensor for sensing a position of the steering wheel and a control unit connected with the at least one of the torque sensor and the position sensor, the at least one of the torque sensor and the position sensor providing an output to the control unit, the control unit being connected with the motor and being operable to control an operation of the motor as a function of the output from the at least one of the torque sensor and the position sensor.

14. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 wherein the linearly moving ball nut assembly applies a linear force to the steering member to move the steering member linearly with the ball nut assembly relative to the rotatable shaft.

15. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 further including a housing that rotatably supports the rotatable shaft, the ball nut assembly being prevented from rotating relative to the housing.

16. An apparatus for use in turning steerable vehicle wheels as set forth in claim 1 wherein the steering member moves linearly together with the ball nut assembly in a same direction as the ball nut assembly.

17. An apparatus for use in turning steerable vehicle wheels comprising:
a rotatable shaft that is rotatable relative to a vehicle to effect turning movement of the steerable vehicle wheels;
a ball nut assembly connected with an externally threaded portion of the rotatable shaft, the ball nut assembly moving axially relative to the rotatable shaft upon rotation of the rotatable shaft relative to the ball nut assembly;
a steering member connected to at least one steerable vehicle wheel, the steering member being directly connected to the ball nut assembly and movable with the ball nut assembly relative to the shaft; and
an electrical motor operably connected with the rotatable shaft, the motor effecting rotation of the rotatable shaft relative to the ball nut assembly to turn the steerable vehicle wheels.

18. An apparatus for use in turning steerable vehicle wheels as set forth in claim 17 wherein the ball nut assembly has body and an arm that is integrally formed with the body as a single monolithic piece, the arm extending radially from the through an opening in a housing that rotatably supports the rotatable shaft, the steering member being directly connected to the ball nut assembly at the arm.

Assignees

• Trw Automotive Us Llc
• Zf Active Safety & Electronics Us Llc

Inventors

• Boyle Kevin E
• Cartwright Mark A
• Jacobson Paul E
• Noah Bruce C
• Schoon Benjamin W

Classifications

• F16H25/2204

  with balls · CPC title

• F16H1/14

  comprising conical gears only · CPC title

• B62D5/046

  Controlling the motor · CPC title

• B62D5/0424 Primary

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

• B62D5/0448 Primary

  Ball nuts · CPC title