Ball-screw assembly isolator having compressible members

Patent metadata

Field	Value
Publication number	US-9873454-B2
Application number	US-201514669044-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	Aug 17, 2012
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

A ball-screw assembly isolator is provided and includes a housing, a ball-screw, a ball-screw nut, a bearing assembly, a retaining member, a second retaining member, a first compressible member and a second compressible member. The bearing assembly is located between the housing and the ball-screw. The bearing assembly includes an inner race and an outer race. The retaining member is secured by the housing. The second retaining member is secured to the ball-screw nut. The first compressible member positioned between the housing and the outer race. The second compressible member is positioned between the outer race and the retaining member. The retaining member is configured to be preloaded to exert an axial force upon the first compressible member and the second compressible member.

First claim

Having thus described the invention, it is claimed:

1. A ball-screw assembly isolator, comprising:
a housing;
a ball-screw;
a ball-screw nut;
a bearing assembly located between the housing and the ball-screw, the bearing assembly including an inner race and an outer race;
a retaining member secured by the housing and defining a retaining member recess;
a second retaining member secured to the ball-screw nut and defining a second retaining member recess;
a first compressible member positioned between the housing and the outer race; and
a second compressible member positioned between the outer race and the retaining member, the retaining member configured to preloaded to exert an axial force upon the first compressible member and the second compressible member, the outer race defining a first recess for receiving a portion of the first compressible member, the outer race defining a second recess for receiving a portion of the second compressible member, the retaining member recess for receiving a portion of the second compressible member, the second retaining member recess for receiving a portion of the first compressible member.

2. The ball-screw assembly isolator of claim 1 , wherein the second retaining member exerts a second axial force to compress the inner race against the ball-screw nut, and wherein the axial force exerted by the retaining member generally opposes the second axial force exerted by the second retaining member.

3. The ball-screw assembly isolator of claim 1 , wherein the ball-screw nut includes a ball-screw nut shoulder, and wherein the inner race is compressed against the ball-screw nut shoulder.

4. The ball-screw assembly isolator of claim 1 , wherein the first compressible member and the second compressible member are constructed from a fluorocarbon elastomer.

5. The ball-screw assembly isolator of claim 1 , wherein the retaining member is threadingly engaged with the housing.

6. A steering system, comprising:
a rack assembly;
a ball-screw assembly isolator having a ball screw in communication with the rack assembly, comprising:
a housing;
a bearing assembly located between the housing and the ball-screw, the bearing assembly including an outer race;
a retaining member secured by the housing and defining a retaining member recess;
a first compressible member positioned between the housing and the outer race; and
a second compressible member positioned between the outer race and the retaining member, the retaining member configured to be preloaded to exert an axial force upon the first compressible member and the second compressible member, the outer race defining a first recess for receiving a portion of the first compressible member, the outer race defining a second recess for receiving a portion of the second compressible member, the retaining member recess for receiving a portion of the second compressible member.

7. The steering system of claim 6 , comprising a ball-screw nut and a second retaining member that are located within the housing, wherein the second retaining member is secured to the ball-screw nut.

8. The steering system of claim 1 , wherein the bearing assembly includes an inner race, and wherein the second retaining member exerts a second axial force to compress the inner race against the ball-screw nut.

9. The steering system of claim 8 , wherein the axial force exerted by the retaining member generally opposes the second axial force exerted by the second retaining member.

Assignees

• Steering Solutions Ip Holding

Inventors

• Arlt George E
• Holm David P
• Strieter Troy P
• Shavrnoch James J
• Freed Bryan G

Classifications

• F16H25/24

  Elements essential to such mechanisms, e.g. screws, nuts (F16H25/22 takes precedence) · CPC title

• B62D3/08 Primary

  using intermediate balls or the like · CPC title

• Y10T74/18576

  including screw and nut · CPC title

• F16H57/0006

  Vibration-damping or noise reducing means specially adapted for gearings (devices for varying tension of belts, ropes or chains with damping means F16H7/0829; toothed members with construction providing vibration damping F16H55/14; reducing vibrations or noise of the gearbox casing F16H57/028; suppression of vibrations or noise of gear selectors F16H59/0208; control of hydrostatic fluid gearing preventing or reducing vibrations or noise F16H61/4183) · CPC title

• Y10T74/19744

  Rolling element engaging thread · CPC title