BEARING MECHANISM HAVING SLIDING BEARING

• US 20100278467A1
• Filed: 10/21/2008
• Published: 11/04/2010
• Est. Priority Date: 10/23/2007
• Status: Active Grant

• Current Assignee: Oiles Corporation, Jtekt Corporation (Toyota Motor Corporation)
• Original Assignee: Oiles Corporation, Jtekt Corporation (Toyota Motor Corporation)
• Inventors: Ohara, Yoshihide, Tanaka, Takahiro, Kaida, Hidetoshi, Oki, Eiji, Hirose, Masahiko, Hashimoto, Masaaki
• Granted Patent: US 8,272,785 B2
• Time in Patent Office: Days
• US Class Current: 384/283
• CPC Class Codes: B62D 3/12 of rack-and-pinion type
• CPC Class Codes: F16C 2208/58 Several materials as provided for in F16C2208/30 - F16C2208/54 mentioned as option
• CPC Class Codes: F16C 2208/66 Acetals, e.g. polyoxymethylene [POM]
• CPC Class Codes: F16C 2208/78 Polyethylene [PE], e.g. ultra-high molecular weight polyethylene [UHMWPE]
• CPC Class Codes: F16C 2226/50 Positive connections
• CPC Class Codes: F16C 2326/24 Steering systems, e.g. steering rods or columns in general B62D
• CPC Class Codes: F16C 2361/61 Toothed gear systems, e.g. support of pinion shafts in general F16H57/02
• CPC Class Codes: F16C 29/002 Elastic or yielding linear bearings or bearing supports
• CPC Class Codes: F16C 29/02 Sliding-contact bearings
• CPC Class Codes: F16C 33/20 Sliding surface consisting mainly of plastics F16C33/22 - F16C33/28 take precedence
• CPC Class Codes: F16C 35/02 in the case of sliding-contact bearings
• CPC Class Codes: F16H 2055/281 Cylindrical or half-cylindrical bushings around the rack, e.g. using special wedges to reduce play

Abstract

A bearing mechanism 1 includes a housing 3 having a cylindrical inner peripheral surface 2, a rack shaft 5 inserted and secured in the housing 3 and having a cylindrical outer peripheral surface 4, and a sliding bearing 6 interposed between the inner peripheral surface 2 of the housing 3 and the outer peripheral surface 4 of the rack shaft 5.

Claims

1. A bearing mechanism comprising:

a housing having a cylindrical inner peripheral surface, a rack shaft inserted and secured in said housing and having a cylindrical outer peripheral surface, and a sliding bearing interposed between the inner peripheral surface of said housing and the outer peripheral surface of said rack shaft,

wherein said housing has a retaining groove in an inner Peripheral surface thereof, and said sliding bearing includes;

a cylindrical bearing body;

one slit provided in said bearing body and extending from one axial end face of said bearing body toward another axial end face of said bearing body;

another slit provided in said bearing body and extending from the other axial end face of said bearing body toward the one axial end face of said bearing body;

a plurality of sliding surfaces provided on an inner side of said bearing body and at least partially spaced apart from each other in a direction about an axis;

at least one fitting groove provided in an outer surface of said bearing body;

an elastic ring which is fitted in said fitting groove in such a manner as to project radially from the outer surface of said bearing body and to reduce a diameter of said bearing body; and

restricting means which is disposed in said retaining groove of said housing with an elastic interference and elastically restricts the axial movement of said bearing body with respect to said housing,

said elastic ring being fitted at an outer peripheral surface thereof to said housing with an interference,

said bearing body being fitted on the outer peripheral surface of said rack shaft by tightening said rack shaft with the resiliency of said elastic ring by means of said sliding surfaces,

said restricting means including a projection which is integrally formed on the outer peripheral surface of said bearing body in such a manner as to project radially outward toward said retaining groove and another elastic ring fitted on said projection by surrounding said projection,

said retaining groove being defined by a pair of wall surfaces perpendicular to an axial direction of said housing and a wall surface extending in a direction about an axis of said housing,

said other elastic ring being elastically compressed by being brought into contact with the pair of wall surfaces defining said retaining groove.

2. The bearing mechanism according to claim 1, wherein said projection of said restricting means is disposed in said retaining groove in the inner peripheral surface of said housing with an elastic interference based on said other elastic ring.

3. The bearing mechanism according to claim 1, wherein said projection of said restricting means has an annular groove for fitting said other elastic ring therein, said projection of said restricting means has an outer peripheral surface thereof disposed in said retaining groove with clearances with the pair of wall surfaces, respectively, and said other elastic ring partially projects from the annular groove in an axial direction, and is, at a partially projecting portion thereof, in contact with the pair of wall surfaces.

4. A sliding bearing which is interposed between a cylindrical inner peripheral surface having a retaining groove in a housing and a cylindrical outer peripheral surface of a rack shaft which is inserted and secured in said housing, comprising:

a cylindrical bearing body;

one slit provided in said bearing body and extending from one axial end face of said bearing body toward another axial end face of said bearing body;

another slit provided in said bearing body and extending from the other axial end face of said bearing body toward the one axial end face of said bearing body;

a plurality of sliding surfaces provided on an inner side of said bearing body and at least partially spaced apart from each other in a direction about an axis;

at least one fitting groove provided in an outer surface of said bearing body;

an elastic ring which is fitted in said fitting groove in such a manner as to project radially from the outer surface of said bearing body and to reduce a diameter of said bearing body; and

restricting means which is adapted to be disposed in said retaining groove of said housing with an elastic interference and is adapted to elastically restrict the axial movement of said bearing body with respect to said housing,

said elastic ring being adapted to be fitted at an outer peripheral surface thereof to said housing with an interference,

said bearing body being adapted to be fitted on the outer peripheral surface of said rack shaft by tightening said rack shaft with the resiliency of said elastic ring by means of said sliding surfaces,

said restricting means including a projection which is integrally formed on the outer peripheral surface of said bearing body in such a manner as to project radially outward so as to be directed toward said retaining groove and another elastic ring fitted on said projection by surrounding said projection,

said retaining groove being defined by a pair of wall surfaces perpendicular to an axial direction of said housing and a wall surface extending in a direction about an axis of said housing,

said other elastic ring being adapted to be elastically compressed by being brought into contact with the pair of wall surfaces defining said retaining groove.