US4893518A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric steering apparatus
Assignee: NSK Ltd
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Filing: 1988-04-06
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Granted: 1990-01-16
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Expires: 2008-04-06
Abstract
Abstract An electric steering apparatus which effects position adjustment by electric drive has a screw shaft parallel to upper and lower columns. A nut member rotatably supported by a housing fixed to a bracket is fixed against movement in the axial direction of the screw shaft and threadably engaged with a screw portion provided at one end of the screw shaft. In a preferred embodiments, the other end of the screw shaft is pivotally connected to the upper column for pivotal movement relative to the bracket in the direction of tilt, the nut member is self-aligning in the housing, and the nut member is rotatively driven by an electric motor to move the screw shaft in the axial direction and thereby move the upper column, whereby position adjustment can be accomplished. The apparatus is provided with a back-lash preventing device in which the screw shaft is pressed against the nut member in a radial direction and the threadably engaged portions of the screw shaft and the nut member are urged against each other.
Inventors
- 👤 Sakae Matsumoto
- 👤 Mitsuo Ichikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:37
CPC Classifications
B; B62; B62D; B62D1/00; B62D1/02; B62D1/16; B62D1/18; B62D1/181; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19623; Y10T74/1987; Y10T74/19893; Y10T74/19898; Y10T74/19902
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
390 words
An electric steering apparatus comprising: a lower column fixed to a vehicle body and having a housing provided thereon; an upper column having a tilting pivot portion and a screw shaft pivot portion, said upper column being pivotally attached to said lower column at said tilting pivot portion so as to be tiltable with respect to said lower column; a lower shaft rotatably received in said lower column and having a first end and a second end, said first end being connected to a steering gear; an upper shaft rotatably received in said upper column for tilting with said upper column and having a first end connected to a steering wheel and a second end connected to said second end of said lower shaft through a universal joint such that an angle formed between respective axes of said upper and lower shafts may be changed by tilting of said upper shaft with said upper column; a screw shaft having a non-threaded first end portion pivotally connected directly to said screw shaft pivot portion of said upper column, and a second end portion formed with a screw thread; nut means rotatable by an electric motor and having a threaded portion engaged with said screw thread of said screw shaft; ball bearing means mounted in said housing and comprising two inner races provided on a surface of said nut means, two outer races fitted in said housing, and two groups of balls provided between said inner races and said outer races, said ball bearing means being mounted in said housing in such a manner as to support said nut means for rotation relative to said screw thread and as to prevent said nut means from moving in an axial direction of said lower column and from moving in a direction perpendicular to said lower column, said screw shaft thus moving in the axial direction of said lower column upon rotation of said nut means by said motor while pivoting relative to said screw shaft pivot portion; aligning means for aligning a rotational axis of said nut means with an axis of said screw shaft during said pivoting of said screw shaft; and back-lash eliminating means for eliminating back-lash by pressing on said non-threaded portion of said screw shaft such that said screw thread presses against said threaded portion of said nut means.
Claim 2
Dependent Claim
390 words
An electric steering apparatus comprising: a lower column fixed to a vehicle body and having a housing provided thereon; an upper column having a tilting pivot portion and a screw shaft pivot portion, said upper column being pivotally attached to said lower column at said tilting pivot portion so as to be tiltable with respect to said lower column; a lower shaft rotatably received in said lower column and having a first end and a second end, said first end being connected to a steering gear; an upper shaft rotatably received in said upper column for tilting with said upper column and having a first end connected to a steering wheel and a second end connected to said second end of said lower shaft through a universal joint such that an angle formed between respective axes of said upper and lower shafts may be changed by tilting of said upper shaft with said upper column; a screw shaft having a non-threaded first end portion pivotally connected directly to said screw shaft pivot portion of said upper column, and a second end portion formed with a screw thread; nut means rotatable by an electric motor and having a threaded portion engaged with said screw thread of said screw shaft; ball bearing means mounted in said housing and comprising two inner races provided on a surface of said nut means, two outer races fitted in said housing, and two groups of balls provided between said inner races and said outer races, said ball bearing means being mounted in said housing in such a manner as to support said nut means for rotation relative to said screw thread and as to prevent said nut means from moving in an axial direction of said lower column and from moving in a direction perpendicular to said lower column, said screw shaft thus moving in the axial direction of said lower column upon rotation of said nut means by said motor while pivoting relative to said screw shaft pivot portion; aligning means for aligning a rotational axis of said nut means with an axis of said screw shaft during said pivoting of said screw shaft; and back-lash eliminating means for eliminating back-lash by pressing on said non-threaded portion of said screw shaft such that said screw thread presses against said threaded portion of said nut means.
Claim 3
Dependent Claim
51 words
An electric steering apparatus according to claim 1, wherein said aligning means includes said outer races of said ball bearing means, and said outer races are configured such that said balls of said ball bearing means shift along said outer races in accordance with the pivoting movement of said screw shaft.
Claim 4
Dependent Claim
47 words
An electric steering apparatus according to claim 1, wherein said aligning means includes curved inner portions of said housing, and said outer races of said ball bearing means are configured to shift along said cured inner portions in accordance with the pivoting movement of said screw shaft.
Claim 5
Dependent Claim
33 words
An electric steering apparatus according to the claim 1, wherein said back-lash eliminating means also presses said first end portion of said screw shaft toward said screw shaft pivot portion of said housing.
Claim 6
Dependent Claim
333 words
An electric steering apparatus comprising: a lower column fixed to a vehicle body and having a housing provided thereon; an upper column telescopically connected to said lower column; a lower shaft rotatably received in said lower column and having a first end and a second end, said first end being connected to a steering gear; an upper shaft rotatably received in said upper column for movement with said upper column relative to said lower column and having a first end connected to a steering wheel and a second end connected to said second end of said lower shaft such that the connected second ends may move axially but not rotatably relative to each other; a screw shaft having a non-threaded first end portion connected to said upper column and a second end portion formed with a screw thread; nut means rotatable by an electric motor and having a threaded portion engaged with said screw thread of said screw shaft; ball bearing means mounted in said housing and comprising two inner races provided on a surface of said nut means, two outer races fitted in said housing, and two groups of balls provided between said inner races and said outer races, said ball bearing means supporting said nut means in such a manner as to prevent said nut means form moving in an axial direction of said lower column but to permit said nut means to rotate relative to said screw shaft, said screw shaft thus moving in the axial direction of said lower column upon rotation of said nut means by said motor; first back-lash eliminating means for eliminating back-lash by pressing said non-threaded portion of said screw shaft so that said screw thread of said screw shaft presses against said threaded portion of said nut means; and second back-lash eliminating means for eliminating back-lash by pressing said ball bearing means so that each said inner race presses against a corresponding said outer race through an associated one of said groups of balls.
Claim 7
Dependent Claim
333 words
An electric steering apparatus comprising: a lower column fixed to a vehicle body and having a housing provided thereon; an upper column telescopically connected to said lower column; a lower shaft rotatably received in said lower column and having a first end and a second end, said first end being connected to a steering gear; an upper shaft rotatably received in said upper column for movement with said upper column relative to said lower column and having a first end connected to a steering wheel and a second end connected to said second end of said lower shaft such that the connected second ends may move axially but not rotatably relative to each other; a screw shaft having a non-threaded first end portion connected to said upper column and a second end portion formed with a screw thread; nut means rotatable by an electric motor and having a threaded portion engaged with said screw thread of said screw shaft; ball bearing means mounted in said housing and comprising two inner races provided on a surface of said nut means, two outer races fitted in said housing, and two groups of balls provided between said inner races and said outer races, said ball bearing means supporting said nut means in such a manner as to prevent said nut means form moving in an axial direction of said lower column but to permit said nut means to rotate relative to said screw shaft, said screw shaft thus moving in the axial direction of said lower column upon rotation of said nut means by said motor; first back-lash eliminating means for eliminating back-lash by pressing said non-threaded portion of said screw shaft so that said screw thread of said screw shaft presses against said threaded portion of said nut means; and second back-lash eliminating means for eliminating back-lash by pressing said ball bearing means so that each said inner race presses against a corresponding said outer race through an associated one of said groups of balls.
Claim 8
Dependent Claim
43 words
An electric steering apparatus according to claim 5, wherein said second back-lash eliminating means comprises male and female threaded members engaged with one another and threadably adjustable for pressing against said ball bearing means to eliminate back-lash associated with said ball bearing means.
Claim 9
Dependent Claim
318 words
An electric steering apparatus comprising: a lower column fixed to a vehicle body; an upper column having a tilting pivot portion and a screw shaft pivot portion, said upper column being pivotally attached to said lower column at said tilting pivot portion so as to be tiltable with respect to said lower column; a lower shaft rotatably received in said lower column and having a first end and a second end, said first end being connected to a steering gear; an upper shaft rotatably received in said upper column for tilting movement with said upper column and having a first end connected to a steering wheel and a second end connected to said second end of said lower shaft through a universal joint such that an angle formed between respective axes of said upper and lower shafts may be changed by tilting of said upper shaft with said upper column; a screw shaft having a non-threaded first end portion pivotally connected directly to said screw shaft pivot portion of said upper column, and a second end portion formed with a screw thread; nut means rotatable by an electric motor and having a threaded portion engaged with said screw thread of said screw shaft; ball bearing means supporting said nut means for rotation relative to said screw thread and in such a manner as to prevent said nut means from moving in an axial direction of said lower column and from moving in a direction perpendicular to said lower column, said screw shaft thus being movable in the axial direction of said lower column upon rotation of said nut means by said electric motor while pivoting relative to said screw shaft pivot portion; aligning means for aligning a rotational axis of said nut means with the axis of said screw shaft during movement of said screw shaft; and pressing means for pressing said ball bearing means to eliminate back-lash.
Claim 10
Dependent Claim
318 words
An electric steering apparatus comprising: a lower column fixed to a vehicle body; an upper column having a tilting pivot portion and a screw shaft pivot portion, said upper column being pivotally attached to said lower column at said tilting pivot portion so as to be tiltable with respect to said lower column; a lower shaft rotatably received in said lower column and having a first end and a second end, said first end being connected to a steering gear; an upper shaft rotatably received in said upper column for tilting movement with said upper column and having a first end connected to a steering wheel and a second end connected to said second end of said lower shaft through a universal joint such that an angle formed between respective axes of said upper and lower shafts may be changed by tilting of said upper shaft with said upper column; a screw shaft having a non-threaded first end portion pivotally connected directly to said screw shaft pivot portion of said upper column, and a second end portion formed with a screw thread; nut means rotatable by an electric motor and having a threaded portion engaged with said screw thread of said screw shaft; ball bearing means supporting said nut means for rotation relative to said screw thread and in such a manner as to prevent said nut means from moving in an axial direction of said lower column and from moving in a direction perpendicular to said lower column, said screw shaft thus being movable in the axial direction of said lower column upon rotation of said nut means by said electric motor while pivoting relative to said screw shaft pivot portion; aligning means for aligning a rotational axis of said nut means with the axis of said screw shaft during movement of said screw shaft; and pressing means for pressing said ball bearing means to eliminate back-lash.
Claim 11
Dependent Claim
86 words
An electric steering apparatus according to claim 7, including a housing provided on said lower column, and wherein: said ball bearing means comprises two inner races provided on a surface of said nut means, two outer races fitted in said housing, and two groups of balls provided between said inner and outer races, and said pressing means comprises male and female threaded members engaged with one another and threadably adjustable for pressing against said ball bearing means to eliminate back-lash associated with said ball bearing means.
Claim 12
Dependent Claim
51 words
An electric steering apparatus according to claim 7, wherein said aligning means includes said outer races of said ball bearing means, and said outer races are configured such that said balls of said ball bearing means shift along said outer races in accordance with the pivoting movement of said screw shaft.
Claim 13
Dependent Claim
56 words
An electric steering apparatus according to claim 7, including a housing provided on said lower column, and wherein said aligning means includes curved inner portions of said housing, and said outer races of said ball bearing means are configured to shift along said curved inner portions in accordance with the pivoting movement of said screw shaft.
References Cited (Backward Citations)
US4503504A
Cited
JPS59230861A
Cited
US4633732A
Cited
US4602520A
Cited
US4528862A
Cited
US4669325A
Cited
US4753122A
Cited
US4739673A
Cited
US4691587A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-15 | 1993-07-17 | 1994-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-15 | 1997-07-17 | 1998-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-15 | 2001-07-17 | 2002-01-16 | $7700.00 | Window Closed / Lapsed |