US3791475A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power steering apparatus
Assignee: Automobiles Citroen SA
•
Filing: 1972-03-28
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Granted: 1974-02-12
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Expires: 1992-03-28
Abstract
Abstract Power steering apparatus comprises a steering shaft, an intermediate shaft connected to actuate the steering linkage and connected to the steering shaft through a lost motion connection, fluid-operated means for actuating the steering linkage, and a distributor for controlling said actuating means. The distributor is actuated in response to relative angular displacement between the steering and intermediate shafts and means are provided for amplifying the effect of said displacement on the distributor. The power steering apparatus is associated in a single casing with means for automatically straightening the steered wheels of the vehicle.
Inventors
- 👤 J Cadiou
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:14
CPC Classifications
B; B62; B62D; B62D6/00; B62D6/02; F; F15; F15B; F15B9/00; F15B9/02; F15B9/08; F15B9/12; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18568
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
196 words
In power steering apparatus for a vehicle comprising a manually rotatable steering shaft, steering linkage, and an intermediate shaft connected to actuate said linkage and connected to be rotated by said steering shaft through a lost motion connection permitting limited relative angular displacement between said shafts, fluid pressure responsive actuating means connected to actuate said steering linkage, a source of fluid under pressure, a fluid distributor comprising a valve member mounted for translational movement and connected to control the supply of said fluid under pressure to said actuating means, the transmission means through which said valve member is actuated in response to relative displacement between said shafts, the improvement according to which said transmission means is separate and distinct from said fluid-pressure responsive actuating means and comprises a first rotatable member separate from said shafts and connected to be driven by said steering shaft, a second rotatable member separate from said shafts and connected to be driven by said intermediate shaft about the same axis as said first rotatable member, and means connected between said rotatable members and said valve member for converting relative rotation between said rotatable members into translational movement by said valve member.
Claim 2
Dependent Claim
196 words
In power steering apparatus for a vehicle comprising a manually rotatable steering shaft, steering linkage, and an intermediate shaft connected to actuate said linkage and connected to be rotated by said steering shaft through a lost motion connection permitting limited relative angular displacement between said shafts, fluid pressure responsive actuating means connected to actuate said steering linkage, a source of fluid under pressure, a fluid distributor comprising a valve member mounted for translational movement and connected to control the supply of said fluid under pressure to said actuating means, the transmission means through which said valve member is actuated in response to relative displacement between said shafts, the improvement according to which said transmission means is separate and distinct from said fluid-pressure responsive actuating means and comprises a first rotatable member separate from said shafts and connected to be driven by said steering shaft, a second rotatable member separate from said shafts and connected to be driven by said intermediate shaft about the same axis as said first rotatable member, and means connected between said rotatable members and said valve member for converting relative rotation between said rotatable members into translational movement by said valve member.
Claim 3
Dependent Claim
62 words
Apparatus as claimed in claim 1 comprising return means for automatically urging said steering shaft into a position in which the road wheels of said vehicle point straight ahead and which includes a rotatably mounted cam geared to said steering shaft and means for exerting pressure on said cam, said return means and power steering apparatus being enclosed in a common casing.
Claim 4
Dependent Claim
42 words
Apparatus as claimed in claim 1 in which said shafts are aligned on a common axis, the axis about which said rotatable members are driven is parallel to said common axis and said rotatable members are driven at the same transmission ratio.
Claim 5
Dependent Claim
125 words
Apparatus as claimed in claim 3 in which said valve member is mounted for translation iN axial alignment with the axis of said rotatable members, and said rotatable members are connected by at least two pins, each pin being connected at each end to one of said rotatable members by a ball and socket joint, and being provided with a lever projecting transversely therefrom, each lever having an end remote from said pin which is swung when the positions of said pins are changed by relative angular displacement between said rotatable members, and said transmission means comprising means for transmitting to said valve member the component of the movement of said lever ends which is parallel to the direction of translation of said valve member.
Claim 6
Dependent Claim
44 words
Apparatus as claimed in claim 4 in which said levers are of equal length, said pins are parallel to the axis of said rotatable members in the absence of relative angular displacement between said rotatable members, and said levers are longer than said pins.
Claim 7
Dependent Claim
65 words
Apparatus as claimed in claim 4 in which each pin carries the balls of the ball and socket joints by which it is connected to said rotatable members, and each ball has two part-spherical bearing surfaces one of which surfaces is circular and engages the bottom of the cooperating socket and one of which is annular and engages the peripheral wall of the cooperating socket.
Claim 8
Dependent Claim
33 words
Apparatus as claimed in claim 4 in which the end of each lever remote from the pin which carries it pivotally engages one end of a connecting link which actuates said valve member.
Claim 9
Dependent Claim
31 words
Apparatus as claimed in claim 7 in which the pivotal connections of said levers to said connecting link are centered in a plane transverse to said pins midway of their length.
Claim 10
Dependent Claim
34 words
Apparatus as claimed in claim 7 in which the pivotal connections of the levers to said connecting link lie at the same distance from the axis of said rotatable members as do said pins.
Claim 11
Dependent Claim
30 words
Apparatus as claimed in claim 7 in which said connecting link actuates said valve member through a rod which passes through a hollow shaft carrying one of said rotatable members.
Claim 12
Dependent Claim
27 words
Apparatus as claimed in claim 10 in which there are two pins and said pins are symmetrically positioned with respect to the axis of said rotatable members.
Claim 13
Dependent Claim
33 words
Apparatus as claimed in claim 11 in which said connecting link is pivotally connected to the rod actuating said valve member at a point out of line with its connections to said levers.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |