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US4218958A Expired / Lapsed US ⏱️ 0.0 years remaining

Servo-steering system for vehicles

Assignee: Daimler Benz AG
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Filing: 1978-03-10
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Granted: 1980-08-26
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Expires: 1998-03-10
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Abstract

Abstract A servo-steering mechanism for vehicles with a feedback of a load-dependent reaction moment onto the steering hand wheel by means of at least one reaction pressure cylinder connected with a working pressure chamber, in which a reaction pressure piston operating onto the steering hand wheel is adapted to be actuated in one direction of its piston axis by the working pressure and in the other direction of its piston axis is adapted to be supported at a support spring and is also adapted to come into abutment at a stop fixed relative to the reaction pressure cylinder, when the working pressure has been brought to a value corresponding to the prestress of the support spring; between its starting position with an unstressed support spring and its shut-off or turn-off position at the associated stop the reaction pressure piston thereby comes into additional abutment at least at one reducing spring counteracting the working pressure, whereby the reducing spring is adapted to be supported either directly or by way of at least one further reducing spring at a counter abutment of the reaction pressure cylinder.

Inventors

  • 👤 Klaus Katz
  • 👤 Reinhold Abt
  • 👤 Jaromir Bordovsky
  • 👤 Wolfgang Pfundstein
  • 👤 Georg Wingert

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 11:55
CPC Classifications
B; B62; B62D; B62D5/00; B62D5/06; B62D5/08; B62D5/20; B62D5/24

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 215 words
A servo-steering mechanism for vehicles, comprising feedback means for feeding back a load-dependent reaction moment to a hand steering wheel, the feedback means including at least one reaction pressure cylinder means operatively connected with a working pressure chamber means of the servo-steering mechanism, cylinder means and operatively connected to the steering hand wheel, said reaction pressure piston means being operable to be actuated in one axial direction by a working pressure of the working pressure chamber means, a support spring means for supporting said reaction piston means in the other axial direction, and abutment means fixed with respect to the reaction pressure cylinder means, said reaction piston means being adapted to come into abutment with the fixed abutment means when the working pressure in the working pressure chamber means reaches a value corresponding to a prestress of the support spring means, characterized in that the abutment means is fixed on the reaction pressure cylinder means at least one reducing spring means acting in a direction opposite the working pressure is provided for additionally supporting the reaction pressure piston means between a starting position with an essentially unstressed support spring means and a shut-off position at the abutment means said reducing spring means being supported at the abutment means provided on the reaction pressure cylinder means.
Claim 2
Dependent Claim 215 words
A servo-steering mechanism for vehicles, comprising feedback means for feeding back a load-dependent reaction moment to a hand steering wheel, the feedback means including at least one reaction pressure cylinder means operatively connected with a working pressure chamber means of the servo-steering mechanism, cylinder means and operatively connected to the steering hand wheel, said reaction pressure piston means being operable to be actuated in one axial direction by a working pressure of the working pressure chamber means, a support spring means for supporting said reaction piston means in the other axial direction, and abutment means fixed with respect to the reaction pressure cylinder means, said reaction piston means being adapted to come into abutment with the fixed abutment means when the working pressure in the working pressure chamber means reaches a value corresponding to a prestress of the support spring means, characterized in that the abutment means is fixed on the reaction pressure cylinder means at least one reducing spring means acting in a direction opposite the working pressure is provided for additionally supporting the reaction pressure piston means between a starting position with an essentially unstressed support spring means and a shut-off position at the abutment means said reducing spring means being supported at the abutment means provided on the reaction pressure cylinder means.
Claim 3
Dependent Claim 27 words
A servo-steering mechanism according to claim 1, characterized in that the abutment means is formed by a spring ring plate mounted on the reaction pressure cylinder means.
Claim 4
Dependent Claim 20 words
A servo-steering mechanism according to claim 1, characterized in that the abutment means is formed by a spring plate sleeve.
Claim 5
Dependent Claim 21 words
A servo-steering mechanism according to claim 1, characterized in that the reducing spring means is supported directly at the abutment means.
Claim 6
Dependent Claim 30 words
A servo-steering mechanism according to claim 1, characterized in that at least one further reducing spring means is provided for supporting the first-mentioned reducing spring means on the abutment means.
Claim 7
Dependent Claim 21 words
A servo-steering mechanism according to claim 1, characterized in that the at least one reducing spring means has a progressive characteristic.
Claim 8
Dependent Claim 54 words
A servo-steering mechanism according to claim 6, characterized in that the at least one reducing spring means is formed of a plurality of cylindrical windings having a variable pitch arranged in such a manner that, during the spring deflection, more than one spring winding is stressed sequentially into mutual abutment to form a block.
Claim 9
Dependent Claim 37 words
A servo-steering mechanism according to claim 7, characterized in that the pitch is substantially symmetrical to a center plane of the at least one reducing spring means which extends perpendicular to a longitudinal axis of the spring.
Claim 10
Dependent Claim 29 words
A servo-steering mechanism according to claim 8 characterized in that the pitch of the reducing spring means is one of a sine and cosine function of the winding angle.
Claim 11
Dependent Claim 37 words
A servo-steering mechanism according to claim 9, characterized in that a start of the first spring winding beginning at a spring end of the reducing spring means is located substantially in the minimum of a pitch function.
Claim 12
Dependent Claim 19 words
A servo-steering mechanism according to claim 9, characterized in that several reducing spring means are provided and are series-connected.
Claim 13
Dependent Claim 23 words
A servo-steering mechanism according to claim 11, characterized in that at least some of said series-connected reducing spring means have different spring characteristics.
Claim 14
Dependent Claim 20 words
A servo-steering mechanism according to claim 9, characterized in that the reducing spring means is supported directly the abutment means.
Claim 15
Dependent Claim 30 words
A servo-steering mechanism according to claim 9, characterized in that at least one further reducing spring means is provided for supporting the first-mentioned reducing spring means on the abutment means.
Claim 16
Dependent Claim 48 words
A servo-steering mechanism according to claim 6, characterized in that the at least one reducing spring means is formed of a plurality of windings having a pitch which is substantially symmetrical to a center place of the reducing spring means perpendicular to a longitudinal axis of the spring.
Claim 17
Dependent Claim 32 words
A servo-steering mechanism according to claim 6, characterized in that the pitch of the at least one reducing spring means is one of a sine and cosine function of the winding angle.
Claim 18
Dependent Claim 37 words
A servo-steering mechanism according to claim 6, characterized in that a start of the first spring winding beginning at a spring end of the reducing spring means is located substantially in the minimum of a pitch function.
Claim 19
Dependent Claim 18 words
A servo-steering mechanism according to claim 1, characterized in that several reducing spring means are provided and series-connected.
Claim 20
Dependent Claim 19 words
A servo-steering mechanism according to claim 18, characterized in that said series-connected reducing spring means have different spring characteristics.
Claim 21
Dependent Claim 22 words
A servo-steering mechanism according to claim 19, characterized in that at least one of the reducing spring means has a progressive characteristic.

References Cited (Backward Citations)

US2985145A Cited
US3444786A Cited
US3719124A Cited
US4003404A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-08-26 1984-02-25 1984-08-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-08-26 1988-02-25 1988-08-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-08-26 1992-02-25 1992-08-26 $7700.00 Window Closed / Lapsed

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