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US4470489A Expired / Lapsed US ⏱️ 0.0 years remaining

System for controlling a power transmission of a four-wheel drive vehicle

Assignee: Subaru Corp
•
Filing: 1982-07-19
•
Granted: 1984-09-11
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Expires: 2002-07-19
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Abstract

Abstract A system for a four-wheel drive vehicle for automatically changing a power transmission system of the engine of the vehicle from four-wheel driving system to two-wheel driving system in accordance with the steering angle during the turning of a corner. The transmission system is provided for transmitting a power from the engine to main driving two-wheel, and a fluid pressure controlled friction clutch is provided for transmitting the power of the engine to two wheels other than the main driving two-wheel. A steering angle sensor is provided for producing a steering angle signal dependent on the steering angle. A control system is provided to respond to the steering angle signal for decreasing the pressure of the pressure oil applied to the clutch thereby to cause the slip of the clutch during the turning of the corner.

Inventors

  • 👤 Fujio Makita

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 12:47
CPC Classifications
B; B60; B60K; B60K23/00; B60K23/08; B60K23/0808; B60K17/00; B60K17/34; F; F16; F16D; F16D48/00; F16D48/06; F16D48/066; F16D48/02; F16D2048/0257; F16D2048/0272; F16D2500/00; F16D2500/10; F16D2500/104; F16D2500/10406; F16D2500/10431; F16D2500/10443; F16D2500/1045; F16D2500/30; F16D2500/302; F16D2500/3021; F16D2500/70; F16D2500/702; F16D2500/70205; F16D2500/70241; F16D2500/704; F16D2500/70402; F16D2500/70406; F16D2500/70422; F16D2500/70426

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 94 words
A system for controlling a power transmission of a four-wheel drive vehicle powered by an engine comprising: a transmission for transmitting a power of said engine to main driving two-wheel; a clutch for selectively transmitting said power to two-wheel other than said main driving two-wheel, said clutch being such that the engagement force thereof can be decreased; a steering angle sensor for producing a steering angle signal dependent on the steering angle; a control system responsive to said steering angle signal for decreasing said engagement force thereby to occur the slip of said clutch.
Claim 2
Independent Claim 94 words
A system for controlling a power transmission of a four-wheel drive vehicle powered by an engine comprising: a transmission for transmitting a power of said engine to main driving two-wheel; a clutch for selectively transmitting said power to two-wheel other than said main driving two-wheel, said clutch being such that the engagement force thereof can be decreased; a steering angle sensor for producing a steering angle signal dependent on the steering angle; a control system responsive to said steering angle signal for decreasing said engagement force thereby to occur the slip of said clutch.
Claim 3
Dependent Claim 50 words
The system for controlling a power transmission of a four-wheel drive vehicle according to claim 1 wherein said clutch is a fluid pressure controlled friction clutch, and said control system comprises a changeover valve and a drain valve for controlling pressure oil applied to said fluid pressure controlled friction clutch.

References Cited (Backward Citations)

US3165946A Cited
US2789646A Cited
GB1287029A Cited
US3963085A Cited
US4180138A Cited
US4175638A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-09-11 1988-03-12 1988-09-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-09-11 1992-03-12 1992-09-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-09-11 1996-03-12 1996-09-11 $7700.00 Window Closed / Lapsed

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