US3744852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Skid control system
Assignee: ZF Active Safety US Inc
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Filing: 1971-08-23
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Granted: 1973-07-10
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Expires: 1991-08-23
Abstract
Abstract A skid control system for a wheeled vehicle having a brake pressure modulator for relieving brake actuation in response to a first control signal which is representative of a detected skid condition and for modulating brake actuation thereafter in accordance with the sign and magnitude of second control signal which is representative of the sum of the rate of change of wheel acceleration during spin up and the rate of change of brake pressure.
Inventors
- 👤 H Riordan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:10
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/32; B60T8/17; B60T8/176; B60T8/1761; B60T8/17613; Y; Y10; Y10S; Y10S303/00; Y10S303/02; Y10S303/03; Y10S303/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
191 words
In a skid control system for controlling fluid pressure actuated brakes of at least one wheel of a wheeled vehicle by controlling the fluid pressure to the brakes, said system comprising: modulating meAns responsive to a first control signal for relieving the pressure to the brakes and to a second control signal for modulating the magnitude of the fluid pressure to the brakes as a function of the sign and magnitude of said second control signal, skid detection means for detecting the occurrence of an incipient skid condition at the one wheel and for providing said first control signal to said modulating means in response thereto, second means including pressure transducer means for providing an indication of the magnitude of the rate of change of brake pressure and an indication of the sign of the rate of change of brake pressure for providing said second control signal during spin-up of the wheel and for varying said second control signal as said function of said indication of the magnitude of the rate of change of brake pressure and said indication of the sign of the rate of change of the brake pressure.
Claim 2
Dependent Claim
191 words
In a skid control system for controlling fluid pressure actuated brakes of at least one wheel of a wheeled vehicle by controlling the fluid pressure to the brakes, said system comprising: modulating meAns responsive to a first control signal for relieving the pressure to the brakes and to a second control signal for modulating the magnitude of the fluid pressure to the brakes as a function of the sign and magnitude of said second control signal, skid detection means for detecting the occurrence of an incipient skid condition at the one wheel and for providing said first control signal to said modulating means in response thereto, second means including pressure transducer means for providing an indication of the magnitude of the rate of change of brake pressure and an indication of the sign of the rate of change of brake pressure for providing said second control signal during spin-up of the wheel and for varying said second control signal as said function of said indication of the magnitude of the rate of change of brake pressure and said indication of the sign of the rate of change of the brake pressure.
Claim 3
Dependent Claim
33 words
The system of claim 1 with said second means varying the magnitude of said second control signal as a function of the magnitude of the rate of change of acceleration of the wheel.
Claim 4
Dependent Claim
63 words
The system of claim 2 with said second means varying the magnitude of said second control signal in accordance with the sum of said rate of change of acceleration and of said rate of change of brake pressure whereby the magnitude of said second control signal is indicative of the magnitude of the rate of change of retarding force at the one wheel.
Claim 5
Dependent Claim
28 words
The system of claim 3 with said modulating means responsive to said second control signal to maintain the rate of change of retarding force to be approximately zero.
Claim 6
Dependent Claim
51 words
The system of claim 4 with said modulating means increasing or decreasing pressure in accordance with the sign of said second control signal, said second means determining the sign of said second control signal in accordance with the sign of said sum and of said rate of change of brake pressure.
Claim 7
Dependent Claim
267 words
In a skid control system for controlling fluid pressure actuated brakes of at least one wheel of a wheeled vehicle by controlling the fluid pressure to the brakes, said system comprising: modulating means responsive to a first control signal for relieving the pressure to the brakes and to a second control signal for modulating the magnitude of the fluid pressure to the brakes as a function of the sign and magnitude of said second control signal, skid detection means for detecting the occurrence of an incipient skid condition at the one wheel and for providing said first control signal to said modulating means in response thereto, second means for providing said second control signal during spin-up of the one wheel after said pressure to the brakes is relieved including pressure transducer means for providing an indication of the magnitude of the rate of change of brake pressure and an indication of the sign of the rate of change of the brake pressure, and means for detecting the rate of change of acceleration of the one wheel during spin-up, said second means including means varying said second control signal as a function of the sum of the magnitude of said rate of change of acceleration and the magnitude of said rate of change of brake pressure so that the magnitude of said second control signal is indicative of the magnitude of the rate of change of retarding force at the one wheel and for additionally varying the sign of said second control signal as a function of the sign of the rate of change of the brake pressure.
Claim 8
Dependent Claim
267 words
In a skid control system for controlling fluid pressure actuated brakes of at least one wheel of a wheeled vehicle by controlling the fluid pressure to the brakes, said system comprising: modulating means responsive to a first control signal for relieving the pressure to the brakes and to a second control signal for modulating the magnitude of the fluid pressure to the brakes as a function of the sign and magnitude of said second control signal, skid detection means for detecting the occurrence of an incipient skid condition at the one wheel and for providing said first control signal to said modulating means in response thereto, second means for providing said second control signal during spin-up of the one wheel after said pressure to the brakes is relieved including pressure transducer means for providing an indication of the magnitude of the rate of change of brake pressure and an indication of the sign of the rate of change of the brake pressure, and means for detecting the rate of change of acceleration of the one wheel during spin-up, said second means including means varying said second control signal as a function of the sum of the magnitude of said rate of change of acceleration and the magnitude of said rate of change of brake pressure so that the magnitude of said second control signal is indicative of the magnitude of the rate of change of retarding force at the one wheel and for additionally varying the sign of said second control signal as a function of the sign of the rate of change of the brake pressure.
Claim 9
Dependent Claim
156 words
In a skid control system for controlling fluid pressure actuated brakes of at least one wheel of a wheeled vehicle by controlling the fluid pressure to the brakes, said system comprising: modulating means responsive to a first control signal for relieving the pressure to the brakes and to a second control signal for modulating the fluid pressure to the brakes as a function of the sign and magnitude of said second control signal, skid detection means for detecting the occurrence of an incipient skid condition at the one wheel and for providing sAid first control signal to said modulating means in response thereto, and second means including pressure transducer means for detecting the magnitude of the rate of change of the brake pressure for providing said second control signal during spin-up of the wheel and for varying said second control signal as said function of the magnitude of the rate of change of the brake pressure.
Claim 10
Dependent Claim
156 words
In a skid control system for controlling fluid pressure actuated brakes of at least one wheel of a wheeled vehicle by controlling the fluid pressure to the brakes, said system comprising: modulating means responsive to a first control signal for relieving the pressure to the brakes and to a second control signal for modulating the fluid pressure to the brakes as a function of the sign and magnitude of said second control signal, skid detection means for detecting the occurrence of an incipient skid condition at the one wheel and for providing sAid first control signal to said modulating means in response thereto, and second means including pressure transducer means for detecting the magnitude of the rate of change of the brake pressure for providing said second control signal during spin-up of the wheel and for varying said second control signal as said function of the magnitude of the rate of change of the brake pressure.
References Cited (Backward Citations)
US3362757A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |