US3727992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-lock brake control system
Assignee: Motors Liquidation Co
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Filing: 1971-03-15
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Granted: 1973-04-17
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Expires: 1991-03-15
Abstract
Abstract An anti-lock brake control system has a brake pressure modulator operated by a single solenoid controlled on-off valve which effects brake apply, brake release, and brake pressure hold modes. The hold mode is achieved by dithering the solenoid valve. An electronic circuit responsive to rotation of a braked wheel supplies signals to the solenoid valve to effect the various modes. The circuit includes a wheel speed recovery circuit for supplying to the valve during wheel recovery an operating signal for dithering the valve at a first level of wheel acceleration and for producing a brake apply signal above a higher value of wheel acceleration.
Inventors
- 👤 L Bowler
- 👤 J Harned
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:09
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/173; B60T2210/00; B60T2210/10; B60T2210/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
181 words
An anti-lock brake control system for a wheeled vehicle comprising means responsive to the rotation of a braked wheel for detecting an incipient wheel lock-up condition and for thereupon producing a brake release signal, means for generating an acceleration signal according to acceleration of the braked wheel, wheel recovery means enabled by the brake release signal including a multivibrator, a first signal level detector responsive to the acceleration signal and connected to the multivibrator for effecting a rapidly oscillating multivibrator output above a first predetermined level of wheel acceleration, and a second signal level detector responsive to the acceleration signal and connected to the multivibrator for effecting a brake apply signal from the multivibrator, and brake pressure modulating means responsive to the brake release signal for relieving brake pressure when incipient wheel lockup is detected to allow positive wheel acceleration, responsive to the oscillating output signal for holding brake pressure at a relatively constant value during the predetermined range of wheel acceleration, and responsive to the brake apply signal for reapplying brake pressure when the wheel acceleration exceeds the second value.
Claim 2
Dependent Claim
181 words
An anti-lock brake control system for a wheeled vehicle comprising means responsive to the rotation of a braked wheel for detecting an incipient wheel lock-up condition and for thereupon producing a brake release signal, means for generating an acceleration signal according to acceleration of the braked wheel, wheel recovery means enabled by the brake release signal including a multivibrator, a first signal level detector responsive to the acceleration signal and connected to the multivibrator for effecting a rapidly oscillating multivibrator output above a first predetermined level of wheel acceleration, and a second signal level detector responsive to the acceleration signal and connected to the multivibrator for effecting a brake apply signal from the multivibrator, and brake pressure modulating means responsive to the brake release signal for relieving brake pressure when incipient wheel lockup is detected to allow positive wheel acceleration, responsive to the oscillating output signal for holding brake pressure at a relatively constant value during the predetermined range of wheel acceleration, and responsive to the brake apply signal for reapplying brake pressure when the wheel acceleration exceeds the second value.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |