US4193642A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Skid control system
Assignee: ZF Active Safety US Inc
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Filing: 1976-01-13
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Granted: 1980-03-18
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Expires: 1996-01-13
Abstract
Abstract A skid control system which compares a current representative of wheel deceleration with an alterable reference current using an integrating comparator to control the brakes of a vehicle. The reference current has an initial value which represents a wheel deceleration indicative of an incipient skid condition and is increased to a substantially higher value after the current representative of wheel deceleration reaches the initial reference current value and is reduced to a very low value after a predetermined period of time. When the current representative of wheel deceleration exceeds the reference current by a predetermined degree as determined by the integrating comparator, the brakes are released. The brakes are reapplied after the current representative of wheel deceleration no longer exceeds the reference current at a time determined by the integrating comparator.
Inventors
- 👤 Roger L. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:22
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/176; B60T8/1761; B60T8/17613; G; G01; G01P; G01P15/00; G01P15/16; G01P3/00; G01P3/42; G01P3/56; G01P3/58
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
334 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of a first predetermined magnitude to represent a first rate of decline of said wheel speed including means for altering the magnitude of said reference current in response to an output signal to a reference current of a second predetermined magnitude to represent a second rate of decline of said wheel speed so that said reference current of said first and second predetermined magnitudes represents a predetermined wheel deceleration profile having said first and second rates of decline of said wheel speed; comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal upon the attainment of a predetermined relationship therebetween to cause said reference generating means to alter the magnitude of said reference current, said comparator means subsequently comparing said current representative of said wheel deceleration and said reference current of said first and second predetermined magnitudes for providing a subsequent output signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of said first and second predetermined magnitudes, said comparator means being responsive to the degree that said current representative of wheel deceleration and said reference current depart from said predetermined relationship therebetween in a manner so as to be approximately responsive to the degree that the wheel deceleration departs from said predetermined wheel deceleration profile for terminating said further output signal; and brake modulating means operative with said comparator means so that said brake is not modulated responsive to the provision of said first-mentioned output signal but is modulated responsive to the provision of said subsequent output signal, said brake modulating means being further responsive to the termination of said subsequent output signal for terminating the modulation of the brake.
Claim 2
Dependent Claim
334 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of a first predetermined magnitude to represent a first rate of decline of said wheel speed including means for altering the magnitude of said reference current in response to an output signal to a reference current of a second predetermined magnitude to represent a second rate of decline of said wheel speed so that said reference current of said first and second predetermined magnitudes represents a predetermined wheel deceleration profile having said first and second rates of decline of said wheel speed; comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal upon the attainment of a predetermined relationship therebetween to cause said reference generating means to alter the magnitude of said reference current, said comparator means subsequently comparing said current representative of said wheel deceleration and said reference current of said first and second predetermined magnitudes for providing a subsequent output signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of said first and second predetermined magnitudes, said comparator means being responsive to the degree that said current representative of wheel deceleration and said reference current depart from said predetermined relationship therebetween in a manner so as to be approximately responsive to the degree that the wheel deceleration departs from said predetermined wheel deceleration profile for terminating said further output signal; and brake modulating means operative with said comparator means so that said brake is not modulated responsive to the provision of said first-mentioned output signal but is modulated responsive to the provision of said subsequent output signal, said brake modulating means being further responsive to the termination of said subsequent output signal for terminating the modulation of the brake.
Claim 3
Dependent Claim
32 words
A skid control system according to claim 1 wherein said means for altering the magnitude of said reference current increases the magnitude of said reference current in response to said output signal.
Claim 4
Dependent Claim
55 words
A skid control system according to claim 1 wherein said comparator means compares the magnitude of said current representative of wheel deceleration and the magnitude of said reference current and provides said output signal when the magnitude of said current representative of wheel deceleration attains a predetermined relationship with the magnitude of said reference current.
Claim 5
Dependent Claim
32 words
A skid control system according to claim 3 wherein said means for altering the magnitude of said reference current increases the magnitude of said reference current in response to said output signal.
Claim 6
Dependent Claim
42 words
A skid control system according to claim 3 wherein said comparator means is responsive to the period of time that said current representative of wheel deceleration exceeds the magnitude thereof when said predetermined relationship is attained for terminating said further output signal.
Claim 7
Dependent Claim
32 words
A skid control system according to claim 5 wherein said means for altering the magnitude of said reference current increases the magnitude of said reference current in response to said output signal.
Claim 8
Dependent Claim
26 words
A skid control system according to claim 1 wherein said first predetermined magnitude of wheel deceleration is between 22 and 27 feet per second 2 .
Claim 9
Dependent Claim
26 words
A skid control system according to claim 1 wherein said second predetermined magnitude of wheel deceleration is between 115 and 140 feet per second 2 .
Claim 10
Dependent Claim
243 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of a predetermined magnitude including means for altering the magnitude of said reference current in response to an output signal; control means for providing a brake release signal and a brake reapplication signal, said control means including comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal a predetermined delay after the attainment of a predetermined relationship therebetween, said control means subsequently comparing said current representative of said wheel deceleration and said reference current of altered magnitude for providing said brake reapplication signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of altered magnitude, said control means being responsive to the degree that said current representative of wheel deceleration and said reference current depart from said predetermined relationship therebetween so that the attainment of said predetermined relationship is increasingly delayed for increasing departures of said current representative of wheel deceleration and said reference current from said predetermined relationship therebetween; and brake modulating means responsive to said brake release signal for effecting the release of said brake and responsive to said brake reapplication signal for effecting the reapplication of said brake.
Claim 11
Dependent Claim
243 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of a predetermined magnitude including means for altering the magnitude of said reference current in response to an output signal; control means for providing a brake release signal and a brake reapplication signal, said control means including comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal a predetermined delay after the attainment of a predetermined relationship therebetween, said control means subsequently comparing said current representative of said wheel deceleration and said reference current of altered magnitude for providing said brake reapplication signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of altered magnitude, said control means being responsive to the degree that said current representative of wheel deceleration and said reference current depart from said predetermined relationship therebetween so that the attainment of said predetermined relationship is increasingly delayed for increasing departures of said current representative of wheel deceleration and said reference current from said predetermined relationship therebetween; and brake modulating means responsive to said brake release signal for effecting the release of said brake and responsive to said brake reapplication signal for effecting the reapplication of said brake.
Claim 12
Dependent Claim
26 words
A skid control system according to claim 9 wherein said first predetermined magnitude of wheel deceleration is between 115 and 140 feet per second 2 .
Claim 13
Dependent Claim
26 words
A skid control system according to claim 9 wherein said second predetermined magnitude of wheel deceleration is between 1 and 6 feet per second 2 .
Claim 14
Dependent Claim
32 words
A skid control system according to claim 9 wherein said means for altering the magnitude of said reference current decreases the magnitude of said reference current in response to said output signal.
Claim 15
Dependent Claim
58 words
A skid control system according to claim 9 wherein said control means compares the magnitude of said current representative of wheel deceleration and the magnitude of said reference current and provides said output signal said predetermined delay after the magnitude of said current representative of wheel deceleration attains a predetermined relationship with the magnitude of said reference current.
Claim 16
Dependent Claim
32 words
A skid control system according to claim 13 wherein said means for altering the magnitude of said reference current decreases the magnitude of said reference current in response to said output signal.
Claim 17
Dependent Claim
46 words
A skid control system according to claim 13 wherein said control means is responsive to the period of time that the magnitude of said current representative of wheel deceleration exceeds the magnitude thereof prior to the attainment of said predetermined relationship causing said brake reapplication signal.
Claim 18
Dependent Claim
32 words
A skid control system according to claim 15 wherein said means for altering the magnitude of said reference current decreases the magnitude of said reference current in response to said output signal.
Claim 19
Dependent Claim
43 words
A skid control system according to claim 9 wherein said control means is responsive to the period of time that said current representative of wheel deceleration exceeds the magnitude thereof prior to the attainment of said predetermined relationship causing said brake reapplication signal.
Claim 20
Dependent Claim
32 words
A skid control system according to claim 17 wherein said means for altering the magnitude of said reference current decreases the magnitude of said reference current in response to said output signal.
Claim 21
Dependent Claim
17 words
A skid control system according to claim 9 wherein said predetermined delay is a period of time.
Claim 22
Dependent Claim
32 words
A skid control system according to claim 19 wherein said means for altering the magnitude of said reference current decreases the magnitude of said reference current in response to said output signal.
Claim 23
Dependent Claim
309 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of predetermined magnitude including means for increasing the magnitude of said reference current in response to an output signal and for decreasing the magnitude of said reference current after a predetermined delay after said first output signal; comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal upon the attainment of a predetermined relationship therebetween, said comparator means subsequently comparing said current representative of said wheel deceleration and said reference current of increased magnitude for providing a subsequent output signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of increased magnitude, said comparator still subsequently comparing said current representative of wheel deceleration and said reference current of decreased magnitude for terminating said subsequent output signal upon the termination of said predetermined relationship between said current representative of wheel deceleration and said reference current of decreased magnitude, said comparator being responsive to the degree that said current representative of wheel deceleration and said reference current depart from said predetermined relationship therebetween so that the attainment of said predetermined relationship is increasingly delayed for increasing departures of said current representative of wheel deceleration and said reference current from said predetermined relationship therebetween; and brake modulating means operative with said comparator means so that said brake is not modulated responsive to the provision of said first-mentioned output signal but is modulated responsive to said subsequent output signal, said brake modulating means being further responsive to the termination of said subsequent output signal for terminating the modulation of said brake.
Claim 24
Dependent Claim
309 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of predetermined magnitude including means for increasing the magnitude of said reference current in response to an output signal and for decreasing the magnitude of said reference current after a predetermined delay after said first output signal; comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal upon the attainment of a predetermined relationship therebetween, said comparator means subsequently comparing said current representative of said wheel deceleration and said reference current of increased magnitude for providing a subsequent output signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of increased magnitude, said comparator still subsequently comparing said current representative of wheel deceleration and said reference current of decreased magnitude for terminating said subsequent output signal upon the termination of said predetermined relationship between said current representative of wheel deceleration and said reference current of decreased magnitude, said comparator being responsive to the degree that said current representative of wheel deceleration and said reference current depart from said predetermined relationship therebetween so that the attainment of said predetermined relationship is increasingly delayed for increasing departures of said current representative of wheel deceleration and said reference current from said predetermined relationship therebetween; and brake modulating means operative with said comparator means so that said brake is not modulated responsive to the provision of said first-mentioned output signal but is modulated responsive to said subsequent output signal, said brake modulating means being further responsive to the termination of said subsequent output signal for terminating the modulation of said brake.
Claim 25
Dependent Claim
103 words
A skid control system according to claim 21 wherein said reference current represents a first predetermined magnitude of wheel deceleration before said reference current is altered to represent a wheel deceleration of increased magnitude, said altered reference current representing a wheel deceleration of increased magnitude represents a second predetermined magnitude of wheel deceleration which is of substantially greater magnitude than said first predetermined magnitude of wheel deceleration, and said altered reference current representing a wheel deceleration of decreased magnitude represents a third predetermined magnitude of wheel deceleration which is of substantially decreased magnitude than said first and second predetermined magnitudes of wheel deceleration.
Claim 26
Dependent Claim
26 words
A skid control system according to claim 22 wherein said first predetermined magnitude of wheel deceleration is between 22 and 27 feet per second 2 .
Claim 27
Dependent Claim
26 words
A skid control system according to claim 22 wherein said second predetermined magnitude of wheel deceleration is between 115 and 140 feet per second 2 .
Claim 28
Dependent Claim
26 words
A skid control system according to claim 22 wherein said third predetermined magnitude of wheel deceleration is between 1 and 6 feet per second 2 .
Claim 29
Dependent Claim
61 words
A skid control system according to claim 22 wherein said first predetermined magnitude of wheel deceleration is between 22 and 27 feet per second 2 , said second predetermined magnitude of wheel deceleration is between 115 and 140 feet per second 2 , and said third predetermined magnitude of wheel deceleration is between 1 and 6 feet per second 2 .
Claim 30
Dependent Claim
55 words
A skid control system according to claim 21 wherein said comparator means compares the magnitude of said current representative of wheel deceleration and the magnitude of said reference current and provides said output signal when the magnitude of said current representative of wheel deceleration attains a predetermined relationship with the magnitude of said reference current.
Claim 31
Dependent Claim
46 words
A skid control system according to claim 27 wherein said comparator means is responsive to the period of time that the magnitude of said current representative of wheel deceleration exceeds the magnitude thereof prior to the attainment of said predetermined relationship causing said brake reapplication signal.
Claim 32
Dependent Claim
43 words
A skid control system according to claim 21 wherein said comparator means is responsive to the period of time that said current representative of wheel deceleration exceeds the magnitude thereof prior to the attainment of said predetermined relationship causing said brake reapplication signal.
Claim 33
Dependent Claim
17 words
A skid control system according to claim 21 wherein said predetermined delay is a period of time.
Claim 34
Dependent Claim
309 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of predetermined magnitude representing a first predetermined magnitude of wheel deceleration including means for increasing the magnitude of said reference current to represent a second predetermined magnitude of wheel deceleration of substantially greater magnitude than said first predetermined magnitude of wheel deceleration in response to an output signal and for decreasing the magnitude of said reference current to represent a third predetermined magnitude of wheel deceleration which is of substantially decreased magnitude than said first and second predetermined magnitudes of wheel deceleration after a predetermined delay after said first output signal; comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal upon the attainment of a predetermined relationship therebetween, said comparator means subsequently comparing said current representative of said wheel deceleration and said reference current of increased magnitude for providing a subsequent output signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of increased magnitude, said comparator still subsequently comparing said current representative of wheel deceleration and said reference current of decreased magnitude for terminating said subsequent output signal upon the termination of said predetermined relationship between said current representative of wheel deceleration and said reference current of decreased magnitude; and brake modulating means operative with said comparator means so that said brake is not modulated responsive to the provision of said first-mentioned output signal but is modulated responsive to said subsequent output signal, said brake modulating means being further responsive to the termination of said subsequent output signal for terminating the modulation of said brake.
Claim 35
Dependent Claim
309 words
A skid control system for a vehicle having at least one wheel and a brake for said wheel comprising: wheel deceleration detecting means for providing a current representative of the deceleration of at least one wheel; reference generating means for generating a reference current of predetermined magnitude representing a first predetermined magnitude of wheel deceleration including means for increasing the magnitude of said reference current to represent a second predetermined magnitude of wheel deceleration of substantially greater magnitude than said first predetermined magnitude of wheel deceleration in response to an output signal and for decreasing the magnitude of said reference current to represent a third predetermined magnitude of wheel deceleration which is of substantially decreased magnitude than said first and second predetermined magnitudes of wheel deceleration after a predetermined delay after said first output signal; comparator means for comparing said current representative of wheel deceleration and said reference current for providing said output signal upon the attainment of a predetermined relationship therebetween, said comparator means subsequently comparing said current representative of said wheel deceleration and said reference current of increased magnitude for providing a subsequent output signal upon the attainment of said predetermined relationship between said current representative of wheel deceleration and said reference current of increased magnitude, said comparator still subsequently comparing said current representative of wheel deceleration and said reference current of decreased magnitude for terminating said subsequent output signal upon the termination of said predetermined relationship between said current representative of wheel deceleration and said reference current of decreased magnitude; and brake modulating means operative with said comparator means so that said brake is not modulated responsive to the provision of said first-mentioned output signal but is modulated responsive to said subsequent output signal, said brake modulating means being further responsive to the termination of said subsequent output signal for terminating the modulation of said brake.
Claim 36
Dependent Claim
26 words
A skid control system according to claim 31 wherein said first predetermined magnitude of wheel deceleration is between 22 and 27 feet per second 2 .
Claim 37
Dependent Claim
26 words
A skid control system according to claim 31 wherein said second predetermined magnitude of wheel deceleration is between 115 and 140 feet per second 2 .
Claim 38
Dependent Claim
26 words
A skid control system according to claim 31 wherein said third predetermined magnitude of wheel deceleration is between 1 and 6 feet per second 2 .
Claim 39
Dependent Claim
61 words
A skid control system according to claim 31 wherein said first predetermined magnitude of wheel deceleration is between 22 and 27 feet per second 2 , said second predetermined magnitude of wheel deceleration is between 115 and 140 feet per second 2 , and said third predetermined magnitude of wheel deceleration is between 1 and 6 feet per second 2 .
References Cited (Backward Citations)
US3017145A
Cited
US3606490A
Cited
US3652132A
Cited
US3870376A
Cited
US3710186A
Cited
US3574426A
Cited
US3690735A
Cited
US3912340A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-03-18 | 1983-09-17 | 1984-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-18 | 1987-09-17 | 1988-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-18 | 1991-09-17 | 1992-03-18 | $7700.00 | Window Closed / Lapsed |