US3833268A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wheel slip control system for automotive vehicles and the like
Assignee: Echlin Inc
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Filing: 1972-03-10
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Granted: 1974-09-03
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Expires: 1992-03-10
Abstract
Abstract A control system for varying the pressure applied to fluidcontrolled brake actuating mechanisms upon detection of both a wheel deceleration in excess of a predetermined threshold and a subsequent incremental decrease in wheel velocity greater than a continuously-varying reference increment Delta v of wheel speed. This reference increment Delta v is inversely related to a variable reference signal which is directly related to the rate of change of wheel speed. Thus, the continuously-varying reference increment of wheel speed Delta v is inversely related to the rate of change of wheel speed. Consequently, the period of time between occurrence of a wheel deceleration in excess of said predetermined threshold and the relief of brake line fluid pressure is shorter when wheel speed decreases rapidly and longer when wheel speed decreases slowly. Compensation is thus made for varying road and load conditions, and for the characteristics of the braking mechanism which applies braking force to the wheel.
Inventors
- 👤 J Fleagle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:08
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/32; B60T8/34; B60T8/36; B60T8/361; B60T8/17; B60T8/176; B60T8/1763; B60T8/17633; G; G01; G01P; G01P1/00; G01P1/07; G01P1/08; G01P1/10; G01P1/103; G01P15/00; G01P15/02; G01P15/08; G01P15/0891; G01P15/16; G01P3/00; G01P3/42; G01P3/56
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
115 words
A wheel slip control system for a vehicle having at least one wheel with an associated brake and an actuating mechanism therefor, comprising: 1. first means operative to generate an output whenever the change in rotational velocity of a selected wheel, from the value of said rotational velocity at the time the rate of change of said rotational velocity exceeds a predetermined threshold, exceeds a variable reference increment of wheel speed inversely related to said rate of change of rotational velocity; and 2. second means operative in response to said output to effeCt a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 2
Dependent Claim
115 words
A wheel slip control system for a vehicle having at least one wheel with an associated brake and an actuating mechanism therefor, comprising: 1. first means operative to generate an output whenever the change in rotational velocity of a selected wheel, from the value of said rotational velocity at the time the rate of change of said rotational velocity exceeds a predetermined threshold, exceeds a variable reference increment of wheel speed inversely related to said rate of change of rotational velocity; and 2. second means operative in response to said output to effeCt a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 3
Dependent Claim
32 words
second means operative in response to said output to effeCt a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 4
Dependent Claim
32 words
second means operative in response to said output to effeCt a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 5
Dependent Claim
88 words
The system according to claim 1 wherein said first means includes means operative to extend the duration of said output whenever both a a predetermined period of time is exceeded by the period of time during which the change in rotational velocity of the selected wheel, from the value of said rotational velocity at the time said rate of change of rotational velocity exceeds said predetermined threshold, exceeds a variable reference increment of wheel speed and b the rotational acceleration of said selected wheel exceeds a predetermined threshold.
Claim 6
Dependent Claim
36 words
second means operative in response to at least said second variable-width pulse to effect a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 7
Dependent Claim
36 words
second means operative in response to at least said second variable-width pulse to effect a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 8
Dependent Claim
23 words
second signal means operative to generate a second signal directly proportional to the rate of change of rotational velocity of said selected wheel;
Claim 9
Dependent Claim
23 words
second signal means operative to generate a second signal directly proportional to the rate of change of rotational velocity of said selected wheel;
Claim 10
Dependent Claim
11 words
monitoring the rate of change of the speed of said wheel;
Claim 11
Dependent Claim
11 words
monitoring the rate of change of the speed of said wheel;
Claim 12
Dependent Claim
26 words
second logic means operative to generate an output in response to either said second variable-width pulse output from said second comparison means or the output from
Claim 13
Dependent Claim
26 words
second logic means operative to generate an output in response to either said second variable-width pulse output from said second comparison means or the output from
Claim 14
Dependent Claim
26 words
first logic means operative in response to either said first variable-width pulse or said first output of said timer means to actuate said gating circuit means.
Claim 15
Dependent Claim
26 words
first logic means operative in response to either said first variable-width pulse or said first output of said timer means to actuate said gating circuit means.
Claim 16
Dependent Claim
22 words
generating a variable reference increment of wheel spaced inversely related to the rate of change of the speed of said wheel; and
Claim 17
Dependent Claim
22 words
generating a variable reference increment of wheel spaced inversely related to the rate of change of the speed of said wheel; and
Claim 18
Dependent Claim
57 words
third logic means operative in response to the coincidence of a second output from said timer means, a third variable-width pulse output from said third comparison means, and an output from said second logic means to extend the output of said second logic means after termination of said second variable-width pulse output from said second comparison means.
Claim 19
Dependent Claim
57 words
third logic means operative in response to the coincidence of a second output from said timer means, a third variable-width pulse output from said third comparison means, and an output from said second logic means to extend the output of said second logic means after termination of said second variable-width pulse output from said second comparison means.
Claim 20
Dependent Claim
27 words
first comparison means operative to generate said first variable-width pulse whenever said rate of change of the rotational velocity of said selected wheel exceeds said predetermined threshold;
Claim 21
Dependent Claim
27 words
first comparison means operative to generate said first variable-width pulse whenever said rate of change of the rotational velocity of said selected wheel exceeds said predetermined threshold;
Claim 22
Dependent Claim
47 words
The system according to claim 1 wherein said second means comprises solenoid-actuated brake fluid pressure modulator means operative in response to said output to effect a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 23
Dependent Claim
23 words
A wheel slip control system for a vehicle having at least one wheel with an associated brake and an actuating mechanism therefor, comprising:
Claim 24
Dependent Claim
23 words
A wheel slip control system for a vehicle having at least one wheel with an associated brake and an actuating mechanism therefor, comprising:
Claim 25
Dependent Claim
61 words
reducing the braking force applied to at least said wheel during at least each period of slip time in which the reduction in wheel speed exceeds said variable reference increment of wheel speed, said reduction in wheel speed being measured from the value of wheel speed at the time the rate of change of wheel speed exceeds a first predetermined threshold.
Claim 26
Dependent Claim
61 words
reducing the braking force applied to at least said wheel during at least each period of slip time in which the reduction in wheel speed exceeds said variable reference increment of wheel speed, said reduction in wheel speed being measured from the value of wheel speed at the time the rate of change of wheel speed exceeds a first predetermined threshold.
Claim 27
Dependent Claim
59 words
variable reference signal generator means operative to receive said second signal and to generate a variable reference signal directly related to said second signal, the difference between the value of said first signal at the time of initiation of said first variable-width pulse and said variable reference signal being representative of said variable reference increment of wheel speed; and
Claim 28
Dependent Claim
59 words
variable reference signal generator means operative to receive said second signal and to generate a variable reference signal directly related to said second signal, the difference between the value of said first signal at the time of initiation of said first variable-width pulse and said variable reference signal being representative of said variable reference increment of wheel speed; and
Claim 29
Dependent Claim
58 words
second comparison means operative to receive said variable reference signal and to receive said first signal after initiation of said first variable-width pulse, and to generate a second variable-width pulse whenever the difference between said first signal and its value at the time of initiation of said first variable-width pulse exceeds said variable reference increment of wheel speed.
Claim 30
Dependent Claim
58 words
second comparison means operative to receive said variable reference signal and to receive said first signal after initiation of said first variable-width pulse, and to generate a second variable-width pulse whenever the difference between said first signal and its value at the time of initiation of said first variable-width pulse exceeds said variable reference increment of wheel speed.
Claim 31
Dependent Claim
11 words
The system according to claim 3 wherein said first means comprises:
Claim 32
Dependent Claim
39 words
The system according to claim 5 wherein said first means further comprises low speed detector means operative, whenever said rotational velocity of said selected wheel falls below a predetermined minimum speed, to prevent generation of said first variable-width pulse.
Claim 33
Dependent Claim
39 words
The system according to claim 5 wherein said second comparison means comprises gating circuit means operative in response to at least the initiation of said first variable-width pulse to enable said second comparison means to initiate its comparison function.
Claim 34
Dependent Claim
12 words
The system according to claim 7 wherein said first means further comprises:
Claim 35
Dependent Claim
12 words
The system according to claim 8 wherein said first means further comprises:
Claim 36
Dependent Claim
24 words
The system according to claim 9 wherein said second logic means comprises an OR gate, and said third logic means comprises an AND gate.
Claim 37
Dependent Claim
27 words
The system according to claim 9 wherein said first means further comprises power amplifier means operative to receive and amplify the output from said second logic means.
Claim 38
Dependent Claim
52 words
The system according to claim 9 wherein said second means comprises solenoid-actuated brake fluid pressure modulator means operative in response to the output of said second logic means to effect a decrease in the brake fluid pressure applied to at least the actuating mechanism of the brake associated with said selected wheel.
Claim 39
Independent Claim
20 words
A method of controlling the degree of slip of at least one breakeable vehicle wheel, comprising essentially the steps of:
Claim 40
Independent Claim
20 words
A method of controlling the degree of slip of at least one breakeable vehicle wheel, comprising essentially the steps of:
Claim 41
Dependent Claim
48 words
The method according to claim 13 comprising the additional step of extending the period of reduction of braking force whenever both (1) said period of slip time exceeds a predetermined value and (2) the rate of change of the speed of said wheel exceeds a second predetermined threshold.
Claim 42
Dependent Claim
56 words
The method according to claim 13 wherein said step of reducing braking force during at least said periods of slip time is performed continuously after the rate of change of wheel speed first exceeds said predetermined threshold as a result of the application of braking force until a predetermined low value of wheel speed is reached.
Claim 43
Dependent Claim
18 words
The method according to claim 13 wherein the monitored vehicle wheel is the wheel having the lowest velocity.
Claim 44
Dependent Claim
37 words
The method according to claim 13 wherein said step of reducing braking force comprises the step of initiating the reduction of braking force after said reduction in wheel speed exceeds said variable reference increment of wheel speed.
Claim 45
Dependent Claim
66 words
The method according to claim 13 wherein said step of reducing braking force comprises the step of terminating the reduction of braking force after the wheel speed increases to a value which does not differ from the value of wheel speed at the time the rate of change of wheel speed exceeded said first predetermined threshold by more than said variable reference increment of wheel speed.
Claim 46
Dependent Claim
70 words
The method according to claim 13 wherein said step of reducing braking force comprises the step of terminating the reduction of braking force after boTh (1) said period of slip time has exceeded a predetermined value and (2) the rate of change of the speed of said wheel has fallen below a second predetermined threshold which was exceeded at the time said period of slip time exceeded said predetermined 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) | 1977-09-02 | 1978-03-04 | 1978-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-02 | 1982-03-04 | 1982-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-02 | 1986-03-04 | 1986-09-03 | $7700.00 | Window Closed / Lapsed |