US4309060A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-locking wheel control system
Assignee: Robert Bosch GmbH
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Filing: 1978-10-18
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Granted: 1982-01-05
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Expires: 1998-10-18
Abstract
Abstract The invention relates to an anti-locking wheel control system in which control signals for the variation of the brake pressure are derived from the rotary motion behavior of the vehicle wheels and in which a test circuit is provided, which initiates a test for at least one wheel brake when a signal appears which indicates a tendency toward locking, in which test the over-braked vehicle wheel enters a state of high slippage, whereby the test circuit determines how the wheel behaves at the given coefficient of friction between the road surfaces and the tire, and whereby on the basis of this determination, the test circuit either provides a state in which the brake pressure is regulated or else switches to a state in which the control is made ineffective for at least some of the wheel brakes.
Inventors
- 👤 Heinz Leiber
- 👤 Volker Braschel
- 👤 Wolf-Dieter Jonner
- 👤 Hans-Herbert Wupper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:40
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/176; B60T8/1763; B60T8/17636; B60T2210/00; B60T2210/10; B60T2210/16
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
208 words
An anti-locking wheel control system in which control signals for the variation of the brake pressure are derived from the rotary motion behavior of the vehicle wheels and in which a test circuit is provided, which initiates a test for at least one wheel brake when a signal appears which indicates a tendency toward locking, in which test the over-braked vehicle wheel enters a state of high slippage, whereby the test circuit determines how the wheel behaves at a given coefficient of friction between road surface and tire, and whereby on the basis of this determination, the test circuit either permits the state in which the brake pressure is regulated or else switches on the state in which the control system is made ineffective for at least some of the wheel brakes, characterized by means incorporated in said test circuit for maintaining the brake pressure substantially constant during the test and by means for determining by monitoring at least one wheel during the deceleration phase, whether the vehicle wheel is running on a base with a coefficient of friction μ, where the μ-slippage curve rises with increasing slippage above a predetermined slippage value whereby the control system is made ineffective if such a coefficient of friction is determined.
Claim 2
Dependent Claim
208 words
An anti-locking wheel control system in which control signals for the variation of the brake pressure are derived from the rotary motion behavior of the vehicle wheels and in which a test circuit is provided, which initiates a test for at least one wheel brake when a signal appears which indicates a tendency toward locking, in which test the over-braked vehicle wheel enters a state of high slippage, whereby the test circuit determines how the wheel behaves at a given coefficient of friction between road surface and tire, and whereby on the basis of this determination, the test circuit either permits the state in which the brake pressure is regulated or else switches on the state in which the control system is made ineffective for at least some of the wheel brakes, characterized by means incorporated in said test circuit for maintaining the brake pressure substantially constant during the test and by means for determining by monitoring at least one wheel during the deceleration phase, whether the vehicle wheel is running on a base with a coefficient of friction μ, where the μ-slippage curve rises with increasing slippage above a predetermined slippage value whereby the control system is made ineffective if such a coefficient of friction is determined.
Claim 3
Dependent Claim
28 words
An anti-locking wheel control system in accordance with claim 1 wherein said test circuit includes means for determining whether the wheel enters a velocity which varies from zero.
Claim 4
Dependent Claim
30 words
An anti-locking wheel control system in accordance with claim 2 wherein said test circuit includes means for determining whether a slippage signal is present at least at one given time.
Claim 5
Dependent Claim
32 words
An anti-locking wheel control system in accordance with claim 3 wherein the slippage signal is processed only if in said given time the wheel velocity is higher than a given low velocity.
Claim 6
Dependent Claim
65 words
An anti-locking wheel control system in accordance with claim 1 wherein said test circuit includes means for determining whether the vehicle wheel undergoes a deceleration of a given amount by the time it attains a low wheel velocity v min , whereby the control system is made ineffective if the deceleration drops below the given amount before said low wheel velocity v min is reached.
Claim 7
Dependent Claim
33 words
An anti-locking wheel control system in accordance with claim 1, including means for initiating a new test if a given amount of time has elapsed after the control system has been made ineffective.
Claim 8
Dependent Claim
22 words
An anti-locking wheel control system in accordance with claim 1, characterized in that only the front wheels are included in the test.
Claim 9
Dependent Claim
24 words
An anti-locking wheel control system in accordance with claim 7, characterized in that the test takes place simultaneously for both of said front wheels.
Claim 10
Dependent Claim
35 words
An anti-locking wheel control system in accordance with claim 8, characterized in that said control system is made ineffective by said test circuit only if the switchover criteria are determined for at least two wheels.
Claim 11
Dependent Claim
32 words
An anti-locking wheel control system in accordance with claim 9, characterized in that the test is initiated by said test circuitry only if the vehicle velocity is lower than a given value.
Claim 12
Dependent Claim
30 words
An anti-locking wheel control system in accordance with claim 10, including means for precluding the test by said test circuit if the longitudinal deceleration is larger than approximately 0.5 g.
Claim 13
Dependent Claim
51 words
An anti-locking wheel control system in accordance with claim 11, characterized in that when a switchoff signal appears, the control system for controlling the brakes of the front axle is made alternatively effective and ineffective and that the control system for controlling the brakes of the rear axle is continuously effective.
Claim 14
Dependent Claim
66 words
An anti-locking wheel control system in accordance with claim 12, including switching means for determining subsequent to the initiation of the test by said test circuit whether, over a given time period, the wheel slippage exceeds a given value λ T for a given time period and said switching means being adapted to allow the test to continue for utilization of the results of the test.
Claim 15
Dependent Claim
39 words
An anti-locking wheel control system in accordance with claim 13, characterized in that said test is first initiated by said test circuit at least at the second appearance of the signal indicating the tendency of the wheel to lock.
Claim 16
Dependent Claim
33 words
An anti-locking wheel control system in accordance with claim 8, including means for periodically changing the brake pressure for at least some of the wheels when the control system has been made ineffective.
Claim 17
Dependent Claim
23 words
An anti-locking wheel control system in accordance with claim 15, characterized in that the brake pressure of the rear wheels is periodically changed.
Claim 18
Dependent Claim
32 words
An anti-locking wheel control system in accordance with claim 15, characterized in that the pressure at the front wheels is periodically changed and the control at the rear axle wheels is maintained.
Claim 19
Dependent Claim
184 words
An anti-locking wheel control system in which control signals for the variation of the brake pressure are derived from the rotary motion behavior of the vehicle wheels and in which a test circuit is provided which initiates a test for at least one wheel brake when a signal appears which indicates a tendency toward locking, in which test the over-braked vehicle wheel enters a state of high slippage, whereby the test circuit determines how the wheel behaves at a given coefficient of friction between road surface and tire, and whereby on the basis of this determination the test circuit either permits the state in which the brake pressure is regulated or else switches on the state in which the control is made ineffective for at least some of the wheel brakes, characterized by means incorporated in said test circuit for maintaining the the brake pressure substantially constant during the test and means in said test circuit for making the control system ineffective, if a signal indicating a reduction of slippage appears after the wheel velocity has dropped below a low velocity v min .
Claim 20
Dependent Claim
184 words
An anti-locking wheel control system in which control signals for the variation of the brake pressure are derived from the rotary motion behavior of the vehicle wheels and in which a test circuit is provided which initiates a test for at least one wheel brake when a signal appears which indicates a tendency toward locking, in which test the over-braked vehicle wheel enters a state of high slippage, whereby the test circuit determines how the wheel behaves at a given coefficient of friction between road surface and tire, and whereby on the basis of this determination the test circuit either permits the state in which the brake pressure is regulated or else switches on the state in which the control is made ineffective for at least some of the wheel brakes, characterized by means incorporated in said test circuit for maintaining the the brake pressure substantially constant during the test and means in said test circuit for making the control system ineffective, if a signal indicating a reduction of slippage appears after the wheel velocity has dropped below a low velocity v min .
Claim 21
Dependent Claim
31 words
An anti-locking wheel control system in accordance with claim 18, including means for making the control system ineffective if the signal indicating the reduction of slippage has made a multiple appearance.
Claim 22
Dependent Claim
23 words
An anti-locking wheel control system in accordance with claim 18, characterized in that the signal indicating the slippage reduction is an acceleration signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-01-04 | 1985-07-06 | 1986-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-04 | 1989-07-06 | 1990-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-04 | 1993-07-06 | 1994-01-05 | $7700.00 | Window Closed / Lapsed |