US5653516A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Antiskid control based on detected coefficient of friction
Assignee: Denso Corp
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Filing: 1995-06-07
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Granted: 1997-08-05
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Expires: 2015-06-07
Abstract
Abstract An antiskid control system executes a modified antiskid control which strengthens the tendency of the wheel to lock if a vehicle speed is under a predetermined speed and the vehicle is running on a road which has a low coefficient of friction. Antiskid control is also modified with respect to front wheels and is normal with respect to rear wheels in order to avoid an occurrence of vehicle spin. Further, antiskid control is modified with respect to either a front right wheel or a front left wheel. As a result, a stopping distance of the vehicle can be shortened while securing the steering stability of the vehicle.
Inventors
- 👤 Masahiko Taniguchi
- 👤 Kazuya Maki
- 👤 Takashi Watanabe
- 👤 Junji Mizutani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:00
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/176; B60T8/1763; B60T8/17636
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
159 words
An antiskid control system of a vehicle including antiskid condition determining means for determining whether or not each wheel reaches an antiskid control condition at which antiskid control is performed during a brake operation, and antiskid controlling means for controlling a deceleration state of a wheel determined to reach the antiskid control condition by adjusting a brake fluid pressure of the wheel, comprising: determining means for determining whether or not the vehicle is running on a low friction road which has a low coefficient of friction; and control mode changing means for changing a control mode of said antiskid controlling means to a mode which strengthens a locking tendency of at least one wheel when the vehicle is running on the low friction road, wherein said antiskid controlling means executes the antiskid control according to an unchanged control mode when the vehicle is running on the road which has a friction coefficient greater than said low coefficient of friction.
Claim 2
Dependent Claim
159 words
An antiskid control system of a vehicle including antiskid condition determining means for determining whether or not each wheel reaches an antiskid control condition at which antiskid control is performed during a brake operation, and antiskid controlling means for controlling a deceleration state of a wheel determined to reach the antiskid control condition by adjusting a brake fluid pressure of the wheel, comprising: determining means for determining whether or not the vehicle is running on a low friction road which has a low coefficient of friction; and control mode changing means for changing a control mode of said antiskid controlling means to a mode which strengthens a locking tendency of at least one wheel when the vehicle is running on the low friction road, wherein said antiskid controlling means executes the antiskid control according to an unchanged control mode when the vehicle is running on the road which has a friction coefficient greater than said low coefficient of friction.
Claim 3
Dependent Claim
38 words
An antiskid control system according to claim 1, further comprising speed limiting means for allowing the operation of said control mode changing means only when a vehicle running speed is equal to or lower than a predetermined speed.
Claim 4
Dependent Claim
22 words
An antiskid control system according to claim 1, wherein said control mode changing means changes the control mode of only front wheels.
Claim 5
Dependent Claim
48 words
An antiskid control system according to claim 3, wherein said control mode changing means changes the control modes so that the locking tendency of either one of a front left wheel and a front right wheel is strengthened and the locking tendency of another front wheel remains unstrengthened.
Claim 6
Dependent Claim
36 words
An antiskid control system according to claim 4, wherein said control mode changing means changes the control modes so that the locking tendencies of the front left wheel and the front right wheel are strengthened sequentially.
Claim 7
Dependent Claim
42 words
An antiskid control system according to claim 1, wherein the control mode is changed in a manner that the locking tendency is strengthened by increasing the brake fluid pressure when the brake fluid pressure should be reduced in a normal control mode.
Claim 8
Dependent Claim
22 words
An antiskid control system according to claim 6, wherein the increase of the brake fluid pressure is performed in a pulsed manner.
Claim 9
Dependent Claim
29 words
An antiskid control system according to claim 1, wherein said control mode changing means changes the control modes so that the locking tendency of the wheel is gradually strengthened.
Claim 10
Dependent Claim
69 words
An antiskid control system according to claim 8, wherein said control mode changing means changes the control modes so that the locking tendency of the wheel is gradually strengthened by gradually lengthening a pressure increase period of time in the case where the locking tendency of the wheel is strengthened by increasing the brake fluid pressure when the brake fluid pressure should be reduced in a normal control mode.
Claim 11
Dependent Claim
42 words
An antiskid control system according to claim 1, wherein said control mode changing means changes the control modes so that the locking tendency is strengthened as a result that said antiskid controlling means raises a target slip ratio of the antiskid control.
Claim 12
Dependent Claim
23 words
An antiskid control system according to claim 10, wherein said antiskid controlling means gradually raises the target slip ratio of the antiskid control.
Claim 13
Dependent Claim
49 words
An antiskid control system according to claim 1, wherein said control mode changing means changes the control modes by adjusting the brake fluid pressure of a wheel having a stronger locking tendency so as to be equal to the brake pressure of a wheel having a weaker locking tendency.
Claim 14
Dependent Claim
126 words
An antiskid control system for a vehicle including antiskid condition determining means for determining whether or not each wheel reaches an antiskid control condition to perform an antiskid control during a brake operation, and antiskid controlling means for controlling a deceleration state of a wheel determined to reach the antiskid control condition by adjusting a brake fluid pressure of the wheel, comprising: measuring means for measuring a period of time that said antiskid controlling means adjusts the brake fluid pressure of the wheel; control mode changing means for changing a control mode of said antiskid controlling means to a mode which strengthens a locking tendency of at least one wheel when the period of time measured by said measuring means exceeds a predetermined period of time.
Claim 15
Dependent Claim
126 words
An antiskid control system for a vehicle including antiskid condition determining means for determining whether or not each wheel reaches an antiskid control condition to perform an antiskid control during a brake operation, and antiskid controlling means for controlling a deceleration state of a wheel determined to reach the antiskid control condition by adjusting a brake fluid pressure of the wheel, comprising: measuring means for measuring a period of time that said antiskid controlling means adjusts the brake fluid pressure of the wheel; control mode changing means for changing a control mode of said antiskid controlling means to a mode which strengthens a locking tendency of at least one wheel when the period of time measured by said measuring means exceeds a predetermined period of time.
Claim 16
Dependent Claim
38 words
An antiskid control system according to claim 13, further comprising speed limiting means for allowing the operation of said control mode changing means only when a vehicle running speed is equal to or lower than a predetermined speed.
Claim 17
Dependent Claim
22 words
An antiskid control system according to claim 13, wherein said control mode changing means changes the control mode of only front wheels.
Claim 18
Dependent Claim
48 words
An antiskid control system according to claim 15, wherein said control mode changing means changes the control modes so that the locking tendency of either one of a front left wheel and a front right wheel is strengthened and the locking tendency of another front wheel remains unstrengthened.
Claim 19
Dependent Claim
36 words
An antiskid control system according to claim 16, wherein said control mode changing means changes the control modes so that the locking tendencies of the front left wheel and the front right wheel are strengthened sequentially.
Claim 20
Dependent Claim
42 words
An antiskid control system according to claim 13, wherein the control mode is changed in a manner that the locking tendency is strengthened by increasing the brake fluid pressure when the brake fluid pressure should be reduced in a normal control mode.
Claim 21
Dependent Claim
22 words
An antiskid control system according to claim 18, wherein the increase of the brake fluid pressure is performed in a pulsed manner.
Claim 22
Dependent Claim
29 words
An antiskid control system according to claim 13, wherein said control mode changing means changes the control modes so that the locking tendency of the wheel is gradually strengthened.
Claim 23
Dependent Claim
69 words
An antiskid control system according to claim 20, wherein said control mode changing means changes the control modes so that the locking tendency of the wheel is gradually strengthened by gradually lengthening a pressure increase period of time in the case where the locking tendency of the wheel is strengthened by increasing the brake fluid pressure when the brake fluid pressure should be reduced in a normal control mode.
Claim 24
Dependent Claim
42 words
An antiskid control system according to claim 13, wherein said control mode changing means changes the control modes so that the locking tendency is strengthened as a result that said antiskid controlling means raises a target slip ratio of the antiskid control.
Claim 25
Dependent Claim
23 words
An antiskid control system according to claim 22, wherein said antiskid controlling means gradually raises the target slip ratio of the antiskid control.
Claim 26
Dependent Claim
49 words
An antiskid control system according to claim 13, wherein said control mode changing means changes the control modes by adjusting the brake fluid pressure of a wheel having a stronger locking tendency so as to be equal to the brake pressure of a wheel having a weaker locking tendency.
Claim 27
Dependent Claim
131 words
An antiskid control system for a vehicle including antiskid condition determining means for determining whether or not each wheel reaches an antiskid control condition to perform an antiskid control during a brake operation, and antiskid controlling means for controlling a deceleration state of a wheel determined to reach the antiskid control condition by adjusting a brake fluid pressure of the wheel, comprising: counting means for counting a number of times that said antiskid controlling means executes control cycle including a brake pressure increase and a brake pressure reduction; control mode changing means for changing a control mode of said antiskid controlling means to a mode which strengthens a locking tendency of at least one wheel when the number of times counted by said counting means exceeds a predetermined number of times.
Claim 28
Dependent Claim
131 words
An antiskid control system for a vehicle including antiskid condition determining means for determining whether or not each wheel reaches an antiskid control condition to perform an antiskid control during a brake operation, and antiskid controlling means for controlling a deceleration state of a wheel determined to reach the antiskid control condition by adjusting a brake fluid pressure of the wheel, comprising: counting means for counting a number of times that said antiskid controlling means executes control cycle including a brake pressure increase and a brake pressure reduction; control mode changing means for changing a control mode of said antiskid controlling means to a mode which strengthens a locking tendency of at least one wheel when the number of times counted by said counting means exceeds a predetermined number of times.
Claim 29
Dependent Claim
38 words
An antiskid control system according to claim 25, further comprising speed limiting means for allowing the operation of said control mode changing means only when a vehicle running speed is equal to or lower than a predetermined speed.
Claim 30
Dependent Claim
22 words
An antiskid control system according to claim 25, wherein said control mode changing means changes the control mode of only front wheels.
Claim 31
Dependent Claim
48 words
An antiskid control system according to claim 27, wherein said control mode changing means changes the control modes so that the locking tendency of either one of a front left wheel and a front right wheel is strengthened and the locking tendency of another front wheel remains unstrengthened.
Claim 32
Dependent Claim
36 words
An antiskid control system according to claim 28, wherein said control mode changing means changes the control modes so that the locking tendencies of the front left wheel and the front right wheel are strengthened sequentially.
Claim 33
Dependent Claim
42 words
An antiskid control system according to claim 25, wherein the control mode is changed in a manner that the locking tendency is strengthened by increasing the brake fluid pressure when the brake fluid pressure should be reduced in a normal control mode.
Claim 34
Dependent Claim
22 words
An antiskid control system according to claim 30, wherein the increase of the brake fluid pressure is performed in a pulsed manner.
Claim 35
Dependent Claim
29 words
An antiskid control system according to claim 25, wherein said control mode changing means changes the control modes so that the locking tendency of the wheel is gradually strengthened.
Claim 36
Dependent Claim
69 words
An antiskid control system according to claim 32, wherein said control mode changing means changes the control modes so that the locking tendency of the wheel is gradually strengthened by gradually lengthening a pressure increase period of time in the case where the locking tendency of the wheel is strengthened by increasing the brake fluid pressure when the brake fluid pressure should be reduced in a normal control mode.
Claim 37
Dependent Claim
42 words
An antiskid control system according to claim 25, wherein said control mode changing means changes the control modes so that the locking tendency is strengthened as a result that said antiskid controlling means raises a target slip ratio of the antiskid control.
Claim 38
Dependent Claim
23 words
An antiskid control system according to claim 34, wherein said antiskid controlling means gradually raises the target slip ratio of the antiskid control.
Claim 39
Dependent Claim
49 words
An antiskid control system according to claim 25, wherein said control mode changing means changes the control modes by adjusting the brake fluid pressure of a wheel having a stronger locking tendency so as to be equal to the brake pressure of a wheel having a weaker locking tendency.
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) | 2000-08-04 | 2001-02-03 | 2001-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-08-04 | 2005-02-03 | 2005-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-08-04 | 2009-02-03 | 2009-08-05 | $7700.00 | Window Closed / Lapsed |