US5335178A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Slip control deceleration signal filtering system
Assignee: Robert Bosch GmbH
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Filing: 1990-03-30
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Granted: 1994-08-02
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Expires: 2010-03-30
Abstract
Abstract The invention relates to a method for filtering out disturbances in the form of short term wheel acceleration signals when the wheel exhibits an overall deceleration, so that a more accurate deceleration signal can be used for control of drive slippage. Wheel speed v is measured at intervals T A and speed changes for each interval are determined. When a change is negative or zero following a positive change in a previous interval, the wheel speed is stored as a maximum speed v max while v continues to be measured and a counter determines the period of time Δt between the occurrence of v max and the instantaneous value v. Beginning at a predetermined filtering time ΔT after storing v max , a quotient Δv/Δt representing the filtered slope of the value v is determined and used as a control variable to regulate wheel slippage.
Inventors
- 👤 Jochen Schafer
- 👤 Thomas Frank
- 👤 Frank Bederna
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:18
CPC Classifications
B; B60; B60L; B60L3/00; B60L3/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
141 words
Method for controlling wheel slippage in a vehicle comprising determining the speed of a driven wheel and producing an instantaneous digital wheel speed value v at time points displaced by measurement intervals T A , determining the speed change during each measurement interval T A , storing said value v as a maximum v max when said speed change is equal to or less than zero in a measurement interval T A immediately following an interval T A in which a speed change greater than zero was determined, determining a difference Δv =v max -v, determining a quotient Δv/Δt beginning at predetermined filtering time ΔT after storing v max , where At is elapsed time after storing v max said quotient representing a filtered slope of the value v, and using said quotient as a control variable to regulate wheel slippage.
Claim 2
Dependent Claim
141 words
Method for controlling wheel slippage in a vehicle comprising determining the speed of a driven wheel and producing an instantaneous digital wheel speed value v at time points displaced by measurement intervals T A , determining the speed change during each measurement interval T A , storing said value v as a maximum v max when said speed change is equal to or less than zero in a measurement interval T A immediately following an interval T A in which a speed change greater than zero was determined, determining a difference Δv =v max -v, determining a quotient Δv/Δt beginning at predetermined filtering time ΔT after storing v max , where At is elapsed time after storing v max said quotient representing a filtered slope of the value v, and using said quotient as a control variable to regulate wheel slippage.
Claim 3
Dependent Claim
32 words
Method as in claim 1 further comprising comparing said wheel speed value v to a threshold value and determining said quotient Δv/Δt only when said wheel speed value exceeds said threshold value.
Claim 4
Dependent Claim
30 words
Method as in claim 1 wherein said wheel speed signal exhibits a disturbance characterized by an expected period, said predetermined filtering time ΔT being greater than half the expected period.
Claim 5
Dependent Claim
26 words
Method as in claim 1 further comprising comparing said quotient Δv/Δt to a threshold value and producing an intervention signal when the threshold value is exceeded.
Claim 6
Dependent Claim
28 words
Method as in claim 1 further comprising comparing said period of time Δt to a threshold value and producing an intervention signal when the threshold value is exceeded.
Claim 7
Dependent Claim
30 words
Method as in claim 1 further comprising comparing said quotient Δv/Δt to a deceleration threshold value and erasing the stored value v max when said quotient exceeds a predetermined threshold.
Claim 8
Dependent Claim
38 words
Method as in claim 1 further comprising comparing said period of time Δt to a predetermined period of time and erasing the stored value v max when said period of time Δt exceeds said predetermined period of time.
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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) | 1997-08-01 | 1998-01-31 | 1998-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-01 | 2002-01-31 | 2002-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-01 | 2006-01-31 | 2006-08-02 | $7700.00 | Window Closed / Lapsed |