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US4788644A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for controlling an acceleration slip of a vehicle

Assignee: Toyota Motor Corp
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Filing: 1987-04-23
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Granted: 1988-11-29
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Expires: 2007-04-23
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Abstract

Abstract An acceleration slip control method quickly terminate an acceleration slip control when it is no longer necessary. A quick detection of the termination adopts, as terminating conditions, a preset time duration of reduction of drive wheel brake force and reduction of the drive wheel slip rate. The quick termination of the acceleration slip control enables immediate voluntary acceleration and better maneuverability of the vehicle.

Inventors

  • 👤 Takafumi Inagaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 06:24
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/175

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 163 words
A method for controlling a slip between a drive wheel of a vehicle and a road surface during acceleration, comprising the steps of: detecting a slip rate of the drive wheel; determining whether the detected slip rate is greater than a first preset value; starting a slip control for reducing the slip rate when the detected slip rate is determined to be greater than the first preset value, the slip control including at least actuating a brake system of the drive wheel; determining whether a brake force is less than a predetermined value; determining whether the detected slip rate is less than a second preset value after said brake system is actuated, the second preset value being less than the first preset value; and terminating the slip control after a preset time period during which the detected brake force is determined to be less than the predetermined value and the detected slip rate is determined to be less than the second preset value.
Claim 2
Independent Claim 163 words
A method for controlling a slip between a drive wheel of a vehicle and a road surface during acceleration, comprising the steps of: detecting a slip rate of the drive wheel; determining whether the detected slip rate is greater than a first preset value; starting a slip control for reducing the slip rate when the detected slip rate is determined to be greater than the first preset value, the slip control including at least actuating a brake system of the drive wheel; determining whether a brake force is less than a predetermined value; determining whether the detected slip rate is less than a second preset value after said brake system is actuated, the second preset value being less than the first preset value; and terminating the slip control after a preset time period during which the detected brake force is determined to be less than the predetermined value and the detected slip rate is determined to be less than the second preset value.
Claim 3
Dependent Claim 29 words
The accleration slip control method as claimed in claim 1, wherein the slip control further includes the step of reducing an output power of the engine of the vehicle.
Claim 4
Dependent Claim 49 words
The acceleration slip control method as claimed in claim 2, wherein the engine output power reducing step comprises the step of closing a secondary throttle valve provided in an intake pipe of the engine in series with a main throttle valve which is controlled by the accelerator pedal operation.
Claim 5
Dependent Claim 59 words
The acceleration slip control method as claimed in claim 3, wherein the brake system of the drive wheel is operated by hydraulic pressure whose pressure source is provided separately from an ordingary brake system actuated by a driver's brake operation, and wherein said brake force determining step comprises the step of determining the hydraulic pressure in said brake system.
Claim 6
Dependent Claim 17 words
The acceleration slip control method as claimed in claim 4, wherein the predetermined value is substantially zero.
Claim 7
Dependent Claim 38 words
The acceleration slip control method as claimed in claim 5, including the step of setting the first preset value at a value at which the dynamic friction force between the drive wheel and the road surface is greatest.
Claim 8
Dependent Claim 42 words
The acceleration slip control method as claimed in claim 6, including the step of setting the time period at a value slightly longer than a cycle time of the rotation speed fluctuation of the drive wheel arising due to the slip control.
Claim 9
Dependent Claim 167 words
A slip controller for a vehicle for controlling a slip between a drive wheel of the vehicle and a road surface during acceleration, comprising: means for detecting a slip rate of the drive wheel; means for determining whether the detected slip rate is greater than a first preset value; a drive wheel brake system; means for detecting the brake force of the drive wheel; means for determining whether the detected brake force is less than a predetermined value; and control means for starting a slip control for reducing slip rate when the detected slip rate is determined to be greater than the first preset value, using at least the brake system of the drive wheel, and for terminating the slip control after a preset time period during which the detected brake force is determined to be less than the predetermined value and the detected slip rate is determined to be less than a second preset value, the second preset value being less than the first preset value.
Claim 10
Dependent Claim 167 words
A slip controller for a vehicle for controlling a slip between a drive wheel of the vehicle and a road surface during acceleration, comprising: means for detecting a slip rate of the drive wheel; means for determining whether the detected slip rate is greater than a first preset value; a drive wheel brake system; means for detecting the brake force of the drive wheel; means for determining whether the detected brake force is less than a predetermined value; and control means for starting a slip control for reducing slip rate when the detected slip rate is determined to be greater than the first preset value, using at least the brake system of the drive wheel, and for terminating the slip control after a preset time period during which the detected brake force is determined to be less than the predetermined value and the detected slip rate is determined to be less than a second preset value, the second preset value being less than the first preset value.

References Cited (Backward Citations)

US4361871A Cited
US4530059A Cited
US4648663A Cited
US4681374A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-11-29 1992-05-30 1992-11-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-11-29 1996-05-30 1996-11-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-11-29 2000-05-30 2000-11-29 $7700.00 Window Closed / Lapsed

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