US3718374A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Skid control system for automotive vehicles
Assignee: Toyota Motor Corp
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Filing: 1970-06-30
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Granted: 1973-02-27
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Expires: 1990-06-30
Abstract
Abstract A skid control system for automotive vehicles having hydraulic brakes includes a wheel speed detector and a memory circuit connected to the detector to store the initial speed of the vehicle at the start of braking. A pressure detecting means is connected to the brake system to detect the fluid pressure during brake application, and a function generator converts the detected pressure into an arbitary function proportional thereto, and which is integrated. The integrated function is compared to the stored initial speed of the vehicle to derive a difference value which is amplified and supplied to a comparator connected to the wheel speed detector to provide a control signal. This control signal operates a servo mechanism to control the braking system in accordance with the control signal.
Inventors
- 👤 T Ochia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:51
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/176; B60T8/1761; B60T8/17613; Y; Y10; Y10S; Y10S303/00; Y10S303/02; Y10S303/03; Y10S303/04
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
242 words
An automotive vehicle skid control system for a vehicle having plural wheels including front wheels and rear wheels, with at least one wheel being controlled, comprising, in combination, fluid pressure operated wheel brake applying means; speed detecting means operable to detect the speed of at least one wheel of the vehicle; memory means operatively connected to said speed detecting means to store the initial speed of the vehicle at the start of brake application; pressure detecting means connected to said brake applying means to detect the fluid pressure during brake application; non-linear function generating means connected to said pressure detecting means and operable to convert the value of the detected fluid pressure into a nonlinear functional value related to deceleration; integrating means connected to said function generating means; deriving means connected to said memory means and to said integrating means and deriving the difference between said initial speed and the integrated value; amplifying means connected to said deriving means and operable to multiply the output of said deriving means by a factor dependent upon the slip of the wheel on a road surface; comparator means connected to said amplifying means and to said detecting means and operable to compare the output of said amplifying means with that of said speed detecting means; and servo mechanism connected to said comparator means and to said brake applying means and operable to control operation of the latter in accordance with the output of said comparator.
Claim 2
Dependent Claim
242 words
An automotive vehicle skid control system for a vehicle having plural wheels including front wheels and rear wheels, with at least one wheel being controlled, comprising, in combination, fluid pressure operated wheel brake applying means; speed detecting means operable to detect the speed of at least one wheel of the vehicle; memory means operatively connected to said speed detecting means to store the initial speed of the vehicle at the start of brake application; pressure detecting means connected to said brake applying means to detect the fluid pressure during brake application; non-linear function generating means connected to said pressure detecting means and operable to convert the value of the detected fluid pressure into a nonlinear functional value related to deceleration; integrating means connected to said function generating means; deriving means connected to said memory means and to said integrating means and deriving the difference between said initial speed and the integrated value; amplifying means connected to said deriving means and operable to multiply the output of said deriving means by a factor dependent upon the slip of the wheel on a road surface; comparator means connected to said amplifying means and to said detecting means and operable to compare the output of said amplifying means with that of said speed detecting means; and servo mechanism connected to said comparator means and to said brake applying means and operable to control operation of the latter in accordance with the output of said comparator.
Claim 3
Dependent Claim
29 words
An automotive vehicle skid control system, as claimed in claim 1, in which said deriving means comprises a subtractor connected to said memory means and to said integrating means.
Claim 4
Dependent Claim
124 words
An automotive vehicle skid control system, as claimed in claim 1, in which said function generating means has an input terminal, an output terminal and a third terminal; plural diodes having their anodes connected to said input terminal through respective resistances of different ohmic values; a first amplifier having a negative input terminal commonly connected to the cathodes of said diodes; respective resistances, of different ohmic values, connected to said thIrd terminal and biasing said diodes in the reverse direction; said first amplifier having a grounded positive input terminal; a feedback resistance connecting the output terminal of said first amplifier to its negative input terminal; and means connecting the output terminal of said first amplifier to the output terminal of said function generating means.
Claim 5
Dependent Claim
81 words
An automotive vehicle skid control system, as claimed in claim 3, in which said last named means comprises a second amplifier having a negative input terminal connected to the output terminal of said first amplifier through a resistance, and having a grounded input terminal; means connecting the output terminal of said second amplifier to the output terminal of said function generating means; and a second feedback resistance connecting the output terminal of said second amplifier to the negative input terminal thereof.
Claim 6
Dependent Claim
34 words
An automotive vehicle skid control system, as claimed in claim 4, in which the characteristic curve of said function generating means comprises a series of interconnected straight lines extending at angles to each other.
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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) | 1976-02-27 | 1976-08-28 | 1977-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-27 | 1980-08-28 | 1981-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-27 | 1984-08-28 | 1985-02-27 | $7700.00 | Window Closed / Lapsed |