Patent US1560441A successfully refreshed from Google Patents.
Patent US3877758A successfully refreshed from Google Patents.
US3877758A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the control of an antiskid braking system and apparatus adapted for performing the same
Assignee: Aisin Corp
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Filing: 1973-06-29
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Granted: 1975-04-15
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Expires: 1993-06-29
Abstract
Abstract This invention presents an improved antiskid brake control method and apparatus for wheeled automotive vehicles which utilizes an electronic circuit into which input signals representing vehicle speed, wheel speed and hydraulic brake apply pressure are fed. The electronic control circuit computes the rate of vehicle deceleration and the ratio of the wheel speed to the vehicle speed and compares this ratio with a constant value. An output signal from the electronic circuit is used to control an electric solenoid valve in the hydraulic brake circuit to modulate the hydraulic pressure and obtain an optimum vehicle braking effort under all conditions and prevent a vehicle skid condition from arising.
Inventors
- 👤 Kazutaka Kuwana
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:30
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/176; B60T8/1763; B60T8/17633; B60T8/32; B60T8/34; B60T8/50; B60T8/5018; B60T8/5025; B60T8/5037; B60T8/5043; B60T8/5087; B60T8/5093
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
278 words
Apparatus for anti-skid brake control, comprising in combination, a master cylinder, a wheel cylinder, passage means for hydraulic connection between said master cylinder and said wheel cylinder, said sensor means including means for sensing a wheel lock condition during a braking operation and for delivering a first signal upon sensing said lock condition and for sensing wheel lock recovery condition for delivering a second signal upon sensing said recovery condition, and further including means for sensing magnitudes of said wheel lock condition and wheel lock recovery condition, cut-off valve means provided in said passage means for on-off control of said passage means, volume increase and reduction means for increasing and decreasing the volume of said passage means leading from said valve means to said wheel cylinder, servo means operatively connected to said valve means and said volume increase and reduction means, said servo means including cylinder and piston means having two separate chambers within said servo means on opposite sides of said piston means, an air change-over valve means operable in response to said two signals from said sensor means and for establishment of an air pressure differential between said two chambers, and control valve means operable in response to said wheel lock condition and said wheel lock recovery condition sensed by said sensor means, said control valve means being operably connected to one of said chambers for varying the rate of air delivery to said servo means in response to operation of said air change-over valve means, whereby the rate of reduction in and restoration of the wheel cylinder brake pressure is controlled in response to the magnitudes of said wheel lock and wheel lock recovery conditions.
Claim 2
Dependent Claim
278 words
Apparatus for anti-skid brake control, comprising in combination, a master cylinder, a wheel cylinder, passage means for hydraulic connection between said master cylinder and said wheel cylinder, said sensor means including means for sensing a wheel lock condition during a braking operation and for delivering a first signal upon sensing said lock condition and for sensing wheel lock recovery condition for delivering a second signal upon sensing said recovery condition, and further including means for sensing magnitudes of said wheel lock condition and wheel lock recovery condition, cut-off valve means provided in said passage means for on-off control of said passage means, volume increase and reduction means for increasing and decreasing the volume of said passage means leading from said valve means to said wheel cylinder, servo means operatively connected to said valve means and said volume increase and reduction means, said servo means including cylinder and piston means having two separate chambers within said servo means on opposite sides of said piston means, an air change-over valve means operable in response to said two signals from said sensor means and for establishment of an air pressure differential between said two chambers, and control valve means operable in response to said wheel lock condition and said wheel lock recovery condition sensed by said sensor means, said control valve means being operably connected to one of said chambers for varying the rate of air delivery to said servo means in response to operation of said air change-over valve means, whereby the rate of reduction in and restoration of the wheel cylinder brake pressure is controlled in response to the magnitudes of said wheel lock and wheel lock recovery conditions.
Claim 3
Dependent Claim
55 words
Apparatus as set forth in claim 1 wherein said air change-over valve means has a first position wherein vacuum is conveyed to said two chambers in said servo means upon reception of said second signal, and a second position wherein air is introduced into one of said two chambers upon reception of said first signal.
Claim 4
Dependent Claim
39 words
Apparatus as set forth in claim 2 wherein said control valve means limits the air flow rate to and from one of said two chambers in response to said wheel lock condition and said wheel lock recovery condition, respectively.
Claim 5
Dependent Claim
275 words
Apparatus for anti-skid brake control, comprising in combination, a master cylinder, a wheel cylinder, passage means for hydraulic connection between said master cylinder and said wheel cylinder, skid sensor means including means for sensing a wheel lock condition during a braking operation and for delivering a first signal upon sensing said lock condition and for sensing wheel lock recovery condition for delivering a second signal upon sensing said recovery condition, and further including means for sensing magnitudes of said wheel lock condition and wheel lock recovery condition, cut-off valve means provided in said passage mEans for on-off control of said passage means, volume increase and reduction means for increasing and decreasing the volume of said passage means leading from said valve means to said wheel cylinder, servo means operatively connected to said valve means and said volume increase and reduction means, said servo means including cylinder and piston means having two separate chambers within said servo means on opposite sides of said piston means, change-over valve means operable in response to said two signals from said sensor means and for establishment of a fluid pressure differential between said two chambers, and control valve means operable in response to said wheel lock condition and said wheel lock recovery condition sensed by said sensor means, said control valve means being operably connected to one of said chambers for varying the rate of fluid delivery to said servo means in response to operation of said change-over valve means, whereby the rate of reduction in and restoration of the wheel cylinder brake pressure is controlled in response to the magnitudes of said wheel lock and wheel lock recovery conditions.
Claim 6
Dependent Claim
275 words
Apparatus for anti-skid brake control, comprising in combination, a master cylinder, a wheel cylinder, passage means for hydraulic connection between said master cylinder and said wheel cylinder, skid sensor means including means for sensing a wheel lock condition during a braking operation and for delivering a first signal upon sensing said lock condition and for sensing wheel lock recovery condition for delivering a second signal upon sensing said recovery condition, and further including means for sensing magnitudes of said wheel lock condition and wheel lock recovery condition, cut-off valve means provided in said passage mEans for on-off control of said passage means, volume increase and reduction means for increasing and decreasing the volume of said passage means leading from said valve means to said wheel cylinder, servo means operatively connected to said valve means and said volume increase and reduction means, said servo means including cylinder and piston means having two separate chambers within said servo means on opposite sides of said piston means, change-over valve means operable in response to said two signals from said sensor means and for establishment of a fluid pressure differential between said two chambers, and control valve means operable in response to said wheel lock condition and said wheel lock recovery condition sensed by said sensor means, said control valve means being operably connected to one of said chambers for varying the rate of fluid delivery to said servo means in response to operation of said change-over valve means, whereby the rate of reduction in and restoration of the wheel cylinder brake pressure is controlled in response to the magnitudes of said wheel lock and wheel lock recovery conditions.
Claim 7
Dependent Claim
119 words
Method for anti-skid brake control comprising: generating first, second, third, and fourth instruction signals in response to wheel rotational conditions, said first and second instruction signals being generated in response to wheel lock and wheel lock recovery, respectively, and said third and fourth instruction signals being generated in response to magnitudes of said wheel lock and wheel lock recovery, respectively, reducing wheel cylinder pressure upon reception of said first instruction signal, restoring the thus reduced wheel cylinder pressure upon reception of said second instruction signal, varying the rate of said wheel cylinder pressure reduction velocity upon reception of said third instruction signal, and varying the rate of said wheel cylinder pressure restoration upon reception of said fourth instruction signal.
Claim 8
Dependent Claim
119 words
Method for anti-skid brake control comprising: generating first, second, third, and fourth instruction signals in response to wheel rotational conditions, said first and second instruction signals being generated in response to wheel lock and wheel lock recovery, respectively, and said third and fourth instruction signals being generated in response to magnitudes of said wheel lock and wheel lock recovery, respectively, reducing wheel cylinder pressure upon reception of said first instruction signal, restoring the thus reduced wheel cylinder pressure upon reception of said second instruction signal, varying the rate of said wheel cylinder pressure reduction velocity upon reception of said third instruction signal, and varying the rate of said wheel cylinder pressure restoration upon reception of said fourth instruction 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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |