Patent US3790224A successfully refreshed from Google Patents.
US3790224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Modulator for adaptive braking system
Assignee: Bendix Corp
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Filing: 1972-09-14
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Granted: 1974-02-05
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Expires: 1992-09-14
Abstract
Abstract A modulator for an adaptive braking system is disclosed which relieves braking pressure in the brakes of the wheels controlled by the system when an incipient skidding condition is sensed. The modulator includes the usual differential pressure responsive piston slidably mounted within a housing and movable to a position terminating fluid communication to the controlled brakes and thereafter relieving braking pressure when the modulator is actuated. The modulator is controlled by an electrically operated valve which is responsive to the output of the logic controller used in the adaptive braking system. The electrically operated valve normally communicates a pressure differential across the differential pressure responsive piston which assists the spring which maintains the differential pressure responsive piston in a position permitting fluid communication to the vehicle brakes. However, when an incipient skidding condition is sensed and the electrically operated valve means is actuated, the latter reverses the pressure differential across the differential pressure responsive piston to urge the latter in opposition to the resilient means to first terminate the braking pressure communication to the controlled brakes and to thereafter relieve braking pressure.
Inventors
- 👤 I Ritsema
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:25
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/26; B60T8/32; B60T8/34; B60T8/42; B60T8/4208; B60T8/4225; B60T8/4241; B60T8/425; B60T8/4258
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
422 words
A modulator for an adaptive braking system: a housing defining a chamber therewithin having an inlet, an outlet, and valve means for regulating fluid communication between said inlet and outlet; pressure differential responsive means for controlling said valve means, said pressure differential responsive means being shiftable from a normal position holding said valve means open to a position closing said valve means, said pressure differential responsive means thereafter moving to expand the volume of said chamber to thereby reduce the fluid pressure level at said outlet; resilient means yieldably urging said pressure differential responsive means to said normal position; and electrically operated valve means actuatable from a normal condition communicating higher fluid pressure on one side of said pressure differential responsive means and a lower fluid pressure on the other side of the latter whereby the pressure differential across said pressure differential responsive means assists said resilient means to urge the pressure differential responsive means to said normal position, said electrically actuated valve means being actuatable to an applied condition communicating a higher fluid pressure on said other side of said pressure differential responsive means and a lower pressure on said one side of the latter, whereby the pressure differential across said pressure differential responsive means urges the latter away from said normal position in opposition to said resilient means; said electrically operated valve means including first passage means communicated with said one side of said pressure differential responsive means, second passage means communicated to said other side of the latter, third passage means communicated with said higher fluid pressure, and fourth passage means communicated with said lower fluid pressure; said electrically operated valve means in said normal condition communicating said first passage means with said third passage means and said second passage means with said fourth passage means, said electrically operated valve means being actuatable to said applied condition to communicate said first passage means with said fourth passage means and said second passage means with said third passage means; at least a portion of said first and third passage means being disposed adjacent one another, said first and third passage means having a common wall separating said first and third passages; and a flow restricting orifice extending through said common wall to communicate said first and third passage means to limit the rate that the higher fluid pressure is communicated to said one side of the pressure responsive means after return of the electrically operated valve means to its normal condition after movement Of the latter to its applied condition.
Claim 2
Dependent Claim
422 words
A modulator for an adaptive braking system: a housing defining a chamber therewithin having an inlet, an outlet, and valve means for regulating fluid communication between said inlet and outlet; pressure differential responsive means for controlling said valve means, said pressure differential responsive means being shiftable from a normal position holding said valve means open to a position closing said valve means, said pressure differential responsive means thereafter moving to expand the volume of said chamber to thereby reduce the fluid pressure level at said outlet; resilient means yieldably urging said pressure differential responsive means to said normal position; and electrically operated valve means actuatable from a normal condition communicating higher fluid pressure on one side of said pressure differential responsive means and a lower fluid pressure on the other side of the latter whereby the pressure differential across said pressure differential responsive means assists said resilient means to urge the pressure differential responsive means to said normal position, said electrically actuated valve means being actuatable to an applied condition communicating a higher fluid pressure on said other side of said pressure differential responsive means and a lower pressure on said one side of the latter, whereby the pressure differential across said pressure differential responsive means urges the latter away from said normal position in opposition to said resilient means; said electrically operated valve means including first passage means communicated with said one side of said pressure differential responsive means, second passage means communicated to said other side of the latter, third passage means communicated with said higher fluid pressure, and fourth passage means communicated with said lower fluid pressure; said electrically operated valve means in said normal condition communicating said first passage means with said third passage means and said second passage means with said fourth passage means, said electrically operated valve means being actuatable to said applied condition to communicate said first passage means with said fourth passage means and said second passage means with said third passage means; at least a portion of said first and third passage means being disposed adjacent one another, said first and third passage means having a common wall separating said first and third passages; and a flow restricting orifice extending through said common wall to communicate said first and third passage means to limit the rate that the higher fluid pressure is communicated to said one side of the pressure responsive means after return of the electrically operated valve means to its normal condition after movement Of the latter to its applied condition.
Claim 3
Dependent Claim
81 words
The invention of claim 1: at least a portion of said second and fourth passage means being disposed adjacent one another, said second and fourth passages having a common wall separating said second and fourth passage means, and a flow restricting orifice extending through said common wall between the second and fourth passage means to control the rate of fluid communication from said other side of the pressure differential responsive means when the valve means is returned to the normal condition.
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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |