US3759357A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brake saver circuit
Assignee: Caterpillar Inc
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Filing: 1972-03-23
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Granted: 1973-09-18
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Expires: 1992-03-23
Abstract
Abstract There is disclosed a brake control system in conjunction with drive control system of a vehicle wherein said systems are interconnected for simultaneous release of spring applied brakes upon activation of the drive control circuit, providing control pressure is adequate for full release of the brakes.
Inventors
- 👤 D Bianchetta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:22
CPC Classifications
B; B60; B60T; B60T13/00; B60T13/10; B60T13/12; B60T13/22; B60K; B60K17/00; B60K17/04; B60K17/10; B60T11/00; B60T11/10; B60T11/103
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
132 words
A brake system for a vehicle, said brake system comprising: actuating means including spring means operatively connected to automatically engage said brake system; control means including a source of pressurized fluid operative to initiate forward and reverse drive of said vehicle and including piston means responsive to said pressurized fluid to overcome said actuating means to disengage said brake system; said control means further including pressure responsive valve means, operative in response to a failure of said control pressure to maintain a pre-determined minimum pressure, to bypass said means to disengage said brake system; and, said valve means comprises a first valve responsive to said source of pressurized fluid to communicate fluid from said control means to shift a second valve operative to direct fluid from said source to operate said piston.
Claim 2
Dependent Claim
132 words
A brake system for a vehicle, said brake system comprising: actuating means including spring means operatively connected to automatically engage said brake system; control means including a source of pressurized fluid operative to initiate forward and reverse drive of said vehicle and including piston means responsive to said pressurized fluid to overcome said actuating means to disengage said brake system; said control means further including pressure responsive valve means, operative in response to a failure of said control pressure to maintain a pre-determined minimum pressure, to bypass said means to disengage said brake system; and, said valve means comprises a first valve responsive to said source of pressurized fluid to communicate fluid from said control means to shift a second valve operative to direct fluid from said source to operate said piston.
Claim 3
Dependent Claim
154 words
In a vehicle having brakes and hydraulic control means including a source of pressurized fluid operative to initiate forward and reverse drive of said vehicle, a brake control system comprising: means for normally biasing said brakes into an engaged position; brake releasing means including fluid actuated piston means operative in response to said hydraulic control means for automatically releasing said brakes upon initiation of forward or reverse drive of said vehicle; means including pressure responsive valve means responsive upon the failure of said pressurized fluid to maintain a pre-determined minimum pressure, to by-pass said means for releasing said brakes; said pressure responsive valve means comprises a first valve responsive to said source of pressurized fluid to communicate fluid directed by said hydraulic control means to operate a second valve; and, said second valve being responsive to said fluid from said control means to direct fluid from said source to said fluid actuated piston means.
Claim 4
Dependent Claim
154 words
In a vehicle having brakes and hydraulic control means including a source of pressurized fluid operative to initiate forward and reverse drive of said vehicle, a brake control system comprising: means for normally biasing said brakes into an engaged position; brake releasing means including fluid actuated piston means operative in response to said hydraulic control means for automatically releasing said brakes upon initiation of forward or reverse drive of said vehicle; means including pressure responsive valve means responsive upon the failure of said pressurized fluid to maintain a pre-determined minimum pressure, to by-pass said means for releasing said brakes; said pressure responsive valve means comprises a first valve responsive to said source of pressurized fluid to communicate fluid directed by said hydraulic control means to operate a second valve; and, said second valve being responsive to said fluid from said control means to direct fluid from said source to said fluid actuated piston means.
Claim 5
Dependent Claim
153 words
In a vehicle having hydraulic drive means comprising a pump for supplying pressurized fluid to power a hydraulic motor operatively connected to propell said vehicle, brake means and hydraulic control means operative to initiate forward and reverse drive of said vehicle, a brake control system comprising: means for normally biasing said brakes into an engaged position; brake releasing means operative in response to said hydraulic control means for automatically releasing said brakes upon initiation of forward or reverse drive of said vehicle; said control means including valve means operative to control the supply of hydraulic fluid to said motor, and pilot control means to operate said valve means; means responsive upon the failure of said pressurized fluid to maintain a pre-determined minimum pressure to by-pass said means for releasing said brakes; and, said by-pass means comprising first valve means responsive to said source and second valve means responsive to said pilot control means.
Claim 6
Dependent Claim
153 words
In a vehicle having hydraulic drive means comprising a pump for supplying pressurized fluid to power a hydraulic motor operatively connected to propell said vehicle, brake means and hydraulic control means operative to initiate forward and reverse drive of said vehicle, a brake control system comprising: means for normally biasing said brakes into an engaged position; brake releasing means operative in response to said hydraulic control means for automatically releasing said brakes upon initiation of forward or reverse drive of said vehicle; said control means including valve means operative to control the supply of hydraulic fluid to said motor, and pilot control means to operate said valve means; means responsive upon the failure of said pressurized fluid to maintain a pre-determined minimum pressure to by-pass said means for releasing said brakes; and, said by-pass means comprising first valve means responsive to said source and second valve means responsive to said pilot control means.
Claim 7
Dependent Claim
55 words
The invention of claim 3 wherein first valve means is operative to communicate fluid from said pilot control means for operation of said second valve means; and, said second valve means is operative in response to the fluid from said pilot control means to direct fluid from said source to operate said brake releasing means.
References Cited (Backward Citations)
US2171204A
Cited
US3439579A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |