Patent US7591848B2 successfully refreshed from Google Patents.
Patent US3240534A successfully refreshed from Google Patents.
US3240534A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tractor trailer brake system
Assignee: ZF Active Safety US Inc
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Filing: 1963-01-09
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Granted: 1966-03-15
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Expires: 1983-01-09
Abstract
No abstract record available.
Inventors
- 👤 Stelzer William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:34
CPC Classifications
B; B60; B60T; B60T15/00; B60T15/02; B60T15/04; B60T15/14; B60T13/00; B60T13/10; B60T13/58; B60T15/18; B60T15/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
211 words
A TRACTOR TRAILER BRAKE SYSTEM COMPRISING BRAKE ACTUATORS ON THE TRACTOR, BRAKE ACTUATORS ON THE TRAILER, A MANUALLY OPERABLE VALVE ON THE TRACTOR FOR CONNECTING SAID TRACTOR BRAKE ACTUATORS TO A SOURCE OF PRESSURE, AND A RELAY VALVE MECHANISM ON THE TRAILER COMPRISING A HOUSING HAVING A FIRST CHAMBER CONNECTED TO SAID CONTROL VALVE, A SECOND CHAMBER DIRECTLY CONNECTED TO SAID TRAILER BRAKE ACTUATORS, A PRESSURE MOVABLE MEMBER DIVIDING SAID CHAMBERS, SPRING MEANS BIASING SAID PRESSURE MOVABLE MEMBER FOR MOVEMENT IN ONE DIRECTION, A CONTROL CHAMBER, MEANS FOR MAINTAINING PRESSURE IN SAID CONTROL CHAMBER TO NORMALLY OVERCOME SAID SPRING MEANS, MEANS OPERABLE UPON OPERATION OF SAID MANUALLY OPERABLE VALVE FOR RELIEVING PRESSURE IN SAID CONTROL CHAMBER TO RELEASE SAID SPRING MEANS, MEANS OPERABLE UPON SAID MOVEMENT OF SAID PRESSURE MOVABLE MEMBER BY SAID SPRING MEANS FOR ADMITTING PRESSURE FROM SAID SOURCE TO SAID SECOND CHAMBER AND THUS TO SAID TRAILER BRAKE ACTUATORS, INCREASING PRESSURE IN SAID SECOND CHAMBER ACTING AGAINST SAID SPRING MEANS TO OVERCOME THE LATTER WHEN PRESSURE IN SAID SECOND CHAMBER REACHES A PREDETERMINED POINT TO CUT OFF THE ADMISSION OF PRESSURE TO SAID SECOND CHAMBER, AND MEANS OPERATIVE UPON A DECREASE IN PRESSURE AVAILABLE IN SAID SOURCE FOR SUPPLYING ALL OF SUCH AVAILABLE PRESSURE TO SAID SECOND CHAMBER.
Claim 2
Dependent Claim
211 words
A TRACTOR TRAILER BRAKE SYSTEM COMPRISING BRAKE ACTUATORS ON THE TRACTOR, BRAKE ACTUATORS ON THE TRAILER, A MANUALLY OPERABLE VALVE ON THE TRACTOR FOR CONNECTING SAID TRACTOR BRAKE ACTUATORS TO A SOURCE OF PRESSURE, AND A RELAY VALVE MECHANISM ON THE TRAILER COMPRISING A HOUSING HAVING A FIRST CHAMBER CONNECTED TO SAID CONTROL VALVE, A SECOND CHAMBER DIRECTLY CONNECTED TO SAID TRAILER BRAKE ACTUATORS, A PRESSURE MOVABLE MEMBER DIVIDING SAID CHAMBERS, SPRING MEANS BIASING SAID PRESSURE MOVABLE MEMBER FOR MOVEMENT IN ONE DIRECTION, A CONTROL CHAMBER, MEANS FOR MAINTAINING PRESSURE IN SAID CONTROL CHAMBER TO NORMALLY OVERCOME SAID SPRING MEANS, MEANS OPERABLE UPON OPERATION OF SAID MANUALLY OPERABLE VALVE FOR RELIEVING PRESSURE IN SAID CONTROL CHAMBER TO RELEASE SAID SPRING MEANS, MEANS OPERABLE UPON SAID MOVEMENT OF SAID PRESSURE MOVABLE MEMBER BY SAID SPRING MEANS FOR ADMITTING PRESSURE FROM SAID SOURCE TO SAID SECOND CHAMBER AND THUS TO SAID TRAILER BRAKE ACTUATORS, INCREASING PRESSURE IN SAID SECOND CHAMBER ACTING AGAINST SAID SPRING MEANS TO OVERCOME THE LATTER WHEN PRESSURE IN SAID SECOND CHAMBER REACHES A PREDETERMINED POINT TO CUT OFF THE ADMISSION OF PRESSURE TO SAID SECOND CHAMBER, AND MEANS OPERATIVE UPON A DECREASE IN PRESSURE AVAILABLE IN SAID SOURCE FOR SUPPLYING ALL OF SUCH AVAILABLE PRESSURE TO SAID SECOND CHAMBER.
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) | 1969-03-14 | 1969-09-13 | 1970-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-03-14 | 1973-09-13 | 1974-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-03-14 | 1977-09-13 | 1978-03-15 | $7700.00 | Window Closed / Lapsed |