US3249930A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Parametric visual system indicator
Assignee: Northrop Grumman Space and Mission Systems Corp
•
Filing: 1960-02-04
•
Granted: 1966-05-03
•
Expires: 1980-02-04
Abstract
No abstract record available.
Inventors
- 👤 Maurice W Windsor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:50
CPC Classifications
G; G08; G08B; G08B5/00; G08B5/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
110 words
A VISUAL INDICATOR FOR INDICATING THE CONDITION OF A SYSTEM SUBJECT TO VARIATION BETWEEN TWO GIVEN STATES, SAID INDICATOR COMPRISING: A THERMOCHROMIC MEMBER HAVING A GIVEN CRITICAL TEMPERATURE AT WHICH IT REVERSIBLY CHANGES FROM ONE COLOR BELOW SAID CRITICAL TEMPERATURE TO ANOTHER COLOR ABOVE SAID CRITICAL TEMPERATURE; AN ELECTRIC HEATER THERMALLY COUPLED TO SAID MEMBER; CIRCUIT MEANS FOR SUPPLYING AN ELECTRIC CURRENT OF FIXED MAGNITUDE THAT IS SUFFICIENT TO HEAT SAID THERMOCHROMIC MEMBER ABOVE SAID CRITICAL TEMPERATURE; A HEAT MODIFYING ELEMENT POSITIONED IN HEAT INTERCEPTING RELATION BETWEEN SAID HEATER AND SAID MEMBER; AND MEANS FOR AUTOMATICALLY ALTERING A CONDITION OF SAID ELEMENT, AS A FUNCTION OF THE VARIATIONS IN THE
Claim 2
Dependent Claim
110 words
A VISUAL INDICATOR FOR INDICATING THE CONDITION OF A SYSTEM SUBJECT TO VARIATION BETWEEN TWO GIVEN STATES, SAID INDICATOR COMPRISING: A THERMOCHROMIC MEMBER HAVING A GIVEN CRITICAL TEMPERATURE AT WHICH IT REVERSIBLY CHANGES FROM ONE COLOR BELOW SAID CRITICAL TEMPERATURE TO ANOTHER COLOR ABOVE SAID CRITICAL TEMPERATURE; AN ELECTRIC HEATER THERMALLY COUPLED TO SAID MEMBER; CIRCUIT MEANS FOR SUPPLYING AN ELECTRIC CURRENT OF FIXED MAGNITUDE THAT IS SUFFICIENT TO HEAT SAID THERMOCHROMIC MEMBER ABOVE SAID CRITICAL TEMPERATURE; A HEAT MODIFYING ELEMENT POSITIONED IN HEAT INTERCEPTING RELATION BETWEEN SAID HEATER AND SAID MEMBER; AND MEANS FOR AUTOMATICALLY ALTERING A CONDITION OF SAID ELEMENT, AS A FUNCTION OF THE VARIATIONS IN THE
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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) | 1969-05-02 | 1969-11-01 | 1970-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-02 | 1973-11-01 | 1974-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-02 | 1977-11-01 | 1978-05-03 | $7700.00 | Window Closed / Lapsed |