US3816702A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic isothermal device
Assignee: Individual
•
Filing: 1972-06-26
•
Granted: 1974-06-11
•
Expires: 1992-06-26
Abstract
Abstract An electronic isothermal device capable of maintaining relatively even temperatures within a given container comprising an electronic circuit and a series of unique heaters in series therewith. The container is formed as a box having interior side walls made from boards such as printed circuits having a layer of conductive strands such as solder thereon positioned in a substantially uniform pattern. The boards forming side walls of the container are utilized as heating elements and are controlled by an electronic circuit comprising a series of discrete components or an integrated circuit in series therewith. The control circuit which can be placed on the circuit boards comprises an amplifier with a pair of transistors respectively connected to a thermistor and a resistor which serve to control a silicone controlled rectifier (SCR). The SCR controls a flow of current through the circuit boards for heating purposes when the thermistor registers changes in ambient temperature.
Inventors
- 👤 R Green
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:37
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/0014; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/20; G05D23/24; H03; H03L; H03L1/00; H03L1/02; H03L1/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
118 words
A container for creating a generally isothermal condition therein comprising: a plurality of plastic non-conductive boards formed into walls of a container having side, top, bottom, and back walls and an excess closure; a plurality of electrical conductors deposited and adhered on a majority of said non-conductive boards in the manner of printed circuit boards and thermally exposed to provide heating of the general interior area where an isothermal condition is to be maintained; an electrical resistance means enclosed within the walls of said container responsive to temperature changes in said container for controlling the current flowing through said conductors; and, changing means for causing changes in electrical current flow upon changes of resistance in said resistance means.
Claim 2
Dependent Claim
118 words
A container for creating a generally isothermal condition therein comprising: a plurality of plastic non-conductive boards formed into walls of a container having side, top, bottom, and back walls and an excess closure; a plurality of electrical conductors deposited and adhered on a majority of said non-conductive boards in the manner of printed circuit boards and thermally exposed to provide heating of the general interior area where an isothermal condition is to be maintained; an electrical resistance means enclosed within the walls of said container responsive to temperature changes in said container for controlling the current flowing through said conductors; and, changing means for causing changes in electrical current flow upon changes of resistance in said resistance means.
Claim 3
Dependent Claim
19 words
The container as claimed in claim 1 wherein said conductors comprise: solder which has been disposed on said boards.
Claim 4
Dependent Claim
29 words
The container as claimed in claim 1 further comprising: conductive material which has been disposed on said boards in a continuous manner by a metallic thin film deposition process.
Claim 5
Dependent Claim
14 words
The container as claimed in claim 1 wherein said resistance means comprise: a thermistor.
Claim 6
Dependent Claim
76 words
The container as claimed in claim 4 further comprising: a first and second transistor wherein said first transistor has its base connected to said thermistor; a resistance connected to the base of said second transistor; a silicone controlled rectifier having its gate connected to said second transistor for purposes of causing current to flow through said silicone controlled rectifier when said second transistor turns on; and, means to connect said silicone controlled rectifier to said conductors.
Claim 7
Dependent Claim
33 words
The container as claimed in claim 5 further comprising: a third transistor connected to said second transistor and said silicone controlled rectifier and biased to limit the voltage to said silicone controlled rectifier.
Claim 8
Dependent Claim
35 words
The container as claimed in claim 6 further comprising: means to connect said unit to an alternating current; and, a diode to cause said unit to operate on a particular cycle of said alternating current.
Claim 9
Dependent Claim
22 words
The container as claimed in claim 7 further comprising: variable resistance adjustment means for changing the effective operational characteristics of said thermistor.
Claim 10
Dependent Claim
20 words
The container as claimed in claim 1 wherein: said conductors are in series with each other and said resistance means.
Claim 11
Dependent Claim
38 words
The container as claimed in claim 1 wherein said resistance means comprises: a second series of conductors on said boards responsive to temperature changes within said container for controlling the flow of current through said first conductive strands.
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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) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |