Patent US2784391A successfully refreshed from Google Patents.
Patent US3656025A successfully refreshed from Google Patents.
US3656025A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current limiter
Assignee: Individual
•
Filing: 1971-05-04
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Granted: 1972-04-11
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Expires: 1991-05-04
Abstract
Abstract This invention relates to current limiters particularly for medical equipment. The current limiter of this invention is adapted to be inserted directly into the line which connects a patient to an electronic device. It comprises a pair of field effect transistors connected in series with a biasing resistor. One of the transistors has a lower cut-off potential than the other, and the one with the higher cut-off point also has substantially higher resistance and breakdown strength.
Inventors
- 👤 Denes Roveti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:41
CPC Classifications
H; H03; H03G; H03G11/00; H03G11/002; Y; Y10; Y10S; Y10S128/00; Y10S128/908; Y10S323/00; Y10S323/911
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
127 words
A current limiter protective device for use with monitoring equipment, said device comprising a first electronic switch comprising a first main conduction path and a first control element, a second electronic switch having a second main conduction path and a second control element, said first control element responding to a relatively low switching potential to drive said first main conduction path into a saturation condition, said second control element responding to a relatively high switching potential to drive said second conduction path into saturation, a biasing impedance means for connecting said first and second main conduction paths and said impedance in series, means for connecting said first and second control elements to said impedance, and means for connecting said series arrangement into a circuit to be protected.
Claim 2
Dependent Claim
127 words
A current limiter protective device for use with monitoring equipment, said device comprising a first electronic switch comprising a first main conduction path and a first control element, a second electronic switch having a second main conduction path and a second control element, said first control element responding to a relatively low switching potential to drive said first main conduction path into a saturation condition, said second control element responding to a relatively high switching potential to drive said second conduction path into saturation, a biasing impedance means for connecting said first and second main conduction paths and said impedance in series, means for connecting said first and second control elements to said impedance, and means for connecting said series arrangement into a circuit to be protected.
Claim 3
Dependent Claim
31 words
The device defined in claim 1 wherein said first and second electronic switches comprise components which have low impedances in their normal operating ranges and higher impedances in their saturation ranges.
Claim 4
Dependent Claim
149 words
A current limiter protective device for use with monitoring equipment, said device comprising a first pair of electronic switches connected together in series, a second pair of electronic switches connected together in series, each of said switches of said first and second pairs including a control element, a switching impedance, means for connecting said swItching impedance in series with said first and second pairs, means for connecting the control elements of said first pair to said impedance to respond to excessive current flowing in a first direction through said impedance to drive the switches of said first pair into saturation, means for connecting the control elements of said second pair to said impedance to respond to excessive current flowing in a second direction through said impedance to drive the switches of said second pair into saturation, and means for connecting said series arrangement into a circuit to be monitored.
Claim 5
Dependent Claim
149 words
A current limiter protective device for use with monitoring equipment, said device comprising a first pair of electronic switches connected together in series, a second pair of electronic switches connected together in series, each of said switches of said first and second pairs including a control element, a switching impedance, means for connecting said swItching impedance in series with said first and second pairs, means for connecting the control elements of said first pair to said impedance to respond to excessive current flowing in a first direction through said impedance to drive the switches of said first pair into saturation, means for connecting the control elements of said second pair to said impedance to respond to excessive current flowing in a second direction through said impedance to drive the switches of said second pair into saturation, and means for connecting said series arrangement into a circuit to be monitored.
Claim 6
Dependent Claim
33 words
The device defined in claim 3 therein the switches of said first and second pair comprise components which have low impedances in their normal operating ranges and higher impedances in their saturation ranges.
Claim 7
Dependent Claim
29 words
The device defined in claim 4 further including a high voltage protective device connected across said series arrangement of said first and second pairs of switches and said impedance.
Claim 8
Dependent Claim
18 words
The device defined in claim 5 wherein said high voltage protective device is a hermetrically sealed arc gap.
Claim 9
Dependent Claim
29 words
The device defined in claim 3 further including a high voltage protective device connected across said series arrangement of said first and second pairs of switches and said impedance.
Claim 10
Dependent Claim
18 words
The device defined in claim 7 wherein said high voltage protective device is a hermetrically sealed arc gap.
Claim 11
Dependent Claim
37 words
The device defined in claim 3 wherein said means for connection into a circuit to be monitored includes a first terminal connector generally comprising a post connector and a second terminal connector generally comprising a spring connector.
Claim 12
Dependent Claim
64 words
The device defined in claim 9 wherein said spring connector comprises a first conductive element and a second conductive element, each of said conductive elements having a perforation, the perforations in said first and second elements not being aligned, and means for deflecting said second conductive element to align the perforations in said first and second conductive elements to accept a monitoring terminal therein.
References Cited (Backward Citations)
US3369129A
Cited
US3521087A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |