Patent US3886932A successfully refreshed from Google Patents.
US3886932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overcurrent protective circuit
Assignee: Picker International GmbH
•
Filing: 1974-02-14
•
Granted: 1975-06-03
•
Expires: 1994-02-14
Abstract
Abstract An overcurrent protective circuit. There is disclosed a circuit for automatically interrupting the flow of current in a critical conductor when that current exceeds a predetermined value. The disclosed circuit can interrupt the current flow for a predetermined time. The circuit has particular utility in conjunction with electro-medical patient monitoring equipment, where currents must be maintained below levels dangerous to the patient.
Inventors
- 👤 Klaus Suessmilch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:24
CPC Classifications
H; H02; H02H; H02H1/00; H02H1/0007; H02H3/00; H02H3/02; H02H3/04; H02H3/08; Y; Y10; Y10S; Y10S128/00; Y10S128/908
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
104 words
An overcurrent patient-protective device for use with patient vital sign monitoring equipment, said device comprising means for sensing current flow between said equipment and said patient, means for converting said current flow to a DC voltage, means for generating a reference voltage, means for comparing said DC voltage with said reference voltage, means for generating a signal when said DC voltage exceeds said reference voltage, said signal generating means including means for maintaining said signal for a predetermined period of time, and electromechanical switch means responsive to operation of said signal generating means for interrupting said current flow for the duration of said signal.
Claim 2
Dependent Claim
104 words
An overcurrent patient-protective device for use with patient vital sign monitoring equipment, said device comprising means for sensing current flow between said equipment and said patient, means for converting said current flow to a DC voltage, means for generating a reference voltage, means for comparing said DC voltage with said reference voltage, means for generating a signal when said DC voltage exceeds said reference voltage, said signal generating means including means for maintaining said signal for a predetermined period of time, and electromechanical switch means responsive to operation of said signal generating means for interrupting said current flow for the duration of said signal.
Claim 3
Dependent Claim
25 words
A device as recited in claim 1 further comprising audio-visual alarm means and wherein said switch means further includes means for activating said alarm means.
Claim 4
Dependent Claim
16 words
A device as recited in claim 1 and wherein said sensing means comprises precision resistance means.
Claim 5
Dependent Claim
29 words
A device as recited in claim 3 and wherein said reference voltage generating means includes other means for activating said switch means when said current flow exceeds 4 microamperes.
Claim 6
Dependent Claim
16 words
A device as recited in claim 1 and wherein said converting means comprises rectifier circuit means.
Claim 7
Dependent Claim
17 words
A device as recited in claim 1 and wherein said comparing means comprises differential amplifier circuit means.
Claim 8
Dependent Claim
16 words
A device as recited in claim 1 and wherein said switch means comprises current-activated relay means.
Claim 9
Dependent Claim
41 words
A device as recited in claim 1 wherein said sensing means includes other means for sensing current flows in a plurality of conductors, and means for adding the respective current flows to provide a total current flow for said converting means.
Claim 10
Dependent Claim
16 words
A device as recited in claim 8 and wherein said sensing means comprises precision resistance means.
Claim 11
Dependent Claim
17 words
A device as recited in claim 9 and wherein said comparing means comprises differential amplifier circuit means.
Claim 12
Dependent Claim
108 words
Electro-medical patient monitoring equipment comprising circuit means for monitoring certain vital signs of said patient, terminal means for conductively connecting said patient to said circuit means, and overcurrent patient-protective means comprising seriatim: means for sensing current flow in said terminal means, means for converting said current flow to a DC voltage, means for generating a reference voltage, means for comparing said DC voltage with said reference voltage, means for generating a signal when said DC voltage exceeds said reference voltage, means for maintaining said signal for a predetermined period of time, and electromechanical switch means responsive to operation of said signal generating means for interrupting said current flow.
Claim 13
Dependent Claim
108 words
Electro-medical patient monitoring equipment comprising circuit means for monitoring certain vital signs of said patient, terminal means for conductively connecting said patient to said circuit means, and overcurrent patient-protective means comprising seriatim: means for sensing current flow in said terminal means, means for converting said current flow to a DC voltage, means for generating a reference voltage, means for comparing said DC voltage with said reference voltage, means for generating a signal when said DC voltage exceeds said reference voltage, means for maintaining said signal for a predetermined period of time, and electromechanical switch means responsive to operation of said signal generating means for interrupting said current flow.
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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |