Patent US3590322A successfully refreshed from Google Patents.
US3590322A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Medical instrumentation system
Assignee: Sanmina Corp
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Filing: 1970-02-12
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Granted: 1971-06-29
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Expires: 1990-02-12
Abstract
Abstract A device for protecting patients against excessive currents which might flow through the patients from medical electrical equipment. A full-wave diode bridge rectifier circuit is connected between the patient and ground and provides a lowimpedance path between the patient and ground. A constant current source is connected to the bridge circuit to forward-bias the diodes. The current allowed to flow between the patient and ground is limited to the current supplied by the current source.
Inventors
- 👤 Travis C Carr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:37
CPC Classifications
H; H02; H02H; H02H9/00; H02H9/08; Y; Y10; Y10S; Y10S128/00; Y10S128/908
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
58 words
A patient protection device for use in medical electrical instrumentation, said device comprising unidirectional conduction means, a constant current supply connected to supply forward bias current to said unidirectional conduction means, and means for connecting said unidirectional conduction means between a patient and ground to limit the amount of current which can flow between the patient and ground.
Claim 2
Dependent Claim
58 words
A patient protection device for use in medical electrical instrumentation, said device comprising unidirectional conduction means, a constant current supply connected to supply forward bias current to said unidirectional conduction means, and means for connecting said unidirectional conduction means between a patient and ground to limit the amount of current which can flow between the patient and ground.
Claim 3
Dependent Claim
31 words
A device as in claim 1 including at least one physiological electrical instrument with a ground terminal connected to said ground and at least one signal terminal connected to said pAtient.
Claim 4
Dependent Claim
70 words
A patient protection device for use in medical electrical instrumentation, said device comprising a full-wave diode bridge rectifier circuit, a constant current supply connected to two opposite corners of said bridge circuit so as to provide forward bias current to each of the diodes in said bridge circuit, and means for connecting one of the other corners of said bridge circuit to ground and the remaining corner to a patient.
Claim 5
Dependent Claim
70 words
A patient protection device for use in medical electrical instrumentation, said device comprising a full-wave diode bridge rectifier circuit, a constant current supply connected to two opposite corners of said bridge circuit so as to provide forward bias current to each of the diodes in said bridge circuit, and means for connecting one of the other corners of said bridge circuit to ground and the remaining corner to a patient.
Claim 6
Dependent Claim
52 words
A device as in claim 3 in which said current supply includes two separate current sources, one connected to one of said opposite corners, and the other connected to the other of said opposite corners, said sources being connected together in series, and the common connection between them being connected to ground.
Claim 7
Dependent Claim
45 words
A device as in claim 3 in which the positive terminal of said constant current supply is connected to the anodes of two of said diodes, and the negative terminal of said constant current supply is connected to the cathodes of the other two diodes,
Claim 8
Dependent Claim
31 words
A device as in claim 3 including at least one physiological electrical instrument with a ground terminal connected to said ground and at least one signal terminal connected to said patient.
Claim 9
Dependent Claim
91 words
A medical instrumentation system, said system comprising a plurality of electrical physiological devices, each of said devices having an instrument ground lead, means for connecting each of said ground leads together to from a common instrument ground point, unidirectional conduction means, a constant current supply connected to supply forward bias current to said unidirectional conduction means, and means for connecting said unidirectional conduction means between said common instrument ground point and at least one patient to limit the amount of current which can flow between the patient and said ground point.
Claim 10
Dependent Claim
91 words
A medical instrumentation system, said system comprising a plurality of electrical physiological devices, each of said devices having an instrument ground lead, means for connecting each of said ground leads together to from a common instrument ground point, unidirectional conduction means, a constant current supply connected to supply forward bias current to said unidirectional conduction means, and means for connecting said unidirectional conduction means between said common instrument ground point and at least one patient to limit the amount of current which can flow between the patient and said ground point.
Claim 11
Dependent Claim
75 words
A system as in claim 7 in which said unidirectional conduction means comprises a full-wave diode bridge rectifier circuit, and a constant current supply connected to two opposite corners of said bridge circuit so as to provide forward bias current to each of the diodes in said bridge circuit, and said connecting means includes means for connecting one of the other corners of said bridge circuit to ground and the remaining corner to a patient.
Claim 12
Dependent Claim
29 words
A system as in claim 7 in which said connecting means includes means for connecting said unidirectional conduction means between said common ground point and a plurality of patients.
Claim 13
Dependent Claim
52 words
A system as in claim 8 in which said current supply includes two separate current sources, one connected to one of said opposite corners, and the other connected to the other of said opposite corners, said sources being connected together in series, and the common connection between them being connected to ground.
Claim 14
Dependent Claim
65 words
A patient ground circuit protection device for use in medical instrumentation, said device comprising variable impedance means for presenting a relatively low impedance between two terminals to currents below a predetermined maximum level, and for changing said impedance to a relatively very high value to currents above said level, and means for connecting said terminals of said variable impedance means between a patient and ground.
Claim 15
Dependent Claim
65 words
A patient ground circuit protection device for use in medical instrumentation, said device comprising variable impedance means for presenting a relatively low impedance between two terminals to currents below a predetermined maximum level, and for changing said impedance to a relatively very high value to currents above said level, and means for connecting said terminals of said variable impedance means between a patient and ground.
References Cited (Backward Citations)
US3515941A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |