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US3573759A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic field coupled superconducting quantum interference system

Assignee: Ford Motor Co
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Filing: 1969-01-24
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Granted: 1971-04-06
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Expires: 1989-01-24
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Abstract

Abstract This disclosure relates to an electrical circuit component including a superconductive quantum interference device having a loop of superconducting material with a weak link positioned therein. The loop of superconducting material and the weak link enclose an area for the reception of magnetic flux. Means are positioned adjacent the superconductive quantum interference device for producing a varying magnetic field at the device to induce a current therein. The magnitude of the varying magnetic field is sufficient to induce a critical current in the weak link. As a result, the current induced in the superconductive quantum interference device alternately increases and decreases as the number of flux quanta changes in the area enclosed by the superconducting material and weak link. The disclosure also relates to a process of inducing a nonlinear electric current in a superconductive quantum interference device having a loop of superconducting material with a weak link positioned therein. It comprises placing this device in a superconducting state and locating an inductive member magnetically adjacent thereto. A varying current is applied to the inductive device to induce a current in the superconductive quantum interference device. The magnitude of this varying current is sufficient to induce a critical current in the weak link, and, as a result, the current alternately increases to the value of the critical current through the weak link and decreases to some lower value as the number of flux quanta changes in the area enclosed by the superconducting material and weak link.

Inventors

  • 👤 James E Zimmerman
  • 👤 Arnold H Silver

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 22:48
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/44; H; H03; H03F; H03F19/00; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/873; Y10S505/874

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 139 words
The process of inducing a nonlinear electrical current in a superconductive quantum interference device having a loop of superconducting material with a weak link positioned therein comprising placing the superconductive quantum interference device in the superconductive state in a cryogenic medium, locating an inductive member magnetically adjacent the superconductive quantum interference device and applying a varying current to the inductive device to induce a current in the superconductive quantum interference device, the magnitude of the varying current applied to the inductive member being sufficient to induce a critical current in said weak link whereby the current in the superconductive quantum interference device alternately increases to the value of the critical current through the weak link and decreases to some lower value as the number of flux quanta changes in the area enclosed by the superconducting material and weak link.
Claim 2
Dependent Claim 139 words
The process of inducing a nonlinear electrical current in a superconductive quantum interference device having a loop of superconducting material with a weak link positioned therein comprising placing the superconductive quantum interference device in the superconductive state in a cryogenic medium, locating an inductive member magnetically adjacent the superconductive quantum interference device and applying a varying current to the inductive device to induce a current in the superconductive quantum interference device, the magnitude of the varying current applied to the inductive member being sufficient to induce a critical current in said weak link whereby the current in the superconductive quantum interference device alternately increases to the value of the critical current through the weak link and decreases to some lower value as the number of flux quanta changes in the area enclosed by the superconducting material and weak link.
Claim 3
Dependent Claim 44 words
The process recited in claim 1 in which a further inductive member is placed magnetically adjaceNt the superconductive quantum interference device whereby voltages are generated in such further inductive member in response to the changes in the number of flux quanta in said area.
Claim 4
Dependent Claim 62 words
The process recited in claim 1 in which a further inductive member is placed magnetically adjacent the superconductive quantum interference device and at least partially magnetically shielded from the first mentioned inductive member by the superconductive quantum interference device whereby voltages are generated in said further inductive member in response to the changes in the number of flux quanta in said area.
Claim 5
Dependent Claim 29 words
The process recited in claim 1 in which the magnetic effects of the presence of the superconductive quantum interference device are detected directly in the magnetically adjacent inductive member.
Claim 6
Dependent Claim 20 words
The process recited in claim 1 in which only the superconductive quantum interference device is placed in the cryogenic medium.
Claim 7
Dependent Claim 44 words
The process recited in claim 1 in which the varying current applied to the inductive device is an alternating current having an amplitude during a substantial time period during both negative and positive excursions sufficient to induce a critical current in the weak link.

References Cited (Backward Citations)

US3049686A Cited
US3419712A Cited
US3335363A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-04-05 1974-10-05 1975-04-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-04-05 1978-10-05 1979-04-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-04-05 1982-10-05 1983-04-06 $7700.00 Window Closed / Lapsed

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