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US3305698A Expired / Lapsed US ⏱️ 0.0 years remaining

Electric motor overheating protection circuit

Assignee: Motorola Solutions Inc
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Filing: 1963-09-16
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Granted: 1967-02-21
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Expires: 1983-09-16
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Abstract

No abstract record available.

Inventors

  • 👤 David W Bargen
  • 👤 Bradford O Van Ness

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 11:13
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/1909; G05D23/1927; G05D23/20; G05D23/24; H; H02; H02H; H02H7/00; H02H7/08; H02H7/085; H02H7/0852; H02K; H02K11/00; H02K11/20; H02K11/25

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 256 words
AN ELECTRIC CONTROL CIRCUIT INCLUDING IN COMBINATION: INPUT TERMINAL MEANS FOR CONNECTING THE CONTROL CIRCUIT TO A SOURCE OF ALTERNATING CURRENT VOLTAGE; OUTPUT TERMINAL MEANS; CIRCUIT MEANS INCLUDING A SWITCHING DEVICE COUPLED TO SAID INPUT TERMINAL MEANS AND TO SAID OUTPUT TERMINAL MEANS; SAID SWITCHING DEVICE HAVING A FIRST CONDUCTIVE STATE WHEREBY SAID ALTERNATING CURRENT VOLTAGE IS APPLIED TO SAID OUTPUT TERMINAL MEANS AND A SECOND NON-CONDUCTIVE STATE; A FIRST TRANSFORMER HAVING A PRIMARY WINDING CONNECTED TO SAID INPUT TERMINAL MEANS AND HAVING A FIRST SECONDARY WINDING AND A SECOND SECONDARY WINDING; A SECOND TRANSFORMER HAVING FIRST PRIMARY WINDING CONNECTED TO SAID OUTPUT TERMINAL MEANS AND HAVING A SECOND PRIMARY WINDING AND A SECONDARY WINDING; A VARIABLE RESISTANCE SENSING ELEMENT; A PAIR OF CONTROL TERMINALS COUPLED TO SAID VARIABLE RESISTANCE SENSING ELEMENT; CIRCUIT MEANS INCLUDING SAID CONTROL TERMINALS FOR CONNECTING SAID FIRST SECONDARY WINDING OF SAID FIRST TRANSFORMER, SAID SECOND PRIMARY WINDING OF SAID SECOND TRANSFORMER AND SAID VARIABLE RESISTANCE SENSING ELEMENT IN SERIES; FIRST RECTIFYING CIRCUIT MEANS CONNECTED TO SAID SECOND SECONDARY WINDING OF SAID FIRST TRANSFORMER AND TO SAID SWITCHING DEVICE FOR PRODUCING A FIRST CONTROL SIGNAL OF A POLARITY TO RENDER SAID SWITCHING DEVICE NONCONDUCTIVE; AND SECOND RECTIFYING CIRCUIT MEANS CONNECTED TO SAID SECONDARY WINDING OF SAID SECOND TRANSFORMER AND TO SAID FIRST RECTIFYING CIRCUIT MEANS; SAID SECOND RECTIFYING MEANS PRODUCING A SECOND CONTROL SIGNAL OF A POLARITY TO COUNTERBALANCE SAID FIRST CONTROL SIGNAL AND RENDER SAID SWITCHING DEVICE CONDUCTIVE ONLY WHEN THE RESISTANCE OF THE SENSING ELEMENT VARIES BEYOND A PREDETERMINED VALUE.
Claim 2
Dependent Claim 256 words
AN ELECTRIC CONTROL CIRCUIT INCLUDING IN COMBINATION: INPUT TERMINAL MEANS FOR CONNECTING THE CONTROL CIRCUIT TO A SOURCE OF ALTERNATING CURRENT VOLTAGE; OUTPUT TERMINAL MEANS; CIRCUIT MEANS INCLUDING A SWITCHING DEVICE COUPLED TO SAID INPUT TERMINAL MEANS AND TO SAID OUTPUT TERMINAL MEANS; SAID SWITCHING DEVICE HAVING A FIRST CONDUCTIVE STATE WHEREBY SAID ALTERNATING CURRENT VOLTAGE IS APPLIED TO SAID OUTPUT TERMINAL MEANS AND A SECOND NON-CONDUCTIVE STATE; A FIRST TRANSFORMER HAVING A PRIMARY WINDING CONNECTED TO SAID INPUT TERMINAL MEANS AND HAVING A FIRST SECONDARY WINDING AND A SECOND SECONDARY WINDING; A SECOND TRANSFORMER HAVING FIRST PRIMARY WINDING CONNECTED TO SAID OUTPUT TERMINAL MEANS AND HAVING A SECOND PRIMARY WINDING AND A SECONDARY WINDING; A VARIABLE RESISTANCE SENSING ELEMENT; A PAIR OF CONTROL TERMINALS COUPLED TO SAID VARIABLE RESISTANCE SENSING ELEMENT; CIRCUIT MEANS INCLUDING SAID CONTROL TERMINALS FOR CONNECTING SAID FIRST SECONDARY WINDING OF SAID FIRST TRANSFORMER, SAID SECOND PRIMARY WINDING OF SAID SECOND TRANSFORMER AND SAID VARIABLE RESISTANCE SENSING ELEMENT IN SERIES; FIRST RECTIFYING CIRCUIT MEANS CONNECTED TO SAID SECOND SECONDARY WINDING OF SAID FIRST TRANSFORMER AND TO SAID SWITCHING DEVICE FOR PRODUCING A FIRST CONTROL SIGNAL OF A POLARITY TO RENDER SAID SWITCHING DEVICE NONCONDUCTIVE; AND SECOND RECTIFYING CIRCUIT MEANS CONNECTED TO SAID SECONDARY WINDING OF SAID SECOND TRANSFORMER AND TO SAID FIRST RECTIFYING CIRCUIT MEANS; SAID SECOND RECTIFYING MEANS PRODUCING A SECOND CONTROL SIGNAL OF A POLARITY TO COUNTERBALANCE SAID FIRST CONTROL SIGNAL AND RENDER SAID SWITCHING DEVICE CONDUCTIVE ONLY WHEN THE RESISTANCE OF THE SENSING ELEMENT VARIES BEYOND A PREDETERMINED VALUE.

References Cited (Backward Citations)

US3032690A Cited
US3071718A Cited
US3225280A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1970-02-20 1970-08-22 1971-02-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1974-02-20 1974-08-22 1975-02-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1978-02-20 1978-08-22 1979-02-21 $7700.00 Window Closed / Lapsed

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