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US3906476A Expired / Lapsed US ⏱️ 0.0 years remaining

Warning system

Assignee: Denso Corp
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Filing: 1973-08-17
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Granted: 1975-09-16
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Expires: 1993-08-17
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Abstract

Abstract There is provided a warning system comprising a first coil, a second coil for producing a magnetic field whose direction is opposite to that of the magnetic field by the first coil, and a reed switch system having contacts which are opened and closed by the magnetomotive forces of the coils and which, once closed, are held in the closed position, whereby the contacts of the reed switch system are closed by the closing of a switch for detecting a fault in a system subject to fault detection to give a warning to the operator and moreover even when a power supply switch which has once been turned off is closed again, the contacts are held in the closed position so far as the fault has not been removed. Thus, the warning system of this invention is highly reliable.

Inventors

  • 👤 Hisashi Yonezu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 13:10
CPC Classifications
H; H01; H01H; H01H51/00; H01H51/28; B; B60; B60T; B60T17/00; B60T17/18; B60T17/22

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 144 words
A warning system comprising a self-holding type reed switch having contacts which close upon application of an external magnetic field and which are retained in said closed position even after the removal of said external magnetic field, a first coil for producing a magnetic field sufficient to close said reed switch, a second coil for producing a magnetic field whose direction is opposite to that of the magnetic field of said first coil wherein the strength of the resultant magnetic field of the magnetic fields of the first and second coils is not sufficient to close said reed switch when in the open position, but is sufficient to open said reed switch when in the closed position, a sensor switch means connected to a power supply through said first coil which senses a fault condition, and a warning means connected to said reed switch.
Claim 2
Dependent Claim 144 words
A warning system comprising a self-holding type reed switch having contacts which close upon application of an external magnetic field and which are retained in said closed position even after the removal of said external magnetic field, a first coil for producing a magnetic field sufficient to close said reed switch, a second coil for producing a magnetic field whose direction is opposite to that of the magnetic field of said first coil wherein the strength of the resultant magnetic field of the magnetic fields of the first and second coils is not sufficient to close said reed switch when in the open position, but is sufficient to open said reed switch when in the closed position, a sensor switch means connected to a power supply through said first coil which senses a fault condition, and a warning means connected to said reed switch.
Claim 3
Dependent Claim 30 words
A warning system according to claim 1, wherein said first and second coils are connected in series with each other, and wherein one end of said second coil is grounDed.
Claim 4
Dependent Claim 16 words
A warning system according to claim 1 further including a protective resistor for said reed switch.
Claim 5
Dependent Claim 33 words
A warning system according to claim 1, wherein said self-holding type reed switch comprises an ordinary reed switch, and a permanent magnet for holding said ordinary reed switch in the closed position thereof.
Claim 6
Dependent Claim 143 words
A warning system comprising a self-holding type reed switch having contacts which close upon application of an external magnetic field thereto and which are retained in said closed position even after the removal of said external magnetic field, a first coil for producing a magnetic field sufficient to close said reed switch, a second coil for producing a magnetic field whose direction is opposite to that of the magnetic field of said first coil and whose strength is substantially the same as that of the magnetic field of said first coil, said first and second coils being wound independently of each other on both sides of the central portion of said reed switch, a power supply, a sensor switch means connected to said power supply through said first coil which senses a fault condition, and a warning means connected to said reed switch.
Claim 7
Dependent Claim 143 words
A warning system comprising a self-holding type reed switch having contacts which close upon application of an external magnetic field thereto and which are retained in said closed position even after the removal of said external magnetic field, a first coil for producing a magnetic field sufficient to close said reed switch, a second coil for producing a magnetic field whose direction is opposite to that of the magnetic field of said first coil and whose strength is substantially the same as that of the magnetic field of said first coil, said first and second coils being wound independently of each other on both sides of the central portion of said reed switch, a power supply, a sensor switch means connected to said power supply through said first coil which senses a fault condition, and a warning means connected to said reed switch.
Claim 8
Dependent Claim 30 words
A warning system according to claim 5, wherein said first and second coils are connected in series with each other, and wherein one end of said second coil is grounded.
Claim 9
Dependent Claim 16 words
A warning system according to claim 5 further including a protective resistor for said reed switch.
Claim 10
Dependent Claim 117 words
A warning system comprising in combination: A pair of electromagnetic coils mounted to produce magnetomotive forces opposing one another, a reed switch having at least a pair of contacts, said contacts being opened and closed in response to the electromotive forces of said electromagnetic coils, means for energizing said coils, said means including a switch connected to at least one of said coils and being actuated in response to a fault condition to energize only one of said coils to generate an electromotive force for closing said reed contacts, said contacts remaining closed until the removal of said fault, and warning means responsive to the close of said contacts for providing a warning upon the energization thereof.
Claim 11
Dependent Claim 117 words
A warning system comprising in combination: A pair of electromagnetic coils mounted to produce magnetomotive forces opposing one another, a reed switch having at least a pair of contacts, said contacts being opened and closed in response to the electromotive forces of said electromagnetic coils, means for energizing said coils, said means including a switch connected to at least one of said coils and being actuated in response to a fault condition to energize only one of said coils to generate an electromotive force for closing said reed contacts, said contacts remaining closed until the removal of said fault, and warning means responsive to the close of said contacts for providing a warning upon the energization thereof.

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-09-15 1979-03-17 1979-09-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-09-15 1983-03-17 1983-09-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-09-15 1987-03-17 1987-09-16 $7700.00 Window Closed / Lapsed

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