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US4839918A Expired / Lapsed US ⏱️ 0.0 years remaining

Switching system between cordless telephone and ordinary telephone

Assignee: NEC Corp
•
Filing: 1987-09-16
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Granted: 1989-06-13
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Expires: 2007-09-16
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Abstract

Abstract A system for enabling switching between a cordless telephone, including a fixed unit and a portable unit, and an ordinary telephone which may be connected to the cordless telephone through a subscriber network. The portable unit portion of the cordless telephone may be connected to an ordinary telephone, even when power is not available to the fixed unit, by providing selective switching to the subscriber network, which provides power to the telephone unit which is part of the fixed unit.

Inventors

  • 👤 Mamoru Hata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 20:15
CPC Classifications
H; H04; H04M; H04M9/00; H04M1/00; H04M1/72; H04M1/725; H04M19/00

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 181 words
A switching system for selectively connecting a cordless telephone and telephone unit, comprising: a fixed unit, on a first side, and a portable unit, on a second side, connected to each other by radio; a telephone unit provided on said first side; an internal line applied with a D.C. voltage from a power source which is applied to said fixed unit; a first switch responsive to a first switching control signal for selectively connecting said telephone unit to one of a subscriber line and said internal line, said subscriber line being connected to a telephone network; a second switch responsive to a second switching control signal for selectively connecting said fixed unit to one of said subscriber line and said internal line; and switching control means responsive to a switching command signal for generating said first and second switching control signals, said telephone unit receiving power from one of said internal line and said subscriber line in accordance with said first and second switching control signals such that said telephone unit continues to operate even during failure of said power source.
Claim 2
Dependent Claim 181 words
A switching system for selectively connecting a cordless telephone and telephone unit, comprising: a fixed unit, on a first side, and a portable unit, on a second side, connected to each other by radio; a telephone unit provided on said first side; an internal line applied with a D.C. voltage from a power source which is applied to said fixed unit; a first switch responsive to a first switching control signal for selectively connecting said telephone unit to one of a subscriber line and said internal line, said subscriber line being connected to a telephone network; a second switch responsive to a second switching control signal for selectively connecting said fixed unit to one of said subscriber line and said internal line; and switching control means responsive to a switching command signal for generating said first and second switching control signals, said telephone unit receiving power from one of said internal line and said subscriber line in accordance with said first and second switching control signals such that said telephone unit continues to operate even during failure of said power source.
Claim 3
Dependent Claim 19 words
A switching system as claimed in claim 1, further comprising first means for manually generating said switching command signal.
Claim 4
Dependent Claim 26 words
A switching system as claimed in claim 2, wherein said portable unit comprises second means, different from said first means, for generating said switching command signal.
Claim 5
Dependent Claim 109 words
A switching system for selectively connecting a cordless telephone and a telephone unit, comprising: a fixed unit and a portable unit provided in said cordless telephone and radio-connected to each other; a power source for supplying electric power to said fixed unit; an internal connection line connected to said power source; a first switch responsive to a first switching signal for selectively connecting said telephone unit to one of a subscriber line connected to a telephone network and said internal connection line; and a second switch responsive to a second switching signal for selectively connecting said fixed unit to one of said subscriber line and said internal connection line.
Claim 6
Dependent Claim 109 words
A switching system for selectively connecting a cordless telephone and a telephone unit, comprising: a fixed unit and a portable unit provided in said cordless telephone and radio-connected to each other; a power source for supplying electric power to said fixed unit; an internal connection line connected to said power source; a first switch responsive to a first switching signal for selectively connecting said telephone unit to one of a subscriber line connected to a telephone network and said internal connection line; and a second switch responsive to a second switching signal for selectively connecting said fixed unit to one of said subscriber line and said internal connection line.
Claim 7
Dependent Claim 20 words
A switching system as claimed in claim 4, further comprising means for manually generating said first and second switching signals.
Claim 8
Dependent Claim 22 words
A switching system as claimed in claim 4, wherein said portable unit comprises means for generating said first and second switching signals.
Claim 9
Dependent Claim 54 words
A switching system as claimed in claim 4, wherein both of said first and second switches operate in response to said first and second switching signals, respectively, and wherein said first and second switching signals are either manually generated or remotely generated signals are either manually generated or remotely generated from said portable unit.
Claim 10
Dependent Claim 21 words
A switching system as claimed in claim 7, wherein each of said first and second switches comprises a self-holding type relay.
Claim 11
Dependent Claim 33 words
A switching system as claimed in claim 4, wherein said first and second switches are selectively controllable so as to connect both said telephone unit and said fixed unit to said subscriber line.
Claim 12
Dependent Claim 34 words
A switching system as claimed in claim 4, wherein said first and second switches are selectively controllable so as to connect both said telephone unit and said fixed unit to said internal connection line.
Claim 13
Dependent Claim 29 words
A switching system as claimed in claim 4, wherein said first and second switches are selectively controllable so as to connect only said telephone unit to said subscriber line.
Claim 14
Dependent Claim 29 words
A switching system as claimed in claim 4, wherein said first and second switches are selectively controllable so as to connect only said fixed unit to said subscriber line.
Claim 15
Dependent Claim 125 words
A switching method of switching between a telephone unit and a cordless telephone, said cordless telephone including a fixed unit and a portable unit radio-connected to each other, said method comprising the steps of: supplying electric power source to said fixed unit; connecting said telephone unit through a first switch to one of a subscriber line connected to a telephone network and a connection line connected to said power source; connecting said fixed unit through a second switch to one of said subscriber line and said connection line; and operating said first and second switches such that said telephone unit receives power from one of said connection line and said subscriber line, said telephone unit continuing to operate even during failure of said power source.
Claim 16
Dependent Claim 125 words
A switching method of switching between a telephone unit and a cordless telephone, said cordless telephone including a fixed unit and a portable unit radio-connected to each other, said method comprising the steps of: supplying electric power source to said fixed unit; connecting said telephone unit through a first switch to one of a subscriber line connected to a telephone network and a connection line connected to said power source; connecting said fixed unit through a second switch to one of said subscriber line and said connection line; and operating said first and second switches such that said telephone unit receives power from one of said connection line and said subscriber line, said telephone unit continuing to operate even during failure of said power source.
Claim 17
Dependent Claim 23 words
A method as claimed in claim 13, further comprising the step of manually generating control signals for switching said first and second switches.
Claim 18
Dependent Claim 26 words
A method as claimed in claim 13, further comprising the step of generating control signals for switching said first and second switches from said portable unit.
Claim 19
Dependent Claim 37 words
A method as claimed in claim 13, further comprising the step of supplying first and second control signals to said first and second switches to connect both said telephone unit and fixed unit to said subscriber line.
Claim 20
Dependent Claim 37 words
A method as claimed in claim 13, further comprising the step of supplying first and second control signals to said first and second switches to connect both said telephone unit and fixed unit to said connection line.
Claim 21
Dependent Claim 34 words
A method as claimed in claim 13, further comprising the step of supplying first and second control signals to said first and second switches to connect only said telephone unit to said subscriber line.
Claim 22
Dependent Claim 34 words
A method as claimed in claim 13, further comprising the step of supplying first and second control signals to said first and second switches to connect only said fixed unit to said subscriber line.

References Cited (Backward Citations)

US4640987A Cited
US4706274A Cited
US4731812A Cited
US4691338A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-06-12 1992-12-12 1993-06-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-06-12 1996-12-12 1997-06-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-06-12 2000-12-12 2001-06-13 $7700.00 Window Closed / Lapsed

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