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US3846794A Expired / Lapsed US ⏱️ 0.0 years remaining

Alarm retransmission system

Assignee: Baker Industries Inc
•
Filing: 1973-03-15
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Granted: 1974-11-05
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Expires: 1993-03-15
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Abstract

Abstract An AC alarm retranmission system connecting a plurality of receiver units on a single DC circuit such as a McCulloh circuit. When an alarm retransmission is initiated, all of the receiver units will receive a first signal which is a basic signal transmitted at a frequency so chosen to minimize noise interference. The first signal is achieved by switching the basic signal on and off at a frequency which will correspond with that of a tone module connected in the addressed or selected receiver unit. Although each receiver unit is capable of receiving the basic signal, only the selected receiver unit will be capable of receiving a second signal. The second signal is the basic signal transmitted in code by means of a Gamewell Coder in a manner well known in the art, to provide information as to the initial source of the alarm.

Inventors

  • 👤 Nay T Le
  • 👤 D Hadden

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 05:19
CPC Classifications
G; G08; G08B; G08B25/00; G08B25/01; G08B25/04; G08B25/045

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 246 words
An alarm retransmission system for use in a McCulloh circuit for presignaling a selected receiver unit by a first signal and subsequently providing additional data by a second signal to the selected receiver unit comprising: first means for transmitting a basic signal at a preselected frequency in response to an alarm event; a command unit electrically connected to said first means capable of modulating the basic signal at a plurality of predetermined frequencies thereby forming a first signal; a coder unit electrically connected to said first means capable of modulating the basic signal in a code thereby forming a second signal, said code being indicative of the origin of the alarm event; a plurality of receiver units, each of said receiver units being connected in series in a single circuit, each of said receiver units being adapted to receive the first signal and the second signal; a tone module electrically connected in each of said receiver units, each of said tone modules having a different frequency range corresponding to a predetermined frequency output of said command unit; and a gate unit for receiving the additional data, electrically coupled with each of said tone modules in each of said receiver units and activated in response to the second signal within a predetermined time after the appropriate first signal has been received by said appropriate receiver unit, said appropriate receiver unit including said tone module of the corresponding frequency range as the preselected frequency of said command unit.
Claim 2
Dependent Claim 246 words
An alarm retransmission system for use in a McCulloh circuit for presignaling a selected receiver unit by a first signal and subsequently providing additional data by a second signal to the selected receiver unit comprising: first means for transmitting a basic signal at a preselected frequency in response to an alarm event; a command unit electrically connected to said first means capable of modulating the basic signal at a plurality of predetermined frequencies thereby forming a first signal; a coder unit electrically connected to said first means capable of modulating the basic signal in a code thereby forming a second signal, said code being indicative of the origin of the alarm event; a plurality of receiver units, each of said receiver units being connected in series in a single circuit, each of said receiver units being adapted to receive the first signal and the second signal; a tone module electrically connected in each of said receiver units, each of said tone modules having a different frequency range corresponding to a predetermined frequency output of said command unit; and a gate unit for receiving the additional data, electrically coupled with each of said tone modules in each of said receiver units and activated in response to the second signal within a predetermined time after the appropriate first signal has been received by said appropriate receiver unit, said appropriate receiver unit including said tone module of the corresponding frequency range as the preselected frequency of said command unit.
Claim 3
Dependent Claim 15 words
An alarm retransmission system as in claim 1 wherein said first means is an oscillator.
Claim 4
Dependent Claim 18 words
An alarm retransmission system as in claim 2 wherein said oscillator transmits a basic signal of 15 Hz.
Claim 5
Dependent Claim 16 words
An alarm retransmission system as in claim 1 wherein said coder unit is a Gamewell Coder.
Claim 6
Dependent Claim 28 words
An alarm retransmission system of claim 1 wherein said coder unit modulates the basic signal at a frequency outside the frequency range of all of said tone modules.
Claim 7
Dependent Claim 198 words
An alarm retransmission system for use in a McCulloh circuit for presignaling a selected receiver unit by a first signal and subsequently providing additional data by a second signal to the selected receiver unit comprising: first means for transmitting a first signal on a circuit in response to an alarm location, said first signal comprising a first carrier signal modulated at a predetermined frequency; second means for transmitting a second signal on the same circuit, said second signal comprising a second carrier signal modulated in accordance with a code, the code being indicative of the alarm location; a plurality of receiver units being connected in series in the same circuit, each of said receiver units including a tone module of a preselected frequency range, each of said tone modules having a unique preselected frequency range; aNd a gate unit for receiving the additional data, electrically coupled to each of said tone modules in each of said receiver units, said gate unit being activated in response to said second signal only within a predetermined time after transmission of said first signal at the predetermined frequency corresponding to the frequency range of said tone module associated with said gate unit.
Claim 8
Dependent Claim 198 words
An alarm retransmission system for use in a McCulloh circuit for presignaling a selected receiver unit by a first signal and subsequently providing additional data by a second signal to the selected receiver unit comprising: first means for transmitting a first signal on a circuit in response to an alarm location, said first signal comprising a first carrier signal modulated at a predetermined frequency; second means for transmitting a second signal on the same circuit, said second signal comprising a second carrier signal modulated in accordance with a code, the code being indicative of the alarm location; a plurality of receiver units being connected in series in the same circuit, each of said receiver units including a tone module of a preselected frequency range, each of said tone modules having a unique preselected frequency range; aNd a gate unit for receiving the additional data, electrically coupled to each of said tone modules in each of said receiver units, said gate unit being activated in response to said second signal only within a predetermined time after transmission of said first signal at the predetermined frequency corresponding to the frequency range of said tone module associated with said gate unit.
Claim 9
Dependent Claim 16 words
An alarm retransmission system as in claim 6 wherein said first and second means are oscillators.
Claim 10
Dependent Claim 28 words
An alarm retransmission system as in claim 6 wherein each second means modulates the second signal at a frequency outside the range of all of said tone modules.
Claim 11
Dependent Claim 266 words
An alarm retransmission system for use in a McCulloh circuit for presignaling a selected receiver unit by a first signal and subsequently providing additional data by a second signal to the selected receiver unit comprising: first means for transmitting a first basic signal at a preselected frequency in response to an alarm event; a command unit electrically connected to said first means and capable of modulating the first basic signal at a plurality of predetermined frequencies, thereby forming a first signal, each predetermined frequency of said command unit corresponding to a particular location on the McCulloh circuit; a Gamewell Coder unit electrically connected to said first means capable of modulating a second basic signal in a code thereby forming a second signal, said code being representative of the location of the origin of the alarm event; a plurality of receiver units, each of said receiver units connected in series at particular locations in the McCulloh circuit, each of said receiver units adapted to receive the first and second signals; a tone module having a predetermined frequency range, electrically connected in each of said receiver units, each tone module having a frequency range determined by the location of said receiver unit, and corresponding to a frequency of said command unit; and a gate unit for receiving the additional data electrically coupled to each of said tone modules and activated by the first signal when modulated at the frequency indicative of the location of the tone module and remaining activated within a predetermined time after the first signal in response to the second signal after being initially activated.
Claim 12
Dependent Claim 266 words
An alarm retransmission system for use in a McCulloh circuit for presignaling a selected receiver unit by a first signal and subsequently providing additional data by a second signal to the selected receiver unit comprising: first means for transmitting a first basic signal at a preselected frequency in response to an alarm event; a command unit electrically connected to said first means and capable of modulating the first basic signal at a plurality of predetermined frequencies, thereby forming a first signal, each predetermined frequency of said command unit corresponding to a particular location on the McCulloh circuit; a Gamewell Coder unit electrically connected to said first means capable of modulating a second basic signal in a code thereby forming a second signal, said code being representative of the location of the origin of the alarm event; a plurality of receiver units, each of said receiver units connected in series at particular locations in the McCulloh circuit, each of said receiver units adapted to receive the first and second signals; a tone module having a predetermined frequency range, electrically connected in each of said receiver units, each tone module having a frequency range determined by the location of said receiver unit, and corresponding to a frequency of said command unit; and a gate unit for receiving the additional data electrically coupled to each of said tone modules and activated by the first signal when modulated at the frequency indicative of the location of the tone module and remaining activated within a predetermined time after the first signal in response to the second signal after being initially activated.
Claim 13
Dependent Claim 27 words
An alarm retransmission system as in claim 9 wherein said Gamewell Coder modulates the second signal at a frequency outside the range of all said tone modules.
Claim 14
Dependent Claim 22 words
An alarm retransmission system as in claim 9 wherein said first means is an oscillator operating at a frequency of 15 hertz.

References Cited (Backward Citations)

US3430199A Cited
US3613004A Cited
US3314051A Cited
US3290597A Cited
US3634824A Cited
US3694810A Cited
US3716790A Cited
US3678512A Cited
US3729680A Cited
US3718768A Cited
US3754215A Cited
US3758860A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-11-04 1978-05-06 1978-11-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-11-04 1982-05-06 1982-11-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-11-04 1986-05-06 1986-11-05 $7700.00 Window Closed / Lapsed

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