Patent US4965556A successfully refreshed from Google Patents.
US4965556A
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US
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Combustion products detector having self-actuated periodic testing signal
Assignee: Bank of America Illinois
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Filing: 1988-03-08
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Granted: 1990-10-23
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Expires: 2008-03-08
Abstract
Abstract Disclosed is an improved combustion products smoke alarm that includes an electronic circuit which automatically tests the detector's operation repetitively at periodic intervals, or periodically sounds the detector's alarm to remind the occupant to manually test the detector's operation. In the preferred embodiment, this periodic testing or reminding occurs at weekly intervals. Thus, occupants living about such a smoke alarm, after experiencing this repetitive sounding of the detector's alarm for some time, will come to anticipate its sounding and notice its absence if the smoke alarm becomes inoperative.
Inventors
- 👤 James Brodecki
- 👤 William Tanguay
- 👤 Dale Fiene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:32
CPC Classifications
G; G08; G08B; G08B17/00; G08B17/10; G08B17/11; G08B29/00; G08B29/12; G08B29/14
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
233 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector the improvement which comprises: electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for periodically generating and transmitting a test pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means periodically produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said test timing means.
Claim 2
Dependent Claim
233 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector the improvement which comprises: electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for periodically generating and transmitting a test pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means periodically produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said test timing means.
Claim 3
Dependent Claim
39 words
The improved combustion products detector of claim 1 wherein each successive testing pulse is generated by said test timing means at an interval such that the test perceptible indications produced by the alarm means occur at about daily intervals.
Claim 4
Dependent Claim
39 words
The improved combustion products detector of claim 1 wherein each successive testing pulse is generated by said test timing means at an interval such that the test perceptible indications produced by the alarm means occur at about weekly intervals.
Claim 5
Dependent Claim
39 words
The improved combustion products detector of claim 1 wherein each successive testing pulse is generated by said test timing means at an interval such that the test perceptible indications produced by the alarm means occur at about biweekly intervals.
Claim 6
Dependent Claim
39 words
The improved combustion products detector of claim 1 wherein each successive testing pulse is generated by said test timing means at an interval such that the test perceptible indications produced by the alarm means occur at about quad-weekly intervals.
Claim 7
Dependent Claim
37 words
The improved combustion products detector of claim 1 wherein each successive testing pulse generated by said test timing means has a duration such that the test perceptible indication has a duration of between 1 and 5 seconds.
Claim 8
Dependent Claim
36 words
The improved combustion products detector of claim 1 wherein a first testing pulse is generated by said test timing means within ten minutes after said test timing means is initially energized by the power supply means.
Claim 9
Dependent Claim
137 words
The improved combustion products detector of claim 1 wherein said test timing means includes: periodic timing pulse generator means for producing and transmitting periodic timing pulses having a frequency that is higher than the frequency of the testing pulses generated by said test timing means; counter means, which receives and responds to the periodic timing pulses transmitted by said periodic timing pulse generator means, for counting said periodic timing pulses and in response to the count thereof repetitively and periodically producing and transmitting test time signals at the same frequency as the testing pulses generated by said test timing means; and output test pulse generator means which receives the test time signals transmitted by said counter means and in response thereto generates the testing pulses which said test timing means transmits to said electronically activatable switch means.
Claim 10
Dependent Claim
39 words
The improved combustion products detector of claim 8 wherein each successive test time signal is generated by said counter means at an interval such that the test perceptible indications produced by the alarm means occur at about daily intervals.
Claim 11
Dependent Claim
39 words
The improved combustion products detector of claim 8 wherein each successive test time signal is generated by said counter means at an interval such that the test perceptible indications produced by the alarm means occur at about weekly intervals.
Claim 12
Dependent Claim
39 words
The improved combustion products detector of claim 8 wherein each successive test time signal is generated by said counter means at an interval such that the test perceptible indications produced by the alarm means occur at about biweekly intervals.
Claim 13
Dependent Claim
39 words
The improved combustion products detector of claim 8 wherein each successive test time signal is generated by said counter means at an interval such that the test perceptible indications produced by the alarm means occur at about quad-weekly intervals.
Claim 14
Dependent Claim
40 words
The improved combustion products detector of claim 8 wherein said periodic timing pulse generator means includes a crystal controlled oscillator whose frequency of oscillation determines the frequency of the periodic timing pulses produced by said periodic timing pulse generator means.
Claim 15
Dependent Claim
75 words
The improved combustion products detector of claim 13 wherein the periodic timing pulses produced by said periodic timing pulse generator means have a frequency of 32,768 Hz, and said counter means counts 19,818,086,400 periodic timing pulses between each successive test time signal produced by said counter means, whereby the alarm means repetitively produces the test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at about weekly intervals.
Claim 16
Dependent Claim
19 words
The improved combustion products detector of claim 1 wherein said electronically activatable switch means is a semi-conductor switching device.
Claim 17
Dependent Claim
137 words
The improved combustion products detector of claim 15 wherein said test timing means includes: periodic timing pulse generator means for producing and transmitting periodic timing pulses having a frequency that is higher than the frequency of the testing pulses generated by said test timing means; counter means, which receives and responds to the periodic timing pulses transmitted by said periodic timing pulse generator means, for counting said periodic timing pulses and in response to the count thereof repetitively and periodically producing and transmitting test time signals at the same frequency as the testing pulses generated by said test timing means; and output test pulse generator means which receives the test time signals transmitted by said counter means and in response thereto generates the testing pulses which said test timing means transmits to said electronically activatable switch means.
Claim 18
Dependent Claim
40 words
The improved combustion products detector of claim 16 wherein said periodic timing pulse generator means includes a crystal controlled oscillator whose frequency of oscillation determines the frequency of the periodic timing pulses produced by said periodic timing pulse generator means.
Claim 19
Dependent Claim
75 words
The improved combustion products detector of claim 17 wherein the periodic timing pulses produced by said periodic timing pulse generator means have a frequency of 32,768 Hz, and said counter means counts 19,818,086,400 periodic timing pulses between each successive test time signal produced by said counter means, whereby the alarm means repetitively produces the test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at about weekly intervals.
Claim 20
Dependent Claim
169 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: reminder timing means, coupled to said electronic circuit means, for generating and transmitting a periodic reminding pulse to said electronic circuit means whereby in response thereto the alarm means produces a reminder perceptible indication at time intervals established by said reminder timing means, said reminder timing means including a crystal controlled oscillator for determining the frequency of the periodic reminding pulse.
Claim 21
Dependent Claim
169 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: reminder timing means, coupled to said electronic circuit means, for generating and transmitting a periodic reminding pulse to said electronic circuit means whereby in response thereto the alarm means produces a reminder perceptible indication at time intervals established by said reminder timing means, said reminder timing means including a crystal controlled oscillator for determining the frequency of the periodic reminding pulse.
Claim 22
Dependent Claim
180 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: reminder timing means, coupled to said electronic circuit means, for generating and transmitting a periodic reminding pulse to said electronic circuit means whereby in response thereto the alarm means produces a reminder perceptible indication at time intervals established by said reminder timing means, said reminder timing means also having means for generating the first reminding pulse within ten minutes after said reminder timing means is initially energized by the power supply means.
Claim 23
Dependent Claim
180 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: reminder timing means, coupled to said electronic circuit means, for generating and transmitting a periodic reminding pulse to said electronic circuit means whereby in response thereto the alarm means produces a reminder perceptible indication at time intervals established by said reminder timing means, said reminder timing means also having means for generating the first reminding pulse within ten minutes after said reminder timing means is initially energized by the power supply means.
Claim 24
Dependent Claim
249 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for generating and transmitting a periodic testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said timing means, said test timing means including a crystal controlled oscillator for determining the frequency of the periodic testing pulse.
Claim 25
Dependent Claim
249 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for generating and transmitting a periodic testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said timing means, said test timing means including a crystal controlled oscillator for determining the frequency of the periodic testing pulse.
Claim 26
Dependent Claim
277 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for generating and transmitting a periodic testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at time intervals established by said test timing means, whereby in response thereto the alarm means produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said timing means, said test timing means including a crystal controlled oscillator for determining the frequency of the periodic testing pulse, said test timing means also having means for generating the first testing pulse within ten minutes after said test timing means is initially energized by the power supply means.
Claim 27
Dependent Claim
277 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said detector, the improvement which comprises: electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for generating and transmitting a periodic testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at time intervals established by said test timing means, whereby in response thereto the alarm means produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said timing means, said test timing means including a crystal controlled oscillator for determining the frequency of the periodic testing pulse, said test timing means also having means for generating the first testing pulse within ten minutes after said test timing means is initially energized by the power supply means.
Claim 28
Dependent Claim
228 words
A combustion products detector comprising: sensor means for producing an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding said sensor means; detector responsive to the electronic signal from said sensor means for producing an output electronic signal when the concentration of combustion products about said sensor means exceeds a pre-established level; alarm means responsive to the output electronic signal from said electronic circuit means for producing a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level; power supply means for providing electrical power to energize said electronic circuit means; electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate that the concentration of combustion products about the sensor means exceeds the pre-established level; and test timing means, coupled to said electronically activatable switch means, for periodically generating and transmitting a testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means periodically produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said test timing means.
Claim 29
Dependent Claim
228 words
A combustion products detector comprising: sensor means for producing an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding said sensor means; detector responsive to the electronic signal from said sensor means for producing an output electronic signal when the concentration of combustion products about said sensor means exceeds a pre-established level; alarm means responsive to the output electronic signal from said electronic circuit means for producing a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level; power supply means for providing electrical power to energize said electronic circuit means; electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate that the concentration of combustion products about the sensor means exceeds the pre-established level; and test timing means, coupled to said electronically activatable switch means, for periodically generating and transmitting a testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means periodically produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said test timing means.
Claim 30
Dependent Claim
38 words
The combustion products detector of claim 23 wherein each successive testing pulse is generated by said test timing means at an interval such that the test perceptible indication produced by the alarm means occurs at about weekly intervals.
Claim 31
Dependent Claim
136 words
The combustion products detector of claim 23 wherein said test timing means includes: periodic timing pulse generator means for producing and transmitting periodic timing pulses having a frequency that is higher than the frequency of the testing pulses generated by said test timing means; counter means, which receives and responds to the periodic timing pulses transmitted by said periodic timing pulse generator means, for counting said periodic timing pulses and in response to the count thereof repetitively and periodically producing and transmitting test time signals at the same frequency as the testing pulses generated by said test timing means; and output test pulse generator means which receives the test time signals transmitted by said counter means and in response thereto generates the testing pulses which said test timing means transmits to said electronically activatable switch means.
Claim 32
Dependent Claim
38 words
The combustion products detector of claim 25 wherein each successive test time signal is generated by said counter means at an interval such that the test perceptible indications produced by the alarm means occur at about biweekly intervals.
Claim 33
Dependent Claim
443 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said electronic circuit means, the power supply means being continuously supplied with electrical power by an alternating current electrical power source, the improvement which comprises: timing signal means coupled to the power supply means for transmitting an alternating current timing signal at a frequency controlled by the frequency of the alternating current electrical power source; electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for periodically generating and transmitting a testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means periodically produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said test timing means, said test timing means including: periodic timing pulse generator means for producing and transmitting periodic timing pulses having a frequency that is higher than the frequency of the testing pulses generated by said test timing means, said periodic timing pulse generator means having a pulse generation circuit that receives the alternating current timing signal transmitted by the power supply means and produces the periodic timing pulses in response thereto; counter means, which receives and responds to the periodic timing pulses transmitted by said periodic timing pulse generator means, for counting said periodic timing pulses and in response to the count thereof repetitively and periodically producing and transmitting test time signals at the same frequency as the testing pulses generated by said test timing means; and output test pulse generator means which receives the test time signals transmitted by said counter means and in response thereto generates the testing pulses which said test timing means transmits to said electronically activatable switch means.
Claim 34
Dependent Claim
443 words
In a combustion products detector having sensor means that produces an electronic signal indicative of the concentration of combustion products present in the atmosphere surrounding the sensor means, electronic circuit means responsive to the electronic signal from the sensor means that produces an output electronic signal when the concentration of combustion products about the sensor means exceeds a pre-established level, alarm means responsive to the output electronic signal from the electronic circuit means that produces a perceptible indication when the concentration of combustion products about the sensor means exceeds the pre-established level, and power supply means that provides electrical power to energize said electronic circuit means, the power supply means being continuously supplied with electrical power by an alternating current electrical power source, the improvement which comprises: timing signal means coupled to the power supply means for transmitting an alternating current timing signal at a frequency controlled by the frequency of the alternating current electrical power source; electronically activatable switch means, coupled to the sensor means, for generating a test electronic signal transmitted by the sensor means to the electronic circuit means to simulate a concentration of combustion products about the sensor means exceeding the pre-established level; and test timing means, coupled to said electronically activatable switch means, for periodically generating and transmitting a testing pulse to said electronically activatable switch means to activate said switch means thereby causing the test electronic signal to be transmitted at periodic time intervals established by said test timing means, whereby in response thereto the alarm means periodically produces a test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at time intervals established by said test timing means, said test timing means including: periodic timing pulse generator means for producing and transmitting periodic timing pulses having a frequency that is higher than the frequency of the testing pulses generated by said test timing means, said periodic timing pulse generator means having a pulse generation circuit that receives the alternating current timing signal transmitted by the power supply means and produces the periodic timing pulses in response thereto; counter means, which receives and responds to the periodic timing pulses transmitted by said periodic timing pulse generator means, for counting said periodic timing pulses and in response to the count thereof repetitively and periodically producing and transmitting test time signals at the same frequency as the testing pulses generated by said test timing means; and output test pulse generator means which receives the test time signals transmitted by said counter means and in response thereto generates the testing pulses which said test timing means transmits to said electronically activatable switch means.
Claim 35
Dependent Claim
84 words
The improved combustion products detector of claim 27 wherein the periodic timing pulses produced by the periodic timing pulse generator means in response to the alternating current electrical power source have a frequency of 60 Hz, and said counter means counts 36,288,000 periodic timing pulses between each successive test time signal produced by said counter means, whereby the alarm means repetitively produces the test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at about weekly intervals.
Claim 36
Dependent Claim
84 words
The improved combustion products detector of claim 27 wherein the periodic timing pulses produced by the periodic timing pulse generator means in response to the alternating current electrical power source have a frequency of 120 Hz, and said counter means counts 72,576,000 periodic timing pulses between each successive test time signal produced by said counter means, whereby the alarm means repetitively produces the test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at about weekly intervals.
Claim 37
Dependent Claim
19 words
The improved combustion products detector of claim 27 wherein said electronically activatable switch means is a semiconductor switching device.
Claim 38
Dependent Claim
84 words
The improved combustion products detector of claim 30 wherein the periodic timing pulses produced by the periodic timing pulse generator means in response to the alternating current electrical power source have a frequency of 60 Hz, and said counter means counts 36,288,000 periodic timing pulses between each successive test time signal produced by said counter means, whereby the alarm means repetitively produces the test perceptible indication that the concentration of combustion products about the sensor means exceeds the per-established level at about weekly intervals.
Claim 39
Dependent Claim
84 words
The improved combustion products detector of claim 30 wherein the periodic timing pulses produced by the periodic timing pulse generator means in response to the alternating current electrical power source have a frequency of 120 Hz, and said counter means counts 72,576,000 periodic timing pulses between each successive test time signal produced by said counter means, whereby the alarm means reptitively produces the test perceptible indication that the concentration of combustion products about the sensor means exceeds the pre-established level at about weekly intervals.
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