Combustion products detector having self-actuated periodic testing signal

• US 4,965,556 A
• Filed: 03/08/1988
• Issued: 10/23/1990
• Est. Priority Date: 03/08/1988
• Status: Expired due to Term

• Current Assignee: Maple Chase Company (Schneider Electric SE)
• Original Assignee: Seat SA (Volkswagen AG)
• Inventors: Fiene, Dale, Brodecki, James, Tanguay, William
• Primary Examiner(s): Orsino, Joseph A.
• Assistant Examiner(s): Jackson, Jill
• Application Number:
  US07/165,611
• Time in Patent Office: 959 Days
• Field of Search: 340/628, 340/514, 340/515, 340/516, 340/629, 340/630, 250/573-575, 250/577, 356/439, 356/438
• US Class Current: 340/628
• CPC Class Codes: G08B 17/11 using an ionisation chamber for detecting smoke or gas
• CPC Class Codes: G08B 29/14 checking the detection circuits

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.

Claims

1. 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.

2. 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.

3. 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.

4. 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.

5. 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.

6. 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.

7. 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.

8. 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.

9. 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.

10. 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.

11. 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.

12. 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.

13. 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.

14. 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.

15. The improved combustion products detector of claim 1 wherein said electronically activatable switch means is a semi-conductor switching device.

16. 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.

17. 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.

18. 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.

19. 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.

20. 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.

21. 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.

22. 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.

23. 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.

24. 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.

25. 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.

26. 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.

27. 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.

28. 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.

29. 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.

30. The improved combustion products detector of claim 27 wherein

said electronically activatable switch means is a semiconductor switching device.

31. 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.

32. 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.