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US 4,065,759 AGranted
Smoke detector
OwnerTheodore E. Handinginventor
Life of this patent
Estimating the term…
Abstract
A smoke detector working on the principal of interference of light between an L.E.D. source and a phototransistor receiver detects differences in smoke emission regardless of the color of the smoke. A pulsating power supply automatically turns the power to the unit on and off every thirty seconds so that the life of the unit is extended and energy is conserved. When a hazardous smoke condition exists, the unit produces rapidly interrupted alarm signals. A warning signal which is different than the alarm signal draws attention to an optoelectronic system malfunction or a power supply voltage drop below a preset level.
Claims17
A smoke detector operating on the principle of interference of light by smoke comprising:
- a. a smoke test chamber;
- b. a source of D.C. power including an output and a ground;
- c. a pulsed D.C. power supply including an input operationally connected to the source of D.C. power and an output;
- d. a pulsed D.C. power supply regulator having an input operationally connected to the output of the pulsed D.C. power supply, and an output;
- e. a smoke sensing means including a source of light and a light receiver in fluid communication with the smoke test chamber and operationally connected to the output from the pulsed D.C. power supply regulator;
- f. an alarm trigger having an input operationally connected to the output from the pulsed D.C. power supply regulator and to the output from the smoke sensing means;
- g. an alarm pulser having an input operationally connected to the outputs from the alarm trigger and the source of D.C. power;
- and
- h. an alarm means having an input operationally connected to the output from the alarm pulser.
6 more elements
In a smoke detector as set forth in claim 3 wherein the power supply pulser comprises:
- a. a first capacitor operationally connected at one plate to the other end of said first resistor;
- b. a second capacitor operationally connected at one plate to the other plate of said first capacitor and having its other plate operationally connected to ground;
- c. a first transistor having one junction operationally connected to the other end of said first resistor and having its base connected to the one end of the second resistor;
- d. a second transistor having one junction operationally connected to the one end of the second resistor and having its base connected to the other junction of the first transistor;
- e. a third resistor having one end operationally connected to the other junction of the second transistor and its other end operationally connected to the other plate of said first capacitor;
- and
- f. a fourth resistor having one end operationally connected to the other end of the third resistor and its other end operationally connected to ground;
- whereby the polarities associated with the operational connection of the first and second transistors in the power supply pulser are such as to produce pulsation of the power supply.
5 more elements
A smoke detector operating on the principle of light interference by smoke, having a pulsed power supply for conserving energy, a pulsed alarm circuit, a warning of a short or opening in the smoke detector circuit, and a low A.C. supply voltage warning and automatic switchover to battery circuit, comprising:
- 1. a transformer operationally connected to a source of A.C. power and having secondary output terminals;
- 2. a full-wave bridge rectifier having input terminals operationally connected to the secondary output terminals of the transformer;
- 3. a power supply capacitor operationally connected across the output terminals of the bridge rectifier to ground;
- 4. a battery in series connection with a diode and both operationally connected across the output terminals of the bridge rectifier;
- 5. a first resistor operationally connected at one end to the high output terminal of said bridge rectifier;
- a. a first capacitor operationally connected at one plate to the other end of said first resistor;
- b. a second capacitor operationally connected at one plate to the other plate of said first capacitor and having its other plate operationally connected to ground;
- c. a first PNP transistor having its emitter operationally connected to the other end of said first resistor and its base connected to the output of the power supply pulser;
- d. a first NPN transistor having its base operationally connected to the collector of the first PNP transistor and its collector operationally connected to the output of the power supply pulser;
- e. a third resistor having one end operationally connected to the emitter of the first NPN transistor and its other end operationally connected to the other plate of said first capacitor;
- f. a fourth resistor having one end operationally connected to the other end of the third resistor and its other end operationally connected to ground;
- g. a second PNP transistor having its emitter operationally connected to the source of D.C. power, its base operationally connected to the other end of the second resistor and its collector operationally connected to the output from said power supply switcher;
- h. a fifth resistor operationally connected at one end to the output from the pulsed D.C. power supply;
- i. a second NPN transistor having its collector operationally connected to the output from the pulsed D.C. power supply, its base operationally connected to the other end of said fifth resistor and its emitter operationally connected to the output from the pulsed D.C. power supply regulator;
- j. a Zener diode having its cathode operationally connected to the other end of said fifth resistor and its anode operationally connected to ground;
- k. a sixth resistor having one end operationally connected to the output from the pulsed D.C. power supply voltage regulator;
- l. a first potentiometer having one end operationally connected to the other end of the sixth resistor;
- m. a first L.E.D. having its anode operationally connected to the other end of the first potentiometer and its cathode operationally connected to ground and mounting in the lower end of the bore in the housing operationally focused to shine light up the axis of said bore;
- n. a first diode having its anode operationally connected to the output from the pulsed D.C. power supply regulator;
- o. a seventh resistor having one end operationally connected to the cathode of said first diode;
- p. a light sensor including an output having its input operationally connected to the other end of said seventh resistor and mounting in the upper end of the bore in the housing operationally focused to receive light from down the axis of said bore;
- q. an amplifier having a first input operationally connected to the other end of said seventh resistor and a second input operationally connected to the output from said light sensor;
- r. an NPN phototransistor having its collector operationally connected to the input to and its emitter operationally connected to the output from said light sensor;
- s. a third NPN transistor having its collector operationally connected to first input to said amplifier and to the output therefrom and its base operationally connected to the output from said light sensor;
- t. a first diode having its anode operationally connected to the output from the pulsed D.C. power supply voltage regulator;
- u. an eighth resistor having one end operationally connected to the output from the amplifier;
- v. a ninth resistor having one end operationally connected to the cathode of the first diode;
- w. a third PNP transistor having its emitter operationally connected to the other end of the eighth resistor and its base operationally connected to the other end of the ninth resistor;
- x. a fourth NPN transistor having its collector operationally connected to the other end of the ninth resistor, its base operationally connected to the collector of the third PNP transistor and its emitter operationally connected to one end of a tenth resistor the other end of which connects to ground and to the output from the alarm trigger;
- y. an eleventh resistor having one end operationally connected to the input to the alarm pulser;
- z. a third capacitor having one plate operationally connected to the other end of the eleventh resistor;
- aa. a twelfth resistor having one end operationally connected to the other plate of the third capacitor;
- bb. a fourth PNP transistor having its emitter operationally connected to the source of D.C. power and its collector operationally connected to the other end of the twelfth resistor;
- cc. a fifth PNP transistor having its emitter operationally connected to the base of the fourth PNP transistor, its collector operationally connected to the other end of the twelfth resistor and to the output from the alarm pulser;
- dd. a thirteenth resistor having one end operationally connected to the base of said fifth PNP transistor;
- ee. a fifth NPN transistor having its base operationally connected to the other end of the eleventh resistor, its collector operationally connected to the other end of the thirteenth resistor and its emitter operationally connected to ground;
- ff. a magnetic horn having its input operationally connected to the output of the alarm pulser and its output operationally connected to ground;
- gg. a fourteenth resistor having one end operationally connected to the anode of the first diode;
- hh. a second L.E.D. having its anode operationally connected to the other end of the fourteenth resistor and its cathode operationally connected to ground;
- ii. a sixth PNP transistor having its emitter operationally connected to the anode of the first L.E.D., its base operationally connected to the anode of the second L.E.D. and its collector operationally connected to the output from the open-short supervisor;
- jj. a sixth NPN transistor having its emitter operationally connected to the base of the sixth PNP transistor, its base operationally connected to the emitter of the same and its collector operationally connected to the output from the open-short supervisor;
- kk. a fifteenth resistor having one end operationally connected to the output from the pulsed D.C. power supply and its other end operationally connected to the output from the open-short supervisor;
- ll. a second diode having its cathode operationally connected to the output from the open-short supervisor;
- mm. a third diode having its cathode operationally connected to the output from the open-short supervisor;
- nn. a second potentiometer having one end operationally connected to the anode of the third diode and its other end to ground;
- oo. a sixteenth resistor having one end operationally connected to the output from the pulsed D.C. power supply and its other end operationally connected to the anode of the third diode;
- pp. a seventeenth resistor having one end operationally connected to the anode of the third diode;
- qq. a fourth diode having its cathode operationally connected to the other end of the seventeenth resistor;
- rr. an eighteenth resistor having one end operationally connected to the other end of the seventeenth resistor;
- ss. a nineteenth resistor having one end operationally connected to the output of the pulsed D.C. power supply regulator;
- tt. a seventh PNP transistor having its emitter operationally connected to the other end of the eighteenth resistor and its base operationally connected to the other end of the nineteenth resistor;
- uu. a seventh NPN transistor having its collector operationally connected to the base of the seventh PNP transistor and its base operationally connected to the collector of the same;
- vv. a twentieth resistor having one end operationally connected to the emitter of the seventh NPN transistor and its other end operationally connected to ground;
- ww. a fifth diode having its anode operationally connected to the base of the seventh PNP transistor and its cathode operationally connected with the output from the warning trigger;
- xx. a fifth capacitor having one plate operationally connected to the base of the seventh PNP transistor and its other plate operationally connected to ground;
- yy. a sixth diode having its anode operationally connected to the collector of the fifth PNP transistor;
- zz. a sixth capacitor having one plate operationally connected to the cathode of the sixth diode and to the anode of the fourth diode and its other plate operationally connected to ground;
- aaa. a twenty-first resistor operationally connected at one end to the cathode of the sixth diode;
- bbb. a seventh diode having its anode operationally connected to the other end of the twenty-first resistor and its cathode operationally connected to the other end of the first resistor;
- and
- ccc. an eighth diode having its cathode operationally connected to the collector of the fifth PNP transistor and its anode operationally connected to ground.
58 more elements
Dependencies are inferred from the claim text.