CA1290385C - Programmable light activated emergency marking system - Google Patents
Programmable light activated emergency marking systemInfo
- Publication number
- CA1290385C CA1290385C CA000601294A CA601294A CA1290385C CA 1290385 C CA1290385 C CA 1290385C CA 000601294 A CA000601294 A CA 000601294A CA 601294 A CA601294 A CA 601294A CA 1290385 C CA1290385 C CA 1290385C
- Authority
- CA
- Canada
- Prior art keywords
- light
- marking system
- illumination
- activated emergency
- programmable light
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000005286 illumination Methods 0.000 claims abstract description 15
- 230000004913 activation Effects 0.000 claims abstract description 6
- 239000000203 mixture Substances 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 238000001514 detection method Methods 0.000 claims 5
- 239000004065 semiconductor Substances 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 4
- 238000009434 installation Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 206010034960 Photophobia Diseases 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 208000013469 light sensitivity Diseases 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B39/00—Circuit arrangements or apparatus for operating incandescent light sources
- H05B39/04—Controlling
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B39/00—Circuit arrangements or apparatus for operating incandescent light sources
- H05B39/09—Circuit arrangements or apparatus for operating incandescent light sources in which the lamp is fed by pulses
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
- H05B47/10—Controlling the light source
- H05B47/105—Controlling the light source in response to determined parameters
- H05B47/11—Controlling the light source in response to determined parameters by determining the brightness or colour temperature of ambient light
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
- H05B47/10—Controlling the light source
- H05B47/16—Controlling the light source by timing means
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection
Landscapes
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
ABSTRACT
A programmable light activated emergency marking system operates from rechargeable or non-rechargeable batteries or a rectified AC current,upon reduction of surrounding light levels below that of a set threshold level. Included are provisions for varying the threshold level of light required for activation as well as the length of time the system provides flashing illumination once the said system has been activated.
A programmable light activated emergency marking system operates from rechargeable or non-rechargeable batteries or a rectified AC current,upon reduction of surrounding light levels below that of a set threshold level. Included are provisions for varying the threshold level of light required for activation as well as the length of time the system provides flashing illumination once the said system has been activated.
Description
Backqro,und of the_Inve,,nt.,iQn The present invention relates to emergency mark1ng systems operating from rechargeable or non-rechargeable batkeries or a recti~ied AC current upon reduc~ion of light levels. More specifically, it relates to emergency mark1ng systems providing a flashing illumination system operated from alkali bfltteries and capable of providing a Pre-set variable number of hours of flashing illumination in the event of surrounding light levels falling below a pre-set variable level. Although the system is described primarily in terms of ~lashing illuminat10n, the principle is equally applicable to non-flashing illumination by simple modification.
Summarv of the Invention It is common for battery-Powered emergency marking systems to be activated by an interruption of AC power. Signs of this type ignore the possibility that although AC current is being suppl;ed, burnt out room light bulbs or brown out condit;ons (when line voltage is less than the rated level) can cause the area where the sign is placed to be in darkness, thereby rendering the unlit sign v1rtually invisible and vit1ating its whole intent and purpose. As well, these type of signs generally are associated with high operating expenses: for installation they must be hardwired to an AC current, and for operation electricity and malntenance (eg. incandescent bulb replacement) must be supplied.
. .. ~
~ ;. t ~
,, ~ , ,., ., . ~
1 2 ~
It is there~ore the primary object of the present invention to Provide an emergency markin~ sYstem wh1ch interactively responds to varlous surrounding light levels (ie.
light activated) so that the system becomes operational when it ls needad (;e. when light levels fall below a minimum threshold level.) Another ob~ject of the invention is to allow the length of time of operation, as well as the minimum threshold light level required for activation, to be programmable so that the system can give optimum performance in all situations.
Another object of the invention is to provide a highly visible sign with minimal d;stortion by generally distributing the light evenlY over the face of the sign.
A further object of the invention is to reduce the cost and provide an extremely long virtu~lly maintenance-free life for the system by minimizlng both the clrcuit complexity and the number of components in the system.
The above and other objects of the ~nvention are realized through the use of a li~ht sensor, control board, and light source.
The present device uses light em1tting diodes to provide a high visibility, low power source of illumination which has a long operating life. By connecting the light emitting diodes in parallel the voltage requirements are reduced to a minimum. In addition, the light emltting diodes cause a wide dispersion of the light so as to greatly reduce the light "highs ~ ,., ";.~
~ 8.~
and lows" on the face ef the sign as compared to those produced by incandescent bu 1 bs .
The present device uses a phot.otranslstor connecked to the control circuit as the light sensor. The phototransistor gain is controlled by a variable resistor, so that the threshold level oF light for activation can be changed in order to best suit the requirements of the system's eventual physical location.
When this minimum threshold level is reached, the system is activated and the light em;tting d;odes flash until either the system is reset or the pre-set time per-iod has elapsed.
In addition, the present device uses a fourteen stage ripple counter integrated circuit connected to the external circuitry via a shorting Plug in order to program the length of time for activation. In many situations, it is desirable ko have the sYstem cease operaking before the batteries are depleted.
Therefore, by placing the shorting plug in one of the three possible posit;ons supplied bY the present device, either one half-hour, one hour, or two hours of operation can be selected.
Th;s programmable abil;ty greatly increases the utility of the system, since the battery is not completely drained the first time the system is activated.
The above and other objects, features, and advantages of the present ;nvention will become more aPparent from the following detailed descr;pt;on, wherein I have shown and described only the preferred embodiment of the lnvention, simply by way of ;llustrakion of the best mode contemplated by me of . ~, . . ..
~?9~;385 carrying out mY invention. As will bs realized, the invention is capable oF differen~ embodiments, and capable of modlf1cation in various obvious respects, all without dePartin~ from the invention. Accordingly, the drawings and descripk;on are to be regarded as illustrative in nature, and not as restrictive.
Brief DescriDtion oF t e Drawin~s Figure 1 is a c;rcuit diagram of the control board for the programmable light-activated emergency marking system;
Figure 2 is a logic diagram of the 4093 Integrated circuit and a stable oscillator.
Descri~tion of the Preferred Embodiment As shown in Figure 1, the circuit diagram for the control board for the programmable light-activateci emergency marking system is relatively uncomPlicated due to the presence of integrated circuits 1 and 2. Fic7ure 2 shows the logic diagram for the 4093 integrateci circuit 1.
In Figure 1, the power suPPly 15 is rated at +3.0 volts DC7 and in the present device this is achieved through the use of Four commercially available "D" cell batteries. In order to assure correct voltage at all times, two batteries are connected in parallel, and two in series. The power supply may comprise non-rechargeable batteries, rechargeable batteries, or a rectified AC current. When batteries are employed, it will also be desirable to include indicator means to indicate when a battery is becom;ng depleted.
BeFore the system is installed by the end user, the . ~
~29~
shorting plug 14, is placed across one of the three ,junction~.
In this way, the current can only exit the 4020 inte~rated circuit 2 at only one of pins one 16, two 17, or three i8. IP
the plug 14 is placed to connect pin one 16, upon activation the unit flashes for half an hour, pin two 17 the unit FIashes for one hour, and p;n three 18 causes the unit to flash for two hours.
As well, khe lOOK ohm variable resistor 3 mwst be adjusted before installation. This is a single turn potentiometer and is used to set the phototransistor 5 gain.
Under operating conditions, the output of the phototransistor 5 feeds a schmidt trigger at Pin twelve 32 of the 4093 integrated c1rcuit 1, that conditions the input signal giving the light sensitivity required hysteresis.
Normally, when light levels are high, the input signal at pin twelve 32 is a logic 1, causing the output signal at pin eleven 31 to be a logic 0; however, when light levels drop below the minimum threshold level set by the potentiometer 3, a losic 0 is applied to pin twelve 32, causing a logic 1 output signal at pin eleven 31.
In either case, the output signal from pin eleven 31 is fed lnto a stable oscillator (pins four 24 through ten 30 of the 4093 lntegrated circuit 1, as well as the 1 meg ohm resistor 7 and a 0.33 uf~ capacitator 6).
The output of the oscillator, pin ten 30, is a logic 1 when the light levels initially fall below the threshold level.
~i~9~8~
This value enters thP fourteen stage ripple counter (the 4020 integrated circuit Z) at pin ten 35.
Once act;vated, the second stage of the rlpple counter pulses a logic one through pin nine 19, passes through a lK
resistor 13 and forward biases the 2N3904 transistor 1~. This then causes the light emitting diodes 8 to 11 to flash.
Once actiYated, the unit continues to function until a logic 1 is emitted to Pins one 21 and two 22 of the 4093 integrated circuit 2~ The time this occurs depends upon where the shorting plug 14 was placed: after the 4096 pulse For pin one 16, 8192 Pulse for pin two 17, and 16384 pulse for pin three 18. A logic 0 is then transmikted from pin three 23 to pin nine 29 of the 4093 integrated circuit, which results in disabling the oscillator. This shutdown situation continues until the system is reset when the phototransistor 5 is once again forward biased, causing a logic 1 to enter pin eleven 20 of the 4020 integrated circuit 2, after resetting the ripple counter.
At any time during its operation, the unit can be reset by having the phototransistor 5 forward biased (light above the threshold level.) This not onlY resets the ripple counter (4020 integrated clrcuit 2), by sending a logic 1 to Pin eleven 20, but also stops the operation of khe a stable oscillator.
The 11ght-activated emergency marking system may be provided on a printed circuit board in accordance with present day practice and mounted within an emergency exit sign or other ~,~,, . ~2 ~
type of sign, if desired, with the light emitting diodes also mounted on the board.
The illumination means employed with the invention maY
be any combination of light emitting diodes, incandescent bulbs, or low thermal inartia incandescent bulbs, or one of the above.
It will further be appreciated that the components employed in this programmable light-activated emergency markir,g system may be either solid state sem; conductors, discrete components, or a mixture of both.
The foregoing d-iscussion of the programmable light-activated emergency marking system is merelY illustrative of the principles of the present invention, and there ara many modifications, changes, and adaptations thereto which will be readily apparent to those skilled in the art without departure from the spirit and scope of the present invention and while it has been ch;efly descr;bed with reference to an emergency sign system, it is readily adaptable to other applications utilizing batteries which may be activated upon rsduction of surrounding l;ght levels.
,,,,;
Summarv of the Invention It is common for battery-Powered emergency marking systems to be activated by an interruption of AC power. Signs of this type ignore the possibility that although AC current is being suppl;ed, burnt out room light bulbs or brown out condit;ons (when line voltage is less than the rated level) can cause the area where the sign is placed to be in darkness, thereby rendering the unlit sign v1rtually invisible and vit1ating its whole intent and purpose. As well, these type of signs generally are associated with high operating expenses: for installation they must be hardwired to an AC current, and for operation electricity and malntenance (eg. incandescent bulb replacement) must be supplied.
. .. ~
~ ;. t ~
,, ~ , ,., ., . ~
1 2 ~
It is there~ore the primary object of the present invention to Provide an emergency markin~ sYstem wh1ch interactively responds to varlous surrounding light levels (ie.
light activated) so that the system becomes operational when it ls needad (;e. when light levels fall below a minimum threshold level.) Another ob~ject of the invention is to allow the length of time of operation, as well as the minimum threshold light level required for activation, to be programmable so that the system can give optimum performance in all situations.
Another object of the invention is to provide a highly visible sign with minimal d;stortion by generally distributing the light evenlY over the face of the sign.
A further object of the invention is to reduce the cost and provide an extremely long virtu~lly maintenance-free life for the system by minimizlng both the clrcuit complexity and the number of components in the system.
The above and other objects of the ~nvention are realized through the use of a li~ht sensor, control board, and light source.
The present device uses light em1tting diodes to provide a high visibility, low power source of illumination which has a long operating life. By connecting the light emitting diodes in parallel the voltage requirements are reduced to a minimum. In addition, the light emltting diodes cause a wide dispersion of the light so as to greatly reduce the light "highs ~ ,., ";.~
~ 8.~
and lows" on the face ef the sign as compared to those produced by incandescent bu 1 bs .
The present device uses a phot.otranslstor connecked to the control circuit as the light sensor. The phototransistor gain is controlled by a variable resistor, so that the threshold level oF light for activation can be changed in order to best suit the requirements of the system's eventual physical location.
When this minimum threshold level is reached, the system is activated and the light em;tting d;odes flash until either the system is reset or the pre-set time per-iod has elapsed.
In addition, the present device uses a fourteen stage ripple counter integrated circuit connected to the external circuitry via a shorting Plug in order to program the length of time for activation. In many situations, it is desirable ko have the sYstem cease operaking before the batteries are depleted.
Therefore, by placing the shorting plug in one of the three possible posit;ons supplied bY the present device, either one half-hour, one hour, or two hours of operation can be selected.
Th;s programmable abil;ty greatly increases the utility of the system, since the battery is not completely drained the first time the system is activated.
The above and other objects, features, and advantages of the present ;nvention will become more aPparent from the following detailed descr;pt;on, wherein I have shown and described only the preferred embodiment of the lnvention, simply by way of ;llustrakion of the best mode contemplated by me of . ~, . . ..
~?9~;385 carrying out mY invention. As will bs realized, the invention is capable oF differen~ embodiments, and capable of modlf1cation in various obvious respects, all without dePartin~ from the invention. Accordingly, the drawings and descripk;on are to be regarded as illustrative in nature, and not as restrictive.
Brief DescriDtion oF t e Drawin~s Figure 1 is a c;rcuit diagram of the control board for the programmable light-activated emergency marking system;
Figure 2 is a logic diagram of the 4093 Integrated circuit and a stable oscillator.
Descri~tion of the Preferred Embodiment As shown in Figure 1, the circuit diagram for the control board for the programmable light-activateci emergency marking system is relatively uncomPlicated due to the presence of integrated circuits 1 and 2. Fic7ure 2 shows the logic diagram for the 4093 integrateci circuit 1.
In Figure 1, the power suPPly 15 is rated at +3.0 volts DC7 and in the present device this is achieved through the use of Four commercially available "D" cell batteries. In order to assure correct voltage at all times, two batteries are connected in parallel, and two in series. The power supply may comprise non-rechargeable batteries, rechargeable batteries, or a rectified AC current. When batteries are employed, it will also be desirable to include indicator means to indicate when a battery is becom;ng depleted.
BeFore the system is installed by the end user, the . ~
~29~
shorting plug 14, is placed across one of the three ,junction~.
In this way, the current can only exit the 4020 inte~rated circuit 2 at only one of pins one 16, two 17, or three i8. IP
the plug 14 is placed to connect pin one 16, upon activation the unit flashes for half an hour, pin two 17 the unit FIashes for one hour, and p;n three 18 causes the unit to flash for two hours.
As well, khe lOOK ohm variable resistor 3 mwst be adjusted before installation. This is a single turn potentiometer and is used to set the phototransistor 5 gain.
Under operating conditions, the output of the phototransistor 5 feeds a schmidt trigger at Pin twelve 32 of the 4093 integrated c1rcuit 1, that conditions the input signal giving the light sensitivity required hysteresis.
Normally, when light levels are high, the input signal at pin twelve 32 is a logic 1, causing the output signal at pin eleven 31 to be a logic 0; however, when light levels drop below the minimum threshold level set by the potentiometer 3, a losic 0 is applied to pin twelve 32, causing a logic 1 output signal at pin eleven 31.
In either case, the output signal from pin eleven 31 is fed lnto a stable oscillator (pins four 24 through ten 30 of the 4093 lntegrated circuit 1, as well as the 1 meg ohm resistor 7 and a 0.33 uf~ capacitator 6).
The output of the oscillator, pin ten 30, is a logic 1 when the light levels initially fall below the threshold level.
~i~9~8~
This value enters thP fourteen stage ripple counter (the 4020 integrated circuit Z) at pin ten 35.
Once act;vated, the second stage of the rlpple counter pulses a logic one through pin nine 19, passes through a lK
resistor 13 and forward biases the 2N3904 transistor 1~. This then causes the light emitting diodes 8 to 11 to flash.
Once actiYated, the unit continues to function until a logic 1 is emitted to Pins one 21 and two 22 of the 4093 integrated circuit 2~ The time this occurs depends upon where the shorting plug 14 was placed: after the 4096 pulse For pin one 16, 8192 Pulse for pin two 17, and 16384 pulse for pin three 18. A logic 0 is then transmikted from pin three 23 to pin nine 29 of the 4093 integrated circuit, which results in disabling the oscillator. This shutdown situation continues until the system is reset when the phototransistor 5 is once again forward biased, causing a logic 1 to enter pin eleven 20 of the 4020 integrated circuit 2, after resetting the ripple counter.
At any time during its operation, the unit can be reset by having the phototransistor 5 forward biased (light above the threshold level.) This not onlY resets the ripple counter (4020 integrated clrcuit 2), by sending a logic 1 to Pin eleven 20, but also stops the operation of khe a stable oscillator.
The 11ght-activated emergency marking system may be provided on a printed circuit board in accordance with present day practice and mounted within an emergency exit sign or other ~,~,, . ~2 ~
type of sign, if desired, with the light emitting diodes also mounted on the board.
The illumination means employed with the invention maY
be any combination of light emitting diodes, incandescent bulbs, or low thermal inartia incandescent bulbs, or one of the above.
It will further be appreciated that the components employed in this programmable light-activated emergency markir,g system may be either solid state sem; conductors, discrete components, or a mixture of both.
The foregoing d-iscussion of the programmable light-activated emergency marking system is merelY illustrative of the principles of the present invention, and there ara many modifications, changes, and adaptations thereto which will be readily apparent to those skilled in the art without departure from the spirit and scope of the present invention and while it has been ch;efly descr;bed with reference to an emergency sign system, it is readily adaptable to other applications utilizing batteries which may be activated upon rsduction of surrounding l;ght levels.
,,,,;
Claims (9)
1. A programmable light-activated emergency marking system operative in response to the reduction of surrounding light levels, the improvement including:
(A) a power source;
(B) detection means to determine the level of surrounding light;
(C) illumination means to Provide a source of illumination;
(D) switch means to activate illumination and timing means upon input from detection means;
(E) means to permit activation of the illumination means for a predetermined period; and (F) restoring means to restore the timing means and illumination means of said system to the inactive state, said restoring means operative upon detection by detection means of light levels above the required minimum level.
(A) a power source;
(B) detection means to determine the level of surrounding light;
(C) illumination means to Provide a source of illumination;
(D) switch means to activate illumination and timing means upon input from detection means;
(E) means to permit activation of the illumination means for a predetermined period; and (F) restoring means to restore the timing means and illumination means of said system to the inactive state, said restoring means operative upon detection by detection means of light levels above the required minimum level.
2. A programmable light-activated emergency marking system in accordance with claim 1 further comprising means for adjusting the length of time the system is illuminated (timing means) once the said system has been activated.
3. A programmable light-activated emergency marking system as claimed in claim 2 further comprising means for adjusting the minimum threshold level of light required by the detection means to activate the switch means which in turn activate the illumination means.
4. A programmable light-activated emergency marking system as claimed in claim 3 wherein components A, B, C, D, E and F are solid state semi-conductors, discrete components, or a mixture of both.
5. A programmable light-activated emergency marking system as claimed in claims 1, 2, or 3 wherein the power source consists of either non-rechargeable batteries, rechargeable batteries, or a rectified AC current.
6. A programmable light-activated emergency marking system as claimed in claims 1, 2, or 3 wherein there is provided in said system a timing means to establish a rate and cause the illumination means to flash at said timing rate.
7. A programmable light-activated emergency marking system as claimed in claim 5 further comprising indicator means to indicate when a battery is sufficiently depleted.
8. A programmable light-activated emergency marking system as claimed in claim 1, wherein the said illumination means comprises light emitting diodes.
9. A programmable light-activated emergency marking system as claimed in claims 1, 2 or 8 wherein the illumination means are arranged in a perceivable form.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000601294A CA1290385C (en) | 1989-05-31 | 1989-05-31 | Programmable light activated emergency marking system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000601294A CA1290385C (en) | 1989-05-31 | 1989-05-31 | Programmable light activated emergency marking system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1290385C true CA1290385C (en) | 1991-10-08 |
Family
ID=4140134
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000601294A Expired - Lifetime CA1290385C (en) | 1989-05-31 | 1989-05-31 | Programmable light activated emergency marking system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1290385C (en) |
-
1989
- 1989-05-31 CA CA000601294A patent/CA1290385C/en not_active Expired - Lifetime
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |