smoke detector with cheap pathway light photovoltaic = cease to fail.
Although hundreds of millions of smoke detectors are keeping people from harm right now it occured to me that when they go nonfunctional it mostly from user annoyance. The battery replacement beeps perhaps prompt people to simply remove the battery then they neglect to replace the battery.
Combining hypercheap pathlight photovoltaics with a cheap smoke detector keeps the battery functioning much longer. It also creates an opportunity to keep people from harm if the battery ceases working, the photovoltaic restores sufficient electricity to keep the smoke detector working during 7pm to 7am or longer when people are most likely to be at the building.
Also the smoke detector could simply say once a week or month "time to replace the battery I am only active from 7 to 7 right now" it is mild thus the battery is less likely to be removed. The electronics of talking magazine advertisements are cheap enough to do this. (10 cents or less)
The inside of a smoke detector could be a reflective shape that directs much more light at the photovoltaic even through a screened appearance, kind of like the moonlighter.
I searched online as well as at patents. There are no photovoltaic rechargeable smoke detectors described previously. This is like an instantly assembleable project as well. Its public domain like all my things.-- beanangel, Jun 10 2011 smoke alarm numbers http://www.nfpa.org.../OS.SmokeAlarms.pdfAlmost two-thirds of home fire deaths resulted from fires in properties without sounding [beanangel, Jun 10 2011, last modified Jun 23 2011] light concentrator moonlighterThe moonlighter gathers surrounding light to an area so people could read The nside of a smoke detector could be reflective shape that directs much more light at the photovoltaic even through a screened appearance [beanangel, Jun 10 2011] (?) 20 cent talking ic with speaker plus PCB http://www.alibaba....ng_IC_for_toys.htmlIf you just use the ic thats less than 20 cents to bring voice reminder to smoke alarms Digikey has similar items at 20c or less [beanangel, Jun 10 2011] 10c talking ic with PCB http://www.alibaba....IC_10Sec_15Sec.html [beanangel, Jun 10 2011] The main concern is the amount of light you're going to get if it's mounted on the ceiling.
If you were really nifty you could have it powered by the heat of the fire it's warning you against - maybe a Stirling engine attached to a centrifugal bell?-- mitxela, Jun 10 2011 (+)
[mitxela], now THERE'S an idea I could vote for. Please post that one.-- normzone, Jun 10 2011 Actually looking at the numbers With all the nonfunctional smoke detectors made functional thats just 640 people per year as well as less than a billion $ of material rescued at the US. Worldwide though the technology could save a few thousand lives a year. The Chinese might benefit strongly. Itd be a nifty export to China-- beanangel, Jun 10 2011 Now this is good idea.-- MaxwellBuchanan, Jun 10 2011 Why not use the Americium source in a smoke detector to power a tiny-tiny radioisotope phosphorescent photovoltaic generator to tricke charge the battery?-- DIYMatt, Jun 11 2011 The reason I suggest exporting this to China is that its possible to make a much better much cheaper smoke detector as a system on a chip.
There are photodiode smoke detectors, thus if there is a photovoltaic chip process that also permits photodetector creation as well as logic the entire smoke detector could be just one IC produceable at less than .20c each. Then people throughout the developing world could have them, possibly saving tens of thousands of lives a year.
It is possible this is a very simple use of the earliest photovoltaic with logic (or logic with just one photodector on silicon) at the same ic technology available provinding a stimulus to those technologies.-- beanangel, Jun 13 2011 Some people actually quite like watching houses burn down ...-- 8th of 7, Jun 13 2011 why not make a sterling engine or thermovoltaic powered smoke detector. That way when it gets hot like from the raging fire, it will go off. I think people are not realizing the untapped energy represented by a house fire.-- metarinka, Jun 15 2011 That wouldn't be a smoke detector, it would be a fire detector.-- DIYMatt, Jun 15 2011 There's no smoke without fire.-- pocmloc, Jun 15 2011 random, halfbakery