The perfect glove box item
Over the years I’ve built and written about plenty of hand-cranked LED torches. The articles have appeared in Silicon Chip magazine (see Our Fantastic Human-Powered LED Torches for an example) and in addition to those covered in the articles, I’ve built plenty of other torches for personal use. But now commercial hand-cranked LED torches have become available – and some of them are very good.
The one shown here was bought from Kmart here in Australia for AUD$24.95. It’s made in China and is imported by Nelson Industries.
Unlike most of the hand-cranked torches that I’ve built, this one doesn’t use a direct-drive stepper motor but instead uses a two-wire alternator. The rotational speed is stepped-up by an internal gearbox and this must be quite a high ratio as the long handle has a reasonable resistance to being turned. The benefit of using a gearbox is that the output from the alternator can be quite high for only a slow handle speed. However, the downsides are that the gearbox will wear out over time (the direct-drive stepper motor based torches will last pretty well for ever) and when winding the torch, it’s much noisier.
In addition to the generator, inside the case you’ll find a small printed circuit board, an 80mAH 3.6V nickel-metal hydride battery and three white LEDs. Well, they’re supposed to be white but they’re a very blue white! However, the three LEDs are well optimised optically, with individual lenses focusing the three outputs onto the one spot. At about 2 metres to the illuminated object the torch forms one circle of light; closer or further away than that and the three sources begin to re-appear.
Light output is very good. It’s not up to the latest Luxeon LEDs – but then again, use of those LEDs would make the torch far more expensive. The night range of the torch is very similar to a normal small torch, with a useable distance of about 7 or 8 metres. The torch fits comfortably in the hand and the winding handle is easy to use and yet when not needed, folds compactly into the torch body.
And of course the huge advantage of this design is that you’ll never have a flat battery. While it states on the packaging that winding the handle for 1 minute will result in 45 minutes of light, the simple internal circuit suggest that by the time 45 minutes is up, the LEDs may still be providing light – but not much of it! But the real benefit is not having the torch on for hours at a time but the guarantee that you will have light when you need it. And that brings us to car use.
For my money (and the torch you see here was bought at normal retail) this is the perfect glove box companion. What’s that? Don’t need a torch? What if your car gets a flat tyre at night? Most boot lights aren’t bright enough to allow you to easily fish out the spare wheel, not to mention the wheel brace, jack, chocks… Mobile phone slides under a seat and you’re trying to locate it? Have a domestic blackout and wonder where the hell all the torches are? Useful situations are many.
And, in addition to being assured that you’ll never have a flat battery, LEDs are far more rugged than incandescent filament lamp bulbs – so when you drop the torch on the hard ground during that struggle with the spare wheel, you’ll still be laughing. Well, maybe not laughing… but you get the picture.
Product detail: Nelson Dynamo LED Torch, N280406088, Kmart, AUD$24.95 Footnote: At the time of writing, the torch was available on eBay from Hong Kong at AUD$5.49. |