Tumbling magnet generates extra power

Problem: . The batteries always seem to go flat when they are most needed, usually because the lights have been left switched on. A traditional bicycle dynamo may be pressed against the rear tyre, but apart from being a somewhat clumsy item, it incurs a significant amount of friction, and is not really suitable for use on racing bicycles with narrow tyres. The voltage output of the dynamo and brightness of the bicycle lights depends on speed, which become invisible if the bicycle is being pedalled very slowly. Solution: Mr Qin Gang, who lives in central London and rides a bicycle as his preferred mode of transport has invented and applied for patent on a non friction contact bicycle generator that is highly efficient and whose periodic voltage output is not dependent on speed. His breakthrough is to put a magnet inside a film can sized container, flipped over by passage of a second magnet mounted on the spokes of the wheel. Pulses of current are induced in a coil of wire wound round the outside of the container by the magnet inside it being flipped over. The magnet in the container produces a much more rapidly changing field when it flips than is produced by the relatively slow passage of the magnet on the wheel. Mr Gang says that when fitted it to his own bike, it was able to make more than 20 LEDs flash. Applications: Mr Gang offers his solution as a kit priced at £10 or £13 plus £2 p&p. For £10, a purchaser can expect a generator plus one white LED light for the front and two for the back. For the extra £3, movement of the rear break cable closes a switch to keep one of the rear LEDs lit for two to three minutes as a standby light. He suggests that the system could also be used to power flashing LEDs on wind powered advertising signs. Any moving piece of machinery could be fitted up to power warning flashing LEDs if required, or the power used to drive low powered electronics. TS Freelights Email to Freelights