Wedding ring glows by hand



    The American engineer Ben Kokes (Ben Kokes), intending to offer a hand and a heart to his girlfriend, made a wedding ring with a resonant transformer and three small LEDs among the gemstones. The idea is that the bride’s ring starts to glow when the groom takes her hand.

    The whole process is documented in the author’s blog. First of all, the project is created in the AutoCAD program for 3D modeling: you need to calculate so that after adding the parts, the ring comes out with the correct inner diameter, the sizes of the stones and the recesses under them, as well as the distance between the recesses.



    The ring of the desired diameter is machined from a titanium blank.



    Recesses for gems are made with a drill.



    The workpiece is cut and polished.



    Then the stones gently stick.



    To make the backlight, the author implemented a resonant transformer , which wirelessly transfers energy between two windings, each of which is included in the oscillating circuit at close resonant frequencies. Ben Cokes introduced a copper winding with a capacitor into the ring, three LEDs are connected in parallel to the circuit. With an 820 pF capacitor, the resonant frequency was 1.5 MHz.



    The groom must carry the transmitter winding with the power source on his hand. The transmitter design is borrowed here . The device came out quite massive, but it can still be hidden unnoticed in the sleeve.









    The effect is shown in the video.



    Cows’s blog has step-by-step instructions on how to carve such a ring of a given diameter, make indentations under stones, etc.

    All the work took the author five months: from January to May 2013. Several options for fastening stones and ring thickness have been tested. Many test versions of the ring had to be thrown out.



    Finished result close-up.



    PS The author wanted to surprise the girl with a luminous ring, and the next day, go with her to the jewelry store and buy something solid. To his surprise, the girl refused to change the decoration, but only asked to slightly increase the inner diameter. The finger was 15.72 mm, not 15.6 mm, as Ben suggested, so the ring came out a little cramped.

    Also popular now: