Generator

thingiverse

Single Phase 6 Pole Generator: One major issue with three-dimensionally printed generators is magnetic permeability. I employed six M3x16 bolts to concentrate and make better use of the magnetic flux. One of the benefits of using these bolts, which are arranged radially, is being able to thread them in or out to adjust the air gap. Non Printed Components: - Two flanged ball bearings with 1/2" inner diameter and 1/4" outer diameter - One 1/4" diameter D-shaft (a 1/4" threaded rod can be used) - Two 1/4" inner diameter shaft spacers - 28 AWG wire - Heat shrink - Twelve 10mm x 2mm diameter magnets Print: - One stator - One lid - Twelve coil forms - One rotor Assembly: Rotor: Two magnets fit in each hole, stacked on top of each other. Each pole/hole must alternate N/S/N/S/N/S all the way around the rotor. Press them into place, not too hard or the rotor may crack (depending on the tolerance of your printer). I use glue as well to hold all of the magnets in place. Then I wrap a thin layer of tape around the outside as an extra measure. Insert the D-shaft through the rotor (if it's tight, a hammer helps!). Stator: For each of the radial bolts thread one of the coil forms all the way to the top. Then I thread one more and keep it close to the bottom. Then I screw the bolts into the stator casing as shown in the picture. Once the bolts are placed radially around the stator, I begin to wind. I did 200 windings around each bolt. Using one continuous wire wrap clockwise around the bolt 200 times, move to the next adjacent bolt and wrap 200 turns clockwise, continue until all bolts are covered. Cover the windings with heat shrink or tape to protect them. Final Assembly: Insert one of the bearings into the stator casing, with the flange on the inside of the case, place a spacer (or washer if you don't have a spacer) on the shaft that has the rotor on it and place the shaft through the stator case bearing. The rotor should kind of snap into place as it's attracted to the bolts. Now place a spacer on the lid and of the shaft, and the bearing with the flange facing inward. Place the lid on the bearing and use three more M3x16 bolts to bolt the lid on the casing with the smaller raised diameter facing outward. Otherwise, it will bind. Finally, spin it and produce electricity! It will feel like a stepped motion because the permeable material is only every 45 degrees (and the lid retaining bolts). While spinning the last version at approximately 4000RPM, it output 35ma @ 5.2v, which is about 1.8W (through a rectifier and underload). I can't remember if I used more windings on that one, but spinning this one by hand, I got a maximum of 10.2Vpp and 3Vrms or so. It's not a lot of power, but enough to drive a few LEDs or something else for a micro-wind/hydro installation or an IoT installation. There are many things that can be improved and using materials with different properties allows for higher output three-dimensionally printed generators. This fits in the palm of my hand, and the principles can be scaled up. We can use readily available materials alongside 3D printing to do great things!