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Round-belt generator drive: Ø84 crank pulley, 2208 generator pulley, Ø5 belts
How do I belt a small generator off a Stirling engine's crank? · Hardware · basis: Design values; 2208 rotor-top hole pattern from the gimbal-motor envelope on this site
Long Earth Society build part. The generator drive of my desk-style engines. The engines
Exact dimensions. Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part. Mating features
- sizes
- 4 in table
Notes
- A Ø5 round belt from an Ø84 crank pulley (pitch Ø80) to an Ø16 pulley (pitch Ø13.33) bolted to a 2208 gimbal motor's rotor top: 6 : 1, so 600 rpm at the crank is 3600 rpm at the generator.
- Belt lengths on the centre line: 339.1 mm at 90 centres (horizontal gamma), 415.2 mm at 130 (walking-beam gamma). Round belts are cut to length and joined; tension by stretch.
- The belt and pulleys turn the crank's shaft power into motor speed; the electrical output on each engine's page comes from the motor's published KV and resistance.
Sizes
| part | size |
|---|---|
| crank-pulley-84-b8 | Ø84 × 6, pitch Ø80, hub Ø20 |
| generator-pulley-2208-pd13.33 | Ø16 × 8, pitch Ø13.33 |
| round-belt-5-c90 | Ø5 × 339.1 |
| round-belt-5-c130 | Ø5 × 415.2 |
Mating features
Drawn at the exact size. Open press, slide, run and socket features by your process's clearance; leave designed gaps and clamp fits as drawn.
| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| crank pulley bore | Ø8 | Ø8 crank shaft (M4 grub) | slide | crank-pulley* |
| grooves | Ø5 round, pitch Ø80 / Ø13.33 | Ø5 round belt | designed | all |
| pulley flange holes | 4 × Ø2.4 on 12 × 12 | M2 screws into the 2208 rotor top | designed | generator-pulley* |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Long Earth Society | Engine builds | web, video | LES site |
Free files
★ Free files 4 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
| crank-pulley-84-b8 | crank pulley Ø84 × 6 with a Ø5 round-belt groove on pitch Ø80, hub Ø20 × 19.5, Ø8 bore, M4 tapped hub hole | STEP · STL |
| generator-pulley-2208-pd13.33 | generator pulley for a 2208 rotor top: flange Ø24 × 3 with 4 × Ø2.4 (12 × 12), neck Ø8, pulley Ø16 × 8 with a Ø5 groove on pitch Ø13.33 | STEP · STL |
| round-belt-5-c90 | Ø5 round belt on pitch circles Ø80 and Ø13.33 at 90 centres: 339.1 mm long on its centre line | STEP · STL |
| round-belt-5-c130 | Ø5 round belt on pitch circles Ø80 and Ø13.33 at 130 centres: 415.2 mm long on its centre line | STEP · STL |
Plain text: sheet.txt · JSON: /api/geometry?object=round-belt-generator-drive
How it fits
In these build lists
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Questions
What ratio?
6 : 1: the 2208's KV 128 then gives about 28 V open circuit at 600 rpm at the crank.