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Eccentric spur gear, module 1, 40 T, Ø5 bore 5 mm off centre, Ø3 centre stud hole

What is an eccentric gear? · Modern device · basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance

Also called: eccentric gear, off centre gear, eccentric spur gear, engranaje excéntrico, Exzenterzahnrad

Exact dimensions. True size, with no printing tolerance added.

length
41.99 mm
width
41.99 mm
height
8.0 mm

Notes

  • Ordinary module 1, 40-tooth involute gear (pitch Ø40, face 8) whose Ø5 shaft bore is 5 mm off its geometric centre, with a Ø3 hole at the true centre for the stud that keeps the link to the pinion. On its shaft it turns at constant speed while its pitch circle wobbles ±5 mm.
  • Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

Eccentric spur gear, module 1, 40 T, Ø5 bore 5 mm off centre, Ø3… size chart

dimensionvalue
module1
teeth40
boreØ5 at 5 mm from centre
centre holeØ3
face8 mm

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Henry T. Brown (1868, public domain)Five Hundred and Seven Mechanical Movements — scan on archive.orgwebPublisher's page; dimensions are facts
507movements.comBrown's movement No. 222: figure, his text and an animationwebPublisher's page; dimensions are facts
Xem StudiodrawingwebPublisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

eccentric-spur-gear-m1-40t-e5gear centred on the origin, bore at (−5, 0), a tooth on +X, z 0..8STEP · STL
Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.
Set it up →

Plain text: sheet.txt · JSON: /api/geometry?object=eccentric-spur-gear-m1-40t-e5-b5

Eccentric spur gear, module 1, 40 T, Ø5 bore 5 mm off centre, Ø3 centre stud hole, isometric render of a generated part
Render of eccentric-spur-gear-m1-40t-e5 from the free STEP; not to scale.

Fits with

Eccentric spur gear and pinion on a swinging arm (variable speed), isometric render of a generated part
Eccentric spur gear and pinion on a swinging arm (variable speed)4 sizes★ 1 file

Questions

What is an eccentric gear?

Ordinary module 1, 40-tooth involute gear (pitch Ø40, face 8) whose Ø5 shaft bore is 5 mm off its geometric centre, with a Ø3 hole at the true centre for the stud that keeps the link to the pinion. On its shaft it turns at constant speed while its pitch circle wobbles ±5 mm.