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Triangular eccentric: curved (Reuleaux) triangle of width 30, pivoted at a corner

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

Also called: reuleaux triangle cam, triangular eccentric, constant width cam, excéntrica triangular, Dreieckexzenter

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

length
30.0 mm
width
37.0 mm
height
18.0 mm

Notes

  • Curved triangle of constant width 30 mm (three arcs of radius 30 about the opposite corners), 8 thick, with a Ø14 boss and a Ø6 blind bore at one corner: turned about that corner inside a yoke 30 mm wide, it moves the yoke with dwells at both ends.
  • Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

Triangular eccentric: curved (Reuleaux) triangle of width 30… size chart

dimensionvalue
width30 mm (constant)
pivota corner, Ø14 boss, Ø6 blind bore
thickness8 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. 91: 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

triangular-eccentric-reuleaux-w30as drawn in the mechanism's own frameSTEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=triangular-eccentric-reuleaux-w30

Triangular eccentric: curved (Reuleaux) triangle of width 30, pivoted at a corner, isometric render of a generated part
Render of triangular-eccentric-reuleaux-w30 from the free STEP; not to scale.

Fits with

Triangular eccentric: curved triangle turning in a yoke (motion with dwells), isometric render of a generated part
Triangular eccentric: curved triangle turning in a yoke (motion with dwells)4 sizes★ 1 file

Questions

What is a triangular eccentric?

Curved triangle of constant width 30 mm (three arcs of radius 30 about the opposite corners), 8 thick, with a Ø14 boss and a Ø6 blind bore at one corner: turned about that corner inside a yoke 30 mm wide, it moves the yoke with dwells at both ends.