Crank with closed channel yoke (uniform-speed reciprocation) — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/uniform-motion-crank-yoke-mechanism/ (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/) Basis: Xem Studio design following Brown No. 354 (1868) Catalog version: 2026-10-20 Sizes: see table below - A plain crank pin runs in a closed channel cut in the crosshead instead of a straight slot. The channel's shape is the pin's path relative to a crosshead moving at constant speed, so the crosshead travels 24 mm out at uniform speed during half a turn and back during the other half — a crank made to behave like a heart cam. - Drawn at θ = 50°: crosshead at x = -5.33 mm, the Ø3 pin touching both walls of the 3 mm channel. Direction reverses sharply at the channel's two points (θ = 0° and 180°), the price of uniform speed. - Brown's No. 354 (crank and slotted cross-head modified for uniform velocity, from No. 93). - Parts (each has its own page): crank-disc-36-pin-r12, uniform-motion-yoke-plate-60x40-r12, linear-shafts-h6, dowel-pins-metric. - Brown's movement No. 354 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size. parameter value crank radius 12 mm stroke 24 mm, uniform speed channel 3 mm, closed loop speed 48 mm per crank turn Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Henry T. Brown (1868, public domain): Five Hundred and Seven Mechanical Movements — scan on archive.org — web — Publisher's page; dimensions are facts — https://archive.org/details/fivehundredseven00browiala - 507movements.com: Brown's movement No. 354: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_354.html Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/uniform-motion-crank-yoke-mechanism/index.json API: https://xemstudio.com/api/geometry?object=uniform-motion-crank-yoke-mechanism