Toggle (knee-lever) press mechanism — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/toggle-press-mechanism/  (CC BY 4.0)
Basis: Xem Studio drawing; classic mechanism (Brown No. 164)
Catalog version: 2026-10-20

Sizes: see table below
- Two equal links in line with the output, bent slightly at the knee. A side force F at the knee gives an end force F / (2·tan θ), θ = each link's angle off the straight line.
- At θ = 15° the gain is 1.87×; it rises without limit as the links straighten (θ → 0), which is why presses, clamps and stone crushers use it.
- The stroke shrinks as the force grows: the end moves 2L(1 − cos θ) while straightening.
- Parts (each has its own page): toggle-links-50, crosshead-8mm, crosshead-guide-8mm, pins-3mm. Brown's movement No. 164 shows it (1868).

parameter  value
link centres L  50 mm
angle θ (drawn)  15°
force gain at θ  1.87×

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

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/toggle-press-mechanism/index.json
API: https://xemstudio.com/api/geometry?object=toggle-press-mechanism