The lengths of the links comply with the conditions: A͞C=A͞₁C₁, C͞D=C͞₁D₁ and C͞B=C͞₁B₁. Weights 7 are of equal weight. The governor is driven by a pair of bevel gears, 1 and 2. Mounted freely on sleeve 6 are two more bevel gears, 3 and 3', which have pins a. When the speed of the governor is increased, weights 7 raise sleeve 6 so that pin b, secured to sleeve 6, engages pin a of upper bevel gear 3 which meshes with bevel gear 4, thereby turning shaft 5 to reduce the admission of water (or steam). If the speed is reduced, the sleeve descends, pin b engages pin a of lower bevel gear 3' and shaft 5 is turned in the opposite direction to increase the admission of water (or steam).
$1634$SC,G$