tweeplankregelaar

The tweeplankregelaar, also known as a two-plank regulator or two-plank governor, is a mechanical device used to control the speed of steam engines by regulating the supply of steam to the engine cylinders. It was developed in the early 19th century as an improvement over earlier governor designs, such as those by James Watt.

The tweeplankregelaar consists of two parallel, rotating arms (or "planks") connected by a central spindle. These arms are mounted on a vertical shaft that rotates with the engine’s speed. Attached to the outer ends of the arms are spherical weights, which move outward as the engine’s speed increases due to centrifugal force. The inner ends of the arms are connected to a linkage system that controls the steam valve, adjusting the steam flow to maintain a consistent speed.

The design relies on the balance between centrifugal force and gravity. When the engine speeds up, the weights move outward, lifting the inner ends of the arms and reducing steam flow, thereby slowing the engine. Conversely, if the engine slows down, the weights drop, increasing steam supply and restoring speed. This feedback mechanism helps stabilize the engine’s operation.

The tweeplankregelaar was widely used in early steam locomotives and stationary engines due to its simplicity and effectiveness. While later designs, such as the Porter governor, incorporated additional refinements, the tweeplankregelaar remains a foundational example of governor technology in steam engine control systems. Its principles influenced later developments in speed regulation for both mechanical and industrial applications.