US Patent 7152580 Engine speed control with high speed override mechanism

A secondary engine speed control mechanism for small internal combustion engines, including an operator control which is manually operable to override an engine running speed which is set by the engine's primary speed control mechanism and governed by the governor. The secondary speed control mechanism may be selectively actuated by the operator in anticipation of an increased engine load to provide a temporary increase or “boost” to engine speed above the set, governed engine running speed. The secondary speed control mechanism may be either mechanically or electrically actuated, and may include an operator actuated, trigger-type mechanism or an electrical switch located on the handle of an implement with which the engine is used.