US Patent 10954875 Control of combustion engine shut down

The abrupt cessation or run-away of a combustion engine may damage the combustion engine and pose a safety hazard to the surrounding environment. The combustion engine operational mode may be controlled, regulated or maintained by regulating the combustion mixture of the combustion engine. The oxidizer flow, a material or both of the combustion mixture may be regulate to create or form a combustion material that is outside a combustible range such that the combustion engine is placed or maintained in a spin-down operational mode. The material added to the combustion mixture may include a combustible, non-combustible, oxidizer, or exhaust material. A brake may also provide a secondary mechanism to maintain or place the combustion engine in a spin-down mode.