Over-compressed engine
AssigneePinnacle Engines, Inc.
InventorsJames M. Cleeves, Nicholas Manov, Michael A. Willcox, Simon David Jackson
Life of this patent
Estimating the term…
Abstract
A system and method are disclosed for fabricating and running an engine in two modes. The first mode is an efficiency mode having a high compression ratio and efficiency for low to medium loads. The second mode is a power mode having high power density for higher loads. The system may use a lean mixture in the efficiency mode, which mixture is made richer for more power in the power mode. The system may also use ignition timing to allow the efficiency mode and the high power mode to be at the same mixture.
Claims19
A method comprising:
- running an internal combustion engine in an efficient mode to provide power for a first engine load on the internal combustion engine, the efficient mode comprising providing a first air/fuel mixture that is lean and a first ignition timing that is approximately at a maximum brake torque timing;
- and
- transitioning from the efficient mode to a power mode to provide power for a second engine load that is larger than the first engine load and also larger than a maximum load achievable can be provided in the efficient mode with the internal combustion engine operating under a wide open throttle (WOT) condition, the power mode comprising providing a second air/fuel ratio that is less lean than the first air/fuel mixture and a second ignition timing that is retarded relative to the maximum brake torque timing.
A method of fabricating an internal combustion engine, comprising the steps of:
- (a) configuring the engine to run in an efficient mode where compression ratio of the engine is determined by one or more of the following steps during the efficient mode:
- i. setting the air/fuel mixture to be a lean mixture at wide open throttle;
- ii. inducting the air/fuel mixture into the combustion chamber in a turbulence inducing manner;
- iii. maintaining a temperature of all walls defining the combustion chamber to a temperature not exceeding a temperature of a piston crown of a piston reciprocating within the engine;
- iv. acceptable levels of knock;
- and
- v. drive cycle performance;
- and
- (b) configuring the engine to run in a power mode in which more power is delivered than in the efficient mode with the engine operating at wide open throttle, a transition from the efficient mode to the power mode being accomplished by changing the air/fuel ratio to a more rich mixture than the lean mixture and retarding timing of a combustion ignition spark.
An internal combustion engine, comprising:
- a combustion chamber at least partially defined by wall of a cylinder and having one or more internal surfaces;
- at least one piston moving within the cylinder;
- and
- one or more control devices that cause the internal combustion engine to run in an efficient mode to provide power for a first engine load on the internal combustion engine, the efficient mode comprising providing a first air/fuel mixture that is lean and a first ignition timing that is approximately at a maximum brake torque timing, the one or more control devices causing the internal combustion engine to transition from the efficient mode to a power mode to provide power for a second engine load that is larger than the first engine load and and also larger than a maximum load achievable can be provided in the efficient mode with the internal combustion engine operating under a wide open throttle (WOT) condition, the power mode comprising providing a second air/fuel ratio that is less lean than the first air/fuel mixture and a second ignition timing that is retarded relative to the maximum brake torque timing.
Dependencies are inferred from the claim text.