US 12,467,399 B2
Variable exhaust control system
H. Sean Hilbert, Hillsdale, MI (US); Phil McDowell, Hillsdale, MI (US); and Scott Castonguay, Hillsdale, MI (US)
Appl. No. 15/752,366
Filed by Cobra Aero LLC, Cleveland, OH (US)
PCT Filed May 2, 2016, PCT No. PCT/US2016/030477
§ 371(c)(1), (2) Date Feb. 13, 2018,
PCT Pub. No. WO2016/179119, PCT Pub. Date Nov. 10, 2016.
Claims priority of provisional application 62/155,828, filed on May 1, 2015.
Prior Publication US 2019/0186329 A1, Jun. 20, 2019
Int. Cl. F01N 13/08 (2010.01); F01N 13/10 (2010.01); F02B 61/04 (2006.01); F02B 75/02 (2006.01); F02D 13/02 (2006.01); F02N 19/00 (2010.01)
CPC F01N 13/087 (2013.01) [F01N 13/10 (2013.01); F02B 61/04 (2013.01); F02B 75/02 (2013.01); F02D 13/0276 (2013.01); F02D 13/0284 (2013.01); F02N 19/004 (2013.01); F02B 2075/025 (2013.01); F02D 2013/0292 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An apparatus for adjusting power and noise characteristics of an internal combustion engine, comprising:
a wall configured to define an engine cylinder that includes a bore and further configured to define a compression relief passage that extends from a combustion chamber of the engine cylinder to an exhaust passage that is in fluid communication with the cylinder;
a compression relief valve configured to selectively adjust fluid flow capacity of the compression relief passage;
a piston configured to travel in the cylinder bore and further configured to compress a mixture that includes a fuel and oxygen;
an ignition source configured to initiate combustion of the mixture; and
a manifold configured to be in fluid communication with the exhaust passage, including
an exhaust bypass valve configured to permit an exhaust product resulting from ignition of the mixture to at least partially bypass a noise suppressor,
a noise suppression passage configured to accept the exhaust product from the exhaust passage and route at least part of the exhaust product to a noise suppressor when the exhaust bypass valve is at least partially closed; and
an exhaust vent configured to permit at least part of the exhaust product to bypass the noise suppressor when the exhaust bypass valve is at least partially open;
wherein operational characteristics of the engine can be adjusted along a range that extends from a first set of operational characteristics present when both the compression relief valve and the exhaust bypass valve are in a fully open position to a second set of operational characteristics present when both the compression relief valve and the exhaust bypass valve are in a fully closed position.
 
7. A method for operating a combustion engine, comprising:
actuating a compression relief valve to at least partially open a compression relief passage of an engine cylinder and permitting fluid in at least a portion of the engine cylinder to exit the engine cylinder through the compression relief passage; and
actuating an exhaust bypass valve to at least partially open an exhaust bypass passage and permit an exhaust product to exiting the engine and bypass a noise suppressor;
wherein a change in a position of at least one of the compression relief valve and the exhaust bypass valve changes at least one operational characteristic in a set of operational characteristics of the along a range that extends from a first set of operational characteristics that are present when both the compression relief valve and the exhaust bypass valve are in a fully open position to a second set of operational characteristics that are present when both the compression relief valve and the exhaust bypass valve are in a fully closed position.