US 12,454,925 B2
Systems and methods of using a fuel injector as a pressure sensor to detect top-dead-center for a cylinder
Shailesh Nair, Pune (IN); Mayur H. Borate, Maharashtra (IN); Srinivas Kumar Mulukutla, Pune (IN); Panendra Kumar Sahu, Pimpri Chinchwad (IN); and David Michael Carey, Bend, OR (US)
Assigned to Cummins Inc., Columbus, IN (US)
Filed by Cummins Inc., Columbus, IN (US)
Filed on Oct. 26, 2023, as Appl. No. 18/495,690.
Application 18/495,690 is a continuation of application No. PCT/US2022/027497, filed on May 3, 2022.
Prior Publication US 2025/0137417 A1, May 1, 2025
Int. Cl. F02D 41/38 (2006.01); F02D 1/06 (2006.01)
CPC F02D 41/3845 (2013.01) [F02D 1/06 (2013.01); F02D 2041/389 (2013.01); F02D 2200/024 (2013.01); F02D 2200/0602 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A system for determining a top-dead-center (“TDC”) position of a piston configured to reciprocate in an engine cylinder, comprising:
a fuel injector fluidically coupled to a fuel accumulator and configured to inject fuel from the fuel accumulator into the engine cylinder;
a pressure sensor positioned to sense pressure of fuel in the fuel accumulator; and
a controller in communication with the fuel injector and the pressure sensor, the controller being programmed to receive signals from the pressure sensor indicating the sensed pressure of fuel in the fuel accumulator,
prevent fuel flow into the fuel accumulator when the sensed pressure of fuel corresponds to a desired fuel pressure,
after fuel flow into the fuel accumulator is prevented, cause the fuel injector to provide a plurality of fuel injections into the engine cylinder when the piston is in a corresponding plurality of positions in the engine cylinder,
estimate a corresponding plurality of cylinder pressures in response to the plurality of fuel injections,
fit a curve to the corresponding plurality of cylinder pressures that have been estimated,
determine a maximum cylinder pressure value on the curve, and
correlate the maximum cylinder pressure value to a true TDC position of the piston.