Cummins Inc.
USING SKIP FIRE WITH POWER TAKE-OFF

Abstract:

Engine controllers and control schemes that facilitate skip fire engine operation in conjunction with use power take-off devices are described. In one aspect, a skip fire mode is exited when the power take-off unit is engaged and the current torque request exceeds a torque threshold. In some embodiments, the exit is delayed when the temperature of an after treatment system is below a designated temperature threshold. In another aspect, the engine transitions to the skip fire mode when the power take-off unit disengages. In some embodiments, exiting is conditioned on the current torque request being less than a torque threshold. In some embodiments, the transition is made immediately, whereas in others the transition only occurs when the power take-off unit is not reengaged for a period of time or is further conditioned on determining that the power take-off unit is likely to remain disengaged for the period of time.