US Patent No. 9,790,867


Patent No. 9,790,867
Issue Date October 17, 2017
Title Deceleration Cylinder Cut-off
Inventorship Steven E. Carlson, Oakland, CA (US)
Xin Yuan, Palo Alto, CA (US)
Siamak Hashemi, Farmington Hills, MI (US)
Vijay Srinivasan, Farmington Hills, MI (US)
Srihari Kalluri, Ann Arbot, MI (US)
Andrew W. Phillips, Rochester, MI (US)
Mark A. Wilcutts, Berkeley, CA (US)
Louis J. Serrano, Los Gatos, CA (US)
Shikui Kevin Chen, San Jose, CA (US)
Assignee Tula Technology, Inc., San Jose, CA (US)

Claim of US Patent No. 9,790,867

1. A method of operating an engine having a crankshaft, an intake manifold and a plurality of working chambers, the method
comprising, during operation of the engine:
deactivating all of the working chambers in response to a no engine torque request such that none of the working chambers
are fired and no air is pumped through the working chambers as the crankshaft rotates;

subsequent to the deactivation of all of the working chambers, reactivating at least some of the working chambers to pump
air through the reactivated cylinders during a series of air pumping working cycles to thereby reduce the pressure in the
intake manifold, wherein the reactivated cylinders are not fired during the air pumping working cycles; and

firing at least some working cycles only after at least a plurality of the air pumping working cycles have been executed to
cause the engine to deliver the requested torque, whereby the intake manifold pressure at the time that the first fired working
cycle after the deactivation of all of the working chambers begins, is lower than the intake manifold pressure immediately
before the first of the series of air pumping working cycles.