Deceleration cylinder cut-off

US9790867B2 · kind B2 · utility

Assignee

• Tula eTechnology, Inc. · US

Inventors

• Steven E. Carlson · Oakland, US
• Xin Yuan · Palo Alto, US
• Siamak Hashemi · Farmington Hills, US
• Vijay Srinivasan · Durham, US
• Srihari Kalluri · Ann Arbor, US
• Andrew W. Phillips · Saline, US
• Mark A. Wilcutts · Berkeley, US
• Louis J. Serrano · Los Gatos, US
• Shikui Kevin Chen · San Jose, US

Key dates

• Filing date: Jan 28, 2016
• Grant date: Oct 17, 2017
• Expiry date: Apr 20, 2036

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2250/41
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

Methods and arrangements for transitioning an engine between a deceleration cylinder cutoff (DCCO) state and an operational state are described. In one aspect, transitions from DCCO begin with reactivating cylinders to pump air to reduce the pressure in the intake manifold prior to firing any cylinders. In another aspect, transitions from DCCO, involve the use of an air pumping skip fire operational mode. After the manifold pressure has been reduced, the engine may transition to either a cylinder deactivation skip fire operational mode or other appropriate operational mode. In yet another aspect a method of transitioning into DCCO using a skip fire approach is described. In this aspect, the fraction of the working cycles that are fired is gradually reduced to a threshold firing fraction. All of the working chambers are then deactivated after reaching the threshold firing fraction.