Patent ID: 9121358
Filing Date: 2015-09-01
Classification: F01L,F02D,F02N,Y02T

Abstract:
1. A method of using a variable cam timing phaser in an internal combustion engine with a stop-start mode of operation, in which the phaser comprises: a housing assembly with an outer circumference for accepting drive force and a rotor assembly for connection to a camshaft, coaxially located within the housing having a plurality of vanes, wherein the housing assembly and the rotor assembly define at least one chamber separated by a vane into an advance chamber and a retard chamber, the vane within the chamber acting to shift relative angular position of the housing assembly and the rotor assembly; a control valve for directing fluid to and from the chambers through an advance line, a retard line, a common line, an advance detent line and a retard detent line, the control valve being movable in a first bore towards an advance mode, a holding position, a retard mode, and a detent mode, a lock pin slidably located in the rotor assembly or the housing assembly, the lock pin being moveable in the second bore from a locked position in which an end portion engages the recess, locking the relative angular position of the housing assembly and the rotor assembly, to an unlocked position, in which the end portion does not engage the recess; a piloted valve in the rotor assembly, movable from a first position to a second position; the method comprising the steps of, when the engine is in a stop mode of the stop-start mode: adjusting a duty cycle of an actuator coupled to the control valve of the phaser to command the control valve to the retard mode; maintaining the duty cycle of the actuator to command the control valve to remain in the retard mode until an automatic restart of the engine; detecting if the key is in an off position, and if the key is in an off position, performing the steps of: