Patent ID: 7077083
Filing Date: 2006-07-18
Classification: F01L,F02B,Y02T

Abstract:
1. A module for providing selective lost motion in a hydraulically-actuated valve train of an internal combustion engine having a lost-motion bore in hydraulic communication with a main bore and pressure chamber of said valve train, the module comprising: a) a module body; b) an accumulation piston extendable from said module body and slidably disposable in said lost motion bore to provide a lost-motion volume for hydraulic fluid in said lost-motion bore on a first side of said accumulation piston, and defining a well in said module body adjacent a second side of said accumulation piston; c) a control chamber formed in said module body and fillable with a hydraulic fluid; d) a servo-valve disposed in a passage in said body hydraulically connecting said control chamber to a sump; e) a control piston extending from said second side of said accumulation piston into said control chamber, wherein closing of said passage by said servo-valve causes said control chamber to be made hydraulically rigid by preventing flow of hydraulic fluid from said control chamber to said sump, thereby preventing said control piston and said accumulation piston from moving in said lost-motion bore, and wherein opening of said passage by said servo-valve causes said control chamber to be made hydraulically fluid by allowing flow of hydraulic fluid from said control chamber to said sump, thereby permitting said control piston and said accumulation piston to move in said lost-motion bore.