Patent ID: 8151746
Filing Date: 2012-04-10
Classification: F02B,F02D

Abstract:
1. An improved control system for an adjustment device for a variable compression ratio engine comprising: a jack head; a jack piston received within a chamber of the jack head defining a first fluid chamber and a second fluid chamber and having a first bore for receiving a jack rod and a second bore; a sprocket wheel mounted to a crankshaft and with a first set of teeth engaging a control rack fixed to the jack rod and a second set of teeth; a movable transmission member attached to a cylinder engaging the second set of teeth of the sprocket wheel, the improvement comprising: a control rack rod received by the second bore of the chamber of the jack head a control valve for controlling the flow of fluid between the first fluid chamber and the second fluid chamber comprising a spool with a plurality of lands slidably received within a bore of the jack head; wherein when the spool of the control valve is in a first position, fluid from the first fluid chamber exits from the first fluid chamber through the spool of the control valve to the second fluid chamber, moving the jack piston and control rack, such that the sprocket wheel undergoes a reciprocating motion, moving the cylinder to a first position; wherein when the spool of the control valve is in a second position, fluid from the second fluid chamber exits from the second fluid chamber through the spool of the control valve to the first fluid chamber, moving the jack piston and control rack, such that the sprocket wheel undergoes a reciprocating motion, moving the cylinder to a second position; and wherein when the spool of the control valve is in a third position, fluid is provided to the first fluid chamber and the second fluid chamber only, holding or maintaining position of the jack piston within the chamber of the jack head.