Valve Assembly and Method for High Temperature Engines

A valve assembly for controlling communication with a chamber in an engine, comprising a valve body having an inlet and outlet ports, a valve seat surrounding one of the ports, a pivotally mounted lever arm extending into the valve body, a valve member connected to the lever arm within the valve body, an actuator connected to the lever arm outside the valve body for moving the valve member between open and closed positions relative to the valve seat, and a pilot valve which can be opened to allow gas to bypass the valve member and thereby reduce the pressure against which the valve member must be moved.

A valve assembly in an engine having a compression cylinder, an expansion cylinder, pistons for varying the volumes of the compression and expansion cylinders, and a heat exchanger in which working fluid from the compression cylinder is heated to a high temperature and pressure for delivery to the expansion cylinder, comprising:

• a valve body with an inlet port in communication with the combustion chamber and an outlet port in communication with the expansion cylinder, a valve seat surrounding the outlet port, a pivotally mounted lever arm extending into the valve body between the inlet and outlet ports, a valve member connected to the lever arm near the valve seat, and an actuator connected to the lever arm outside the valve body for moving the valve member between open and closed positions relative to the valve seat

A method of controlling flow of high temperature, high pressure gases, comprising the steps of:

• passing the high temperature, high pressure gases through a chamber having inlet and outlet ports with a valve seat surrounding one of the ports and a valve member connected to a pivotally mounted lever arm within the chamber, and actuating the lever arm from outside the first chamber, away from the high temperature, high pressure gases, to move the valve member between open and closed positions relative to the output port.

A valve assembly, comprising a body having an internal chamber with inlet and outlet ports through which hot gases flow, a valve seat with a sealing surface surrounding one of the ports, a pivotally mounted lever arm extending into the chamber for movement about a first axis perpendicular to the lever arm, a valve member connected to the lever arm within the chamber for pivotal movement about the axis of the lever arm and about an axis perpendicular to the lever arm and parallel to the sealing surface, and an actuator connected to the lever arm outside the valve body, away from the hot gases, for pivoting the lever arm about the first axis to move the valve member between open and closed positions relative to the valve seat.