Rotary valve system and engine using the same

An internal combustion engine having compression and expansion pistons constrained for reciprocating movement within compression and expansion chambers, a combustion chamber in which air from the compression chamber is combined with fuel and burned to produce an increased gas volume, an intake valve for controlling airflow to the compression chamber, and outlet valve for controlling air flow from the compression chamber to the combustion chamber, an inlet valve for controlling communication between the combustion chamber and the expansion chamber, and an exhaust valve for controlling exhaust gas flow from the expansion chamber, at least one of the valves comprising an outer valve member which is rotatively mounted in a bore and has an opening which moves into and out of communication with the chamber as the outer valve member rotates, an inner valve member rotatably mounted within the outer valve member with an opening at least partly overlapping the opening in the outer valve member, a first drive gear affixed to the inner valve member, a second drive gear affixed to the outer valve member, and a variable gear train interconnecting the drive gears for rotation in unison while permitting the drive gears to be advanced and retarded relative to each other to change the degree of overlap between the openings and thereby control the timing and duration of communication between the openings and the port.

A rotary valve system for controlling communication with a port in an internal combustion engine, comprising:

• a first rotary valve member having an opening which comes into registration with the port during part of each revolution of the valve member;
• a second rotary valve member disposed concentrically of the first valve member and having an opening which at least partly overlaps with the opening in the first valve member;
• and
• a first drive gear affixed to the first valve member, a second drive gear affixed to the second valve member, and a variable gear train interconnecting the drive gears for rotation in unison while permitting the drive gears to be advanced and retarded relative to each other to change the degree of overlap between the openings and thereby control the timing and duration of communication between the openings and the port.