Two-stroke cycle internal combustion engine

In a two-stroke cycle internal combustion engine having a crankshaft, at least one connecting rod pivotally connected at one end to the crankshaft, fuel induction means and ignition means, the improvement which comprises:

• a cylinder having a head end and a rearward end closure, a sealed passage in said closure,
• a reciprocating piston in said cylinder and defining therewith a combustion chamber and a charging chamber as the piston moves between its top dead center position and its bottom dead center position,
• a plurality of radial inlet ports formed in the cylinder so as to be normally closed by said piston and being open to said charging chamber when said piston is in its top dead center position,
• a plurality of radial exhaust ports formed in the cylinder so as to be normally closed by said piston and being open to said combustion chamber when said piston is in its bottom dead center position,
• means formed in said piston defining an axial valve port between said charging chamber and said combustion chamber and forming a valve seat and,
• an operating rod axially mounted in said cylinder and extending through said sealed axial passage in said rearward end closure of said cylinder, said operating rod being pivotally connected at its outer end to said connecting rod and having a valve head formed on its inner end to sealingly engage said valve seat and close said valve port,
• said piston and operating rod being forced by fluid pressure into valve-closing engagement during the operating cycles of the engine, except for a portion of each operating cycle when the piston passes through its bottom dead center position wherein retraction movement is limited by fluid pressure caused by compressed gas in said charging chamber, and said operating rod is further retracted by said crankshaft and said connecting rod to open said valve port to admit a charge from said charging chamber to said combustion chamber.

A two-stroke cycle internal combustion engine having a crankshaft, a cylinder with a cylinder head, a piston in said cylinder, a driving connection including a piston rod between said piston and said crankshaft whereby rotary crankshaft motion is developed by reciprocating motion of said piston;

• said piston and said cylinder defining a combustion chamber of variable volume between said piston and said cylinder head, a radial flow exhaust gas port in said cylinder at a first location, a radial flow inlet gas charge port in said cylinder at a second location;
• said piston being positioned in said cylinder and adapted to cover said exhaust port and to uncover said inlet port when said piston approaches its top dead center position;
• said piston being adapted to cover said inlet port and to uncover said exhaust port when said piston approaches its bottom dead center position;
• and charge valve means in said piston responsive to movement of said piston rod when said piston uncovers said exhaust ports for discharging a gas charge into said combustion chamber.

A two-stroke cycle internal combustion engine having a crankshaft and a cylinder;

• a double acting piston in said cylinder, a cylinder head at one end of said cylinder, said piston and said cylinder head forming with said cylinder a fuel combustion chamber on one side of said piston;
• a gas charge chamber defined in part by said piston and said cylinder on the opposite side of said piston;
• a radial flow exhaust port in said cylinder;
• a radial flow gas charge port in said cylinder spaced axially from said exhaust port;
• said piston covering said exhaust port during expansion of said combustion chamber upon movement of said piston away from said cylinder head and uncovering said exhaust port when said piston approaches its bottom dead center position;
• said piston covering said charge port during expansion of said charge chamber upon movement of said piston toward said cylinder head and opening said charge port when said piston approaches its top dead center position;
• means for connecting said piston to said crankshaft including a piston rod and a lost motion connection between said piston rod and said piston;
• a charge valve port in said piston between said combustion chamber and said charge chamber, said piston rod and said piston having registering valve portions adapted to control the opening and closing of said charge valve port in response to changes in the pressure differential acting on said piston.