Piston engine comprising member to cover bottom face of valve head of poppet valve

A piston engine with a member to cover a bottom face of a valve head of a poppet valve, comprising:

• a combustion chamber defined between a piston and a cylinder head, in which the combustion chamber further extends outside a main cylinder;
• an inner wall of the combustion chamber, comprising a first part and a second part, the first part being a part facing with an upper face of the piston provided inside the main cylinder, the second part being an extended part outside the main cylinder
• a sub cylinder provided outside the main cylinder;
• the poppet valve provided on the second part, the poppet valve being provided with a second drive unit to drive a stem of the poppet valve;
• the member to cover the bottom face of the valve head of the poppet valve, in which the member reciprocates in the sub cylinder and comprises a cylindrical side face, in which the valve head is located between a second valve sheet of the poppet valve and the member;
• a means to make the second valve sheet, the valve head and the member contact closely one another, in which the second drive unit and the means drive the poppet valve and the member integrally, in which the member abuts the bottom face of the poppet valve;
• a compression ring provided at a position wedged between an inner wall of the sub cylinder and the cylindrical side face of the member;
• and
• an overhead valve provided on the first part, in which a gas passes through the a gap between the overhead valve and a first valve sheet of the overhead valve when the overhead valve is open, in which the overhead valve is provided with a first spring and a first drive unit,
• wherein a combination of the overhead valve and the poppet valve includes at least one intake valve and one exhaust valve,
• a plurality of the poppet valve are provided on the second part, all of the plurality of poppet valves provided on the second part being exhaust poppet valves, and
• at least one of the overhead valve provided on the first part is an intake valve.

A piston engine with a member to cover a bottom face of a valve head of a poppet valve, comprising:

• a combustion chamber defined between a piston and a cylinder head, in which the combustion chamber further extends outside a main cylinder;
• an inner wall of the combustion chamber, comprising a first part and a second part, the first part being a part facing with an upper face of the piston provided inside the main cylinder, the second part being an extended part outside the main cylinder;
• a sub cylinder provided outside the main cylinder;
• the poppet valve provided on the second part, the poppet valve being provided with a second drive unit to drive a stem of the poppet valve, in which a gas passes through a gap between the poppet valve and a second valve sheet of the poppet valve when the poppet valve is open;
• the member to cover the bottom face of the valve head of the poppet valve, in which the member reciprocates in the sub cylinder and comprises a cylindrical side face, in which the valve head is located between the second valve sheet of the poppet valve and the member;
• a means to make the second valve sheet, the valve head and the member contact closely one another, in which the second drive unit and the means drive the poppet valve and the member integrally, in which the member abuts the bottom face of the poppet valve;
• a compression ring provided at a position between an inner wall of the sub cylinder and the cylindrical side face of the member;
• and
• at least one or more overhead valve provided on the first part, all of the overhead valve provided on the first part being an intake overhead valve, in which the overhead valve is provided with a first spring and a first drive unit,
• wherein the total number of the overhead valve and the poppet valve is not less than 3, and
• an exhaust poppet valve is provided on the second part.