An engine (2) is a four-flow scavenging type engine. Four scavenging ports (34) include: first right and left scavenging ports (34(lef-1) and 34(ref-1)) that lie on a side relatively away from an exhaust port (22) and that lie facing each other with a cylinder (4) in between; and second right and left scavenging ports (34(lef-2) and 34(ref-2)) that lie closer to the exhaust port (22) than first right and left scavenging ports do and that lie facing each other with the cylinder (4) in between. The second left scavenging port and the first right scavenging port that make up a first mutually diagonal set (Diag-No. 1) have different opening timings from those of the first left scavenging port and the second right scavenging port that make up a second mutually diagonal set (Diag-No. 2).

An engine (2) is a four-flow scavenging type engine. Four scavenging ports (34) include: first right and left scavenging ports (34(lef-1) and 34(ref-1)) that lie on a side relatively away from an exhaust port (22) and that lie facing each other with a cylinder (4) in between; and second right and left scavenging ports (34(lef-2) and 34(ref-2)) that lie closer to the exhaust port (22) than first right and left scavenging ports do and that lie facing each other with the cylinder (4) in between. The second left scavenging port and the first right scavenging port that make up a first mutually diagonal set (Diag-No. 1) have different opening timings from those of the first left scavenging port and the second right scavenging port that make up a second mutually diagonal set (Diag-No. 2).

A valve system/method suitable for an internal combustion engine (ICE), compressor pump, vacuum pump, and/or reciprocating mechanical device is disclosed. The system/method is optimized for construction of a four-stroke ICE. The rudimentary system incorporates a unitized intake and exhaust engine block cover (UEC) that enclose an intake rotary valve cylinder (IVC) and exhaust rotary valve cylinder (EVC) that control intake/exhaust flow through a respective intake rotary valve port (IVP) and an exhaust rotary valve port (EVP) into and out of a combustion cylinder that provides power to a piston and crankshaft. An intake multi-staged valve (IMV) and exhaust multi-staged valve (EMV) provide intake and exhaust flow control for the IVC/IVP and EVC/EVP. An enhanced system may include a variety of intake/exhaust port seals (IPS/EPS), forced induction (FIN), forced discharge (FID), centrifugal advance (CAD), and/or cooling channel spool (ICS/ECS).

A valve system/method suitable for an internal combustion engine (ICE), compressor pump, vacuum pump, and/or reciprocating mechanical device is disclosed. The system/method is optimized for construction of a four-stroke ICE. The rudimentary system incorporates a unitized intake and exhaust engine block cover (UEC) that enclose an intake rotary valve cylinder (IVC) and exhaust rotary valve cylinder (EVC) that control intake/exhaust flow through a respective intake rotary valve port (IVP) and an exhaust rotary valve port (EVP) into and out of a combustion cylinder that provides power to a piston and crankshaft. An intake multi-staged valve (IMV) and exhaust multi-staged valve (EMV) provide intake and exhaust flow control for the IVC/IVP and EVC/EVP. An enhanced system may include a variety of intake/exhaust port seals (IPS/EPS), forced induction (FIN), forced discharge (FID), centrifugal advance (CAD), and/or cooling channel spool (ICS/ECS).

A valve system/method suitable for an internal combustion engine (ICE), compressor pump, vacuum pump, and/or reciprocating mechanical device is disclosed. The system/method is optimized for construction of a four-stroke ICE. The rudimentary system incorporates an intake engine block cover (IEC) and exhaust engine block cover (EEC) that enclose an intake rotary valve disc (IVD) and exhaust rotary valve disc (EVD) that control intake/exhaust flow through a respective intake rotary valve port (IVP) and an exhaust rotary valve port (EVP) into and out of a combustion cylinder that provides power to a piston and crankshaft. An intake multi-staged valve (IMV) and exhaust multi-staged valve (EMV) provide intake and exhaust flow control for the IVD/IVP and EVD/EVP. An enhanced system may include a variety of intake/exhaust port seals (IPS/EPS), forced induction/discharge (FIN), centrifugal advance (CAD), and/or cooling channel spool (ICS/ECS).

A valve system/method suitable for an internal combustion engine (ICE), compressor pump, vacuum pump, and/or reciprocating mechanical device is disclosed. The system/method is optimized for construction of a four-stroke ICE. The rudimentary system incorporates an intake engine block cover (IEC) and exhaust engine block cover (EEC) that enclose an intake rotary valve disc (IVD) and exhaust rotary valve disc (EVD) that control intake/exhaust flow through a respective intake rotary valve port (IVP) and an exhaust rotary valve port (EVP) into and out of a combustion cylinder that provides power to a piston and crankshaft. An intake multi-staged valve (IMV) and exhaust multi-staged valve (EMV) provide intake and exhaust flow control for the IVD/IVP and EVD/EVP. An enhanced system may include a variety of intake/exhaust port seals (IPS/EPS), forced induction/discharge (FIN), centrifugal advance (CAD), and/or cooling channel spool (ICS/ECS).

A valve system/method suitable for an internal combustion engine (ICE), compressor pump, vacuum pump, and/or reciprocating mechanical device is disclosed. The system/method is optimized for construction of a two-stroke ICE. The rudimentary system incorporates an intake engine block cover (IEC) and exhaust engine block cover (EEC) that enclose an intake rotary valve cylinder (IVC) and exhaust rotary valve cylinder (EVC) that control intake/exhaust flow through a respective intake rotary valve port (IVP) and an exhaust rotary valve port (EVP) into and out of a combustion cylinder that provides power to a piston and crankshaft. Intake/exhaust multi-staged valves (IMV/EMV) provide intake/exhaust flow control for the IVC/IVP and EVC/EVP. An enhanced system may include a variety of intake/exhaust port seals (IPS/EPS), forced induction/discharge (FIN/FID), centrifugal advance (CAD/ICA/ECA), and/or cooling channel spool (ICS/ECS).

A valve system/method suitable for an internal combustion engine (ICE), compressor pump, vacuum pump, and/or reciprocating mechanical device is disclosed. The system/method is optimized for construction of a two-stroke ICE. The rudimentary system incorporates an intake engine block cover (IEC) and exhaust engine block cover (EEC) that enclose an intake rotary valve cylinder (IVC) and exhaust rotary valve cylinder (EVC) that control intake/exhaust flow through a respective intake rotary valve port (IVP) and an exhaust rotary valve port (EVP) into and out of a combustion cylinder that provides power to a piston and crankshaft. Intake/exhaust multi-staged valves (IMV/EMV) provide intake/exhaust flow control for the IVC/IVP and EVC/EVP. An enhanced system may include a variety of intake/exhaust port seals (IPS/EPS), forced induction/discharge (FIN/FID), centrifugal advance (CAD/ICA/ECA), and/or cooling channel spool (ICS/ECS).

Two-cycle engine includes cylinder block formed with a cylinder and crank chamber. The cylinder block includes: an exhaust passage leading to a combustion chamber in the cylinder through an exhaust port opened to an inner circumferential surface of the cylinder; a scavenging port opened to the inner circumferential surface of the cylinder; a communication passage extending from the scavenging port in a radial direction of the cylinder; and a scavenging passage extending in an axial direction of the cylinder, communicating with the crank chamber, and having an opening portion formed in a bottom surface of the communication passage. A ceiling surface of the communication passage is inclined toward a cylinder head with increasing distance from a scavenging passage side thereof toward the scavenging port. A bottom surface of the communication passage is inclined toward the crank chamber with increasing distance from a scavenging passage side thereof toward the scavenging port.

Two-cycle engine includes cylinder block formed with a cylinder and crank chamber. The cylinder block includes: an exhaust passage leading to a combustion chamber in the cylinder through an exhaust port opened to an inner circumferential surface of the cylinder; a scavenging port opened to the inner circumferential surface of the cylinder; a communication passage extending from the scavenging port in a radial direction of the cylinder; and a scavenging passage extending in an axial direction of the cylinder, communicating with the crank chamber, and having an opening portion formed in a bottom surface of the communication passage. A ceiling surface of the communication passage is inclined toward a cylinder head with increasing distance from a scavenging passage side thereof toward the scavenging port. A bottom surface of the communication passage is inclined toward the crank chamber with increasing distance from a scavenging passage side thereof toward the scavenging port.