Internal combustion engine

An internal combustion engine comprising a first set of cylinders comprising:

• a first two-stroke compression cylinder housing a first compression piston connected to a first crank shaft;
• an intermediate two-stroke compression cylinder housing an intermediate compression piston, wherein the intermediate two-stroke compression cylinder is configured to receive compressed gas from the first two-stroke compression cylinder;
• and
• a first four-stroke combustion cylinder housing a first combustion piston, wherein the first four-stroke combustion cylinder is configured to receive compressed gas from the intermediate two-stroke-compression cylinder;
• wherein the internal combustion engine further comprises a second set of cylinders comprising:
• a second two-stroke compression cylinder housing a second compression piston connected to the first crank shaft, wherein the second two-stroke compression cylinder is configured to provide compressed gas to the intermediate two-stroke compression cylinder;
• and
• a second four-stroke combustion cylinder housing a second combustion piston, wherein the second four-stroke combustion cylinder is configured to receive compressed gas from the intermediate two-stroke compression cylinder;
• wherein each one of the intermediate compression piston and the first and second combustion pistons are connected to a second crank shaft, the second crank shaft being configured to rotate with a speed of at least twice the speed of the first crank shaft,
• and further comprising:
• a first two-stroke expansion cylinder housing a first expansion piston connected to the first crank shaft, the first two-stroke expansion cylinder being configured to receive exhaust gas from the first four-stroke combustion cylinder;
• and
• a second two-stroke expansion cylinder housing a second expansion piston connected to the first crank shaft, the second two-stroke expansion cylinder being configured to receive exhaust gas from the second four-stroke combustion cylinder.

An internal combustion engine comprising a first set of cylinders comprising:

• a first two-stroke compression cylinder housing a first compression piston connected to a first crank shaft;
• an intermediate two-stroke compression cylinder housing an intermediate compression piston, wherein the intermediate two-stroke compression cylinder is configured to receive compressed gas from the first two-stroke compression cylinder;
• and
• a first four-stroke combustion cylinder housing a first combustion piston, wherein the first four-stroke combustion cylinder is configured to receive compressed gas from the intermediate two-stroke-compression cylinder;
• wherein the internal combustion engine further comprises a second set of cylinders comprising:
• a second two-stroke compression cylinder housing a second compression piston connected to the first crank shaft, wherein the second two-stroke compression cylinder is configured to provide compressed gas to the intermediate two-stroke compression cylinder;
• and
• a second four-stroke combustion cylinder housing a second combustion piston, wherein the second four-stroke combustion cylinder is configured to receive compressed gas from the intermediate two-stroke compression cylinder;
• wherein each one of the intermediate compression piston and the first and second combustion pistons are connected to a second crank shaft, the second crank shaft being configured to rotate with a speed of at least twice the speed of the first crank shaft, and wherein the intermediate compression piston and the first combustion piston are arranged in a 180 degrees crank angle offset in relation to each other, such that the intermediate compression piston is configured to reach an upper en position within the intermediate compression cylinder when the first combustion piston reaches a lower end position within the first combustion cylinder.