Patent ID: 8322128

Claim:
A hydrogen engine using a recirculating working medium, wherein hydrogen, oxygen, and a working medium composed of a monoatomic gas is supplied to a combustion chamber to combust the hydrogen, and the working medium included in an exhaust gas discharged from the combustion chamber is recirculated to the combustion chamber through a recirculating passage, the hydrogen engine having product eliminating means, disposed in the recirculating passage, for eliminating carbon dioxide produced in the combustion chamber, wherein the product eliminating means comprises: an absorbing material configured to absorb the carbon dioxide; and a discharging opening section configured to discharge the carbon dioxide from the absorbing material to ambient air outside of the hydrogen engine, wherein the recirculating passage comprises a main passage and a bypass passage which branches from the main passage at a branch point and joins to the main passage at a joining point downstream of the branch point, and the product eliminating means is disposed in the bypass passage, the hydrogen engine further comprising a path switching means, disposed at the branch point, for selecting either a first state in which the gas flowing through the main passage upstream of the branch point is made to flow through the main passage from the branch point to the joining point or a second state in which the gas flowing through the main passage upstream of the branch point is made to flow through the bypass passage from the branch point to the joining point.