A Stirling refrigerator (1), which prevents oil rising, and includes a housing (2), cylinder (17,18), piston (19,25), piston rod (21,27) and an oil seal bellows (22,28). The oil seal bellows (22,28) seals a space between the housing (2) and the cylinder (1...

The heat-creating burner (28) has a a heater (23) and a combustion chamber (30). It runs on a flame-free oxidation basis, so that the creation of thermal nitrogen oxides is suppressed. By this means, the content of such oxides in the exhaust gas is reduced...

The invention generates mechanical energy and electrical energy efficiently, by combining a Stirling engine and a fuel cell. To achieve this, a solid electrolyte type fuel cell FC is disposed between an air passage 35 for supplying air to a heater 24 of a ...

The piston and cylinder unit includes a piston with at least one piston ring groove (35). The spacing between the piston ring groove closest to the crankshaft and the bottom edge (43) of the piston body (41) is between 0.66 and 1.5 times the piston stroke,...

The boiler comprises a common heat exchanger (30) and two burners (10, 20). They occupy individual combustion chambers (11, 21) and are designed for different heating outputs. They heat different regions (30.1, 30.2) of the common heat exchanger, and/or ar...