An apparatus such as a hot gas engine and a compressor has a rolling diaphragm seal between adjacent walls of a piston and cylinder and supported by a liquid, and has an additional piston ring seal between the diaphragm seal and gas space above, this ring seal having an operative diameter equal to the effective diameter of the diaphragm seal for maintaining constant the volume above said diaphragm seal.
The guide portion of the cylinder of a Stirling cycle device is located at least partially within and is axially coextensive with the bellows thereby providing a reduction in the height/length of the piston, cylinder and bellows assemblies. The reduction is the distance between the guide surface and the top of the piston reduces the moment arm for canting.
A Stirling engine wherein a pressure variation is provided by a reciprocative movement of a displacer and is effected upon a power piston to obtain an output motive force. A first elastic film is provided at the displacer rod projecting into the crankcase so as to produce a first hermetically sealed space bounded by the expansion cylinder. A second elastic film is provided at the power piston rod so as to produce a second hermetically sealed space below the power piston. A pressure adjusting device equalizes the mean pressure of a reactive space, which includes the first and the second hermetically sealed spaces, and that of the crankcase.
A leakage gas return device for a Stirling engine includes a pumping cylinder divided into first and second chambers by a piston, one of the chambers for receiving leakage gas from the block seal through a first one way valve and returning the leakage gas to the engine cylinder through a second one way valve. The other chamber is first connected to a low pressure oil source to permit expansion of the first chamber by the leakage gas, and at bottom dead center the second chamber is connected to a high pressure oil source to thereby force the leakage gas back into the engine cylinder.
The publication relates to a power converter according to the principle of the hot-air engine (Stirling engine), comprising a cylinder containing a main piston (4) and a displacement piston (3), each of which can be moved forward and backward on the axis of the cylinder and each of which possesses a piston rod assembly (20, 25) which is connected via connecting rods (17, 21) with a link system (21-24 or 17-19 resp.) to two parallel cranks (9) which rotate synchronously in opposite directions so that the displacement piston is moved phase-shifted to the main piston. The link system (21-24) of the main piston (4) comprises a frame element (24) which is rigidly connected to the latter's piston rod assembly (25) and has at least four journals (22,23) which are arranged symmetrically to the cylinder axis in a common plane perpendicular to the cylinder axis and which are oriented parallel to the crank shafts (9) and to each of which is linked a connecting rod (21). The link system (17-19) and/or the piston rod assembly (20) of the displacement piston (3) is/are passed through the frame element (24), and the cranks are constructed as crank shafts (9), on each of which the connecting rods (17, 21) act on a right angle bend (16, 14, 15) positioned between two, each, crank shaft bearings (11, 12). The right angle bends (14, or 16 and 15 resp.) of the crank shafts (9) which are connected to the link system (21-24) of the main piston (4) or which are respectively connected to the link system of the displacement piston (3) are off-set at angles to each other.
Means are provided to enable the main water pump of a Stirling engine to act as a mini-pump to cool the roll sock seals or rolling diaphragms when the engine is not running.
