Patent EP-0085427-A1 (EP)
Inventor: ROSER WALTER
IPC: F01C19/02
Filed: 1983-02-01
Abstract: 1. Four-stroke internal combustion engine, wherein two disc-shaped rotary pistons are provided each of which is mounted, seated on the motor shaft extending through the piston chambers, in a piston chamber corresponding to the thickness of the piston and having a circular cylindrical path of revolution for the piston, the first piston chamber being connected to a suction union for the fuel-air mixture, the second piston chamber to an exhaust port for the expanded combustion gases, and both piston chambers being connected to one another via ducts which have valves arranged therein and which are connected to a chamber for the ignition of the fuel-air mixture, the rotary piston provided in the first piston chamber being constructed as an eccentric piston with such a peripheral form that the eccentric piston is, with that axis-parallel line of its outer periphery which is at the greatest distance from the rotary axis, during its rotary movement in contact with the path of revolution of the first piston chamber, there being provided at the first piston chamber between the suction union and the mouth of the connecting duct from the ignition chamber into the first piston chamber, a slide valve which extends into the first piston chamber and bears slidably against the outer surface of the eccentric piston under the action of a spring force, and which during piston rotation forms together with the contact line of the eccentric piston on the path of revolution a variable suction chamber and a variable compression chamber, and the rotary piston in the second piston chamber being under the influence of the explosion gases after ignition of the fuel-air mixture up to the exhaust operation, characterised by the combination of the following features : a) the construction of the chamber provided for ignition as an invariable-volume combustion chamber (15), b) the arrangement of a pivotable valve (17) which masks the opening of the combustion chamber (15) towards the second piston chamber (2) at least fot the duration of the transfer operation of the compressed gas from the first piston chamber (1) into the combustion chamber (15), c) the construction of a part of the peripheral surface of the concentrically mounted second piston (4) acting as the working piston as a part of a circular cylindrical shell (19) whose radius corresponds with slight play to the path of revolution (12) for the working piston (4), as support for the outwardly pivotable end of the pivotable valve (17) in the closure position, d) the dimensioning of the circular cylindrical portion of the peripheral surface of the working piston (4) in such a manner that the length of time during which the outwardly pivotable end of the pivotable valve (17) bears on the periphery of the circular cylindrical portion (19) corresponds to the duration of the compression from the opening of a valve (16a) dependent on time or pressure and arranged in the transfer duct (16) from the first piston chamber (1) into the combustion chamber (15), up to the attainment of the predetermined compression ratio, e) the arrangement of the working piston (4) relatively to the eccentric piston (3) on the motor shaft (5) such that the working piston (4) engages behind the pivotable valve (17) during the duration of the inflow of the compressed mixture into the combustion chamber (15) and presses on the valve seat (31) which is provided at the edge of the combustion chamber (15) opposite the second piston chamber (2), f) the arrangement of a plane surface, which as viewed in the direction of rotation of the working piston (4) at the end of the circular cylindrical portion (19) of the outer surface extends from this outer chamber of the working piston (4) into the second piston surface (2), as a collecting surface (33) for the explosion gases produced at the ignition of the compressed gases in the combustion chamber (15), and such arrangement allows at the same time a limited pivoting movement of the pivotable valve (17) under the influence of the explosion gases out of the closure position relatively to the combustion chamber (15), the width of this plane surface corresponding to the piston disc thickness and its length being not greater than the length of the combustion chamber opening at right angles to the piston axis, g) the shaping of the portion (29) of the outer surface of the working piston (4) between the end of the collecting surface (33) which extends into the piston chamber (2) up to the start of the circular cylindrical portion (19) of the outer surface of the working piston (4) as considered in the direction of rotation in such a manner that in the portion (39) the outer surface which engages behind the pivoted-out end of the pivotable valve (17) in the opened position merges in a continuous curve into the circular cylindrical portion (19) of the outer surface of the working piston (4), h) the arrangement of a sealing strip in each case (23 and 35) on the eccentric piston (3) at the place where there is the greatest distance between the outer surface of the eccentric piston (3) and its axis of rotation, and on the working piston (4) at the edge which is formed by the collecting surface (33) for the explosion gases and the circular cylindrical portion (19) of the outer surface of the working piston (4).