Ball piston engine

The Ball piston engine (Wolfhart engine) is an [[internal combustion engine|internal combustion]] rotary engine that uses two intertwined rotors instead of reciprocating pistons. It was invented by German physicist Wolfhart Willimczik. A spherical piston rotates in combination with a spherical housing, whereby the rotational axes incline towards each other slightly. In these way “strokes” are created within the rotational system generating periodic volumetric changes in the 2 working chambers adjacent to the dividing wall. Every nutation can be described as two oscillations around two axes perpendicular to each other. One generates the stroke motion, the other generates a rocking motion of the edge of the piston what allowed the closing of the exhaust before opening the opening for fresh gas, ergo an unsymmetrical control table as possible by four stroke engines only. It works as a two stroke engine without any valves, but with unsymmetrical control times and direct lubrication as an four stroke engine. It has the best possible kinematic as rotary piston machine with rotations only around the centers of gravity (no orbiting parts). This engine unifies the advantages of al three categories. Purpose of this invention was to overcome the shortcomings of the Wankel engine, especially to avoid high sliding speed of the sealing parts. Here is the sliding speed in the same range as by a classical piston engine. Higher sustained rotating speeds are possible due to the absence of oscillating inertial forces.