Abstract: Liquid-cooled rotary piston internal combustion engine with a housing consisting of at least one annular shell with interior guideway and two parallel end pieces, and bounding an interior space. The shell and end pieces containing cavities for circulation of two cooling circuits completely separate from each other. One of the circuits cools the region of the housing in the hot arc of the shell, where the ignition, expansion and exhaust strokes take place in the interior space. A liquid-cooled piston revolves in the housing. The cooling circuit of the piston and the shell cooling circuit traversing the region of the hot arc are connected in series.

Abstract: A rotary piston internal combustion engine of the trochoidal type with a housing. The engine includes at least one peripheral wall portion and at least two parallel side portions and has induction and exhaust ports. Each peripheral wall portion and two associated side portions define a cavity in which a multi-apex piston is rotatably mounted to define variable volume working chambers. The piston is provided with seal elements which are in sliding engagement with the inner surfaces of the housing. The seal elements are provided with a passage for lubricating the inner surfaces of the housing with the passage opening into the cavity in the neighborhood of each induction port in the region of that working chamber which is undergoing the induction phase. The passage is in communication with the atmosphere and has a lubricant feed pipe opening into it. A restriction is provided in the passage between its point of entry into the cavity and the point of entry of the lubricant feed pipe.