Rotary piston machine

A rotary piston machine 10 includes an enclosure 12 having a cavity 14 therein with arcuate side walls 16a,b,c defining a plurality of arcuate recesses 18a,b,c and a piston member 20 rotationally disposed in the cavity 14. The piston member 20 includes opposite ends 42 and 43 configured to rotationally engage the arcuate side walls 16a,b,c and the arcuate recesses 18a,b,c such that compression chambers 26a,b,c are ultimately formed via the piston member ends 42 and 43 cooperatively engaging two arcuate recesses 18a,b,c. The two piston member ends 42 and 43 each including first and second arcuate edges 44 and 46 that sequentially engage cooperating first and second edge portions 50a,b,c and 52a,b,c of respective arcuate recesses 18a,b,c, resulting in two relatively large seals between one end of the piston member 20 and an arcuate recess 18a,b,c during rotation of the piston member 20 until forming compression chambers 26a,b,c, thereby preventing a fuel-air mixture from "leaking" during the formation of the compression chambers 26a,b,c, resulting in maximum power output from the rotary piston machine 10.