Did a quick patent search and found the following? 1 2011901910 Advanced Linear Convergent Piston Engine Manthey Redmond (Aust) Pty Ltd Manthey, Steven Charles 2011-05-18 WITHDRAWN 2 2010904441 Linear Convergent Piston Engine Manthey Redmond (Aust) Pty Ltd Manthey, Steven Charles 2010-10-04 WITHDRAWN 3 2009903136 Linear convergent engine Manthey Redmond (Aust) Pty Ltd Manthey, Steven Charles 2009-07-06 WITHDRAWN