During the development of their boiler, control system, and steam engines a considerable number of patents were filed. The early patents from 1904 were co-authored by John Henry Sheppee with John Edward Gibbs (GB190414240, GB190427735, GB190427736, GB190427737, GB190427738, GB190515105, GB190612308, GB190614870, GB190614872), with others named on patents being Francis Faulkner Sheppee (his father) (GB190606570), Edward Cyril Bowden-Smith (GB190613384, FR378514, GB190711171, GB190720179), Maurice Walker Shippey (GB190809492, GB191013098), Edgell William Sheppee (his brother)(GB191303237, GB191303236) and Samuel George Jowitt (from GB191423737 through to 1939, though these related to other developments). Another patent without co-authors (GB190810851) reveals that the use of the high pressure, high temperature steam required the steam engine to use poppet valves (as used in internal combustion engines) - there were also problems with cylinder castings cracking due to thermal expansion stresses which were overcome by using cylinders that were tubular sandwiched between cylinder head castings, with the valves operating in the head/s.
