Abstract: A rotary gear pump comprises a housing and at least a pair of rotatable, meshing gears positioned within the housing. The meshing gears define spaced teeth which extend helically in the general direction of the axis of each gear rotation. A flow inlet and flow outlet are provided, each positioned in the housing to permit flow of fluid substantially longitudinally of the rotation axes between the meshing gears as the gears rotate said teeth through a tooth-meshing area. At least one first vane covers the teeth of each gear at a rotational position upstream of the tooth-meshing area, to shield the covered teeth from an energy-consuming backflow of fluid from said tooth-meshing area as the gears rotate. Also, fixed-volume furnaces are used to receive and distribute compressed, burning gases from closing chambers formed between the teeth to opening chambers across the top dead center position.

Abstract: A propeller for fluid propulsion comprises a pair of substantially rigid blades which rotate about their longest dimension in opposite directions, the blades each being oppositely helically twisted along the longest blade dimension and positioned together in synchronously opposite, rotatable condition, with the rotating blades passing by each other in closely spaced relation substantially without physical contact. The blades occupy a tubular housing enclosing the rotating blades in closely-spaced relation between the housing and blades. Further sealing is provided by each blade side carrying a hemicylindrical wall with a concave side facing outwardly, each hemicylindrical wall being helically twisted in a manner identical to the helical twist of the blade. The hemicylindrical walls have a cross-sectional diameter that permits, upon blade rotation, an edge of the other blade to sweep across the concave side of each hemicylindrical wall in closely spaced relation for sealing purposes.