GB1408236A - Method and positive-displacement engine for converting one form of energy into another form of energy - Google Patents

Abstract

1408236 Rotary positive-displacement machine BATTELLE DEVELOPMENT CORP 19 Jan 1973 [31 Jan 1972] 2928/73 Heading F1F In a heat engine spherical free-pistons 16 are propelled anti-clockwise along an endless passageway 12 by an expanding hot gas e.g. air, which is introduced, either initially or continually, in a compressed state through a tube 18, heated by a coil 20 and either ejected (after expansion) through an outlet 22 or cooled in that region, useful energy being produced by the pistons in the form of electric pulses induced in a coil 40 of a linear generator 37 and/or air inducted through an inlet 24 and compressed into a vessel 42. Reverse piston motion is prevented by ratchet-controlled wheels 26, 28. The tube 18 may be fed with air by the vessel 42. The pistons may be other than spherical in shape. In a second embodiment, Fig. 2 (not shown), differs in that the working fluid is heated externally of the passageway in a heat exchanger (70) and a latch (66) replaces the wheels 26, 28. The engine may be modified to operate on the Brayton, Rankine, Otto or Diesel cycle, Figs. 3 to 5 (not shown). In another embodiment, Fig. 6 (not shown), the pistons are propelled by a travelling magnetic wave accelerator (88) to compress a gas in the passageway and induce pulses in a linear generator (90). In yet another embodiment, Fig. 7 (not shown), the pistons are again propelled by an expanding gas that is heated externally of the passageway in a heat exchanger (96) but drive a power-output shaft (100) through permanent magnets (104) fixed thereto. In a further embodiment, Fig. 8, the pistons 117 are driven clockwise along an oblongo-circular passageway 111 by expanding air that is heated in a heat exchanger 126 and enters the passageway through an inlet 123, a power-output shaft 122 being rotated by the pistons striking blades 121 extending through a slot 120. Air compressed by the pistons leaving said blades passes into the heat exchanger through a check valve 127. Blades 115 driven by a shaft 113, which may be coupled to the shaft 122, extend through a slot 116 return the pistons to the region of the inlet 123. Leakage from the slot 116 may be prevented by a housing 128. This embodiment is said to operate on a modified Brayton cycle, Fig. 10 (not shown).