Jet propulsion unit for water craft

摘要

759,630. Jet propulsion. ENDRES, J. Nov. 20, 1953 [Nov. 21, 1952], No. 32245/53. Class 114. [Also in Group XXI] An hydraulic jet-propulsion unit for water craft in which the jet is produced by a nozzle shape pumping piston or pistons each connected by a mechanical coupling element with a piston of a double-acting reciprocatory piston engine operated by gas pressure. In Fig. 1, nozzle shape pump pistons 15, 16 operating in a common pump cylinder with nozzle shape end walls 20 are connected by radial fins 19 to a piston-rod 8 and a tubular piston-rod 9 respectively of the engine pistons 1, 2. These pistons 1, .2 reciprocate in a common cylinder, forming inner and outer combustion chambers 3, 4 which have fuel injection nozzles 10. Compressor pistons 14 operating in compressor cylinders coaxial with the engine cylinder are rigidly connected to the engine pistons 1, 2 to provide compressed combustion air for the engine. When the pistons 1, 2 move outwardly under the action of the gas in chamber 3, the pump pistons 15, 16 move in wardly so that water contained in the inner pumping chamber 17 is expelled by the pistons in the form of a propelling jet,'and at the same time water entering the annular passage 22 from.the front aperture 23 passes through non- return valves 21 into outer pumping chambers 18. When the movement of the engine pistons is reversed, the pump pistons move outwardly to eject water from the outer chambers 18 and refill the inner chamber 17. Movement of the two oppositely moving piston sets is equalized by a rack and gear-wheel drive 24. In a modified unit pumping pistons are arranged both to the front and to the rear of the engine. The compressors 14 may be replaced by some other changing device. An embodiment in which compressed air flows from a reservoir into a precombustion chamber is shown.