Combined power device for air-breathing rocket

The invention discloses a combined power device for an air-breathing rocket. The combined power device has a double coaxial thrust chamber structure, and comprises an outer ring combustion chamber, an outer ring expansion segment, a central combustion chamber, a central expansion segment and a large exhaust pipe, wherein the outer ring combustion chamber and the outer ring expansion segment construct an outer ring thrust chamber; the central combustion chamber and the central expansion segment construct a central thrust chamber; the central thrust chamber is located in the middle; the outer ring thrust chamber has an annular structure, and is distributed circumferentially; the outer ring thrust chamber is applied to a low-altitude flight stage, adopts an air-breathing working mode, and sucks oxygen in the atmospheric air to serve as an oxidant which participates in combustion to produce thrust force; the central thrust chamber is applied to a high-altitude flight stage, adopts a rocket working mode, and uses carried liquid oxygen as an oxidant which participates in combustion to produce thrust force. The combined power device for the air-breathing rocket has the double-mode working characteristics of low-altitude height compensation and high-altitude high performance, and is a novel reusable horizontal take-off and landing single-stage-to-orbit power device for a future aircraft.