Abstract: According to the invention, a combustion apparatus includes an upright type combustion chamber having a bottom, conduit means extending below and along the bottom of the combustion chamber and having a nozzle which passes upwardly through the bottom and opens into the combustion chamber, a ringed body supported in the combustion chamber with a gap formed between the lower edge of the ringed body and the bottom of the combustion chamber, air blasted from the nozzle passing through the ringed body, a heating medium contained in the combustion chamber. Particles of the heating medium blasted by the action of the nozzle from the lower part of the ringed body are circulated through the inner bore of the ringed body.

Abstract: A conduit extends through the bottom of an upright type combustion chamber and terminates in a nozzle. A heating medium is contained in the combustion chamber and forms a naturally formed substantially conical shape having an apex. An intake port is provided at the bottom of the combustion chamber at a position corresponding to the apex of the conical shape and extends to the conduit. Particles of the heating medium which are ejected from the nozzle, via the conduit and the intake port, roll along the conical surface of the heating medium and fall into the intake port.

Abstract: In a combustion apparatus, gas for combustion is fed in a combustion chamber receiving a heating medium such as sand to continuously blow the heating medium upwardly to thereby circulate the heating medium in the combustion chamber.