Patent ID: 8048176

Claim:
A reformer comprising: a reforming catalyst arranged in a cylindrical shape with a hollow interior; a burner disposed inside of the reforming catalyst, the burner having an outer surface defining a space between the reforming catalyst and the outer surface of the burner, the burner including a plurality of nozzles configured to direct flow into the space, the nozzles being disposed on the outer surface of the burner to direct flames into the space between the outer surface of the burner and the reforming catalyst and at the reforming catalyst; a combustion fuel supply valve to control a supply of a combustion fuel to the burner; a nozzle covering element variably covering portions of the nozzles and controlling a flow of the combustion fuel at each nozzle, the nozzle covering element being disposed inside the burner; and a controller to control the combustion fuel supply valve and the nozzle covering element, wherein the nozzle covering element includes a cam, the cam including: a central part to be rotated, a plurality of covering units disposed on the central part such that each covering unit is disposed adjacent to one of the nozzles, and a shaft that transmits a rotational force and that is connected to one end of the central part, wherein: each covering unit variably covers portions of the adjacent nozzle, according to the rotation of the central part, the nozzles are ovoid in cross-section, and the covering units are formed such that ends of the covering units, which contact an inner surface of the burner, have concave portions, the concave portions having a shape corresponding to the ovoid cross section of the nozzles.