GB356892A - Improvements in gas heating systems - Google Patents

Abstract

356,892. Gas burners; pilot-jets. KEITH & BLACKMAN CO., Ltd., J. and KEITH, G., 27, Farringdon Avenue, London. July 31, 1930, No. 23073. [Classes 75 (i) and 75 (iii).] In a gas-heating system for bakers' ovens and the like, sets of burners, preferably a central burner 75 and a ring of burners 74, are surrounded by a tube 89 extending within a combustion chamber 99 connected by heat radiating tubes 101 to a header 100, leading to a fan 98 for removing the products of combustion and fitted with a valve 102 for varying the draught to regulate the flow of gas and air to the burners. The gas may be supplied mixed with insufficient air to form an explosive mixture. As shown, the burner 75 is provided with a central gas supply tube 78 in an air supply tube 77 communicating through inlets 79 with the atmosphere. The burners 74 are provided with gas supply tubes 84 extending from a chamber 72 and a common air chamber 73 communicating through tubes 83 with air inlets 81 in a rotatable cover-plate 82. The tube 78 and chamber 72 are connected respectively by pipes 61, 62 with a governor 12 loaded to atmospheric pressure, the pipes 61, 62 being provided with stop-cocks 65, 66 and obturators 67, 68. The cock 65 is connected by a link 92 to the plate 82 so that the gas and air supplies to the burners 74 may be cut off simultaneously and independently of the burner 75. The tubes 78, 84 are centred by means of perforated plates 85 and may be provided with caps 86 having inclined perforations 87. Part of the air is supplied to the flames through apertures 91 around the burners. The flame of a pilot-burner 97 is adapted to be drawn by the suction of the fan through one of the air inlets 79 for lighting the burner 75 which in turn ignites the burners 74. In a modification, the air is supplied to the burners by means of a fan, a branch pipe being connected to the governor so as to maintain the gas pressure equal to the air pressure. The governor may also be loaded to a variable subatmospheric pressure by the method described in Specification 270,786, [Class 75 (i), Burners &c.]. Specification 348,767 is also referred to in the Provisional Specification.