GB658619A - Improvements in or relating to fuel oil burners - Google Patents

Abstract

658,619. Liquid-fuel burners. LANGHAM, A. J. July 2, 1948, No. 17864. [Class 75(i)] [Also in Group XII] I n a n oil-fuel burner having a burner nozzle and a number of circumferentially spaced air deflector blades annularly supported around a draught tube mouth each blade has an inwardly directed outer portion and a laterally directed inner portion and is inclined to the draught tube axis to divide the air passing therethrough into a number of sub-streams so as to create a peripheral series of high and low pressure pockets and to produce auxiliary eccentric swirls in the main air-oil vortex. The apparatus has an air duct 1, to which air is supplied by a fan 7 and controlled by a valve 9, an oil spray nozzle 14 mounted on a longitudinally adjustable cross bar 10 and a venturi shaped throat ring 21 around the internal circumference of which are mounted in slots 31 a number of deflector blades 26. The deflector blades 26, formed with an outer portion 27 and a laterally extending inner portion 28 are inclined to the tube 1 axis so that air flowing therethrough is thrown outwardly by portion 28 and deflected laterally by portion 27 to impart a forwardly travelling spiral or swirling movement to the air so that an air vortex made up of a number of spirally swirling air streams impinge upon and cut the oil spray issuing from nozzle 14. The inner portion 28 of blade 26, joined to portion 27 at an angle of approximately 130 degrees with a sharp corner as shown, or curved Fig. 16 (not shown), is bent in the,direction in which the air is deflected by portion 27 and lies tangential to an imaginary cone concentric with ring 21. The edges 55 and/ or 56 of all or some blades may be serrated, notched or crimped. The blades 26 may be secured to the ring 21 by lugs and screws 45, 46 as shown in Fig. 2 or as shown in Fig. 10 by crimping or rivetting 48 at the bottom of a recess 47. A streamlined bush 49, slidably mounted on the nozzle stem 13, is provided to enable the cross-sectional area of the annular air space formed 'between it and the ring 21 to be varied. In alternative constructions .Figs. 23 and 25 a slidable bush 51 or 51' provided with air deflector blades 53 or 53' attached to its periphery, imparts a rotational swirl to the air passing through the control region of tube 1 in the same direction as that imparted to the air in the outer region by the blades 26. The air duct is provided with a cover 17 which carries a sight glass 18 and a pair of ignition electrodes 19, .20.