| 摘要 |
The burner has a radial blower with a pressure-generating chamber (31), the external walling (26) of which runs spirally. The pressure- generating chamber is essentially wider than the fan wheel (27) but, in the region of the air outlet (35), has a first blocking means in the form of a bulwark (37). The air inlet (33) to the pressure- generating chamber (31) is arranged on the periphery of this chamber and more specifically axially staggered in relation to the fan wheel (27). Between the air inlet (33) and the air outlet (35), there are second blocking means. These second blocking means (39) have a part (42) which is concentric with the fan wheel (27) and a part (43) which extends from the concentric part (42) as far as the proximity of the inner edges of the blades (41). The outlet chamber (55) has an outlet opening (57), through which combustion air can flow to the burner head. This radial blower is very compact but makes it possible to generate a relatively high pressure, as is required for burners, in which the combustion air is delivered through an air screen in order to obtain recirculation of combustion gases. By means of recirculation of the combustion gases, a relatively favourable flame temperature can be brought about, which extensively excludes the formation of nitrogen oxide. <IMAGE> |
