GASEOUS FUEL BURNER

摘要

1380567 Dual flow-rate burners ROBERTSHAW CONTROLS CO 14 Dec 1971 [15 Dec 1970] 58031/71 Heading F4T A burner comprises a housing having a first chamber 88 and a second chamber 96 communicating with chamber 88 via an aperture 90 of small cross-section relative to that of main gas outlet ports 84 from chamber 88, the chamber 96 having gas outlet ports 92 and the housing having a single inlet 82 only for fuel gas whereby at a normal fuel flow rate gas issues from both ports 84 and 92 to form flame patterns as shown in Fig. 6 while at a lower flow rate little gas issues from ports 92 and the flames at ports 84 have a pattern as shown in Fig. 5. At the lower flow rate the flames from ports 84 pass through openings 112 in a flame spreader 110, having wind-guard tabs 113, to heat a thermocouple T which is heated by flame from ports 92 at the normal fuel flow rate. Chamber 96 has air inlet holes 98 and forms a mixing chamber for fuel gas passing from aperture 90 to ports 92. In a modified burner, Figs. 10-14 (not shown), the main flame at the normal flow rate is above a flame spreader and impinges on an annular surface (322) thereon to give better control of the normal flow rate flame characteristics. The burner 78 has a normal/low fuel flow rate ratio of at least 5/1 and is connected by a thermocouple cable C and a single gas conduit to a control device of the type forming the subject matter of Specification 1,380,568.