GB873524A - Improvements in burner registers - Google Patents

Abstract

873,524. Supplying air to burners. BABCOCK. & WILCOX Ltd. July 14, 1959 [July 14, 1958], No. 22538/58. Class 75(1). An air register comprises two sets of pivoted blades 7, 8 arranged alternately, the blades 7 of one set being pivotable in an anticlockwise direction from their closed positions and the blades 8 of the other set being pivotable in a clockwise direction from their closed positions whereby the register can be set to cause the air to be given either a clockwise or an anticlockwise rotation. Each set of blades is separately actuated by a ring 20 and 21 rotatably mounted on the front plate 1 of the register. Each blade 7 is welded to a sleeve 14 secured by screws 15 to a shaft 9 extending between the front plate 1 and the rear plate 2 of the register. Each blade 8 is welded to a sleeve 13 rotatably mounted on the shaft 9 and extending through the front plate 1 of the register. The coupling between each of the shafts 9 and the operating ring 20 for the set of blades 7 comprises two relatively movable arms 27, 28. Arm 28 is clamped by a bolt to the shaft 9 and arm 27 has a hole in which the shaft 9 fits loosely. A spring 34 is interposed between the outer ends of the arms 27, 28 and causes the other ends of the arms to grip tightly rollers 36, 37 mounted on a pin 29 projecting from the ring 20. The ring 20 is rotated by a shaft 70, a crank 74 and a link 71. When the blades 7 reach the closed position their free edges abut bars 6 extending between the front and back plates 1, 2 but further movement of the operating ring 20 is possible and causes displacement of the arms 28 relative to the arms 27 and compression of the springs 34. In this position the link 71 between the crank 74 and the ring 20 is in a slightly over-centre position. The sleeves 13, to which the other blades 8 are connected, are coupled in a similar way to the operating ring 21. The front plate 1 has an aperture 4 for a burner and the rear plate has a frusto-conical throat 3. In a modification Figs. 4, 5 (not shown) the blades are flat and are secured by springs and bolts to arms extending from rotatable sleeves coupled by forked brackets to an operating ring. In the closed positions of the blades the springs between the blades and the arms are compressed.