715,640. Soot blowers. BABCOCK & WILCOX, Ltd. Feb. 11, 1953 [Feb. 11, 1962], No. 3534/52. Class 99 (2). Driving means between a fluid heater cleaner 16a and a reciprocating power device 27, e.g., a double-acting piston-cylinder device, Fig. 8, operates the cleaner during only one part of the reciprocation of the device, and driving means between a second cleaner 16b and the device operates the cleaner 16b only during another part of the reciprocation of the device, Fig. 2. There may be four pairs of cleaners disposed within a marine boiler, Fig. 1 (not shown), and operated in sequence, each pair of cleaners being associated with a power device 27. Driving means. Racks 28a, 28b connected together by a rod 30a and by a rod 30b to the piston rod 131 of the device 27 are slidable in members 100 and each rack engages a pinion 111 mounted on a shaft 110 carrying a clutch member 112 slidable on the shaft and biased by a spring 114 towards a clutch member 88 secured to a shaft 86 carrying a gear 87. The shafts 86, 110 are coaxial, and the members 88, 112 are formed with wedge-like teeth presenting complementary axially extending shoulders 91, 91a and inclined portions 92, 92a. The gear 87 meshes with a gear 50 secured to a tube 35 supported in a bracket 41 and by a gland 38 in a gooseneck 37 through which cleaning fluid, e.g., steam, passes from a valve 67 to the tube 35 and a blower element 20 entering the boiler wall 36. The tube 35 and element 20 are coupled and rotate together. Secured to the gear 50 is a cam 60 engageable with a pivoted arm 61 which operates the valve 67, Figs. 3 and 5. The members 88, 112, cam 60 and arm 61 of the cleaner 16a are of opposite "hand" compared with the corresponding parts of the cleaner 16b, Fig. 6 (not shown). Power device. A piston 130, Fig. 8, is reciprocated by a pressure fluid in a cylinder 134 and the fluid is controlled by valve means 135 comprising a spindle 137 movable longitudinally in a bore 140 of a valve body and provided with lands 138, 139 which allow the flow of fluid from a pipe 146 to outlet ports 141, 141a connected by pipes 142; 143 to the upper and lower ends of the cylinder. The spindle 137 is connected to the free end of a metal bellows 147 alternately supplied with compressed air through a pipe 148 and connected to atmosphere. There may be control valve means and rotary cam means arranged to effect automatically the operation of the several cleaners in a predetermined sequence. Rotary cam means. A disc 201 having two cam profiles 237, 238, Fig. 12 (not shown), is driven by two sets of speed-reduction wormgears, of which one set 180, 181 is shown in Fig. 11, through an electric motor. The disc is provided with diametrically opposite notches 217 in which are engaged pins 215 of the worm wheel 181 so that the disc can be disengaged from the worm wheel by drawing the disc outwardly against a spring 209 and by a handle 207. The disc can then be turned through a desired angle. Indicator strips 245 are formed on the outside of the casing 170 enclosing the disc, and a pointer 205 secured to the disc indicates which pair of cleaners are under control of the cam disc. Control valve means. Valves 226, 229, Fig. 11, are operated by the cam profiles 237, 238 which are of such a configuration that the valves 226 are closed in sequence while the valves 229 are at the same time opened in sequence. There are four pairs of valves located at equiangular spacings about the periphery of the disc 201, and the valves 229 admit compressed air through a pipe 221 to the bellows 147, while the valves 226 allow the air to be exhausted from the bellows and through a port 228. Operation. With the disc 201 rotating and considering one pair of cleaners 16a, 16b, a valve 229 is opened by the cam profile 238 and compressed air passes through the pipe 148 to the bellows 147 which moves the rod 137 downwardly to uncover the pipe 146 and thereby allow pressure fluid to flow to the lower end of the cylinder 134 to drive the piston 130 and the racks 28a, 28b upwardly. The clutch members 88, 112 of the cleaner 16b are engaged to rotate the element 20 and the cam 60 pivots the arm 61 to open the valve 67 so that cleaning fluid passes through the gooseneck 37 to the tube 20. During the upward movement of the racks the cleaner 16a remains inoperative due to the free-wheeling action of its clutch members 88, 112. After the element 20 of the cleaner 16b has turned through one or more revolutions the cam 238 allows the valve 229 to close and the cam 237 opens a valve 226 so that the air in the bellows is exhausted through the port 228. The valve rod 137 is moved upwardly by the bellows to admit pressure fluid to the upper end of the cylinder and the racks are driven downwardly so that the cleaner 16b becomes inoperative due to the free-wheeling action of its clutch members 88, 112 and the cleaner 16a becomes operative by engagement of its clutch members 88, 112 and opening of its valve 67.