Patent GB-431853-A (GB)
Abstract: 431,853. Soot blowers. BABCOCK & WILCOX, Ltd., Babcock House, Farringdon Street, London.-(Assignees of Snow, N. L. ; New Canaan, Connecticut, and Thomas, W. P. ; Highland Park, Brelsford, H. E. ; Birmingham, Howse, C. L. ; Detroit, and Bowers, F. ; Detroit, all in Michigan, both in U.S.A.) Oct. 16, 1933, No. 28631. Convention date, Dec. 27, 1932. [Class 99 (ii)] [See also Group XXVI] A blower tube 25 of a soot blower is mounted in a head 26 and is rotated by a fluid-pressure engine through gears 35, 37 on the blower tube and shaft 38 of the motor respectively, and cleaning fluid is supplied thereto by a controlling valve 90 which is located in a casing 31, bolted to the head 26 and provided with an inlet 32, and is rigidly secured to a piston 92 which is mounted for reciprocation in an extension 93 of said casing and is subjected to the pressure of a spring 94. The valve 90 is normally maintained closed by the spring 94 and also by the pressure of cleaning fluid which builds up at the back of the piston by leakage therearound, but is opened by the differential pressure on the valve and the front of the piston when the pressure on the back of the piston is released. This release is effected upon rotation of the blower tube by a cam 97 which is located on the gear 35 and opens a valve 98 on an exhaust conduit 101 leading from the casing extension 93. The engine comprises a pair of pistons 42, 43 which are mounted in cylinders 40, 41 formed in the head 26 and are connected by a yoke 44 having a slot 45 through which the shaft 38 extends, and pivotally secured to the yoke are spring-pressed pawls 46, 47 engaging a ratchet wheel 39 fixed to the gear 37 and adapted to rotate the ratchet wheel continuously in the same direction. Fluid under pressure is initially supplied to the engine from the inlet 32 through a spring- pressed valve 78 and conduit 55, and it is distributed to the cylinders by a valve 52 which comprises an elongated member with a central passage and is reciprocated in a chamber 51. When the engine starts however the cam 97 is rotated to effect opening of the valve 90 and pressure fluid is then supplied from the blower tube through a passage 81 and the conduit 55, the valve 78 being caused to close. The valve 52 is provided with an arm 61 which embraces a rod 63 carried by lugs 64 depending from the yoke 44, and springs 65, 66 are mounted on the rod 63 between the said lugs and arm to move the valve in one direction or the other when one of two levers 70, which are pivotally mounted within the head 26 and have shoulders 74, 75 to engage the arm 61, is caused to release the said arm by movement thereof effected by a pin 73 on the yoke 44. In a modification, Fig. 4, the valve 78 is opened by a spring- pressed plunger 107 which is provided with an actuating chain 87<a> and co-operates with stepped shoulders 114 on a spring-pressed slide 115 having ratchet teeth 116 which are engaged by a pawl 117 on a projecting stem 118 of the piston 92. The construction is such that the valve 78 remains open until the plunger is permitted to return to its original position by the slide 115 which is moved step-by-step out of engagement with the plunger during a predetermined number of revolutions of the blower tube. The Specification as open to inspection under Sect. 91 comprises also several modifications. In one form, Fig. 7 (Cancelled), a ratchet 154 and integral cam 151 which are loose on a shaft 153 are rotated by a pawl 156 until the cam opens a valve 146 in a conduit 145 to exhaust the space at the back of a piston 141 and permit a valve 135 in the main fluid supply pipe 126 to open. Pressure fluid then flows through a conduit 136 to operate an engine 129, whereupon the blower tube rotates and with it a cam 95<b> which opens a valve 132 leading from the main 126 to the blower tube. At the same time the cam 151 begins to rotate again by frictional engagement with the shaft 153, and when it reaches its original position the valve 146 closes; the valve 135 then closes, thus stopping the engine. Fig. 10 (Cancelled) shows a modification in which the supplies of fluid to the blower tube 25<c> and engine 129<c> are controlled by valves 132<c> and 177 actuated by cams 95<c> and 183 respectively. The cam 183 is mounted on a shaft 181 which is rotated in one direction to open the valve 177 by a chain wheel 185 and in the other direction to vided with an apertured partition 307 between which and the piston is located a spring 320. The valve is opened by pressure fluid which flows from the main 136<k> through a three-way valve 312, actuated by a handle 314, and conduits 311, 310, and is closed by the spring 320 when the pressure fluid in the cylinder 309 is exhausted through a conduit 313 upon close the valve by pawl and ratchet mechanism 191, 192 actuated by the cam 95<c>, the latter being secured to the driving wheel 176 of the blower tube. A number of such blower tubes may be operated in any desired sequence and either one or more than one at a time by securing the ends of the operating chain on the wheel 185 each to an independent sheave wheel 244, Fig. 16 (Cancelled), which is loosely mounted on a shaft 245 located near the valve 248 of the fluid main 247 supplying all the blowers and is provided with a handle 246. The cam 183, together with the associated ratchet mechanism and chainwheel, may be replaced by an electrically controlled device, the switches of each device being centralized. In another construction, Fig. 19 (Cancelled), the supply of pressure fluid to the engine is controlled by a valve 177g in the supply conduit 136<a>. The valve 177<g> is secured to a piston 260 which is located in a cylinder 261 provided with an exhaust conduit 263 normally closed by a weighted valve 266, the weight 268 of the valve 266 being raised to permit opening of said valve 266 and consequential opening of the valve 177<g> by a solenoid 270. The solenoid is actuated by a switch, and means may be provided for regulating the period of opening. Alternatively the valve 266 is dispensed with, the fluid supply conduit being provided with a solenoid-controlled weighted valve. According to a further modification, Fig. 22 (Cancelled), the supply valve 177<k> is connected to a piston 305 which is mounted in a cylinder 309 proa further actuation of the valve 312 by a collar 315 on the stem 178<k> thereof. Movement of the piston is retarded by a device comprising a needle-valve controlled conduit 317, each end of which communicates with one side of the partition 307 ; alternatively retardation is effected by escapement mechanism. This subject-matter does not appear in the Specification as accepted.