Patent GB-418294-A (GB)
Abstract: 418,294. Boiler &c. cleaning apparatus. BABCOCK & WILCOX, Ltd., Babcock House, Farringdon Street, London.-(Assignees of Brelsford, H. E.; 212, Pilgrim Road, Birming- ham, Howse, C. L. ; 3658, Mount Elliott Avenue, and Bowers, F.; 16223, Woodingham Drive, both in Detroit, all in Michigan, U.S.A.) Jan. 21, 1933, No. 2027. Convention date, Sept. 10, 1932. [Class 99 (ii).] In boiler &c. cleaning apparatus comprising a plurality of nozzled cleaner elements or blower tubes 78, 78<a> ... , Fig. 1, which are supplied with air or other cleaning fluid in puffs from a pressure tank 82 through a header 80 and branches 81, 81<a> .. and are rotated step-by-step by the pressure of the cleaning air, a device 89, Figs. 13 and 14, is provided which controls the flow of air from the tank 82 to the blower tubes in such a manner that a definite number of puffs of air is automatically supplied to each blower tube in succession. The device 89 is actuated by an electric motor 177 which is started by a manually operated switch but which is thereupon controlled independently of the starting switch by a pressure switch 88 on the tank 82 until air has been supplied to each of the blowers. As shown, the device includes a chamber 201 provided with an air inlet 101 leading from the header 80 and a number of outlets 102, 102a ... , controlled by valves 212, 212<a>...., corresponding to the numbers of cleaners, these outlets leading to mechanism for rotating the blowers. The valves 212 are arranged in spaced relation to each other on an arc and are actuated by a lever 195 which is pivotally mounted on a bracket 192 in frictional engagement with a collar 191 on a shaft 183 and is rocked by a cam 196 on said shaft 183, the shaft being coupled by gear wheels and a shaft 180 to the motor 177. Located diametrically opposite each valve 212 is a wheel 203 provided on its periphery with ratchet teeth engageable by a pawl 202 on the lever 195 and also a slot 205 to permit passage of a lug 204 on the bracket 192. In operation, and with the lever 213 above the first valve 212, the motor 84 of the compressor 83 is started and then the motor 177, whereupon the cam 196 rocks the lever 213 to open the valve 200 and permit cleaning air to pass through the line 102 to the blower 78 ; at the same time the pawl 202 advances the ratchet wheel 203 one tooth. This operation is repeated at intervals depending upon the switch 88 until the lug 204 registers with the slot 205, whereupon the bracket 192 moves with the collar 191 until the lug abuts the next ratchet wheel 203<a> and the pawl 203 engages the teeth thereof. The second blower 78<a> is then brought into operation by the valve 212<a>, and in a similar manner the remaining blowers in succession. The motor 177 is then stopped automatically by a switch between the shaft 183 and bracket 192. The number of puffs supplied to each blower is controlled by the initial position of the corresponding ratchet wheel 203, this wheel being set by an adjustable pin 207 thereon which is adapted to engage a weighted chain 209 wrapped around the shaft 208 of the wheel. The blower, Figs. 3 and 4, is preferably rotated by a pawl 108 engaging a gear 110 on the blower, the pawl being pivoted on a rod 107 connected to a piston 104 which reciprocates within a housing 103 under the action of the air pressure in the line 102 which is led to said housing, and cleaning air is supplied to the blower from the line 81 through a valve 122 which is actuated mechanically by a lever 119, the movement of this lever being controlled by a rocking lever 113 which is secured at one end to the rod 107 and is adapted to bear at its other end upon a cam 115 on the blower. The cleaning air supply valve may, if desired, be controlled pneumatically. Fig. 9, for example, shows a construction wherein the valve 158 is actuated by a piston 160 which is located within a housing 168 and moves to open the valve when the pressure at the back thereof is reduced to atmospheric by a pilot valve 148, in the pipe 102, in conjunction with the blower cam 115. In a modification of the air-supply controlling device, the air inlet 101, Fig. 18, is led through a valve 255 to a chamber 256 which is provided with the outlets 102 and locates a disc 233 having an elongated curved slot 234 which is brought into register with each of the outlets 102 in succession upon rotation of a ratchet wheel 245. The valve 255 is opened and closed to supply the air in puffs by a solenoid 249 in circuit with a thermal flasher, and the ratchet wheel is rotated by a piston which is reciprocated by air from the chamber 256 and is fitted with pawls 243, 254 engaging said wheel. The Specification, as open to inspection under Sect. 91 comprises also a cleaning apparatus for a fire-tube boiler, Fig. 2 (Cancelled), in which air is supplied in puffs to the blower tube 5 through a pipe 47, a branch 6 from the pipe 47 being provided to supply air to a housing 70 which locates a piston with integral pawl for rotating a ratchet wheel 54 coupled to the blower tube by a shaft 55. This subjectmatter does not appear in the Specification as accepted.