Patent GB-779840-A (GB)
Title: Improvements relating to fluid heater cleaners and to fluid heater cleaner systems
Inventor: MCCOLL WILLIAM
IPC: F23J3/00
Filed: 1955-01-24
Abstract: 779,840. Soot-blowers. BABCOCK & WILCOX, Ltd. Jan. 24, 1956 [Jan. 24, 1955], No. 20.68/55. Class 99(2) In a soot-blower wherein a rotary driving means 3 is arranged through unidirectional rotation to effect projection of the blower element 1 from an inoperative position for operation, rotation of the blower element . whilst in operation, and retraction thereof to the inoperative position, the driving means 3 is arranged to rotate at a higher speed during movement of the blower element to and from the operative position than during the blowing period when the element is in operative position. The blower element 1 is similar to that described in Specifications 769,593 and 680,807 and undergoes an arcuate oscillation during the blowing period, the admission of cleaning fluid to the element being controlled by a cam member which opens a valve when the element reaches the operative position. The supply of compressed air to the motor 3 from a supply conduit 5 is controlled by two shuttle valves 11, 81 which in the retracted position of the element 1 shown in Fig. 1 are held by abutments 77, 79 in positions closing the supply conduits 73, 111, leading to the motor 3. Depression of a starting switch 133 transmits a pressure pulse through a valve 119a and passage 63 to space 22 to drive valve 11 to the right, permitting compressed air to flow from pipe 5 through pipe 73 to rotate the motor 3 which initiates movement of the element 1 to the left, whereby abutment 79 moves away from the valve 81 permitting it to be moved by air pressure to the left to permit additional compressed air to flow to motor 3 through passage 111 containing a restriction 113. The combined supply through the passages 73, 111, causes the motor 3 to rotate at high speed and move the element 1 quickly into its operative position, whereupon abutment 79 contacts the end 17 of valve 11 and moves it to the left to block the ports 51, 71, and cut off the air supply through passage 73, reducing the speed of motor so that element 1 moves slowly to the left throughout its operative period in which it is supplied with cleaning fluid and undergoes an arcuate oscillation. At the end of this period, valve 11 uncovers port 71, permitting a pressure impulse to pass through pipe 65 and valve 119b to the starting impulse line 63 of a second element 1 to initiate operation thereof, and then uncovers port 51 to renew the air supply through pipe 73 so that the speed of motor 3 is increased and the element 1 is retracted at high speed until brought to rest by the abutments 77. 79, moving the valves 11, 81, to the cut-off position. A bank of blower elements 1 may be arranged to operate in sequence, the operation of each element except the first being initiated by a pressure impulse from the line 65 of the preceding element. Each element has associated therewith a valve 119a ... g which can be set as shown at 119b to allow the pressure impulse from a line 65 to pass to line 63 to initiate the operation of the element 1 associated therewith or, as shown at 119c and 119d. to cut out one or more elements 1 and pass the pressure impulse from the second element 1 to valve 119e to initiate operation of the fifth element 1. The pressure impulse line 65 of the last blower element 1 of a series passes direct to exhaust and may be provided with a whistle to indicate termination of the operation. A similar whistle may be provided in the exhaust outlet of the last valve 119g of the series. The orifice 113 in the supply line 111 of motor 3 may be replaced by a throttle valve actuated either by a cam moving with the blower element or by. means responsive to the discharge of cleaning fluid for the element.