US2249741A - Boiler cleaner - Google Patents

Description

F. BOWERS ETAL BOILER CLEANER Filed July 19, 1937 '7 SheetS- -Shet 1 INVENTORS FRANK BOWERS BY HARRYE. BRELSFORD 4'71'" I 9 W ATTORNE July 22, 1941. F. BO-WERS ET'AL BOILER CLEANER Filed July 19, 1957 '7 Sheets-Sheet 2 N QE IIIIII IIII'IIIIIII INVENTORS FRANK BOWERS y H ARRY E .BRELSFORD 9m; v TO AT RNEg July 22, 1941. F. QBOWERS ETAL BOILER CLEANER -Filed July 19, 1937 '7 Sheets-Sheet 4 INVENTORS FRANK BO WERS zzen 2. 9; EL. iri- I mi 0%; N: o: $1 6. 09 ms wdE BRE SF RD ATTORNED% HARRY E July 22,1941. 2,249,741

F. BOWERS ErAL BOILER CLEANER Filed July 19, 1937 7 Sheets-Sheet 5 ISI FIG.9 4

INVENTORS FRANK BOWERS BY HARRY E. BRELSFORD July 22, 1941.

F. BOWERS ETAL ,249,741

BOILER CLEANER Filed July 19, 1957 7 sh ets-sheet 6 r [a] E g; 8

INVENTORS FRANK BOWERS HARRY E. BRELSFORD 7 4 ATTORNEY July 22, 1941. F. BOWERS EI'AL BOILER CLEANER Filed July 19, 193'? 7 Sheets-Sheet '7 mm. mm.

hm. v

INVENTORS FRANK BOWERS HARRY E .BRELSFORD Mafia ATTORNE Illile?! Patented July 22, 1941 BOILER CLEANER Frank Bowers, Detroit, and Harry E. Brelsford, Birmingham, Mich, I assignors to Diamond Power Specialty Corporation, Detroit, Mich., a

corporation of Michigan Application July 19, 1937, Serial No. 154,522

Claims. ({Cl. 122-392) One of the objects of this invention resides in the provision of a boiler cleaner of the character set forth having means efi'ective upon initial movement of the blower into the boiler to admit a'cleaning fluid to the blower from a source of supply and efiective upon return movement of the blower to discontinue the supply of cleaning fluid just prior to the blower assuming its inoperative position exteriorly of the boiler.

Another feature of this invention consists in the provision of means effective upon a failure in the pressure of the cleaning fluid flowing through the blower as the latter is moved into the boiler to automatically reverse the direction of travel of the blower and to return the latter to its inoperative position exteriorly of the boiler.

Still another object of the present invention resides in the provision of a boiler cleaner of the telescoping tube type embodying means within the blower nozzle supporting tubing for conducting cleaning fluid under pressure from the source of supply to the nozzle in such a manner that the packing joints associated with the outer supporting tubing will not be subjected to the maximum pressure of the cleaning fluid.

A further feature of thisinvention is to provide a boiler cleaner of the character set forth in the preceding paragraph wherein a limited amount of the cleaning fluid flowing directly to the spray nozzle from the source of supply is permitted to escape into the outer supporting tubing and wherein this fluid is circulated at a lower pressure through the outer tubing to effectively cool the latter as the blower is projected into the boiler.

An additional object of the present invention resides in the provision of a boiler cleaner embodying means for insuring eifectively cooling-the blower throughout its travel in the boiler by directing a spray of cleaning fluid against the outer surface of the spray nozzle supporting tube during the interval the latter is subjected to the heat of the combustion chamber in the boiler.

A still further advantageous feature of the present invention consists in the provision oi means for by-passing cleaning fluid into the blower prior to projecting the blower into the boiler so that normal circulation of the cleaning fluid through the blower tubing will be in effect at the time the blower is initially projected into the boiler.

A still further object of the present invention consists in the provision of means for draining the boiler wall box through which the blower extends from cleaning fluid escaping from the blower.

In addition to the foregoing, this invention contemplates a novel driving arrangement for projecting the telescoping tubes into the boiler and this construction, as well as the foregoing features and other objects, will be made more apparent as this description proceeds, especially when considered in connection with. the accompanying drawings, wherein:

Figure 1 is a semi-diagrammatic side elevational view of one type of a boiler having a boiler cleaner constructed in accordance with the present invention;

Figure 2 is a semi-diagrammatic view of a boiler cleaner installation;

Figure 3 is a longitudinal sectional view through the boiler cleaner assembly;

Figures 4, 5, and 6 are, respectively, cross sectional views taken substantially on the planes indicated by the lines 4-4, 5-5, and 6-6 of Figure 3;

Figure 7 is a cross sectional view takenv substantially on the plane indicated by the line 'i- 'i of Figure 3;

Figure 8 is a side elevational view of a portionof the control mechanism of the boiler cleaner;

Figure 9 is a plan view of the construction shown in Figure 8;

Figure 10 is'a sectional view taken substantially on the plane indicated by the line I0l0 of Figure 9;

Figure 11 is an end elevational View of the control mechanism shown in Figure 8;

Figure 12 is a sectional view through the control mechanism illustrated in Figure 8 showing the parts in a different position of adjustment; Figure 12A is a fragmentary sectional view of the magnetically controlled valve; and V Figure 13 is a longitudinal sectional View through a slightly modified form of boiler cleaner construction.

Steam boilers are usually operated at relatively high ratings and when certain types of fuel are utilized in the combustion chamber, slag is formed on the lower generating tubes of the boiler to such an extent that the gas passages between the tubes become partially or completely blocked in a relatively short period of time. As a consequence, the efficiency of the boiler is materially lower and some means must be provided to periodically remove the slag from the boiler tubes. It has been proposed to accomplish the above result by providing a projectable and retractable blowing nozzle or element which is exposed to the high temperatures within the boiler only during the blowing period when the cleaning fluid discharged through the blower performs the additional function of keeping all the exposed parts of the blower at a temperature sufficiently low to prevent any liability of damage by the heat generated in the combustion chamber of the boiler. In the interests of compactness, blowers of the above type are usually formed of a plurality of telescopically engaging tubes and it is this general type of blower that the present invention contemplates improving.

For the purpose of illustration, we have shown our improved telescopic blower in connection with a boiler of the general type diagrammatically illustrated in Figure 1 of the drawings by the reference character 2%. Briefly described, the boiler 2%! comprises a casing 2|, a cross drum 22, upper and lower decks of generating tubes 23 and 24, respectively, and a superheater 25. In accordance with conventional practice, a fire box forming a combustion chamber is located immediately below the lower deck IQ of the generating tubes, and a boiler cleaner 2! is supported on the casing 2| for movement into the latter beneath the tubing l9.

Referring now more in detail to the blower illustrated in Figures 3 to 7, inclusive, it will be noted that the reference character 30 in Figure 3 designates one side wall of a boiler having an opening 3! therein through which the blower ex- 7 tends into the boiler from the collapsed position thereof exteriorly of the boiler shown in Figure '3. In the present instance, the opening 3! through the boiler wall 30 is lined by a wall box 32 having a laterally outwardly extending annular flange 33 at the outer end abutting the exterior surface of the wall til. Positioned at the outer end of the wall box 32 is a hub 34 having an axially extending barrel portion 35 and having a laterally outwardly extending flange 36 at the inner end demountably secured to the flange 33 of the wall box by means of the fastener elements 31.

Supported by the hub 33 is a tubular casing 38 comprising a pair of axially aligned tubes 39 and 40 having the adjacent ends spaced axially from each other to receive the gear housing 4| therebetween. The inner end of the tube 39 is suitably detachably secured to the hub 34 and the outer end of this tube is demountably secured to the adjacent side of the housing 4| by the fastener elements 42. The inner end of the tube 43 is secured to the opposite side of the housing 4! by the fastener elements 43 and the outer end of this tube is secured to a header 44 by means of the fastener elements 45.

In general, the blower element comprises a plurality of telescopic tubes supported within the housing 38 for movement from the collapsed pos-itions thereof shown in Figure 3 to ane'xtended In detail, the is blower element comprises, among other parts, a nozzle 26 secured to the inner end of a tube 41 and having a plurality of circumferentially spaced openings therethrough for the discharge of cleaning fluid under pressure. The inner end of the tube 41 is slidably supported in a packing joint 48 having a packing ring 49 frictionally engaging the outer surface of the tube 41 and being welded, or otherwise permanently secured to the inner end of a tube 50. Upon reference to Figure 6, it will be noted that the tube 56 surrounds the tube 4'! and is octagonal in cross section. It will also be observed from Figure 6 that the outer end of the tube 50 is sliclably 'and rotatably. supported in the hub 34 by means of a ballbearing 5| having an inner race 52 provided with a bore therethrough corresponding in cross section to the cross sectional contour of the tube 50 in order to slidably receive the latter. The outer race 53 of the ball bearing 5| is secured in the hub 34 and rotatably supports the inner race 52 through the medium of the balls 54. With the construction as thus far described, it will be noted that both of the tubes 4 and 50 are capable of axial sliding movement and are permitted to rotate relative to the surrounding housing 38. a

The inner end of the cylindrical tube 41 is provided with an enlargement 55 shown in Figure4 as having an outer surface corresponding in cross section to the octagonal cross sectional contour of the tube 50 to slidably engage the inner surface of the latter and is internally threaded for engagement with the corresponding threads of a tube 56. The tube 56 extends axially within the tube 4! and is rotatably-su-pported on the tube 41 within the tube 56 axially beyond the inner end of the enlargement 55 by means of a ball bearing 51. The radially inner race 58 of the ball bearing is formed by the outer extremity of the tube 56 and the outer race 59 is secured to the tube 50 within the latter. It will be observed from Figure 3 that the two races are formed with registering annular grooves for receiving the balls 61).

The outer end of the tube 50 extends axially beyond the ball bearing '51 and has a nut 6| secured thereto. The nut Bl is internally threaded for'engagingcorresponding threads on the exterior surface of a tube 62 having the outer end fixedly secured to the header 44 and extending axially inwardly through the threaded tube 56. Referring again to Figure 4, it will be noted that the threaded tube 56 is prevented from rotation relative to the fixed tube 62 by forming cooperating engaging longitudinally extending flats 63 at diametrically opposite sides of the two tubes.

With the construction as thus far described and assuming that the tube 5!! is rotated in the direction of the arrow 64 by suitable power means to be presently described, it will, be noted that the nut 6| secured to the outer extremity of this tube will advance in an inward direction on the tubular fixed screw 62. Inasmuch as the enlargement 55 on the outer extremity of-the tube 'l has a sliding fit within the octagonal tube 50, it follows that the tube 41 is rotated directly from the tube 50. Owing to the fact that the cooperating engaging flats on the threaded tubes 56 and 62 prevent-rotation of the tube 55, the tube 4! is also advanced in aninward direction. It will, of course, be'understood that although the tube 50 rotates relative to the threaded tube 58, nevertheless, this latter tube must advance as a'unit with the tube '50 and, 'as a consequence, the tube 41 or spray nozzle 46 is advancedinto the boiler at a rate twice as fast as the rate of advancement of the tube 58. In other words, the spray nozzle 48 advances a distance equal to the sum ofthe housing H. In detail, it will be noted from Figure 3 that a driving sleeve 86 is rotatably supported inthe housing 39 by a pair of axially spaced ball bearings 51 supported in the housing 4| and the inner end 68 of the bore through the driving sleeve is octagonal in cross section to slidably receivethe correspondingly shaped tube 59 in the manner clearly shown in Figure 5 of the drawings. The driving sleeve is rotated by, means ofa gear 69 secured thereto between the ball bearings 6'! and adapted to mesh with a pinion 79 fixed to a stub shaft H. The stub shaft H is journalled in bearings 12 supported in the housing 4! and is coupled to the drive shaft 13 of the prime mover through the medium of the coupling l4. 7

In the present instance, the prime mover 85 is in the form of an electric motor of the reversible type for driving the tube 50 in opposite directions to -permit successively extending and collapsing the blower. Referring again to Figure 3 of the drawings, attention is called to the fact that the stresses effected by the overhanging portion of the blower as it is projected into the boiler are taken; by a tube 15 surrounding the tube 59 and engageable with the outer end portion of the same. The inner end of the tube 15 is fixed to the driving sleeve, 66 for rotation therewith as a unit, and the outer endof this tube is journalled in the header 44. As the blower approaches the limit of its extended position in the boiler, the prime mover 65 is automatically reversed and the several telescopic tubes of the blower are retracted to the collapsed position of the blower shown in Figure 3. When the blower reaches the position illustrated inFi'gure 3, the operation of the prime mover is discontinued and the parts remain in their inoperative positions until the circuit to the prime mover is again closed. The specific mechanism selected herein for the purpose of automatically controlling the operation of the prime mover to effect the above functions will be more fully hereinafter set forth.

The mechanism referred to above is shown in Figures 8 to 12, inclusive, and comprises a con-' trol unit 88 supported on the housing 39 of the blower between the prime mover 65 and the reduction gear housing 4 I The control mechanism 80 includes a limit switch 8| having two pairs of axially spaced contacts 82 and 83, respectively, electrically connected in the electric motor circuit in the manner shown in Figure 2 and having a contact bar 84 secured to an axially movable shaft 85 between the two pairs of contacts. The particular manner in which the limit switch is connected in the motor circuit shown in Figure 2 will be more fully hereinafter referred to but, for the present, it will suflice to point out that when the contact bar 84 bridges the pair of cooperating contacts 83 and the circuit to theelectrio motoris closed by the push button switch 86, the drive shaft to the motor will rotate in a forward direction to cause the blower to advance into the boiler in the manner pointed out above. On the other hand, when the contact bar 84 bridgesthe cooperating contacts 82, the polaritv of the motor 85 is changed so that the latter revolves in a reverse direction and retracts-the blower to the collapsed position thereof shown in Figure 3.

When the blower isin its retracted position, the contact bar 84 bridges the cooperating forward contacts 83 so that as soon as the operator presses the push button 86, the blower projects into the boiler. The contactibar 84 is moved in timed relation to the advancement of the blower to disconnect the cooperating contacts 83 and bridge the reverse contacts 82 when the blower assumes its extended position in the boiler. In order to move the contact bar 84 in timed relation to the advancement of the blower, a gear Bl of substantial length is secured to the drive shaft "E3 of the prime mover and this gear is shown in Figure 8 as meshing with a pair of pinions 88 and 89 which, in turn, are supported by a shaft 99. The pinion 88 is secured to the shaft 90 for rotating the latter and the pinion 89 is threadedly mounted on the shaft 90 in axial spaced relation to the pinion 88. In the present instance, a collar 9| having an annular groove 92 is secured to the pinion 89 and the latter has one less tooth than the gear 81 and the pinion 88. As a consequence, rotation of the 'drive shaft in the direction of the arrow 92 causes thepinion 89 and collar 9| to move axially of the shaft 90 in the direction of the pinion 88.

Movement of the collar 9| in an axial direction toward the pinion 88 effects a corresponding sliding movement of a rod 93 through the medium of a shifter link 94 having one end secured to the rod and having the other end extending into the groove 92 of the collar. The rod 93 is slidably supported in the casing of the control mechanism and is shown in Figure 9 as having a lost motion connection with a shifter rod 95 supported for sliding movement in a direction parallel to the direction of sliding movement of the rod 93. The lost motion connection referred to comprises a link 98 having one end secured to the rod 93 for axial adjustment and having the free end slidably receiving the rod 95' between the axially spaced abutments 91 and 98 on the rod 95. The abutment 9'! is fixed to the rod 95, while the abutment 98 is adjustable to provide for varying the-movement of the rod 95 by the rod 93. In any event, the location of the adjustable abutment 98 isso determined that when the movable contact bar 84 of the limit switch bridges the forward contacts 33 or, in other words, when the blower is in its retracted position, the free end of the link 96 engages the abutment 98.

It follows from the above that as the blower is advanced into the boiler, the link 96 i advanced by the rod 93 relative to the rod 95 and the location of the abutment 91 on the latter rod is so determined that just prior to movement of the blower to its extreme projected position, the link 96 engages the abutment 91 and moves the rod a distancedepending upon the axial distance between the two. pairs of cooperating contacts 82 and 83. Referring again to Figure 9, it will be noted that the rod 95 is operatively connected to the shaft 85 of the limit switch so that movement of the rod 95 by the link 98 the distance previously referred to causes the switch contact bar 84 to disconnect the forward contacts 83 and bridge the reverse contacts 82. v

The operative connection between the limit switch, shaft 85 and the rod 95 comprises a pair of links 99 and I99 secured to the shaft 95 at opposite ends of the limit switch. The free ends of the links 99 are apertured to slidablyreceive the extremities of the switch shaft 85 and adjustable abutments II)! are secured to the switch shaft 85 axially beyond the free'ends of the links 99 and I99. As a consequence, when the link 96 engages the abutment 9? to move the rod 95 in a direction toward the reverse contacts 82, the free end of the link I99 engages the adjacent abutment I9! on the switch shaft 85-and slides the latter shaft the distance required to bridge the reverse contacts 92 by the contact bar 84. This causes a change in the polarity of the electric motor 65 and effects rotation of the drive shaft I3 in the reverse direction to retract the blower from the boiler.

Inasmuch as the drive shaft I3 is rotating in a reverse direction, it follows that the pinion 99 is moved by the gear 9? away from the pinion 88 or in a direction toward its initial starting posi tion shown in Figure 8. Movement of the pinion 89 in the above direction effects movement of the bar 93 in a corresponding direction relative to the shaft 95 until the free end of the link 98 again engages the abutment 98 whereupon the shaft 95 is moved in the same direction. Movement of the shaft 95 by engagement of the link 96 with the abutment 98 causes the link 99 to cooperate with the adjacent abutment I9I on the switch shaft 85 to return the contact bar 84 to its'initial position wherein it bridges the forward contacts 83. Incidentally, it may be pointed out that move- :ment of the contact member 84 from aposition wherein this contact member bridges the reverse contacts 92 to a position wherein the same bridges the forward contacts 33 opens the'circuit to the motor 65 and requires manipulation of the push button 86 to effect another-operating cycle.

In the event it is desired to indicate to the operator the position of the blower relativeto the boiler throughout the entire-cycle or operation, suitable indicating means maybe installed upon the control unit shown in Figures 8 and 9. As will be observed from these figures, an ini 'dicator plate I92 is secured to the outer side of the casing for the control mechanism-and a needle I93 is operatively connected to the drive shaft for swinging movement over the 'indicating plate. needle I93i's secured to the outer end of a shaft I94 journalled in the casing and havinga crank arm I95 fixed to the inner end thereof. The free end of the crank arm has a follower I 96 secured thereto and this follower engages in the groove 92 l of the collar 9I on the pinion 89 for actuation-by the latter. Inasmuch as the pinion 89 reciprocates in timed relation to the'blower, it follows that'the needle I03 will indicate the location of the blower at any point in its operating cycle.

'In a manner to be more fully hereinafter set forth, a cleaning fluid under pressure-is discharged into the outer end of the tube 62 through the header 44 in timed relation to movement of the blower into the boiler and, in the present instance, this cleaning fluid is caused to flow directly from the header to the nozzle without subjecting the several packing joints between the cooperating telescopic tubes tothe maximum pressure'of the cleaning fluid. This is accomplished herein by providing two telescopically engaging tubes I91 and I99 within the blower. Upon reference to Figure 3, it will be noted that the smaller tube I01 is secured at its inner end to the nozzle 49 and the outer tube-I98 is s'lidably' sup- In the present "instance, "the ported at its inner end on the tube I01 through the medium of a packing joint I09. The outer tube I08 also supports the free end of the tube 56 through the packing gland III] and, in adddition, has a sliding fit within the inner end of the tube 52. "The arrangement is such that both tubes communicate directly with the source ofrcleaning fluid under pressure admitted to the outer end of the tube 62 through the header 44 and the tube lIl'I moves as a unit with the spray nozzle 46. The relative length of the two tubes is such as to provide a continuous conduit for the flow of cleaning fluid from the header 44 to the nozzle in the extreme extended position of the blower. It follows from the above that the cleaning fluid flows directly from the tube 62 to the spray nozzle 46 without subjecting the packing glands to the relatively high pressure thereof and, as a consequence, more effective spraying of the boiler tubes with the cleaning fluid is accomplished.

It is desired, however, to effect a circulation of cleaning fluid under a relatively lower pressure through the telescopic tubing of the blower in order to maintain the outer tubes relatively cool when projected into the boiler. This is accomplished in the present instance by forming outlet openings II I in the inner end of the pressure tube lu'l permitting cleaning fluid to escape into the interior of the tube 41. The cleaning fluid thus discharged into thetube 41 flows in a direction toward the outer ends of the tubes between the tubes 47 and 55. As shown in Figure 3, suitable openings II2 are formed through the tube 41 adjacent the enlargement 55 on the outer end'therecf and the fluid passes through these openings into the tube 50, whereupon the fluid returns to the inner end of the blower and is discharged out of the blower against the projecting tube 41 through a relatively small passage II3 formed in the packing joint 48 in such a manner as to by-pass the packing ring 49. 'Thus, a circulation of the cleaning fluid is provided in the blower tubes and a jet of cleaning fluid under the circulating pressure is constantly discharged against the projecting tube during the blowing operation.

It will, of course, be understood that there will be a leakage of cleaning fluid through the ports II 4 and II 5 formed in the outer ends of the tubes '59 and I5 respectively. .Any fluid leaking through these ports is permitted to escape through the drain conduit II9 communicating with the interior of the casing 39. Also, any fluid escaping by the packing joint I I1 between the driving sleeve 65 and the tube 50 is permitted to drain through the conduit II8 which also communicates with the interior of the casing 39. Any fluid leaking from the blower into the wall box 48 is permitted to drain out of the wall box through a conduit II9 communicating with the 'lower side of the wall box in the manner clearly shown in'Figure 3.

Upon reference to Figure 2, it will be noted that the conduits H6, H9, and H9 communicate with a common drain I20 through the'medium of a conduit I2I. The outer .end of the conduit I2I and the blower end of the conduit H6 communicate with a cleaningfluid supply conduit I22 through the medium of a three-way valve I23. The supply conduit I22, in turn, communicates with a source of cleaning fluid under pressure I24 thr'ough'the medium of a stop valve I25 and a main shut-off valve I29. The arrangement is suchas to permit the blower to be initially filled with cleaning fluid prior to projecting the blower into the boiler, and this is accomplished by opening both of the valves I26 and I and by manipulating the three-way valve I23 to establish communication between the conduit H6 and the supply line I22, and to close communication between the conduit H6 and drain conduit I2I. When the valves are in the above named position of adjustment, cleaning fluid flows through the conduit H6 into the casing 39 and fills the blower tubes to the level of the outlet conduit I21. As shown in Figure '7, the outlet conduit I21 extends laterally outwardly from one side of the blower casing 39 and discharges into the funnel I28 which, in turn, communicates with the drain conduit I2 I. Referring again to Figure 2, it will be noted that the funnel also collects any leakage of cleaning fluid in the housing M and this is accomplished by establishing communication between the bottom of the housing 4| and the funnel through the medium of a conduit I29.

-- 'It has previously been stated that the clean- Wall 39 of the boiler to' prevent spraying this wall with the cleaning fluid and for the same reason the flow of cleaning fluid is discontinued as the blower approaches the wall 30 on its return movement. As shown inFigure' 2, the source of supp-1y I24 communicates with the header 44 atthe outer end of the blower through the medium of a conduit I3I! anda valve I3I is located in this conduit normally closingcommunication therethrough. The valve is shown in Figure 12 as comprising an apertured valve seat I32 arranged to require the cleaning fluid from the source to flow through the aperture I32 in order to reach the 'header I44. The opening I32 is normally closed by a valve member I33 having a valve stem I34 slidably supported at its upper end in the valve casing I35. The lower end of the valve stem is slidably supported in the casing by meansof a piston I36 secured tothe stem I34 and mounted for reciprocation in a cylinder I31 surrounding the valve stem. The valve member I33 is maintained in its closed position with respect to the opening I32 by means ofa coil spring I38 surrounding the stern I34 with one end engaging the piston and with the other end engaging a fixed abutment secured to the valve casing. It will beobserved from Figure 12 that the design of the valve I3I is such that the bottom side ofthe piston I is subjected to the pressure of the cleaning fluid from the source and, inthe present instance, the spring I38 is not of sufilcient strength to maintain the valve member I33 seated against the action of the cleaning fluid pressure. However, communication is establishedbetween the high pressure side of the system and the portion of'the cylinder I31 above the piston and, for accomplishing this communication, a passage I39 is formed through the valve stem I34. As a result, the upper side of the piston is'also subjected to the' action of the cleaning fluid under pressure and, consequently, the valve member I33 is normally maintained in its closed position.

The valve member I33 is lifted from its seat upon initial movement of the blower into the boiler by efiecting a drop in pressure of the fluid in the cylinder I31 above the piston I36and this is controlled by means of a slide valve I49. As shown in Figure 12, the slide valve I40 communicates with thecylinder I31 above the piston I36 through the medium of a conduit MI and also communicates with the drain conduit I2I through the medium of a conduit I42. The general arrangement is such that when the blower is advanced into the boiler, communication is established between the portion of the cylinder I31 above the piston I36 in the valve I3I and the drain opening to effect a sufficie'nt're'duction in the pressure above the piston I35 to cause the pressure of the cleaning fluid from the source to move the piston I35 against the action of the spring I 38 and thereby open the valve member I33 to permit cleaning fluid to flow into the blower. In detail, the slide valve I40 for effecting this operation comprises a plunger I44 slidably supported in the casing of the'valve I49 between the conduits MI and I42. The plunger I44 is provided with an axially extending recess I communicating with the drain conduit I42 and having radially extending ports I43 therethrough' adapted to register with correspondingports I41 in the innermost position of the plunger to establish communication between the conduits MI and I42. The plunger is normally urged to aposition wherein communica tion is established between the valve cylinder I31 and the drain conduit I42 by means of a spring I48 located in the valve casing with one end engaging the outer end of the plunger and with the other end abutting theadjacent end of the casing.

Although the spring I 48 normally urges the valveplunger I44 in'a position wherein the valve I3I is open, nevertheless, in the retracted position of the blower, the valve plunger I44 is held against the action of the spring I48 in a position wherein the ports I45 and I41 are out of registration. and wherein the valve I 3I is, accordingly, closed. Uponreference to Figure 12, it will be noted that the valve plunger is held in itsclosed position against the action of the spring I48 by means of an adjustable abutment I50 secured to the outerend of the rod 93 beyond the link 96. The location of the abutment I50 on the rod 93 issuch that when/the blower is in its retracted position, the abutment engages the forwardly projecting end I 5| of the valve plunger and positively holds the latter inits inoperative position against the action of the spring I 48 wherein the plunger closes com munication between the valve I3I and the drain conduit I2I. It follows, therefore; that when the blower is in its retracted position shownin Figure 3, communication between the source of cleaning fluid supply I 24 and the blower is closed by the valve I3I. However, as theblower is projected into the. boiler in the manner previously set forth, the rod 93 is moved in an inward direction and disengages the abutment I50 from the'projecting end I5I of the valve plunger permitting the springl48 to move the valve plunger toits operative position wherein communication is established between the valve I3I and the drain conduit I2I. As a result of movement of the valve to this position, the pressure in the portion ,of the cylinder I31 above the piston I33 of the. valve I3I is substantially lowered and the pressure of the cleaning fluid from the source of supply raises the valve. member I33 from its seat to open the aperture I 32. This permits the cleaning fluid to flow through the aperture I32 to the outer end of the blower through the header 44. By the time the cleaning fluid under pressure reaches the spray nozzle 45 at the inner end of the blower, the nozzle is projected a sufficient distance into the boiler to prevent the cleaning fluid from contacting with the inner surface of the side wall 30 of the boiler.

It will, of course, be understood from the foregoing that when the blower is retracted by reversing the prime mover 65, the abutment I58 at the outer end of the slide rod 93 re-engages the outer projecting end II of the plunger M4 and movesthis plunger to its inoperative position against the spring I 48. In other words, as the plunger assumes its position of rest shown in Figure 3, the cleaning fluid under pressure from the supply line is permitted to build up in the cylinder I31 in the valve I3I above the-piston I36 and, as soon as this pressure approaches the pressure of the cleaning fluid'at the source of supply, the springl38 returns the valve member I33 -to its closed position wherein communication is discontinued from the source of supply to the blower. 7

With the above construction, it will be seen that the blower forming the subject matter of this invention is not only provided with means for automatically retracting the blower when the latter assumes its extended position in the boiler, but is also equipped with means effective upon initial movement of the blower into the boiler to automatically supply cleaning fluid under pressure to the blower, and effective as the blower approaches its retracted position to automatically discontinue the supply of cleaning fluid to the blower.

Inasmuch as the commercial success of the blower depends to a great extent upon maintaining the several parts thereof at a sufficiently low temperature to avoid damage, means is provided for automatically retracting the blower from the boiler in the event that there-is a failure in the pressure of the cleaning fluid. The above is accomplished by automatically actuating the limit switch BI to bridge the reverse contacts 82 with the contact member 84 in dependence upon a drop in pressure of the cleaning fluid passing through the blower. Upon reference to Figure 10, it will be noted that the bridging contact member 84 is normally yieldably urged toward the cooperating reverse contacts 82 by means of a coil spring I53 surrounding a rod I54 mounted for sliding movement parallel to the movement of the rod 55 and having a sliding connection at one end with the link 96. As shown in Figure 10, one end of the spring I53 engages a fixed abutment I55 surrounding the rod I54 and the other end of the spring is adapted to engage'a link I56 extending between the rods 94 and I54. One end of the link IE3 is secured to the rod '95 and the other end of the link slidably receives the rods I54. The construction is such that the spring I53 acts through the link I53 tending to move the rod 95 in an inward direction to effeet a corresponding movement of the contact member 84 into engagement with the reverse contacts 82. However, in the retracted position of the blower, the spring I53 is prevented from moving the switch due to the fact that therod 95 is held from inward movement by engagement of the abutment 98 on this rod with the link 96 on the rod 93. The rod 93 cannot move axially relative to its driving connection with the blower and, accordingly, the spring IE3 is preventedv rod I54.

rod P13.

frcm disturbing the position of the contact'mem- 'ber 84 with reference tothe'forward cooperating contacts 83.

It will, of course, be understood that some means must be provided for normally maintaining the spring I53 inoperative to actuate the limit switch 8| during normal operation and to permit the link 96 to move axiallyrelative to the rod 95. This'is accomplished in the present instanceby providing'a piston I69 supported in a cylinder NH and having an outwardly extending plunger 62 located in axial alignment with the The portion of the cylinder at the inner side of the'piston IE3 communicates with the source ofcleaning fluid under pressure beyond the Valve I3I by'means of the conduit I63 so that as soon as the valve I isactuated by the abutment I53 on the rod 93 to open thevalve 'I-3I, the piston I moves outwardly in the cylinder IBI asufiicient distance to engage the outer end of the plunger 162 with the adjacent inner end of the rod I65. In eifect, therefore, the piston'lfiflforms' an abutment for-the spring I53 to provide'normal operation of the limit switch by the rod 95 through its connection with the shift However, if for any reason the flow of cleaning fluid to the blower is interrupted, the pressure at the inner end of the piston ISO is immediately reduced and the spring I53 snaps the limit switch to a position wherein the reverse contacts are bridged by the member 84.

As hereinbefore stated, this effects a reverse rotaticnof the drive shaft I3 and causes the blower to retract from the boiler.

From the circuit diagram shown in Figure 2 of thedrawings, it will be noted that the circuit to theprime mover may be manually opened. at any time by operating'the push button switch I65 which is normally closed. Also, the forward rotation of the drive shaft "I3 by the prime mover '65 may be reversed at any time during the projecting movement of the blower by closing the push button switch I65. In addition, it will be noted from the circuit diagram shown in Figure -2 that there are two sets of magnetically operated switches designated by the reference characters I51 and 168. Assuming that the line switch I69 is closed and that the forward contacts 83 are bridged by the contact member 8 1, it will be noted that the circuit to the prime mover may be closed by merely pressing the push button switch 83 to close the same. Closing of the switch 85 energizes the coil I I0 of the electromagnet HI and the armature of this magnet moves the several switches in the set I67 to their closed positions in a manner not shown herein. When the switches in the set I61 are closed, the prime mover 65 is connected to the source of power and rotates the drive shaft 13 in a direction to projectthe blower'into the boiler. It may be pointed out at this time that-the switch I72 of theset F5? is shunted across thepush button switch 86 so that when the latter is released by the operator,the circuit to the prime mover remains closed. Attention is also directed to the factthat the stop switch I65 is-in series with the switch I12 so that when this stop switch is opened, the electromagnet III is de-energized and the circuit to theprimemover is broken.

When the reverse contacts 82 are bridged by the contact member 83, the coil I13 of the electromagnet IN is energized causing the armature of this electromagnet to open the set of switches I61 and close theset-ofswitches I68.v Thishas the effect of reversingthepolarity ofthe prime moverv 65 and causing the latter to drive the shaft 13 in a reverse direction to withdraw the blower from the boiler. The stop switch I65 is also in series with the circuit to the electromagnet I14 so that when this stop switch is opened, the circuit to the prime mover is also opened and the power is discontinued.

It has previously been stated that provision is made herein for reversing the prime mover to retract the blower at any time during its projecting movement by closing the push button switch I68. In this connection, it will be noted that there is provided an electromagnetically controlled valve I15 controlling communication from the pressure end of the cylinder [6i to the drain conduit l2l. This valve is normally maintained closed by a suitable spring ll! and is opened against the action of the spring by the electromagnet I16 which, together with the push button switchlfifi, is located in the circuit I18. As a consequence, closing of the push button switch I66 completes the circuit to the electromagnet and opens the valve I11 against the action of the spring to relieve the pressure in the cylinder IE1 at the end of the piston I69. As hereinbefore stated, this allows the rodl l to movein an inward direction under the action of the spring I53 and thereby actuate the limit switch 8! to engage the cooperating reverse contacts 82 by the bridging member 84. Of course, bridging the reverse contacts 82 reverses the polarity of the prime mover 65 and effects a retracting movement of the blower.

For the purpose of manually retracting the blower in the event that the prime mover 65 should fail, there is preferably provided a sheave wheel I80 secured to the drive shaft 13. A chain l8| is engaged with the sheave wheel and this chain is accessible from the floor of the blower room so that the same may be readily manipulated by the operator.

Referring now more in detail to the modified form of blower illustrated in Figure 13, it will be noted that this blower .diifers principally from the one previously described in that the spray nozzle 46' is not rotatable and in that the'inner threaded tube 62' is rotated by, the reduction gearing instead of being fixed in the .header l l' at the outer end of the blower. 'In detail, the outer end of the tube 62 is rotatably' supported on the inner end of a tubular bushing I82 having the outer end supported on'the header M'f and having a seal I83 surrounding the same to prevent leakage of the cleaning'fluid under pressure admitted to the tube 62 through the header;

The tube 62 is driven by a gear I84 secured to the outer end of the tube 62 adjacent the header and meshing with a pinion I85 keyed, or otherwise suitably secured, to the drive shaft 13 of the prime mover 65. Also,rin-this construction, the outer end of the tube extends beyond the nut El and is secured to abushing I86 having a sliding fit with the inner cylindrical surface of the blower casing I81. I g

It will be observed from the above that rotation of the tube 62' causes the nut El and associated tube 15' to move axially inwardly. As in the first described formpf the invention, the tube 15' is octagonal in cross section to fit the correspondingly shaped outerv end portion of the tube 41' and, inasmuch as theportion 55 is threaded on-the revoluble tube 56, it follows that the tube 47f will also be moved outwardly. As a matter of fact, this arrangement is the same as described in the first form of the invention and causes the spray nozzle 46' to movea distance equal to the sum of the threadedleads on the tubes 56 and 62. With the noted exceptions described above, the blower illustrated in Figure 13 operates in the same manner as the blower unit described in connection with Figures 1 to 12, inclusive.

- While in describing the present invention, particular stress has been placed upon numerous details of construction, nevertheless, it should be understood that the advantageous results may be secured by substituting various other arrangements and, accordingly, reservation is made to make such changes in the construction as may come within the purview of the accompanying claims.

What we claim as our invention is:

- 1. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, means for moving said blower element to said positions, means for initiating the actuation of said moving means, means for thereafter controlling and continuing the operation of said moving means to cause the same to move the blower element from its retracted to its projected position and to then automatically return the blower element to its retracted position, a

source of cleaning fluid under pressure communieating with the blower element, valve means controlling communication from the source to said blower element, and means effective upon predetermined movement of the blower element to its projected position to open the valve means and eifective as the blower element approaches its retracted position to close the valve means.

2. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions,'means for moving said blower element to said positions, means for initiating the actuation of said moving means, means for thereafter controlling and continuing the operation of said moving means to cause the same to move the blower element from its retracted to its projected position and to then automatically return the blower element to its retracted position, a source of cleaning fluid under pressure communicating with the blower element, and means responsive to a substantial drop in the pressure of the cleaning fluid admitted to the blower element as the latter is moved toward its projected position to automatically actuate the controlling means to cause the blower element to return to its retracted position.

3. In a fluid heater cleaner, a blower element mounted'for movement to projected and retracted positions, means for moving said blower element to said positions, means for initiating the actuation of said moving means, means for thereafter controlling and continuing the operation of said moving means to cause the same to move the blower element from its retracted to its projected position and to then automatically .return the blower element to its retracted position, a source of cleaning fluid under pressure communicating with the blower element, and means responsive to a substantial drop in pressure of the cleaning fluid admitted to the blower element as the latter is moved toward its projected position to' discontinue further movement of said element toward its projected position and immediatelycause said element to return to its retracted position.

' i, In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, a power device for alternately moving said blower element to said positions, control means for said power device, means actuated in synchronism with the blower element for operating the control means to cause the latter to effect a reversal of the power device after a predeterminedprojection of the blower element, a source of fluid under pressure communicating with the blower element, and means responsiveto a substantial drop in pressure of the cleaning fluid at any point in the travel of the blower element toward its projected position to effect a reversal of the powerdevice and thereby cause the blower element to return to its retracted position.

5. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, power driven means connected to the blower element for movingthe same to said-positions, control means for the power driven means operating to reverse the actuation of the power driven means after the blower element has been projected a predetermined amount, a source of cleaning fluid under pressure communicating "with the blower element, means efiective upon a substantial drop in pressure of the cleaning fluid to automatically operate the control means to cause the power driven means to reverse and retract the blower element, and means under the control of the operator for efiectinga sufficient drop in pressure of the cleaning fluid at any point in the travel of the blower element to its projected position to reverse the power driven means through the control means and retract the blower element.

6. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, power driven means for alternately moving the blower element to said positions, control means for said power driven means, means actuated in synchronism with said blower element for operating the control means to cause the latter to effect a reversal of the power driven means after a predetermined projection of the blower element, and means under the control of the operator for actuating the control means to reverse the power driven means at any point along the path of travel of the blower element 'trol means to cause the latter to eifect a reversal of the power driven means after a predetermined projection of the blower element, a source of cleaning fluid under pressure communicating with the blower element, means under the control of the operator for effecting a substantial dropin pressure of the cleaning fluid, and means responsive to a drop in pressure of the cleaning fluid to operate the control means to reverse the power driven means at any point along its path of travel to the projected position thereof.

8. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, power driven means for alternately moving said blower element to said positions, control means for said power driven means, means actuated in synchronism with the blower element for operating said control means to cause the latter to effect a reversal of the power driven means after a predetermined projection of the blower element, a source of cleaning fluid under pressure "communicating with the blower element, valve means controlling communication from the sourceto said element, means effective upon predetermined movement of the blower element toward its projected position to open said valve and effective as the blower element assumes its retracted position to close said valve, means responsive to a substantial drop in pressure of the cleaning fluid to operate the control means to cause the latter to effect a reversal of the power driven means at any pointin the travel of the blower element to its projected position, and means under the control of the operator to effect the drop in pressure of the cleaning fluid required to operate said last named means and cause the blower element to be returned to its retracted position. 7

9. In'a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, power driven means for alternately moving said blower element to said positions, control means for saidpower driven means, means actuated in synchronism with said blower element for operating the control means to cause the latter to efiect a reversal of the power driven means after a predetermined projection of the blower element, yieldable means normally urging the control means to a position wherein the latter effects a reversal of the power driven means. a source of cleaning fluid under pressure communicating with the blower element, and means responsive to the pressure of the cleaning fluid for rendering said yieldable means inoperative.

10. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, power driven means for alternately moving said blower element to said positions, control means for said power driven means, means actuated in synchronism with said blower element for operating the control means to cause the latter to effect a reversal of the power driven means after a predetermined projection of the blower element, yieldable means normally urging the control means to a position wherein the latter effects a reversal of the power driven means, a'source of cleaning fluid under pressure communicating with the blower element, and means responsive to the pressure of the cleaning fluid for rendering said yieldable means inoperative, said last named means being operative upon a substantial drop in the pressure of the cleaning fluid to permit the yieldable means to actuate the control means to-cause the latter to efiect a reversal of said power driven means. I

11. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, power driven means for alternately moving said blower element to said positions, control means for said power driven means, means actuated in timed relation to movement of said blower element for operating thecontrol for effecting the drop in pressure required to render the last named means inoperative and thereby permit the yieldable means to actuate the control means to efiect a reversal of the power driven means.

12. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, means for moving the blower element to said positions, a source of cleaning fluid under pressure communicating with the blower 13. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, means for moving the blower element to said positions, a source of cleaning fluid under pressure communicating with the blower element, means controlling communication between said blower element and source of cleaning fluid under pressure including a valve having a casing provided with a valve seat through which the cleaning fluid under pressure is adapted to flow to the blower element and having a valve member engageable with said seat to close communication from the source of cleaning fluid to the blower element, said valve, member having a portion arranged with the opposite sides subjected to the pressure of the cleaning fluid O at the source, means supplementing the action of the cleaning fluid at one side of said valve portion to maintain the valve member against its seat, said last named means exerting a force less than the pressure of the cleaning fluid, and means responsive to movement of the blower element toward its projected position to efiect a drop in pressure on the side of the valve portion subjected to the action of the closing means whereby the pressure on the opposite side of said valve portion moves the valve member away from its seat and permits cleaning fluid to flow to said blower element.

14. In a fluid heater cleaner, a blower element tween said blower element and source of clean-' ing fluid under pressure including a valve having a casing provided with a valve seat through which the cleaning fluid under pressure is adapted to flow to the blower element and having a valve member engageable with said seat to close communication fromthe source of cleaning fluid to the blower element, said valve member having a portion arranged with the opposite sides subjected to the pressure'of the cleaning fluid at the source, means supplementing the action of the cleaning fluid at one side of said valve portion to maintain the valve member against its seat, said last named means exerting a force less than the pressure of the cleaning fluid, and a second valve establishing communication between the atmosphere and casing at the side of the valve portion influenced by the closing means, said second valve being responsive to movement of the blower element toward its projected position to open the line of communication from the first valve casing to the atmosphere and thereby effect a drop in pressure at the side of the valve portion subjected to the action of the closing means and permit the pressure at the opposite side of the valve member to move said member to its open position, said second valve also being responsive to movement of the blower element to its retracted position to close the line of communication from the first valve casing to the atmosphere and thereby permit said valve closing means to close the first valve.

15. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, means for moving the blower element to said positions, a source of cleaning fluid under pressure communicating with the blower element, means controlling communication be-- tween said blower element and source of cleaning fluid under pressure including a valve provided with a valve member having the opposite sides subjected to the action of the cleaning fluid under pressure, means acting on one of said sides of the valve member for normally urging said valve member to its closed position, said last named means exerting a force on the valve member less than the pressure of the cleaning fluid, and a second valve responsive to movement of the blower element toward its projected position to effect a drop in pressure on the side of the first valve member subjected to the action of the closing means to permit the fluidpressure acting on the opposite side of said valve member to open the first valve.

' FRANK BOWERS.

HARRY E. BRELSFORD.

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