US1562634A - Controlling and operating means for engines, for underfeed stokers, and the like - Google Patents

Description

D. F. GRAHAME AND OPERATING MEANS FOR ENGINES, FOR UNDERFEED Nov. 24, 1925.

CONTROLLING STOKERS, AND THE LIKE Filed July 1, 1922 5 Sheets-Sheet 1 NNN NNRN Now 24 \1925.

5 Sheets-Sheet 5 Y J2 M6711???" ZQZZQSZ6 TQ7Z ZM3 D. F. GRAHAME CONTROLLING AND OPERATING MEANS FOR ENGINES, FOR UNDERFEED STOKERS, AND THE LIKE Filed July 1. 1922 fl0a, 4 M%%Q Nov; 24, 1925. 1,562,634

F. GRAHAME D. CONTROLLINGVAND OPERATING arms FOR ENGINES, FOR UNDERFEED STOKERS,'AND THE LIKE Filed July 1. 1922 5 Sheets-Sheet 4.

Nov. 24, 92 1,562,634

D. F. GRAHAME 'comnouuue AND OPERATING mums FOR ENGINES, FOR UNDERFEED STOKERS, AND THE LIKE Fil d J l 1922 5 Sheets-Sheet 5 A 72 z /e72f071' Patented Nov. 24, 19925.

UNITED STATES 1,562,634 PATENT OFFICE.

' DALLAS F. GRAHAME, OF TORONTO, ONTARIO, CANADA. ASSIGNOR, BY MESNE ASSIGN- MENTS, TO RILEY STOKER CORPORATION, OF WORCESTER, MASSACHUSETTS, A

PORATION OF MASSACHUSETTS.

CONTROLLING AND OPERATING Application filed July 1,

To all whom it may concern:

Be it known that I, DALLAS F. GRAHAME, a subject of the KingofGreat Britain, and a resident of Toronto, in the Province of Ontario, in the Dominion of Canada, have invented certain new and useful Improvements in Controlling and Operating Means for Engines, for Underfeed Stoker-s, and the like ef which the following is a specification.

My invention provides advantageous means for operating, and for controlling the operation of, a plurality of engines that are actuated by fluid pressure from a common source; and in some of its aspects it is more particularly intended to improve the flexibility of operation and of control of stoker ram-driving mechanisnfio-f the general character set forth in my co-pending application Serial No. 545,044, filed March 28, 1922.

One of the objects of my present invention is to provide for a plurality ofengines arranged to be operated from a common source of fluid pressure supply, such as a liquid pump, means for controlling the operation of each engine so that each individual engine may be cut out of operation without preventing the functioning of any other. enthe cut-out valve; Fig. 6 is a top-planyiew gine of the series, and/or each individual engine may be made to work in its own selectively-determined periodicity, but with the engines always working one at a time.

Another object of my invention is to provide advantageous valving means operatable under pro er control'to out out of service or as I wil term it for brevity) disable that engine with which it is connected.

i battery of engines for A further object of my invention is to pro vide simple, effective and easily adjustable means, individual to each engine, by which the 0 erator'may selectively set the enginedisab ing means (such as the valvingmeans referred to) for desired periodicity of operation.

Another object of my invention is to provide hydraulic actuating mechanism for a r'iving Stoker-rams or the like. which will be simple, inexpensive, easily installed and maintained, eflicient and .giving desired flexibility in the operation of the respective engines.

Other and further objects of my invention on the broken section line 33 of Fig. 4; Fig. 4 is a transverse section of said mechaparts as seen from below Fig. 9.

COR-

MEANS FOR ENGINES, FOR UNDERFEED STOKERS, I

AND THE LIKE.

1922. Serial No. 572,240.

will become apparent to those skilled in the art from the following description taken in conjunction with the accompanying drawings in which I have shown the application of my invention as applied to Stoker-driving mechanism and wherein, for purposes of dis} closure, 1 have mainly illustrated the same in diagrammatic fashion; and it will be understood that the specific structural embodiment shown and the arrangement which I illustrate may be widely varied, and that the controlled engine may be utilized for various kinds of work, within the spirit of my invention and in the scope of the appended claims.

In the drawings, Fig. 1 is a diagrammatic representation of the application of my invention to a stoker-drive; Fig. 2 is a detail diagram of a valve operating means shown in Fig. 1;. Fig. 3 is a section of an engine cut-out valve, with parts in elevation, taken nism taken on line 44 of Fig. 3; Fig. 4* is a detail of the controlling valve; Fig. 5 is a front elevation with parts broken away of a step-by-step operating mechanism for of Fig. 5; Figs. 7, 8 and 9 are views similar different wo'gking positions; and Fi "10 is an inverted plan viewef Fig.9 showing the 86 A, battery of engines is diagrammatically illustrated as com rising only three, although any suitabl number may be provided. Engines 20, 20 and 20", I call, for convenient identification, the first, intermediate and last engine, and while I shall describe parts with particular reference to the first engine 20, in most instances, similar parts of other engines are indicated by like numerals ofreference distinguished by the exponents a and b.

Engine 20 comprises cylinder 21 and pi'ston 22, the latter having its'piston rod connected to astoker ram or plunger R' for the boiler 13, all pistons being shown in home position, so to term theposition at their instroke end where they rest between feedingoperations. For 0 erating the en 'nes, a fluid, preferably oi will be suppli under requisite pressure from a pump 23 driven by an electric motor or other suitable prime mover 23, the pump being connected to draw on reservoir 24 and,-through the pipe 25 and pressure-alternating valve 26', to supply the liquid under pressure alternately to the two feed pipes 27 and 28 that respectively lead to the first engine and the last engine. At substantially all times valve 26 connects one feed pipe to the pressure pipe 25 from the pump, while connecting the other feed pipe to the return duct 24' of the reservoir 24. Reversing valve 26 is suitably operated to stand in the position shown in Fig. 1 long enoi'igh to enable the pressure supply through feedpipe 27 to drive all engine pistons of the battery 011 their outstrokes, and upon reversal of the valve or movement to opposite extreme of position in its cylinder it.' will then supply pressure to the feed pipe 28 for an equal length of time. Valve 26 is thus merely one simple means of alternating the pressure application or direction of fluid flow between the feed pipes that lead to the opposite extreme engines, and its frequency of operation may be varied as by means hereafter described directly to affect the frequency of operation of all of the engines.

he engines have interconnections be tween their cylinders arranging them in series or succession, these connections being so disposed that the piston of each engine may act as a controlling valve for the engine or engines posterior to it in the then existing direction of pressure flow through the piping. Thus, in the diagrammatic illustration of Fig. 1, pipe 27 which is receiving pressure from pump 23 has open connection with a passage 29 leading directly into the inner end of the cylinder of engine 20, While, through passages to be described, the outer end of that cylinder has open communication with the return pipe 28. As piston 22,

driven by the pressure approaches its outgine 20 just beyond the home position of the stroke position it passes the port for pipe .30 which is connected to the passage 29? for the next or intermediate engine, conditioning that engine to effect its piston out-stroke, in

turn to open pipe 30 for the next engine of the series. Of course when the last engine has effected its piston out-stroke, all engines remain idle in the stated condition pending reversal of the valve 26. The further connections between the engines whichserve as return flow passages on the above stated outstrokes of the plstons will, after their reversing valve has moved, direct the reverse p pressure through the engines seria'tim from left to right or 'in reverse order, While the heretofore described. passages 29,. 30, etc, will, under these reverse conditions, act as thereturn'passages. Engine cylinder 21' normally has-its outer end connected bya passage 31 andpipe 32. with a port of en- In the general organization thus far described, my present system accords with that set forth in my pending patent application aforesaid.

Further, where the invention is used in hydraulically driving stoker rams, the control over the reversing valve 26 may be exercised by means substantially asset forth in said application, and in the present drawings the steam pressure in boiler B may govern a regulator R for a rheostat 1' that governs the speed of an electric motor M for the stoker blast fan F, from the shaft of which is driven the mechanism that reverses valve 26. Through vbelting and pulleys P the gears G are driven, one of them carrying. a suitable cam mechanism 0 to act on the stem 26 of the hollow valve 26 to reciprocate it. As boiler pressure rises fan speed is out down, and withit the frequency of reciprocation of valve 26 and the feeding capacity of the ram battery as a whole, As boiler pressure drops both air and fuel supplies will be augmented.

To attain one of the objects of my present invention I provide in connection with each engine a valve arrangement 35 by which that engine may be put out of service or disabled, so that its piston will remain in home position when, pressure is being supplied to the engine battery through the supply pipe 27, this disabling of the selected engine being so .accognplished that it does not interfere with the operation of any other engine in the bat tery. And for selective operation of each which communicates with passage 29, and a passage 39 which leads through the cylinder wall ust beyond the home position of the piston. When pressure, from feed pipe 27' raises this valve, the piston in its home position is bypassed; pressures on opposite sides of the piston are substantially balanced, and the piston will not make an outstroke. With the. specific arrangement of piping connections between the cylinders that has been above described,and which I prefer to employ, it is necessary that the .normally open connection between passage 31 and pipe 32 be closed, while liquid is flowing through the by-pass valve aforesaid, in order to insure that the pressure thus bypassed around the one piston shall be exerted through the pipe 30 to actuate the next engine in the series (if such next engine be otherwise set for normal operation). In order to accomplish the cutting off of communication between pipes 31 and 32*, a second valve-element or head 40 is connected to and movable with the stem of by-pass valve 37 This valve-element 40 may be one head of a spool-shaped valve-and-piston structure, as shown in Figs. 3 and 4 and when such structure moves to the position shown in Fig. 3 the part 40 closes the ports for the two passages 32 and 39. In the normal position of the valving parts (shown in Fig. 4)

the passages 32 and 39 communicate with each other through the valve-channel 41 in tervening between valve-head 40 and the piston-head, 42, of said valve-and-piston structure. This piston head 42 works in a cylinder 43 in which a light spring 44 may be provided to aid in normally maintaining the valve 37 closed.

The cut-off valve structure may be operated in various ways. but I prefer to provide that structure, as shown, in the form of a pressure-actuated valve governed by a rotatable pressure-relief valve, which in turn is actuated by the selective mechanism 36 which thus effectively controls the periodicity of operation of the cut-off valve structure.

The piston head 42 exposed to cylinder 43.

is preferably largerthan the area of valve 37 exposed to passage 38, so that as long as pressure from passage 38 is freely applied to both the under side of the valve and the top of the piston, the valve will remain closed. Controlling valve 46 establishes such ,a pressure connection during the major portion of its rotative cycle. It

has a peripheral groove 49 throughout the major portion of its circumference which will connect the port 50 from cylinder 43 with a passage 51 leading through the valve shell to passage 38. At one position in its rotation, however, valve 46 cuts 011' the normally open connection through passage 51 tothe passage 38 and connects port 50 with a relief passage 52 that opens past backcheck valve 52 into the passage 39 above Longitudinal duct 54 in the ro- .tatable valve effects such relief connection,

valve 37.

as shown in Figs. 3 and 4. The valve 46 is rotated step-by-step by the selective mechanism, with the cut-off valve structure re?" maining ineffective as long as channel 49 is open to port 50, but when the valve is stepped to the position shown in Figs. v3 and 4 the next succeeding pressure impulse communicated from the pump through pipe 27 will raise the cut-off valve structure from the position shown in Fig. 4 to that shown thus (except for the omission or plugging of useless ports) the physical structure above described may remain unchanged for uniformity of equipment.

The selective controlling mechanism for rotating the valve "46 may be considerably varied, but in the preferred mechanism shown I make all selectors alike and op,- erate them all by respective links '58 from .28, no valve element 40 need be provided,

crank arms59 on a rock shaft 60 which is reciprocated, in unison, with reciprocations of reversing valve 26. by a piston 61 arrangedin a cylinder 62 that has its opposite end piped as at 27' and 28 to the respective feed pipes 27' and 28, the piston rod having a crank connection 63 to rock shaft-60. Each link 58 operates its corresponding pawl carrier 65 loosely mounted .on the valve stem 66 (Fig. 4), the main pawl 67 on one end of said carrier coacting with the main ratchet wheel 68 that is fastened to the valve shaft 66. The pawl reaches laterally from position for engagement with the ratchetteeth 69 across the plane of a shield segment 70, which is loosely adjustable coaxially with shaft 66 to vary. the number of teeth that may be engaged the pawl for 'elfectuating a movement 0 the ratchet wheel, and thereby to vary the length of throw of the ratchet wheel and the valve effected by each reciprocation of the pawl carrier. This shield has a projecting arm 71 that may be latched by a pin 72 in any .one of the indexing apertures 73 on frame plate 74, Fig. 5 showing the shield set to permit full stroke operation of the pawl; Fig. 7 showing the setting for I shortest or singletooth throw of the pawl;

Fig, 8 showing-an intermediate position and Fig. '9 showing theshield plate permanently lifting the pawl as may be desirable to hold one engine] permanently disabled.

It is desirable thatprovision be made so that; whatever may be the effective to0thprogression accomplished by each stroke of the pawl carrier "under the variable settings provided for, the rotatable valve 46 shall always, at one stage of the rotation thereof, be brought accurately to position registering its passage 54 with the port 50 for relief of pressure in valve cylinder 43,

and .on the next stroke of the pawl carrier shall fully remove. the passage 54 from such communication. To this end a secondary pawl 76 is mounted on the opposite end of carrier 65 to cooperate with a secondary ratchet wheel 77 that has only two notches 78 and 7 8, so spaced that when the leading one of said notches is engaged the secondary pawl 76 at full retraction, and moved forward a full stroke, it accurately positions the valve in relief station, and posi vtions the following; notch 78 to receive the secondary pawl 76 at the end of the next retraction, so thaton the next operating stroke of the pawl carrying arm the valve may be carried fully out of relief position. It is manifestly desirable, in this connection, to leave smooth or toothless such are of the primary ratchet wheel as will make 'the .movement of the valve finally into and fully away from relief position wholly dependent on the secondary pawl. Also. it is desirable to connect with the projecting or setting arm 71 some appropriate means, such as pin 80, to throw the secondary pawl positively out of range for engaging notch 78 when the indexing arm is set in zero position as shown in Fig. 9 to permit a permanent disabling of its afl'ected engine. This pin 80 may therefore act on a lip 81 on the pawl. Since also it may be desirable'on occasion to rotate the valve manually, instead of automatically, a turning handle 83 may be provided on the extreme end of the valve shaft 66. I v

In rsum of the operation: The boiler pressure 'afl'ects the regulator R to modify the speed of the prime mover Mfor fan F to vary the supply of air to the underfeed.

.a frequency dependent upon the boiler pressure, although the periodicity of.operation of each engine relativelyto the periodicity of operation of other engines in the battery may be varied or any one or more engines may be cut out of service without disabling the others. From the fan shaft is driven the gearing G that reciprocates the reversing valve 26 by which, alternately, the working pressure of pump 23 is turned into the feed pipe 27 or into the feed pipe 28, the remaining one of said pipes being connected at the return pipe to the reservoir 24. As the reversing valve 26 is. reciprocated, so 1s the piston 61 reciprocated to rock the shaft which actuates the'step-by-step selective mechanisms for the respective cut-ofl' .valve structures 35 of the several engines of the battery. With none of said valve structures 35 in disabling position, pressure from plpe 27, communicated through passage 29 w1ll drive from home position the p1ston of the first engine until it opens the connection 30 whichcommunicates with the inner end of the cylinder for the second engine, and so on throughout the series, the fluid ahead of each engine piston being driven through the return passage from cylinder to cylinder via the connections 31, 32, etc., all of which will be open under. the conditions stated. Accordantly the en ines make, in sequential order, their respective outstrokes, the minimum frequency of movement of valve 26 being enough to enable this to be accomplished before a valve reversal takes place. When the valve reverses the direction of pressure flow through the series connected cylinders is reversed and all engines (but in reverse order) make their instrok'e or piston returns to home position. With each reciprocation of the piston 61 (concurrent with reversals of the valve 26) the rotary control valve 46 for each engine has imparted to it a rotative step of such len th as is determined by the setting of the se ective mechanism 36 appurtenant to that valve. During most of the rotation of each valve its long channel 49 keeps the pressure passage 38 in communication, through passage 51 and port 50, with the cylinder 43 of the pressure-controlled cut-off valve. Piston 42 being of larger effective diameter than valve 37, said valve 37 will remain constantly closed under this condition. Finally, chamber 43 is relieved when valve 46 reaches the position shown in Fig. 3, by the opening of the valved connections 50, 54, 52 to the upper side of the by-pass valve 37. Consequently on the next occurrence of a pressure impulse through pipe 27 valve '37 will be forced 0 en, and will carry up with it the non-inter erence valve 40 to close off the normally opened connection between passage 31 and pipe 32. Assuming it is engine 20 whose valve has thus opened to bypassing position, it will be seen that pressure from feed pipe 27 may flow through the 0 en valve 37 and passage 39 into the cylin erv beyond the home position of the piston 32, leaving that engine inert, or in other words, disabling its piston temporarily. The pressure application proceeds through pi e 30 to thenext engine of the series, whic may thereupon operate to take its out-stroke, and so on throughout the rest of the battery. The pressure thus released into cylinder 21 through the connection 39 cannot find escape through the return pipe 28 via the passage 31 for the reason that said passage is' cut-ofl' by the non-interference valve 40. Inorder permanently to cut any engine out of service it is only necessary to turn the indexing handle 71 to zero posltion as shown in Fig. 9, wholly disabling the ratchet and pawl mechanism, and manually to bring the rotary controlling valve 46 to the position shown in Flg. 4 by turnin the handle '83 to the upright position in icated in Figs. 7 and 9.

While I have herein described in considerable detail a specific embodiment of my invention it will be understood thatin its broader aspects I do not desire to be limited to the details shown (except as some refinements are claimed for their specific advan tage), and that many changes iii construction, arrangement and operation of various parts may be made without departure from the spirit of my invention within the scope of the appended claims.

I claim: 1. In combination, a plurality of engines to be operated, means for supplying pressure alternating in direction to said engines,

connections between said engines to transfer pressure from one to another thereof normally to provide for their operation in successlon, and means associated with one of said engines to render said engine inoperable by said alternating pressure Without disabling any other of said engines.

2. The combination of a plurality of engines, means for supplying actuating pressure alternately to the opposite extreme ones of said engines, pressure-transfer connec tions between sald engines for pressure transfer from one to the other normallyto operate saidenginesin predetermined succession, and means associated with each said engine respectively, operable to by-pass the pressure with respect to said engine without disabling any other engine.

3. The combination of a plurality of reeiprocatory engines, interconnections between the several engines of the series for pressure transfer from one to another, a liquid pump, connections including a reversing 'valve for connecting said pump alternately with the extreme engines of the series, and means for cutting out of operation any engine of the series.

4. In combination, a plurality of engines to be operated by an alternatingly directed fluid pressure, connections between said engines to transfer pressure from one to another thereof td operate them normally in succession, means associated'with' each said engine operatable to render said engines non-responsive to the stated pressure, and se- 'lective timing mechanism for automatically operating the last said means.

5. In combination, a plurality of engines, means for supply liquid pressure alternately in opposite directions to the extreme ones of said engines pressure transfer connections between sai engines in series to normally condition each engine for pressure response as the result of piston movement of its predecessor in the series, and-means associated with each engine for iby-passing pressure arbund its piston. I

6. In combination, a plurality of engines gines, series connected for single successive then in opposite order on their in-stroke,

and means for by-passing pressure around one of said engines when its piston is'in instroke position.

8. The combination with a plurality of engines normally connected in series for successive operation of their pistons by pressure supplied to the extreme engine, and means for bypassing the pressure around anyengine of the series.

9. The combination with a plurality of enoperation in response to pressure alternately supplied to opposite ends of the extreme ones of said engines, and means connected with each engine of the series for by-passing pressure around its piston without disabling any other engine of the series, and means for operating any said by-passing means at will.

. 10. The combination with a plurality of engines, series connected for single successive operation in response to pressure alternately supplied to opposite endsof the extreme ones of said engines, and means connected with each engine of the. series for by-passing pressure around its piston without disabling any other engine of the series, and means for automatically actuating each by-passing means after a selectively determined number of im ulses of pressure.

11. The combinatlon'with a plurality of engines, series connected for single succesnately supplied to opposite ends of the extreme. ones of said engines, and means connected with each engine of the series for by-passing pressure around its piston without disabling any other engine of the series, and means for automatically actuating each by-passing means after a number of pressure lmpulses selectively determined for that 120 individual engine.

12. In combination, a plurality of engines to be operatedby pressure supplied alternately inopposite dlrections to opposite ex-. treme ones of said engines, pressure transfer connections between said engines in series for their normal operation in predetermined succession, cut-oft valve means associated with one of said engines for by-passing the j pressure around the piston'for saideng ne, and variablys'ettable means for condltionmg sive operation in respdnse to pressure alter- I connections between the engines for presend of the first engine to iust beyond the insure transfer from one to another in series, including, between the first and second engine, and so on throughout the series, normally open connections from the out-stroke stroke position of the piston for the next engine and from the inner end of the second engine to a point just inwardly from the out-stroke position of the cylinder of the first engine, a by-pass connection for the first engine, and a valve, normally closing said by-pass', arranged when open to close the connection from the outer end of said first engine cylinder to, the second engine cylinder. 14. The'combination of a plurality of'engines each having a cylinder and piston, means for alternately supplying fluid under pressure to the inner end of the first engine and the outer end of the last engine, normally open series connections between said engines including a power-flow connection and a return flow connection, and means associated with the first said cylinder for bypassing pressure around its piston to the power flow connection of the next cylinder, said means including a valve movable to close the return flow connection from the first engine to the-second as the by-passing connection for the first engine is opened.

15. The combination with a plurality of engines, hydraulic actuating means connected therewith normally in series thereby to operate said engines in predetermined sequence, and hydraulically actuated valve means for cutting out of operation any selected engine of the series.

16. The combination with a plurality of engines, hydraulic pressure actuating means therefonarranged normally to operate said englnes 1n predetermined sequence, and hydraulically actuated valve means for cutting out of operation any selected engine'of the series without disablin the remaining eng1nes, said valve means includinga valvegovernlng mechanism and automatic means for periodicall operating said mechanism.

17. The com ination with a plurality of engines, hydraulic pressure actuating means therefor arranged normally to operate said engines in predetermined sequence, and hydraulically actuated valve means for cutting out of operation any selected engine of the series w1thout disabling the remaining engines, said valve means including a valvegoverning mechanism and automatic means or periodically operating said mechanism, includ ng ratchet and pawl mechanisms.

18; The combination with a plurality of engines whereof the extreme ones have feed pipe connections to their opposite ends, hydraulic pressure supply means for supplying pressure alternately to said feed pipes, pressure transferring interconnections be tween said engines normally to operate them in sequence on their out-strokes and in reverse sequence on their in-strokes, valve means connected with each engine for rendering it individually non-responsive to pressure application tending to move it on its out-stroke, said means including a valve for by-passing pressure around the piston of said engine.

19. The combination with a plurality of engines whereof the extreme ones have feedpipe connections to their opposite ends, hy-

draulic pressure-supply means forisupplying pressure alternately to said feed-pipes, pressure-transferring interconnections be tween said engines normally to operate them in sequence on their outstrokes and in reverse sequence on their in-strokes; valve-means connected with each engine for rendering it individually non-responsive to pressure a plication tending to move it on its out-stro e and including a valve for by-passing pressure around the piston of said engine, said by-pass valve being itself ada ted to be pressure-operated; and a rotatab e valve for controlling the application or release of pressure to saidtby-passing valve for operation of the latter.

20. The combination with a pluralityof.

engines whereof the extreme ones have feedpipe connections to their opposi ends, hydraulic pressure-supply means for supplying pressure alternately to said feed-pipes, pressure-transferring interconnections between said engines normally to operate them in sequence on their out-strokes, and in reverse sequence on their .in-strokes; valve-H means connected with each engine for rendering it individually" non-responsive to pressure application tending to move' it on its out-stroke and including a valve for bypassing pressure around the piston of said engine, said by-pass valve being itself adapted to be pressure-operated; a rotatable valve for controlling the application or'release of pressure to said by-passing valve for oporation of the latter, and means for autodering it individually non-responsive to pressure application tending to move it on its out-stroke and including a valve for bypassing pressure aroundthe piston of said engine, said by-pass valve being its elf adapted to be pressure-operated; a rotatable valve for controlling the application or release of pressure to said by-passing valve for operation of the latter, and means for automatically operating said rotary valve including a ratchet and pawl mechanism comprising means settable to vary the steplength thereof and means operatable regardless of such step-length to bring said rotary valve invariably to proper relief position and in a single stroke to move it fully out of relief position.

22. In an underfeed stoker drive, the combination with the boiler, fuel feeding rams and reciprocatory engines for said sure and operatively connected to a part of said hydraulic system automatically to vary the periodicity of operation of said reversing valve, and means for operating said step-by-step mechanism, accordantly with the operations of said reversing valve.

DALLAS F. GRAHAME.

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