US2369692A - Steam jet pump - Google Patents

Description

Feb. I20, 1945.

.w.' l-l.A TINKER STEAM -JET PUMP l 5 Sheets-Sheet l .Filed Aug. 21, 1942 Fel.y zo,Y 1945.

W.k H. TINKER STEAM JET PUMP Filed Aug. 21, 1942 3 Sheets-Sheet 2 Feb. 2o, 1945.

Filed Aug. 2l, 1942 3 Sheets-Sheet 3 reame Feb. 20.1945

y UNITED STATE-s. PATENT oFFicE STEAM JET PUMP' Walter 1I. Tinker, Boston, Mass., assignor to Manning, Maxwell & Moore, Incorporated, New York, N. Y., a corporation of New Jersey Application August' 21, 1942, serial No. 455,553

1i claims. (ci. 10a-zio)A This inventionpertains to steam jet pumps of the type commonly known as injectors and wherein a portion ofthe heat energy of steam is directly converted into mechanical energy for the purpose, for example, of forcing feed water into a boileragainst a pressure which may be as greatI or greater than that of the steam supplying the Jet and the residue of such heat is returned directly to the. boiler.

While of broader utility and application, the invention is herein described and illustrated by way bf example with-reference to its embodiments in an injector of the axial-now type. Preferably, although not necessarily, it is intended to be arranged in accordance with usual locomotive practice at a level below the level of the feed water supply so'that under normalconinjector inlet.

A primary object of rthe invention is to provide an injectorI of automaticrestarting type which isalsosatisfactory in respect to its ability to deliver hot feed Water against pressures encountered in practice.

In the operation of an injector of this type there must be a free communication/with theA water supply when the injector is started, and after the injector has come into full operation and is delivering water to the boiler against the boiler pressure, it is desirable to control the rate at which the water is so delivered. For practical reasons, it is diiiicult to control this ratev of delivery merely by varying the amount of steam supplied, and-it is generally desirable and common practice to continue the steam supply at maximum ilow through the operation of the instrument, after starting,l and to vary 4the rate of delivery of water to the ,boiler by governing,

the amount of water which enters the injector. Heretofore, this has commonly been done by prowith feed water as hot as 135 F; and which is of simple,'dur able and'inexpensive construction.

It is a known fact that an injector will start more rapidly whenv the steam is first admitted and caused to entrain the Water from the sup- -ply rather than when the steam is admittedto iiooded injector chambers. When the steam leads the water, the rst water which enters the combining tube combines quickly with the steam,

condensing the latter and starting the effective injector action, such action oftentaking place under such circumstances so quickly that there is no waste of water at all through the overow. This relation of events prevents prema- 'tlre development of liquid pressure in the delivery chamber which might close the-overilow valve too soon, that is prior to establishment of dltions water under'some head is present in the admission valve, and i"n which the movement of l viding the 4water supply pipe with a valve independent of that which controls the admission of steam, thus permitting the .water valve to be opened more or less without necessarily disturbing the setting of the steam-admission valve.

. In its more general aspects a further object of the invention is to provide an injector capable of delivering against a boiler pressure of the order of 300 pounds per square inch for example; which has a single controlhandle for starting, regulating and stopping it; which will automatically restart ify it breaks during operation due to lack of or excessively hot feed water; which start s withoutexcessive waste otwater-Awhich may be ter, are among the most the delivery jet.

Accordingly, it is a more specic object of the present invention to provide practical and simple means whereby, in an injector of this type, the steam leads the water when the apparatus is started and wherein the admission of water may readily and accurately be controlled without de- I,

creasing the amount of steam belowthat required to deliver the water admitted through the watervof steam, condensate and feed water will not be greatly impeded, thus permitting progressive building up of velocity until energy sufficient has been developed to force the feed water past the check valve into the boiler. While the continued operation of the apparatus, after the jet is once established, is not dependent upon the closing depended upon to start and operate effectively 55 of this usual overflow, it has been found that if this overilow remainl open during operation, there is a tendency for the jet to draw in air, dust. and cinders, which are delivered with the water into the boiler. For these reasons, among others. it has been common to provide the overliow with a valve designed to be closed after the jet has been main overflow chamber fofilthe injector.

established and also to be closed while the injector is idle. However, if this be a manually operated valve, skill and careful attention on the 'part of the operator are necessary for its proper actuation and furthermore, if the injector breaks during operation, the flow will not be reestablished until the operator has manually opened this overflow valve.

Commonly the tube assembly is furnished with a plurality of spaced spillway passages all leading into an overflow chamber of limited capacity. During establishment of the delivery jet, the several spillways successively come into action so as to vent the advancing stream of fluid and thereby prevent undue decrease in velocity. After the jet has been established, these spillways continue to have functional value, the later spillways of the series, in particular, permitting a sort of breathing action during which fluid may move outwardly through some and inwardly through others. However, the entrance end of the tube assembly is where the greatest difficulty is encountered in establishing the jet and it is here that the stream of mixture is at all times most sensitive to variations in pressure conditions. Thus, at this entrance end, sufficient spillway area must be provided during starting to insure free escape of the steam delivered by the entraining nozzle, together with some at least of the entrained water, thereby 'to insure the requi- I site high velocity for the proper entrainment of the water. On the other hand, too large an area of spillway at this early stage is not conducive to good continued operation, particularly if this early spillway be subject to the variable pressure conditions which subsist during operation in the overflow chamber into which the later spillways ever, so far as Iam aware,"it has not previously been recognized that greatly improved results with respect to initial establishment of flow and particularly automatic restarting after breaking may be obtained by making the flrst spillway of large capacity and providing a conduit leading from saidiirst spillway directly to the outer'atmosphere or other space wherein pressure conditions are substantially constant, said first spillway being of such capacity as to disi charge substantially all of the steam delivered by the regulating nozzle together with the Water entrained thereby, but with the proviso that said auxiliary spillway be closed (preferably automatically) when the injector is idle and when it is in full operation but be open directly to which the other spillways deliver, and with further pr-ovisio-n for automatically closing this initial spillway as soon as the jet has been established. Y

A further object of the invention is to devise an injector of this general type having provision whereby the quick starting of the injector is as-J sured and its continued operation made certain even under adverse conditions, but without requiring the provision of auxiliary manually operated valves or other devices for controlling the overflow.

A further object is to provide an injector of this type which will start and automatically restart more easily and certainly than previous injectors; which will deliver against a high pressure head; which is of simple and durable construction; and which embodies an automatic overflow valve which functionsv not only to close the usual overflow conduit of the injector when the latter is idle Qr in full operation, but which also controls an auxiliary overflow conduit leading from the first spillway located at a point near the entrance throat of the combining tube and which does not communicate with the usual overflow chamber.

Other and further objects and advantages of the invention will be pointed out hereinafter and lby reference to the accompanying drawings,

wherein Fig. 1 is a vertical section illustrating one embodiment of the present invention;

Fig. la is a fragmentary horizontal section substantially on the line I--I of Fig. 1;

Fig. 2 is a longitudinal section (to larger scale and horizontally disposed) in a plane at right angles-to that of Fig. l, illustrating the nozzle assembly and omitting other parts;

Fig. 3 is a section, to larger scale, on the lin 3-3 of Fig. 2; l

Fig. 4 is a section, to larger scale, on the line 4 4 of Fig. 2; I

Fig. 5` is a section, to larger scale, on the line 5-5 of'Fig. 2;

Fig. 6 is a fragmentary section similar to Fig. 1, but illustrating a modification; Fig. '7 is a section similar to Fig. l but illustrating another and preferred embodiment of the invention; and

Fig. 8 is a fragmentary section, to larger scale than Fig. 8, showing details of the steam-admission valve and adjacent parts.

Referring to Figs. 1 to 5 of the drawings, the numeral I indicates the casing of the injector. This casing as here shown (Fig. 1) is a unitary casting so devised and with the operative parts so relatively arranged and located as to permit all necessary machine work to be done easily and inexpensively. This casing has a projecting screw-threaded nipple 2 to which the steam supply pipe may be connected, the steam which is supplied through the pipe entering an inlet chamber 3'within the casing. The casing also has a projecting screw-threaded nipple 4 to which the feed water hose is connected, a feed water check valve 5 being arranged at the entrance to the water inlet chamber 6.

The casing has a transverse septum 'I provided with an aperture dened by an annular valve seat 8 with which cooperates the wateradmission valve 9. This valve 9 has an actuating stem I0 which passes out through a stuffing box I I carried by a removable cap I2 coaxial with the valve stem I0 and which is screw threaded into an aperture in the casing wall. Preferably, the stem I0 is so connectedY to the valve 9 as to permit the valve to seat withoutl cramping .and also to allow la slight axial movement (for ex- :,aoacea ample oi' the order of Vlot an inch) between ternally screw-threaded body portion I6, of the forcerv nozzle I1, said forcer nozzle I1 being doaxial with and extending through the regulating nozzle I5. 'I'he upper end (Fig. 1) of the body portion I8 of the forcer nozzle I1 is shaped `to constitute an annularvalve seat with which cooperates the main steam-admission valve- Il (Fig. 2). Passages I3 lead from a point just tances between the pins 31 and 35 and the fulcrum pin 32'" will be determined with reference to the relative sizes of the steam and water valves. This ratio is so calculated that the steam supply valve may be opened to maximum capacity well before the water valve vhas been4 opened to full capacity, and thus, further movement of the actuating handle in the same direction, although not affecting the quantity of steam delivered, varies the amount of water which may enter the injector. steam valve is at full opening, the water supply maybe regulated by manipulating the same handle and without reducing the steam supplied. Obviously,` by using valves of other, but wellknown types, it would be possible to obtain the desired regulation by the use of a single'handle,

even though the ratio of distance between the y` fulcrum pin 32l and the stems III and 23 were below said seat through the body portion Il'of the forcer nozzle to an annularuchamber 20 (Fig. 2) within the body portion I4 .of the regulating nozzle. regulating nozzle leads from-the chamber 2II.

The main steam-admission valve comprises a hollow skirt portion 22 (Fig. 2) provided with a removable -cap 23 thereby providing a chamber for the reception oil-a pilot valve 24 which normally seats against an annular valve seat 25 The annular flaring passage 2I of the within the skirt portion of the main valve. -A stem 26 fixed to the pilot valve 24 extends with clearance through an aperture 21 in the cap 23. and through a stumng box 28 carried by a plug 429 threaded into an aperture in the casing wall,

said valve stem'26 being coaxial with the regulating and forcer nozzles, the chamber in part 22 being of suchv axial depth as to permit u nseating the pilot valve before the latter engages the'cap 23.

A boss 30 (Fig. 1), projecting upwardly from 'the casing, receives a pivot pin 3l which passes through one end of a fulcrum lever 324 whose upper end is pivotally secured by a iulcrum pin 32a to one end of the valve-actuating lever 33., This lever is arranged to` swing in the plane of the axes of the two valve-stems 2|) and 26 and at an intermediate point in its length is provided with spaced elongate bearings 34 for'the opposite 4ends of a pin 35 extending from a cap or collar ilxed to the valve-stem Ill, the lever 33 comprising substantially parallel bars 33 and 33 (Fig. la) spaced to receive the valve stem I0 between them.

The free end of the ,lever 33 is provided with bearings 36 for. the ends of apivot pin 31 extending'from a collar nxed to the valve stem 2|. Intermediate these pins and 31, the lever.33 has bearings for a third pivot pin 38 -which is carried by a link 39 forming one element oi suitable connections leading to an actuating handle (not shown) located conveniently in the locomotive cab.

As illustrated, the relative location of the pivating handle is manipulated soas to swing the lever -33 about its fulcrum pin 32,

quite different from that herein specically sug- Sested. l

A second transverse septum 40 extends across the casing and forms Vthe bottom wall oi.' the water supply chamberJI. This septum 40 has an aperture, coaxial with the forcer nozzle. which receives the annular body portionI 42 of the water-regulating cone 43, saidcone constituting, `in effect, the firsty or throat section of the'multi-section combining tube, said cone having a converging annular throat '43 through which passes the free end portion ofthe forcer nozzle, the annular space between the wall oi this ,annular throat and the. forcer nozzle determining the quantity of water fed-to the forcer nozzle. In accordance withv the present inven' tion, auxiliary or emergency spillway passages 44 lead laterally from the converging throat 43a of the cone 43. These passages have no communication withthe usual overilow chamber and septum 40 `and a substantially parallel septum 43 which constitutes the upper end of the usual ISI) the arc of movement of the pin 31 is greater than that of the pin 35 and thus the rate of opening of the steam valve is greater than that of the water valve. When the actuating handle is ilrst moved, the pilot valve is separated from its seat, thus substantially balancing the pressure upon the lmain steam valve and making it easy to raise the latter from its seat. The ratio ordisvoverilow chamber, said septum having a screwthreaded aperture which receives'external screw threads lupon cone 42, the cone making leaktight contact with the septum.. I

The auxiliary spillway passages 44 have a combined area sulcient to pass substantially all of the steam delivered by the regulating nozzle I5 together 4with any water entrained thereby,l and in the event of abnormally high pressures in the combining tube and overflow chamber, such as may occur when the injector breaks, these auxf iliary spillways 44 prevent steam from backing up into the water chamber 4I by aiording a free exit to the atmosphere for steam'froni the regulating nozzle.

The second section 62 of the combining tube is supported by and as here shown is integral with the cone 43, there being a constantly .open spillway passage 63 between the delivery end of cone 43 and the receivingend o :the tube section 32.

The delivery end of the forcer nozzle I1 is here Theseptum 40 (Fig. 1) is provided with an open ended elongate guidefbearing 41, coaxial with the water valve 9, in which slides the cy- In other words, when the y y shown as just within the larger end of sectionv nipple portion 52l deiining a port leadingl from the chamber 52 and to which a waste water connection may be secured. When the valve 49 is seated, the outlet from chamber 45 is closed, but when the valve is unseated chamber 45 is vented directly and very freely to the atmosphere through chamber 52 and in that event pressures in chamber 45 are wholly unaffected by conditions in the main overflow chamber of the injector.

The end of valve stem is normally disposed closely adjacent to (but slightly spaced from) the head 53 of the main overilow valve (of larger diameter than the valve'49) designed at times to engage an annular seat 54 dening the upper edge of a passage in a web 55 extending transversely of the casing, said passage providing communication (when the valve head 53 is unseated) between the outlet chamber 52 and the main overowchamber 53a of the injector.

The stem 53x of valve 53 extends through a vertically elongate guide sleeve l56 (Fig. 1) having threaded engagement with an aperture in a web 51 and into a removable cap 58 having threaded engagement with the casing wall, said cap 58 being internally shaped to provide a cylindrical guideway 59 in which rlts a piston 60 secured to the end of the valve stem 5|. A port 12*3L leads from the delivery chamber 12 to the space within the cap 58 at the upper side (Fig. 1) of the piston 60, so that the upper side of the piston is always exposed to delivery chamber pressure. The valve stem 53x has a small axial ,passage 6| leading from the overflow chamber 53xl into the .closed end of this cap 58 (or altergether with the steam-admission valve and other parts not shown. However, if desired the manually actuated water control valve isv omitted, the water inlet then being provided with a check valve, not shown, generally similar to valve 5 above described, but having connections to the actuating handle whereby it may be used for throttling the water.

In the arrangement of Fig. 6,I the automatic overflow valve 49 of Figs. 1 and 2, is replaced by a valve 49x which cooperates with a seat 50X so as normally to close an annular port 45m leading from the chamber 45 directly to the atmosphere. The valve 49X has an elongate cylindrical guiding skirt 48x which slides in a guide sleeve 41X, the skirt having ports P which provide communication between the main overflow chamber 53a and the atmosphere when the valve 49X is fully open. A control rod 5|x, suitably gui-ded for axial movement, has one end normally disposed closely adjacent to the outer surface of the valve rst effects of opening the steam valve is to build natively the cap may have a small aperture in its closed end) thereby preventing the trapping of air in the closed end of the cap, insuring free movement of Ihe piston and affording escape for leakage, thereby preserving the desired unbalanced condition of the valve.

The third section 64 (Fig. 2) of the combining tube is removably supported by and in axial alignment with the fourth setcion 55 of the combining tube which in turn is supported by the delivery tube 66, it being noted that lateral spillways are provided at the points 61, 51ab and 68. The delivery tube 66 has an externally threaded body portion 69 which engages a threaded opening in the web 10. A removable cap 1I, having a screw-threaded engagement with the casing I, provides a chamber 12 into which the jet is'discharged by. the delivery tube 66, said chamber 12 communicating freely with the delivery chamber 13 from which leads a delivery opening 14 with which cooperates the line check valve 15. A nipple 16', integral with the casing, provides for connection of the boiler feed pipe.

Since the caps 29 and 1| are in alignment with the nozzles I5 and I1 and the tube sections, angd since the caps I2 and "58 are in axial alignment with the water and overow valves 9 and 49, it is possible to machine'the valve seats and threaded apertures without dirllculty and to install or withdraw the various operative parts at will, even* though the casing' .be of unitary one-piece construction. V

In Fig. 6 a modied construction is suggested,

wherein the essential elements of the injector are 64, etc. and the main overflowchamber 53, to-x up pressure in the main overflow chamber 53a and in response thereto the valve 49X moves away from its seat. At an early stage in such movement it uncovers the port leading from chamber 45, thus freely venting the auxiliary spillway passages 44 to the atmosphere. Soon thereafter the ports P are uncovered to permit water to overflow from the chamber 53. However, when the delivery jet has been actually established, pressure in thechamber 53 normally drops to subatmospheric and the valve 49x is thereby auto- Imatically closed, thus closing the ports P and also closing the outlet from the chamber 45. Obviously, if the injector should break while the steam-admission valve is open, the resultant back pressure in chamber 53 willinstantly open valve 49x thus automatically restoring the parts to. starting position.

Assuming that the injector is idle and that its several parts occupy the relative positions substantially as illustrated in Figs. 1 and 2, the operator may start the device into action byso moving the link 39, by means of the control handle, as to swing the lever 33 in a clockwise direction. as viewed in Fig. 1. This movement of the lever 33 results in a simultaneous axialmovement of the .valve stems II) and 26, respectively, but since the pivot pins 35 and 31 are located at different distances from the fulcrum pin 32, the valve stems will move at diierent speeds.l 'Ihus as illustrated, the lever arm 32a-31 is twice as long as the lever 32-35 and thus the steam valve stem will move twice as fast as the water valve stem. At this point it may again be noted that the diameter of the water inlet valve 9 is substantially greater than that of the steam-admission valve I8. If, for specific example, it be assumed that for full opening the water valve 9 must move a distance of 1%; of an inch and that maximum opening of the steam valve I8 requires ,a movement of 116 of an inch, it may readily be seen that when the water valve is fully open the steam valve will have moved twicell of an inch.

. opening.

" overflow chamber. 53,

-aseaeea v H or /16 of an inch, and .that when, on the reverse movement, the water valve has been half closed,

or is 1% of an inch open, the steam valve is still 1%; of an inch open, that is to say,well beyond its maximum effective opening. It therefore follows that in starting the injector, the steam valve reaches full open position when the water valve is less than half open, and that continued movement of the single actuating handle in the opening direction after the steam valve is fully open results in a further, idle movement of the steam valve but in an effective increase in opening of the water valve. Thus a substantial regulation of the amount of water admitted to the chamber 4I is possible by moving the actuating handle lback and forth after it has been swung far enough 53a .immediately unseats the valves 53 and 49,J thus restoring the parts to starting position, with to open the steam valve to maximum effective lDuring the linitial actuation of the operating handle the steam valve leads the water valve, thus always assuring an adequate supply of steam, and permitting independent control of the water supply when the steam is entering inv full volume, but without necessitating the employ- I ment of a separate handle for varying the water Supply- The rst effect of moving the steam valve stem 26 is to unseat the pilot valve 24, thus admitting steam in sumcient quantity to the under sidefof 'the main valve partially to balan-ce the latter,

and thus to make it easy to unseat the main valve by continued movement of the stem 26. A s the steam passes from the chamber 3 and through the open main valve, some of it flows through the passages I9 into the chamber 20, from whence it passes through the throat of the regulating or entraining nozzle I5 into the large or entrance end of the converging throat 43a of the regulating cone 43. This steam delivered from the nozzle I5 entrains water from the chamber 4I and delivers it into the throat 43 wherein the steam is partially condensed. A much larger volume of steam passes directly through the forcer nozzle I1 and enteringthe main overflow chamber 53' establishes therein a superatmospheric pressure. This pressure, acting upon the valve 53, unseats the drop and the valves 53 and 49 thereupon close injector break 'due for instance to lack of feed water the result ant back pressure in chamber the result that the injector willrestart without attention from ',the operator and without substantial loss of feed water. It may be noted that the valve 49 is substantially balanced as respects pressure variations in the' spillway passages 44, and that thevalve 53 is normally held closed during' operation of \the apparatus by pressure from the delivery chamber 13 acting (through the port 12a) upon the upper side (Figal)` ofthe piston 621.A After the injector hasthus been placed in operation,.manipulation of the actuating handle within a range above that effective fully to open the-steam valve, vwill move the water valve so as'to regulate the amount of water supply. 'To shut down the injector it is merely necessary to actuate the handle so as to swing' the lever 33 in a counterclockwise direction until both the steam and water valves are closed.

Referring toFig. 7 of the drawings, which illustrates another and preferred lembodiment of the invention, the numeral Im indicates the casing ofthe injector, said casing corresponding ingeneral to the casing I above described, having the screw-threaded nipple 2m to which the steam latter, thus providing `free communication bef tween the main overflow chamber 53a and the I atmosphere. As the valve 53 unseats it engages the end of the stem 5I and thus unseats the valve 49, thus connecting the auxiliary spillway passages 44 ,in the cone 43 ldirectly with the atmosphere. AResistance to the forward travel of the steam and water within the entrance to the throat 43a is thus immediately reduced and this i reduction in pressure at this point has been found tov be highly effective in the rapid establishment of Vhigh velocity ow through the cone 43 and into the first combining tube section 62. Since the passages 44 are vented directly to the atmos- Apher e, the'pressure within the-throat 43a yis in no way affectedl by pressure variations within the The steam which is delivered by, the nozzle I5 into the throat 43* is condensed and loses pressure and some of the lentrainedmater and condensate pass on through the narrower part of the throat 43a to the spillway 63 where the water meets steam delivered through the forcer nozzle and condenses some of this steam', thus further adding to the velocity of the jet. the several spillways, 63, 61, 61a and 68, functioning in the usual manner until the jet through the delivery tube 66 has been fully .supply pipe may be connected 'and having the steam inlet chamber 3m, and also having the screw-threaded nipple 4m to which the feed water hose is connected and which gives access to the water Vinlet chamber 6m.

The casing has a transverse septum provided with an aperture defined by an annular valve seat 8m with which cooperates the water-admission valve 9m. This valve has an actuating stem Im which passes out through'a stuffing box in a removable cap |21.

A partition I 3m separates the steam inlet cham- Y ber 3m from the water inlet chamber 6m, and that portion of this septum which forms the lower wall of the steam inlet-chamber 3m is provided with a screw-threaded opening which receives the 'externally screw-threaded body portion of the regulating oriifting nozzle 15m (Fig. 8).' The body portion of the regulating nozzle is internally screw threaded to receive the externally screwthreaded body portion' I6m of the forcer nozzle established. Upon establishment of the jet the j pressure in the overflow. chamber 63* tends to Ilm, the latter having the upwardly extending cylindrical portion |10 (Fig. 8) constituting a guide for, the main steam valve Ism which controls the delivery of steam to the regulating and forcer nozzle. -'The valve I8m is annular and provides a seat for the pilot valve 24m, the latter having limited movement relatively to'the main valve as determined by the removable bushing or cap 2 3m secured to the skirt of the main valve. 'Ihe pilot valve'24m is integral with the lower end of the actuating stem 26m which passes out ,through a stuffing box in the cap 29m.

A boss 30m, integral with the casing Im, provides a bearing for a pin forming a pivot for the lower end of the fulcrum'lever 32m. This lever swings in the plane of theaxes of the two valve stems lum and 26m, and its upper end forms a fulcrum for the valve-actuating lever 33m which is pivotally connected to the-upper ends of the valve stems Hlm and 26m, respectively, and whose free end is pivotally secured to an actuating link 39m forming one element of suitable connections leading to an actuating handle (not shown). The

relative location of the pivot pins which connect the valve stems to the lever 33111 may be as above described with respect to the structure shown in Fig. 1. While this relative arrangement of the pivot pins is desirable when valves such as here illustrated are employed, it is to be understood and Ois obvious that if the water-admission and steam-admission valves be of diierent types or different relative dimensions, the ratio of distances between the fulcrum point of lever 33111 and the pins which connect it to the respective valve stems may be different from that here shown without affecting the proper sequence of operation of the valves.

In the arrangement shown in Fig. 7, two parallel partitions or septums 46111 and 40111 extend transversely across the casing, being spaced apart to provide between them the upper portion 45111 of a spillway conduit. In this instance the septum 40111 is screw threaded for the reception of external screw threads'upon the exterior of the water-regulating 43111, said cone constituting the upper or first member ofthe combining tube.

The body portion |6111 of the forcer nozzle is furnished with passage |9111 (Fig. 8) which lead from a point immediately beneath the main valve |8111 into an annular chamber 20111 from which leads the flaring annular passage 2|111 of the regulating nozzle |5111, said annular passage 2|m being here shown as terminating substantially at the entrance end vof the regulating cone 43111. The forcer nozzle |1111 extends down into the water-regulating cone 43111, terminating substantially at the level of thespillway chamber 45111, the combining tube being provided with the auxiliary spillway openings 44111 leading from its interior into the conduit. 45111. The combined area of thesespillway openings 44111 is preferably suilicient to accommodate the maximum volume of steam which may be delivered by the regulating nozzle |5111 together` with the water which is entrained by said steam.

The casing is provided with an internal septum 55111 having an aperture defined by the annular valve seat 54111 with which cooperates the automatic overflow valve 53111. This valve is provided with a stem 5311 which slides in a cylindrical guideway 56111 provided in a cap 58111 which is screw threaded into the casing wall. This cap is shaped to provide a chamber 59111 which communicates by means of a pipe 51111 with the delivery chamber 12111.

The septum 46111, above referred to, is extended across the casing to provide the dividing wall 50111 which defines the lower part 4511 of the conduit 45111, separating said conduit from the usual overflow chamber 531. The overflow valve 53111constitutes a closure for the outlet end 45' of the conduit 45111-4511 and also for the outlet port 531 leading from the overflow chamber 531, the valve 53111 being arranged to seat upon the seat 54111 and also (preferably with a slight clearance) against the lower edge of the wall 50111. During the operation of the injector, the valve y53111 is held seated by fluid pressure acting beneath the valve head, the pressure thus acting on the valve head being that which subsists in the delivery chamber 1211.

The combining tube comprises a second section 62m and a third section 64111 having their ends spaced to provide the spillway passage 51111 opening into the usual overflow chamber 53'. The combining tube also comprises the fourth section 55111 which is spaced from the delivery end of the section 64111 to providel the 'spillway passage 61' leading into the overflow chamber 531. Between accesos the delivery end of the combining tube section 65111 and the receiving end of the delivery tube 61111 is another spillway passage 68111, also leading into the overflow chamber 5311. Itis to be understood that the spillway passages 61111, 61s and 68111 and tapers of the tube sections 62111, 64111, etc. are proportioned to accommodate the flow of steam from forcer nozzle |1111 upon starting and the flow oi mixture during operation, said spillways and tube proportions being in general of conventional size and, arrangement such as commonly used in in injectors of the open overflow type, the spillways being of properly limited capacity to avoid substantial interference with the uninterrupted delivery of the water against a high boiler pressure when once the delivery jet has been established.

A line check valve 14111 is arranged coaxially with the delivery tube 86111 and is operative to close the end of said tube when the injector is not in operation, assisted by the spring D and any pressure within the delivery chamber. This check valve 14111 has a tubular guiding stem and may be held to its seat, when the injector is idle, by a spring (not shown). When' the delivery jet is established, a pressure is built up in the chamber 59111 sumcient to close the overiiow valve 53111 and to hold it closed during the operation of the injector. When this valve is seated, it lcloses the conduit 45111 and thus makes virtually ineiective the primary orauxiliary spillway 44111, the'latter being operative to deliver steam and water only during the starting of the apparatus.

The injector is started into operation in the same way as that above described, by so actuatlng the handle as to swing the lever 33111, thus unseating the Water and steam valves, the steam valve leading the water valve. When the main steam valve is unseated, steam flows in large volume through the forcer nozzle |1111 and also, but in very considerably smaller volume, through passages |9111 into the chamber 20111 and thence through the entraining nozzle |5111 into the entrance end of the combining tube section 43111. By reason of the great volume of steam delivered Y by the forcer nozzle there is a tendency to estabvmay not previously have opened in response to gravity. However, if cold water is available for entrainment by the steam from nozzle |5111, the delivery of this water into the combining tube throat quickly condenses steam delivered by the nozzle |1111, reduces the pressure in the converging passages -of the combining tube, and although in the initial stages of the operation steam and water may pass out of the lateral spillways, some into the conduit 45111 and the rest into the overflow chamber 53S, the result-of the rapid condensation is that an extremely high velocity is quickly established inthe combining and delivery tubes andgasuiilcient pressure set up in the chamber 12111to o'pen thecheck valve and deliver the entrainedwater into the boiler, the high pressure iluld in chamber 12111 acting through pipe 51111 on piston 5311 to reseat the valve 531.

, However, if for any reason, either at the outset of the operation-forl during the operation of the injector, the suppl'yof water should be cut off, as for example by an ,abnormally low water level in the tank, th'e breakage of the supply'hose or otheraseaoae f wise, vor if the feed waterbe too hot, condensation will not take place with sumcient rapidity in the combining tube, and the volume of high pressure steam delivered by the forcer nozzle l1m tends to establish high pressure in the combining tube and also in the overflow chamber 53a.' If it were not for the primary orauxiliary spillway'passage 44m, the back pressure thus developed might besuivalves, andl means for actuating .said valves,- the tube assembly being provided with a plurality of i. longitudinally spaced spillways, one of said spillcient to cause the steam to back up through the entrance-end of the combining tube, overcoming the entraining action of the small volume of steam delivered by the nozzle m, and thus blow back through the open water inlet valve 9m and into'the supply hose, burning the latter and overheating such water as may be in the hose or' tank. v

However, by the provision of the primary or auxiliary spillway 44m, `which is Aof large capacity, any vbacking up of hot steam into the water inlet chamber 4ln is substantially prevented, since this passage 44m provides a direct outlet through the `chamber 45m to the atmosphere, it being noted that the overflow valve 531,In is normally'unseated either by Igravity or positively by over'ow chamber pressure when the injector is not forcing water into. the boiler. Thus, if the injector break during operation, the valve 53 immediately opens, providing a direct escape for such steam as is-delivered by the nozzle |51, together with any water` which may be entrained by said steam and also affording an outletfor steam which may back up in the second section of the combining tube, and thus when cool feed water again becomes available, the entraining nozzle l5lu is able to start this water with' substantial velocity into the` cone 53rn and in suicient volume to condense the steam emerging from the end of the forcer nozzle Ilm, thus very quickly and automatically reestablishing the delivery jet. On the other hand, when once the jet has been established, the spillways 61m, 61S, 68m, etc., function in the usual manner a single manually actuable element forstarting it into operation, for regulating the watersupply, and for stopping it'at the end of the operation; the overflow valve or valves is or are automatic in action and closed while the injector-is in' full operation and when idle, but open during starting; and these valves open automatically if the injector should break during use.

ways being so located and of such capacity as to clear the steam from the entraining nozzle thereby to permit the latter to draw water, and the others being arranged to clear the steam from the forcer nozzle thereby to prevent excessive back prssure within` the combining tube while the steam and water. valves are moving to full open position, means providing a conduit leading directly lfrom the i'lrst spillway to the atmosphere, the other spillways opening into an over- -iiow chamber within\ the casing, and a single automatically actuated overflow valve for closing said conduit and also the 'outlet from the overflow chamber andto keep them closed during the'normal operation of the injector and subsequent regulating movements of the steam and water Valves, and pressure motor means, respon-v sive to delivery jet pressure, for moving said single -overflow valve to closed position.

2. A steam jet pump of` the class described comprising a casing which houses a vsteam-admission valve and. a water-regulating valve, seats with which said valves cooperate, a single actuating/handle for the valves, and connections from said handle to the valves, the diameters of proved injector is of automatic type and has but While certain desirable embodiments of the invention have herein been illustrated by way of example, it is to be understood that the invention 'is not limited to these precise embodimentsA but lis to be regarded as broadly inclusive' of any and vall modifications falling within the scope of the appended claims.

I claim:

l. A steam jet pump of the kind having a. casing which h ouses a tube assembly including a converging combining tube and a deliverytube, steam nozzles arranged to deliver water-entraining and forcing Jets into the entrance end of the "combining tube, steam' and' water-admission the valves being such and the actuating connections being so constructed and arranged that,

movement of ther'handle in one direction causes the steam -valve tok reach full effective opening before the water valve is fully open so that continued movement of the handle in the same dir rection thereafter moves the steam valve idly while progressively increasing the opening of the water valve.

3.^A.steam jet pump of the class described comprising a casing which houses a steam-admission valve and a water-regulating valve, seats with which said valves cooperate, said valves having actuating stems, an actuating lever,lmeans including pivot elements uniting each stem to the lever, fulcrurn means for the lever, and'manually actuable'means for swinging the lever, the ratio of distances between the respective pivot elements and the fulcrum means being such that,

the steam valve moves Vaway fromits sat substantially faster than does the water valve when the lever is swung.

4. A steam jet 4vpump of the class describedY` comprising a casing which houses a steam-admission valve and a water-regulating valve, seats with which said valves cooperate, said valves having lactuating stems,'a lever, means including pivot elements uniting leach stem to the lever, fulcrum means for the lever, manually actuable means for swing the lever, the ratio of distances between the respective pivot elements andthe fulcrum means4 being such that the steam valve will reach full v'effective opening when the water valve has been opened only approximately onehalf way. l

5. A steam jet pump'of-the kind having a tube assembly provided with a series of spaced spillways, means-providing a conduit leading-from the rst' vof said spillways to the atmosphere, means providing a space of limited capacity with which later spillways of the series always communicate,v means providing a conduit leading from said .space to the atmosphere, and valve` means for closingv both of said conduits, and pressure motor means, responsive to delivery jet pressure, when the delivery :let is established, for

conduit leading directly from said first spillwayv to the outside of the casing, the other spillways discharging into a main overflow chamber within the casing, a main overfiowvalve controlling the delivery of fluid from said overflow chamber, automatic means for closing said auxiliary overflow conduit, and means operative concomitantly and positively to close the main and auxiliary overflow valves when the delivery jet is established.

7. A steam jet pump of the kind having a tube assembly provided with a series of spaced spill- Y Ways, the first of said spillways being of substantially greater capacity than any of the others, means providing a conduit leading from the flrst of said spillways lto the atmosphere, means providing a chamber which always affords communication between the outlets of the later spillways of the series, means providing a conduit leading from said chamber to the atmosphere,

lateral spillway, said spillway valve opening automatically in response to superatmospheric pressure in the overflow chamber, and pressure motor means operative to close said spillway valve when the delivery jet is established.,

. 10. A steam jet .pump of the kind which includes a combining tube having a spillway leading to an overflow chamber, an overflow valve operative to control the escape of fluid from the overflow chamber, a delivery tube, a steam-admission valve, a forcer nozzle arranged to deliver a steam jet into the entrance end of the combining tube, an entraining nozzle coaxial with the forcer nozzle, and means providing a conand a single valve operative automatically to close both of said conduits when the delivery jet has been established.

8. A steam jet pump of the kind having a lcasing which houses a combining tube having a plurality of spillways leading into an overflow chamber within the casing, an overflow valve operative to control the escape of fluid from the overflow chamber, a steam-admission valve, a delivery tube, regulating and forcer nozzles arranged to deliver steam jets into the entrance end of the combining tube, a regulating cone arranged to provide an annular convergent throat coaxial 1 with the forcer `nozzle and terminating adjacent to the delivery end of the latter, characterized in having means providing a spillway leading directlyl to the outer atmosphere from a point vergent annular passage into which the entraining nozzle delivers combined steam and water, characterized -in having an auxiliary spillway leading directly to the outer atmosphere from said annularpassage at a point rearward, in the direction of flow, of the delivery end of the forcer nozzle, a valve normally closing the auxiliary spillway, said overflow and spillway valves being arranged to open in response to the initial admission of steam to the nozzles, and motor means responsive yto the pressure of the delivery jet when established to close the overflow and spillway valves.

' 1l. A steam jet pump of the kind which includes a combining tube having a spillway leading to an overflow chamber, a delivery tube, a steam-admission valve, a forcer nozzle arranged to deliver a steam jet into the entrance end of the combining tube, means providing an entraining nozzle coaxial with the forcer nozzle, and means providing a convergent annular passage into which the entraining nozzle delivers combined steam and water, characterized in having an auxiliary spillway leading directly to the outer atmosphere from said annular passage at a point rearward, in the direction of flow, of the delivery end of the forcer nozzle, a valve for closing said lateral spillway, and pressure motor means responsive to superatmospheric pressure in the overflow chamber for opening Vsaid valve, and pressure motor means responsive to delivery jet pressure when the delivery jet has been establishd to close the spillway valve.

intermediate the ends of said convergent throat,

and a valve for closing said latter spillway, the spillway valve being coaxial with the overflow valve, and pressureymotor means arranged to close the overflow valve upon the establishment of delivery jet pressure, and means for transmitting motion from the overflow valve to the spillway valve thereby to close vthe latter when the overflow valve closes.

9. A steam .iet pump of the kind which includes a combining tube having a plurality of spillways leading to an overflow chamber, an overflow valve operative to control the escape of fluid from the overflow chamber a delivery tube, a steam-admission valve, a forcer nozzle arranged to deliver a steam jet into the entrance end of the combining tube, an entraining nozzle coaxial with the forcer nozzle, .and means providing a convergent annular passage into which the entraining nozzle delivers combined steam and water, characterized in having an auxiliary spillway leading directly to the outer atmosphere from said annular passage at a point rearward, in the direction of flow, of the delivery end of the forcer nozzle, and a valve for closing said 12. A steam jet pump of the kind having a casing which houses a combining tube having a lateral spillway leading into an loverflow chamber within the casing, a steam-admission valve, a delivery tube, regulating and forcer nozzles arranged to deliver steam jets into the entrance end of the combining tube, a septum defining the upper end of the overflow chamber, means providing a spillway leading laterally from the combining tube at a point between said septum and the entrance end of the combining tube, said latter spillway extending directly to the outer atmosphere and being of such capacity as to pass substantially all of the steam delivered by the regulating nozzle and the water which is entrained by said steam, a valve for closing said latter spillway when the delivery jet has been established and motor means responsive to the pressure of the delivery jet for closing the spillway valve.

a delivery tube, regulating and forcer nozzles arranged to deliver steam jets into the entrance `end of the combining tube, a septum defining the upper end of the overflow chamber, said sepescasas tum having therein Pan aperture in lwhich the combining tube lits substantially leak-tight, the' septum constituting the upper end wall of the overflow chamberymeans providing 4a lateral spillway in the wall of the combining tube at a point between said septum and the entrance` end of the combining tube, means providing a conduit leading from said latter spillway directly to the atmosphere, and a pressure controlled automatic valve operative to close the delivery end of said conduit when the vdelivery jet hasbeen established.

v l4. A steam jet pump of the kind having a casing which houses a multi-section combiningdelivery tube having lateral spillways between its vseveral sections, a steam-admission valve, a delivery tube, :regulating and forcer nozzles arranged to deliver steam jets into theentrance end of the combining tube, the first of said spillwaysbeing of suilicient capacity to pass substantially all of the steam delivered by the regulat- 1 cludes a combining tube having a spillway lead# ing nozzle, together with the water entrained thereby, said first spillway being so located that it does not directly receive steam forming the jet from the forcer nozzle, means providing a' 25 conduit leading from said first spillway to the outside of the casing, the other spillways discharging into an overowchamber within the casing, and a single automatically actuated valve arranged to close the delivery end of said con duit and alsoto close the discharge port from the overilow chamber when the delivery jethas been established.

15. A steam jet pump'of the kind having a casing which houses a combining tube having a plurality of spaced lateraljspillways leading into an overflow chamber within the casing,. a steamadmission valve, a delivery tube, regulating and forcer nozzles arranged to deliver steam jets into the entrance end of the combining tube, a partition defining the upper end .of the overflow chamber andmeans providing'aspillway leading from a point above said partition and below the delivery end of the regulating nozzle, said spillwayy extending' to the outer atmosphere, and a single automatic pressurefactuated. valve operative to close the delivery end of said spillway and also to close'a port leading from the overow chamber when the delivery iet is established.

16. A steam jet pump ofthe kind whichrin- 'l'o lng to an' .overflow chamber, a delivery tube, a steam-admission valve, a forcer nozzle arrangedl v to deliver a steam jet into the entrance end of `the combining tube, an entraining nozzle, and means providing a convergent annular passage into which theentraining nozzle delivers combined steam and water, characterized in having an auxiliary spillway leading directly to the outer 10 atmosphere from said convergentA annular p'assage at a .point intermediate the ends of said passage,an auxiliary overflow valve having a cylindrical skirt portion normally closing the outlet `from said auxiliary spillway, said valve, when open, providing free and direct communication between the auxiliary spillway and the outer atmosphere, a main overow valve normally closing a port leading from the main overow chamber, said main overflow valve being arranged to vopen in response to superatmospheric pressure within the main overflow chamber, and means for transmitting motion fromthe main overe.

the combining tube, an entrainingno'zzle, and

vmeans providing a convergent annular passage into which the entrain-ing nozzle delivers combined steamfand water,`characterized in having an' auxiliary spillway leading directly to the outer v atmosphere from apoint intermediate the ends of said annular passage, an auxiliary overow valve normally closing said auxiliary spillway, said valve being so arranged as, when' open, to provide free and direct communication between 40 the auxiliary spillway and the outer atmosphere.

a main overflow valvenormally closing a Port leading from the main overilow chamber,v the main overiiow valve being arranged to open -in response to superatmospheric pressure in the main overflow chamber, and a rigid member opyerative to transmit motion from the main overflow to the auxiliary oziveriilow` valve for openingv the latter. WALTER. Erdman

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