US2056698A - Injector - Google Patents

Description

t, F.- w. wALcH INJECTOR llllllllllll @et 69 19360 "F W, WALCH l l INJEcToR v 'Filed May 1'7, 1955 2 sheets-sheet 2 Patented Oct. 6, 1936 UNTED STATES @FME INJECTOR Application May 17,

17 Claims.

This invention pertains to steam jet pumps of the type commonly known as injectors, and wherein the heat energy of steam is directly converted into mechanical energy for the purpose',

- for example, of forcing feed water into a boiler against a pressure which may be as great or greater than that of the steam supplying the jet, and relates more particularly toa method of and means for controlling the supply of steam to such an injector whereby to initiate the operation of the latter.

While of broader application and utility, the invention is here-in described and illustrated with reference to its embodiment in an injector of i5 the axial flow type, arranged as is usual in locomotive practice below the level of the feed water supply, so that it is not called upon to raise water from the supply. For more specific example, the

invention is herein disclosed as applied to an in- 0 jector in which a priming nozzle, having a manually adjustable steam supply, is arranged in concentric relatio-n to an inner forcer nozzle designed to receive steam in volume from the boiler or other supply, and to deliver it -at high velocity into the ilaring mouth of a convergent combining tube, into whose open end the forcer nozzle preferably projects; the narrow end of the combining tube being adjacent to and in axial alignment with the narrow end of a divergent delivery tube.

When such an injector is stopped, its several passa-ges become substantially lled with water, and, if, in restarting, the steam admission valve be suddenly opened anywhere near to full capacity, the inertia of the water in the injector passages is such that the applied steam pressure cannot immediately expel the water through the narrow passages of the combining and delivery tubes. The injector parts are thus subjected to hydraulic pressures tending to produce leakage or permanent distortion of the parts, and the water tends to blow back into the supply pipe. If the water is thus driven back along the supply pipe7 the injector can not readily be started, and since the steam follows the water into the supply pipe, the hose connection may be burned and the feed water unduly heated.

As the result of a long series of experiments, it has been discovered that greatly improved results may be obtained if in initiating the opera-- tion of the injector, steam in relatively small amounts be'iirst admitted to the injector, thereby gradually to buildv up pressure in the latter sufficient to start the water gradually into motion, and eventually to expel it from the injector 1935, Serial No. 21,933

(Cl. 10B-268) chambers, and in p-articular that the gradual admission of steam first to one nozzle and subsequently to the other nozzle, results in a greatly improved, more efcient and certain starting of the injector than has heretofore been known, and that by following such procedure danger of damage to the parts, burning of the hose connection, and undue heating of the feed water is avoided.

In accordance with usual practice, the regulable admission of steam to the priming nozzle is controlled by a manually adjustable valve to which steam is supplied through the same conduit which leads the steam to the forcer nozzle. The admission of steam to this conduit is in turn controlled by an admission valve of quick-opening type having no provision for holding it at any point intermediate its fully opened and fully closed positions. Such a quick-opening typ-e of valve is requisite for practical considerations, but, even if it. were attempted to do so, it would be practically impossible to manipulate such a valve so as to bring about a gradual admission of steam to the injector by reason of the conditions encountered in a locomotive cab, where swaying, bumping and unexpected lurches seriously interfere with any attempt of delicate adjustment of operative parts. Moreover, even were it possible to open the usual admission valve gradually, corresponding amounts of steam would simultaneously be delivered to the priming and forcer nozzles, and this procedure is found to be substantially less eflicient than gradually to supply the steam rst to one nozzle and then to the other.

Accordingly, one object of the present invention is to improve the operation of starting injectors, and in particular to provide a novel procedure which includes as steps the gradual admission of steam first to one nozzleand then to the other nozzle, followed by supplying steam in full volume to one or both nozzles.

A further object of the invention is to provide apparatus appropriate for carrying out such improved method of operation in a simple and effective manner, in particular to provide, in combination with the injector nozzles, steam supply conduits and valves therefor, so designed and arranged as to permit steam gradually to enter one nozzle and thereafter to enter the other nozzle, and subsequently to admit steam in full volume to the forcer nozzle and in regulable amounts to the priming nozzle.

Other objects of the invention are to provide improved valve means Vas an element to the above combination, so designed as to afford a leak-tight cloure when the valve is shut, and having a main valve so balanced as to facilitate its opening against high pressures; to provide an admission valve of quick-opening type which is biased toward closed position by the steam pressure sufliciently to prevent it from opening accidentally in response to the shocks and vibrations to which it is subjected in use, and which is biased against closing when it is opened by the steam pressure, so that it will not accidentally be closed; further to provide a quick-opening valve of the type described, which during the early part of its opening movement, permits a relatively small amount of steam to flow between the valve feather and its seat until the valve has traveled a predetermined distance away from its seat.

Other objects and advantages of the invention will hereinafter be more fully set forth in the detailed description and by reference to the accompanying drawings, wherein:

Fig. 1 is a fragmentary vertical section through an injector of `the axial flow type, showing my improved steam controlling valve devices in combination with the injector structure;

Fig. 2 is a fragmentary vertical section through the steam admission valve showing the parts at the beginning of the opening movement;

Figs. 3, 4 and 5 are views similar to Fig. 2, but showing various stages in the opening of the valve, Fig. 5 showing the admission valve parts in fully opened position;

Fig. 6 is a vertical section on the line 6--6 of Fig. 3;

Fig. 7 is a fragmentary view, to larger scale, substantially on the line 1-1 of Fig. 6, showing details of the main admission valve feather, but omitting other parts; and

Fig. 8 is a fragmentary vertical section on the line 8-8 of Fig. 1, but to smaller scale.

Referring to the drawings, the numeral I designates a valve casing, which may be of any desired material and made in accordance with any usual and appropriate method. This casing comprises an inlet nipple 2, and primary and secondary outlet nipples 3 and 4, screw threaded or otherwise appropriately constructed for connection, respectively, to a steam supply pipe 5, and to delivery pipes 6 and 1 which lead to an injector. The interior of the casing is divided into an inlet chamber 8, and primary and secondary outlet chambers 9 and I0, by means of partitions or septums II and I2 having openings I3 and I4 (Fig. 5) constituting the main steam passages connecting the chambers 8, 9 and ID. The entrance to the passage or opening I3 is defined by an annular valve seat I5 (Fig. 5) and the walls defining the passage I4 in like manner provide, in effect, a valve seat for the inlet opening of the secondary chamber I0.

The casing also comprises an annular boss I6 coaxial with the Valve seat I5, and here shown as internally screw threaded for the reception of a guide member l1 having a tubular elongate guide portion I8 coaxial with the valve seat I5.

The passages I3 and I4 are furnished with substantially cylindrical walls I9 and ZIJ respectively, (Fig. 5) and the casing is also furnished with a substantially cylindrical guideway 2| forming in effect a cylinder coaxial with the valve. The valve feather or head 22 is of annular form and is provided with a plurality of spaced radial guide fins 23. This valve feather 22 is also furnished with a tubular stem 24 extending axially through the passages i3 and I4 and provided at its opposite end with an annular flange 25 constituting a balancing head. This head has an annular rim 2S adapted to slide in the cylinder defined by the wall 2I. Preferably this rim 26 has peripheral grooves to form a uid seal or packing.

An intermediate valve member 21, preferably formed integral with the stem 24, is arranged to slide into and out of the cylinder defined by the wall 29 of passage i4. The valve members 22 and 21 are so arranged that when the valve 22 is in fully closed position, as shown in Fig. l, the valve 21 is within and closes the passage I4, and when the valve 22 is in fully open position, as shown in Fig. 5, the valve 21 is wholly outside of passage I 4 so as to leave the latter open. As indicated in Fig. 2, when the valve is fully closed, the valve member 21 overlaps the edge III'L of passage i4, and if during use the parts wear and must be machined to provide new surfaces, it is requisite to preserve the initial distance between the right-hand faces of the valve members 22 and 21.

The valve feather 22 is provided with a surface 9! at its right-hand side (Fig. 1) adapted to rest against and make a fluid-tight iit when in contact with the valve seat l5. From this surface projects an annular flow-controlling baffle flange 23a Whose peripheral surface 32 is beveled (Fig. '1) so as gradually to recede from the wall of the passage I3.

The valve head or feather 22 is also provided with a tubular boss 33 projecting from its lefthand face, (Figs. l to 5) that is to say, from the side opposite that from which the stem 24 projects. This tubular boss provides a substantially cylindrical guideway or cylinder 34 for the reception of a cylindrical head or guide member 35 forming part of a pilot valve, hereinafter more fully described. This head 35 has limited movement within the guide cylinder 34, its movement to the left, as viewed in Figs. l to 5, being limited by a bushing 3E secured within the end of the tubular boss 33. The central opening in this bushing 36 is adapted to receive a valve actuating rod 31 provided at its right-hand end, as viewed in Figs. l to 5, with a disk member 38 adapted to iit and turn in a suitable slot in the head 35, thereby uniting the rod 31 to the head 35 in such a way as to insure a like axial movement of the parts while permitting relative rotation of the head 35 and the rod 31.

The rod 31 extends through the guide sleeve i8 and through a packing gland 39 at the end of the sleeve I8. At its outer end the rod 31 is furnished with a bifurcated yoke 4B having spaced bosses which receive the fulcrum pin 4I on which is pivoted an actuating lever 42. This lever has a short arm 43 (Fig. l) having a bearing opening for the reception of a pivot pin 4l! which is received in bosses at the outer ends of a pair of links 45. These links are in turn fulcrumed upon a pin 41 mounted in a pair of spaced bosses carried by or forming a part of a collar 49 mounted upon the tubular guide member I8. This collar 49 is normally held in fixed position on the member I8 by means of a nut 5G engaging the screwthreaded outer surface of the member I8. However, by loosening this nut, the collar 49 may be turned on the guide portion of sleeve I 8 so that the lever 42 may be positioned in any desired radial plane of the rod 31, and after having been adjusted to the desired position, the collar 49 may again be locked in place by means of the nut 59.

The tubular boss 33 of the main Valve 22 is furnished with one or more openings 54 leading from the inlet chamber 8 into an annular space 55 (Fig. 2) surrounding the outer or left-hand end of a tapered pilot valve 56. The stem 35 of this pilot valve slides freely in the cylindrical bore 34 in the boss 32, being so free, in fact, as to permit leakage of pressure fluid from the chamber 55 into ay second annular chamber 55EL (Fig. 4) just to the right of the inner end of the bushing 35.

The tapered pilot valve 53 is designed to seat against a tapered valve seat surface 5l (Figs. 2 to 5) defining the entrance to a canal 58 (Fig. 2) leading through the tubular stem 24 of the main valve 22 into a balancing chamber 50 at the right hand side of the balancing head 25, such chamber being formed in part by the space Within the rim 26 of the balancing head and in part by an outwardly projecting boss 5I of the casing. This balancing chamber 6I] communicates with the primary outlet chamber 9 of the valve casing by means of a suitable passage of restricted capacity, such passage here being shown as consisting of a small orice 62 directly through the wall of stem 2d. Obviously, the balancing effect of the head 25 varies inversely with the size of the orice 52.

The lower part of the casing is furnished with a transversely extending tubular member lll which is disposed below the primary outlet chamber 8 and extends diametrically across the upper part of the primary outlet nipple 3, as shown in Figs. 1 and 8. The inner or right-hand end (Fig, 1) of the member I0 is formed integral With the casing I and web I2 and its outer end is formed integral with the outlet nipple 4, thus providing a construction wherein the secondary outlet chamber I communicates directly with the secondary nipple (l, and the primary outlet chamber 9 communicates directly with the primary nipple 3. Suitable valve means may be provided for regulating the size of the duct leading from the secondary outlet chamber I0, and to this end the outer end of the tubular member lil is furnished with an inwardly directed annular flange or web having a beveled outer edge l2 which provides a valve seat.

The casing is also furnished with an annular boss 'M coaxial with valve seat I2 and which is internally screw threaded for the reception of a guide member 'l5 which supports a manually actuable Valve head lll. This valve head 'Il is provided with a stem 78 having a screw-threaded engagement with the inner end of the guide member l5, and the outer end of the stem projects through a packing gland 79 secured to the outer end of the guide member l5. The outer end of the stem may be provided with a suitable actuating handle 8S conveniently located in close proximity to the operating lever 42. An annular flange 82 is preferably formed integral with the outer end of the valve head Tl and is arranged to engage the inner end of the guiding member 'l5 to limit the outward movement of the valve ll.

The injector comprises the forcer nozzle 86 and the priming nozzle B9. Reference may be had to the patent to Walch, No. 2,032,674, dated March 3, 1936 for a description of an injector of this general type.

In the construction herein illustrated, the forcer nozzle is supplied through a duct 85 connected by pipe 6 to nipple 3, While the priming nozzle is supplied through a duct 86a connected y by pipe l to nipple 4.

The operation of the device is substantiallyr as follows:

Assuming that at the beginning of the operation the parts occupy the positions shown in Fig. 1, the operator seizes the lever 42 and swings it toward him, that is to say, in a clockwise direction, as viewed in Fig. 1. The rst effect of such movement is topull the pilot valve 56 to the left until it utimately reaches the position shown in Fig. 2. As soon as the pilot valve begins to unseat, steam or other pressure iiuid from the chamber 8 passes through the openings 54 into the annular chamber 55 and thence around the tapered valve 56 into the canal 58 and thence into the balancing chamber (StL-a part of the steam leaking through the openings S2 into the primary outlet chamber t. At the high pressures commonly employed, this operation is almost in-r stantaneous, and presure at once begins to build up in the chamber 9 and associated delivery duct leading to the forcer nozzle 86. This gradually increasing pressure drives out the condensate water which usually accumulates Within the injector casing when the injector is idle, thus clearing the injector for the admission of steam at the operating pressure and in operating volume. At this stage of the operation the valve 2l is still in a position substantially to close the passage I4 (Fig. 2) and consequently no steam is admitted to the secondary outlet chamber II).

rlhe operator continues to move the lever 42 in a clockwise direction (Fig. 1) and as soon as the head 35 of the valve 56 engages the inner end of the plug 36 (Fig. 3), the main valve 22 begins to retract from itsv seat I 5, this action being facilitated by the previous balancing of the steam pressures at opposite sides of the main valve. As the valve 22 begins to retract from the seat I5, presure fluid in substantial quantities would immediately begin to flow through. the passage I3 into the primary outlet chamber 9 were it not for the provision of the annular baille flange 23B. Since this baille flange has the beveled peripheral surface 32, the cross-sectional area of the annular duct between the flangey 232L and the wall of passage I3, does not increase as rapidly as the area between the surface 3l of the valve head and the seat I5, and consequently only a limited amount of steam is enabled initially to flow through the passage I3. Hence, even though the operator initiate the opening of the valve 22, with a jerk, the sudden admission of an unduly large amount of steam to the injector before the latter is fully clear of water is avoided.

The continued movement of the valve 22 toward the left (as viewed in the drawings) is accompanied by a corresponding movement of the valve disk 2l along the passage Ill, as shown in Fig. 3, and finally opens both the passages I3 and Irl to their full extent (Fig. thus admitting steam to both the primary and secondary chambers 9 and I0 in full operating pressure and volume. Thereafter, by manipulating the valve 'l1 the amount of water delivered by the injector may be regulated and the device will continue to operate even though the steam pressure may vary.

As already noted, it is Idesirable that the steam operation of an injector of the type illustrated that the steam enter the forcer nozzle and start the Water into motion longitudinally of the combining tube before steam in substantial quantity enters the priming nozzle. If steam in substantial Volume enter the priming nozzle prematurely before the body of water in the injector casing has been started into motion, the inertia of such water may be so great that the steam from the priming nozzle is forced back and, finding the least resistance at the water inlet, pushes the water back down the inlet and unduly heats the water and may burn the hose connection. On the other hand, if the steam enter the priming nozzle too late, the injector breaks, that is to say, it ceases or refuses to operate and must be started over again.

By the employment of the control disk 21, which, when the valve is in closed position, has a ,predetermined overlap beyond the entrance edge Ma of the passage 2li, it is possible very precisely and definitely to determine the point during the opening of the valve device at which steam in substantial volume shall begin to enter the priming nozzle. This point at which the operating steam in quantity shall be admitted to the priming nozzle is determined by the distance between the face Sl of the main valve head 22 and the right-hand face of the disk 2. This distance is predetermined by experiment, and the valve manuf'acturer machines the valve parts to provide this exact distance, so that nothing is left to the discretion of the user and correct results may always be expected.

In initiating the operation of the injector as above described, steam in relatively small amounts is rst admitted preferably to the forcer nozzle of the injector, thereby building up pressure sufficient gradually to start th-e water in motion. Then, when subsequently steam is admitted to the priming nozzle, it finds the water already in motion and does not tend to back up and drive the water down into the hose connection as is frequently the case when steam is admitted to the priming nozzle before flow has been started in the right direction. This insures a greatly improved, more efcient and reliable starting of the injector than otherwise would be possible, and eliminates the liability of damage to parts, burning of the hose connection and undue heating of the feed water.

In accordance with the arrangement shown, the surfaces of the valve 22 and the pilot valve 55 which are exposed to steam pressure are :so proportioned and arranged that when the valve 22 and the pilot valve 56 are seated, an unbalanced steam pressure is exerted upon them in such a direction as to tend to keep them closed. Thus, for example, as illustrated in Fig. l, the left-hand surf'ace of the valve 22 is exposed to the steam pressure in the chamber B while the right-hand surface of the balancing head 25 is not so exposed, so that the valve is held firmly against its seat. At the same time, due to leakage of steam into the chamber 55a, a preponderance of pressure is exerted against the pilot valve such as tends to hold the latter against its seat. Hence the jolting and bumping to which such an apparatus is subjected in locomotive practice is not likely to unseat the valves and allow steam to enter the injector.

On the other hand, when both valves are fully open, as illustrated in Fig. 5, there is a preponderance of pressure on the valve 22 in a direction tending to hold the latter open or away from its seat. Likewise, since in this position of the parts the left-hand face of the head 35 of the pilot valve engages the inner surface of the plug 36, there is a preponderance of pressure upon the right-hand side of the pilot valve, tending to keep the latter open. Hence, the jolting and vibration will not accidentally close the valve members. In fact, when the valve is open the actuating lever 42 must be moved away from the operator, that is to say, in a counterclockwise direction, as viewed in the drawings, beyond a definite and distinct point, in order to prevent the parts from reopening if the lever be released.

The pilot valve 56 and the cooperating conical seat surface 5l are accurately finished, as by grinding or the like, and preferably are of considerable length in an axial direction, so as to provide a reliably tight it.

By reason of the high pressures maintained in the chamber 8, the steam velocity is very high in the narrow passage between the pilot valve and its seat, especially when the pilot valve first begins to open. Heretofore in devices employing a pilot valve, great diiliculty has been experienced in keeping the valve tight, since the powerful erosive action of steam at such high velocities quickly scores Valves and seats of ordinary construction wherein the steam is compelled tochange its direction abruptly in passing between the valve and seat surfaces. However, by the use of a conical valve and valve seat surface the steam is not obliged to change its direction of flow, and thus far less erosion and consequent leakage takes place than is usual and the valve remains tight over a long period of use.

Preferably the cooperating conical surfaces of the valve and seat should be of substantial length so as with certainty to impart a rectilinear motion to the particles of steam before they are freed from control, and for best results a conical taper of the order 0f 30 more or less has been found desirable. Since this type of valve does not readily leak, even after long periods of use, the operation of the injector is greatly improved and an increased economy in operation is effected.

While I have shown and described one desirable embodiment of the invention, it is to be understood that this disclosure is for the purpose of illustration and that various changes in shape, proportion and arrangement of' parts, as well as the substitution of equivalent elements for those herein shown and described, may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

I claim:

1. A steam inlet valve for injectors, said valve comprising a casing having an inlet chamber and an outlet chamber, an annular valve seat delining a passage connecting said chambers, a valve head normally closing said passage, said head having a tubular stem extending through the passage and provided with a balancing member provided with an annular rim, a guide for said rim, the casing having a balancing chamber between said balancing member and a wall of the casing, a pilot valve normally closing the canal through said tubular stem, means operative to open the pilot valve, thereby to permit steam from the inlet chamber to flow through the valve stem to the balancing chamber, and means providing an escape passage leading from the balancing chamber to the outlet chamber thereby to x the degree to which the valve is balanced.

2. A steam inlet valve for injectors, said valve comprising a casing having an inlet chamber and an outlet chamber, an annular valve s-eat defining a passage connecting said chambers, a valve head normally closing said passage, said head having a tubular stem extending through the passage and provided with a balancing member provided with an annular rim, a guide for said rim, the casing having a balancing chamber between said balancing member and a wall of the casing, a pilot valve normally closing the canal through the tubular stern, said pilot valve, when open, permitting steam from the inlet chamber to flow through the stem to the balancing chamber, and means operative successively to open th-e pilot valve and to move the main valve head from its seat.

3. A steam inlet valve for injectors wherein water tends to collect when the injector is idle, said valve comprising a casing having an inlet chamber, an outlet chamber always communicat` ing with the injector, an annular valve seat defining a passage connecting said chambers, a valvev head normally closing said passage, said head having a tubular stem extending thr-ough the passage and provided with a balancing member provided with an annular rim, a guide for said rim, the casing having a balancing chamber between said balancing member and a wall of the casing, the tubular stem having an axial canal leading from the inlet chamber to the balancing chamber, means providing a passage of fixed predetermined dimensions furnishing communication between the balancing chamber and the outlet chamber, the valve head having a tapered pilot valve seat at the entrance to the canal through the tubular stem, a tapered pilot valve normally engaging said tapered seat, and means operative successively to move the pilot valve away from its seat and thereafter to unseat the main valve head.

4. A steam inlet valve for injectors in which water tends to collect when the injector is idle, said valve comprising a casing having an inlet chamber, an outlet chamber always in communication with the injector, an annular valve seat defining a passage connecting said chambers, Aa valve head normally closing said passage, said head having a tubular stem extending through the passage and provided with a balancing inember having an annular rim, a guide for said rim, the casing having a balancing chamber b-etween said balancing member and a wall of the casing, the tubular stem having an axial canal leading from the inlet chamber to the balancing chamber, means providing a passage of fixed predetermined dimensions furnishing communication between the balancing chamber and the outlet chamber, the valve head having a tubular boss coaxial with the stem but at the opposite face of the head, a tapered pilot valve provided with a guiding member sliding within said tubular boss, the main valve head having a taperedseat at the entrance to the canal through its tubular stem, manually actuable means operative to move the pilot valve away from its tapered seat, and an annular plug closing the outer end of said tubular boss and constituting a stop engageable by a part of the pilot valve after the latter is unseated, whereby upon furth-er movement of said manually actuable means the main valve head is unseated.

5. A steam inlet valve for injectors in which water tends to collect when the injector is idle, said valve comprising a casing having an inlet chamber, an outlet chamber always in communication with the injector, an annular valve seat defining a passage connecting said chambers, a valve head normally closing said passage, said head having a tubular stem extending through the passage and provided with a balancing member having anannular rim, a guide for said rim, the casing having a balancing chamber between said balancing member and a wall of the casing, the tubular stem having an axial canal leading from the inlet chamber to the balancing chamber, means providing a passage of xed predetermined dimensions furnishing communication between the balancing chamber and the outlet chamber, the valve head having a tapered valve seat defining the entrance to the canal through its tubular stem, a tapered pilot valve normally engaging said tapered seat to close said canal, said valve having a guiding member, guide means carried by the main valve head providing a limited path of movement relatively to the valve head for the guiding member of the pilot valve, and manually actuable means connected to the pilot valve and operative by continued movement in the same direction to unseat the pilot valve and move it to the limit of its path of movement with respect to its guide means and thereafter to unseat the main valve head.

6. In combination with an injector in which condensate water tends to accumulate when the injector is idle, control apparatus comprising a casing having an inlet chamber and primary and secondary outlet chambers, valve seats defining the entrances to passages connecting said inlet chamber to the primary and secondary outlet chambers, respectively, means providing primary and secondary outlet conduits, respectively, leading from said primary and secondary chambers to the injector, valve members normally engaging said seats to close said passages, one of said valve members being provided with a balancing head, means operative to admit pressure fluid to react against said balancing head before the valve members are unseated so as to facilitate opening said valve members, and means providing for the escape of some of the balancing pressure fluid into one of said outlet chambers thereby to initiate the expulsion of condensed water from the injector before the valve members are opened.

7. In combination with an inject-or in which water tends to accumulate when the injector is idle, control apparatus comprising a casing having an inlet chamber, primary and secondary out'- let chambers each communicating with the injector, valve seats defining the entrances to passages connecting the inlet chamber to the primary and secondary outlet chambers, respectively, a delivery duct of restricted capacity providing a communication between said inlet chamber and one of the outlet chambers, a pilot valve normally closing the entrance to said duct, primary and secondary valve members normally closing said passages, and means constructed and arranged rst to open said pilot valve and thereafter to open the primary and secondary valve members,v

thereby rst to admit a limited amount of steam to now through said restricted delivery duct to the outlet and thereafter to permit a much greater amount of steam to ow from the inlet to each of said passages.

8. The combination with an injector in which condensate water tends to accumulate when the injector is idle, said injector having a forcer nozzle and priming nozzle, of controlling means including parts defining steam supply passages leading to the forcer nozzle and the priming nozzle respectively, the passage which leads to one nozzle having a cylindrical entrance, an annular valve seat coaxial with said cylindrical entrance and defining the entrance to the other passage, a valve device comprising a main head engageable with the seat to close the corresponding passage, a piston for closing the cylindrical entrance to the -other passage, and a balancing head exposed at one side to a balancing chamber, a conical pilot Valve normally seating with a tight fit in a conical annular seat dening a duct for admitting steam to enter sai-d balancing chamber thereby to act on the balancing head,-there being a constantly open outlet from said balancing chamber to one of said passages thereby, when the pilot Valve is unseated, to permit balancing steam in small amount to enter the injector and initiate expulsion of condensate from the latter, and common means operative rst to unseat the pilot valve and thereafter to actuate the valve device so as successively to unseat the main head and to move the piston out of said cylindrical entrance.

9. In combination with a steam injector in which water tends to accumulate when the injector is idle, a steam inlet valve comprising a casing having an inlet chamber, an outlet chamber communicating with the injector, and a valve seat defining a passage connecting said chambers, a main valve head normally engaging said seat, a balancing member for said valve head exposed at one side to a balancing chamber, a pilot valve operative to admit balancing steam to said balancing chamber thereby to act on said balancing member, said balancing chamber having a restricted outlet of ixed area constructed and arranged to limit the balancing effect and to permit balancing steam in small volume to escape to the outlet chamber and thence to the injector thereby to initiate expulsion of water from the latter, and manually actuable means operative successively to open the pilot valve so as rst to initiate expulsion of water therefrom and thereafter to unseat the main valve head to admit steam in operating volume to the injector, the parts being so proportioned and arranged that, when open, both the pilot valve and the main valve head are biased toward open position by unbalanced steam pressure.

10. In combination with an injector in which water tends to accumulate when the injector is idle, control apparatus comprising a casing having an inlet chamber and primary and secondary outlet chambers each communicating with the injector, valve seats defining the entrances to passages connecting the inlet chamber to the primary and secondary outlet chambers, respectively, a movable stem extending from said inlet chamber through said passages, said stem having a canal of predetermined, fixed and restricted capacity leading from said inlet chamber to one of the outlet chambers, a pilot valve normally closing the entrance to said canal, primary and secondary valve members mounted on said stem and normally operative to close said passages, a manually operable lever, and connections between said lever, pilot valve, and stem operative upon movement of the lever first to 4open the pilot valve thereby to permit steam in limited volume to enter the injector to initiate expulsion of water therefrom and thereafter successively to open the primary and secondary valve members.

1l. Contro-l apparatus for use with an injector in which water tends to accumulate when the injector is idle, said control apparatus comprising a casing having an inlet chamber, outlet chambers each communicating with the injector, Valve seats dening the entrances to passages connecting the inlet chamber to the respective outlet chambers, a duct of restricted capacity providing a communication between said inlet chamber and one at least of said outlet chambers, means for normally closing said duct, valve members normally closing said passages and arranged successively to open the passage leading to one outlet chamber and then the passage leading to the other outlet chamber, baflle means associated with the valve which controls the passage leading to the first of said outlet chambers, said bale means restricting the flow of steam as the valve leaves its seat, actuating means for moving said valve members, and means responsive to the actuation of said valve moving means to open the closing means for said duct prior to separation of said valve members from their respective seats thereby to admit steam in small volume to the injector to initiate expulsion o water therefrom.

12. The combination with an injector in which water tends to accumulate when the injector is idle,said injector being of the type having a forcer no-zzle and a priming nozzle, of a control apparatus comprising a casing having an inlet chamber and primary and secondary outlet chambers, means providing conduits leading, respectively, from the primary and secondary chambers to the nozzles, means providing passages connecting said inlet chamber to the primary and secondary outlet chambers, respectively, a delivery duct of lixed predetermined restricted capacity providing a connection between said inlet chamber and one of the outlet chambers whereby at times to allow steam in small volume to flow from the inlet chamber to said outlet chamber and thereby to initiate expulsion of accumulated water from the injector, a pilot Valve which closes the entrance to said duct when the injector is not operating, main valves normally closing said passages but operative at times to admit steam in full volume from the inlet to the respective outlet chambers thereby to actuate the injector, flow control means operative, as one of said main valves leaves its seat, to permit a progressively increasing flow of steam, less than that which would normally result from the corresponding opening of said valve itself, to ow from the inlet into the passage controlled by said latter valve thereby to furnish steam for accelerating expulsion of condensate, and actuating means for the several valves.

13. The combinatio-n with an injector in which water tends to accumulate when the injector is idle, the injector being of the type having a forcer nozzle and a priming nozzle, of a control apparatus comprising a casing having an inlet chamber and primary and secondary outlet chambers, means providing conduits leading from the primary and secondary chambers, respectively, to the nozzles, means providing passages connecting said inlet chamber to the primary and outlet chambers, respectively, a valve operative to admit steam in small but predetermined quantity from the inlet chamber to one of the outlet chambers thereby to initiate expulsion of condensate from the injector,-valves, each of greater capacity than the iirst valve, operative, respectively, to admit steam in operating volume to the respective outlet chambers, control means associated with one of the latter valves operative, as said valve is opened, to limit the ow of steam therethrough to an amount substantially less than that which would normally result from the corresponding opening of the valve itself, thereby to provide an increased but limited volume of steam to accelerate expulsion of condensate from the injector, means preventing delivery of steam from the second of said latter valves until said control means has substantially ceased to function, and a single actuator for operating all of said valves.

14. A steam inlet valve for injectors in which water may accumulate when the injector is idle, said inlet valve comprising a casing having therein an inlet chamber and an outlet chamber, an annular valve seat dening a passage co-nnecting said chambers, a valve feather cooperable with the seat to close the passage, an actuating stem for the valve, an elongate tubular guide member projecting from a part of the casing, said guide member having a bore in which the stem slides, a packing gland at the end of said guide member to prevent leakage longitudinally of the stem, a co-llar encircling said guide member, the latter having external screw threads and a cooperating nut for clamping the collar in selected position of angular adjustment, a link having one end pivotally united to the collar, a valve-actuating lever pivotally united at a point intermediate its ends to the outer end of the valve stem, and means uniting the other end of the link to one end of the lever, the collar being rotatable about the axis of the stem by loosening said clamping nut whereby the valve-actuating lever may be rotated to any desired radial plane of the valve seat and constrained to swing for valve operation in said plane by again tightening the clamping nut.

15. The combination with an injector in which water tends to accumulate when the injector is idle, said injector being of the type having a forcer nozzle and a priming nozzle, of a control apparatus comprising a casing having an inlet chamber and primary and secondary outlet chambers, means providing passages leading from the primary and secondary chambers, respectively, to the nozzles, a valve operative to admit steam in small predetermined definite quantity to flow from the inlet chamber to one at least of the outlet chambers thereby to initiate expulsion of accumulated water from the injector, additional valves, each of greater capacity than the irst-named valve, operative, subsequently to the opening of said first Valve, to admit steam in operative volume to the respective outlet chambers, means associated with one of said latter valves, operative, as the valve is opened, to restrict the ow of steam through the valve to an amount substantially less than that which would result from the corresponding lift of the valve alone, thereby to admit steam in limited volume to accelerate expulsion of the condensate from the injector, and a single actuating member operative to move the several valves in succession.

16. The combination with an injector in which water tends to accumulate when the injector is idle, said injector having a forcer nozzle and a priming nozzle, of a control apparatus comprising a casing having an inlet chamber and primary and secondary outlet chambers, means providing passages leading from the primary and secondary chambers, respectively, to the nozzles, the passage which leads to one nozzle having a cylindrical entrance, a valve operative to admit steam in small predetermined definite quantity to ow from the inlet chamber to one at least of the outlet chambers thereby to initiate expulsion of accumulated water from the injector, an annular valve seat coaxial with said cylindrical entrance and having a valve-engaging surface disposed in a plane substantially perpendicular to the axis of said passage, said seat defining the entrance to the other passage and being spaced, axially, a predetermined distance from the receiving end of said cylindrical entrance, a valve head having an annular seat-engaging surface disposed in a plane substantially perpendicular to the axis of the valve seat and engageable with the valve seat, a piston xedly connected to the valve head and projecting a predetermined distance into said cylindrical entrance when the valve head is engaged with its seat, and flowlimiting means carried by the valve head and comprising a surface concentric with the seatengaging surface of the head and disposed at an angle to the valve-engaging surface of the valve seat, said flow-limiting means being operative as the valve leaves its seat, to permit a progressively increasing flow of steam less than that which would otherwise result from the corresponding opening of the valve itself to enter the passage controlled by said valve, thereby gradually and with progressively increasing velocity to expel water from the injector, and means operative to move the valve head away from its seat and concomitantly to move the piston to- Ward the Huid-receiving end of said cylindrical entrance.

17. The combination with an injector in which water tends to accumulate when the injector is idle, said injector having a forcer nozzle and priming nozzle, of controlling means including parts defining steam supply passages leading to the forcer nozzle and the priming nozzle, respectively, the passage which leads to the priming nozzle having a cylindrical entrance, an annular valve seat defining the entrance to the other passage, a valve device comprising a head having an annular seat-engaging surface c0- operable with the seat to close the passage to the forcer nozzle, a piston for closing the cylindrical entrance to the passage leading to the priming nozzle, means rigidly connecting the head and p-iston so that when the head engages the seat the piston extends a predetermined distance into said cylindrical passage thereby to close the latter, and an annular flange carried by the head and extending into the passage leading from the annular seat when the valve head is seated, said flange having a peripheral surface disposed in the path of steam escaping from between the head and seat thereby limiting the flow of steam to an amount less than that normally corresponding to a given valve lift as the head is moved away from the seat, said ange being of such axial length as to become substantially ineiective as the piston clears the receiving end of said cylindrical entrance during opening movement.

FREDERICK W. WALCI-I.

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