US2288777A - Injector - Google Patents

Description

July 7, 1942.

HQA. BNOSONEA'I'TOV ETAL- INJEcToR Filed June 5, 1941 INV ENT ORS Ma M ATTO R N CV.

Patented July 7, 1942 INJECTOR Henry A. Vinsonni-.0, cincinnati, and William Earl JSnyder, Silverton, Ohio, assi'gnors toThe Edna `Brass Mfg. Company, Cincinnati, Ohio, a cory poration of Ohio Application June 5, 1941, Serial No. 396,784 Y 6 Claims. (Cl. 1623-275) This invention relates 'to 'imprcvements'in an injector of the overflow type, and particularly to an automatic ncontrol for the overflow valve,V

and 4in the `provision yof a relief `to prevent the accumulation vof excessive Vpressure in the overflow chamber having a ltendency to disrupt the jet when lfeed water of high temperature ris-used, or for `any other reason.

Injectors of the type to which the present im` provements are directed have one or .more relief.

which would prevent the establishment of the` jet and the consequent starting. When sufficient velocity ofthe feed water .to overcome the boiler pressure is developed in the delivery tube of the injector, it is Vdesirable'to immediately Vclose the overflow Valve `and hold thesame `closed 'under suiiicient pressure to prevent `spilling or Idrawing in vof air. Conversely, if the Velocity of the feed water for any reason falls below that necessary to overcome boiler pressure, the overow valve must be free to immediately open to enable the requisite velocityV of the feed water to -be `again 3- attained for automatic restarting. Likewise, the

overflow valve must be permitted to open, should any .pressure develop in the overflow chamber through `the `use of feed water of -high temperature or other reason's'to avoid adisruption ofthe jet. l

In previous arrangementswhereby the overflow Valve is closed automatically after the injector is in operation, it has `been the practiceto provide valve controlled conduit or passage communication `between the delivery. chamber and apiston chamber for `controlling the operation of the piston bythe iluid pressureV in the delivery lchamber to close or control thefoverflow valve. These prior `arrangements either do not permitdependable restarting of the injector due to interruption in the @water supply, or` in the ajccumulation of a disturbing pressure `in the overflow chamber 'dueto tlieuse of feed water of high temperature. n j p l It is therefore `an objectof the invention to provide an injector with means to close the overflow valve automatically as soon as the delivery velocity is suicient to `enter the boiler, and to overflow valve during the normal operation of the injector, yet allowing the valve to iopen to permit spill upon the development -of any jet interrupting Apressure in the overflow chambervbeyond the capacity of the relief passage, Vand to automatically release the holding pressure upon the overilow valve upon jet interruption.

Another object of the invention is to provide means for either manually or automatically closing the overflow valve of an injector at a determinedpressure, lthe overflow Valve yieldable 'to permit overilow by counter pressure developed in the overilow chamber controlled by said valve.

Another object is to provide a relief passage for the overflow chamber, in communication with the water intake passage ofl the injector, -to escape and prevent jet interrupting fluid accumulation in theloverflow chamber.

@Another object of the invention is to provide means for maintaining the overflow valve closed, and for removing any accumulated water and/or steam from the overflow chamber through a recirculating `passage back to the water supply.

Various other features and advantages of the invention will be more fully apparent from adescription of-the accompanying drawing, in which:

Figure 1 is a central vertical sectional view of an injector, embodying the improved overilow valve together with a valved back flow passage for `relieving pressure in the overiiow chamber.

Figure 2 isa central Vertical section taken Aat right angles to Figure 1, further illustrating the injector structure, and embodying a modified relief passage in the form of an open duct in communication with the overow chamber andthe water intake passage.

yFigure 3 is a modied form of overflow valve. Referring to the drawing, `I indicates the injector body having a steam inlet passage 2 at one end thereof. The body is provided with an opening to the steam inlet passage coaxially with the injector nozzles, sealed by a bolted cap or closure 3. A steam .intake nozle 4 `is screwthreaded into a partition wall 5 of the body, the nozzle communicating with the steam inlet passage and `carrying a jet nozzle 6 within a water intake chamber l. 8, El, and l0 indicate the condensinglor combining nozzles in coaxial arrangement andinadvance of a delivery nozzle l I.

The nozzle arrangement follows a conventional form and practice, with the delivery nozzle extending into a discharge passage I2, the passage in the present form extending at an angle to the body, and has interposed therein a delivery check maintain adetermined holding pressure on the 55 valve lf3.

The water intake chamber I communicates with an intake port I4 controlled by a disc valve I5, rotatively mounted upon one end of a stem or spindle IE. The stem has a screw-threaded engagement through a bonnet I1, screw-threaded into an opening in the body, and the stem extends beyond the bonnet and at its outer end is provided with a swivel joint I8 for making a connection with the valve actuating means extending remotely therefrom.

An overflow opening I9 laterally of the nozzle 8, and overflow openings 22 as intermediate of the nozzles 8, 9, I9, and II, communicate with the overflow chamber 23 surrounding the nozzles, and closed by a check valve 24 within an overflow casing 25 as part of the injector body. The check valve 24 when open permits water to be discharged through the water passages 25 and 25a in the overflow casing and through a conduit in connection therewith to the atmosphere.

The overflow valve 24 is preferably yieldingly urged against its seat by a spring 2'I engaged about a stud or shank 28 projecting from the upper side of the overflow valve 24. One end of the spring bears against the rear side of the overflow valve, and its opposite end against and housed within the under side of a valve or plunger 29, guidingly and slidingly mounted within the housing 30 secured to the overflow casing 25. Y

The valve 29 is supported in a predetermined position by the spring 21. A bonnet 3I is secured on the upper end of the valve housing 30 and is traversed by a stem 32 having a screw-threaded engagement with the bonnet for vertical adjustment oi the stem. The bonnet is provided with a stufng box for holding the packing 33 about the stem. The stem provides means for manually closing the overflow valve, and is adapted to receive connections for operation from a remote point. The valve housing 30 provides a chamber 34 in communication with the discharge chamber I2 through a pipe or passage 35.

The pressure from the discharge chamber I2 acts upon the valve 29, forcing the same to its seat 36, thereby preventing any leak from the chamber 34 to the atmosphere. The valve 29 when seated compresses the spring 21 holding the overflow Valve 24 in a closed position, preventing the accumulation of hot water and steam from spilling or overflowing to the atmosphere during the operation of the injector.

In a starting operation of the injector, an cutlet must be provided for the escape of water and steam from the injector prior to the establishment of a jet of sufficient velocity and pressure to force the water into the boiler. The purpose of the overflow valve is to provide an outlet for the surplus water which accumulates in the overflow chamber after the water and steam Valves are opened, and during the formation of the jet, and also to prevent atmospheric air from entering the overflow chamber after the jet has formed and the injector has attained its maximum delivery. In the starting period, the pressure of the combined water and steam within the overflow chamber 23 is sufficient to lift the check valve 24 for the escape or discharge of the water and steam to the atmosphere through the drain pipe connecting with the overflow casing.

The pressure existing in the overflow chamber 23 is also present in the discharge chamber I2, and is communicated to the Valve chamber 24 Iii) of the overflow valve through the passage or conduit 35, and under such condition, the pressure and volume is never of an intensity sufficient to move the valve 29 to overcome the resistance of the spring 21 to close the check valve 24, the latter being free to open to spill or overflow the combined water and steam prior to the formation of the jet within the injector.

Upon the establishment of a jet and pressure sufficient to force the water into the boiler, the pressure in the overflow chamber 23 is reduced and the pressure in the discharge chamber or passage I2 is increased and correspondingly in the valve chamber 34, to depress the Valve 29 to its seat against the resistance of the spring 2l', and thereby imparting a pressure on the overflow valve 24 to hold it closed. This automatic closure of the overflow valve 24 relieves the operator from manually closing the same.

The overflow valve remains closed as long as the injector is functioning properly. In one of the best operating conditions, a vacuum exists in the overflow chamber, and the overflow valve will remain closed. When the injector encounters operating conditions such as can no longer make its maximum delivery, a change occurs in the overflow chamber as the percentage not delivered will accumulate in the overflow chamber and the Vacuum will decrease. The operating conditions can be such that the percentage of the total water and steam going to the injector, which the injector failed to deliver, can become so great as to create a pressure in the overflow chamber of suicient intensity to open the overflow valve and permit the non-delivery water to escape to the atmosphere.

Varying conditions of operation are encountered, particularly in locomotive service, which may cause an increase in pressure in the overflow -chamber 23 sufficient to lift the overflow valve 24. Thus provision is made to reduce the pressure in said overflow chamber 23. An abnormal increase in pressure in the overflow chamber may be due to an accumulation therein of hot water and steam, and in accordance with the present improvement, this can be avoided by the provision of a relief passage interconnecting the overflow chamber and the water intake passage or chamber 'I for the escape and flow of hot water or steam from said overflow chamber back to the point of water supply origin.

An embodiment of a most simple form of relief is illustrated in Figure 2, consisting of a constantly open duct 31, which may be formed either within the body of the injector, or as al conduit connecting the two chambers, and through which the accumulated hot water and steam can be transported to reduce or eliminate the development of a jet disrupting pressure in the overilow chamber. In the modified form of relief passage, as illustrated in Figure l, applicable as an attachment exterior of the injector body, if desired the passage is equipped with a pressure actuated valve, closing toward the intake chamber.

The modified back-flow installation is preferably made by connecting one end of a pipe elbow fitting 38 to a closure plug 39, with which the injector body is provided leading into the overflow chamber 23. The opposite end of the pipe elbow fitting is fixed into one end of a valve body 45 as screw-threaded into a reducer 4I secured into one end of the valve body. The opposite end of the valve body 49 connects with a second pipe elbow fitting 42 fl-Xed to and leading into the intakechamber s1 'of the injector. Y

Aslide valve '43, having /a tubular hub portion, is slidably mounted within the valve body, with the head end of the valve in a normal or open position abutting vor `resting upon an inner tubular extension of the reducer. The hub portions' of both the valve and reducer are provided withlaterali-apertures or ports 44 to interconnect the sections of the back-flow passage when the valve is in anopen position, and to control communication between said overflow and water intake chambers.

The valve under normal operation of the inje'ctor provides a free passage for the accumulated hot water and steam or fluid `from chamber 23 to water intake chamber 1, and closes off any flow of high pressure steam from the overflow chamber resulting from a disruption of the jet. When the valve is open, the fluid is free to pass from the overflow chamber through the lateral ports in the sleeve extensions or hubs of the reducer and of the valve, the ports through the valve being uncovered and open to the valve chamber, allowing the transported fluid to be intermixed with the water supply administered to the injector.

Should jet interruption however occur, Yfilling the overflow-chamber with high pressure steam, and due to the restrictions offered by the apertures in the hub of the reducer, the high pressure steam will force the valve to its closed position sealing its `aperture or ports preventing the escape of `pressure to the water intake chamber. Closing of the emergency back-flow valve, preventing the escape of high pressure into the water intake chamber, results in immediate opening of the overflow valveto allow the high pressure steam to `issue from the injector to the atmosphere until the jet is reestablished or the injector is stopped,

Immediately upon disruption of the jet, the pressure in the overflow and discharge chambers will become equalized, and as the area of the overflow valve 24 exceeds the area of the Valve `29, the force on the greater area of the overflow valve will prevail to open the overflow valve providing for the escape to the atmosphere of the pressure in the overow chamber 23.

The manually actuated stem 32 of the overflow valve provides means for manually closing the overflow valve and forcibly holding it to its seat. Upon feeding the stem downwardly or inwardly, the pressure actuated valve 29 is moved and held to its seat, compressing the spring 21 to forcibly hold the overflow valve 24 to its seat.

In the modified form of control for the overflow valve 24, shown in Figure 3, the plunger valve 29 is ineffective upon positively manually closing the overflow valve by means of the control stem 32. In this instance, "the valve 29 is slidably mounted within a cylindrical head 45 of the stem 32 traversing the bonnet 46. The cylindrical head toward its upper end has an annular channel 41 in its periphery in communication through a port 48 in the bonnet, with the conduit 35 connecting with the discharge chamber E2. The wall of the head 45 is provided with a plurality of ports connecting the channel 41 with the chamber 49 of the head. lWhen the pressure in said chamber 49 is of sufficient intensity to depress the valve 29 against the tension of the spring B1, it will hold the overflow valve 24 closed under a determined pressure. The valve upon being depressed engages an annular seat or shoulder 53 1in the bore of the bonnet, when the stem is Ain its neutral or fully opened position.

When the `manual control is in its open or neutral position, as indicated in the drawing, the

Y operation of the valve 29 is substantially as heretofore described. The starting of the injector will exert a pressure on the valve 2B, forcing it to its seat in the head of the Stem, compressing the spring, which in turn holds the overflow valve 24 closed `under the predetermined pressure of the spring. When the stem 32 for manual control is fed downwardly, the cylindrical head 45 is moved in direct contact with the overflow valve depressing the same against its seat and rendering the valve 29 ineffective. The head 45 in moving downwardly interrupts the communication of the channel 41 with the port 48, cutting off the pressure to its chamber 45, The manual closure of the overflow valve primarily is to seal` against fluid escape when the injector is used as a heater.

The control of the overflow valve, either automatically or mechanically, together with the relief passage for establishing communication between the intake and overflow chamber, materially improves the efciency and operation of the injector, increasing the range and utility and operation with higher feed water temperatures than has heretofore been possible, and will also increase the life of the injector nozzles considerably.

` Any effective reduction of the fluid pressure in the delivery chamber insuiilcient to resist the eX- panding pressure of the springr 21 opens the chamber 34- to the atmosphere, and thereby immediately releases the holding pressure upon the overflow valve, so that it will be free to function in a normal manner.

It is a prevailing practice to condemn an injector for spilling regardless of the cause. An injector in perfect adjustment will spill under certain conditions which constitutes its operating limits, and the` present improvement increases Or widens these limits.

Having described our invention, we claim:

1. In an actuating means for the overflow valve of an injector, a casing have a fluid pressure connection to the delivery chamber of the injector and an opening to the atmosphere, a pressure actuated plunger for closing said opening, an overflow valve to control the escape of fluid to the atmosphere from the overflow chamber of the injector, and yielding means interposed between said pressure actuated plunger and overflow valve to close said overflow valve at a determined pressure when said plunger is depressed, and permit the overflow valve to open by a prevailing counter pressure in the overflow chamber of the injector.

2. In an actuating means for the overflow valve of an injector, a casing providing a chamber having a non-controlled fluid pressure connection to the delivery chamber of the injector, a pressure actuated plunger in said casing chamber, an `overflow valve to control the escape of fluid to the atmosphere from the overflow chamber of the injector, and yielding means interposed between said pressure actuated plunger and overflow valve to close said overflow valve at a determined pressure when said plunger is depressed, and permit the overflow valve to open by a prevailing counter pressure from the overflow chamber of the injector.

3. In an actuating means for the overiiow valve of an injector, a casing having a luid pressure connection to the delivery chamber of the injector` and opening to the atmosphere, a pressure actuated plunger for `closing said opening, an overilow valve to control the escape of uid to the atmosphere from the overow chamber of the injector, yielding means interposed between said pressure actuated plunger and overow valve to close said overflow valve at a determined pressure when said plunger is depressed, and permit the overflow valve to open by a prevailing counter pressure in the overilow chamber of the injector, and manually operable means for depressing the plunger to close the overflow valve.

4. An actuating mechanism for the overflow of an injector, comprising: an overflow valve to control the escape of fluid to the atmosphere from the overow chamber of the injector, a bonnet for supporting the actuating mechanism for the overow valve and providing a chamber having an opening to the atmosphere, the chamber in communication with the delivery chamber of the injector, a pressure actuated plunger within said bonnet for closing said chamber opening, yielding means interposed between said pressure actuated plunger and overflow valve to close the overflow valve at a determined pressure when the plunger is depressed and permit the overflow valve to lopen at a prevailing counterpressure in the overflow chamber of the injector, and a screw operated stem movable within said bonnet for positively closing said ove'row valve.

5. An actuating mechanism for the overflow valve of an injector, comprising: an overflow valve to control the escape of fluid to the atmosphere from the overflow chamber of the injector, a bonnet for supporting the actuating mechanism for the overflow valve and providing a chamber having an opening to the atmosphere, the chamber in communication with the delivery chamber of the injector, a pressure actuated plunger within said bonnet lfor closing said chamber opening, yielding means interposed between said pressure actuated plunger and overilow Valve to close the overow valve at a determined pressure when the plunger is depressed and permit the overow valve to open at a prevailing counter-pressure in the overow chamber of the injector, and a stem movable within said bonnet for positively closing said overflow valve, and directly engageable therewith.

6. An actuating mechanism for the overflow valve of an injector, comprising: an overflow valve to control the escape of fluid to the atmosphere from the overow chamber of the injector, a bonnet for supporting the actuating mechanism for the overflow valve, a stem movable within said bonnet and engageable with said overflow valve to positively close the same, and having a cylindrical head providing a chamber having an opening to the atmosphere, the chamber in communication with the delivery chamber of the injector, a pressure actuated plunger within said cylindrical head of the stem for closing said chamber opening, yielding means interposed between said pressure actuated plunger and overflow valve to close the overow valve at a determined pressure when the plunger is depressed and permit the overflow valve to open a prevailing counter-pressure in the overflow chamber of the injector.

HENRY A. BOSONEITO. W. EARL SNYDER.

Images