US2051347A - Locomotive throttle valve - Google Patents

Description

A 1936* c. .1. SCUDDERET AL LOCOMOTIVE THROTTLE VALVE 5 Shees.Sheet 1 Filed Jan. 18, 1954 w/ T j Z w Charles 5ouader;

II} I Aug. 18, 1936. C J SCUDDER ET AL 2,051,347

LOCOMOTIVE THROTTLE VALVE Filed Jan. 18, 1934 5 Sheets-Sheet 2 jOa ammtom Charles .l ficzzddelg Aug. 18, 1936. c, J SCUDDER -f' L 2,051,347

LOCOMOTIVE THROTTLE VALVE Filed Jan. 18, 1934 3 Sheets-Sheet 3 Snow wows Charles 1.504421%)", 86 5- 5 RIIEZQZ V attuned Patented Aug. 18, 1936 PATENT OFFIQE 'LOCOMOTIVE THROTTLE VALVE Charles J. Scudder and Samuel S. RiegeL' Scranton, Pa.

' Application January 18, 1934, Serial No. 707,212

6 Claims.

This invention relates to throttle valves for steam locomotives. The pricipal object of the invention is to provide a throttle valve that is fully balanced so as to be most easily operated for steam shutoff and control and which, when closed, is loaded with full steam pressure over the entire area of its shutoff and guiding head. In accordance with our invention, the provisions for balancing the valve and for guiding the same are so disposed and located as to be entirely out of the way of the steam passage so that the flow of steam when the valve is opened is unobstructed by any obstacles or impediments, such as ribs, pockets, and entanglements, which in ordinary 5 practice, present barriers to the steam flow and cause eddy movements thereof. A further object is to provide a valve equipped with provision for a graduated opening to steam flow so that a close and fine graduation thereof may be secured. This result is obtained by providing an element in the form of a graduating sleeve having a limited range of movement separate from the body of the valve and restricting the inflow of steam until such sleeve is raised from its seat. A still further object is to provide means in connection with the balancing device for admitting a limited inflow of steam to the steam chest upon the opening of the mitre and pilot valve so as to preliminarily fill and warm the steam pipes and o steam chest and avoid shock to these parts. A still further object is to provide a light, strong and symmetrical valve that, in general, conforms to standard locomotive throttle valve practice and is capable of being easily assembled and 5 taken apart when necessary.

The foregoing and other objects and advantages of the invention will be better understood from the following detailed description taken in connection with the accompanying drawings,

40 and the distinctive features of novelty will be thereafter pointed out in the appended claims.

Referring to the drawings Figure 1 is a vertical section of a valve structure embodying the invention, the right half of 45 said figure showing the moving parts with the valve closed and the left-hand side showing the moving parts with the valve partially opened;

Figure 1a is a fragmentary sectional detail showing a modified form of the invention;

Figure 2 is a vertical section partly in elevation showing a modified form of the valve adapted for use as a dome throttle valve; and,

Figure 3 is a partial vertical sectional view longitudinally of the front end of a locomotive 55 equipped with dome throttle and smoke-box throttle valves embodying the invention.

It! indicates a valve body equipped with one or two inlet supply channels I I, and one or two outlets IZ as the installation may require. l3 indi- 60 oates a valve seat fitted in an opening of the body In and M denotes a sleeve set into the upper part of the body having doWnwardly-extendingguide members l5 which rest over the top of the valve seat l3 and are adapted to guide the valve in its opening movement. This sleeve is equipped with an inwardly extending flange rim or stop Ma. to limit the opening movement of the valve. IS indicates the valve body having an upper head IGa constituting the valve proper and a lower head l6b bearing the balancing element. The intermediate stem of the valve 16 is hollow and has ports I6 near the upper end thereof to permit limited flow of steam as later explained. The head Ilia is equipped with vertically extending recesses 16d, in which lugs Ila borne by a sleeve ll have limited movement. The sleeve l l is split circumferentially to expand over head lEa. for assembly and is fitted to slide vertically of the head lfia and is closely guided by the guides l5. When in lowered position the sleeve ll seats upon the 20 valve seat I3, and when the head ltd is in lowered position a preferably beveled seating surface thereof seats on a preferably beveled surface I60 of the seat l3. The sleeve I! is equipped with a series of holes l'lb near the bottom thereof of substantial extent in the line of valve movement, the aggregate area of these holes being sufficient to permit a substantial, but still materially restricted flow of steam therethrough. Thus, when the valve head Mia. is seated upon the seating surface ltc the valve is fully closedas shown at the right in Figure 1. An initial opening of the valve, as seen at the left in Figure 1, will lift said head off of the seat I60 and permit inflow of the steam through the holes Hb in restricted volume and gradually increasing as the holes are more fully uncovered by the valve head Ilia, the sleeve I! being still seated upon the valve seat. A further opening movement of the valve causes the lugs Ila to engage the bottoms of the slots ltd and thus lift the sleeve ll permitting inflow of the steam in full volume, according to the degree the sleeve is raised. In Figure 1d we show a modified form wherein the valve head lfilla is equipped with two steam graduatingsleeves I10, 219, split to permit assembly similarly as the sleeve ll, these sleeves having ports I'lta, H911, and having lost motion with respect to each other and also with respect to the head lfiiia. similarly as already described, thus permitting a still closer graduation of the steam inlet upon the opening movement of the valve. It? indicates the operating stem of the valve which may be actuated by any usual or suitable operating connections, it being understood that the top of the valve body is enclosed as seen at It in Fig. 3 and with suitable stuffing boxes for the operating means to prevent escape of the pressure steam. The lower end of this stem is equipped with a collar 19 which is adapted to engage shoulders 20 on the valve body 60 'termediate the hollow interior thereof.

this position of the stem being as indicated, at the right in Figure 1. The preliminary upward movement of the stern I 8 lifts the pilot valve 2| o-fi its seat as seen at the left in Figure 1, admitting live steam downward through a sleeve IIie, whichextends downward in the valve stem or body in- The steam is thus directed underneath a plunger head 23 which is fixed at the lower end of the valve head I612. The plunger head 23 is equipped with suitable packing 23a and operates in a cylinder cup 24 which is'mounted in a cavity provided therefor in a bottom member 25 secured to or forming a part of the valve body. The cylinder 24 is preferably of dissimilar metal from the bottom body casting 25 to constitute a wear bushing in which the plunger 23 which constitutes the balancing head operates. In the described movement of the stem I8 it is guided with respect to the upper portion and head IBa of the valve by guide ribs I6 1 extending inwardly from said head and affording guide bearing surfaces for the stem. The upper surface of the head 23 is provided with a series of spaced-apart guiding lugs 26 around its periphery. These are for the purpose of engaging the inner lower beveled surface of the valve seat I3 to guide the same to itsv seat when the parts are lowered into position, it being understood that the assemblage of parts is from above. The open: ing of the pilot valve thus furnishes live steam which is directed underneath the balancing head 7 23 to balance the valve and a portion of such steam also passesup between the sleeve |6e and a v the walls of the valve stem cavity, and thence outward through the ports I 6f. This steam thus fills and warms the steam pipes and steam chest avoiding shock to these parts and also provides in a measure. suflicient steam flow for'drifting purposes. The further raising of the stem l8 permits limited and gradually increasing inflow of steam through the holes III) as the valve is, progressively lifted and the final lifting movement raisesthe sleeve |'I permitting a full inflow of steam when it is lifted torits fullest extent.

It is to be particularly observed that the described construction provides means for fully balancing the valve so that it is most easily operated, and that the balancing means is located V the top, and by the balancing plunger 23'at the bottom. While the plunger 23 has been described as operating in a bushing cup fitted in the base 25, it is to be understood that this bushing may be omitted if desired and the head 23 fitted directly in the cylindrical cavity of the base 25.

It is to be noted that the described construction provides for most complete control of steam flow to the cylinders. The initial movement of the stem I8 by admitting steam through the pilot valve 2| underneath the head 23 at once balances the valve so that it may be most easily operated and the same inflow of steam passing out through the ports l6 initially fills and warms the chambers and steamichest, filling these very smoothly and avoiding shocks and bursting strains on the parts filled-it will be appreciated that when a quick and heavy rush of steam is admitted therein according to customary practice, a considerable strain is set up in these parts, while the limited graduated flow provided by our device avoids such severe and bursting shocks as are encountered in the usual throttle valve arrangement. The described construction and arrangement of the sleeve I! with its lost-motion connection with respect to the head of the valve serves the two-fold purpose of accurately and very finely graduating the steam flow for a limited flow in starting the locomotive, and also serves to quickly arrest the locomotive from slipping and to avoid a complete shutoff.

The described form of the invention is one well adapted to be and herein shown as mounted in the front end or smoke-box of the locomotive to control the flow of steam from the dry superheater header to the steam chest. The invention is also well adapted for use as a steam dome throttle, and in Figure 2 we show a simplified form of the invention adapted for use as a dome throttle valve. body of the valve havinga. depending portion |00a in which the balancing device is mounted and on which the operating connections are fitted. The inflow of steam is in this form through the open top of the valve body and the outflow is through the passage I20. I30 indicates the valve seat and I40 the slotted guide sleeve in the lower portion of which the head |a of the valve I60 is slidably fitted. Since, for a valve in this location and to be used in conjunction with the form first described a close regulation of the steam flow is not necessary-there is no separate steam graduating sleeve shown in this form. I 80 indicates the operating stem having mounted thereon the pilot valve 2|0, which fits a seat "220 controlling steam flow downward through the hollow stem of the valve. 230 indicates thebalancing head fixed at the lower end of the valve stem and fitting the cylinder 240 formed in the bottom'of the valve body. It is to be noted that in this form also, the balancing cylinder 240 is below and out of the way of the path of steam flow so that'a maximum unobstructed area for the flow of the steam is pro- 7 vided. As in the first described form, the initial movement of the stem opens the pilot valve and provides balancing pressure underneath the head 230 so that the valve may be most easily operated. 26 indicates a cross bar at the top of the stem I80 having links 21 secured at its ends by pins 28, these links extending downward at each side of the valve body and engaging arms 29 of bell-crank levers pivoted to one side" of the valve body at 30. An operating link 3| extends to usual or suitable operating connections for operating the valve.

In Figure 3 is shown, conventionally, a preferred and practicable arrangement of a dome throttle in connection with a smoke-box throttle valve as embodied in our invention. 32 indicates, generally, the forward portion of the body of a locomotive, 33 being the smoke-stack and 34,

In this form- I00 indicates the generally, the superheater header arrangement partment of the superheater header, thenceafter being superheated by the superheater units, it passes through pipe H and inlet connection H to the smoke-box throttle valve I9 and thence through discharge connections I! and pipes I2 to the steam chest of the locomotive. This provision of two cooperative throttle valves as set forth is of value and importance for the reason that if a dome throttle only were employed, when the steam is shut off from the cylinders, all of the steam must be exhausted from the throttle so located to the cylinder at every shutdown, This involves a great loss of steam and also, since the parts must be refilled with steam, without the use of a separate superheater throttle, there would be no superheat in the steam at the start; in other words, there would be a loss of about fifty cubic feet of steam at every shutdown which would do no useful work. A further advantage in the use of a separate superheater throttle along with the dome throttle is that, should anything go wrong with the superheater throttle requiring that it be opened and repaired, the dome throttle can be closed, the steam allowed to escape between it and the superheater throttle, and the superheater throttle then allowed to cool off so that it can be accessible for repair. Without the use of the dome throttle it is impossible to open and examine the superheater throttle when necessary while the engine is under steam. The use of the superheater throttle avoids this great waste of steam, permits the steam to be superheated and remain superheated constantly, so that on starting the engine superheated steam is immediately available, and the engineer is able to quiet his engine against slipping almost instantly. With the dome throttle alone, slipping would occur until the full force of the steam remaining between the dome throttle and the cylinders had spent its energy sufficiently to overcome slippage; thus an engine with a superheater throttle is relatively free from slipping as compared with one controlled by a dome throttle alone.

We are aware that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and we therefore desire the present embodiment to be considered in all respects as illustrative and not restrictive, reference being had to the appended claims, rather than to the foregoing description to indicate the scope of the invention.

Having described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A steam throttle valve comprising a body having inlet and outlet passages, a reciprocating valve controlling communication between said passages and normally loaded with the full steam pressure when closed, said valve having means for completely balancing the same for opening located substantially out of the way of the flowing steam, relatively remote from said inlet passage and in proximity to said outlet passage, a pilot valve for admitting balancing steam at the initial opening movement and means for directing aportion of the steam admitted by said pilot valve to initially warm and fill the outlet passage and the steam chest of the locomotive, said last named means arranged to keep the connection to the outlet passage open throughout the opening movement of the pilot valve to provide for drifting.

2. A steam throttle valve for locomotives comprising a body having inlet and outlet passages,

a reciprocating valve having a head mounted to control communication between said passages, said valve having a hollow stem with a balancing piston at its extremity located out of the path of flowing steam, and a pilot valve mounted to open 5 on initial valve opening movement to admit balancing steam pressure, there being connections to permit a portion of the steam so admitted in the opening and also the fully opened positions of the pilot valve to enter the outlet passage to 10 warm and fill the same, and to provide for drifting.

3. A steam throttle valve for locomotives comprising a body having inlet and outlet passages,

a slotted guide bushing mounted in the inlet pasl5 sage with a balancing piston mounted at the lower end thereof, a cylinder inwhich said piston operates, an operating member for said valve extending through said stem, bearing a pilot valve to admit steam pressure through said hollow stem for initially balancing the valve, said stem having ports opening to the outlet passage in the upper part of the hollow stem, and a sleeve extending downward of the hollow stem and adapted to divert balancing steam upward through said ports to initially Warm and fill the outlet passage and connections to the steam chest.

4. A steam throttle valve for locomotives comprising a hollow valve stem having a head at its upper end fitted to engage a valve seat and having a balancing piston mounted on its lower end, an

operating rod extending through the hollow stem of said valve equipped with a pilot valve to control passage through said stem, said rod having means for engaging the valve to lift the same after a preliminary lifting movement to lift the pilot valve from its seat, there being a sleeve extending downward through the hollow interior of said stem and ports opening outward from the upper portion of said hollow interior for the purpose stated.

5. A steam throttle valve device comprising a body having inlet and outlet passages, a valve seat mounted between said passages, a slotted guide sleeve fitted from above in said inlet passage and resting upon said valve seat, and a valve having a head engaging said seat and guided by said sleeve, said valve having a depending stem with a balancing piston fixed at its lower end, said piston having lugs on its upper surface adapted to engage and center said valve seat, the

valve seat having a tapering lower area to engage said lugs for insertion and removal of said seat.

6. A steam throttle valve for locomotives comprising a valve seat, a reciprocating valve to engage said seat and a plurality of sleeves fitted respectively to said valve and to each other with a lost-motion connection, each of said sleeves having openings in its lower portion and each adapted to engage an area of said valve seat outward from the seat of the valve proper, said openings being normally in register with one another and permitting graduated limited steam flow upon initial opening movement of the valve and gradually freer steam flow as the valve is further lifted.

CHARLES J. SCUDDER. SAMUEL S. RIEGEL.

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