US541605A

US541605A - Engine-valve

Info

Publication number: US541605A
Authority: US
Publication date: 1895-06-25
Anticipated expiration: 1912-06-25

Description

3 Sheets-Sheet 1. H. R. PAY. ENGINE VALVE.

Patented June 25, 1895.

5 5 B 5 m Mr .4 m 5 I v NW1 m .E Y T V w 2 w m H w w Y. I 1 5 "M1,: .HJ% H. i I W oo 3 3 1 m k M m z l 5 7 m w 1 r 4 w w m W. 1 m a M m mt 5 3 5 m L w (No Model.)

WITNESSES:

I "-j/ W D .(No Model.) 3 Sheets-Sheet 3.

H. R. PAY.

.ENGI-NB VALVE. No. 541,605. Patented June 25, 1895.

. 39 c C i Mi {p 26% 4 2'5 32: F. -B 5 7 [TE-.7; I WITNESSES;

INVENTEIR:

UNLrTE STATES .ATENT HENRY ROLAND FAY, OF BOSTON, MASSACHUSETTS.

ENGINE-VALVE.

SPECIFICATION forming part of Letters Patent No. 541,605, dated June 25, 1895 Application filed March 23, 1895.

To all whom it may concern:

Be'it known that I, HENRY ROLAND FAY, a citizen of the United States, residing at Boston, in the county of Sufiolk and Commonwealth of Massachusetts, have invented certain new and useful Improvements in Engine- Valves, of which the following is a specifica tion.

My invention relates to improvements in to engine-valves, and it is designed as an improvement, in part, on my engine valve as secured to me by United States Letters Patent No. 494,194, dated March-28, 1893.

It has for its object the special construc [5 tionand arrangement of the extra cylinder and valve ports. In an engine-valve, the greater the outside lap, the wider (as a rule) may be the groove, or extra valve port. In most locomotives, the outside lap is only suf- 2o ficient to permit the construction of agroov'e or extra valve port of about one half inch in width having a limited cross-sectional area. Therefore, when it is desired to have the extra cylinder ports of considerable .crosssectional area, it is essential, that they and the grooves, or extra valve ports, should be constructed and arranged, substantially as shown in the drawings and as hereinafter described, in order that the, relieved compression may 0 pass freely from the admission port, through the groove, or extra valve port, into and through the extra cylinder ports, and then into the bore of the cylinder.

It also has for its object, not only the relieving of compression and counter-pressure within engine cylinders; but also the increasing of the steam admission port area, especially on short points of cut-off and at the commencement of the opening of a steam admission port by its valve. This increase of admission port area is arrived at independently of the action of the so called Fay ports or the extra cylinder and valve ports. Nevertheless, by reason of adapting the valve to the extra cylinderand valve ports, I am thereby enabled to readily construct and operate the extra steam admission ports.

Figure 1 is a full plan view of a locomotivecylinder with steam-chest and valve removed in order to show the extra cylinder and the extra admission ports. Fig. 2 is a vertical sectional view on line A B of Fig. 1 with the being shown by arrows.

Serial No. 542,982. (In model.)

valve in section, the direction of the movement-of the valve and piston being indicated by means of arrow, illustrating by means of arrows steam admission through admission and extra admission ports. Fig. 3 is a vertical central sectional view of the cylinder and. valve, showing the relative positions of piston and valve at short points of cut-ofif, the direction of travel of both piston and valve being indicated by means of arrows. Fig. 4 is a vertical central sectional view of the cylinder and valve, showing the relative positions of both piston and valve at point of release, the direction of travel of both piston and valve being indicated by means of arrows, the path of the relieved compression Fig. 5 is an inverted plan of the valve, and Fig. 6 is a sectional view of the valve on line C D of Fig. 5 and a portion of the valve-seat, the path of the relieved compression from the admission-ports through one of the extra valve-ports into one set of the extra. cylinder-ports being indicated by arrows, Fig. 7 is' a cross-sectionalview of the cylinder, showing by 'means of dotted lines the course of the extra cylinder-ports from the valve-seat to the cylinder-bore.

In the drawings the locomotive cylinder 10, is provided with the following: Front head 11; back head 12; piston 13, having piston rod 14; and exhaust port 15, all of whichare of ordinary construction and arrangement. The cylinder is also provided with the following: Valve seat 16;

front admission ports

17 and 18, which are separated by means of the front admission port bridge 19;

back admissions ports

20 and 21, which are separated by means of the back admission port bridge 22. These back admission ports may be united into one back admission port if desired, in the manner represented by dotted lines 23, in Fig. 1. So also, may the front admission ports be united into one front admission port. The set of front extra cylinder ports, comprising the

ports

24, 25, and-26', start from the valve seat 16, between the admission ports and the exhaust port, and extend to the cylinder bore; and in the same manner, the back set of the extra cylinder ports, comprising the

ports

27, 28, and 29, start from the valve seat 16, between the back admission ports and exhaust port, and enter the cylin- ICO mission ports, comprising the

ports

33, 34,

and 35, start at a point on the valve'seat, near the back ad mission ports, and extend to the back admission port or

ports

20 and 21,.without entering into or interfering with, the back set of extra cylinder ports.

The valve 36, having the valve rod 37, is"

provided with the following: Exhaust cavity 38; front groove, or extra valve port 39; back groove, or extra valve port 40; the .front set of lugs, comprising the

lugs

41, 42, and 43; the back setof lugs, comprising the

lugs

44, 45, and 46; and the exhaust cavity bridge 47.

The exhaust cavity bridge 47 is madetfor the purpose of preventing the blowing ofthe steam from the center extracylinder ports into the exhaust .port and also for protecting the valve seat.

In applying my invention, I haveevolved the following general formulae, by the observance of which, my device maybe understandingly applied. These formulae must of course be varied more or less in order to best adapt my invention to the various kinds and styles of engines.

First. One half of stroke of piston uni-nus cutoff, expressed in inches travel of piston,

minus distance between center oitpiston and center of packing ring (or if only one wide packing ring, minus one half of Width of Wide ring lessone half inch) equals distance between center of extra cylinder port at its point of entrance into cylinder bore from vertical center line of cylinder.

Second. The distance from inner edge of admission port to vertical center line of cylinder and valve seat, minus one half ofdiam' eter of extra cylinder port, equals distance between the center of extra cylinder port at its starting point at valve seat and vertical center line of cylinder and valve seat. Each extra cylinderport at starting pointon valve seat is to be squared out on aline with inner edge of admission port. The diameter of each extra cylinder port in side wall is to be as .greatas possible leaving at least three-sixteenths of an inch stock on side wall, each side of extra cylinder port, at starting point.

Third. The distance between squared inner edges of end cavities of groove is to be equal to the distance between inner edges of admission ports, plus twice inside lap of valve (or minus twice the inside clearance of valve). (The squared inner edge of each end cavity should reach extra cylinder port when exhaust takes place on opposite end.)

Fourth. The distance from outside edge of groove to outside edge of valve must be greater than the width of admission port.

Fifth. The width of groove in valve must be less than-the distance from line of exhaust port to extra cylinder port in valve seat.

Sixth. The depth of the gooove should be less at its center than at its sides.

Seventh. Area of groove should be greater than the area of the extra cylinder port with which it connects.

Eighth. Each lug on valve is to have one eighth inch outside lap over extra cylinder port when the valve is at its full travel.

Ninth. Extra admission ports to open at the same time as main admission port.

The operation of my device is follows: In Fig. 2, the piston is shown at the beginning of its stroke, and the valve is represented as admitting steam into the back end of the cylinder, the direction of travel of bot-h piston and valve being indicated by means of arrows, and it will be observed that steam is being admitted, as indicated by arrows, into the back end of the cylinder through

admission ports

20 and 21, and the

extra admission ports

33, 34, and 35. It will be noticed that a greater area, at short points of cut-off, or during the beginning of steam admission, will be obtained by the combined area presented at the earlyopening of the admission and the extra admission ports, than would be obtain ed under the same early opening, it there were no extra admission ports and no admission port bridge. Therefore, under these condi- .tions, a higher initial pressure would be obtained in the cyl'inderby the use of my device, than would be obtained in the same cylinder not provided with my device. The back set of

lugs

44, 45, and 40, are so made that they will prevent. respectively, the uncovering of the

extra cylinder ports

27, 28, and 29, when the valve is at its ifllll travel. The

extra admission ports

33, 34, and 35, are so located, that they will be uncovered or opened by the

lugs

44, 45, and 46, respectively, at the same instant, that the

admission ports

20 and 21, are uncovered or opened by the valve.

In Fig. 3, the piston and valve are represented in their correct relative positions at pointof cut-off, thedirection of travel of both piston and valve, being indicated by arrows. It will be observed, that the back set of extra cylinder ports, 27, 28, and 29, have their point of entrance into the cylinder, at such a point, that they will be covered by the piston at short points of cutoff, this construction. being to prevent the blowing over, at short points of cut-off, of the steam admission into the cylinder on the other or opposite side of the piston.

In Fig. 4 the piston and valve are represented in their correct relative positions at pointof release, the direction of travel of both piston and valve being indicated by arrows, the path of the released compression, being represented by means of arrows, from the front end of the cylinder, through

admission ports

17 and 18 into the extra valve port and from this extra valve port 39 through the

extra cylinder ports

24, 25, and 26 (in the manner as shown by arrows in Fig. 6) into the back end of the cylinder on the opposite side of the piston, from which it passes into the exhaust cavity 38 and exhaust port 15 through

admission ports

20 and 21. v

It will be noticed, referring particularly to Fig. 6, that by reason of the construction and arrangement of the extra cylinder and valve ports I am able to use an extra valve port having a very small average cross-sectional area, compared with the area of the set of extra cylinder ports, through which the relieved compression may freely pass, in four directions as indicated by arrows, without impairing the operating efficiency of the device, and at the same time, by reason of thepeculiar construction of the extra cylinder port, the Valve is not materially weakened by the'cutting of the groove, whereas the valve would be materially weakened if the cross-sectional area of the groove were made equal to the area of the set of extra cylinder ports.

In my description of the operation, I have described the operation of one end of the cyl-v inder only; but it is obvious that both ends of the cylinder being alike,.the operation of one end of the cylinder will be the same as the opposite or other end.

My invention is very simple and very efficient. The cost of its application will be very slight, and there will be no maintenance expenses, as the device becomes a permanent fixture to the engine, reducing the-counterpressure and at the same timeimproving the admission and expansion of the steam. It also possesses many valuable economic featu res, which perhaps may best be stated by referring to the subject of indicator diagrams taken from engines fitted with my improved valve.

An indicator diagram taken from an engine in practical operation fitted with myimproved valve,shows the followinginteresting and valuable features: First, the compression line, after exhaust valve closure, is considerably lowered; second, the expansion line at point of diagram or near the end of the expansion line (after exhaust valve closure on other end of cylinder or on opposite side of piston) is raised; third, the back pressure line is lowered. Each of these threefeatures result in an increase of the area of the diagram. The first feature is caused by the opening of the extra cylinder and valve ports and simply relieving the compression. The second feature is caused by the relieved compression as it passes over to the opposite side of the piston. The cause of the third feature may be stated as follows: The steam compressed is saturated steam, and when, in relieving compression, it is forced around the piston, it performs duty as ajet condenser,-

condensing the steam, thereby reducing the back pressure by lowering the exhaust line. This condensing effect does not take place until after the exhaust has reached a pressure below the compression pressure, and in a locomotive cylinder until the exhaust has served its draft purposes. This reduction of back pressure is an extremely valuable, feature. It is of course not correct to expect much of a back pressure reduction where but little back pressure exists, as in a stationary engine. Nevertheless, diagrams taken from a stationary engine, fitted with my valve, show not only a reduction of back pressure, butaslight vacuum, and these results were obtained from such astationaryengine having a free exhaust.

The amount of water contained or held in the volume of wet or supersaturated steam in a locomotive cylinder atthe time of exhaustamounted to from eleven to forty-two per centage of the whole of the steam admitted. Add to this per-centage, the per-centage of entrained Water, which according to Zeuners tests amounts to from seven and one-half to fifteen per centage,.and also the water produced by doing work, and it will be found, at least in locomotive practice, that the compression volume released (in operation) by my valve, consists of water, mostly or largely, which is at a low temperature, and this water becomes extremely effective in condensing the exhaust steam of back pressure. This operation results in an additional or fourth feature, namely: this water of low temperature being out of the way, when steam at high pressure is admitted, a better-initial pressure is insured.

By reason of the action of the extrasteam admission ports a better initial steam line may be obtained, and this fifth valuable feature is of great economic importance especially in connection with the development of power by high speed engines.

My invention possesses many minor valuable features or advantages, among which may be classed the following: Smaller clearance space can be made; higher speed can be obtained, by reasonof reducing excessive resistance in front of thepiston especially when cutting off at shortpoints of cut-off; and 'a saving of the general Wear of engine (by giving a smooth working engine) and especially in the wear of valveand seat, which has been proved in use, by reason of the valve keeping down on it's seat, and not being forced 0E its seat by excessive compression, giving good steaming qualities, as steam cannot blow under the valve to exhaust port; and an en gine will do the same work at shorter-points of cutoff.

My valve can be. applied to all engines using single slide valves of either piston or flat type.

' My invention is of special value as applied to compound engines for the reason that compression, commencing at receiver pressure in high pressure cylinder, combined with the greater area of low pressure cylinder, causes excessive compression. The clearance space can be cut down, which will give economical results.

Inthe sets of extra cylinder ports, the center port, which may be located at either side of the longitudinal center line of the valve seat, by reason of its considerable area, is the principal extra cylinder port, and the small extra cylinder ports in theside walls, if, for any reason, owing perhaps to the peculiarvconstruction of an engine cylinder, it may be considered advisable, either one or both of the small ports may be dispensed with without greatly or seriously affecting the economical operationtof .thedevice.

In applying my invention, especially to the many kinds and styles of stationary engines now in the market, it should be fully understood, -that many modifications of my invention will have to be made in order to adapt it in the best manner, to produce the results sought to be obtained, as hereinbefore set forth; but in everymoditication or adaptation, the essential feature is .the passing of the relieved compression from one end of the cylinder, around :the piston, to the other end of the cylinder.

In order to make the best adaptation of my device to a stationary engine ofa standard construction having its steam ports on the side of the cylinder and having its valve adapted to operate these ports, the weight of the valve being carriedon a horizontal plane slide, I employed the following adaptation: The extra cylinder ports, instead of starting from the valve seat, started from the slide, and the extra valve ports were so designed as to operate in connection with the extra cylinder ports, and compression release was accomplished by the relieved compression passing from one end of the cylinder through the extra valve port and then through the extra cylinder port around the piston, into the other end of the cylinder, entering the cylinder'bore at a point near thebottom ot' the cylinder. I have given this particular adaptation of my device simply to show one of the almost numberless modifications or adaptations of my invention, by means of which, compression release is accomplished, the principle of operation being substantially as herein described and claimed.

What I claim as new, and desire to secure by Letters Patent, is

1. In an engine, the cylinder provided with the

extra cylinder ports

25 and 28 their starting points at the valve seat being located ator near the longitudinal center line of and between the side walls of the valve seat, in combination with the valve provided with the

extra valve ports

39 and 40 each extra valve port being constructed, substantially as described, in order that the relieved compression may pass freely from the admission port, passing through the extra valve port in two different directions approaching a common center into and through the extra cylinder port,and then into the bore of the cylinder, for the purpose of relieving compression, substantially as set forth.

2. In an engine,the cylinder provided with the

extra cylinder ports

25 and 28, their starting points at the valve seat being located between the side walls of the valve seat, and the valve provided with the

extra valve ports

39 and 40, in combination with the extra

steam admission ports

31 and 31, substantially as described. W

3. In an engine, :thecylinder provided with the extracylinder ports 25 and 28having their starting points at the valve seat, located between the side walls of the valve seat,.and the

extra cylinder ports

24 and 26, and 27 and 29 having their starting points at the valve seat located in the side walls of the valve seat,.in combination with the valve provided with the extra valve ports 39 and etO each extra valve port being constructed substantially as described, in order that the relieved com pression may pass freely from the admission port, passin g through the extra valve port in four directions into and through the extra cylinder ports, and then into the .bore of the cylinder, :for the purpose of relieving compression, substantially as set forth.

4. In an engine, the cylinder provided with the front and backsets of extra cylinder ports and the valve provided with the

extra valve ports

39 and 40 in comhination'with the front and back sets of extra admission ports, substantially as and for the purposes set forth.

5. In an engine, the cylinder provided with the extra cylinder and the extra admission ports in combination with the valve provided with the extra valve ports, and having the sets of lugs, and exhaust cavity bridge, substantially as set forth.

6. In an engine, the cylinder provided with the extra cylinder ports and the valve provided with the extra valve ports by means of which, in relieving compression, the released compression passes from one end of the cylinder, around the piston,-to the other end of the cylinder, in combination with the extra steam admission ports, substantially as described.

7. In an engine, the cylinder provided with the extra cylinder and the extra admission ports in combination with the valve provided with the extra valve ports, and having the sets of lugs, and exhaust cavity bridge, substantially as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HENRY ROLAND FAY.

WVitnesses:

E. FRANK IVOODBURY, CHARLES L. ELLIS.

ICC