US437353A

US437353A - Steam-engine

Info

Publication number: US437353A
Authority: US
Publication date: 1890-09-30
Anticipated expiration: 1907-09-30

Description

' I 3 Sheets-Sheet 2..`

C. BROWN. STEAM ENGINE.

(N0 MOdel.)

Patented Sept. 30.` 1890 me :mams Firms ce, marcruwo, wsnmerou, D. c

(No Model.)

Patented SeptQSO, 178.90.

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me mams paens coA, morn-mno., wAsmnnmN, n4 c.

f Y' UNITEDSTATES "PATENT i YOEE-VICE..v

oHAnLEs BRowrLoF NAPLES, ITALY, AssIeNoR To eUsTAv JACOB MELMs OF CHICAGO, ILLINOIS.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 437,353, cia'teseptember so, 1890.

Application nea Apiii n, 1290. i sain No. 347,434. montati.)

To all whom it may concern:

' Be it known that I, CHARLES BROWN, a resident of Naples, Italy, have invented certain new and useful Improvements in Steam-En- 5` gines; and I do hereby declare that the'following is a full, clear, and exact description thereof, reference being had to the accom'- panying drawings, and to the letters of refer-` ence marked thereon, which form a part f this specification. I

This invention relates to improvements in steam-engines, and more particularly to improvements in valves for such engines, and in features of construction in compound steamengines.

` The invention consists in the matters hereinafter described, and pointed out in' the appended claims. l

In the accompanying drawings, illustrating 2o my invention, Figure l is a central axial section through the end of the steam-cylinder of an engine, illustrating the cylinder-ports and a valve for controlling the same constructed in accordance with my invention. Fig. 2 is a sectional view of the valve shown in Fig. l, taken in a plane at right angles to the axis of the cylinder in the line 2 2 of Fig. l. Fig. 3 is a partial section, taken upon line 3 3 of Fig. l, showing the cylinder-ports in side view. Fig. 4 is a detail section, taken upon line 4 4- of Fig. l, showing one of the valvesprings in sideview. Fig. 5 is a central vertical section of a single-acting compound engine embodying my invention, the section becrank-shaft of the engine. Fig. 6 is a sectional view of the said engine on the line 6 6 of Fig. 5, a section being taken on a plane passing through the axis of the crank-shaft. Fig. 7 is a detail section of the engine-valve, taken upon line 7 7 of Fig. 5. Fig.l 8 is a section taken through the low-pressure cylinder of the engine upon line 8 8 of Fig. 6. Fig. 9 is a diagram illustrating the part of the revolution of the crank-shaft during which the valve shown in Fig. 8 is open.

A indicates an engine-cylinder, and A" one of the end walls or heads thereof, which is provided at its margin with an annular valve- 5o seat A2, in which are formed ports a et, com` ing taken on a plane at right angles to they municating with the interior of the cylinder through the head A. Y

i B is an annular valve plate or ring, which constitutes the main operative part of thel valve, and lits and turns upon the valveseat A2@ YA3 is an outer or auxiliary head, arranged external to the head A and forming with the same a live-steam space or' passage C, with which communicates a steam-supply passage, (indicated by dotted lines'at A4, Figs. l and 2.) In the particular construction shown in the drawings'the head A3 is cast integral with the cylinder-head land connected therewith by Webs t3 a3. i

YD is a steam-exhaustlpassage, of annular form, surrounding the valve-ring B, said passagebeing formed by an external Wall A5, herein shown'ascast integral with the head A. f

`An annularslot or opening between the margins of the external head As and the external Wall A5 of the exhaust-passage m is closed by an annular plate or coverE, located opposite the valve-ring B.' Said slot or'opening is made of proper size to admit the said valve-ring, and the latter may be taken outl through the said slot by theremoval of said cover E. The steam-inlet passage A4 is herein shown as extending through the exhaust-passage D and ybetween Ythe valve-seat and the head A in one of the spaces 'between twov cf l the ports a ot, Fig. 2.

The valve-ring B is provided with a series of recesses or notches ZJ b, opening both at the inner edge and inner flat face of the valve and arranged to correspond in number and angular positions withl the ports ct ct of the valve-seat A2. The said recesses bb communicate at the inner edge of the ring with the steam-space C, and serve to admit steam to the said ports when oppositelthe same. In

the instance illustrated the valve-ring is pro` vided with eight of such notches b b. At points intermediate to the notches b b the valve-ring is provided with a second series of notches o b', which open` at the outer edge' and inner flat face of the ring and serve to bring the ports a a, into communication with the exhaust-passage D.

IOO

F is a packing-ring, which is inserted between the valve-ring B and cover E for making a steam-tight joint between the live-steamv and exhaust passages or chambers. Said ring F revolves wit-h the valve-ring and fits steamtight against the main surface of the said cover. A steam-,tight joint is formed between the valve-ring and packing-ring by-means of an annular packing-strip e', which bears against the inner cylindric faces of the valvering and an inwardly-extending flange e of the packing-ring, which flange iits within an annular recess or rabbet b2 in the inner face of the valve-ring. The outer cylindric face of said packing-ring andthe iiange'thereon is in contact with the cyliudric surface of the rabbet b2, but the edge of said flange stands normally free from the opposing surface of the -valVe-ring when the valve-ring rests on its seat and the packing-ring is in contact withth'e cover E, said ring being held or supported in contact with the cover by means of a plurality. of springs f f, which are interposed between the packing-ring and valvering, and act expansively to throw said rings apart. The springs ff are herein shown as `made of metal strips bent to engage at their middle parts and ends with the parts between which they are placed, as shown in Fig. 4. By the-construction,described not only are the valve-ring and packing-ring held at all times in contact with their seats, notwithstanding wear in the parts, which is taken upby thesprings ff, but the valve-ring, being movable outwardly by reason of its sliding connection with the packing-ring, is free to rise from its seat when water is present within the cylinder, to permit the escape of the same without danger of breaking the cylinder-head. The packing-ring F bears against the cover E at the inner portion only of its outer'surface, and it follows fromthis construction and the shape of said ring, as above described, that the steam-pressure on said ringis-balanced, except in the small area in-I cluded between the two circles of which the diameters are indicated bythe lines 1 and 2 in the drawings. 'The valve-ring B is made of suchcross-sectional shape and the packing-ring is so located with reference thereto that said valve-ring is partially relieved from steam-pressure on its rear or outer surface, inasmuch as the steam-pressure acts only on that area included between the two circles of which the lines l and 3, Fig. l, represent the diameters, and the unbalanced pressure is still vfurther reduced, because it is only active to its full extent on those parts of the eight cylinder-ports a a and the corresponding exhaust-notches b b which arelocated immediately under the pressure-zone included between the circles of which the lines l and 3 are the diameters.

The valve-ring B receives motion from the crank-shaft or other moving part of the engine'through the medium of a pinionG, which is mounted upon a shaft G and intermeshes with a circular rack B', formed on the circumference of the valve ring. The said pinion G is located within the exhaust passage or chamber D in the manner shown in Figs. l and 2, the shaft G passing through a stufIing-box g, where 'it makes its exit from the chamber, so as to prevent the escape of steam at this point. Y As shown in the drawings, the wall A5 of the exhaust passage or chamber is divided on a line passing through the bearings of the shaft G', Fig. 2, to form a separate cap or cover A6, which may be removed to obtain access to the pinion G. rlhe shaft G in case the same is driven by thecrank-shaft of the engine, may be connected therewith by any suitable gearing, such, for instance, as that shown in Fig. 6 and hereinafter described. Said shaft will be so actuated that at each revolution of the crankshaft the valve-ring B will be turned an angular distance equal to the angular distance apart of the steam-ports inthe cylinder--that is to say, in a valve having eight steam-ports, as herein shown, the valve-ring B will make one revolution to -eight turns of the crankshaft. v

To now refer to the operation of the valve, Fig. 2 shows the valve-ring in its proper position at the commencement of the stroke, the ports being already partially uncovered for the admission of steam a distance technically known as the leadthat is to say, the distance by which the advance edge b3 of the inlet-notch b is separated from the edge a of the steam-ports. As the piston moves, the valve will continue to revolve until the edges b4 of the several notches b coincide with the edges a2 of the cylinder-ports, when the admission of steam ceases. The notches b b control the periods of exhaust and compression in a similar manner, opening communication of the cylinder with the exhaust by their edges b5 b5 passing the edges a a. of the cylinder-ports and closing the exhaust by their edges b bpassing the edges a2 a2 of the cylinder-ports. The spacing of the notches b b and h b and that of the ports a a is so Vadjusted as to control the periods of admission and exhaust according to the requirements of theory and practice.

In Figs. 5, 6, 7, and 8 is shown asingle-acting compound engine, to the high and low pressure cylinders of which are applied valves of the type v above described. As illustrated in said iigures, H is the small or high-pressure cylinder, and I the large or low-pressure cylinder, of the engine, said cylinders being arranged end to end and having interposedv between them a casting J, which forms the upper head of the cylinder I. Within the cylinder I is a piston t', having a tubular piston-rodi', and the cylinder H contains apiston h', having a piston-rod h2, which passes through a central hub J2 of the castingJ and through the piston t' and its tubular pistonrod. Both of said piston-rods are connected with a singlel crank-shaft Q, as hereinafter IOO IIO

more fully set forth. In the upper surface of said casting J is formed an annular valveseat J', and within said casting, outside of said valve-seat, is formed an annular exhaust passage or chamber J 2. jjj are steam-ports leading from the valve-seat J into the lowpressure cylinder I. The high-pressure cylinder H is provided at its end adjacent to the cylinder Iwith an integral head H', upon the outer surface ot' which is formed an annular valve-seat H2,within which is formed a series of ports h h h,leading to the said cylinder.

K is a valve-ring, fitting upon the valve-seat J and provided with steam inlet and exhaust notches or recesses 7c lo k' k', constructed and operating in all respects like the valve-ring shown in Figs. l, 2, and 3. A packing-ring L like that shown in Figs. l, 2, and 3 is also employed, together with a packing-strip Z, to make a steam-tight joint between the valvering and the packing-ring. The valve-ring K controls the admission of steam to and its exit from the low-pressure cylinder. In this instance, the cylinder H is provided with an outwardly-exten'din g annular flange H2, which is secured at its outer margins to the casting J above the exhaust-chamber J sand the valvering K and forms a cover for said parts, said flange being provided with an annular rib h4, forming a bearing-surface for the packingring L.

M is asecond valve-ring, similar to the valverink K, but located within the latter and resting in contact with the annular valve-seat H2 of the high-pressure cylinder. Said valvering controls the admission of steam to the high-pressurelcylinder. N is a packing-ring, located between the said valve-ring M and an annular seat or bearing-surface J 4, formed upon the casting J, inside of the valve-seat J A packing-strip fn serves to make a steamtight joint between the valve-ring M and the packing-ring N.

O is a live-steam chamber, formed in the casting J between the valve-ring N and the `head 0f the low-pressure cylinder, said chamber being of annular form and occupying the space between the cylinder-portsjj and the central hub J2 of the casting J. Steam is admitted to said chamber O through a radial steam-inlet passage O'. (Shown in Fig. 6.)

The valve-ring M is supplied on its inner or live-steam circumference with an automatic cut-0E valve for controlling the admission period, said Valve having the form of a cylinder P, provided with ports p, which operate in connection with the admission openings or notches m of the valve-ring M. Said cylinder P extends from the valve-ring M to the bottom of the steam-chamber O, having bearing againstthe inner surface of saidvalve-ring M and against the exterior of the central hub J2 of the casting J. An annular space is formed between the exterior of the cylinder P and the bearing-surface J1 and packing-ring N, to allow the passage of live steam from the chamber Q to the space between the packing-ring N and the cylinder P, and said cylinder is provided with a series of apertures 10', allowing the passage of steam through the cylinder to an annular space or chamber P', formed between the upper part of the said cylinder and the hub J2. The steam passes from said space P through the ports p of the cylinder P into the passage m of the valve-ring M. The cylinder P, constituting the cut-off valve, is held in any angular' position desired, so as to cut off the steam at any desired point in the stroke of the piston. Any desired or suitable means may be employed 'to give motion to the cylinder P from the exterior of the casting J--as, for instance, the said cylinder may be provided with external gear-teeth P2, engaged with a rack-barv P2, to which is attached a rod P4, extending outwardly through the steam-inlet passage O', or a similar passage provided for the purpose. The rod P4 will usually pass through a suitable stufing-box, and may be connected with any suitable regulating device or governor.

The valve-ring M operates in the same manner as thevalve-rin gB, hereinbefore described, to bring the ports p of the cut-off valve and the exhaust-space alternately into communication with the high-pressure cylinder. Such exhaust-space is included between the valverings K and M, and the valve-ring K operates to bring said exhaust-space and theexhaust-passage J 2 alternately into communication with t-he low-pressure cylinder I. The valve-ring K is connected with the valve-ring M by means of interitting projections m2 m2 m2, Fig. 7, on said parts, so that the said valvering M is moved by and with the said valvering K, the latter being actuated by means of a pinion Gupon a shaft G engaging gearteeth K' on the valve-ring, in the same manner as hereinbefore described. Motion is given to the said shaft Gr' from the engine crank-shaft Q in the construction shown by means of a pinion R upon the shaft engaginga spur-wheel It on the shaft fr, on which is mounted a gear-pinion R2, intermeshing with the gear-pinion G2 on the shaft Gr'.

,S is a supplemental valve for controlling the exit of steam from the exhaust-chamber J3 of the low-pressure cylinder. Said valve- S has the form of a hollow cylinder secured to and revolving with the shaft, said cylinder being open at its ends and in communication with said exhaust-passage J2. Said valve rotates within a cylindric seat S', located at the side of the cylinder I and in communication at one end with the said chamber J 2, said seat having opposite ports S2, communicating with the exit steam-passage S2, leading to the open air or to a condenser. Said valve S is provided with ports s s, corresponding in size and l0- cation with the ports S2 S2 of the valve-seat. The purpose of the valve S is to open communication between the low-pressure cylinder and the condenser or exhaust during such portion of the revolution of the engine as may IOO IIO

same. In the diagram Fig. 9 the shaded part of the circle indicates the part of the revolution during which the valve may remain open with good results, the same being about onethird of a complete revolution of the crankshaft. By making the period during which the low-pressure cylinder is in communication with the exhaust or condenser` about onet-hird of a revolution of the shaft the period during which the cooling and re-evaporating process takes place (which is one cause of the useless expenditure of heat in a steamengine) is reduced to a minimum.

The engine illustrated embodies as a separate and further improvement means for affording a rapid escape of exhaust-steam from the cylinders, consisting of an annular. eX- haust-port in each cylinder, which exhaust'- port is uncovered by the piston when the latter is atv the extreme end of its stroke. In the construction illustrated the high-pressure cylinder H is provided with an annular exhaust-port H4, opening into a passage H5 in or surrounding the walls of the cylinder,

which passage communicates with the spacebetween the valve-rings K and M. The lowpressure cylinderI is provided with a similar annular port I', communicating by means of passages I2 I2, cast on the wall of the cylinder, with the exhaust-chamber J 3. At the side of the cylinder I,.adjacent to the valve S, the port I is desirably arranged tocommunicate directly with the valve-casing S', as clearly shown in the drawings, Fig. 6. v

The supplementary exhaust-ports I-I4 and I afford a large exhaust-opening as soon as the annular ports with which they are connected are uncovered by the pistons, thereby insuring the rapid and complete discharge of steam and moisture from the cylinders. The passages H5 and I2 prevent unduel compression at the end of the working-stroke of each piston, inasmuch asthey form a means of communication between the opposite sides of the piston during the period that the exhaust-ports ofthe valves. Kand M are open, thus allowing thesteam to circulate freely between the spaces-at opposite sides vof thepistons at such times.

,The valve S constitutes an important improvement in steam-engines, and especially in compound high-speed engines, whereby the latter are better adapted to work either as condensing or, non-condensing engines. When the engine is. working with condensation, during the upstrokeof the piston in the highpressure cylinder the connection with the condenser and the low-pressure cylinder is cut off. It follows that the pressure of steam on opposite sides of the said piston during such upstroke of the piston is the same as at the completion of the stroke, steam circulating freely both above and below the piston, so that when thevalve-ring K cuts off the exhaust a sufficient quantity of steam is confined to produce by compression sufficient end pressure to'absorb the momentum of the piston z' of the low-pressure cylinder and parts moving in one direction, and inasmuch as no reversal.

in the direction of the pressure in said parts takes pla-ce a silent motion is secured and pounding is avoided. v

4 As a further and separate improvement, I have provided a novel construction in the pis- `ton and connecting rods of a steam engine, as follows: Each of the two separate piston-rods h2 i above described gives an impulse tothe crank-shaft during one-half of the revolution ofthe crank, the impulse of one piston-rod being in an opposite direction to that-of the other piston-rod. Any lost motion in the `crank or cross-head bearings in a construction of this kind will produce pounding, an-d to lessen` liability thereof I provide the follow- The cross-head and crank-pin.

ing construction, as more clearly shown inV Figs. 5 and 6. with the piston t' of thelow-pressure cylinder, which is hollow or tubular for the passage of the piston-rod h2, as hereinbefore described, is connected with one half U of a: two-part cross-head, which is indicated as awhole by U. Said piston-rod'h2 of the highpressure cylinder is connected with the other part U2 of the said cross-head, said parts of 4,the cross-head being movable relatively to each other, while at the same time engaging the cross-head guides T T, so as to properly guide the piston-rods. In the particular construction shown, the part U of the cross-head is provided at its ends with integral guideplates u u, which immediately engage the cross-head guides, while the part U2 is provided with short bearing-surfaces u u on its ends, which rest and slide in contact with the said plates u u. v

V V are springs applied to draw the parts of the vcross-head toward each other, said springs, as herein shown, being of spiral form and placed between the part U oftthe crosshead and nuts or heads o fu upon bolts ov fU, which bolts pass through the part U of the cross-head and are secured to the part U2 thereof.

The crank-pin bearing is made in two parts or sections W W, the section W coveringy the part of the bearing nearest the cross-head, while the section W covers the part of the crank-pin remote therefrom. Said part W of the bearing nearest the cross-head is connected with the latter by means of two connecting rods or bars W2 W2, which are rigidly secured to said part W of the bearing and engage bearing-pins u2 u2 on the part U ofthe divided cross-head. Thelower section W of th'e divided bearing is connected with the part U2 of the divided cross-head by means of a connecting-rod W3, which is forked at its upper end and provided with a wrist-pin w,

passing through the said part U2 of the crossh head. The pressure downward ofthe pistonrod t" keeps the part U of the cross-head and the connecting-bars W2 W2 always in comv The piston-rod vl', connected IOO IIL

pression, there being no reversal in the direction of the force exerted upon the crankshaft by or through these parts. The piston t' of the low-pressure cylinder, therefore, operates under the same conditions as any singleacting engine and can be run without the other half of the crank-pin bearing. The piston-rod h2, which passes freely through the hollow rod i', acts upon the crank-pin through the medium of the lower part U2 of the crosshead and the connecting-rods W3 W3, and inasm uch as said piston always receives pressure of the steam on its under side the transmitting parts are always in tension and there is no reversal in the direction of force, so that these parts can also work independently of the parts operating on the other half of the crank-pin. It follows that any lost motion in the bearings will not produce pounding, because the steam acts from below in the highpressure cylinder andfrom above in the lowpressure cylinder on the pistons and keeps the halves of the crank-shaft bearingV constantly in contact with the same. In stopping or start-ing the engine, the steam-pressure upon the pistons at such time being absent, there would be nothing to prevent pounding in the absence of said spring, and the latter are therefore employed to hold the parts of the crank-pin bearings always in contact with said crank-pin.

The features 0f construction above described are especially valuable and useful for highspeed engines.

One advantage arising from the construction herein described is that the cylinder-ports are very short and afford direct communication between the steam-chamber of the valve and the cylinder.

The novel construction in the valve herein described is especially valuable in a compound engine, because the construction in the steam-distributing devices permits the whole of such devices to be included in a space between the covers of the high and low pressure cylinders, thereby affording short and direct passages for the steam in passing from one of said cylinders to the other and involving little diminution of pressure and little or no loss of heat from radiation. Furthermore, this construction and location of the distributing devices aford a jacket for the cylinder ends, preventing the loss of heat from the same. The intercepting valve S operates to reduce to a minimum the period during which the walls of the low-pressure cylinder are exposed to the cooling eect of the condenser or exhaust. A single-acting compound engine having the divided crank-shaft bearing and independent devices for transmitting power from the two pistons 'to the crank-shaft has the advantage of the single-acting type of box engine-to wit, compactness, smooth` ness of working, self-lubrication, and of requiring little attention. A The engine herein described, however, having no open-ended cylinder in direct communication with the box-room, the lubricant is not spoiled by the water of condensation, which always finds its way past the packings of the pistons in this'class of engines as usually constructed.

I claim as my inventionl. The combination, with an engine-cylinder having live-steam and exhaust chambers and provided with an annular valve-seat having a plurality of ports therein and an annular bearing-surfaceY opposed to said valveseat, of a movable valve-ring bearing at its opposite faces against said valve-seat and bearing-surface and separating the said livesteam and exhaust chambers, said valve-ring being provided with two sets of recesses or notches opening, respectively, at the inner and outer cylindrical surfaces of said valve-ring and both communicating with its bearing-surface, which is in contact with said valve-seat, substantially as described. v

2. The combination, with an engine-cylinder having live-steam and exhaust chambers and provided with an annular valve-seat having a plurality of ports therein and an annular bearing-surface opposed to said valveseat, of a movable valve-ring bearing at its opposite faces against said valve-seat and bearing-surface and separating the said livesteam and exhaust chambers, said valve-ring being provided with two sets of recesses or notches, opening, respectively, at the inner and outer cylindrical surfaces of said valvering and both communicating with its bearing-surface, which is in contact with said valve-seat, said valve-ring embracing a packing-'ring bearing against said annular bearing-surface and having sliding engagement with the valve-ring, substantially as described.

3. The combination, with an engine-cylinder having live-steam and exhaust chambers and provided with an annular valve-seat having a plurality of ports therein and an annular bearing-surface opposed to said valve-seat, of a movable valve-ring bearing at its opposite faces against said valve-seat and bearingsurface and separating the said live-steam and exhaust chambers, said valve-ring being provided with two sets of recesses or notches opening, respectively, at the inner and outer cylindrical surfaces of said valve-ring and both communicating with its bearing-surface, which is in contact with said valve-seat, said valve-ring embracing a packing-ring bearing IOC ITS

against said annular bearing-surface and havpressure cylinders of a compound engine arranged end'to end and having on their adjacent ends annular valve-seats having a plurality of ports, of exhaust and live steam chambers and valve-rings upon said seats separating said chambers and provided with two sets of notches opening at opposite sides of the rings, substantially as described.

6. The combination, with the high and low pressure cylinders of a compound engine arranged end to end and having on their adjacent ends annular valve-seats having a plurality of ports, of exhaust and live steam chambers, valve-rings upon said seats, provided with two sets of notches opening at opposite sides of the rings, and a cut-off valve consisting of an apertured movable cylinder located between the valve-ring which controls the high-pressure cylinder and the livesteam chamber, substantially as described.

7. An engine-cylinder provided at one end with. steam-inlet ports and exit-ports and a valve controlling the same, and with an annular v exhaust-port at the opposite end of the cylinder, combined'with a piston in said cylinder, said annular exhaust-port being located in position to be uncovered by the piston at they end of the stroke of the latter, substantially as described.

8. The combination, with the high and low pressure cylinders of a compound engine arranged end to endl and having at their adjacent ends annular valve-seats having a plurality of ports, of exhaustand live steam chambers or passages, valve-rings upon said seats, each provided with two sets of notches opening at opposite sides of the rings, the

high-pressure cylinder being provided at its opposite or outer fend with an annular exhaust-port communicating with the steamspace between said valve-rings, and said lowpressure cylinder being provided with a similar annular port communicating with the eX- haust chamber or passage, substantially as described.

9. The combination, with two single-acting cylinders arranged end to end, of pistons in said cylinders and piston-rods, one of which is tubular for the passage of the other, a crankshaft, a divided crank-pin bearing, the parts of which are separately connected with said pistons, and a spring or springs applied to hold the parts of the bearings in Contact with the crank-pin, substantially as described.

10. The combination, with two single-acting cylinders arranged end to end, of pistons in said cylinders, piston-rods, one of which is tubular for the passage of the other, a twopart cross-head, the parts of f which are separately attached to the piston-rods, a crank shaft, a divided crank-pin bearing, the parts of which are separately connected withthe of two vwitn esses.

CHARLES BROWN.

Witnesses:

EDWARD OAMPHAUSEN, v NEsToN CALvANo.