US564090A - Steam-engine - Google Patents

Description

(No Model.) I 3 sheets-411ml O. P. LITTLEJOHN.

STEAM ENGINE No. 564,090. PatentedJuly 14, 1896.

Tm: Nowms Pawns co.. mmoumo" wuumumn. a c

(No Modei.) I 3 Shets-Sheet 2.

G. F. LITTLEJOHN.

STEAM ENGINE.

No. 564,090. I Patented July 14, 1896.

(No Model.) 3 Sheets-Sheet 3.

0. F. LITTLEJOHN.

STEAM ENGINE.

No. 564,090. Patented July 14,1896.

UNITED STATES PATENT Fri CE.

CHARLES F. LITTLEJOHN, OF BRIDGEPORT, CONNECTICUT.

STEAM-ENGINE.

SPECIFICATION formingpart of Letters Patent No. 564,090, dated July 14, 1896.

Application filed January 8, 1895. Serial No. 534,272. N model.)

To all whom it may concern.-

Be it known that I, CHARLES F. LITTLE JOHN, a citizen of the United States, residing at Bridgeport, county of Fairfield, and State of Connecticut, have invented certain new and useful Improvements in Steam-Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to multiple compound engines; and it has for its object to prevent vibration, reduce the wear upon the parts, and improve the operation generally, as well as to simplify and make the construction more effective; and to this end the invention consists in the features of construction and arrangement hereinafter more particularly pointed out.

In the accompanying drawings, forming a part of this specification, and in which like letters and numerals of reference indicate corresponding parts, Figure 1 is a horizontal sectional view of the invention, taken on the line a: m ofFig. 2, the pistons and valves being removed. Fig. 2 is a front elevation of the invention, parts of the supporting-frame being in section. Figs. 3 and4 are opposite end elevations thereof. Fig. 5 is a vertical sectional view taken on the line 4 4 of Fig. 1 through one of the high-pressure cylinders and its steam-chest, parts being broken away. Fig. 6 is a detail view of the valve-operatingmechanism.

In carrying my invention into effect I employ two or more trains of compound cylinders, which together form a multiple compound engine. These cylinders are mounted upon a common frame and connected to a common crank or driving shaft, and the cylinders of one train being preferably alternated with those of the other or others. In the present instance I have shown two trains of compound cylinders, each train being a duplicate of the other, that is to say, the cylinders forming one train are of corresponding capaoity to those of the other, or, in other words, the cylinders inone train are duplicates of those in the other train or trains. The trains of cylinders are preferably arranged in vertical line with the crank-shaft, as shown, and

the crank-shaft is provided with cranks equal 4 illustrated each train of cylinders as composed of a high and a low pressure cylinder, A and B, C and D .represent the high and low pressure cylinders, respectively. The cylinders B and D are alternated with the cylinders A and C,that is to say, the high-pressure cylinders are arranged together and the low-pressure cylinders are arranged together and adjacent to the high-pressure cylinders. These cylinders are preferably arranged in vertical line with the crank-shaft, and the high-pressure cylinders are duplicates or of the same capacity, and the low-pressure cylinders are duplicates and of the same capacity,-but of different capacity from the high-pressure cylinders.

E and F, G and H are the steam-chests of the high and low pressure cylinders, respectively, and, while they may be arranged in any well-known or desirable manner, I prefer to arrange them upon opposite sides of the cylinders. As shown, the steam-chests E and F are upon opposite sides of and intermediate the cylinders A and B, and the stcam-chests G and H are upon opposite sides of the cylin ders C and D and intermediate of said cylinders.

Steam is admitted into the steam-chests E and F through a main supply-pipe 1 and branch pipes 2 3, leading from said pipe to the steam-chests E and F, respectively. Each of these branch pipes is provided with a valve 4, whereby steam may be admitted to one or the other of the steam-chests or to both simultaneously. After leaving the steamchests E and F the steam is conductedto the steam-chests G H through pipes 5 and 6, re-

spectively, and from thence through pipes 7 and 8 to a pipe 9, which may communicate with a condenser. (Not shown.)

Heretofore in the propulsion of steamships it has been common to drive each screw-shaft with two or more engines mounted upon separate frames and connected to operate the same crankshaft. This shaft is provided i11- termediate the two engines with a coupling, by means of which that section of the shaft to which one of the engines is connected may be disconnected from the main shaft and ,one engine run while the other remains idle, this being very desirable when the vessel is to be run at only normal speed. In event of an emergency, however, when increased power or speed is required the coupling between the shaft-sections is effected and the shaftis driven by both engines. A serious objection to this arrangement arises from the fact that during the action of one of the engines and while the other is out of action wear upon the crank-shaft and itsbearings. is constantly taking place, while the section of the shaft to which the inactive engine is connected remains stationary, and consequently no wear then takes place on saidshaft-section or on its bearings, and the consequence is that when the sections ofthe shaft are to be coupled they are found to be out of alinement and excessive vibration and loosening of the parts results.

It will be apparent from the description of my invention hereinbefore given that it matters not whether one of the engines or trains is operated or the other or whether both are operated simultaneously, the wear upon the crankshaft and its bearings is constantly taking place and is uniformly distributed. hen it is desired to operate only one engine, it will be understood, of course, that the other is disconnected from the crank-shaft in any suitable manner, as, for instance, by removing the connecting-rods, or, if desired, steam may be admitted only to the engine which it is desired to operate and the other may be allowed to run freely without necessitating disconnecting it from the shaft. An advantage arising from arranging the cylinders of one train or engine alternately with those of the other is that one of the cylinders of each engine is near one end of the frame and the other is near the opposite end, and consequently the strain upon the frame at one end is distributed over a greater length of the shaft and frame and upon more bearings than would be the case if the engines were arranged upon the frame side by side. In the alternate arrangement of cylinders, too, it will be noted that the high-pressure cylinders are all near one end of the frame, and consequently the pressure of the steam, which is delivered from the boilers arranged adjacent to that end of the frame upon which the high-pressure cylinders are supported, is not materially diminished, as it would be by passing the whole or substantially the whole 1 19 of devices from the connecting-rods.

sides 13 of this frame are duplicated, and

each is formed, preferably, of a single casting secured at its lower end to the main bed 1% and to the bed-plate 12 at its upper end. The four uprights 15, 16, 17, and 18 of each side of the frame are arranged in alinement with each other. The upper ends of the uprights are formed perfectly straight at 19 and aline with the pistons and connecting-rods, which are guided in their reciprocating movement by the engagement with said straight portions The lower ends of the uprights 15 and 1G, 17 and 18 diverge toward the main bed 14: and are secured thereto at points out of line with the cranks and eccentrics on the main shaft 1 to allow said parts to be easily accessible during the operation of the engines. The lower ends of the uprights 16 and 17 converge toward their lower ends and are formed integral just above thepoint \i 'heretheykare secured to the main bed 14.

The high and low pressure cylinders A, B, G, and D are provided with pistons a, b, c, and (1, respectively, having their piston-rods a, I), c, and (Z joined by connecting-rods a, b 0 and d to the cranks (1 b 0 and d on the crank-shaft I. The cranks a and b, as shown, are set at substantially one hundred and eighty degrees apart, and the cranks c and d are also set at one hundred and eighty degrees, but are at substantially ninety degrees or at right angles to the cranks a an d I)".

The steam-chests E, F, G, andII are provided with piston-valves e, f, g, and 72., the valve-stems e f 9 and h? of which are vertically guided in guides 20 of the frame L. The Valve-stems c and f are connected at their lower ends to a centrally-fulcru med horizontal lever 21 by means of links 21. One end of the lever 21 is connected by means of a short vertical lever 22 to another centrally-pivoted horizontal lever 23, which is in turn pivoted to an adjustable block 2 which slides in the slot 25 of a link 26. This link is pivoted at itsopposite ends to rods 27 and 28, which are connected to eccentrics 29 and 30 on the crank -shaft I. These eccentrics are so placed that when one is in the right position for the engines to move forward the other is in the position for moving backward, and by raising and lowering the link 26 motion will be communicated from the link 26 to the valves which it operates through the intermediate mechanism just described, and the engine will move forward or backward accordingly as. the rods 28 and 27 are in their vertical positions, respectively. It of course will be understood that the link 26 receives a reciprocating motion in its center, since when one eccentric is moving the end of the link in one direction the other is moving the other end in the other direction.

The same reference-letters have been applied to the valve-operating mechanisms of the high and low pressure steam-chests, as they are identical in construction and operation.

It is often desirable to lessen or decrease the throw of the steam-chest valves, and I have provided means for readily accomplishing this. Horizontal slots 35 are formed in the levers 23 for reception of blocks 36,which are adapted to be moved in said slots by means of screws 37 ,which have a swivel connection with said blocks. Said screws are operated by means of hand-wheels 38, secured to the ends thereof, and are provided with the usual jam nuts to prevent accidental movement. The short vertical lever 22, referred to above, which connects the ends of the horizontal levers 21 and 23, is pivoted at its lower end to the block 36, and accordingly as the block is adjusted in the slot 35 will the movement of the horizontal lever 21 and valve-stems be regulated, it being obvious that if the block 36 be adjusted to the extreme inner end of the slot 35 the length of movement of the valve-stems will be decreased,while, on the other hand, if it be adjusted to the extreme forward end of the slot the valve-stems will be caused to move a greater distance.

In the construction of my invention, as shown in the drawings, the cranks to which the high-pressure cylinders are connected are illustrated as being diametrically opposite to each other and the cranks to which the lowpressure cylinders are connected arranged diametrically opposite each other, but at right angles to the cranks of the high-pressure cylinders. It will be understood, however, that the arrangement of the cranks must necessarily be varied according to the number of trains of cylinders employed and to the number of cylinders in each train, and any ar ran gement of the cranks and cylinders whereby a constant and uniform pressure is exerted upon both sides of the crank-shaft I consider to be within the scope of my invention.

I have herein shown and described my invention as embodied in a double compound engine; but I do not wish to limit myself in this respect, as it will be evident that it may be embodied in other forms of engines, as, for instance, triple or quadruple expansion engines or in compound engines having one or more cylinders of a train superposed upon others.

The advantages of the several parts of my improvement will be appreciated by those skilled in the art to which it appertains, and within the scope of my invention, as defined in the following claims, modifications may be made in the form, construction, and arrangeshaft, said cranks radiating from points around the circumference of the crankshaft in such directions as will insure the upward and downward pressures upon the shaft being constant and at all times equalized when the whole number of trains of cylinders are in operation, substantially as described.

2. In a multiple compound engine, the combination of the trains of cylinders, the cylinders of one train being duplicates of those of the other train, pistons within the cylinders, steam-chests and their valves, a crank-shaft and connections between the pistons of duplicate cylinders and diametrically opposite cranks of the crank-shaft, said cranks radiating from points around the circumference of the crank-shaft in such directions as will insure the upward and downward pressures upon the crank-shaft being constant and at alltimes equalized, substantially as described.

3. In a multiple compound engine, the combination of two trains of compound cylinders, the cylinders of one train being duplicates of those in the other train, pistons within the cylinders, steam-chests, valves Within the steam-chests, a crank-shaft provided with an even number of cranks radiating from equidistant points around its circumference, connections between the pistons and the crankshaft, the pistons of the duplicate cylinders being connected to diametrically opposite cranks whereby the upward and downward pressures exerted upon the crank-shaft is constant and at all times equalized, and means for operating the valves of the steamchests, substantially as described.

4. In a multiple compound engine wherein the weight of the parts is equally distributed upon each side of the crank-shaft, the combination of two trains of compound cylinders the cylinders of one train being duplicates of those in the other train, pistons within said cylinders, an even number of steam-chests, one half the total number of said steamchests being arranged upon one side of the cylinders and the remaining half upon the opposite side thereof, valves within said steamchests, a crank-shaft provided with an even number of cranks radiating from equidistant points aroundits circumference, connections between the cranks and the pistons, the pistons of the duplicate cylinders being connected to diametrically opposite cranks of the crank-shaft, and means for operating the valves of the steam-chests, substantially as described.

5. I11 a multiple compound engine, the combination of two trains of compound cylinders, each train consisting of a high and a low pressure cylinder, the two high-pressure cylinders being of equal capacity and the two low-pressure cylinders being of equal capacity, pistons within said cylinders, steam-chests,.

valves within said steam-chests, a crank-shaft provided with cranks equal in number to said cylinders, said cranks radiating from equidistant points around the circumference of the crank-shaft, the cranks to which the highpressure cylinders are connected being set diametrically opposite each other, and the cranks to which the low-pressure cylinders are connected being set diametrically opposite each other but at right angles to the firstmentioned cranks whereby the upward and downward pressure exerted upon the crankshaft is at all times constant and equalized, connections between the cranks and the pistons of the cylinders, and means for operating the valves/of the steam-chests, substantially as. described.

6. In a multiple compound engine wherein the weight of parts and pressure exerted is equally distributed, the combination of two trains of compound cylinders each train con sisting of a high and a low pressure cylinder, the two high-pressure cylinders being of the same capacity and the two low-pressure cylinders being of the same capacity, pistons within the cylinders, an even number of steam-chests, one-half of which are arranged upon one side of the cylinders and the re mainder upon the opposite side thereof,valves within the steam-chests, a crank-shaft provided within an even number of cranks radiating from equidistant points around the circumference of the crank-shaft, the cranks to which the high-pressure cylinders are e011- nected being set diametrically opposite each other and the cranks to which the low-pressure cylinders are connected being set diametrically opposite each other but at right angles to the firstmentioned cranks, whereby the upward and downward pressure exerted upon the crank-shaft is at all times constant and equalized, connections between the cranks and the pistons of the cylinders, and

means for operating the valves of the steamchest, substantially as described.

7. In a multiple compound engine,wherein the weight of the parts is equally distributed upon each side of the crank-shaft, the combination of two or more trains of compound cylinders arranged in line with the crankshaft, the cylinders of one train being duplicates of those of the other train, pistons within said cylinders, an even number of steamchests adjacent to the cylinders, one half the total number of said steam-chests being arranged upon one side of the cylinders and the remaininghalf upon the opposite side thereof, each steam-chest upon one side being intermediate two cylinders and each steam-chest upon the opposite side being intermediate two cylinders and diametrically opposite a steamehest upon the other side of the cylinders, valves within said steam-chests, a crank-shaft provided with an even number of cranks radiating from equidistant points around its ci rcumference, connections between the cranks and the pistons, the pistons of the duplicate cylinders in the two trains being connected to diametrically opposite cranks, whereby the upward and downward pressure exerted upon the crank-shaft .is constant'and is at'all times equalized, and means for operating the valves of the steam-chests from the crank-sh aft, substantially as described.

8. In an engine, the combination of a pair of cylinders, pistons within said cylinders, connections between said pistons and the crank-shaft, steam-chests, valves within said steam-chests, valve-stems, a pivoted lever connected atopposite ends to the valve-stems, a second pivoted lever arranged adjacent to the first, adjustable connections between said levers, a crank-shaft, and means whereby a reciprocating motion is imparted from i the crank-shaft to the second pivoted lever, substantially as described.

9. Inan engine, the combination of a pairof cylinders arranged in line with thecrankshaft, pistons within said cylinders, connections between the pistons and the crank-shaft, steam-chests,valves within said steam-chests, valve-stems, a centrally-pivoted lever 21 con nected at opposite endsto the valve-stems, a central pivoted lever 23, connections between one end of said lever and the lever 21, a crankshaft, a pair of eccentrics on said shaft, a link, connections between said link and the eccentrics, and a sliding connection between the link and one end of the lever 23, substantially as described;

10; In. an engine, the combination of a pair of cylinders, pistons within said cylinders, connections between said pistons and the crank-shaft, steam-chests, valves within said steam-chests, valve-stems, links 21, a centrally-pivoted lever 21, a pivoted lever 23, connecting-lever 22, a crank-shaft, eccentrics 29, 3O thereon, link 26, rods 27, 2S, connecting said link and eccentrics, and connections between the link 26 and one end of the lever 23, substantially as described.

ll. In a multiple compound engine, the combination of two trains of compound cylinders, the cylinders of one train being duplicates of those of the other train, pistons within said cylinders, connections between the pistons and the crank-shaft steam-chests, valves within the steam-chests, a centrallypivoted lever connecting. the valve-stems of the steam-chests of each pair of cylinders, connections between said lever and an eccentric on the crank-shaft whereby a rocking motion is imparted to the lever to alternately raise andlower the valves of the steam-chests, nections between one end of said lever and andacrank-shaft provided with an even nuin-' the lever 21, a crank-shaft, an eccentric ber of cranks, said cranks radiating from the thereon, and connections between the eccen- 15 crank-shaft from equidistant points around tric and the lever 23 Whereby the said lever 5 its circumference, substantially as described. is operated, substantially as described.

12. In an engine, the combination of a pair In testimony whereof I have signed my of cylinders, pistons Within said cylinders, name to this specification in the presence of connections between the pistons and the two subscribing Witnesses.

crank-shaft, steam-chests, valves Within said CHARLES F. LITTLEJOI-IN. 1o steam-chests, valve-stems, a centrally-pivot- Witnesses:

ed lever 21 connected at opposite ends to the ELBERT O. HULL,

valve-stems, acentrally-pivotedlever 23,con- E. EVERETT ELLIs.

Images