US410190A

US410190A - Steam-engine

Info

Publication number: US410190A
Authority: US
Publication date: 1889-09-03
Anticipated expiration: 1906-09-03

Description

(No Model) W. A. PITT.

STEAM ENGINE.

No. 410,190. Patentd Sept. 3. 1339.

N FEI'ERS, WWI-barium Wnhingtm D. Q

- UNITE STATES PATENT OF ICE.

WILLIAMA. PITT, on eL'ENBRooK, CONNECTICUT.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 410,190, dated September 3, 1889.

Application filed October 21, 1887. Serial No. 252,958. (No model.)

To all whom it may concern.-

Be it known that I, VVILLIAM A. PITT, a citizen of the United States, residing at Glenbrook, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Steam-Engines, of which the following is a full, clear, and exact specification, reference being had to the drawings accompanying and forming a part of the same.

My invention relates to improvements in steam-engines; and the object of my improvements is to obtain the fullest theoretical duty of the steam and other elastic forces in engines; and this I attain by cutting off the steam, &c., at initial pressure ata given point in the cylinder, and making up for all loss due to the expansion of the same by means of constantly-increasing leverage from the start to the finish of a given stroke of the piston, using two cylinders and two sets of cranks, and intermediate cranks having alternate movements, one from the minimum to the maximum and the other from the maximum to the minimum, wherebya mean power is eifected throughout the entire stroke of the engine. This object I attain by the mechanism illustrated in.,the accompanying drawings, in which.

Figure 1 is a side elevation of the engine; and Fig. 2 is a top plan view of the same, the two views showing clearly the nature of my improvements.

Let a 0, represent two stean1-cylinders of equal dimensions arranged side by side.

19 b are the pistons, and e e the respective piston-rods of the same.

61 d are two horizontal shafts suitably mounted in the bed or frame of the engine, (the latter not being shown in the drawings;) and p12 are cranks set on the shafts d and d, which are connected by the pitmen g g with the respective piston-rods e and e.

By reference to Fig. 1 it will be observed that the cranks p and 10 are set on their shafts d and d so as to stand at right angles to each other. The shafts d and d are arranged in the same vertical line and at a distance from each other in such vertical line equal to the length of the stroke of the pis tons in the steam-cylinders a and a.

On the lower shaft dare mounted the cranks at right angles to the intermediate crank,

which is connected with the steam piston-rod. The cranks c c and c c are connected,.by means of the rods ffand ff with two other sets of cranks 71; h and h h on the workingshaft is, which are set opposite to each other and on the same horizontal plane, as is clearly shown in Fig. 1. The working-shaft k is placed at a distance desirably remote from the two steam-cylinders and on a plane about midway between the shafts d and d.

In operation, the steam being admitted into the steam-cylinders, the pistons of the same will be made to travel in opposite directions, and all the cranks will be caused to take an alternate corresponding action, each moving in the direction shown by their respectivearrows in Fig. 1. By reason of the pistons Z) I)? in the cylinders a a being connected with the cranks 19 p in a line a little off of the deadcenter, and the cranks h h being connected to the cranks c and c, the most remote point from the same dead-center, shows that the pistons are operating to the greatest disadvantage at the beginning of the stroke, where a greater travel in a horizontal plane takes place by the cranks o c and c c in overcoming the resistance at the work-shaft with a much less travelin the same distance of the said steampistons, but with a continual increasing power toward the end of the stroke, at which point the operation is j ust reversed and a much less travel through a horizontal distance by the cranks c c c c is occasioned by a much greater travel left to be performed by the steam-pistons, both cranks p 0' being moved only one fourth of a complete revolution to the'right.

The cranks c and o beiiig twice the length of the cranks h and 72/ causes the latter, by means of their pitmen, to be moved the same distance in the same direction as themselves in making a one-fourth of a revolution; but the cranks h and It will make a one-half revolution in the same time, and thus equal one stroke of the pistons b b in the steam-cylinders. The double cranks c c and c c operate the cranks h 71. and h 77.,which are of halflength, and the movement of all these cranks is such that when the steam is pushing and pulling them they will always at some point afiord an increasing length of leverage to v a decreasing steam-power, and are always made to maintain a reciprocal position to each other. At the end of the first stroke it will be seen that the preponderance of leverage is all in favor of the steam and against the resistance to be overcome in the cylinder a, and, vice versa, in the cylinder a. The two cylinderpistons operating their cranks upon their individual and intermediate shafts (Z and (1' alternately causes a minimum of power in the one and a maximum of power inthe other to always take place at the same time and at the extreme end of their strokes, thereby effecting a constant force equal to boiler-pressure or mean power throughout the entire operation of the engine on each and every stroke of the piston. Thus in an engine operating with sixty pounds of steam it is possible to out it off at one-eighth of the stroke, or a little further on in the steam-cylinder, being with my improvement an equivalent to cutting off the steam at a one-quarter of the stroke of the piston in a single-acting high-pressure cylinder, and allowing it to expand in the same cylinder with a result better than that obtained in compound engines with an expenditure of only about one-fourth of the fuel.

My improvements are equally applicable to all classes of engines as well as air-compressors and vacuum-pumps and other styles of pumps, no material change being necessary to adapt them to all these purposes.

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

1. In combination, two cylinders with theirpistons and piston-rods, two sets of cranks mounted on independent shafts set in the same vertical plane, each set being placed at right angles to the other, two sets of cranks set on the same plane on the work-shaft and connected therewith, and two intermediate cranks set on the said independent shafts at right angles to each other and to the other cranks and connected with the pistons in the respective cylinders, all arranged in the manner and for the purpose set forth.

2. In an engine, the combination, with two cylinders, their pistons, and piston-rods, of two shafts set in the same vertical plane, two sets of cranks placed at right angles to each other on said shafts and connected with two cranks mounted on a common shaft set on a plane intermediate between the said inde pendent shafts, and two cranks set on the independent shafts and connected with the piston-rods, as set forth.

3. In combination, the cylinders a a, with pistons and piston-rods b b and e e, shafts d d, placed in the same vertical plane, cranks p p, connecting-rods g g, double cranks c c, and double cranks h h, with connectingrods ffff, as set forth.

4. The combinatiomwith two cylinders and their pistons and piston-rods and workingshafts, of two shafts placed one above the other and equidistant from the direct line of motion of the engine, two pairs of cranks set at right angles to each other on said shafts, and intermediate cranks set on the same shafts at right angles to each other and to the aforesaid cranks, and rods connecting the said cranks with the piston-rods and workingshaft, as set forth.

5. In an engine, a leverage consisting of double cranks placed on independent shafts between the piston cross-heads and crankshaft and connected with double cranks of half-length on the crank-shaft, and cranks interposed between the double cranks and connected with the steam piston-rods, substantially as set forth.

WILLIAM A. PITT.

lN'tnesses:

HERMAN G. Lonw, K. NEWELL.