US255854A - Engine - Google Patents

Description

(No Model.) '3 Sheets-Sheet 1.

M. W. HALL.

STEAM ENGINE. No. 255,854. Patented App l, 188.2.

INVENTORZ ATTEsT:

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M. W. HALL.

(No Model.)

3 Sheets-Sheet 2r STEAM ENGINE.

Patented Apr. 4.18 82.

INVENTCIRZ A' TESTZ m UNITED STATES PATENT O FICE.

MILAN W. HALL, OF PLAINFIELD, NEW JERSEY, ASSIGNOR OF ONE-HALF TO ALBERT E. HALL, OF SAME PLACE. I

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 255,854, dated April 4, 1882.

Application filed February 5, 1881.

To all whom it may concern Be it known that I, MILAN W. HALL, a citizen of the United States, residing in Plainfield,Union county, New Jersey, have invented certain Improvements in Steam-Engines, of which the following is a specification.

This invention relates to thatclassof engines which employ twooylinders, the piston in one cylinder operating the valve which controls the admission of steam to the other cylinder.

The-novel features consist partly in the construction and arrangement of the valves, ports, &c., and partly in the construction and arrangement of the reversing mechanism.

In the drawings, which serve to illustrate my invention, Figure l is a sectional plan, the cylinders, valve-chest, &c., being in horizontal section in the plane of the line a; a: in Fig. 3. Fig. 2 is a front elevation of the engine from in front of the cross-heads. Fig. 3 is a crosssection of the engine, taken in the plane'of the line 3 y in Figs]. Fig. 4 is a plan of the valve detached. Fig. 5is a detached sectional view on line a 2, Fig. 3, arranged to illustrate the reversing mechanism. Fig. 6 is a sectional plan arranged to illustrate my improved engine without the reversing mechanism, as applied direct.

Beferring to the first five figures of thedrawings, A A are twin cylinders, provided with the usual pistons, B B, piston-rodsO O,orossheads D D, cross-head guides E E,suitable connecting-rods, and. cranks F F, fixed at right angles to each other on shaft Gr.

His asteam-chest, arranged to receive steam in the usual manner through a pipe, I. This steam-chest is arranged for convenience between the cylinders, and is employed in common for the valves in both engines. It might, however, be divided by a partition into two chests, and each be arranged to receive steam independently of the other.

J J are the valves, which operate generally as ordinary slide-valves, but have some peculiarities of construction and arrangement. These valves are connected by means of rods a a. with arms K K, which project inwardly from the cross-heads D D. It will be seen that the arrangement is such that the valve which controls the ports of one engine is (No model.)

moved or shifted by the movement of the piston in the other, and that the valve-stroke equals the piston-stroke, the two being cou pled indirectly together. The valve is long and narrow, and the ports b I) b in the cylinders are also long and narrow to correspond, their form and arrangement in this particular being precisely the reverse of that in other engines as ordinarily constructed.

L L are what I denominate port-plates, whichare interposed between the valves and the ports. These are supplied with ports or apertures c c and passages which form a means ot'communication between the ports in the cylinder, and the valveand steam-chest. The portplates are arranged to form seats for the valves, and play vertically whenthe engines are to be reversed, as will be described.

In Fig 1, I have shown the steamports I) 1) arranged to open directly into the cylinders in both engines; but it is necessary in my arrangementthat these ports should be crossed in one engine-that is,that the portuncovered at the out end of the cylinder shall admit steam to the in end, and vice versa. This will be obvious without further explanation. To accomplish this result, however, I cross the ports or port-passages in the port-plate instead, as the preferable construction, as indicated by the dotted lines in Fig. 5.

I have shown the piston B at half-stroke and moving in the direction of the arrow, and the piston B at the end of its out-stroke and ready to return. The first movement of the piston B beyond the halfstroke will carry forward the valve J of cylinder A and uncover an inlet-port, c, in the port-plate, which admits steam (through a port, 0, in the cylinder) in front of the piston B and starts it back on 1 its return-stroke. In moving back it carries back the valve J of the other cylinder, and

when the piston B reaches the end of its outstroke, the piston B will have reached the middle of its stroke, and carried the valve J far enough to uncover the port and admit steam in front of piston B. Thus each piston in its travel alternately opens and closes the ports of the cylinder adjacent, and the valves travel the same distance as the pistons, and are coupled rigidly but indirectly to them.

Referring to Figs. 3 and 5, I will now describe the mechanism for reversing the engines.

The port-plates L L are arranged to slide up and down in the slide-chests M M, connected with the steam-chest. Only one of these port-plates, L, is shown in Fig. 5 but it will be understood by reference to Figs. 1 and 3 that the crossed ports a c in the 'plate L are arranged above the plain ports c; or it may be assumed that the plate L is precisely like the plate L, but inverted in position, so that when both plates are down, as in Fig. 3, the plain ports in L will coincide with the cylinder-ports, while in L the cross-ports will so coincide.

To the port-plates are aflixed stems N N, by which they can be moved up and down, and these stemsmay be yoked together, as in Fig. 3, so that they can be operated simultaneously by one stem or rod 0. I have not shown any mechanism for operating the port-plates, and any means may be employed. WVhen the engines are to be reversed the port-plates are simultaneously lifted until the lower ports in each plate are brought to coincide with the cylinder-ports, and as this shifts the crossed ports from one engine to the other, as will be readily understood, the conditions otadmission of steam will be reversed and the shaft G will be rotated in the opposite direction.

In lieu of shifting the port-plates vertically, I may arrange them to be moved horizontally; or they might be madein theform of segments or quadrants and arranged to turn on an axis. The main point is to shift the crossed ports from one side to the other.

Instead of arranging the valves in the same horizontal plane and causing the arms K K to lap past each other and arch over the valvestems, I may set the valves in the same vertical plane, one above the other, and arrange the ports and passages to suit; orI may even arrange the valves in different horizontal planes, but not in the same vertical plane.

The cylinders may be set in a vertical, horizontal, or inclined position.

In Fig. 6 I have shown my improved engine applied directly to a pump without the intervention of a rotative mechanism In this construetion the piston-rods are not connected in any way, and the reversing mechanism is omitted. Otherwise the construction is the same as that shown in Fig. 1, except that the ports or port-passages in the cylinder A are crossed, for obvious reasons.

As my valve is narrow, it will be found that notwithstanding its unusual length it has little more area for the steam to press on than the ordinary slide-valve; and to lessen the area of pressure still more I raise the seat of the valve slightly, so that when the valve passes its central position over the ports the laps at its ends pass out beyond the seat, so that the steam may get beneath them, and thus relieve the pressure.

. I am aware that it is not new to operate the valve controlling the admission of steam to one cylinder by the piston which plays in the adjacent cylinder, and'that sliding port-plates for reversing are not, broadly considered, new; but I am not aware that my herein-described construction and arrangement of these parts has ever before been known or used.

Having thus described my invention, I claim--- 1. Asteam or other engine employing a slidevalve and the usual inlet and exhaust ports, in which the valve has a strokeequal in length to the piston,and the longest axis of the portopening under the valve is in the plane of travel of thevalve, substantially as set forth.

2. The combination, with the two cylinders and their pistons, rods, cranks, common shaft, and valves, actuated as shown, of the two portplates L L, yoked together and arranged to be shifted simultaneously, said port-plates being provided with one set of plain and one set of crossed ports, arranged inversely in the two plates, whereby, when the plates are shifted, the crossed ports of one plate will be brought into play and those of the other plate thrown out, substantially as and for the purposes set forth. I

3. In a duplex engine, the combination of two steamcylinders, one provided with direct steam-ports, and the other with crossed steamports, two slide-valves controlling said ports, two piston-rods, and-mechanism connecting the piston-rod of each engine with the valve of the opposite engine, for moving said valves in the same direction as said piston-rods, substantially as specified.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

MILAN W. HALL. Witnesses:

HENRY CONNETT, GEO. BAINTON.

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