US8039A - Steam-engine - Google Patents

Description

y UNIrEDsTATEs PATENT' onirica.

RICHD. F. Lorna AND JOHN w. NYsTRoM, or PHILADELPHIA, PENNsrLvANIA.

Speccationof Letters Patent No. 8,039, dated April` 135,` 1851.

To all 'wh-0m t may concern:

Be it knownthat we, RICHARD F. Lorna and JOHN IV. NYsTnoM, of the city and county of Philadelphiaand State of Pennsylvania, have invented certain new and useful Improvements in Steam-Engines, `of which the followinofis a full, clear, and eX- act description, reference being had to the` y accompanying drawings, which form part` of this specification and in which- Figure l represents a viewl in perspective of one of our double engines applied to driv-` ing a screw propeller. e F ig.` 2 is a transverse section through the condenser, bed frame, and air-pump of one of the steam cylinders.- Fig. 3 is a longitudinal section througli-the air pump and its valve chests. Fig. 4 1s a horizontal section through the steam cylindersand thesteam valve chest. Fig. 5 is a vertical longitudinal section of the saine, and Fig. 6 `is a side view of the steam slide valves. h f

Our improvements are peculiarly applicable `to that class `of marineY steam engines which are employed to drive screw propellers and which it is desirable should occupy the smallest space compatible with a due degree of strength and ellicient action, and a free access to the several parts for repairs and adjustment; where also it is desirable `that the engine should work at a high speed in order to drive the screw propeller at a sulficient velocity without the employment of' gearing, and at the same time to obtain a. large amount of duty from an engine of comparatively small size and light weight.

` Our improvements consist, first, in constructing and arranging the condenser and airpump whichappertain to each steam, cylinder in such manner that they shall constitute the columnsby which the cylinder is supported; second, in the construction `and arrangement of the valves of' twosteam cylinders working in connection, whichfis such that the cut-ofi'.1 valve of one cylinder `is actuated by the valve rod or valve of the other cylinder; third, in the construction and ar` rangement of the air pump valves, which is peculiarly applicable to engines running at a high velocity where it is essential that `these valvesshould close quickly.

In the double cylinder propeller engin represented `in the accompanying drawings A, is the bed-framewhich is cast hollow as shown in section at Fig. 2 and is bolted fast to the keelsons or timbers ofthe vessel. The

condensers of the` two cylinders are mounted upon the one side of this bedframe while the. air pumps are mounted upon the opposite side. The condensers B have the form of a hollow cylinder open at .the top and bottom; at their lower extremities they are secured tothe `bed frame and at their upper `to Vflanges or earsC cast upon-thesteam cyl-` inder. `These condensers are each fitted with arose adJutage a through which the injection water is introduced. The hot and y Y cold water pumps D D"arecast fast to the a condenser, and their plungers are connected `with the cross-head Eof'the steam piston Vrod F. Theair pump barrel Gr is cast in one piece with its valve chests H H andside-` pipes I. The barrel is prolonged above the head as represented at b to matchthe condensers at the oppositeside of the bed frame,

and the .upper extremity of,` this prolonged portion is secured to a flange or ear C 011` the steam cylinder J. The condenser `and air` pump thus constructed from the columns .on which the steam cylinder `J is supported,

while the hollow bed frame forms the cisy tern or well in which the water of injection' and condensation collect and by "which they are conducted to the air pump.

The steam cylinders VJ J are each mounted upon and secured to the upper extremities of `their appropriate condensers B and air pumps G; they have also cast fast to them the steam valve chests K and the `passages c, c which convey the exhaust steam to `the upper extremity `of the condenser.. Each cylinder is fitted with a piston M, piston rod l F, cross -head E, and connecting rod L which latter takes hold of the pin `of a crank I N secured to a crank shaft O beneath. The

cross-head is steadied by guides secured to 4thewinner faces of thecondenser and air pump.

Each cylinderis fitted with an` appropriate steam slide valve P which is moved by an appropriate `eccentric secured to the the motion of the valve are made to move over the steam and exhaust ports of `thevalve seat. The face of each valve slides upon the valve seat, while theY back of each valve crank shaft of the engine, and traverses forms a seat towhich a supplementary slide valve L is fitted by whose movement the steam passages f of the steam slide-valves are closed at the proper moment to cut ott the admission of vsteam to the cylinder. The supplementary or cut-off valve of each cylinder is connected by a link and moved with the steam slide Valve of the opposite cylinder, and as in thisvexample the cranks and eccentrics of the two cylinders are set at right angles with each other, the cut-ott' valve is moved with greater speed while its appropriate slide valve is moving with'least speed or is almost stationary. rlhis method Vof Varranging' and working the valves is extremely advantageous in cutting ott the steam as the operation is effected with rapidity, while it ispeculiarly applicable to fast moving` engines where it is desirable to employ the least complex and most simple machinery.

As it is important to be able to work the steam at full pressure throughout the' whole length of the stroke of the piston, apertures Y 0 0 are made in the sidesof the steam valves,

which are closed by suitable slide valves z' i; these valves are connected with rods fu which pass through the valave chest and are litted to screws t, t, or other hand gear by means of which they can be moved or kept at rest in any desired positions. When the engine is to be worked at full pressure these supplementary valves are adjusted by the engineer in such positions that the apertures 0 0 of the steam slide valves are uncovered throughout their whole stroke thus permitting the steam to enter through these apertures when those at the back of the steam vvalves are closed by the cut oil" valve 7L.

The air pumps of the engine represented in the accompanying drawing are double acting. Their piston rods y' are connected with the extremities of the cross-heads of the steam piston rods, so that as the latter are moved to and fro the air pump pistons are moved in a corresponding manner. Each air-pump barrel is litted with two valve chests, one H being` situated near the bottom of the barrel, while the other H is them, and each is secured to a tubular stem which traverses upon a stationary spindle p. The prompt closing' of each valve is insured by a helical spring r coiled upon the stationary spindle and concealed within the should be Vgiven to allow the water, whichY may be drawn therein when the valve drops, to pass out freely as the valve opens, this is eil'ected by perforating the tubular stems as represented at s in the accompanying drawings.

portant requisites in steamers and it is believed that an engine of this arrangement and construction attains this requisite in a higher degree than any condensing engine heretofore in use. lVhile it excels in this respect it is evident that such an engine will not weigh as much as others whose members are arranged in the usual manner, for in this engine the ordinary columns for supporting the steam cylinder are dispensed with, and the condenser and air pump are made to supply their place, as well as to do their own peculiar duty in the condensation of the steam and the production of the vacuum. This economy of weight in connection with the corresponding economy of space is all important as any saving in the weight and space occupied by the machinery increases in a corresponding manner the capacity of the vessel for carrying freight.

`What we claim as our invention and desire to secure by Letters Patent isj l. The construction and arrangement of the columns by which the steam cylinder is connected with the bed frame in such manner that they constitute the air-pump and Economy of space is one of the most im-' condenser substantially as herein set forth.

R. F. LOPER. J. WV. NYSTROM.

l/Vitnesses H. C. MEYER, STEPHEN H. SIMMONS.

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