US26654A - Matthew oridgb - Google Patents

Description

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ILPETERS. PHOTO-UTMOGRAPHER. WASHINGTON. D4 C.

' `do herebydeclare that the following is a STEAM-VALVE; y y

specification afnemers meenam. esem, rated Januar@ To 'all Vwhomiii/moby concern: i, y l

Be'it knoivn that I, MATTHEW CRiDGE, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have inventeda` new and :useful Improvement; in Variable Cut-O' Governor-Valves for: Steam-Engines; and I full, clear, and exact? description ofthe construction and operation of? thesame.

The nature of my, invention consistsin a novel arrangement of a` revolving cylindical or cupvalve, which` is capable` of cutting off` the steaniat; any point in the stroke of an engine, being connected With the governor of the engine so, that the point of cut-off is controlled by the action` ofthe said governor, wherebyl thecharge of steam admitted` into'thecylinder, is regulatedxor varied so, as toimeet any changes in the resistance or load of" the engine, or any variationszun the steam pressure ;-thus regulating the` speedrof t-he engine. i

'llo enable others skilled in the artl to make and` use in vinvention If Will proceed to de-v scribe its construction andl operation, taking) k reference to the accompanying drawings making a part ofl this specification, andA in Which- 1 Figure l, is averticali section ofitlie. valve andl governor;l `igs. 2, 3,4 and.` 5` are de-` tails andV Figs. 6 and? diagrams` to which special reference Willbe had in the following description.

In all the i reference are marked on alike parts.`

A is the valve; B is the valve seat, formlinga shelll which incloses the valve; C is the outer casing, into which the valve seat is fitted; D is the governor seton the casing.

shown in Fig. 5, has tvvo triangular steam ports au in it, as fully seen in Fig. 6, Which is a diagram of the outer cylindrical surface of the valve, laid into a plane. The valve seat B, of which a separate view is shown in Fig. t, has also two` steam ports b, b,

in it, which are of a similar triangular shape, but reversed to those of the valve, as is fully seen in Fig. 7, Which` is a diagram of the cylindrical (inner) surface of the seat, laid into a plane. The valve seat Wit-h the valve inclosed, is also shown in Figs. 2 and 3, in which the valve seat is represented in side view, taken at right angles to that shown in Fig. 4; and the valve shown in figures i the saiiie characters off The valve A, of which a separate view is viz.: Fig. 2 showing its position whenith 1 ports a. and b` are nearly closingjloiy cuttingM off the steam; and Fig.l3, ilvheni the poitsiarre..`

stein-la. `"llhe valvestem andvalve are.herebyj` made toy-,revolve witlithegovernor, il

perf-w l l tivo ediiferent positions. in i relationto `the se opening, or commencingftoadmit thelsteamw f u This latter position"ofitheivalve. also clorre-` L sponds to that `shown infthe.sectionliigal.l

The arrovv y indica-tes the directioninwhioh,

thevalve turns. The outerrcasing C.; is made i to -leaver an annulari` space; c, between it; anda the seat, which1 communicates with thepasf` sage d.

The stem? e ot-theivalve througlif; the stuiiing box f` in the toprof thek casing@ and is connected with thekgovernorfin suoli-i a manner` as to be raised` or lotveredfby thei actionfofthe sameq` The` governor D represented; iai Fia i `laf `of the Well lmoivnCQIlSt-iuction Oballileversp With toothed segments (h,`;]a)\gear.ing into `the teeth g` at the `valvesteune.f l m iS alpin through `the valvestenifpaSSIis-r L through the openings o"` oa fing@ they. governon` The Openings 0. o, are made Slot-ted pendicular direotionpfonthe puirpose off` al- (10ML` playin it,so.asl nottoiiinpede theraisin on lowering ofthe valveistem (Withfthe va.`

lowing` the pin m alsutlicient `zuppa by the action of the,governor.`

. a isa scale, fastened tothe governor-fnaine i i wliich is located, and divided so,i .that the i.

` is raised by the governor,` aiidthusvindicatesl pin m` vshows the` height to` which, tlievralvei the degree 0:6 cutfor.correspondingtb that@ y i,

height. Thusif the pin is;` opposite the gfi `ure g of the` scale,.the engineis iworkgingwiuthi i i the steam cuteol' at fiv,e-eighths-ofwitsfstroke,i` Thegovernor receives its ambien ha` the; bevel Wheels z', c' and the shaftl, which com-i municates With the engine shaft by vvheel gear or any other known mechanical means,` i

suitable for the purpose.`

The operation of the described `valve ar rangement is very simple. The steam enters into the valve at the arrow `(Fig. l), and

passes when the ports a. a and b b are open,

through the saine into the circularspace10,1,`

and from there, through the pipe or passage d, to the steam chester `distributing valve of the cylinder.

By reference to diagrams 6 and 7) it will be seen, that the rig. a (aaa Ligero the openings of the-ports or the adniissionof y the steam takes place,iwlien the perpendicu-` lar sides 1 2 of the valve ports' ci pass over the corresponding sides 3 4 of the seat ports, and that the point of opening is always the same or invariable, whether the valve be raised more or less by the governor. The closing of the ports or the cutting off however takes place when the inclined sides 5 6 of the valve ports a pass over the inclined sides 7 8 of the seat ports b, (see Fig. 2), and it is evident that this will be the later the higher the valve is raised, and the sooner the lower its position is. The degree of cut-olf will therefore be perfectly controlled by the action of the governor.

- It is obvious, that the revolving motion of the valve (when provided with two ports, as herein represented) has to be such,` as to make one complete revolution for each double stroke of the iston of the engine or for each revolution of its crank shaft ancl the governor from which the motion of the valve is derived has consequently to be driven with precisely the same speed. The valve has further to be set, in relation to the piston of the engine in such a way, that the admission of the steam, (i. e. the opening of the ports a and ZJ) takes place exactly at the beginning of the stroke of the same.

As the steam acts in the described valve as well from above as from below, it is balanced, with the exception of a slight pressure upward, acting under the valve stem. This pressure has the tendency of keeping the balls of the governor down or counteracting the centrifugal power of the same.

If the described cut-off and governor arrangement is applied to a fast running engine, the governor will run with an extraordinary speed, and it becomes necessary to counteract the centrifugal power of the same to some degree. This is partly done by the above mentioned steam pressure. But in addition thereto, I use springs p, p, fastened to the stem 7c of the governor, and connected with the ball arms g, g, by the screws 7', 1^, and adjusting nuts s, s. By these means I am enabled to regulate or change the speed of the engine at pleasure. Thus, in order to increase the speed of the engine (its load remaining the same) Iadjust-the springsby means of the screws and nuts-so that they are more strained, whereby they will counteract the centrifugal force of the balls with an increased power. In consequence thereof, the balls will adopt a lower position, whereby the valve is raised, and admits steam into the cylinder of the engine for an increased portion of the stroke. The charge of steam per stroke being thus increased, and the load remaining the same, the engine will necessarilyy run with an increased speed. Y

The number of ports in the valve and valve seat) is not :necessarilyV confine to twog/but may be changed to three, four or more if this is done, the speed of the valve must be changed accordingly. Thus in using four steam ports in the valve, the same has to be made to revolve only once for two revolutions of the crank shaft of the engine in using 3 ports, the speed of the valve has to be only two-thirds of the crank-shaft.

The cut-onz governor valve herein represented has the advantage that it is capable of changing the degree of cut-olf from the smallestfraction of the stroke to full stroke; that it is extremely simple, effective, and easil kept in order.

`I o not claim broadly the arrangement of a cup valve, so as to revolve and at the same time to ascend and descend by the action of the governor, as similar arrangements have been made before; but Y What I do claim and desire to secure by Letters Patent is Providing in such an arrangement e. of a revolving and ascending and descending cup valve) the valve A and its seat B with port openings, having inclined edges (5 6 and 7 8) so that the steam is cut off by them variably and controlled by the governor, substantially in the manner and for the purpose herein set forth. Y

MATTHEV CRIDGE.

Witnesses:

G. H. FICHREN, AUG. HARTJE.

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