US247006A - John h - Google Patents

Description

' (No Model.) J. E. BLAKE.

GUT-OFF VALVE GEAR.

Qd Sept. 13,1881'.

tateg R INVENTOR ATTORNEYS.

UNITED STATES PATENT OFFICE.

JOHN H. BLAKE, OF BATAVIA, NEW YORK.

oUT-oFF-VALVE GEAR.

SPECIFICATION forming part of Letters Patent No. 247,006, dated September 13, 1881.

Application filed January 24, 1881. (No model.) A I To all whom it may concern:

Be it known that I, JOHN H. BLAKE, of Batavia, in the county of Genesee and State of New York,have invented a new and Improved Cut-Oft`-Valve Gear, of which the following is a full, clear, and exact description.

The object of this invention is to increase the sensitiveness of the engine-governor and to make the action of the cut-off devices more prompt and decided.

The invention consists of two slide-valves, one at each end of the cylinder, each having a separate steam-chest, into which steam is admitted throughout the whole stroke of the engine, the point of cut off being regulated by rotary valves that are placed in supplemental steam-chests over each slide-valve; and it consists, further, of a hydraulic cylinder designed to be operated by water under pressure, provided with suitable valve and piston, which cylinder forms the connection between the governor and rotary or cut-off valves and facilitates and regulates the action ofthe latter; andthe invention further consists ofimproved mechanical devices for operating the parts, all of which will be hereinafter described.

Figurel is a longitudinal section al elevation, showing the improveddevice applied to an engine-cylinder. Fig. 2 is an enlarged sectional side elevation ofthe hydraulic cylinder and its immediate connections. Fig. 3 is a vertical sectional elevation on line x x, Fig. l. Fig. et is an enlarged cross-section on line y y, Fig. 3.

Similar letters of reference indicate corresponding parts.

In the drawings, A represents an enginecylinder, and A'4 A3 the piston and piston-rod, respectively.

The valve-gear consists of two slide-valves, B B', one at each end of the cylinder, and each having a separate steam-chest, C, linto Awhich steam is admitted throughout the whole stroke, and having a common shaft or stem, C'. The steam inlet and exhaust ports from the steam-chests C into the cylinder A are shown at a, a', and the exhaust -ports from steamchests C are shown at b b. 'lhese slide-valves B B' are designed to be moved by means of the usual mechanisms connecting their stems C' with the crank-shaft of the engine.

The point of cut off is regulated by the two hollow rotary valves D D', that are placed in a supplemental steam chest, E, respectively over each slide-valve B B', said steam-chestE having communication with the valve steamchest O by means ot' the ports cc' immediately below said valves D D'. These lrotary valves D D' make each revolution in time with the en gine-stroke, and are cut away on their faces, as shown at d', forhalf their diameter less the amount ofthe width of their respective ports cc', and they occupy opposite ends of the steamchest E, and are firmly keyed, as shown at d, or otherwise secured, with their faces d' in opposite directions to the shaft F F', which extends out through one end of -said steam-chest E. Each rotary valve D D' is provided with an annular ange, f, on that end which is toward the end of the steam-chest E, of a width sufficient to fill the corresponding semicircular space g between the end of said steamchest E and the valve-seat E', whereby any lateral movement ofa valve, D, on its seat is prevented. r1`hese valves D D' are retained in line with their shaft F F' by the steam-chest ribs h,that encircle said valves DD', as shown,

- and they may be kept seated at all times by means of the adjusting-plates G Gr, that are placed between their upper surfaces and the top of the chest E, and are'held by the setscrewsk k, which are entered through the top ot chest E. Instead of being keyed to the sha-ft F F', these valves D D' may be held thereon by forming a collar of square crosssection lon Ithe said shaft F F' 5 or the shaft itself may be left square and fitting said collars in corresponding square openings in the ou-ter end of each valve D D', the openings in the valves to be a little larger than the collars or square portions of the shaft F F', in order to permit the valves D D' to seat themselves as they wear without disturbing the valve-shaft lOO sleeve H, and is connectedto the section F' by a stud, n, projecting from said section into a spiral slot, fn', in said sleeve H, and extending around it for about one-halt` of its diameter. Hence it will be seen that any longitudinal movement of the sleeve H will produce rotation of the section F' of the rotary valve-shaft, and consequently of the valves.

The longitudinal movement of the sleeve H may be produced by the governor through proper connecting-rods inthe usual manner; butin this instance I make use of the hydraulic cylinder I, vset immediately over and parallel with the rotary valve-shaft F F' 5 and to the piston-rod I2 is keyed one endoi' avertical arm, I3, whose other end embraces or is otherwise connected with the sleeve H, as shown, so that any motion communicated to the piston I' will be transmitted to the sleeve H. Thishydraulic cylinder I is provided with the ordinary D slide-valve, K, whose stem K' is connected with a governor, L, (indicated in dotted lines, Fig. 1,)by the right-angled lever L', as shown. The upper arm of this lever L' is provided with a slot, 0, or several holes, so that the point of attachment for the connecting-rod L2 from the governor L may be regulated according to the sensitiveness desired.

The connecting-rod L2 is made in two parts, with screw-threaded ends, and a nut, L3, is xed thereon, by means of which said rod Lz may be lengthened or shortened to bring the hydraulic valve K in the center of its seat in -relation to any desired height of the governor 35' be driven by a train of gears from the main shaft or by other suitable device. v

It is proposed to use in the hydraulic cylinder I, to produce the desired motion ofthe piston I' and its connections, water under pressure. This water-pressure may be obtained from a boiler by connecting therewith a pipe con siderably below the water-level of the boiler, and connecting the other end of said pipe, as represented at p, with the valve-chamber g of the cylinder I. This connecting-pipe p should be of sufcient length to insure the condensation of any steam that may enter or form in it or for the purpose of such condensation the said pipe p may be passed through the cold feed-water.

The valve K of the hydraulic cylinder I being adjusted to the center of its seat when the governor balls are at a height necessary to produce the desired speed, any variation will cause the prompt extension or reduction, as the case may be, of the point of cut oft.

One particular advantage of this system of governing is that so long as the engine is running at the desired speed the valve K ot' the hydraulic cylinder I will remain in the center of its seat, and, as water is not compressible, will retain the piston I', and consequently the height of the governor varying only long enough to produce the proper point of cut oli', and then lockin g it there.

Another advantage of this system is its sensitiveness, as the governor-balls have only to move a small slide-valve, K, and the power of the device can be increased toany desired extent by increasing the size of the cylinder I. When the parts are in the position herein shown the rotary valve D' is just commencing to open its port c' and the valve D has just closed its port c, and the steam, as it is admitted through' the supply-port S into the steam-chest C, passes through the port c' into the steam-chest C of the sliding valve B', and the valves B B' moving synchronously, the steam enters through port a' into cylinder A in rear of the piston A', while the exhaust escapes through port ce into and out of the exhaust-port It. Onthe return-stroke the steam enters through ports c and a and exhausts through a'. if a rotary valve, D D', were setso as to commence admitting steam to the slidevalve chest C just as the stroke of the engine commenced, the steam would be admitted full stroke; but if this rotary valve were advanced about one-half of a revolution, or the amount that its face was cut away, then it would commence to admit steam to the slide-valve chest G just as a valve,B B' ,covered the steam-port for the return-stroke. Ot' course, the full steampressure would be in the steam-chest C of the slide-valve until the port was opened by that valve for the next stroke;IA but by that time the revolution of the rotary valve would have cut oit` steam, and the only steam available for the cylinder A would be that remaining in the slide valve chest, which steam would be but of small amount. These two points of cut off, as described, would be the longest and shortest, respectively. Between these two points of cut oft' any one may be obtained by advancing, the rotary valves D D more or less, as may be desired.

This system of governing is not limited to automatic cut-oft' engines, but is applicable to `throttling and marine engines, and, in short,

to all purposes to which a governor may be applied.

Water-pressure may be obtained for the hydraulic cylinder from other sources than-.the boiler, and when convenient oil or other duid vmay be substituted for water in the said cylinder.. As in practice a longer cut-off than half-stroke would probably not be necessary, the faces d' of the rotary valves D D could be made of proper width to produce this effect, and thus reduce the time the slide-valves B B would be under pressure.

Having thus described myinvention, I claim as new and desire to secure by Letters Patentl. An improved engine-governor and cut-off constructed substantially as herein shown and described, consistiu g ofthe rotary valves D D' in supplemental steam-chest E, rotary valvecut-oii", at any point it may have assumed, the stem F F', coupled by sleeve H, hydraulic cyl- IOO IIO

inder with piston, piston-rod, and arm I I' I2 I3, and valve K, lever L', connecting-rod L2, and governor L, arranged and operating as set forth.

2. In an engine-governor and cut-off, the combination,with the hollow rotary valves D D', of the valve-stem F F', provided with feather m andstudn,andcoupling-sleeveH,providedwith straight slot m' and spiral slot n', substantially as herein shown and described, whereby the advance of the said rotary valves may be accomplished, as set forth.

3. In an engine-governor and cut-0H, the combination,with the supplemental steam-chest E, provided with semicircular spaces g, of the rotary valves D D', provided with corresponding flanges f, substantially as herein shown and described, said flanges preventing lateral motion of said valves, as set forth.

4. In an engine-governor and cut-off, the combination,with the rotary valve-stem F F', coupling-sleeve H, and hydraulic cylinder, piston, and piston-rod I I' l2, of the arm I3, substantially as herein shown and described,whereby the movement of the said piston is transmitted to the said rotary valve-stem, as set forth.

5. In an engine-governor and cut-off, as a means for transmitting the motion of the governor to the cut-ofi valves, the hydraulic cylinder I, provided with piston and piston-rod I' I2 and valve K, in combination with the governor L, lever L', and adjustable connectingrod L2, substantially as herein shown and described.

6. The combination, with the cylinder A, of steam-chests C, containing slide-valves B B', steam-chest E, contanin g rotary cut-oft' valves D D', rotary valve-stem F F', coupled with sleeve H, hydraulic cylinder, piston, pistonrod, and arm. I I' I2 I3, respectively, lever L', connecting-rod L2, and governor L, arranged substantially as herein shown and described.

7. In an engiuegovernor and cut-olf, the combination, with the sectional rotary valve-stem F F', provided with feather m and stud n, of the sleeve H, provided with straight slot m' and spiral slot n', substantially as herein shown and described.

JOHN H.' BLAKE. Witnesses:

G. E. FISH, F. E. NORTH.

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