US336924A - Steam-valve gear for duplex steam-pum ps - Google Patents

Description

(No Model.) 2 sheets-'sheet 1.

J. s. KLEIN. y

STEAM VALVE GEAR FORl DUPLEX STEAM PUMPS.

No. 336,924. Patented Mar. 2, 1886. I

(No Model.) 2 Sheets-Sheet 2.`

J. s, KLEIN. l

STEAM VALVE GEAR POR DUPLEX STEAM PUMPS. No. 336,924. Patented Mar, 2, 1886,.

llilin l NITED STATES.

" ATENT trice.

JOHN S. KLEIN, OF OIL CITY, PENNSYLVANIA.

`:EPLECIFICATION forming part of Letters Patent No, 336,924, dated March 2, 1886. Application tiled September 11, 1885. Serial No. 176,805. (No model.)

.T0 all whom t may concern:

Be it known that I, JOHN S. KLEIN, a citizen of the United States, residing at Oil City, in the county of Veuango and State of Pennsylvania, have invented certain new and useful Improvements in Steam-Valve Gear for Duplex Steam-Pu mps; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to steampumps; and it consists in improvements on the valvegear for duplex steam-pumps.

My invention is shown in the accompanying drawings, as follows: Figure l is a perspective View of a duplex steam-pump having thereon my improved valve-gear. Fig. 2 is a side elevation of the valve-gear. Fig. 3 is a perspective view of one of the rocker-arms and the cam by which it is operated. Fig. 4 is a transverse vertical section through the bed or frame and piston-stems, and shows the valve-gear in end elevation. Fig. 5 isa top or plan View of the valvegear with the rockerarin sleeves in horizontal section.

A A are the steam-cylinders. G G are the pump-cylinders. F F are the piston-rods. a a are the steam-valve stems. B B are the rocker-arms, which move the steamvalve stems a and a, respectively. C C are the journalsleeves of the rocker-arms B and B, respectively. D D are the cams which move the rocker-arms B and B', respectively. E E' are cam-followers, which are attached to the piston-rods F and F, respectively, and serve to move the cams D and D', respectively. I is the journal-pin of the rocker-arms, and His a hub connected with the bed, which holds the 4o j ou rnal-pin l.

The construction and operation of my invention are as follows:

The two pumps are operated alternately, and the steam-valve of one is operated from the piston-stem of the other-that is to say, one pump makes a full stroke one way, while the other stands still, and as it completes said stroke it opens the steam-valve of the other pump, and it makes a full stroke the other way while the first pump stands still. Connected with the journal-sleeve of each rocker-arm is a cam, which lies above the piston-stem of the opposite pump. Thus the rocker-arm B, which moves the stealnvalve stem a of the pump A G, is connected with a cam, D, which lies over the piston-stem which moves the valve-stem a of the pump A G, is connected with a cam, D, which lies over the piston-stem F of the pump A G.

Fig. 3 shows the construction ofthe rockerarm B, its journal-sleeve C. and the cam D, and it will there be seen that these parts are all formed of one piece of metal; but this is not essential. The other rocker-arm and cam are constructed in the same manner, and are counterparts of those seen in Fig. 3, except that the cam is reversed. The journal'sleeves of both are notched or cut away, so that the two parts can each span the hub H, one reaching around the hub on one side and the other on the other side. This is clearly seen in Fig. 5. By this construction each rockerarm has a bearing on the pin I on each side of the hub H. This is simply for thepurpose of giving a long iirm bearing, and it gives a bearing opposite the connection ofthe rockerarm'with the valve-stem; but of course this is not essential. The two cams stand, when in place, reversed-that is, the slot in the cam D curves up at the ends, and that of D curves down. The cams are rocked by the reciprocal action of the cam-followers E E', which are connected with the pistonstems F and F, respectively. The said cam-followers consist of a head or block connected with the pistonstems and bearing friction-rollers which lieiu the slots of the cams.

The cams D D constitute an essential part of my invention, as by them the admission of steam to and cutting of steam oft from the cylinder of one pump is effected by the action ofthe other pump. It is comlnon in duplex steam-pumps to move the steanrvalve of one pump by the action ofthe other pump through the medium of a rocker-arm and a connectingrod. With such a valvegear there is no point in the stroke of the piston in which there is no movement of the steam-valve it actuates. One ofthe results of this construction is, that where the pump is working light, as in draw ing air from a conduit as it is flling'with iluid,

Fot` the pump A G', and the rocker-arm B,

rco A it will not make full strokes, but short, rapid ones. Another objection to such a valve-gear is, that after a piston has completed its stroke no cut-off of steam occurs until it is time for that piston to move back again. In other words, the valves are moved from one end of their stroke to the other at one movement, so that when they stand they are admitting steam to the cylinders at one end or the other. In some cases this is not a disadvantage, while in others it causes a great consumption of steam.

By the use oi' my rocking cams D D, I overcome both the above objections, for, in the first place, they have a straight space in their slots,which allows the pistons to move without moving them, and they can only be moved as the pistons are beginning or ending a stroke, and, in the next place, when constructed as shown they move the valve twice to complete one stroke or traverse ofthe valve. Thus, for exa1nple,when the piston F starts to move, it will iirst move the cam D', so as to close the valve of the pump A G, and then, as it completes its stroke, it will again move the cam D in the same direction it did at iirst, and this will open the valve of the pump A G. This latter feature where not wanted wiltbe dispensed with by omitting the lower bar ot' the cam Dl and the upper one of the cam D, or the inclined faces on said hars. To a full understanding of the action ofthe valvegear, I will describe its complete operation.

Beginning with the parts in the position shown in Fig. l, the piston-stem F is just completing its stroke toward the right, and the cam-follower E is just impinging upon the lower inclined face at the angle ot' cam D. As this stroke is completed, the cam D is tilted down at its right end. This rocks the arui B to the right and opens the valve of pump A G, so as to admit steam to the left of the cylinder A. This action starts the pistonstem F on its stroke toward the right, and as it starts the canrfollower E will tilt the cam D down at its left end and rock the arm B to ward the left, and thus close the valve of the pump A G. Then the "piston-stem F is about completing its stroke toward the right, the cam-follower E -will strike upon the upper inclined face at the right end of cam D, and tilt the said cam again in the same direction as before, and move the valve ot' the pump A G still farther to the left, which will open the part at the right end ofthe cylinder A, and start the piston-stein F' on its return-stroke, and as it moves to the left it tilts up the right end ot' the cam D and closes the valve of cylinder A.

From the foregoing it will be seen that if, as above stated, the cams were so formed that there were no cam-faces on the upper side ot' cam D nor on the lower side of cam D, the valves would only be moved once in either direction in making a full traverse, and hence they would have to be so formed that they would be admitting steam to the cylinders all the time, either at one end or the other, just as is common in the constructions heretofore in use. So it will be seen that I can so construct my cams as to either cut ott' the steam from the cylinders while their pistons are at rest or not, as desired. It will also be observed that in either case the cams will not be moved, and therefore the valves will not be moved except as the pistons are at the beginningr or finish of their strokes, and therefore it, will be impossible for the pumps to run with short quick strokes, for the pistons must make full strokes in order to eli'eet a cut-oit' or admission of steam.

What I claim as new is- I. In a duplex steanrpump, a valve-gear consisting of the combination ot' a rocking cam which consists of a bar pivoted at its middle and having a Cain-slot formed, as shown, with upper and lower cani-faces at each end and a dwell between the ends, arranged adjacent to the piston-stem of each pump, a cam-follower on each piston-stem, by which said cams are rocked as the said piston-stems reciprocate, and rocker-arms connected with the pivot of each of said cams, and with the valve-stem of the opposite pump.

2. In a duplex steam-pump, a valve-gear which consists of the cams D D, joui-nah sleeves C C', rocker arms B B', and cam-followers E E, combined and arranged to operate substantially as and for the purposes set forth.

3. In a duplex steam-pump valvegear, the combination, substantially as shown, of the cam-followers E E', connected with the pistons F F, respectively, and the two rocking gears formed, respectively, of the cam D, rocking sleeve C, and arm B, and the cam D', `journalsleeve C', and arm B', and journaled on the common pivot I, and operated from the piston-stems F F, and connected with the valvestems a a', respectively.

In testimony whereot I atix my signature in presence of two witnesses.

JOHN S. KLEIN.

Witnesses:

JNO. K. HALLooK, RoBT. H. PORTER.

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