US354091A

US354091A - bicknell

Info

Publication number: US354091A
Authority: US
Publication date: 1886-12-14
Anticipated expiration: 1903-12-14

Description

(No Model.) 3 Sheets-Sheet 1. W. A. P. BIOKNELL.

PUMPING ENGINE. No. 354,091. Patented Dec. 14, 1886.

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(No Model.) 3 sheets-sheet?, W. A. P. BICKNELL. PUMPING ENGINE. No. 354,091. Patented Deo. 14, 1886.

Ihnen/@irs 3W t e e h S Q t e e h S 3 L L E N K O TI- DD .B AW W (No Model.)

PUMPING ENGINE.

Patentef Deo. 14, 1886.

W W l N. Finns. Pham-mhugnpher, washingtun. D:C,

UNTTED STATES PATENT Ormea,

VILLIAM A. P. BIOKNELL, OF NEV YORK, N. Y., ASSIGNOR TO VILLIAM A. PERRY AND CHARLES C. VORTHINGTON, BOTH OF SAME PLAGE.

PUlVlPlNG-ENGlNE.

SPECIFICATION forming part of Letters Patent No. 354,091, dated December 14, 1886.

Application filed August 4, 1886. Serial Eo. QtELD. (No model.)

T @ZZ whom it may concern,.-

Beit known that I, XVILLIAM A. P. Bici;- NELL, a citizen of the United States, residing at New York, county ot" New York, and State of New York, have invented cert-ain new and useful Improvements in Pumping-Engines, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

This invention relates to that general class of engines which are known as direct-aeting, and particularly to an engine of-this class which is designed for pumping liquids, or, in other words, a direct-acting pumpingengine. lu an engine of this class, the same as in other classes of engines, it is of course desirable, for the sake ot' economy, to use the steam expansively. rllhis has heretofore been accomplished in some cases by the use of compound cylinders, and in some cases by the employment of one or more auxiliary or compensating cylinders and pistons, which is or are arranged to act in opposition to the main steam piston or pistons during the irst part of the stroke ofthe engine,a nd in conjunction therewith during the last part ot'y the stroke, as shown and described in the United States Letters Patent granted to C. C. Vorthington, January 29, 1884, No. 292,525, and in several subsequent patents to the same inventor.

lt is the object of the present invention to provide means by which the steam can be used expansively in a direct-acting pumping-euz gine withouttheemploymentofcomponnd cylinders or other means lfor securing an even distribution of the power throughout the entire stroke, and yet without resulting` in a spasmedic or noisy action of the engine or an irregular discharge of the liquid from the `forcemain.

My invention is based upon the discovery that where the force-main of the pump is of sufficient length the moving column of liquid in the force-main can, by reason of itsinertia, be made to perform the same or substantially the same function as a fly-.vheel--that is to say, the column of liquid can, by reason of itsinertia, be made to absorb or take up the excess ot' power developed by the engine during the tirst part ot` the stroke, when the pressure in the steam cylinder or cylinders is greatl est-,and will then give up this absorbed power,

the stroke,when the pressure in the steam cylinder or cylinders is reduced by reason of the expansion of the steam. ln order that the column'in the main may perform this function, it is of course necessary that the usual air-chamber which is located at or near the force-chamber should be omitted.

As a t'ull understanding of my invention can be best given by an illustration and description ot' an engine embodying the same, all further preliminary description of the invent-ion will be omitted and a description of such an engine given, reference being had to the accompanying drawings, in which- Figure l is a side elevation, partly in section, of a single direct-acting pumping-engine embodying my invention. Fig. 2 is a sectional clevatiomupon au enlarged scale,of the steam end of the engine, or engine proper,and a part ofthe water cud ofthe engine, or pump proper. Fig. 3 is a sectional elevation, upon a still larger scale, of the cataract apparatus for controlling the operation ofthe main steamvalve. Fig. 4 illuszratesa moditicatiomwhieh will be hereinafter explained; and Fig. 5 is a diagrammatic plan view illustrating the mauner in which the invention may be applied to a duplex pumping-engine.

Referring particularly to Figs. l and 2, it is to be understood that A represents the steamcylinder, and B the water-cylinder, of an ordinarysingledirect-actingpumping-engine. The piston C of thesteam-cylinder is connected directly to the plunger D of the water-cylinder by the pistonrod a, in the usual manner. The cylinder A is provided with the usual induction and exhaust ports,23,which are controlled by an ordinary slide-valve, 4. The Water-cylinder B is provided with the usual suction and force chambers, F G, the former of which communicates with the suction main H, and the Vlatter with the force-main K. The force-chamber G is not provided with the usual air-chamber to equalize the dow from the force-chamat a considerable distance from the pump with what I term an equalizer,77 which is arranged to exert a yielding pressure upon the column 0f water in the force-main at that point, and

so as to aid the engine during the last part of ber to the main, but the forcemain is provided.

IUC

. As shown in Fig. 1, it consists of an air-chamber, L, which is about the size of or slightly larger than the air-chamber usually located at the force-chamber. The distance which the equalizer` should be removed from the pumpthat is to say, the length of the column of liquid in the force-main between the equalizer and Y' the pump-will depend largely upon the diameter of the force-main, the size ofthe pump, the length of the stroke, the speed at which it is run, the head against which the pump is working, and the weight of the liquid being pumped. Assuming the liquid to be pumped to be water, the diameterof the force-main twelve inches, the diameter of the pump-plunger twenty inches, the length of stroke thirtysix inches, the number of strokes per minute forty, and the head two hundred feet, the length ofthe column between-the pump and the equalizer should be about live hundred feet.

The force-mainK will preferably be provided just beyond the equalizer with a checkvalve, 34, the purpose of which is t0 prevent the reaction of the column of liquid in the main beyond the equalizer, and also to prevent that part of the force-main from becoming emptied in case it should be found necessary to take the pump to pieces for any purpose.

Thevalve 4 of the cylinder A may be operated in any of the ways common in this class of engines. The valve-operating mechanism will, however, preferably be of the form shown, which will now be described. The valve-chest E of the cylinder A is so formed as to provide at its ends two small cylinders, b, into which fit pistons or plungers 30, which are connected by a rod, 31, and are arranged so that their inner ends abut against the opposite sides of a projection formed on the top of the'valve 4. The small cylinders b are provided with single induction and discharge ports l, which are controlled by a small slide-Valve, 5, located in a small steam-chest, e, on the top of the steamchest E.

Steam is admitted to the chests E e through the usual induction-pipes, 32 33, and, after being used in the cylinders A b, is exhausted into the usual exhaust-pipes, 10 1l. The inner one of the pistons 30 is provided with a rod, 12, which passes through the end of the steamchest and is connected to a small piston, 35, which works in a cylinder, c, located at the end of the steam-chest E. The cylinder cis filled with oil or other liquid, and is provided with a duct, 6, which extends from end to end ofthe cylinder, and is controlled by a cock or valve, 7, by which the duct can be opened to a greater or less extent, so as to regulate the circulation of the liquid from one side to the y other of the piston 35. In addition to the duct 6,the cylinder c is provided with Vtwo ducts, 8 9, which extend from the opposite ends of the cylinder, and open into the cylinder at points distant from its ends -about two-thirds of its length.y rlhese ducts are controlled by outwardly-opening check-valves 13 14, which are arranged as best shown in Fig. 3. The valve 5 is provided with a rod, 29, which passes through the end of the steam-chest e, and is connected to a short arm extending from a rock-shaft, 36, having a second arm, 37, the lower end of which is connected tothe piston- -rod a in any of the common ways.

The engine may be provided with .any suitable form of cut-oft' apparatus. The apparatus which is shown for this purpose is of substantially the same form as that shown in the Letters Patent No. 292,525, before referred to. It consists of two oscillating plugs or valves, 28, which are arranged in the induction-ports 2, and are provided with arms 27, which are connected by a rod, 26, which is in turn connected to a lever, 25, which is connected by a rod, 24, with the piston-rod a.

The operation of the engine thus organized is as follows: In describing this operation it Will be assumed that the engine is in operation and that the parts are in the position shown in Figs. 1 and 2, the engine havingjust completed its inward stroke. lt will be observed that just before the parts arrive in this position the arm 37 willhave rocked the shaft 36, so as to move the valve 5 into position to permit the steam to enter the inner one of the cyl-v inders b, and at the same time permit the steam already in the outer one of the cylinders b to be exhausted. As the steam enters the inner one of the cylinders b,'it will move the pistons 30 35 outward,\and thereby commence to shift the valve 4. This will take place just before or just as the piston C arrives at the end of its stroke, as shown in Fig. 1. As the pistons 30 35 are thus moved, the liquid in the cylinder c will be forced to circulate through the duct 6 from one side to the other of the piston 35, and the duct 6 being comparatively small, the liquidwill flow through it slowly, thereby preventing the pistons 30 35 from moving quickly, so as to shift the valve 4 suddenly. This slow movement of the pistons 30 and the valve will prevent the live steam from being admitted in front of the piston C before it has fairly come to rest, and will secure the necessary pause or dwell at the endl of the stroke, to permit the column of liquid between the pump and the equalizer to come to rest and the pump-valves to come to their seats Without slamming, and to prevent li'ndue strain upon the engine. JThe duration of the pause at the end of the stroke can be readily varied and regulated by adjusting the cock or valve 7 of the cataract apparatus, so as to permit the liquid to circulate more or less rapidly through the duct 6. The pistons 30,thus set in motion,will continue to move the valve 4 slowly until the valve commences to uncover the induction-port 2 at the IOO IIO

inner end of the cylinder A, so as to admit steam behind the piston C, to start it upon its outward stroke. As soon as this takes place, itis desirablethat the valve 4 should make the remainder of its stroke quickly, so as to fully open the induction-port 2 as quickly as possible. This is accomplished by means of the duct 8 and valve 13. It will be observed that during the first part of the movement of the pistons 30 35 the piston 35 covers the inner end of the duct S, but just as the valve 4 commences to uncover the port 2 the inner end of the duct 8 is uncovered by the piston 35, and this permits the liquid in the cylinder c to raise the valve 13 and flow freely through the duet 8 tothe other side of the piston 35, so as to offer very little resistance to the piston, and allow it and the pistons 30 and the valve i to be moved quickly bythe steam for the rcrnainder of their stroke.

As soon as the valve has been shifted, asjust described, the full pressure of the steam will be exerted upon the piston C, to start it upon its outward stroke, and the power thus developed willbe expended in starting and moving the column of liquid in the force-main. During the first part of the stroke, when the steam is acting at full pressure on the piston C, the power developed by the engine will be in excess of what is required to move the column of liquid at the mean or average velocity required, and the consequence will be that this excess of power will be expended in accelerating the velocity of the column, and thus the Column will,as the piston approaches the middle of the stroke, acquire a greater velocity than is required. This extra velocity will not be imparted to the whole-column, however, but only to that part of the column which is between the pump and the equalizer, and will result in compressing the air in the chamber L. After the engine has made a part of its stroke-say about olie-third, more or less-the valve 2S at the inner end of the cylinder A will arrive in position to out oft' the further admission of steam to the cylinder, and the piston C will proceed upon and complete its stroke under the expansive force of the steam already in the cylinder. As the steam expands in the cylinder,its pressure of course decreases, thus reducing` the power of the engine until, as it nears the end of the stroke, the power will fall below what is required to move the column of liquid in the force-main. That part ofthe column between the pump and the equalizer, having, however, been accelerated during the first part of the stroke,will, by reason of its inertia, aided by the decreasing power of the engine, continue in motion, but at a decreasing velocity during the last part of the stroke, and thus permit the engine to complete its stroke. During the last part of the stroke, and during the pause before the commencement of the next stroke, the air in the chamber L, which was compressed durin'g the irst part of the stroke, will expand, and thus maintain a uniform or practically uniform pressure at that point,and

secure a uniform flow of the liquid through that portion of the force-main beyond the airchambcr and a uniform discharge of the liquid from the force-main.

Fromwhat has been said itwill be seen that that portion of the column of liquid in the force main which is between the pump and the equalizer is made, by reason of its inertia, to perform the same function as a fly-wheel* that is to say, it takes up the excess of power developed by the engine during the first part of the stroke,when the power is greater than is required, and gives off this power during the last part of the stroke,when the power developed by the engine is less than is required. It will be seen, however, that this result could not take place it' the pump were provided with the usual air-chamber at or near the forcechamber, as in such case the excess of pressure ofthe steam at the commencement of the stroke would simply impart additional velocity to the pump-plunger, which would cause the air in the air-chamber of the pump to be compressed, but would not impart any additional velocity to the column in the forcemain. From this it would result that when the steam-pressure was reduced during the last part of the stroke by the expansion of the steam the air in the chamber would expand and otier the same or substantially the same resistance to the pump-plunger, and as a result the engine would not be able to complete its stroke.

As the piston C arrives at the end of its outward stroke, it will cover the exhaust-port 3, and be brought to rest in the usual manner by cushioning upon the small amountof steam confined in the end ot' the cylinder. Just before the piston C arrives at the end of its stroke the valve 5 will be shifted so as to open the port l, to admit steam to the outer one of the cylinders b, and the piston C will then make its inward stroke in the same manner as just described.

Vhen the engine is in operation, the column of liquid in the force-main may not, owing to its inertia, come to rest at once upon the conipletion of the stroke ofthe piston Gand plunger D, but continue to move in the main during the pause or dwellof the piston and plunger. This movement of the column will have a. tendency to draw the liquid through the pump, and will raise all of the suction and force valves, as indicated in Fig. 2; but the pause of the engine at the end of the stroke will allow time for that portion ofthe column between the pump and the equalizer to come to rest, so that the valves will come to their seats and notdbe slammed by the starting of the plunger upon its return-stroke.

It has already been stated that the pause or dwell of the piston C at the end of the stroke can be readily varied by adjusting the cock or valve 7 so asto permit the liquid in the cylinder G to circulate more or less rapidly from one side to the other ot' the piston 35. From this it follows that the cock or valve 7 IIO ' pose the cock 7 is provided with an arm, 15,

which is bifurcatedatits end and straddles a disk, 16,which is secured to the end of aslnall plunger, 17, which enters a small cylinder or chamber, 18, formed below the cylinder c, as best shown in Fig. 3. The chamber 18 communicates by a pipe, 24, with the force-main K at or beyond the equalizer. The disk 16 is provided with a spring, 19,which is arranged to act in opposition to the plunger' 17, and is of sufficient strength to just counteract the pressure which exists in the main when the engine is operating at its normal speed. From this arrangement it results that whenever the pressure in the main is increased beyond the proper point this increased pressure will be communicated to the plunger 17, and will overcome the tension of the spring 19 and operate the cock 7, so as to check the flow of the liquid from one side to the other of the piston 35, and thus lengthen the pause ofthe piston C at the end of the stroke. As soon as the pressure in the force-main is reduced, the spring 19 Will again open the cock 7. The Spring 19 is provided with an adj Listing-screw, 20, by which its tension can be regulated, as may be required. From what has been said it will be see that the Volume of air in the chamber L is,in effect,a cushion or spring-or, in otherwords, a yielding connection-interposed between that part of the column of liquid Which is beyond the air-chamber and that part which is between the air-chamber and the pump, its function being to permit the part of the column neXt to the pump to move at varying velocities without materially affecting the velocity of the part beyond the air-chamber. This being the ease, it is apparent that other means than the volume of confined air may be employed to effect the same result. For example, as. illustrated in Fig. 4, the'equalizer is in the form of an accumulator, and accomplishes the same result. As shown in said figure, the chamber L, instead of being filled with a body of air, is provided with a plunger,

A38, which is acted on by suitable weights, 39.

The action of the equalizer thus formed is the same as the body of confined air. As the velocity of the column of liquid between the chamber L and the pump is accelerated and its pressure increased during the rst part of the stroke, the plunger 38 will be raised, and as the velocity and pressure decreases during the last part of the stroke the plunger will fall. Of course it will be understood that the plunger 38 may be acted on by a spring, instead of being Weighted, or that the chamber L may be a cylinder having a piston which is acted on by either a weight or spring. Since the action of the body of confined air or the weighted or spring-pressed plunger or piston is, in effect, but a yielding weight or connectin interposed between the two parts of the column in the force-main, it is evident that any form of equalizer which will perform this function will secure the desired effect, and will therefore be Within the scope of the invention. In some cases the. equalizer may consist of a simple stand-pipe located at the v point occupied by the chamber L. In vsuch case the liquid will simply rise in the standpipe during the first part ofthe Stroke and fall back to its normal level during the last part of the stroke. When a stand-pipe with an open end is employed, it must of course be somewhat higher than the head against Which the pump is Working. Y,

v The present invention can be appliedto duplex as well as to single pumping-engines. In such case each side of the engine will be provided with an independent force-main extending from the pump to the chamber L, as illustrated in Fig. 5. From the chamber L only a single mainis necessary; or two or more independent pumps may be connected to the chamber L in the same manner as the two sides of the duplex engine.

What I claim is- 1. The combination, with a pump, of the force-main connected thereto without the inf terveutiou of an air-chamber and an equalizer, substantially such as described, located at such a distance from the pump that the column of liquid in the main between the equalizer and the pump will have sufficient inertia to perform the function of a fly-Wheel, and arranged to exert a yielding pressure upon the column in the main,whereby that portion of the column between the equalizer and the pump may move at varying velocities without affecting substantially the veloci ty of the column beyond the equalizer, substantially as described.

2. The combination, with the pump, of the force-main connected thereto without the intervention of an air-chamber and an equalizer consisting of the chamber L, containing a volume of confined air located at such a distance from the pump that the column of liquid in the main between the equalizer and the pump will have sufficient inertia to perform the function of a fly-Wheel, and arranged to eX- ert a yielding pressure upon the column in the main, whereby that portion of the column between-the equalizer and' the pump may move at varying velocities without affecting substantially the velocity of thecolumn beyond the equalizer, substantially as described.

3. The combination, with the cylinder c, having the duet 6, and the piston 35, forming the cataract apparatus, of the cock or valve 7, the chamber 18, havingthe plunger 17, connected to said cock or valve, and the pipe 24, connecting said chamber with the force-main K, substantially as and for the purposes set forth.

4. The cataract apparatus consisting ofthe piston 35 and t-he cylinder c, having the duct 6, and the ducts 8 9, provided with the valves 13 14, substantially as described.

5. The combination, with a direct-actingY pumping -engine and its force-main, of an equalizer, substantially such as described, located at such a distance from the pump that the column of liquid in the main between the equalizer and the pump will have sufficient inertia to perform the function of a fly-wheel, and arranged to exert a yielding pressure upon the column in the main, whereby that portion of the column between theVv equalizer and the pump may move at varying velocities without affecting substantially the velocity of the column beyond the equalizer, and means, substantially such as described, whereby the speed of the engine is regulated by varying the length of the pause of the engine at the end of each stroke, substantially as described.

6. The combination, with a direct-acting pumping-engine and its forecmain, of au equalizer, substantially such as described, located at such a distance from the pump that the column of liquid in the main between the equalizer and the pump-will have sufficient inertia to perform the function of a fly-wheel, and arranged to exert a yielding pressure upon the column in the main, whereby that portion of the column between the equalizer and the pump may move at varying veloci ties without affecting substantially the velocity of the column beyond the equalizer,and means, substantially such as described, whereby the 3o main valve of the engine is moved slowly up to the point where the admission of steam begins and quickly thereafter, substantially as described.

7. The combination, with the pump and its 3 5 force-main, of an equalizer, substantially such as described, located in the force-main and arranged to permit the inertia of the column in the main to aid the engine during the last` part of the stroke, thereby permitting the 4o steam to be used expanslvely, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

A w. A, P. BIoKNnLL.

Witnesses:-

J AMEs A. Hover, Jiis. J KENNEDY.