US1026637A - Method of pumping liquids. - Google Patents

Description

H. M. 8: T. M. CHANGE.

METHOD OF PUMPING LIQUIDS.

APPLIUATION FILED 311.13, 1911.

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COLUMBlA PMNCIGRAPH 110.. WASHINGTON. D. c.

H. M. & T, M. CHANCE.

METHOD OF PUMPING LIQUIDS.

APPLICATION FILED APR. 13, 1911.

1,026,637, Patnted May14.1912.

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aannnuu WITNESSES INYEIJTORS z a a I v W7 W4. 6. 911M. 7 (74...... flm w HENRY M. CHANGE AND THOMAS M. CHANCE, PHILADELPHIA, PENNSYLVANIA.

METHOD OF PUMPING LIQUIDS.

Specification of Letters Patent.

Application filed April 13, 1911.

PatenteolMay 11, 1912. Serial No. 620,804.

To all whom it may concern:

Be it known that we, HENRY M. CHANGE and THOMAS M. CHANCE, citizens of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented new and useful Improvements in Methods of Pumping Liquids, of which the following is a specification.

Our invention relates to those methods of pumping liquids in which an oscillating column or body of liquid is used as an oscillating fly-wheel to transmit and to absorb energy and to give out energy in performing useful work, and may be employed in operating those types of apparatus in which power from an expanding medium such as steam, compressed air or an ignited combustible charge or from other actuating force is transmitted to the liquid by means of a mechanical actuator such as a piston or plunger, and also in operating those types of pumps in which an expanding medium acts directly upon a liquid.

The various forms of mechanism which may be employed for pumping liquids by the use of our method include almost all forms of reciprocating apparatus in common use for pumping liquids. By the term liquid, we mean to include not only simple liquids but also mixtures of liquids and such mixtures of liquids and solids as are capable of being pumped.

When velocity is imparted to a body of liquid, the energy represented by the momentum of said body may be used to assist the pump in completing its full stroke, to create a region of low pressure near the pump into which a new increment of liquid may be drawn, to do work on an accumulator (or in compressing the explosive charge of another pumping unit) thus storing energy to be utilized during the return stroke of said body of liquid, to effect the discharge of liquid, or to perform two or more of these functions; and the momentum of the return stroke of said body of liquid may be used, to efiect the return stroke of a mechanical actuator, to compress a charge of combustible mixture, to create a'region of low pressure into which a new increment of liquid may be drawn, to eflect the dis charge of liquid or to perform two or more of these functions. In performing these functions the effectiveness of the moving body of liquid depends upon its mass and upon its velocity, and the velocity and the time required to impart such velocity will depend upon the differences in pressure by which the oscillations are produced; for if the body of liquid be acted upon by a force producing a given actuating pressure, the pressure available for imparting velocity to the liquid will be the difference between the actuating pressure and the pressure of the accumulator against which the body is thus forced to travel, and the same reasoning applies also to the time and velocity elements of the return stroke. The velocity of the out-stroke can therefore be increased and the time decreased by increasing the actuating pressure or by decreasing the accumulator pressure against which the body of liquid moves, and the velocity of the return-stroke may be increased and the time decreased by increasing the pressure by which it is actuated or by decreasing the pressure against which its travel is effected. But when the actuating pressure is fixed by the type of apparatus or by the character of the source of energy and increased velocity of the out-stroke is attained by reducing the accumulator pressure, such reduction in accumulator pressure will result in a lower volocity for the return-stroke of the body of liquid unless the pressure against which said stroke is made be correspondingly reduced.

In our improved method of pumping we effect such a reduction of pressure by causing the continued travel of the body of liquid after the end of the power stroke to produce and to maintain a void, or space not filled with liquid,a vacuum or partial vacuum,at the rear of the moving body of liquid and against which the body of liquid will travel in making a portion of its return stroke. Having thus created an extremely low pressure at the rear of the body of liquid, it becomes possible to effect the return stroke with a correspondingly low accumulator pressure, and as under certain conditions this pressure may be less than the pressure of the atmosphere it becomes possible to use the atmosphere as an accumulator of infinite size to replace the pressure chambers or other forms of accumulators heretofore used in pumping liquids by means of an oscillating body of liquid. We are thus enabled to employ apparatus in which the oscillating body of liquid is in direct communication with the source of be so constructed as to be air-tight, for it is supply even if this be below the level of the pump chambers and to dispense with suction or intake valves.

The term vacuum or partial vacuum is herein used to mean a void, or space not filled with liquid and occupied by gases or vapors at low tension.

In constructing apparatus suitable for carrying out our method of pumping liquids we do not require mechanisms or devices not now used or known, and we do not limit ourselves to those forms of valves and the mechanism for operating same, nor to those types of internal combustion chambers and actuators which we have used to illustrate the operation of our method of pumping, as it is evident that these may be varied in detail and in number, and that the oscillating body of liquid may be contained in two or more conduits and that any desired form of pressure chambers or accumulators may be used without departing from the spirit of our invention.

In constructing such apparatus advantage may be taken of the fact that the liquid contained in the intake or suction conduit may be used as the oscillating body of liquid, and that this conduit may be horizontal or vertical, curved or straight, and through its mouth or intake the liquid in the supply 01' sump may be maintained in free communication with atmospheric pressure. IVhen so constructed the conduit containing this body of liquid is without valves (excepting possibly stop valves for use when the pump is not in operation) so that the liquid contained therein may be free to move in either direction in response to forces acting upon it from the pump at one end and from the atmosphere at the other end. In operating apparatus of these types the outor powerstroke is assisted by the force of gravity (represented by the weight of liquid in the vertical portion of the column) and the return-stroke is retarded by this force, but the pressure actuating the return-stroke is constant.

It will be understood that our method of pumping may be used with pumps in which the fuel, whether gaseous, liquid or solid, is introduced into the combustion chamber during or subsequent to the compression of air in which the fuel is to be burned, and we therefore use the terms combustible mixture, combustible medium, charge of combustible mixture, etc., to include air or a charge of ,air which may be introduced and compressed prior to the admission of the fuel.

In all forms of apparatus adapt-ed to the operation of our method of pumping, that part of the apparatus adjacent to the region in which the above described void, or space not filled with liquid, is to be created must essential in operating our method that the void or space so created shall be maintained atlow pressure by excluding air or gases from such space, so that said space will contain only aqueous vapor and such gases as are contained in (or occluded by) the oscillating body of liquid.

Our method of pumping may be carried out with internal combustion pumps of those types provided with two chambers, each of which is alternately used as a. combustion chamber, and as an intake and compression chamber, as well as with those types which have only one combustion chamber.

In the drawings Figure I is a vertical central cross-section illustrating how our method of pumping may be used with pumps in which the power is applied by means of a mechanical actuator such as a piston or plunger; Figs. II, IV, V, VI and VII are central vertical cross-sections illustrating how such method may be applied to direct-acting internal combustion pumps having one combustion chamber; Fig. III is a central Vertical cross-section which illustrates how such method may be applied to direct-acting internal combustion pumps having two combustion chambers; Figs. I, II and III illustrate applications of the method when the suction column is used as the oscillating body of liquid; Figs. I and II illustrate the use of air chambers connected to the discharge main; Figs. I, II, III, V, VI, and VII illustrate applications of the method where the source of supply is below the level of the pump chamber, and Fig. IV illustrates an application of the method when the source of supply is above the level of the pump chamber; Figs. V, VI, and VII illustrate applications of the method when the momentum of the moving body of liquid on its out-stroke is used to discharge liquid; Fig. VI illustrates an application of the method when a pressure chamber is used to store energy to be used in effecting the return-stroke of the body of liquid, and Fig. VII illustrates an application of the method when the liquid contained in the pump main is used as a part or portion of the oscillating body of liquid.

In Fig. I, 1 is a piston or plunger which is connected by means of the piston rod 2 with a source of power by which it may be driven forward into the pump chamber 3, which is provided with a packing gland 4, to prevent outward leakage of liquid and inward leakage of air. The chamber 3 is connected with a suction conduit 5 ending in a strainer 6 and immersed in a source of sup ply of liquid to be pumped 7 The suction conduit 5 and pump chamber 3 are connected with the delivery main 8 through the non-return pump delivery valve 9. An air chamber 10 is shown connected with the delivery main 8 to secure uniform flow of liquid through said main, but is not essential to the successful operation of the method. Such air-chambers may or may not be attached to the delivery main, of any type of apparatus using our method of pumping, and are not essential to the successful operation of the method, and this is true also of the strainer 6 as shown connected to the in take or suction conduit of this and other drawings.

In the apparatus of Fig. I which is typical of those in which the energy to be utilized in pumping is communicated to the liquid by a piston or plunger, the cycle of operation is as follows: Upon the commencement of the power stroke the pressure created in the chamber 3 if higher than the pressure against which liquid is to be pumped causes the valve 9 to open and liquid to flow through it into the discharge main 8; at the same time liquid is being propelled through the suction conduit 5 into the source of supply 7 when the pressure in chamber 3 falls below the pressure in the main 8 the valve 9 closes. At the end of the power stroke of the piston or plunger 1 the latter comes to rest against the end of the pump chamber 3 or its further movement is arrestedby the piston-rod 2, and the liquid in the suction conduit 5 continues in motion, creating a void or space not filled by liquid in the upper part of the conduit 5 and chamber 3, the moving body of liquid in the suction conduit 5 being gradually brought to rest by the resistance of the atmospheric pressure acting upon the source of supply 7. The body of liquid in the suction conduit 5 is then driven upward by the pressure of the atmosphere acting upon the source of supply 7, filling the void in the upper part of said conduit and thus atta ins relatively high velocity, and the kinetic energy represented by the momentum of the moving body of liquid forces the plunger or piston 1 back through its return stroke in preparation for the next out or power stroke thereof.

If the return-stroke of the piston or plunger be made by power applied through the piston-rod 2 while the liquid in the suction conduit 5 is moving outwardly, the void or space not filled by liquid in the upper part of the conduit 5 and chamber 3 will be correspondingly increased, and the body of liquid in the conduit 5 in making its return stroke will acquire correspondingly higher velocity and upon filling such void its momentum will produce pressure sufiicient to open the valve 9 so that liquid may flow through said valve into the discharge main 8.

If the pressure produced by the actuator 1 is not suificient to open the valve 9 and discharge liquid during the out-stroke, the

discharge of liquid is effected during the return stroke of the body of liquid as described in the preceding paragraph.

It will be understood that the type of actuator illustrated by Fig. I may be used to apply power to the oscillating body of liquid, when in operating our method of pumping said oscillating body of liquid is used to perform any of the functions illustrated by Figs. II to VII inclusive.

Fig. II shows an apparatus similar to Fig. I except that the mechanical actuator l is replaced by an internal combustion chamber 11, provided with intake valve for combustible mixture 12 and outlet or exhaust valve 13. This combustion chamber is of the two-stroke or two-cycle type, the combustible mixture being introduced through 12 displacing the waste products of combustion through 13, as practised in the operation of internal combustion engines, with or without a scavenging charge of air to precede the admission of the combustible mixture. This chamber is connected with a suction conduit 14 through a valve 16, and through the non-return discharge valve 17 with the conduit 18 and pump main 19. An air chamber 20 is connected to the pump main 19 and the suction conduit 14 is immersed in the supply of liquid 21 to be pumped.

The operation of our method-in an apparatus of this type is as follows: Starting with the ignition of a compressed charge of combustible mixture contained in the upper part of the chamber 11, this chamber and the suction conduit 14 being filled with liquid and the valve 16 being open, the pressure of the ignited mixture is communicated to the liquid in the conduit 14 and opens and causes liquid to flow through the discharge valve 17, and at the same time, and after the closing of the valve 17, imparts velocity to the body of liquid in the conduit 14. When by the expansion of the waste products of combustion pressure in the chamber 11 has fallen to that at which it is desired to exhaust said waste products, the exhaust valve 13 is opened and the valve 16 is closed, cutting oft communication between the chamber 11 and the suction conduit 1%. The momentum of the body of liquid in said conduit causes it to continue in motion, creating a void below the valve 16 and it then comes to rest and makes its returnstroke exactly as described in the apparatus shown by Fig. I. During this period of continued outward travel and of the return stroke of the body of liquid, the waste proclucts of combustion are scavenged from the chamber 11 through the exhaust 13 and a new charge of combustible mixture is introduced into said chamber through intake valve 12. Upon the completion of the re turn-stroke of the body of liquid its momentum produces pressure sufiicient to open the valve 16 and to permit liquid to flow into the chamber 11 and to compress the new charge of explosive mixture contained therein, whereupon the mixture is ignited and the sequence of events repeated.

A simple apparatus for closing the valve 16 is shown by the cylinder 22 with a piston connected by piston-rod 24 to the valve 16, in which one end of the cylinder is connected with the chamber 11, so that when pressure on that side of the piston 23 is less than that on the other side of said piston the movement of the piston 23 closes the valve 16.. To supply pressure to the other end of the cylinder 22, that end may be connected with liquid at the desired pressure or a spring may be inserted in that end of the cylinder. The rapidity of action in closing the valve 16 may be controlled by throttling the discharge of liquid from one end of the cylinder 22. To avoid hydraulic shock the valve 16 should be so closed that the flow of liquid from the chamber 11 into the conduit 14 is not stopped abruptly.

In Fig. III, 25 and 26 are two combustion chambers each provided with the necessary inlet and exhaust valves, and connected by the conduit 27 with a discharge main 28, the suction conduit 29 and the reaction chamber 30. The valve 31, to cut off communication between these chambers and the suction conduit 29 is connected by the valve-rod 32 with suitable means for operating the same. A non-return discharge valve separates the discharge main 28 from the conduit 27.

The operation of this apparatus when pumping by our method is as follows: The upper part of the chamber 25 containing a compressed combustible mixture, the upper part of the reaction chamber 30 containing a compressed cushion of air, the balance of the apparatus being filled with liquid and the valve 31 being open, the charge in 25 is ignited, producing pressure in the conduit 27 and opening and discharging liquid through the discharge valve 33 into the discharge main 28, the pressure in 25 falling by expansion of the waste products permits valve 33 to close, and the charge continuing to expand produces high velocity in the body of liquid in the.suction conduit 29. hen the pressure in chamber 25 falls to the pressure at which it is desired to exhaust the waste products, the exhaust valve to that chamber is opened and the valve 31. is closed, the body of liquid in 29 continues in motion producing a void not filled by liquid in the suction conduit 29, until brought to rest by pressure of the atmosphere acting on the supply 34, and the return stroke of said body of liquid is then effected by said atmospheric pressure acting to force liquid into said void. Dur ing this continued out-stroke and the return stroke of the body of liquid in the suction conduit 29, a charge of combustible mixture has been introduced into the chamber 26 as follows: Upon opening the exhaust valve of chamber 25 the compressed air cushion in the chamber 30 being still above atmospheric pressure causes liquid to be displaced from that chamber and to rise in chamber 25 expelling the waste products of combustion from that chamber and the velocity thus imparted to this liquid and to the liquid in the conduit 27 causes the air in 30 to expand be low atmospheric pressure. When the gases in 25 are expelled the exhaust valve of that chamber is closed by the impact of the liquid or by suitable float controlled mechanism, and the inlet valve to that chamber is held shut and the inlet valve of chamber 26 is released by the same mechanism. Combustible mixture now flows into chamber 26 displacing liquid therefrom and causing it to flow into the reaction chamber 30 in which the pressure is less than atmospheric pressure. Upon the completion of the return stroke of liquid in the conduit 29, the valve 31 opens and the momentum of the moving body of liquid compresses the new combustible mixture in the chamber 26 and the air cushion in chamber 30, the mixture in 26 is ignited and the cycle of events repeated, the next combustible charge being drawn into and compressed in chamber 25, thus restoring conditions to those present when the first charge was ignited. Hydraulic shock may be reduced by closing the exhaust valve before the waste products have been entirely discharged and thus retain a small body of gases in the combustion chamber to act as an elastic cushion, but such body of gases should be very small as compared with the air cushion of the reaction chamber 30.

In operating our method of pumping in using what may be termed two four-stroke cycle chambers to get a two-stroke cycle effect we do not limit ourselves to the type of chambers shown nor to the described also be understood that two four-stroke cycle chambers so operated as to give a two-stroke cycle effect may be used instead of the single combustion chambers shown in Fig. II and in Figs. IV to VII inclusive, when in operating our method of pumping said oscillating body of liquid is used to perform any of the functions illustrated by those drawings.

. In Figs. IV, V, VI and VII a combustion I chamber intended to be operated by the two-stroke cycle method is used to represent a source of power for actuating the oscillating body of liquid. The action of this chamber will be readily understood as identical with that described in connection with Fig. II. The valve between this chamber and the horizontal conduit shown by each of these drawings is closed after the end of the power stroke of the ignited combustible mixture, the continued travel of the body of liquid after the closing of this valve creating a space not filled with liquid adjacent to said valve, all of which will be readily understood from the description of Figs. II and III, and need not be repeated in detail for each of these illustrations.

Fig. IV shows how our method of pump ing may be used when the source of supply 35 is at an elevation higher than the pump chamber, the conduit 36 containing the oscillating body of liquid being partly horizontal and partly vertical; 37 is the discharge valve, 38 the discharge main, 39 the valve closing communication between the chamber 40 and the conduit 36. The continued travel of liquid in conduit 36 after the clos ing of the valve 39, creates a void adjacent to said valve, and the velocity of the return stroke of the body of liquid is increased by the presence of this void or space not filled with liquid. A simple device for operating the valve 39 is shown by connecting it by the piston rod 41 to a piston 42 working in a cylinder 43 which through the connection 45 is in communication with a source of pressure maintained at or'slightly above the pressure at which it is desired to open the exhaust valve, and which through the connection 44 is in communication with the liquid in the chamber 40 or conduit 36, so that when the pressure in the latter falls below the pressure at which it is desired to open the exhaust the piston 42 will by its movement close the valve 39.

In Fig. V 46 is the supply, 47 is the suction conduit, 48 is the suction valve, 49 is the discharge valve, 50 is the discharge main, 51 is the conduit containing the oscillating body of liquid and 52 the valve closing communication between the conduit 51 and the combustion chamber 53. This drawing is designed to illustrate our method of pumping as used with apparatus which utilize the energy represented by the momentum of the moving body of liquid to discharge liquid during the power-stroke and the continued travel thereof through the discharge valve 49, the return stroke being made against and to fill the void created by the continued travel of the out-stroke as in other applications of our method already described, and which will be readily understood from the preceding descriptions.

In Fig. VI the oscillating body of liquid 5 is contained in the conduit 54 and oscillates between an accumulator shown as a pressure chamber 55 and the power chamber 56. In

' of the conduit adjacent to the power chamber 56 and is actuated by the expansion of air in the chamber 55, attaining high velocity and permitting the air in said chamber to expand to less than atmospheric pressure, whereupon the inlet valve 59 opens and a new increment of liquid is drawn in while the momentum of the moving body of liquid is expended in compressing combustible mixture in the chamber 56.

Fig. VII shows an application of our method of pumping with apparatus in which the liquid to be pumped is drawn in at a point adjacent to the void or space not filled with liquid at the rear of the moving body of liquid, through the inlet valve 60, the supply being throttled or controlled by a valve 61 which can be adjusted to any desired position by means of the handwheel 62, but which is always kept in such a position as will prevent the liquid drawn in from filling said void. The drawing also illustrates an application of our method of pumping to apparatus in which the liquid contained in the discharged main 63 is used as the oscillating body of liquid. The details of the operation of our method of pumping in its applications to apparatus of this type will be understood from the preceding descriptions.

It will readily be understood that our method of pumping as herein described may be used in connection with two or more oscillating bodies of liquid operated by two or more combustion chambers or by one or more actuating pistons or plungers, or that the body of liquid may be made to oscillate between two power chambers alternately compressing the charge in each and discharging and taking in liquid at each stroke, the essential feature of our invention being the method by which a void or space not filled with liquid is obtained and maintained at the rear of the oscillating body of liquid by the continued travel of said body of liquid after the actuating force has been cut off, and the use of this void or space to increase the velocity of the return-stroke, and to decrease the pressure necessary to actuate said return stroke.

The apparatus shown in the drawings Figs. I, II, III and IV is of the same type as that shown but not claimed in an application for patent, filed by us in the United States Patent Otfice Nov. 6th, 1910, Serial N 0. 590,790, for a method of pumping liquids in which a portion of the energy of an expanding medium is used to pump liquid against relatively high pressure while the balance of the said energy is stored in an accumulator or used to pump agamst relatively lower pressure, and this apparatus has beenmade the subject of another application for patent filed by us 1n the United States Patent Office January 10th, 1912, Serial No. 670,856, for apparatus for pumping liquids.

Having thus described our lnvention, we claim:

1. A method of pumping liquids, in which an oscillating body of liquid is used to transmit and, to absorb energy and to give out energy in performing useful work and in which the liquid to be pumped is drawn in and is discharged by changes in pressure produced by the application of energy and by the oscillations of said body of l1qu1d, which consists in applying pressure to and impart-ing velocity to said body of liquid, in cutting off from said body of liquid further application of pressure after sald body of liquid has attained movement of relatively high velocity, in permitting said body of liquid to continue in motion, thus creating a space not filled with liquid ad acent to the rear end of said moving body of liquid, in preventing the entrance of air or gases into said space simultaneously with the intake of liquid to be pumped and in causing the return oscillation of said body of liquid to be made toward said space, thereby increasing the velocity of said return oscillation and reducing the pressure necessary to effect said return oscillation and permitting liquid to be pumped to be taken into the apparatus while the said return oscillation is being made.

2. A method of pumping liquids with} internal combustion pumps which consists 1n imparting motion of relatively high velocity to a body of liquid by means of the pressure and expansive force produced by the combustion of a combustible mixture, in cutting off from saidbody of liquid further a plication of said pressure after said body of liquid has attained said high velocity, in permitting said body of liquid to continue in motion, thereby creating a space not filled with liquid adjacent to the rear end of said moving body of liquid, in preventing the entrance of air or gases into said space, in causing the momentum of said moving body of liquid to be expended against the pressure of an accumulator, in causing the return stroke of said body of liquid to be actuated by the pressure of said accumulator and to be made toward said space not filled with liquid, in causing the energy represented by the momentum of said body of liquid acquired during said return stroke to compress a new charge of the combustible mixture in preparation for the combustion thereof and in causing the liquid to be pumped to be drawn in and to be discharged by the variations in pressure thus produced in said oscillating body of liquid.

In testimony whereof, we have hereunto signed our names at Philadelphia, Pennsylvania, this twelfth day of April 1911.

HENRY M. CHANCE. THOMAS M. CHANCE. Witnesses:

GHAs. BUsH, E. M. LEAOH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.

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