US1766852A - Pump - Google Patents

Description

'June 24, 1930. u TODD 1,766,852

7 PUMP Filed Oct. 15, 1928 s Sheets-Sheet 1 INVENTOR June 24, 1930 u. G. TODD 1,766,852

PUMP

Filed 001;. 15, 1928 5 Sheets-Sheet 2 INVENTOR k v 2 W 3 a gw fi's ATTORN Patented June 24, 1930 UNITED STATES PATENT orrics ULrsnss G. TODD, or ROCHESTER, NEW YORK, ASSIGNOR r T nn VPFAUDLER 00., or noonnsrnn, NEW YORK,'A coRronA'rIon on NEW YORK PUMP This invention relates to pumping apparatus, and especially to apparatus for use in extracting fluid from a partially evacuated vessel. The principal object of the invention is to provide a satisfactory pump which will operate at comparatively high efliciency in drawing fluid from a partial vacuum. v 7

Another object of the invention is the provisionof an improved hook-up arrangement or piping system for a pump to facilitate the operation of the pump in withdrawing fluid from a partial vacuum. 7

Still another object .is the provision of a '15 pump having one or more supplementary ports to facilitate the flow of fluid into the pump. Another object is the provision of a pump in combination with means for reducing the pressure within the pump in 2 order to aid the flow of fluidinto the pump from a partial vacuum.

A further objectof the invention is the provision of a comparatively flexible pump hook-up so that a pump for withdrawing fluid from a vessel may be operated in' different ways at different times in accordance with varying conditions. r v

To these and other ends the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification. a

In the drawings: V

Fig. 1 is an elevation of an apparatus constructed in accordance ,with one possible embodiment of the invention; 7

Fig. 2 is a vertical section showing details of the pump illustrated in Fig. 1;

Fig. 3 is a similar vertical section illustrating details of a pump having a slightly different form of valve mechanism;

Fig. 4 is an elevation with parts in section showing another possible embodiment of the invention; and

Fig. 5 is a vertical section showing details of a pump which may be used in the apparatus shown in Fig. 4.

Similar reference numerals throughout the several views indicate the same parts.

This application, so far as the structure illustratedin Figs. land 2 is concerned, is a division of my copending application, .Se rial No. 148,719, filed November 16, 1926; and in so far as the structure illustrated in Figs. at and 5 is concerned, it is a continuation in part of my copending application,

Serial No. 288,87 9, filed June 8,1928,

This invention relates especially to the withdrawal of fluid from partially evacuated vessels such, for example, as vacuum pans, although (it is not limited to such use. In Fig.1 there is illustrated by way of example a vessel or vacuum pan 10 which may be used for carrying out any desired treatment or process, the contents of the vessel being heated by coils 'orheating elements which may be placed, for instance, ithin a jacket 11 extending around the lower part of the vessel. A partial vacuum may be produced in the vessel by any suitable means such as the eductor 12, an operating-liquid such as water being supplied to the eductor through the pipe 13. The [flow of liquid through the eductor creates a suction in the pipe 14: which connects the eductor to the vessel 10, and the water togetherwith the vapor or air withdrawn from the vesselare discharged through the conduit 15. i I

- -Heretofore ithas usually been necessary or desirable to break the vacuum within the Various'attempts have been made to-extract liquid from such vessels while the process was going on and without breaking the vacuum in the receptacle, but these attempts have either resulted in failure or have been accomplishedjonly with low efficiency in a wasteful and uneconomical manner.

According to the present invention, how- .ever,.means is provided for extracting. liquid from a partially evacuated vessel-in an efii cient and economical manner without breaking or impairing in any waythe degree of vacuum within the vessel, and without interfering with the carryingon ofa'continuous Process or treatment within thevessel if desired. This extracting means may comprise, for instance, a pump and suitable piping connecting this pump to the vessel 10, as shown in Fig. 1.

The details of the pump itself are best shown in Fig. 2, from which it will be seen that there is provided a pump chamber having a portion 20 in which a piston or plunger 21 is arranged to reciprocate, the chamber having anenlargement 22 at one end and 23 at the other end. Substantially centrally of the pump chamber, or at any other suitable point desired, there is an inlet port 24 connected by conduit 25 to the vessel 10 at a point below the liquid level therein, so that the liquid tends to-run down through the conduit 25 to the inlet port 24 of the pump.

Outlet ports 26 are provided adjacent each end of the pump chamber, each of these ports being provided with a valve 27, and conduits 28 convey the discharged liquid to the conduit 29, through which it may be conveyed to any desired point.

- Supplementary ports 32 and 33 are provided leading through the wall of the liquid chamber of the pump and are connected by conduits 34 and 35, respectively, to the vessel 10 at a point above the liquid level therein, as is shown in Fig. 1. These conduits 34 and 35 may be provided with valvemeans for opening and closing them, at proper times.

One suitable form of valve means comprises valve' plugs 36 and 37 secured to a valve rod 38, and moved back and forth within a tube or valve guide 39 by move ments imparted to'the rod 38. This valve rod 38 may be moved, for example, by a bracket 40connected to the valve rod and mounted on the piston rod 41 which operates the piston 2 The piston rod 41 may be reciprocated in any suitable manner, such as by being connected to a piston within a steam cylinder 42 (Fig. 1). The piston rod and connected parts are shown in Fig. 2 at the center of the stroke, and it will be understood that the parts reciprocate in each direction from this central position shown.

In operation, the vessel 10 may contain any liquid which is undergoing any desired process or treatment, and a partial vacuum of, say, 28 inches of mercury may be maintained within this vessel by operation of the eductor 12. When it is desired to withdraw part or all of the liquid from the vessel 10, thismay be done without breaking or'even lowering the vacuum in the vessel by operating the pump.

Assuming that the first stroke of the pisten 21 is to the right from the central position shown in Fig. 2, this movement uncovers the inlet port 24. If there were no vacuum within the vessel 10, liquid would then flow down through the conduit 25 and theport 24 into the pump chamber. On account of the vacuum, however, this flow either does not take place at all or is greatly impeded, unless means is provided for lowering the pressure within the pump chamber. Such means in the present instance comprises the supplementary ports 32 and 33, and the conduits 34 and 35. connected to them.

As the piston 21 moves rightwardly, the valve rod 38 will also be moved rightwardly, and the valve 36 will open the conduit 34 leading to the port 32 although the conduit 35 will be kept closed by the valve 37. When the valve 36 opens, the portion of the pump chamber to the left of the piston is then in communication with the upper portion of the vessel 10 above the liquid level in this vessel. A vacuum is thus created in the pump chamber substantially equal to the vacuum in the vessel 10, and this permits the liquid to run freely into thepump'chamber through the port 24.

As the piston 21 moves leftwardly after completing its stroke to the right, the valve 36 closes the conduit 34 at approximately the same time that the left handedge of the piston 21 reaches the left hand edge of the port 24 and thus closes the port. Continued leftward movement of the pistoncompresses the fluid in the left end of the pump chamber and forces it through theoutlet port 26. At the'sa-me time, the valve 37 opens, so that the right hand end of the pump chamber is in communication with the upper portion of the vessel 10 through the conduit This evacuatesf the right hand end of the pump chamber to a degree corresponding substantially to the vacuum within the ves sel 10, and permits the, liquid from the bottom of this vessel to flow readily through the port 24 intothe right hand end of the pump chamber.

As the piston again moves rightwardly after completing its leftward stroke, the liquid which has flowed into the right hand end of the pump chamber is forced out through the right hand outlet port 26, and another supply'of liquid flows into the left end of'the chamber. This pumping action is repeated as long as desired.

As the conduits 34 and 35 leading to the supplementary ports 32 and 33 are connected to the vessel 10 at a point above the liquid level therein,'it may be said that they are connected to a source of vacuum, since this upper portion of the vessel 10 is in turn connected to a source of vacuum such as the eductor 12. It may also be said that the supplementary ports 32 and 33 are connected by the conduits'34 and 35 to a region of sub-atmospheric pressure, since the upper portion of the vessel 10, above the liquid level therein, constitutes such a region.

which have passageways or openings 46 and 47 respectively, extending therethrough.

treme right hand end of their stroke.

The valve rod 38 in the pump shown in .Fig. 3, instead of being attached securely to the bracket to move therewith, extends slidably through an opening in this bracket and is provided with collars 48 and 4.9, as shown, which act to move the valve rod only after the bracket tOhas traveled a predetermined distance of lost motion.

The operation of the pump shown in Fig. 3 is substantially similar to that of the pump previously described. In Fig. 3, thepiston and associated. parts are shown at the eiIrt will be observed that the passageway 46 in the valve 36 isin alinement with the conduit 34 so-that the port 32 is in communication with the upper portion of the vessel 10, thus creating a corresponding vacuum in the left hand endozE the pump chamber, and assisting the flow of liquid thereinto through the port 24. 1

As the piston 21 moves leftwardly from its extreme righthand position, the valve 1'' rod 38 does not move at first, but about the time that the piston 21 closes the port24: the bracket 40 comes into contact with the collar 48 on the valve rod 38, and moves this rod leftwardly, shifting the valve 36" to close the conduit 34. Thevalve 37' keeps the conduit 35 closed, however, untilnear the end of the leftward stroke, when the passageway 37 Y is finally brought into alinementwith the conduit 35 toestablish communication between the port 33 and the upper part of the vessel 10. Then the piston againmoves rightwardly, from the left end of its stroke, the valve 37' remains open until about the center of the stroke and the valve 36': isopened practically at the :end

" of the stroke. NVhen the valves are opened source of vacuum, the flow of liquid irom' to establish communication betweenthe supplementary ports 32 and 33, and the the evacuated vessel into the pump is l-as sisted in a manner similartothat which has: been previously described. A 1 Referring now to Figs. i-and 5, there is shown a pump and connections which are similar in many respects to those prev ously described, but which differ in some features fromthe constructions shown in Figs. lto

3. In the Fig. l construction, a vessel jinay be employed for carrying on any desired process 'or treatment, the material The portion 71 of which the piston reciprocates has an inlet within this vessel being heated if desired by any suitable heating means (not shown). The upper portion of the vessel'60 may be connected by a conduit 61 to any suitable source of vacuum such as the eductor 62, which may be'operated by water or other liquid supplied to. it through a pipe .63 and 1 discharged throughthe conduit 64. A valve 65 may be provided in .the conduit 61.

A pump having a piston 70 mounted for reciprocation within a cylindrical portion 71 of a pumpchamber having enlargements opening which may be similar, for ex ample, to the inlet port 24 in the pump of the form shownin Fig. 2. This pump in Fig. 5 has no supplementary ports corresponding to the ports 32 and 33 of the Fig. '2 construction, however. A conduit 81 leads upwardlyfrom the. inlet port 80, and a short distance above the pump it is provided with a T-shaped fitting 82 so that a branch 83 may lead to one side and may be connected to the bottom of the vessel 60, as

is plainly shown in Fig. 4. A check valve; 84 may be used if desired in this conduit83 to prevent liquid from being forced back into the-vessel 60 during the operation of the.

"apparatus. V I

Above the T-shapedfitting 82 the-conduit 81 continues upwardly and may be provided if desired with an enlarged portion 'or stand-pipe 85 which is connected at its top to a conduit 86 having a 'T-shaped fitting 87 secured thereto; A float valve of any suit-1 able-construction, indicated diagrammatically' at 88, may be placed at any suitable point such as the .top of the stand-pipe portion 85, so that this conduit will be closed or shut off ifnthe liquid level within it; should everrise as high as this valve.

A conduit 89 may lead in one direction from the 'T 87 past a valve 90 to any su table evacuating means such as an eductor indicated diagrammatically at 91, which educton,

maybe operated by liquid supplied to it through the conduit 92 and discharged from the conduit 93. A conduit 95 leads from the T 87 in a direction opposite to the conduit 89, and is connected to the upper part of the vessel 60, a valve 95 being prov-ided in this conduit. v

The apparatus illustrated in Figs. 4 and 5 may be operated in a number of ways, one

of which will now be described. Assuming that the vessel contains liquid to some elevation such as that indicated by the line 100 in Fig. at, a partial vacuum maybe applied to this vessel by operating the eductor 62, the valve being open. Any desired treatment of the liquid within the vessel 60 may be commenced either before or after the vacuum is applied to the vessel 60, and this treatment may be continued as long as desired. The present arrangement of the pump and conduits allows liquid to be withdrawn fromthe vessel 60 at any time without breaking the vacuum and without interfering in any way with whatever process or treatment is being carried on.

lVlien it is desired to withdrawa part or all of the liquid,- the eductor 91 may be set in operation, the valve '90 being open and the valve 95 being closed. Preferably the eductor 91 or other source of vacuum to which the conduit 89 is connected is-of such a character that it may produce a vacuum of a slightly higher degree than that existing within the vessed' 60. Best results are usually obtained when'the degree of vacuum within the stand-pipe 85 is slightly higher than that within the'vessel 60, but satisfactory operation is produced when the two vacuums are substantially equal. The connection of the pump chamber through the conduits 81' and 85 to this source .of vacuum 91 will provide an easy outlet for any pressure within the pump chamber and will thus assist the liquid within the vessel 60 to'flow down into the chamber easily notwithstanding the vacuum in this vessel.

' If the vacuum produced by the source 91 is greater than that within the vessel 60,

liquid will rise within the conduit. 85 to a point somewhat above the liquid level 100 in the vessel 60, the level never rising above "the'float valve 88, however, since liquid at this elevation would close the valve and operativelydisconnect the eductor 91 from the conduit hen the eductor 91 1s inoperation, liquid from the vessel 60 is drawn through the conduit 83 to the T 82, and no ditliculty is experienced in getting the liquid to flow into the pump chamber although such flow would be considerably obstructed and lessened if an arrangement of this kind were not provided. 7

As fast as the pump piston reciprocates,

'the liquid which has flowed into the pump chamber is forced out through the discharge ports, and other liquid flows in to take its lace. Q i

The conduit connection 94; allows a single eductor to be used in place of two eductors,

when desired. For instance, the valve 90 may be closed and the valve 95 opened, the eductor 62 being continued. in operation and eductor 91 being shut down. The conduit or stand-pipe 85 would then carry a vacuum equal to that within the vessel 60, and the liquid from the vessel would still flow freely to the T connection 82, from which it would pass easily into the pump.

On the other hand, if it should be necessary or desirable to shut down the eductor 62, the valve 65 may be closed and the valves 90 and 95 may both be opened, the eductor 91 being placed in operation. In this case, the stand-pipe 85 would be evacuated by the eductor 91 andthe vessel 60 would also be evacuated by this same eductor. If desired, a somewhat higher vacuum may be maintained in the stand-pipe 85 than that in the vessel 60 by closingthe'valve 95 partially.

Thus it is seen that the apparatus illustrated in Fig. 4 is of flexible character and may be used in various ways. At times both of the eductors 62 and 91 may be used together, but at other times either one of the eductors alone could be used to operate the apparatus satisfactorily.

It should be understood that hydraulically operated eductors such as are shown in the drawings are disclosed merely by way of example, and any suitable vacuum pump or othersource of vacuum may be substituted for one or all of the eductors shown.

According to this invention above disclosed, liquid may be satisfactorily withdrawn from a vessel evacuated practicallyto any obtainable degree, vacuums of 28 inches or more having been used in practice.

-\Vhile certain embodiments of the invention have been disclosed, it is to be understood that the inventive idea may be carried out in a number of ways. This application is therefore not to be limited to the precise details shown, but is intended to cover all variations and modifications thereof fallum to said vessel to produce a partial vacuum therein, a pump for extracting liquid from said vessel when the latter is partially evacuated, conduit means connecting said pump to said vessel below the liquid level therein, a second source of vacuum, and conduit means connecting said pump to said second source of vacuum toassist the flow of liquid into said pump from said evacuated vessel.

. 2. The combination with a vessel containing liquid, of asource of vacuum, conduit means connecting said source of vacuum to said vessel toproduce a partial vacuum therein, a pump for extracting liquid from said vessel when the latter is partiallyevacuated,'conduit means connecting said pump to said vessel below the liquid level therein, a second source of'vacuum, and conduit means connecting said pump at will to either of said sources of vacuum to assist the flow of liquid into the pump from said evacuated vessel.

3. The combination with a vessel containing liquid, of two sources of vacuum, conduit means connecting said vessel at will to either of said sources of vacuum to produce a partial vacuum in said vessel, a pump for extracting liquid from said vessel when the latter is partially evacuated, conduit means connecting said vessel to said pump to supply liquid thereto, and conduit means connecting said pump to one of said sources of vacuum to assist the flow of liquid into said pump.

4. The combination with a vessel containing liquid, of a pump for extracting liquid from said vessel when the latter is partially evacuated, conduit means connecting said vessel to said pump to supply liquid thereto, and means for creating a partial vacuum in said vessel and for subjecting a portion of said pump to vacuum of a higher degree 7 than the degree of vacuum within said vessel, to assist the fiow of liquid from said vessel into said pump.

5. The combination with a vessel containing liquid, of a source of vacuum, conduit means connecting said source of vacuum to said vessel to produce a partial vacuum therein, a pump for extracting liquid from said vessel when the latter is partially evacuated, said pump having an inlet port, an outlet port and a supplementary port, conduit means connecting said vessel to said inlet port to supply liquid thereto, a second source of vacuum, and conduit means connecting said supplementary port to said second source of vacuum to assist the flow of liquid into said pump.

6. The combination with a vessel containing liquid, of a source of vacuum, conduit means connecting said source of vacuum to said vessel to produce a partial vacuum therein, a pump for extracting liquid from said vessel when the latter is partially evacuated, said pump having an inlet port, an outlet port, and a supplementary port, conduit means connecting said vessel to said inlet port to supply liquid thereto, a second source of vacuum, and conduit means connecting said supplementary port at will to either of said sources of vacuum to assist the flow of liquid into said pump.

7. The combination with a vessel containing liquid, of two sources of vacuum, conduit means connecting said vessel at will to either of said sources of vacuum to produce a partial vacuum in said vessel, a pump for extracting liquid from said vessel when the latter is partially evacuated, said pump having an inlet port, an outlet port, and a supplementary .port, conduit means connecting said vessel to said inlet port to supply liquid thereto, and conduit means connecting said supplementary port to one of said sources of vaccum to assist the flow of liquid into said pump.

8. The combination with a vessel containing liquid, of a pump for extracting liquid from said vessel when the latter is partially evacuated, said pump having an inlet port, and outlet port, and a supplementary port, conduit means connecting said vessel to said inlet port to supply liquid thereto, and means for creating a partial vacuum in said vessel and for subjecting said supplementary port to vacuum of a higher degree than the degree of vacuum within said vessel, to assist the flow of liquid from said vessel into said pump.

' ULYSESS G. TODD.

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