US3737255A

US3737255A - Vertical sump pump

Info

Publication number: US3737255A
Application number: US00218348A
Authority: US
Inventors: G Emeny
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-01-17
Filing date: 1972-01-17
Publication date: 1973-06-05
Anticipated expiration: 1990-06-05
Also published as: CA974402A

Abstract

Vertical sump pump for deep pits having a pumping chamber and impeller positioned below the desired upper liquid level and an extension conduit extending down from the pumping chamber and terminating below the lower liquid level.

Description

United States Patent 1191 Emeny 1451 June 5, 1973 [54] VERTICAL SUMP PUMP 2,626,086 1 1953 Forrest ..417 424 3024 730 3/1962 Towle [76] Inventor. George B. Emeny, 575 H1ghland Avenue, Salem, Ohio 44460 3,163,117 12/1964 l-laent ens ..4l7/424 [22] Filed; Jam 17, 1972 FOREIGN PATENTS OR APPLICATIONS [211 App], 218,343 1,062,349 12 1953 France ..417 424 Primary Examiner-C. J. Husar [52] US. Cl ..417/424 51 1111.01 ..F04b 17 00 A'wmey wln'am Webb Davd Hans [58] Fleld of Search ..4l7/424; 415/88 [57] ABSTRACT [56] References Cited Vertical sump pump for deep pits having a pumping chamber and impeller positioned below the desired UNITED STATES PATENTS upper liquid level and an extension conduit extending 2,504,140 4/1950 Mill ..4l7/424 down from the pumping chamber and terminating 3,519,365 7 1970 Conhagen ..415/88 below the lower liquid level. 2,515,538 7/1950 Walls; 417/424 2,625,110 1/1953 Haentjens et a1 417/424 10 Claims, 6 Drawing Figures 335 I 13 L22 \LI2 L13 .ing downwardly from the floor level. The sumps are substantially emptied to their lower liquid level and allowed to fill to an upper liquid level before the pump is actuated to empty the sump again. To maintain the pumps prime, an impeller and centrifugal pumping chamber (pump casing) are often maintained below the lowest controlled liquid level in the sump.

In many instances it is very unwieldy to construct and install a vertical pump having its impellers submerged below the lowest liquid level. For example, the pit or sump may be so deep that to submerge the impeller below the lowest liquid level would require an excessively long mechanical guide and support structure for the impeller drive shaft. The cost of this design may be prohibitive, and installation and maintenance very difficult. On the other hand, an overhung shaft driving the impeller as described in my U.S. Pat. No. 2,934,245 may become mechanically unstable after a certain length is reached depending upon the structure at the rotating element.

Since many pits and sumps are located in buildings where there is only a limited amount of head space above the floor level, it is extremely desirable that the pumps be capable of installation by means of easy elemental assembly on the site.

It is an advantage of this invention to provide such a pump for relatively deep pits and sumps having an overhung impeller shaft with the impeller positioned just below the upper liquid level and having a suction pipe extending downwardly therefrom and terminating below the lower liquid level. This suction pipe allows the liquid from below the level of the suction pipe intake to flow to the impeller during its pumping cycle and to maintain the prime and pumping action of the pump until the liquid is lowered to its controlled lower level in the sump or until suction is lost when the liquid level approaches close to the suction pipe inlet.

It is a further advantage of this invention to provide a pump which greatly reduces maintenance costs. It is yet another advantage that the overhung shaft and impeller assembly and the suction tube assembly may be withdrawn from the pump support structure without disturbing the discharge pipe or other elements below the top support plate or flange. It is yet another advantage that the support structure may be easily fabricated from flat plate and standard pipe eliminating the need for costly castings using few, if any, gaskets.

It is another advantage that the upper part of a float or other mechanical, electrical or pneumatic control guide or protecting tube is a part of the pump structure and the lower extension of such guide tube may be removably installed with the pump structure in place.

Briefly, according to this invention, the pump comprises the pump support structure positioned within the sump and having a centrifugal pumping chamber just below the upper liquid level. The pump further comprises rotating elements including the motor, overhung shaft and impeller which are releasably attached to the pump support structure in such a way that the impeller is easily removably positioned within the centrifugal pumping chamber. The pump comprises a suction pipe extending from the centrifugal pumping chamber to just below the lower liquid level. The suction pipe may take several forms as described in the following detailed description.

This invention is not confined to single stage centrifugal pumping. It may apply to single or multistage pumping units of the centrifugal, axial flow, regenerative turbine or positive displacement rotary types.

Further features and other objects and advantages of this invention will become apparent from a careful reading of the following detailed description with reference to the drawings in which:

FIG. 1 is a section view of a pump according to this invention;

FIG. 2 is an elevation view of the pump shown in FIG.

FIG. 3 is a section view taken along line A-A of FIG. 2;

FIG. 4 is a section view taken through line 8-8 of FIG. 2;

FIG. 5 is a partial section of an embodiment of this invention having a pump shaft extension extending down into the suction tube; and,

FIG. 6 is a partial section of an embodiment of this invention wherein the suction tube comprises an integral part of the impeller and rotates therewith.

Referring to FIGS. 1 and 2, the pump support structure 1 is comprised of a top flange 2, a pump casing 3 and standards 4, spacing the pump casing below the top ing flanges at each end. In this way, one or more standards may also serve as a discharge tube 30 or tubes and another may serve as a guide 32 for float control or other pump control parts. The standards may be spaced substantially or apart about the pump shaft 6 as shown in FIG. 4. If only two standards are used, the spacing should be about 180 apart, though four or more standards may be used also. In any case, the standards may have dual functions.

The top flange 2 is arranged to cover at least a portion of the pit from which the liquid is to be removed and has at least one opening 5 therein for passage of the rotary elements of the pump including the shaft 6 and the impeller 7 and column 45. The top flange may also have openings through which the discharge tube 30 and the guide tube 32 pass or open. The top flange is arranged to support the pump casing within the pit. The length of the standards are such that the pump casing is somewhat below the top liquid level.

The pump casing is preferably comprised of an upper end plate 11 and a lower end plate 12 parallel thereto. The periphery of the pump chamber preferably comprises one or more curved strips 13 shaped to form one or more of volutes having openings 14 (see FIG. 3) therein for the discharge of liquid thrown thereagainst by the rotating action of the impeller 7. One possible shape of the strips 13 is shown'in FIG. 3.

The upper end plate 11 has an opening 15 for the passage of the impeller but which is of a smaller diameter than the opening 5 in the top flange. The lower end plate has an opening 16, which is smaller than opening 15. Preferably, the

openings

5, 15 and 16 are circular and coaxial. A suction tube (extension conduit) 20 passes through the opening 16 in the lower end plate. According to one embodiment of this invention, the suction tube 20 has a flange 21 having a diameter greater than the diameter of the opening 16 in the lower end plate but less than the opening 15 in the upper end plate. In this way, it can be removed from the sump after the rotating parts have been removed.

Preferably, the suction tubeshas a strap 22 which is fastened across the center of the upper opening of the suction tube to act as a means for removing the suction pipe by providing an element onwhich a hook maygrasp. The strap 22 also reduces prerotation of the liquid entering the suction side of the impeller which, if not checked, would reduce the pumping capacity of the impeller.

Where the openings in the top flange 2, upper end plate 11, lower end-plate 12 and the suction tube flange 21 and suction tube 20 are substantially circular, their diameters decrease in the following order: diameter D of opening 5 of the top flange, diameter D of opening 15 in the upper end plate, diameter D of flange 21 on the suction tube, diameter D of opening 16 in the lower end plate and diameter D of suction tube 20.

Preferably, the flange D on the suction tube has a diameter D slightly larger than the maximum diameter of the impeller but smaller than diameter D Preferably, the hole 16 in the lower end plate for the suction tube has a diameter D about halfway between the diameter D of the suction tube flange and the diameter D of the suction pipe 20. In other words, D D (D D 2. In this way, the upward thrust force against the bottom base of the flange 21 does not exceed the weight of the suction pipe. Otherwise, this pipe might become unstable and interfere with the rotating impeller 7 for which its flange may serve as a wearface. Liquid under pressure tends to leak between the lower end plate. 12 and the flange in the suction tube 21 and exert an upward thrust on all of the area of the suction flange that is projected upon the bottom plate. To overcome this problem, it is desirable to have diameter D of the hole in the lower end plate substantially larger than the diameter D of the suction pipe or tube 20. A sufficiently air tight seal is maintained by liquid flowing from the pumping chamber between the flange of the suction pipe and the bottom of the pumping chamber to maintain suction without the requirement of gasketing and bolting them together.

If liquid turbulence in the sump is sufficient, it may cause the suction pipe to sway. Hence, according to a preferred embodiment of this invention, one or more buttons 24 are fastened to the bottom of the lower end plate 12 so that matching latches 55 fastened to the suction pipe will engage the corresponding buttons in a wedging action as the suction pipe is twisted in place on its axis. 2

According to a preferred embodiment of this invention, support tube 32 can also comprise a guide tube for float control parts. So that the whole structure need be no longer than necessary, a float guide extension tube 33 may be removably depended from the support tube 32 by having a stop fastened to its outside diameter such that it will not pass the upper or lower end plate beyond that point because the hole in the upper or lower end plate is smaller in diameter than the inside of the guide tube 32 but larger than the outside of the extension tube 33. This tube extension may be removed by using a hook to engage a hole 34 provided close to the top of the tube.

The rotary elements may be arranged substantially as described in my US. Pat. No. 2,934,245. Hence, releasably mounted above the top flange 2 is a bearing housing assembly 40 having thrust bearings 41 therein for rotatably supporting the overhung shaft 6. As shown in FIG. 1, two bearings in the bearing housing assembly take care of all the thrust and radial loading on the shaft so that no bearings are needed below the top plate. A motor 43 is mounted above the bearing housing assembly 40 and connected to the shaft by a conventional coupler.

Preferably, a protective tube 45 surrounds the shaft 6 and is fixed at its upper end to the lower side of the bearing housing assembly 40. At the bottom end of the protective tube 45 may be a cover 46 for the centrifugal pumping chamber comprising a flange about the end of the protective tube 45. Preferably, guides 47 are mounted on the top of the upper end plate to direct the cover 46 into the correct position over the pump casing. To the bottom of cover 46 may bebolted a flange 49 of a size to be inserted with reasonable clearance into hole 15. By gasketing between cover 46 and flange 49, it is possible to reduce the clearance between the top of the impeller and the pumping chamber upper surface as well as to furnish a wearing plate for the top side of the impeller.

According to a preferred embodiment, the protective tube 45 has a plurality of spaced openings 48 therein. These openings allow the fluid being pumped to flow up into the space between the shaft 6 and the protection tube 45. The fluid then flows out of the openings 48 in the protection tube. The continuous fluid flow seals the top of the pumping chamber preventing air from entering the impeller.

According to another embodiment of this invention as shown in FIG. 5, an extension shaft 50 is mounted on the main shaft 6 below the impeller 7. At the bottom of the extension shaft 50 an axial'or radial flow impeller 51 is mounted within the extension tube 20. Preferably, the axial or radial flow impeller is positioned below the lower liquid level. This impeller aids in maintaining the pump prime during use of the extension tube 2.0, providing in the case of the radial flow impeller there is an opening in the suction pipe just below the impeller that is somewhat smaller in diameter than that of the impeller.

In yet another embodiment as shown in FIG. 6, the suction shaft 20' is fixed to the bottom of the impeller 7 and has at the base thereof vanes 60 which aid in maintaining the pump prime, providing likewise, the opening at the bottom of the suction tube is smaller than that of the inside of the pipe itself.

In this pump the impeller shaft 6 and impeller 7 may be adjustably centered with respect to the column 45 and the hole in its bottom flange 46 by means of a spherical or conical convex surface on the bottom flange of bearing frame 40 resting upon a like but concave surface on the rotating assembly support flange 42. When the centered position is attained, it is maintained by the compression of the two spherical or conical surfaces by a retaining flange 43.

The flanging of the discharge tube ortubes 30 which connect to the stationary piping system may be composed of two slip flanges arranged to fit snugly onto the outside diameter of each discharge tube. The top flange 36 may be material of the same type as the discharge tube to resist corrosive action. The back-up flange 37 is machined to contain a sealing ring 38 which when compressed against the bottom face of upper flange 36 also squeezes against the outside of discharge tube 30 and thereby prevents leakage. This permits some axial location adjustment, 360 radial adjustment and some face angle adjustment to more easily adapt to and mate with companion flanging in the stationary piping system to which the discharge tube is to beconnected.

Preferably the shaft 6 is comprised of two parts. The upper part of the shaft, that is, the part generally above plate 2 and secured in the bearings is solid. The lower portion of the shaft is tubular. The connection between the upper solid and lower tubular portions of the shaft 6 is by bolting or other means providing for easy releasability. This impeller shaft structure provides greater mechanical stability to the lower portion of the shaft. Further it enables a wider choice of anti-corrosive materials for use as the lower shaft.

Having thus described my invention with the detail and particularity as required by the Patent Laws, what is desired to be protected by Letters Patent is set forth in the following claims.

I claim:

1. A pump for removing liquid from a pit having upper and lower liquid levels comprising:

a top flange for covering at least a portion of the pit;

a casing defining a pumping chamber for being disposed below the upper liquid level and above the lower liquid level;

standards depending from the top flange to support,

the pumping chamber;

an overhung impeller shaft extending downwardly through the top flange and an impeller attached thereto positioned within the pumping chamber; a motor mounted above the top flange for turning the impeller shaft and impeller;

an extension conduit extending downwardly from the pumping chamber for terminating below the lower liquid level; and,

an extension shaft pendent from the impeller and and auxiliary impeller within the extension conduit supported by the extension shaft.

2. A pump for removing liquid from a pit having upper and lower liquid levels comprising:

a top flange for covering at least a portion of the pit; a pumping chamber for being disposed below the upper liquid level and above the lower liquid level comprising a casing defining a pumping chamber; standards depending from the top flange to support the pumping chamber;

an overhung impeller shaft extending downwardly through an opening in the top flange and an impeller attached to said shaft and positioned within the pumping chamber;

a motor mounted above the top flange for turning the impeller shaft and impeller; a protection column positioned about the impeller shaft and having a flange about the lower end for covering an opening over the top of the pumping chamber; and,

an extension conduit extending downwardly from the pumping chamber through an opening in the bottom thereof for terminating below the lower liquid level comprising a pipe having a flange at the upper end, the diameters of the openings and flanges decreasing in the following order: opening in top flange, flange at bottom of column or protective tube, opening over top of pumping chamber, flange on top of extension conduit and opening on bottom of pumping chamber, whereby the impeller, impeller shaft and protection column may be removed without disturbing the standards and pumping chamber and thereafter the extension conduit may also be removed.

3. A pump according to claim 2 wherein a second plate is secured to the bottom of the flange at the bottom of the protection column, said second flange shaped to fit into the opening in the top of the upper end plate.

4. A pump according to claim 2 wherein the diameter of the top opening in the pumping chamber is slightly greater than the maximum diameter of the impeller to be used in the chamber, and the diameter of the bottom opening is smaller than the maximum impeller diameter but greater than the outside diameter of the largest extension conduit which may be used.

5. A pump according to claim 2 wherein at least one standard compriss a discharge tube.

6. A pump according to claim 2 wherein at least one standard comprises a housing for a liquid level control mechanism.

7. A pump according to claim 6 wherein aremovable extension tube depends from the standard comprising the housing, said extension tube terminating below the lower liquid level.

8. A pump according to claim 2 wherein the impeller shaft (6) and impeller (7) may be adjustably centered with respect to the column (45) and the hole in its bottom flange (46) by means of a convex surface on the bottom flange of bearing frame (40) resting upon a like but concave surface on the rotating assembly support flange 42.

9. A pump according to claim 2 wherein the flanging of the discharge tube or tubes (30) which may be connected to the stationary piping system is composed of two slip flanges snugly fit onto the outside diameter of the discharge tube, said back-up flange (37) having a sealing ring (38) in a groove thereon such that compression against the bottom face of upper flange (36) squeezes the ring also against the outside of discharge tube (30) and thereby prevents leakage.

10. A pump according to claim 2 wherein the impeller shaft (6) comprises upper and lower portions releasably connected, said upper portion being a solid shaft and said lower portion being a tubular shaft.

1 k l l

Claims

1. A pump for removing liquid from a pit having upper and lower liquid levels comprising: a top flange for covering at least a portion of the pit; a casing defining a pumping chamber for being disposed below the upper liquid level and abovE the lower liquid level; standards depending from the top flange to support, the pumping chamber; an overhung impeller shaft extending downwardly through the top flange and an impeller attached thereto positioned within the pumping chamber; a motor mounted above the top flange for turning the impeller shaft and impeller; an extension conduit extending downwardly from the pumping chamber for terminating below the lower liquid level; and, an extension shaft pendent from the impeller and and auxiliary impeller within the extension conduit supported by the extension shaft.

2. A pump for removing liquid from a pit having upper and lower liquid levels comprising: a top flange for covering at least a portion of the pit; a pumping chamber for being disposed below the upper liquid level and above the lower liquid level comprising a casing defining a pumping chamber; standards depending from the top flange to support the pumping chamber; an overhung impeller shaft extending downwardly through an opening in the top flange and an impeller attached to said shaft and positioned within the pumping chamber; a motor mounted above the top flange for turning the impeller shaft and impeller; a protection column positioned about the impeller shaft and having a flange about the lower end for covering an opening over the top of the pumping chamber; and, an extension conduit extending downwardly from the pumping chamber through an opening in the bottom thereof for terminating below the lower liquid level comprising a pipe having a flange at the upper end, the diameters of the openings and flanges decreasing in the following order: opening in top flange, flange at bottom of column or protective tube, opening over top of pumping chamber, flange on top of extension conduit and opening on bottom of pumping chamber, whereby the impeller, impeller shaft and protection column may be removed without disturbing the standards and pumping chamber and thereafter the extension conduit may also be removed.

7. A pump according to claim 6 wherein a removable extension tube depends from the standard comprising the housing, said extension tube terminating below the lower liquid level.