Lower grinder pump tank

Information

  • Patent Grant
  • 6299080
  • Patent Number
    6,299,080
  • Date Filed
    Friday, April 9, 1999
    25 years ago
  • Date Issued
    Tuesday, October 9, 2001
    23 years ago
  • Inventors
  • Examiners
    • Husar; John M.
    Agents
    • Law Offices of Royal W. Craig
Abstract
An improved horizontally-disposed lower tank for a grinder pump unit, the lower tank being formed of at least one section of corrugated pipe, and at least one aperture formed therein for mounting a grinder pump unit. The lower tank is buried lengthwise in the ground with the aperture(s) directed upwardly. A transition collar is fitted into each aperture of the cylindrical lower tank for mounting grinder pump unit(s) thereon. The lower tank is buried lengthwise in the ground. The horizontally-disposed lower collection tank can accommodate one or more grinder pump units mounted to the inside of the single collection tank, and readily available parts (such as, for instance, the Series 2000—60 gallon tank e.g., from Environment One Corp.) can be used for the grinder pump unit. The horizontal lower tank creates a storage volume that is far in excess of existing capabilities, and the submerged lower tank is structurally sound and needs no concrete or other reinforcement, thereby lowering the cost of both manufacturing and installation.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to sewage grinder pumps and, more particularly, to an improved horizontal lower collection tank assemblage for a grinder pump station that can accommodate one or more grinder pump units mounted to the inside of the single collection tank.




2. Description of the Background




Sewage grinder pump stations are well-known, as exemplified in U.S. Pat. No. 5,562,254 issued to Sleasman et al. On Oct. 8, 1996 (which specification is incorporated by reference herein).





FIG. 1

is a perspective drawing from the '254 patent illustrating the grinder pump station


10


, and

FIG. 2

is a cross-section drawing from the '254 patent illustrating lower tank portion


16


formed by a cylindrical non-corrugated inner wall


52


and a corrugated outer wall


54


.





FIG. 3

illustrates how the prior art grinder pump station


10


of

FIGS. 1 and 2

is installed in the ground.




As seen throughout

FIGS. 1-3

and as fully described in the '254 patent, this grinder pump station


10


is positioned substantially vertically in the ground. Grinder pump station


10


includes a lid assembly


22


, an upper tank portion


14


, a transition section


18


, a lower tank portion


16


, and a base


32


. The outer side walls of upper tank portion


14


and lower tank portion


16


are corrugated, while the outer side wall


17


of transition section


18


is smooth. Extending through side wall


17


of transition section


18


is an inlet opening


20


through which sewage enters grinder pump station


10


, and a discharge opening


19


, through which processed sewage exits grinder pump station


10


. Attached to this upper tank portion


14


is a lid assembly


22


. Lid assembly


22


includes the electrical and ventilation interfaces of the grinder pump station, as more fully described hereinafter, and an access hatch


24


for allowing interior access. A base


32


is secured to the lower portion


16


of grinder pump station


10


. Mounted within grinder pump station


10


is a grinder pump unit


34


. Grinder pump unit


34


includes a grinder head


36


for pulverizing sewage. A grinder pump


39


is secured to grinder head


36


for pumping ground sewage through grinder pump station


10


. Grinder pump


38


includes a discharge housing


40


, which is joined to a discharge outlet pipe


42


. A sealed control housing


44


houses the controls for grinder pump


34


, and underneath housing


44


, a motor housing casting


47


houses an electric motor (not shown) for powering both grinder pump


38


and grinder head


36


. Grinder pump unit


34


employs one or more sensing tubes


46


to sense pressure variations by measuring increases in the level of sewage collected in grinder pump station


10


. Upon the attainment of a predetermined sewage level, the motor within motor housing casting


47


is energized. The sewage collected in grinder pump station


10


is then be ground by grinder head


36


and is pumped by grinder pump


38


from discharge housing


41


to discharge outlet pipe


42


. From discharge outlet pipe


42


, the processed sewage travels to a remote location, e.g., to a pressure sewage main and ultimately to a sewage treatment plant. The entire above-described grinder pump unit is commercially available as the Model 2000 Series from Environment One Corp., Schenectady, N.Y.




With particular reference to the tank portions


14


and


16


of grinder pump station


10


, it can be seen that the upper tank portion


14


and lower tank portion


16


are identical in every respect apart from their relative height. Both upper tank portion


14


and lower tank portion


16


have a substantially cylindrical non-corrugated inner wall


52


secured to a substantially cylindrical corrugated outer wall


54


. The corrugations of the outer wall


54


form a series of alternating crests


56


, ridges and troughs


58


. Each trough


58


of corrugated wall


54


is secured, during the manufacturing process, to inner wall


52


. An extrusion method of manufacture can be employed to form the corrugated configuration, wherein the cylindrical corrugated outer wall


54


and cylindrical inner wall


52


integrally form double walled upper tank portion


14


and lower tank portion


16


.




A transition section


18


separates the upper tank


14


from lower tank


16


. Transition section


18


is substantially cylindrical in shape, and has a non-corrugated outer wall to facilitate the formation of one or more inlet openings


20


and discharge openings


19


through its sides, and has an enlarged axial opening extending therein. Transition section


18


includes structure for positioning and aligning grinder pump unit


34


in grinder pump station


10


. The inner diameter of transition section \


18


is defined by the axial opening, and the outer diameter is defined by outer side wall


17


. An internal conical wall


118


forms the upper reservoir portion of transition section


18


, while conical wall


118


flows inward from the outer diameter to a proximity near the inner diameter of the transition section. The conical shape provides structural stiffness for transition section


18


and facilitates the insertion of grinder pump unit


34


into the axial opening or transition section


18


. The grinder pump stations, lower tank portions, and transition sections as described above and as illustrated in the '254 patent are commercially available from Environment One Corp., Schenectady, N.Y.




It is noteworthy that the above-described design is limited to the illustrated vertical/coaxial configuration of the upper and lower tank portions


14


and


16


of grinder pump station


10


. This configuration ostensibly allows for easy field height adjustability, in small increments. However, the vertical configuration can only accommodate a single grinder pump unit, and the overall storage volume is very limited. Moreover,

FIG. 3

shows the use of concrete reinforcement


143


for the submerged tank. Concrete reinforcement


143


is necessary to support the vertical and coaxial configuration of the upper and lower tank portions


14


and


16


. A concrete truck must somehow gain access to the site, and this greatly increases the cost of manufacturing and installation.




SUMMARY OF THE INVENTION




It is, therefore, an object of the present invention to provide an improved horizontal lower collection tank for a grinder pump station that can accommodate one or more grinder pump units mounted to the inside of the single collection tank.




It is another object to allow readily available parts (such as, for instance, the series 2000—60 gallon tank e.g., from Environment One Corp., Schenectady, N.Y.) to be used in a lower tank design with an inlet at the top of the wet well thus creating a storage volume that is far in excess of existing capabilities.




It is another object to facilitate submersion of the tank no matter the volume without the need for concrete or other reinforcement, thereby lowering the cost of both manufacturing and installation.




It is another object to allow the manufacturer to mount as many grinder pumps to a given tank as the project may require, and to thereby increase the discharge rate of the given tank.




According to the present invention, the above-described and other objects are accomplished by providing an improved horizontally-disposed lower tank for a grinder pump unit, the lower tank including at least one section of corrugated pipe, and at least one aperture formed therein for mounting a grinder pump unit. The lower tank is buried lengthwise in the ground with the aperture(s) directed upwardly. A transition collar is fitted into each aperture of the cylindrical lower tank for mounting grinder pump unit(s) thereon.











BRIEF DESCRIPTION OF THE DRAWINGS




Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiment and certain modifications thereof when taken together with the accompanying drawings in which:





FIG. 1

is a prior art perspective drawing of a grinder pump station


10


having a lower tank portion


16


with a cylindrical non-corrugated inner wall


52


and a corrugated outer wall


54


.





FIG. 2

is a cross-section of the prior art grinder pump station


10


of FIG.


1


.





FIG. 3

is a side perspective view illustrating the prior art grinder pump station


10


of

FIGS. 1 and 2

as installed in the ground and reinforced by a concrete collar


143


.





FIG. 4

is a cross-sectional view of an improved lateral-mount lower tank portion


160


with two grinder pump units mounted to the inside according to one embodiment of the present invention.





FIG. 5

is a cross-sectional view of another embodiment of the lateral-mount lower tank portion


260


employing larger diameter polyethylene pipe as a simplex pumping station with modifications to allow the single pump to be lowered further into the tank.





FIG. 6

is a cross-sectional view of another embodiment of an angled lower tank portion


360


.





FIG. 7

is a cross-sectional view of the improved lateral-mount lower tank portion


460


with four grinder pump units mounted to the inside according to another embodiment of the present invention.





FIG. 8

is a top perspective view of a lateral-mount lower tank portion


560


which employs a cross-fitting to join four separate sections of polyethylene pipe in an “X” configuration, thereby allowing the use of four pumps in a very tight area.





FIG. 9

is a cross-sectional view of a simplex lateral-mount lower tank portion


160


as in the duplex embodiment of

FIG. 5

, with a more detailed illustration of a conventional transition piece


16


.





FIG. 10

is a cross-sectional view of a lateral-mount lower tank portion


160


as in

FIG. 9

with no transition piece.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS





FIG. 4

is a cross-sectional view of an improved lateral-mount lower tank portion


160


with two grinder pump units


10




a


&


10




b


mounted to the inside according to one embodiment of the present invention.




Both grinder pump stations


10




a


&


10




b


are identical to the grinder pump stations


10


of the above-described '254 patent, and both are readily available components (e.g., the Series 2000 of Environment One Corp., Schenectady, N.Y.). However, rather than a vertical and coaxial configuration of upper and lower tank portions


14


and


16


(as shown in FIGS.


1


-


3


), a modified lower tank portion


160


is configured in the horizontal configuration shown. This results in a horizontal mounting capability, and numerous alternative tank configurations (including the duplex configuration shown) become possible.




Both upper tank portions


14


and lower tank portion


160


are formed in a known manner from a substantially cylindrical non-corrugated inner wall


162


secured to a substantially cylindrical corrugated outer wall


164


. The corrugations of the outer wall


164


form a series of alternating crests, ridges and troughs. Each trough of the corrugated outer wall


164


is secured, during the manufacturing process, to cylindrical non-corrugated inner wall


162


. Both tank portions


14


and


160


may be constructed from a thermoplastic, such as high density polyethylene. An extrusion method of manufacture can be employed to form the corrugated configuration, wherein the cylindrical corrugated outer wall


164


and cylindrical inner wall


162


integrally form double walled lower tank portion


160


. Alternatively, pre-fabricated pipe is readily commercially available, and other wall configurations may be used. For example, smooth wall plastic or fiberglass pipe may be used. In either case a 24″ diameter pipe is suitable for the upper tank portions


14


, while 36 through 48″ diameter pipe is suitable for the lower tank portion


160


. The larger diameter lower polyethylene tank


160


is installed horizontally, thus becoming structurally more sound and large enough in both length and width as to not require any concrete collars for either strength or ballast.




The standard 4″ inlet


20


and the 1 ¼″ discharge


19


of the grinder pump units


10




a


and


10




b


are pre-formed in commercially available products identified as transition sections


18


(these are also available as part number 2010 from Environment One Corp.). The lower tank


160


is defined by two circular upper apertures at positions corresponding to the grinder pump units


10




a


and


10




b


. The transition sections


18


for both grinder pump units


10




a


and


10




b


are fitted into the two upper apertures, and each transition section


18


separates the respective upper tank


14


from lower tank


16


. Transition sections


18


are substantially cylindrical in shape, have a non-corrugated outer wall to facilitate one or more inlet or discharge openings


20


, and they have an enlarged axial opening inside. Transition sections


18


include structures for positioning and aligning the internal grinder pump mechanisms in grinder pump stations


10




a


and


10




b


. An internal conical wall


118


forms the upper reservoir portion of transition section


18


, while conical wall


118


flows inward from the outer diameter to a proximity near the inner diameter of the transition section. The conical wall


118


provides structural stiffness for transition section


18


and facilitates the insertion of grinder pump unit into the axial opening or transition section


18


. The single horizontal lower collection tank


160


can accommodate both grinder pump units


10




a


and


10




b


mounted to the inside of the single tank


160


. All parts used in the system are readily available, yet the overall storage volume far exceeds existing capabilities. Moreover, the manufacturer can mount as many grinder pumps


10




a


,


10




b


. . .


10


−n as desired to a given lower tank


160


, thereby increasing the discharge rate of the given tank.





FIG. 5

is a cross-sectional view of another embodiment of the lateral-mount lower tank portion


260


employing larger diameter polyethylene pipe (e.g., from 54 to 72″ diameter) in a simplex pumping station configuration with modifications to allow a single pump unit


10


to be lowered further into the lower tank


260


. The pump unit


10


is lowered further into the tank by the use of a straight piece of polyethylene pipe


30


inserted between the


2010


transition piece


16


and the standard upper tank section


14


.





FIG. 6

is a cross-sectional view of another embodiment that employs an angled lower tank portion


360


. As in the embodiment of

FIGS. 4 & 5

, a section of larger diameter polyethylene pipe is used for the lower tank


360


in a simplex pumping station configuration, and an angled aperture is cut at the top of the lower tank


360


such that the transition piece


18


provides an angled ingress into the polyethylene pipe of the lower tank


360


. This way, when buried, the larger diameter lower tank


360


is sloped downward to direct sewage toward the pump unit


10


.





FIG. 7

is a cross-sectional view of another embodiment of the improved lateral-mount lower tank portion


460


with four grinder pump units


10




a


-


10




d


mounted to the inside. A longer section of lower corrugated pipe is used for the lower tank


460


and in conjunction with four transition pieces


18


(e.g., Environment One Corp Model 2010). This illustrates how the use of longer lower tanks


460


enable many more pump units


10


to be installed into a single tank


460


. Conventional baffles


22




a


-


22




c


may be installed (here one high baffle


22




b


and two low baffles


22




a


and


22




c


), and in this manner the lower tank


460


can be sectioned to operate as a duplex unit with each pair of sectioned pump units


10




a


&


10




b


,


10




c


&


10




d


serving as a backup for each other.





FIG. 8

is a top perspective view of a lateral-mount lower tank portion


560


which employs a cross-fitting


565


to join four separate sections


28




a


-


28




d


of polyethylene pipe in an “X” configuration, thereby allowing the use of four pump units


10




a


-


10




d


in a very tight area. The cross-fitting


565


may be a conventional polyethylene pipe section having four conduits of the same diameter as the polyethylene pipe sections


18




a


-


18




d.







FIG. 9

is a cross-sectional view of a simplex lateral-mount lower tank portion


160


(as in the duplex embodiment of FIG.


4


), with a more detailed illustration of a conventional transition piece


18


. The curvature of the large diameter pipe


28


around the aperture proximate the transition piece


18


is shown, whereby the pipe


28


dips enough to allow for the four inch or six inch warp in the transition piece. Therefore, the entire volume of the lower tank


160


is below the aperture so that the entire volume of the lower tank


160


ran be used for storage.





FIG. 10

is a cross-sectional view of a lateral-mount lower tank portion


160


as in

FIG. 9

with no transition piece at all. Instead, a section of smooth wall polyethylene pipe


25


is employed and an inexpensive lid


27


is used. This configuration can be used with the Environment One AMGP pump or any other submersible pump to achieve a higher flow rate than would otherwise be available.




Having now fully set forth the preferred embodiments and certain modifications of the concept underlying the present invention, various other embodiments of the lateral-mount lower tank as well as certain variations and modifications thereto may obviously occur to those skilled in the art upon becoming familiar with said underlying concept. For instance, the lower tank need not be corrugated high density polyethylene. Alternately, it may be formed of smooth wall plastic or fiberglass pipe. It is to be understood, therefore, that the invention may be practiced otherwise than as specifically set forth herein.



Claims
  • 1. A sewage grinder pump station, comprising:a grinder pump unit; an upper tank formed as a cylindrical section and having a first axis, said upper tank being substantially vertically oriented and closed at the top; a lower tank in communication with said upper tank, the lower tank being formed from at least one cylindrical section of pipe having a second axis orthogonal to said first axis, and said lower tank having an upward aperture in its perimeter for mounting said upper tank; whereby said grinder pump unit is housed within said upper tank and lower tank.
  • 2. The sewage grinder pump station according to claim 1, wherein the upward aperture in the lower tank is circular for mounting the cylindrical lower tank vertically thereon.
  • 3. The sewage grinder pump station according to claim 2, whereby said lower tank is buried lengthwise in the ground with said aperture directed upwardly.
  • 4. The sewage grinder pump station according to claim 3, further comprising a transition collar fitted into said aperture of the cylindrical lower tank for mounting the bottom of the cylindrical lower tank.
  • 5. The sewage grinder pump station according to claim 1, further comprising a plurality of grinder pump units, a corresponding plurality of upper tanks each being formed as a cylindrical section, substantially vertically oriented and closed at the top, and a single a lower tank in communication with all of said upper tanks, the lower tank being formed from at least one section of pipe with a plurality of upward apertures therein for mounting said upper tanks.
  • 6. The sewage grinder pump station according to claim 5, further comprising at least one baffle partially subdividing the interior of said lower tank into separate areas for each of said plurality of grinder pump units.
  • 7. The sewage grinder pump station according to claim 5, wherein said single lower tank is formed from a linear section of pipe with a plurality of upward apertures spaced lengthwise for mounting said upper tanks.
  • 8. The sewage grinder pump station according to claim 5, wherein said single lower tank is formed from a union of two linear sections of pipe, thereby forming four chambers each having an upward aperture formed therein for mounting a corresponding upper tank.
  • 9. The sewage grinder pump station according to claim 1, wherein the upward aperture in the lower tank is spherical for mounting the bottom of the cylindrical lower tank at an angle.
  • 10. The sewage grinder pump station according to claim 1, wherein said lower tank further comprises at least one section of corrugated pipe.
  • 11. The sewage grinder pump station according to claim 10, wherein said corrugated lower tank is formed of plastic.
  • 12. The sewage grinder pump station according to claim 11, wherein said corrugated lower tank is formed of high-density polyethylene.
  • 13. The sewage grinder pump station according to claim 10, wherein said corrugated lower tank is formed of fiberglass.
  • 14. A tank for a sewage grinder pump station, comprising an upper tank formed as a substantially vertically oriented cylindrical section closed at the top, and a lower tank formed as a substantially horizontally oriented cylindrical section closed at both ends and coupled to said upper tank.
  • 15. The tank for a sewage grinder pump station according to claim 14, wherein said lower tank is formed from at least one section of pipe with an upward aperture therein for mounting said upper tank.
  • 16. The tank for a sewage grinder pump station according to claim 15, wherein the upward aperture in the lower tank is circular for mounting the cylindrical lower tank vertically thereon.
  • 17. The tank for a sewage grinder pump station according to claim 15, further comprising a transition collar fitted into said aperture of the cylindrical lower tank for mounting the bottom of the cylindrical lower tank.
  • 18. The tank for a sewage grinder pump station according to claim 15, wherein said single lower tank is formed from a union of two linear sections of pipe, thereby forming four chambers each having an upward aperture formed therein for mounting a corresponding upper tank.
  • 19. The tank for a sewage grinder pump station according to claim 14, further comprising a plurality of grinder pump units, a corresponding plurality of upper tanks each being formed as a cylindrical section, substantially vertically oriented and closed at the top, and a single a lower tank in communication with all of said upper tanks, the lower tank being formed from at least one section of pipe, closed at both ends, and with a plurality of upward apertures therein for mounting said upper tanks.
  • 20. The tank for a sewage grinder pump station according to claim 19, further comprising at least one baffle partially subdividing the interior of said lower tank into separate areas for each of said plurality of grinder pump units.
CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is based on provisional application No. 60/081,134 for “LOWER GRINDER PUMP TANK”; filed Apr. 9, 1998.

US Referenced Citations (8)
Number Name Date Kind
3920550 Farrell, Jr. et al Nov 1975
4014475 Grace et al. Mar 1977
4822213 Grace et al. Apr 1989
4904387 Jordan Feb 1990
4919343 Luik, Jr. et al. Apr 1990
5337966 Francis et al. Aug 1994
5480548 Daigger et al. Jan 1996
5996621 Hagiwara et al. Dec 1999
Provisional Applications (1)
Number Date Country
60/081134 Apr 1998 US