llllllllillllllllIlllllllllllllllllllllllllllllllllllllllllllllllllllllllll
`USOO5553794A
`[11] Patent Number:
`
`5 553 794
`9
`9
`
`[45] Date of Patent:
`
`Sep. 10, 1996
`
`11/1985 Boudreaux ................................ .. 417/8
`4/1988 Parkinson . .. ....
`... . . .. .. 137/2
`Grace et
`......... ..
`X
`4/1990 Van Luik, Jr. et al.
`.... .. 241/36
`9/1991 Mitsch ................................. 241/4604
`
`
`
`4,551,068
`4,739,786
`
`4,919,343
`5,044,566
`
`primary Emm,',,e,_Tim0thy V_ E16},
`Attorney, Agent, or Firm——Head Johnson & Kachigian
`[Sn
`ABSTRACT
`.
`.
`.
`A
`» sewage grinder pump system for use in moving sewage,
`having a vertically oriented cylindrical pump motor housing,
`a bottom plate aflixed to and closing the pump motor
`housing, a motor supported by the bottom plate within the
`pump motor homing; the motor having a shaft extending
`through an Openmg 111 the b°“°m Plates 3 grinder Pump
`supported [0 a lower 611d Of the bottom plate and COIl1’l6Ct€d
`to the motor shaft, a closure member affixed to the pump
`motor housing top end and having a level detector receiving
`potrlioigntirogiilfing a liquidtlexiiel detector olpenintgdtlllereiiii
`ex ern
`y o
`e pump mo or ousmg, an e onga e
`1qu1
`level detector having an upper end received within the liquid
`1"V"~1 de‘e°‘°’ °P"~“i“g= and 3 °iT°“i‘ °°““e°““g the liquid
`level detector to control the motor to thereby drive the
`grinder pump in response to detected liquid level.
`
`7 Claims, 2 Drawing Sheets
`
`Ulllted States Patent
`
`[19]
`
`Oliver et al.
`
`[54] SEWAGE HANDLING SYSTEM
`
`Inventors: Darrel S_ Oliver’ Tulsa,
`Deborah C_ Wynn, Enicofi City’ Md’
`
`[73] Assignee: Tarby Inc, Claremore, Okla.
`
`[21] App]. No.: 361,292
`[22] Filed:
`Dec. 22, 1994
`[51]
`Int. Cl.5 ........................... B02C 25/00; G01F 23/00;
`F16K 21/18
`[52] U.S. c1. ........................ .. 241/36; 73/304 R; 137/386;
`137/395; 307/118; 361/178; 417/36; 241/46.01
`[58] Field of Search ............................ .. 73/304 R, 304 C;
`137/363, 386’ 392, 395, 544’ 565; 241/36,
`4601, 4602; 307/118; 361/178; 417/36
`
`[55]
`
`References Cited
`U-S- PATENT DOCUMENTS
`5/1967 Rembold ................................... 241/36
`_.___ 241/35
`5/1972 Grace __‘___.___
`
`.....
`. .... 241/36
`12/1974 Grace et al.
`9/1975 Fairell, Jr. et al.
`........ 241/46.02
`3/1977 Grace et al.
`.............................. 241/36
`
`3 313 248
`3:667:692
`3,357,517
`3,904,131
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`Franklin Electric Co., Inc.
`Exhibit 1034
`
`Franklin Electric Co., Inc.
`Exhibit 1034
`
`

`
`U.S. Patent
`
`Sep. 10, 1996
`
`Sheet 1 of 2
`
`5,553,794
`
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`U.S. Patent
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`Sep. 10, 1996
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`
`1
`SEWAGE HANDLING SYSTEM
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`5,553,794
`
`2
`
`previously issued United States Patents which are incorpo-
`rated herein by reference.
`
`
` U.S. Pat. No. INVENTOR TITLE
`
`
`This application is not related to any pending patent
`applications.
`
`CROSS-REFERENCE TO MICROFICHE
`APPENDIX
`
`This application is not related to any microfiche appendix.
`
`BACKGROUND OF THE INVENTION
`
`Most sewage systems work on the gravity system. That is,
`sewage generated in a building, home, commercial structure
`or otherwise, flows by gravity from a sewage drain extend-
`ing from a building to a sewage drain collection system, into
`sewage mains which ultimately connect to a sewage treat-
`ment plant. At the sewage treatment plant the sewage is
`treated so that environmentally acceptable elfluents can be
`released. This basic concept, of course, requires the sewage
`treatment plant to be at a lower level than all of the buildings
`in which sewage is generated. While this can be accom-
`plished in many instances, frequently there arises the need
`for a sewage treatment system which is located in such a
`way that total gravity drainage cannot be employed. For
`instance, if a home is constructed in an area wherein a hill
`or a valley lies between it and a gravity sewage draining
`system then some method must be provided for conveying
`the sewage under pressure to the point where it can be
`connected with a gravity drainage system.
`To accomplish this purpose, pressure sewage systems are
`provided for collecting sewage drained from a home or other
`type of building, or toilet facilities, to a collection point
`where the sewage is pumped, under pressure, through a line
`that ultimately connects with a gravity sewage drainage
`system or to a sewage treatment facility. By providing a
`collection system including a grinder pump, the sewage may
`not only be moved under pressure but a grinder pump makes
`it possible to use substantially smaller diameter sewage
`transport pipes extending between the sewage collection site
`and the sewage gravity flow system than can normally be
`employed where gravity alone is relied upon for moving
`sewage. Thus, the use of sewage handling systems including
`grinder pumps are well-known.
`One problem in the known sewer handling systems that
`employ a grinder pump is that of providing a control system
`for turning the pump on and off in response to the quantity
`of sewage that has collected. Control systems typically
`function based on the level of sewage in a collection vessel.
`The level can be detected by a float actuated switch, how-
`ever, the environment in which such switches function has
`made the standard liquid level detector switches unreliable.
`Another problem with known types of liquid level switches
`is that they must operate in a harsh environment for a very
`extended length of time. Due to the environment, it is a
`highly disagreeable job to enter into the area where liquid
`level switches are located to do maintenance and repair. For
`this reason, it has long been an object in the use of sewage
`grinder pumps in sewage handling systems to provide liquid
`level detector systems that are highly dependable and sub-
`stantially maintenance free. For background information
`relating to pressure sewage systems and to sewage grinder
`pump systems, reference may be had to the following
`
`15
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`20
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`25
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`30
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`35
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`45
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`50
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`55
`
`65
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`3,667,692
`3,857,517
`
`3,904,131
`4,014,475
`
`Grace
`Grace et al
`
`Farrell et al
`Grace et al
`
`Pump Storage Grinder
`Anti-Siphon and Pump Priming
`For Sewage Grinder Pump
`Pressure Sewer System
`Combined Manway and
`Collection Tank For Sewage
`Grinder
`Liquid Level Monitoring
`Assemblies
`Anti-Flooding Sewage Grinder
`Pump Liquid Level Control
`System In Separately Mounted
`Canister
`Sewage Pump With Self-
`Mitsch
`5,044,566
`Adjusting Cutters
`
`4,739,786
`
`Parkinson
`
`4,919,343
`
`Van Luik et al
`
`SUMMARY OF THE INVENTION
`
`The disclosed invention herein provides an improved
`sewage handling system. The system includes a sewage
`collection tank with sidewalls, enclosed bottom and an open
`top, the sidewall has a sewage inlet opening that is con-
`nected to a home, a building or any other type of structure
`having one or more toilets therein that produce sewage. By
`means of a gravity fluid drainage system extending from the
`home or other building, sewage is drained through the
`sewage inlet opening into the collection tank.
`The tank has a top plate with a central opening there-
`through. An electric motor driven sewage grinder pump is
`supported by a pump housing, the pump housing being
`dimensioned to removably pass through the top plate central
`opening. The pump has a discharge outlet.
`A pump housing flange is amxed to an upper end of the
`pump housing. The flange has a diameter greater than the top
`plate central opening so that the pump housing is removably
`supported within the sewage collection tank. A discharge
`conduit
`is connected to the pump discharge outlet and
`extends upwardly through an opening in the pump housing
`flange.
`An upright manway housing is provided having a lower
`open end, an open top and a sidewall. The lower end of the
`manway housing is afiixed and sealed to the top plate. Piping
`within the manway housing connects the discharge outlet
`with a housing sidewall outlet opening. A removable top
`cover closes and seals the manway housing open top.
`Electrical conductors extend through the manway housing
`sidewall and into the pump housing. The conductors have
`connection with the sewage grinder pump through a control
`circuit.
`
`A liquid level detector is supported by the pump housing
`and extends downwardly and parallel to the sewage grinder
`pump, the level detector extends within the lower sewage
`collection tank. The liquid level detector serves to detect and
`provide circuit actuation at three liquid levels. The first level
`is a liquid lower level at which the sewage grinder pump is
`turned oif. The second level is an intermediate level at which
`the sewage grinder pump is turned on. The third level is a
`high level that is reached only when the sewage grinder
`pump has failed to pump sewage from the collection tank
`upon the sewage reaching the intermediate level.
`A warning signal conductor extends through the manway
`housing sidewall and into the pump housing and connects to
`a circuit that is responsive to the liquid level detector for
`
`

`
`5,553,794
`
`3
`providing a warning signal when the liquid level in the
`sewage collection tank reaches the high level as detected by
`the third position of the liquid level detector.
`The improved sewage handling system provides a unique
`and improved way of supporting a liquid level detector and
`a sewage grinder pump housing in a unitary arrangement
`with an integral flange so that the major components of the
`sewage system can be suspended from a single structure.
`The flange is preferably formed of plastic to thereby resist
`corrosion in the harsh environment in which the system is
`employed.
`A better and more complete understanding of the inven-
`tion will be obtained from the following detailed description
`of the preferred embodiments and the claims,
`taken in
`conjunction with the attached drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is an elevational cross-sectional view of the
`improved sewage handling system showing an upper man-
`way housing with a manway cover and a lower sewage
`collection tank having within it a sewage grinder pump and
`a liquid level control.
`FIG. 2 is an enlarged cross-sectional view of the sewage
`grinder pump as supported in the pump housing that is
`suspended within the sewage collection tank and showing a
`closure member for closing the pump motor housing. The
`closure member includes an integral flange and downwardly
`extending integral
`tubular extensions. The first
`tubular
`extension receives a motor housing that contains the sewage
`grinder pump motor with the sewage grinder pump sup-
`ported at the motor housing lower end. The other closure
`member tubular extension receives a liquid level detector
`that is supported adjacent to and paralleled to the motor
`housing.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`Referring now to the drawings and first to FIG. 1, a
`preferred embodiment of the improved sewage handling
`system of this invention is illustrated. The system includes
`a manway housing 10 that has an upper open end 12
`positioned at ground level 14. The upper open end 12 is
`closed by manway cover 16.
`
`The lower end 18 of manway housing 10 is supported by
`a plate 20 and below it is a sewage collection tank 22. The
`upper open top 24 of sewage collection tank 22 attaches to
`plate 20. The bottom 26 of sewage collection tank 22 is
`closed, and the bottom portion is preferably tapered at 28.
`Positioned within the interior of sewage collection tank 22
`is a grinder pump housing and grinder pump assembly,
`generally indicated by the numeral 30, that is illustrated in
`greater detail in the eross—sectional view of FIG. 2, to which
`reference will now be made.
`
`The grinder pump assembly 30 includes a pump housing
`32 having an open top end 34, the pump housing lower end
`36 being closed by bottom plate 38 that has an opening 40
`therethrough. Positioned within housing 32 is a pump motor
`42 having a shaft 44 that extends through opening 40.
`Aflixed to the lower end of bottom plate 38 is a grinder pump
`46. The pump has a lower grinding head 48 and, above that,
`a positive displacement progressing cavity pump 50. Above
`the progressing cavity pump is a discharge cavity 52 having
`an outlet opening 54. Within discharge cavity 52 a spring
`actuated seal system 56 is positioned about shaft 44 to
`
`4
`
`prevent sewage from entering the interior of pump housing
`32 through opening 40.
`To support the pump housing 32 with its enclosed pump
`motor 42 and attached grinder pump 46 within sewage
`collection tank 22, a closure member 58 is employed. The
`closure member 58, which preferably is cast, of plastic
`material, has an integral radially extending flange 60 that,
`when the unit is installed, rests on the top of plate 20 as
`shown in FIG. 1. The entire grinder pump assembly 30 is
`removable through an opening 62 in plate 20. As further
`seen in FIG. 2, closure member 58 includes a downwardly
`extending tubular portion 64 that telescopically receives
`upper end 34 of pump housing 32. An integral septum 66
`formed as a part of closure member 58 functions to close
`upper end 34 of pump housing 32. Pump housing 32 may be
`secured to downwardly extending tubular portion 64 by
`threaded attachment or by sealably bonding housing 32 to
`tubular portion 64 so as to create an air tight environment for
`pump motor 42. In order to test the integrity of the watertight
`seals after assembly, an air valve 68 is placed into septum
`66. Air valve 68 is of the type employed for pressuring
`tube-less tires so that a source of air pressure may be applied
`through the valve to form positive air pressure within the
`interior of pump housing 32.
`An important aspect of closure member 58 is the provi-
`sion of an integral liquid level switch detector portion 70
`providing an opening 72 having a lower end 74. Supported
`within opening 72 is the upper end 76 of an elongated liquid
`level detector 78. Detector 78 has provisions for providing
`electrical signals in response to three fluid levels. The first is
`a lower band 80. A signal is generated when the level falls
`below lower band 80. This signal is used in a circuit to turn
`pump motor 42 off, if the motor is running to pump fluid
`from collection tank 22. A second level detector band 82 is
`spaced above lower band 80. An electrical signal generated
`by the switch when liquid level reaches band 82 functions to
`turn motor 42 on to thereby energize pump 46 to reduce the
`level of fluid within sewage collection tank 22. A third
`detector band 84 spaced above second detector band 82
`provides an electrical signal used for indicating an emer~
`gency condition. That
`is, when the liquid level within
`sewage collection tank 22 reaches the level of third band 84,
`a warning or danger signal is provided since the fact that the
`level has reached that which is detected by the third detector
`band 84 indicates that the system has not functioned to
`maintain the proper maximum level within collection tank
`22. Therefore,
`some problem exists which must be
`addressed, otherwise sewage will continue to collect until
`collection tank 22 is completely filled, at which time it will
`back up in the sewage collection lines leading to the tank
`and, ultimately, into toilet facilities from which the sewage
`is originated.
`Detector bands 80,82 and 84 of level detector 78 can
`function in a variety of ways to indicate fluid level. A
`common means employed for detecting fluid level
`is if
`bands 80, 82 and 84 are conductive so that conductance of
`a circuit increases when the fluid level contacts the bands.
`Bands 80, 82 and 84 may function to detect liquid level by
`change in capacitance that occurs in the presence of the
`liquid to provide signal information to circuitry for control
`of the operation of motor pump 42 and for providing a
`warning signal.
`The location of septum 66 within closure member 58,
`which is spaced well below flange 60, provides an internal
`space 86 in which a control circuit 88 is positioned. The
`control circuit has conductors 90 extending to detachable
`connector 92 which in turn connects with conductors 94 and
`96 extending to level detector 78 and motor 42 respectively.
`
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`5,553,794
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`A cover plate 98 removably closes the upper end of
`closure member 58, the cover plate having a seal conductor
`passageway 100 therein whereby a cable 102 passes. Cable
`102 serves to supply electrical energy for circuit 88 by which
`motor 42 is operated as well as to carry a conductor for
`providing an emergency signal. An emergency signal can be
`generated in a remote location, such as within a house from
`which sewage is taken to drain into sewage collection tank
`22. The signal device (not shown) may be a noise generator,
`such as a bell or horn or a light.
`As seen both in FIGS. 1 and 2, there is a sewage outlet
`conduit 104 that extends through an opening in flange 60,
`conduit 104 being connected at its lower end to pump outlet
`opening 54. A check valve 106 is provided within conduit
`104 to resist the flow of sewage back through the pump and
`into sewage collection tank 22 when motor 42 is not
`energized. As seen in FIG. 1, within manway housing 10, a
`manual control valve 108 is provided in line 104 so that
`when it is necessary to remove the grinder pump assembly
`30, valve 108 can be closed to prevent sewage from backing
`up through the line.
`A connection 110 is attached to the end of conduit 104 to
`receive a sewage conduit (not shown) by which sewage
`under pressure is carried away from the system. Such
`sewage conduit typically traverses a distance necessary so
`that the outer end thereof is connected to a gravity sewage
`collection system or other sewage disposal system.
`As shown in FIG. 1, sewage collection tank 22 has a
`sewage inlet 112. A sewage drain pipe (not shown) extend-
`ing from a home, office, shop or other type of building
`having one or more toilet facilities connects by gravity flow
`to sewage inlet 112 where sewage is delivered into the
`interior of sewage collection tank 10.
`Positioned within the interior of manway housing 10 is
`junction box 114 by which flexible conductor 102 is con-
`nected to conduits 116 and 118. Conduit 116 connects to a
`power source whereby electrical energy is supplied to pump
`motor 42 and circuitry 88. Conduit 118 contains conductors
`for carrying an emergency indicating signal when the fluid
`level within sewage collection tank 22 reaches third band 84
`of level detector 78 to provide a warning signal.
`The sewage collection system herein provides a unique,
`economical and highly effective way of mounting a pump
`motor housing 32 in conjunction with a vertical liquid level
`detector 78, both supported by an integral closing member
`58 in an arrangement wherein these components are sup-
`ported in contiguous side—by-side relationship for easy
`assembly and for removal for repair or maintenance. The
`improved combination of a liquid level detector and motor
`housing all mounted and extending from the same integral
`closure member 58 assures simplicity of installation and
`reduces the possibility of failure of the system. The system
`of this disclosure is particularly advantageous when com-
`pared with systems that employ float actuated liquid detec-
`tors with their attendant mechanical operating features that
`are subject to wear and failure.
`The claims and the specification describe the invention
`presented and the terms that are employed in the claims draw
`their meaning from the use of such terms in the specification.
`The same terms employed in the prior art may be broader in
`meaning than specifically employed herein. Whenever there
`is a question between the broader definition of such terms
`used in the prior art and the more specific use of the terms
`herein, the more specific meaning is meant.
`While the invention has been described with a certain
`
`degree of particularity, it is manifest that many changes may
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`be made in the details of construction and the arrangement
`of components without departing from the spirit and scope
`of this disclosure. It is understood that the invention is not
`limited to the embodiments set forth herein for purposes of
`exemplification, but is to be limited only by the scope of the
`attached claim or claims, including the full range of equiva-
`lency to which each element thereof is entitled.
`What is claimed is:
`
`1. An improved sewage handling system comprising:
`a sewage collection tank having a sidewall, a closed
`bottom and an open top, the sidewall having a sewage
`inlet opening therein;
`a top plate closing said collection tank open top and
`having a central opening therethrough;
`an electric motor driven pump supported by a pump
`housing,
`the pump housing being dimensioned to
`removably pass through said top plate central opening,
`the pump having a discharge outlet;
`a pump housing flange afiixed to an upper end of said
`pump housing having a diameter greater than said top
`plate central opening whereby said pump housing is
`removably supported within said sewage collection
`tank;
`
`a discharge conduit connected to said pump discharge
`outlet and extending upwardly through an opening in
`said pump housing flange;
`an upright manway housing having a lower open end, an
`open top and a sidewall, the lower end being sealably
`affixed to said top plate, the sidewall having an outlet
`opening therein;
`
`piping within said manway housing removably connect-
`ing said discharge conduit with said sidewall outlet
`opening;
`
`atop cover removably and sealably closing said manway
`housing open top;
`electrical conductors extending sealably through said
`manway housing sidewall and into said pump housing
`having connection with said pump through a control
`circuit;
`
`a liquid level detector supported by said pump housing
`and extending downwardly and parallel to said pump
`within said lower sewage collection tank, the liquid
`level detector having means to detect and provide
`circuit actuation at three liquid levels, the first level
`being a liquid lower level at which said pump is turned
`off, the second being an intermediate level at which
`said pump is turned on, and the third being a high level
`that is reached only when said pump has failed to pump
`sewage from collection tank upon the sewage level
`reaching said intermediate level; and
`
`a warning signal conductor extending sealably through
`said manway housing sidewall and into said pump
`housing and connected to said liquid level detector for
`providing a warning signal when the liquid level in said
`sewage collection tank reaches said high level.
`2. A sewage pump system for use in moving sewage,
`comprising:
`
`a vertically oriented cylindrical pump motor housing
`having a sidewall and open top and bottom end;
`a bottom plate afiixed to and closing said pump motor
`housing bottom end and having an opening there-
`through;
`
`a motor supported by said bottom plate within said pump
`motor housing, the motor having a shaft extending
`through said bottom plate opening;
`
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`5,553,794
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`a pump supported to a lower end of said bottom plate and
`connected to said motor shaft, said grinder pump hav-
`ing an intake and an outlet opening, the outlet opening
`being connected to a conduit for the passage of sewage
`therethrough;
`a closure member afiixed to said pump motor housing top
`end, the closure member having a level detector receiv-
`ing portion providing a liquid level detector opening
`therein externally of said pump motor housing;
`an elongated liquid level detector having an upper and a
`lower end, the upper end being received within said
`liquid level detector opening, the liquid level detector
`having means to detect the level of liquid exterior of
`said pump motor housing; and
`circuit means connecting with said liquid level detector to
`control said motor to thereby drive said pump in
`response to detected liquid level.
`3. A sewage pump system according to claim 2 where said
`closure member has an upper end and a lower end and
`includes a tubular extension on the lower end telescopically
`engaging said pump motor housing top end.
`
`l0
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`4. A sewage pump system according to claim 3 wherein
`said closure member has a tubular upper portion separated
`from said lower end tubular extension by a septum, the
`septum forming a top closure of said motor housing.
`5. A sewage pump system according to claim 4 wherein
`said circuit means is contained, at least in part, within said
`closure member tubular upper portion.
`6. A sewage pump system according to claim 2 wherein
`said tubular level detector comprises:
`an elongated vertical body having an upper end and a
`lower end, and having a first level detecting band
`positioned on said body adjacent said bottom end for
`indicating a lower liquid level and a second level
`detecting band on said body spaced above said first
`band for indicating an upper fluid level.
`7. A sewage system according to claim 6 including a third
`level detecting band on said body spaced above said second
`band for indicating an emergency fluid level.
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