US3667692A — Pump storage grinder

Claim 1

Independent Claim 752 words

Apparatus for comminuting and pumping semi-fluid material, comprising: a single piece upwardly opening cup-shaped receptacle having an outwardly extending peripheral flange at its open end provided with a plurality of flange holes extending in the axial direction of the receptacle; an inlet pipe extending through said receptacle, freely opening into the interior of said receptacle and having a coupling exteriorly of said receptacle; a single piece annular cover peripherally overlying said receptacle flange and having holes axially aligned with said flange holes; an annular gasket between said flange and said annular cover; fastener means extending through said aligned holes to clamp said annular cover and said flange sealingly together; a one-piece generally annular control housing having an annular outer flange peripherally overlapping the inside of said annular cover and further having a depending annular wall extending into said receptacle; an outlet pipe extending through one of said control housing annular flange and said annular cover; a cover plate releasably secured to and closing the upper end of said control housing; said control housing having a downwardly extending cylindrical coupling portion and a downwardly facing shoulder; a tube having an upper end abutting against said shoulder and telescopically engaging said cylindrical coupling portion; seal means between said tube and said cylindrical coupling portion; band means surrounding and clamping said tube radially tightly against said cylindrical coupling portion; a one-piece generally annular head telescopically engaging at its upper end with the lower end of said tube and having sealing means therebetween; a plurality of bolt means, each engaging said control housing at one of its ends and engaging said head at its other end for tightly clamping said tube between said head and said control housing; an electric motor within said tube and having A rotatable shaft extending vertically downwardly and through said head; bearing means rotatably receiving said shaft and mounting said motor on said head; sealing means for preventing the passage of fluid upwardly through said head into said tube; said cover plate, said control housing, said tube, said head, said motor shaft, and said sealing means forming a sealed motor and control chamber within said receptacle; an outlet passage extending radially through said head portion exteriorly of said sealed motor and control chamber; conduit means extending between said outlet passage and said outlet pipe; one-way valve means clamped directly between said conduit means and said head for allowing fluid flow only outwardly from said head; a one-piece annular pump housing rigidly secured to the lower end of said head and having said motor shaft extending axially therethrough; a resilient internally helically threaded annular pump casing clamped between said pump housing and said head; helical thread means drivingly on said motor shaft within said pump casing for cooperation therewith during rotation of said motor shaft to form means for pumping fluid upwardly through said pump housing portion, into said head, through said outlet passage, through said one-way valve means through said conduit means, and outwardly through outlet pipe; said pump housing having an annular lower impeller casing portion; an imperforate impeller disc drivingly secured to said motor shaft below said pumping means and within said impeller casing; an annular inlet shroud having a lower continuously smooth internal peripheral wall being rigidly secured below and to said pump housing; a comminuting ring tightly clamped between said pump housing and said inlet shroud; said comminuting ring having an inner annular wall substantially axially aligned with the periphery of said impeller disc; said inner annular wall consisting essentially of a lower continuously smooth wall portion and a second upper comminuting wall portion composed of a plurality of peripherally arranged axial comminuting slots; a plurality of impeller blades on the lower face of said impeller disc extending downwardly and generally radially aligned with said comminuting slots; said comminuting slots extending from a distance substantially below said impeller blades axially upwardly for a distance substantially above said impeller blades; pressure actuated control means for starting and stopping said motor and being contained within said control housing; sealed conduit means extending from said pressure actuated control means downwardly and opening adjacent said inlet shroud, but upwardly from the lower terminal edge of said inlet shroud so that fluid sucked in by said pumping means will have an axial velocity component away from said conduit means opening for preventing clogging; and a fluid vent pipe extending through said control housing portion to provide free air passage from the upper portion of said receptacle to the exterior of said receptacle.

Claim 2

Dependent Claim 752 words

Apparatus for comminuting and pumping semi-fluid material, comprising: a single piece upwardly opening cup-shaped receptacle having an outwardly extending peripheral flange at its open end provided with a plurality of flange holes extending in the axial direction of the receptacle; an inlet pipe extending through said receptacle, freely opening into the interior of said receptacle and having a coupling exteriorly of said receptacle; a single piece annular cover peripherally overlying said receptacle flange and having holes axially aligned with said flange holes; an annular gasket between said flange and said annular cover; fastener means extending through said aligned holes to clamp said annular cover and said flange sealingly together; a one-piece generally annular control housing having an annular outer flange peripherally overlapping the inside of said annular cover and further having a depending annular wall extending into said receptacle; an outlet pipe extending through one of said control housing annular flange and said annular cover; a cover plate releasably secured to and closing the upper end of said control housing; said control housing having a downwardly extending cylindrical coupling portion and a downwardly facing shoulder; a tube having an upper end abutting against said shoulder and telescopically engaging said cylindrical coupling portion; seal means between said tube and said cylindrical coupling portion; band means surrounding and clamping said tube radially tightly against said cylindrical coupling portion; a one-piece generally annular head telescopically engaging at its upper end with the lower end of said tube and having sealing means therebetween; a plurality of bolt means, each engaging said control housing at one of its ends and engaging said head at its other end for tightly clamping said tube between said head and said control housing; an electric motor within said tube and having A rotatable shaft extending vertically downwardly and through said head; bearing means rotatably receiving said shaft and mounting said motor on said head; sealing means for preventing the passage of fluid upwardly through said head into said tube; said cover plate, said control housing, said tube, said head, said motor shaft, and said sealing means forming a sealed motor and control chamber within said receptacle; an outlet passage extending radially through said head portion exteriorly of said sealed motor and control chamber; conduit means extending between said outlet passage and said outlet pipe; one-way valve means clamped directly between said conduit means and said head for allowing fluid flow only outwardly from said head; a one-piece annular pump housing rigidly secured to the lower end of said head and having said motor shaft extending axially therethrough; a resilient internally helically threaded annular pump casing clamped between said pump housing and said head; helical thread means drivingly on said motor shaft within said pump casing for cooperation therewith during rotation of said motor shaft to form means for pumping fluid upwardly through said pump housing portion, into said head, through said outlet passage, through said one-way valve means through said conduit means, and outwardly through outlet pipe; said pump housing having an annular lower impeller casing portion; an imperforate impeller disc drivingly secured to said motor shaft below said pumping means and within said impeller casing; an annular inlet shroud having a lower continuously smooth internal peripheral wall being rigidly secured below and to said pump housing; a comminuting ring tightly clamped between said pump housing and said inlet shroud; said comminuting ring having an inner annular wall substantially axially aligned with the periphery of said impeller disc; said inner annular wall consisting essentially of a lower continuously smooth wall portion and a second upper comminuting wall portion composed of a plurality of peripherally arranged axial comminuting slots; a plurality of impeller blades on the lower face of said impeller disc extending downwardly and generally radially aligned with said comminuting slots; said comminuting slots extending from a distance substantially below said impeller blades axially upwardly for a distance substantially above said impeller blades; pressure actuated control means for starting and stopping said motor and being contained within said control housing; sealed conduit means extending from said pressure actuated control means downwardly and opening adjacent said inlet shroud, but upwardly from the lower terminal edge of said inlet shroud so that fluid sucked in by said pumping means will have an axial velocity component away from said conduit means opening for preventing clogging; and a fluid vent pipe extending through said control housing portion to provide free air passage from the upper portion of said receptacle to the exterior of said receptacle.

Claim 3

Dependent Claim 144 words

Apparatus for comminuting and pumping semi-fluid material comprising: a tank having an upper open end; cover means releasably and sealingly mounted to the periphery of said upper open end; a plurality of substantially vertical tension bolts extending through said cover means downwardly into said tank for a substantial distance; a comminutor, a pump, and a motor directly driving said comminutor and pump being arranged such that fluid is pumped upwardly through said comminutor from said tank and then through said pump; chamber means extending from said upper open end downwardly into said tank and sealingly containing therein said motor, said motor being mounted upwardly from the lower terminal end of said tension bolts; the terminal lower end of said bolts being secured to said chamber means for carrying the entire weight of said chamber means, motor, pump and comminutor in tension from said cover.

Claim 4

Dependent Claim 144 words

Apparatus for comminuting and pumping semi-fluid material comprising: a tank having an upper open end; cover means releasably and sealingly mounted to the periphery of said upper open end; a plurality of substantially vertical tension bolts extending through said cover means downwardly into said tank for a substantial distance; a comminutor, a pump, and a motor directly driving said comminutor and pump being arranged such that fluid is pumped upwardly through said comminutor from said tank and then through said pump; chamber means extending from said upper open end downwardly into said tank and sealingly containing therein said motor, said motor being mounted upwardly from the lower terminal end of said tension bolts; the terminal lower end of said bolts being secured to said chamber means for carrying the entire weight of said chamber means, motor, pump and comminutor in tension from said cover.

Claim 5

Dependent Claim 31 words

The apparatus of claim 2, including motor means carried in the upper portion of said chamber Means for actuating said motor in response to the level of fluid within said tank.

Claim 6

Dependent Claim 47 words

The apparatus of claim 3, wherein said cover means is annular; and a cover plate being releasably and sealingly mounted within said annular cover means to provide access to said motor controls and together with said annular cover means completely sealing the upper end of said tank.

Claim 7

Dependent Claim 65 words

The apparatus of claim 2, wherein said tank is of a one-piece construction with a bottom wall, a substantially cylindrical side wall, and an outwardly extending upper flange; said cover means being releasably secured to said upper flange; and an inlet pipe sealingly extending through said side wall and having an outer coupling end and a free inner end for discharging directly into said tank.

Claim 8

Dependent Claim 28 words

The apparatus of claim 2, including an outlet pipe sealingly extending through said cover means; and said pump having a discharge directly fluid connected to said outlet pipe.

Claim 9

Dependent Claim 44 words

The apparatus of claim 6, wherein said pump includes a one-piece pump head having said discharge; said outlet pipe being directly secured to said pump head; and including a resilient flapper one-way valve clampingly secured directly between said outlet pipe and said pump head.

Claim 10

Dependent Claim 61 words

The apparatus of claim 2, wherein said pump includes a one-piece pump head forming the lower portion of said chamber means; said motor being mounted directly on the upper end of said pump head and having a shaft extending vertically downwardly through said pump head; and bearing and packing means being operatively mounted between said pump head and said motor shaft.

Claim 11

Dependent Claim 23 words

The apparatus of claim 8, wherein said pump includes an outer one-piece casing being directly releasably secured to and below said pump head.

Claim 12

Dependent Claim 80 words

The apparatus of claim 9, wherein said pump includes a pump impeller secured to the periphery of said motor shaft within said pump casing; and said comminutor including an imperforate impeller disk secured to the terminal lower end of said motor shaft, a comminutor ring operatively surrounding said impeller disk, and a one-piece inlet shroud releasably secured directly to the lower end of said pump casing with said comminutor ring clampingly retained between said inlet shroud and said pumping casing.

Claim 13

Dependent Claim 279 words

A grinder-pump unit comprising: a motor having a vertical axis of rotation; vertically downwardly extending motor drive shaft means; a hollow pump head below said motor and surrounding said motor shaft means; bearing and packing means supportingly and sealingly connected to said shaft means between said pump head hollow interior and said motor; a pump casing extending below and secured directly to said pump head; a comminutor inlet shroud extending below and directly secured to said pump casing; pump means extending between said motor shaft means and said pump casing; comminutor impeller means secured to lower terminal end of said motor shaft means below said pump means; stationarily mounted cooperating comminutor stator means secured between said pump casing and said inlet shroud; said pump head including an annular discharge chamber surrounding said motor shaft means upwardly of said pump means and said pump casing, and an outlet passage radially extending through said pump head above said pump casing into said annular discharge chamber; said pump means being a helical pump having a resilient material relatively fixed portion comprising an outwardly extending mounting flange clampingly secured directly between said pump head and said pump casing, an outer annular wall integrally depending from said mounting flange and extending away from the adjacent surface of said pump casing to a lower terminal end, an inner annular wall portion integrally extending upwardly from said outer annular wall terminal end, said inner annular wall having a helical thread on its internal surface surrounding said motor shaft means; and cooperating helical thread means on said motor shaft means interengaging with said helical thread during rotation of said motor shaFt means to pump fluid upwardly therebetween.

Claim 14

Dependent Claim 279 words

A grinder-pump unit comprising: a motor having a vertical axis of rotation; vertically downwardly extending motor drive shaft means; a hollow pump head below said motor and surrounding said motor shaft means; bearing and packing means supportingly and sealingly connected to said shaft means between said pump head hollow interior and said motor; a pump casing extending below and secured directly to said pump head; a comminutor inlet shroud extending below and directly secured to said pump casing; pump means extending between said motor shaft means and said pump casing; comminutor impeller means secured to lower terminal end of said motor shaft means below said pump means; stationarily mounted cooperating comminutor stator means secured between said pump casing and said inlet shroud; said pump head including an annular discharge chamber surrounding said motor shaft means upwardly of said pump means and said pump casing, and an outlet passage radially extending through said pump head above said pump casing into said annular discharge chamber; said pump means being a helical pump having a resilient material relatively fixed portion comprising an outwardly extending mounting flange clampingly secured directly between said pump head and said pump casing, an outer annular wall integrally depending from said mounting flange and extending away from the adjacent surface of said pump casing to a lower terminal end, an inner annular wall portion integrally extending upwardly from said outer annular wall terminal end, said inner annular wall having a helical thread on its internal surface surrounding said motor shaft means; and cooperating helical thread means on said motor shaft means interengaging with said helical thread during rotation of said motor shaFt means to pump fluid upwardly therebetween.

Claim 15

Dependent Claim 44 words

The apparatus of claim 11, including a discharge pipe directly and releasably secured to said pump head in fluid communication with said outlet passage; and a resilient flapper valve clampingly sealed between said discharge pipe and said pump head for valving said discharge outlet.

Claim 16

Dependent Claim 31 words

The apparatus of claim 11, wherein said pump head is of a one-piece construction, said pump casing is of a one-piece construction and said inlet shroud is of a one-piece construction.

Claim 17

Dependent Claim 90 words

The apparatus of claim 11, wherein said comminutor impeller includes an imperforate impeller disk and at least one impeller blade secured to the lower face of said impeller disk and extending downwardly therefrom with a radially outer terminal end substantially flush with the outer periphery of said impeller disk; and said comminutor stator means is a cutter ring having an internal annular wall consisting essentially of a first lower annular continuously smooth surface and a second annular cutting surface of a plurality of uniformly peripherally spaced identical axially extending slots.

Claim 18

Dependent Claim 68 words

The apparatus of claim 14, wherein said impeller blades are of substantially the same thickness as said impeller disk, as measured in the vertical direction; said axially extending slots extending from below said impeller blades vertically upwardly to terminate above said impeller blades, but below the adjacent upper surface of said impeller disk; said cutter ring internal annular wall being outward of the periphery of said impeller disk.

Claim 19

Dependent Claim 119 words

The apparatus of claim 11, wherein said pump head has an axially extending passage; said pump casing having at its lower end an outwardly facing slot substantially axially aligned with said pump head axially extending passage; a pipe having an upper end threadingly received in said pump head axially extending passage and a lower free end engaging within said pump casing slot; a strap secured at one end to said pump casing on one side of said slot to extend tightly around said pipe to the other side of said slot and having its other end secured to said pump casing; and automatic control means communicating through said pipe for actuating said pump means in response to fluid level.

Claim 20

Dependent Claim 180 words

A comminutor, comprising: a one-piece annular inlet shroud having a free terminal lower end, an upwardly facing annular shoulder, and an annular internal surface extending completely from said terminal lower end to said annular shoulder; a comminutor ring having an internal diameter substantially the same as the internal diameter of said shroud internal surface and resting on said annular shoulder; a substantially annular impeller housing having a downwardly facing annular shoulder substantially aligned with said upwardly facing annular shoulder and being releasably secured to said inlet shroud for clamping therebetween said comminutor ring; a shaft extending through said impeller housing and having drive means at its upper end; a comminutor impeller drivingly secured to the lower terminal end of said shaft within said impeller housing for cooperation with said comminutor ring; said comminutor impeller including an imperforate disc having a peripheral edge closely adjacent to the inner periphery of said comminutor ring; and pump means driven by rotation of said shaft for sucking fluid upwardly through said inlet shroud and only between said imperforate impeller disc and said comminutor ring.

Claim 21

Dependent Claim 180 words

A comminutor, comprising: a one-piece annular inlet shroud having a free terminal lower end, an upwardly facing annular shoulder, and an annular internal surface extending completely from said terminal lower end to said annular shoulder; a comminutor ring having an internal diameter substantially the same as the internal diameter of said shroud internal surface and resting on said annular shoulder; a substantially annular impeller housing having a downwardly facing annular shoulder substantially aligned with said upwardly facing annular shoulder and being releasably secured to said inlet shroud for clamping therebetween said comminutor ring; a shaft extending through said impeller housing and having drive means at its upper end; a comminutor impeller drivingly secured to the lower terminal end of said shaft within said impeller housing for cooperation with said comminutor ring; said comminutor impeller including an imperforate disc having a peripheral edge closely adjacent to the inner periphery of said comminutor ring; and pump means driven by rotation of said shaft for sucking fluid upwardly through said inlet shroud and only between said imperforate impeller disc and said comminutor ring.

Claim 22

Dependent Claim 58 words

The apparatus of claim 17, wherein said inlet shroud annular inlet surface is continuously smooth; and said comminutor ring includes an inner wall consisting essentially of a first continuously smooth annular surface substantially forming a continuation of said inlet shroud internal surface and a second upper cutter surface having a plurality of peripherally uniformly spaced axially extending slots.

Claim 23

Dependent Claim 29 words

The apparatus of claim 18, including at least one impeller blade mounted on the lower surface of said impeller disc and extending dowNwardly in radial opposition with said slots.

Claim 24

Dependent Claim 194 words

A comminutor, comprising: a one-piece annular inlet shroud having a free terminal lower end, an upwardly facing annular shoulder, and a continuously smooth annular internal surface extending completely from said terminal lower end to said annular shoulder; a comminutor ring having an internal diameter substantially the same as the internal diameter of said shroud internal surface and resting on said annular shoulder; a substantially annular impeller housing having a downwardly facing annular shoulder substantially aligned with said upwardly facing annular shoulder and being releasably secured to said inlet shroud for clamping therebetween said comminutor ring; a shaft extending through said impeller housing and having drive means at its upper end; a comminutor impeller drivingly secured to the lower terminal end of said shaft within said impeller housing for cooperation with said comminutor ring; said inlet shroud and said comminutor ring having their internal annular surfaces substantially axially aligned in the vertical direction; and the internal surface of said inlet shroud flaring slightly radially outward from said shoulder to its terminal lower end, and the internal surface of said comminuting ring consisting of a first lower continuously smooth annular surface and a second upper bladed

Claim 25

Dependent Claim 194 words

A comminutor, comprising: a one-piece annular inlet shroud having a free terminal lower end, an upwardly facing annular shoulder, and a continuously smooth annular internal surface extending completely from said terminal lower end to said annular shoulder; a comminutor ring having an internal diameter substantially the same as the internal diameter of said shroud internal surface and resting on said annular shoulder; a substantially annular impeller housing having a downwardly facing annular shoulder substantially aligned with said upwardly facing annular shoulder and being releasably secured to said inlet shroud for clamping therebetween said comminutor ring; a shaft extending through said impeller housing and having drive means at its upper end; a comminutor impeller drivingly secured to the lower terminal end of said shaft within said impeller housing for cooperation with said comminutor ring; said inlet shroud and said comminutor ring having their internal annular surfaces substantially axially aligned in the vertical direction; and the internal surface of said inlet shroud flaring slightly radially outward from said shoulder to its terminal lower end, and the internal surface of said comminuting ring consisting of a first lower continuously smooth annular surface and a second upper bladed

Claim 26

Dependent Claim 109 words

A sewage installation, comprising a closed tank having an upper removable cover and an inlet pipe below said cover for discharging sewage directly into said tank; a sewage grinding and pumping unit supportingly mounted only on and depending from said unit having housing means forming a substantially sealed chamber with respect to the inside of said tank; motor and motor control means mounted within said sealed chamber; a downwardly opening comminutor and upper pump mounted externally from and below said housing means; and said cover including a first annular portion rigidly supporting said unit and a second cover mounted for removal to expose the interior of said sealed chamber.

Claim 27

Dependent Claim 109 words

A sewage installation, comprising a closed tank having an upper removable cover and an inlet pipe below said cover for discharging sewage directly into said tank; a sewage grinding and pumping unit supportingly mounted only on and depending from said unit having housing means forming a substantially sealed chamber with respect to the inside of said tank; motor and motor control means mounted within said sealed chamber; a downwardly opening comminutor and upper pump mounted externally from and below said housing means; and said cover including a first annular portion rigidly supporting said unit and a second cover mounted for removal to expose the interior of said sealed chamber.

Claim 28

Dependent Claim 29 words

The apparatus of claim 21, wherein said pump has a discharge side; and including a discharge pipe extending from the discharge side of said pump upwardly through said cover.

Claim 29

Dependent Claim 41 words

The apparatus of claim 21, wherein said tank and housing means include a free sewage area below said unit and annularly surrounding said unit from the bottom of said tank continuously upwardly the full length of said unit to said cover.

Claim 30

Dependent Claim 30 words

The apparatus of claim 21, wherein said motor includes a motor shaft extending through said housing means and having mounted directly thereon a pump impeller and a lower comminuting impeller.

Claim 31

Dependent Claim 139 words

A sewage installation, comprising a closed tank having an upper removable cover and an inlet pipe below said cover for discharging sewage directly into said tank; a sewage grinding and pumping unit supportingly mounted only on and depending from said cover entirely within said tank; said unit having housing means forming a substantially sealed chamber with respect to the inside of said tank; motor and motor control means mounted within said sealed chamber; a downwardly opening comminutor and upper pump mounted externally from and below said housing means; said housing means including a one-piece control housing integral with said cover and having therein said motor control means; said housing means further including a tube telescopically engaging said control housing and depending therefrom; and said housing means further including a pump head telescopically engaging the lower end of said tube.

Claim 32

Dependent Claim 139 words

A sewage installation, comprising a closed tank having an upper removable cover and an inlet pipe below said cover for discharging sewage directly into said tank; a sewage grinding and pumping unit supportingly mounted only on and depending from said cover entirely within said tank; said unit having housing means forming a substantially sealed chamber with respect to the inside of said tank; motor and motor control means mounted within said sealed chamber; a downwardly opening comminutor and upper pump mounted externally from and below said housing means; said housing means including a one-piece control housing integral with said cover and having therein said motor control means; said housing means further including a tube telescopically engaging said control housing and depending therefrom; and said housing means further including a pump head telescopically engaging the lower end of said tube.

Claim 33

Dependent Claim 34 words

The apparatus of claim 25, including sealing means at each of said telescopic connections and means extending between and tightly clamping said pump head and said control housing together axially with said tube interposed.

Claim 34

Dependent Claim 212 words

A sewage installation, comprising a closed tank having an upper removable cover and an inlet pipe below said cover for discharging sewage directly into said tank; a sewage grinding and pumping unit supportingly mountEd only on and depending from said cover entirely within said tank; said unit having housing means forming a substantially sealed chamber with respect to the inside of said tank; motor and motor control means mounted within said sealed chamber; a downwardly opening comminutor and upper pump mounted externally from and below said housing means; said comminutor including a stationary comminuting ring and a rotatably mounted impeller disc within said ring; said pump being operable to pump fluid upwardly between said impeller disc and said comminuting ring; said impeller disc being imperforate to pumped fluid and having at least two diametrically opposed downwardly extending impeller blades; each of said impeller blades having an outer edge substantially axially flush with the outer periphery of the impeller disc; said impeller disc having a lowermost at least annular planar surface extending substantially to its outer periphery and being perpendicular to the axis of rotation; each of said impeller blades having a height, as measured in the axial direction, beyond said impeller disc planar surface within the range of 0.200 - 0.250 inch.

Claim 35

Dependent Claim 212 words

A sewage installation, comprising a closed tank having an upper removable cover and an inlet pipe below said cover for discharging sewage directly into said tank; a sewage grinding and pumping unit supportingly mountEd only on and depending from said cover entirely within said tank; said unit having housing means forming a substantially sealed chamber with respect to the inside of said tank; motor and motor control means mounted within said sealed chamber; a downwardly opening comminutor and upper pump mounted externally from and below said housing means; said comminutor including a stationary comminuting ring and a rotatably mounted impeller disc within said ring; said pump being operable to pump fluid upwardly between said impeller disc and said comminuting ring; said impeller disc being imperforate to pumped fluid and having at least two diametrically opposed downwardly extending impeller blades; each of said impeller blades having an outer edge substantially axially flush with the outer periphery of the impeller disc; said impeller disc having a lowermost at least annular planar surface extending substantially to its outer periphery and being perpendicular to the axis of rotation; each of said impeller blades having a height, as measured in the axial direction, beyond said impeller disc planar surface within the range of 0.200 - 0.250 inch.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1975-06-06	1975-12-06	1976-06-06	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1979-06-06	1979-12-06	1980-06-06	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1983-06-06	1983-12-06	1984-06-06	$7700.00	Window Closed / Lapsed

Pump storage grinder

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