March 24, 1970
`
`a. S. BUKEWIHGE ET AL
`CLOSE-COUPLED CENTRIFUGAL PUMP
`
`3,502,030
`
`Filed May s. 1968 /OB
`
`I .
`I
`
`.
`
`"~.
`
`J s
`
`84-
`
`BEN ..S: Bt/~EW/HGE,
`HAROLD A. CLA.<?NO,J.e.
`INVENTORS
`
`ATTORNC'J&
`
`PAGE 1 OF 8
`
`PETITIONERS' EXHIBIT 1125
`
`

`

`March 24, 1970
`
`B. S. BUKEWIHGE ET AL
`CLOSE-COUPLED CENTRIFUGAL PUMP
`
`Filed May 8, 1968
`
`/04---,--------
`
`3,502,030
`
`4 Sheets-Sheet 2
`
`24
`
`~G-.7.
`
`BEN J. 8t/REW/#GC,
`#AROLO A. CL4RIVO, J.e.
`INVENTOIU
`
`PAGE 2 OF 8
`
`

`

`March 24, 1970
`
`Filed May 8, 1968
`
`8. S. BUKEWIHGE gT AL
`CLOSE-COUPLED CENTRIFUGAL PUMP
`
`3,502,030.
`
`4 Sheets-Sheet ~
`
`r-·pl;l/2
`
`l.-,-- _ _j
`/08./
`
`78
`
`BEN .S: Bt/-e'EW/14/GE.
`#4ROL£> A. CLARM?, J,e.
`JNVENTURJ
`
`PAGE 3 OF 8
`
`

`

`March 24, 1970
`
`Filed May 8, 1968
`
`B. S. BUKEWIHGE ET AL
`CLOSE-COUPLED CENTRIFUGAL PUMP
`
`3,502,030
`
`4 Sheets-Sheet 4
`
`30
`
`52
`
`BEN S. Bt/At'EW/NGE.,
`NAROLO A. CLARNO, JR.
`iNVENTORS
`
`PAGE 4 OF 8
`
`

`

`United States Patent Office
`
`3,502,030
`Patented Mar. 24, 1970
`
`5
`
`10
`
`2
`thermosetting resin which is loaded with metallic par(cid:173)
`ticles. The proportion of metallic particles to resin is
`such that the particles are isolated from one another
`by a matrix of resin so that the coating is not electrical-
`ly conductive. The metallic particles are, however,
`present in sufficient quantity to increase the thermal
`conductivity of the coating to a level where it will con(cid:173)
`duct away a sufficient amount of heat to permit the
`motor to operate continuously.
`The stationary volute casing is releasably sealed to
`the pump side of the mounting plate. The rating of the
`pump may be changed as desired by removing the
`stationary volute casing and its matched impeller from
`the pump side of the mounting plate and replacing them
`15 with a casing and impeller of different characteristics.
`In the drawings:
`FIG. 1 is a perspective view of the close-coupled,
`water immersible centrifugal pump of this invention;
`FIG. 2 is a side elevation of the pump shown in
`20 FIG. 1;
`FIG. 3 is a side elevation partially in cross section
`and in phantom lines of the pump shown in FIG. 1;
`FIG. 4 is a planned view partially in cross section
`and in phantom of the pump shown in FIG. 1;
`FIG. 5 is a cross-sectional view taken along lines
`5-5 in FIG. 4;
`FIG. 6 is a cross-sectional view taken along line 6-6
`in FIG. 5;
`FIG. 7 is a cross-sectional view of an impeller taken
`30 along line 7-7 in FIG. 6;
`FIG. ·8 is a cross-sectional view taken along line 8-8
`in FIG. 5;
`FIG. 9 is a partial cross-sectional view taken along
`line 9-9 in FIG. 8;
`FIG. 10 is an exploded perspective view of the pump
`shown in FIG. 1;
`FIG. 11 is a partial cross-sectional view of an addi(cid:173)
`tional embodiment of a shaft seal; and
`FIG. 12 is a partial cross-sectional view of a further
`embodiment of a shaft seal.
`· With particular reference to FIGS. 5 and 10 there
`is illustrated a single stage, single suction centrifugal
`pump 10, a mounting plate 12, a stationary volute cas-
`45 ing 18, an impeller 30, a shaft 32, a bearing bracket
`40, a shaft seal 42, self-centering bearings 58 and 88,
`a shaded pole induction motor 76, and rotor bearing
`support 84 operatively associated with one another as
`is described and shown more particularly hereinafter.
`50 Mounting plate 12 is provided with first side 14 and
`second side 16. A stationary volute casing 18 is mounted
`in fluid tight relationship to first side 14 of mounting plate
`12. Stationary volute casing 18 is provided with suction
`port 20 and discharge port 22. A casing seal 24 is posi-
`55 tioned between casing 18 and first side 14. Casing 18 is
`fastened to first side 14 by means of mounting screws 26,
`only one which is shown. The interior wall of casing 18
`defines involute shaped impeller cavity 28. The involute
`shape of this cavity is emphasized by the dash circle
`60 drawn on the same center and shown in FIG. 6. Impel(cid:173)
`ler 30 is shown particularly in FIGS. 5, 6, 7, and 10.
`The direction of rotation of impeller 30 is indicated
`by the arrow in FIG. 6. Impeller 30 is mounted on the
`first end 34 of shaft 32. First end 34 is splined as shown
`in FIG. 7. The second end of shaft 32 is indicated at 36.
`An opening 38 is provided in mounting plate 12 to re(cid:173)
`ceive shaft seal 42. Bearing bracket 40 is adapted to hold
`shaft seal 42 and the self-centering bearing 58. Bearing
`bracket 40 is attached to mounting plate 12 by means
`70 of mounting screws 41, only one of wh'ch is shown.
`Shaft seal 42, as shown particularly in FIGS. 5, 8, and
`10, includes an annular seal plate 44 which is provided
`
`1
`
`3,502,030
`CLOSE-COUPLED CENTRIFUGAL PUMP
`Ben S. Bukewihge, 2810 W. 232nd St., Torrance, Calif.
`90505, and Harold A. Clarno, Jr., 235 Alster Ave.,
`Arcadia, Calif. 91006
`Filed May 8, 1968, Ser. No. 727,520
`Int. CI. F04d 13/06; F16c 1/24
`U.S. 'Ci. 103-87
`
`8 Claims
`
`ABSTRACT OF THE DISCLOSURE
`A close-coupled centrifugal pump which includes a
`mounting plate having a centrifugal pump casing re(cid:173)
`leasably sealed to the pump side of the plate and a
`motor encapsulated on the other side of the plate, and
`one of a plurality of fluid tight shaft seals preventing
`the passage of fluid from the pump side to the motor
`side of the mounting plate.
`
`According to this invention, a close-coupled, immersi(cid:173)
`ble centrifugal pump is provided; and more particularly,
`a small sealed, close-coupled centrifugal pump is pro(cid:173)
`vided which is capable of being immersed in the liquid
`which is being pumped.
`Considerable difficulty had previously been experienced
`in providing low maintenance, sealed centrifugal pumps
`of small proportions and with motors of fractional
`horsepowers. Also, the adaptability of previous pumps
`to different service conditions was severely restricted.
`These and other disadvantages of the prior art have
`been overcome, according to the present invention, by
`the provision of a close-coupled centrifugal pump which
`comprises a mounting plate having a pump side and a
`motor side. A stationary volute casing is releasably sealed
`to the pump side of the mounting plate, and an impeller
`is mounted in the casing on a rotatable ·shaft. The shaft
`passes through a shaft seal at the mounting plate and
`extends on into a motor which is mounted adjacent
`to the motor side of the mounting plate. The rotor
`of the motor is mounted on the shaft. The shaft is
`journaled in bearings positioned on either side of the
`rotor. The rotor, the shaft, and the bearings are en(cid:173)
`closed in a container which is impervious to viscous
`fluids. The motor and bearings are permanently en(cid:173)
`capsulated in an electrically nonconductive, thermally
`conductive, solidified in situ coating.
`The shaft seal, which is mounted in sealing relation(cid:173)
`ship with the mounting plate to prevent the passage
`of fluid along the shaft from the pump side to the motor
`side of the mounting plate, is selected from one of a
`plurality of available seals depending upon the service
`conditions to which the close-coupled pump will be sub(cid:173)
`jected.
`The shaft in the close-coupled centrifugal pump of
`this invention is mounted in self-centering bearings which
`are permanently lubricated by lubricant-saturated pads
`surrounding the self-centering bearings. The shaft seals are
`of such construction that they require no maintenance.
`The motor and the bearings are permanently encapsu(cid:173)
`lated in an encapsulating agent which is cast in a fluid
`state and solidifies in situ to a hard coating. The motor
`and bearings are enclosed so that the viscous encapsulat(cid:173)
`ing agent does not penetrate into the bearings or into
`the space in which the rotor operates. The close-coupled
`pump is generally so arranged that everything on the
`motor side of the mounting plate is encapsulated along
`with the motor side of the mounting plate. The en(cid:173)
`capsulation is permanent, and the encapsulated unit may
`be immersed in an electrically conductive fluid while it
`is operating. The encapsulating agent is generally a
`
`25
`
`35
`
`40
`
`65
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`PAGE 5 OF 8
`
`

`

`3,502,030
`
`25
`
`35
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`3
`with a centrally located upset sealing ring 45 which pro(cid:173)
`jects angularly towards and is biased into frictional en(cid:173)
`gagement with shaft 32. Sealing ring 45 projects into
`the opening 38 from the plane plate 44. Seal plate 44 is
`constructed of a material which is resiliently deforma- 5
`ble. The hole through which shaft 32 passes -is of small-
`er diameter than the outside diameter of shaft 32 so that
`the sealing ring 45 is continuously biased into contact
`with shaft 32 by reason of its plastic memory, which
`tries to return plate 44 to a flat configuration. Rigid 10
`washer 46 is pressed against the motor side of seal plate
`44. The inside diameter of rigid washer 46 is greater
`than the outside diameter of shaft 32 so that there is
`no contact between the two. Rigid washer 46 is provided
`with a conical depression at its center. Porous wick 15
`washer 48 is positioned in the central conical depression
`in rigid washer 46. Porous wick washer 48 is in physical
`contact with shaft 32. Washer 48 is loaded with a liquid
`lubricating agent. This liquid lubricating agent lubricates
`shaft seal 42. This lubricating agent also serves to ernul- 20
`sify any water which may pass from the pump side to
`the motor side of seal plate 44. The outer peripheries of
`seal plate 44 and rigid washer 46 are sealed with suitable
`sealant so as to prevent the passage of liquid along these
`peripheries.
`A further embodiment of the shaft seal of this inven(cid:173)
`tion is shown particularly in FIG. 11. Shaft seal 50 is
`a dual lip seal which is provided with a rigid disc 52
`having a flexible angularly projecting shaft engaging lip
`54 which is in frictional engagement with shaft 32 and 30
`is biased towards shaft 32. A flexible conical membrane
`56 projects angularly toward the second end of shaft
`32 in the generally opposite direction from lip 54. Mem(cid:173)
`brane 56 is in frictional engagement with and is biased
`towards shaft 32.
`Self-centering bearings 58 and 88, shown particularly
`in FIGS. 5 and 11, include respectively, porous metallic
`sleeve bearings 60 and 90 which serve to lubricate and
`journal shaft 32. Bearings 60 and 90 are mounted in
`bearing cages which permit some movement of these 40
`bearings so as to accomplish exact axial alignment be(cid:173)
`tween these bearings and shaft 32. Metallic sleeve bear(cid:173)
`ings 60 and 90 are provided, respectively, with surfaces
`of revolution 62 and 92. Bearing bracket 40 and rotor
`bearing support 84, respectively, are provided with mat- 45
`ing surfaces of revolution 64 and 94. These surfaces of
`revolution are designed to permit limited movement of
`the metallic sleeve bearings so as to permit axial align(cid:173)
`ment of these bearings with shaft 32. Bearings 58 and
`88, respectively, are provided with bearing support plates 50
`,66 and 96 which are positioned at the ends of the metal-
`lic sleeve bearings which are opposite from the mating
`surfaces of revolution. Bearing support plates 66 and 96
`are provided, respectively, with bearing retainer rings
`68 a.11d 98. These bearing retainer rings are in movable, 55
`frictional engagement with the respective metallic sleeve
`bearings. These bearing retainer rings permit movement
`of the metallic sleeve bearings but provide more resist(cid:173)
`ance to such movement than do the surfaces of revolu(cid:173)
`tion at the opposite ends of the respective metallic sleeve 60
`bearings. Bearing retainer rings 68 and 98, respectively,
`rest on and are pressed against porous deformable pack(cid:173)
`ings 70 and 100. Packings 70 and 100 are loaded with
`a lubricant which seeps through the porous sleeve bear-
`ings to provide lubrication between shaft 32 and the re(cid:173)
`spective bearing surfaces. The position of retainer rings
`68 and 98, respectively, may be shifted slightly against
`the deformable packings to facilitate alignment of the
`sleeve bearings and shaft 32. Self-centering bearings 58 70
`and 88, respectively, are held together by bearing re(cid:173)
`tainer plates 72 and 102 which are secured in bearing
`bracket 40 and rotor bearing support 84, respectively.
`These retainer plates are spaced slightly from retainer
`rings 68 and 98 respectively, by suitable compression 75
`
`65
`
`means which bear against the retainer rings to force them
`against the deformable packings.
`A first spacer 74 is positioned around shaft 32 between
`bearing 58 and rotor 78, and second spacer 75 is posi(cid:173)
`tioned around shaft 32 between bearing 88 and rotor
`78.
`Shaded pole induction motor 76 includes rotor 78
`which is mounted on shaft 32, stator 80, and field wind(cid:173)
`ing 82 which is wound on a leg of stator 80. Stator SO
`is composed of flat plates secured together with a round
`opening for the rotor cut perpendicularly through this
`stack of metal plates. Induction motor 76 is mounted to
`bearing bracket 40 by means of mounting bolts 81 and
`mounting nuts and washers 83 (only one of which is
`shown). Rotor bearing support 84 encloses one end of
`rotor 78 and also provides a mounting support for bear-
`ing 88. Rotor bearing support 84 is attached to stator
`80 and bearing bracket 40 by means of mounting screws
`86 (only one mounting screw is shown) which pass
`through stator 80 and are threadably received in bear(cid:173)
`ing bracket 40. Bearing bracket 40, stator 80, and rotor
`bearing support 84 form a compartment in which rotor
`78 is housed. This compartment is fluid tight insofar as
`viscous fluids are concerned.
`All of the elements on the second side of mounting
`plate 12 are permanently encapsulated within a coating
`104 of electrically insulative, thermally conductive mate(cid:173)
`rial which is cast around these elements and solidified
`in situ. The compartment containing rotor 78 is suffi(cid:173)
`ciently fluid tight to prevent the viscous encapsulating
`agent from leaking into this compartment before it solidi-
`fies. In order to facilitate the transfer of heat from the
`vicinity of the rotor 78 and to suppport the pump, fins
`106 (FIG. 2) are provided in the solidified in situ coat-
`ing 104. Electrical current is provided for the operation
`of motor 76 by means of a three-wire electrical cord
`108. Insulated cord 108 is liquid impervious, and its ex(cid:173)
`posed ends are encapsulated in coating 104. Mounting
`plate 12 is provided with mounting brackets 110 by
`means of which the close-coupled centrifugal pump may
`be mounted to a suitable base, as shown particularly in
`FIG. 1. An ear 112, FIGS. 8 and 9, is provided on mount(cid:173)
`ing plate 12 which is adapted to receive electrical cord
`lOS and retain it in the desired position during the en(cid:173)
`capsulating procedure. A retainer 114 is secured around
`electrical cord lOS and is spaced from ear 112 to prevent
`cord lOS from being loosened in or pulled out of coat(cid:173)
`ing 104. In addition to locking cord lOS in coating 104,
`the collar on retainer 114 prevents liquid from entering
`coating 104 along cord 108.
`Referring particularly to FIG. 12, there is illustrated
`a mechanical seal in which snap ring 116 is snapped onto
`shaft 32. A rubber cushion 11S is positioned adjacent to
`snap ring 116 and in contact with shaft 32. Snap ring
`116 and rubber cushion 11S rotate with shaft 32. Float(cid:173)
`ing seat 120 is positioned axially adjacent to rubber
`cushion US. Floating seat 120 rotates with shaft 32 and
`is provided with rotating mating surface 121. Mating sur(cid:173)
`face 121 is in frictional and sealing engagement with
`stationary mating surface 123 of carbon seal ring 122.
`Carbon seal ring 122 is contained in spring adapter 124.
`Spring adapter 124 is urged forward, carrying carbon
`seal ring 122 with it, by spring 126. Spring 126 is con(cid:173)
`fined between spring adapter 124 and case 130. Inside
`case 12S serves to prevent the spring 126 from forcing
`spring adapter 124 completely out of case 130 while
`the mechanical seal is being assembled before carbon
`seal ring 122 is in contact with floating seat 120. Float(cid:173)
`ing seat 120 and case 130 are spaced concentrically with,
`but out of contact with, shaft 32. The passage of fluid
`along the interior of case 130, between the inner wall
`of case 130 and the inner diameter of carbon seal ring
`122, is prevented by the presence of 0-ring 132. This
`mechanical seal is confined within opening 3S of mount(cid:173)
`ing plate 12. This mechanical seal is particularly adapted
`
`PAGE 6 OF 8
`
`

`

`3,502,030
`
`65
`
`5
`for use where the liquid which is being pumped on the
`pump side 14 of mounting plate 12 contains abrasives or
`is of a corrosive nature.
`The coating 104 is, for example, a thermosetting com(cid:173)
`position composed of eight fluid ounces of rigid polyester
`resin, two fluid ounces of fine mesh granular aluminum
`powder, and four fluid ounces of powdered limestone,
`three fluid ounces of milled fiberglas, catalyzed by methyl
`ethyl ketone peroxide. The resin waterproofs the coat(cid:173)
`ing and surrounds the aluminum particles to insulate
`them electrically from each other. The aluminum particles
`are in sufficiently close proximity to one another to allow
`heat to be transferred from one aluminum particle to
`another to effect rapid dissipation of deleterious heat.
`The limestone and fiberglass act as a binder which in(cid:173)
`crease the thermal stability and impact resistance of the
`coating 104.
`The elements on the second side 16 of mounting plate
`12 are provided with mating surfaces which facilitate the
`accurate alignment of the components when the close(cid:173)
`coupled centrifugal pump 10 is assembled. An annular
`lip on bearing bracket 40 fits over the boss which sur(cid:173)
`rounds and defines opening 38 on second side 16 of mount-
`ing plate 12 so as to provide accurate concentric align(cid:173)
`ment between opening 38 and bearing bracket 40. The
`bosses on bearing bracket 40 which receive the mounting
`screws 41 which secure plate 12 to bearing bracket 40
`are spaced radially outwardly some distance from the
`axis of self-centering bearing 58. These bosses which
`receive screws 41 bear directly against the second side 16
`of mounting plate 12 so as to further insure accurate axial
`alignment between opening 38 and bearing bracket 40.
`The mating surfaces between laminated stator 80 and
`bearing bracket 40 are distributed over a large area and
`bear against one another so as to insure concentric and
`axial alignment of the opening in stator 80 with the axis
`of bearing bracket 40. The mating surfaces between stator
`80 and rotor bearing support 88 are distributed over a
`sufficiently broad area to enable the accurate and stable,
`concentric and axial alignment of rotor bearing support
`84 with the opening in stator 80. Since each of the ele(cid:173)
`ments on second side 16 of mounting plate 12 is accurately
`aligned with and securely fixed to its adjacent elements,
`all of these elements are in accurate concentrical and axial
`alignment with opening 38.
`The bearing bracket 40 and rotor bearing support 84
`are provided with relatively large openings to accom(cid:173)
`modate pacldngs 70 and 100, respectively. These packings
`serve as reservoirs for the liquid lubricant which lubricates
`the bearings in which shaft 32 is mounted. The large size 50
`of these packings, which may conveniently be felt pads,
`insures a sufficient supply of lubricant throughout the
`life of the close-coupled pump.
`During the manufacturing process, the rotor 78, wind-
`ing 82, and stator 80 are preferably coated with varnish 55
`or other moisture proof material and oven-baked to mois(cid:173)
`ture proof these components. The coil on stator 80 is
`impregnated· under vacuum with varnish. The bearing
`bracket 40 and rotor bearing support 84 are of a moisture
`proof material, such as brass, plastic, zinc, aluminum, 60
`alloy, or the like, which is treated, for example, by
`anodizing or dichromate to inhibit corrosion and moisture
`proof these elements. This treatment, which is preferred,
`enhances the inertness of these components to the en(cid:173)
`capsulating material while it is in the viscous liquid
`state and also serves as added protection in the event that
`the coating 104 partially or completely fails while the
`close-coupled pump is in service. Also, if the seal fails
`and water enters the rotor cavity, the pump will continue
`to operate because the coil and electrical contacts are 70
`electrically insulated from the rotor cavity by the water(cid:173)
`proofing.
`The opening 38 in mounting plate 12 is of such pro(cid:173)
`portions that it is adapted to receive one of a plurality
`of seals. The proper seal is selected for the service con- 75
`
`6
`ditions under which the pump will be operated. For dean
`liquids, which contain little or no grit, seals, such as shown
`in FIG. 11 and FIG. 5, are very effective. Where the
`liquid to be pumped contains abrasive or corrosive mate-
`5 rials, the mechanical seal, shown in FIG. 12, is generally
`preferred.
`Impeller 30 is concentric to and rotates with shaft 32.
`The vanes -on impeller 30 are arranged in a spiral design
`with an open space at the center of the impeller. The
`10 open space permits unimpaired entry of the fluid at the
`center of the impeller. The cuved vanes pick up the fluid
`from the center of the impeller and spin it outwardly
`under the urging of centrifugal force. The spiral arrange"
`ment of the vanes provides a greater radial thrust to
`15 the liquid than would be accomplished through the use
`of straight vanes. Also, the spiral configuration of the
`vanes allows the liquid to slide off of the vanes with
`greater ease than would be the case with straight vanes.
`This ease of stripping the liquid from the vanes reduces
`20 the resistance of the impellers to rotation which permits
`the impeller to maintain a greater velocity with a mini(cid:173)
`mum of power. Suction port 20 is provided immediately
`above and concentrically with impeller 30·. The suction
`port 20 is of substantially larger diameter than discharge
`25 port 22, and the inner walls of suction port 20 are smooth
`and faifl!d into the top of the volute casing 18, thus in(cid:173)
`suring an adequate supply of liquid to the open central
`portion of the impeller 30 with a minimum of turbulence.
`The inner walls and top of the impeller cavity 28 are
`30 smooth and radiused ·to follow the contour of the im(cid:173)
`peller vane profile so as to maintain constant pressures
`wihout undue turbulence.
`The ribs (FIG. 8) on the second side 16 of mounting
`plate 12 provide rigidity to mounting plate 12 and insure
`35 that second side 16 is encapsulated so that no liquid can
`travel between coating 104 and second side 16.
`In addition to a variety of interchangeable shaft seals,
`impellers and casings which may be employed according
`to this invention, it is possible to change the horsepower
`40 rating of the motor by increasing or decreasing the
`thickness of the stator 80. The horsepower of the motor is
`increased by increasing the thickness of the stator 80.
`As will be understood by those skilled in the art, what
`has been described are preferred embodiments in which
`modifications and changes may be made without depart-
`45 ing from the spirit and scope of the accompanying claims.
`What is claimed is:
`1. A close-coupled centrifugal pump comprising:
`a mounting plate having a pump side and a motor side,
`stationary volute casing having a releasably sealed
`connection to said pump side, an impeller mounted
`in said casing on a rotatable shaft, a shaft seal
`adjacent said plate having an aperture therethrough,
`a portion of said shaft extending through said aper-
`ture, said shaft seal comprising a resiliently deform(cid:173)
`able seal plate having an upset centrally located
`sealing ring which is biased into frictional engage(cid:173)
`ment with said shaft, said seal plate being sealed to
`said mounting plate, said shaft seal being lubricated
`by a porous wick washer which is loaded with a
`lubricant and is positioned in contact with said shaft
`adjacent the motor side of said seal, a motor mounted
`adjacent said motor side having a rotor therein
`mounted on said shaft, bearings on opposite sides of
`said rotor and forming journals for said shaft, a vis(cid:173)
`cous fluid tight container comprising an enclosure
`for said rotor, said shaft and said bearings, and a
`permanent electrically nonconductive, thermally con·
`ductive solidified in situ coating forming an encapsu(cid:173)
`lating encasement for said motor.
`2. The pump of claim 1 wherein said self-centering
`bearings comprise a porous metallic sleeve bearing mova(cid:173)
`bly mounted in a bearing cage, said porous bearing being
`in contact with a lubricant loaded washer.
`3. A close-coupled centrifugal pump comprising:
`
`PAGE 7 OF 8
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`

`

`3,502,030
`
`5
`
`8
`eratively associated with said mounting plate to pre(cid:173)
`vent the passage of fluid from said first side to said
`second side of said mounting plate;
`an impeller attached to said shaft in said impeller
`cavity; and
`said motor being permanently encapsulated in a solidi(cid:173)
`in situ, electrically nonconductive, thermally
`fied
`conductive, thermoset coating of thermosetting resin
`loaded with metallic particles, said coating being in
`direct contact with said container.
`7. The pump of claim 6 wherein the volute casing and
`the impeller are selected from a plurality of casings and
`impellers.
`8. A close-coupled centrifugal pump comprising:
`a mounting plate having a pump side and a motor side;
`a volute casing having an impeller cavity, said casing
`being releasably sealed to said pump side;
`an impeller mounted in said cavity on one end of a ro(cid:173)
`tatable shaft, said shaft extending through said
`mo1,1nting plate;
`a shaft seal around said shaft, said seal preventing the
`passage of liquid from said pump side to said motor
`side of said mounting plate;
`a plurality of elements on said motor side of said plate
`comprising:
`a bearing bracket mounted on the motor side of said
`plate, said bracket containing a first self -centering
`bearing in which said shaft is journaled;
`a stator mounted on said bracket;
`a rotor bearing support mounted on said stator;
`a second self-centering bearing mounted in said rotor
`bearing support, the other end of said shaft being
`journaled in said second bearing;
`a rotor mounted on said shaft in operative association
`with said stator within a viscous fluid tight container
`defined by the combination of said bearing bracket,
`stator and rotor bearing support; and
`said plurality of elements on said motor side being
`waterproofed and permanently encapsulated in ari
`thermally conductive,
`electrically nonconductive,
`solidified in situ coating of thermosetting resin loaded
`with metallic particles, said coating being in direct
`contact with exteriors of each of said bearing bracket,
`stator and rotor bearing support.
`
`7
`a mounting plate having a pump side and a motor side,
`a stationary volute casing having an impeller cavity
`therein, an impeller, a rototable shaft, a bearing
`bracket, a stator, a rotor and a rotor bearing support,
`said shaft havng one end positioned in said cavity,
`said impeller being mounted on said one end, said
`shaft passing through said plate, a shaft seal pre(cid:173)
`venting the passage of fluid from the pump side to
`the motor side of said plate, said shaft extending
`from said shaft seal through and being journaled in a 10
`first self -centering bearing mounted in said bearing
`bracket, said shaft extending from said first bearing
`through a viscous fluid tight container into a second
`self-centering bearing mounted in said rotor bearing
`support, said rotor being mounted on said shaft in 15
`said fluid tight container between said first and sec(cid:173)
`ond bearings, said stator carrying a winding and
`being positioned adjacent said rotor, and an electri(cid:173)
`cally nonconductive, thermally conductive, solidified
`in situ coating of thermosetting resin loaded with 20
`metallic particles permanently encapsulating and
`being in direct contact with said motor side, bearing
`bracket; stator, winding, and rotor bearing support.
`4. A close-coupled centrifugal pump comprising:
`a mounting plate having a pump side, a motor side, 25
`and an opening passing through said plate;
`a centrifugal pump assembly releasably sealed to said
`pump side;
`a motor mounted adjacent the motor side of said plate,
`said motor and said motor side of said plate being 30
`in direct contact with and permanently encapsulated
`in an electrically nonconductive, thermally conduc(cid:173)
`tive, solidified in situ coating of thermosetting resin
`loaded with metallic particles;
`a rotatably mounted shaft extending· from said cen- 35
`trifugal pump through said opening to said motor,
`whereby said motor drives said pump; and
`a shaft seal mounted in sealing relatiomhip with said
`opening in said mounting plate, said shaft extending
`through said seal.
`S. The centrifugal pump of claim 4 wherein said open(cid:173)
`ing is adapted to receive and mount one of a plurality of
`shaft seals.
`6. A close-coupled centrifugal pump comprising:
`a mounting plate having a first side and a second side; 45
`a stationary volute casing mounted in a fluid tight rela-
`tionship to said first side, the interior walls of said
`casing defining an involute shaped impeller cavity;
`a motor mounted adjacent said second side, the rotor of
`said motor being rotatably mounted within a viscous 50
`fluid tight container;
`a shaft extending through said mounting plate from
`said motor into said impeller cavity, said shaft pass(cid:173)
`ing through a shaft seal, said shaft seal being op- 55 310-172
`
`40
`
`References Cited
`UNITED STATES PATENTS
`1/1964 Zimmermann.
`2/1965 Johnson.
`
`3,117;526
`3,170,407
`
`ROBERT M. WALKER, Primary Examiner
`
`U.S. Cl. X.R.
`
`PAGE 8 OF 8
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