US2218003A

US2218003A - Submersible pump motor

Info

Publication number: US2218003A
Application number: US127674A
Authority: US
Inventors: Jr John B Hawley
Original assignee: Reconstruction Finance Corp
Current assignee: Reconstruction Finance Corp
Priority date: 1937-02-25
Filing date: 1937-02-25
Publication date: 1940-10-15
Anticipated expiration: 1957-10-15

Description

Oct. 15, 1940. )l B HAWLEY' JR 2,218,003

SUBMERSIBLE PUMP MOTOR Filed Feb. 25, 1937 2 Shea-@ Shee l J. B. HAWLEY, JR

SUBMERSIBLE PUMP MOTOR Filed Feb. 25, 193'? lll n /7 la wy @mf hf .WH MZ M ai 0000000000 OOOOUOOQGO O O O O O O O O O O O O O C O O O O O OOOOOOOOO 000000000@ 0000000000, nWbiOlvpwNzncvl@OOO.. 0000000009 C O Patented Oct. l5, 1940 UNITED STATES PATENT OFFICE SUBMEBSIBLE PUMP MOTOR John B. Hawley, Jr., Minneapolis, Minn., assigner p to Reconstruction Finance Corporation, Minnef apoiis, Minn., a corporation of the United States Application February 25, 1937, Serial No. 127,674

, 10 Claims.

This invention relates to a portable pump and particularly to such a pump which may be operated either submerged in the liquid to be pumped orv outside of said liquid. The pump is further of the electric motor driven centrifugal or rotary type. Such pumps are generally used for pumping liquid from the holds of vessels, from mines and other places where it is convenient to lower a pump into the liquid to be pumped.

It is an object of this invention to provide a submersible pump driven by an electric motor and having a maximum of protection for the electric motor.

It is a further object of the invention to provide a submersible pump having a novel and efficient impeller structure.

It is another object of the invention to provide a pump of the submersible type having a novel and efiicientfform of sealing means to prevent entry of Water into certain parts thereof.

It is also an object of the invention to provide a pump comprising a casing having a minimum of projecting parts.

It is still another object of the invention to provide a pump of very compact structure so as to have as short length of impeller shaft projection as possible.

It is still further an object of the invention to provide a novel protecting means and clamping means for the motor cable of such a pump.

. It is still another object of the invention to y provide a pump of the submersible type comprising a casing having an electric motor therein with novel means for holding said motor in proper position.

It is still further an object of the invention to provide a pump of the submersible type which is easily handled and the parts of which are easily accessible for maintenance and repair.

-These and other objects and advantages of the invention will be fully set forth in the following description made in connection with the accompanying drawings, in which like reference characters refer to similar parts throughout the several views and in which- Fig. 1 is a central vertical section through the main portion of the pump;

Fig. 2 is a partial view similar to Fig. l shown on an enlarged scale; f

Fig. 3 is a view in end elevation as seen from the left 0f F18. 2;

Fig. 4 is a view in end elevation of some of the parts shown in Fig. 2; f

Fig. 5 is a view in side elevation of the suction end of the pump with the inlet valve and strainer secured thereto;

Fig. 6 is an inner end view of the inlet end member of the pump casing; and

Fig. 'I is a view partly in end elevation showing the inner side of the main impeller and partly in vertical section through the vanes of said impeller.

Referring to the drawings a pump is shown having a main or central casing portion I5. While this portion might be of various forms, in the embodiment of the invention illustrated it is shown as substantially cylindrical, the same having an outer wall I5a and an inner wall I5b, said walls forming an annular chamber I5c therebetween and said inner wall forming a central chamber I5d therein. An end member or suction nozzle I5 is secured to the inlet end of casing I5, said member being of tapering form toward its outer end and having a cylindrical exteriorly threaded inlet portion I6a at its outer end of much lessdiameter than casing I5. Member I6 has a plurality of recesses about the sides thereof forming short tlange portions I6b apertured to receive headed screws I1 threaded into the end of casing I5 and which secure member I6 to casing I5. Member I6 has on its inner side helical distributing plates I6d cooperating with an impeller to be later described. Casing I5 is provided in its end and adjacent its outer side with an annular groove and member I6 has a projecting annular rib I6c tting into said annular groove and engaging a gasket I8 Gasket I8 is compressed in said groove by the rib I6c so that a fluid-tight joint is formed. A motor I9 is disposed in chamber I5d, the same comprising a stator Isa and a rotor ISb. Said stator fits against the wall I5d and is engaged at one end by a cup-shaped member 20 and at its other end by a cup-shaped member 2|. One or more keys 22 are tted in the inner end of member 20 and also in the stator Ila so that said members are keyed together. Casing I5 is provided with a plurality of recesses I5e at its outer side, there being only a thickened portion of wall between the bottom of these recesses and chamber I5d. Said portion of wall has an inwardly tapered threaded opening into chamber I5d and headed drain plugs 23 are threaded into said openingsl one of said drain plugs having its end extending into an opening 20a in member 20. Said latter drain plug therefore functions to prevent rotation of member 20. It will be noted that the heads of drain plugs 23 are disposed in recesses I5e and are thus protected from being struck by any object when the pump is being suspended. Wall I5b is provided in its inner side with annular slots in which are disposed snap rings 24 and 25. Said rings are substantially cylindrical but open at one point so that they can be compressed and inserted into said slots and will remain therein by their expanslve elasticity or resiliency. It will be noted that member 2| has a reduced portion extending along the inner side of snap ring 2l and thus has a shoulder formed thereon engaging the inner side of snap ring 24. Any outward stress on memseated in said groove.`

tTI

ber 2i is thus taken by snap ring 24 and transmitted to the casing wall lib. Just at the outer side of snap ring 24 member 2| is soldered to the inner side of wall lib by solder 2i, which is preferably silver solder. Member 2| has an inwardly projecting central portion bored to receive and have secured therein a bearing 21 illustrated as of the ball bearing type. A shaft 2l is secured to the rotor lsb by a long key 29, said shaft having a slightly enlarged portion between the end of rotor IQb and bearing 21 and having a reduced portion journaled in said bearing so that a shoul der on said shaft engages the inner side of bearing 21 which thus takes the outward or downward thrust of said shaft. A cup-shaped member or housing 3l has an open inner end with a groove formed therein fitting over an annular outwardly projecting rib I5! on the outer end of casing i5 substantially alined with inner wall iid. Member I forms an annular e ltd with member I8 constituting in effect a continuation of annular passage lic. Member Il has a multiplicity of radially projecting lugs apertured to receive headed screws ll threaded into the end of chamber I for securing member Il to said casing. A gasket 32 is disposed in the groove in the end of member and engaged by the rib I5! so that a fluid-tight joint is formed. Member Jl has a central inwardly extending portion Ila having a cylindrical bore in its outer side to form a cupshaped recess and portion 34a at its inner side has a central hub bored to receive a member Il tightly tting therein and having parallel end faces perpendicular to the axis of shaft 2l. Member 2| also has a shallow bore at its outer side in which is tightly fitted a disk-like member I4 having an outer face perpendicular to the axis of shaft 24. A sealing disk 35 preferably made of carbon tightly surrounds shaft 2l and engages the outer face of disk I4. Another similar disk 80 also preferably made of carbon engages the inner face of member Il. Disk 3| has projections 30a extending radially at right angles to each other as shown in Fig. 3 and disk 3l has similar projections. A cage member 31 is provided having a central portion with an inner bore 31a fitting on shaft 2l. At either side of said central portion member I1 has an outwardly projecting cylindrical shell portion 31h and each of said shell portions has formed in its end slots 31e in which are partially disposed the projections 38a. Between bore 31a and its outer side the central portion of member I1 has a plurality of cylindrical bores or holes 31d extending therethrough. Said central portion also has a threaded bore extending radially from the outer side of member 31 to bore 41a and said member isv secured to shaft 24 by a set screw 38, a second setscr'ew alsobeingdisposedinsaidthreaded bore and closing the outer end thereof. Cup washers 4l of thin sheet metal surroundshaft 2l between disks I5 and Il, the same facing said disks respectively and having 11188 a thereon extending into compression coiled springs 4| disposed in the holes 31d. Holes 31d are shown as nine in number and five of the springs 4I are preferably secured at their ends to one washer 40 while the remaining springs are secured at their ends to the other washer 4l. This facilitates handling oi' the springs. Each washer 4I has in its cupped side a flanged ring 44a which extends beyond the edge of washer 4l and engages the outer portion of a resilient ring 42. Ring 42 has a central portion ntting against shaft 2| and this portion is cylindrical at its inner end and is clamped against shaft 2l by a ferrule 40h. Ring 42 has a nange or projecting portion at its outer side which bears against disk or Il. From the described construction it will be seen that springs 4I urge washers 40 away from each other and through the rings 40a press on the outer portions of rings 42 which are in turn pressed against the disks It and It respectively. There is very little outward motion of members 42 against the disks I! and Il and what motion there is is permitted through the flexing of rings 42. The ferrules 4lb have been found to be very important. Without these it was found that relative motion would occur between shaft 2l and rings 42 which would interfere with the proper functioning of the seal. With the present construction the central portion of ring 42 is held in fixed position relative to shaft 2l and any outward motion of the outer portion of the ring is accomplished by iiexing of the ring. Members 33 and I4 in practice have been made of nickel and their faces which are engaged by the disks 35 and are made of some extremely hard and non-corrosive metal. In practice these disks have been coated with stellite, a composition of cobalt, chromium and tungsten. Tungsten carbide has also been used. The disks 35 and It may be made of metal but in practice it has been found very suitable to have these made of carbon. A tight seal is thus effected designed to prevent the passage of any liquid through member 2| or through member Il. Another disk 43 similar to disks It and 48 engages the outer face of member Il at the outer side of member 3l. Disk 48 is engaged by a ring 44 similar in all respects to ring 42 which is engaged at its outer side by a ring 44a similar to rings Ila. A cupped washer 4l receives ring 44a and is engaged at its outer side by a plurality of compression coiled springs 44 disposed in cylindrical sockets formed in the inner or upper side of an impeller member 41 having a hub secured to a slightly tapered portion of shaft 2l by a key 4l. Said hub of impeller 41 has a cylindrical flange 41h extending inwardly about members 44 and 4l, said flange having slots therein at right angles to each other and receiving projections on member 48 similar to the projections "a on member Il. Member 4I is thus driven by member 41 just as member 3| is driven by member I1. Shaft 2l has a reduced threaded end beyond impeller 41 on which is threaded a closed nut 4l having an outer rounded end. A spring washer il is disposed between nut 4l and impeller 41. impeller 41 has inner and outer walls between which extend a plurality oi' spaced varies 41a. The inner or upper wall of impeller 41 is concave and of conical form. An auxiliary impeller Il is disposed betwem member Il and impeller 41, the same having a cylindrical hub of a size to be journaled in the bore of portion 80a. Said auxiliary impeller has a conical wall parallel to the inner surface of impeller 41 and has a plurality of radial blades Ila enginl impeller 41 by which it is driven. A pin lib connects impellers 41 and il so that the latter is driven by impeller 41. It will be seen that a chamber is formed within member` Il between the impeller or pump chamber and the motor chamber Ild. Casing Ii has a recess IW in the side thereof from the bottom of which an opening extends into the chamber in member 3l, the outer end of said opening being threaded and receiving a threaded plug 62. Said plug has a passage therethrough at its inner end having an enlargement outward thereof forming a valve seat with which a ball valve Il cooperates. Ball I8 is pressed toward its seat by a coiled compression spring Il; Spring Il is engaged at its outer end by plug 88 having a central passage therethrough and held in place by a transverse pinv 88.

'I'he upper end of casing Il has secured thereto an upper end member 88. The upper end Iof casing I3 adjacent its outer side has an annular groove therein into which enters an annular rib 88a 'formed on the end oi member 88. A gasket 8l is disposed in said groove and engaged by said rib. Member 60 has a plurality of recesses about the outer side thereof forming short ange portions "b apertured to receive headed screws or bolts 82 threaded into the end of casing I5 for holding rib 89a tightly against the gasket 8| to form a fluid-tight closure. Member 88 is tapered inward its outer end and has a reduced exteriorly threaded cylindrical outlet portion 60e. As shown in Fig. 1 this portion is closed by a cap 88 threaded onto portion c and engaging a gasket 8l held between the same and the end of member 68. Cap 83 has secured -to and projecting from its outer side a. bail handle 83a. Ihe member 28 previously referred to has an inwardly or downwardly extending central portion 2llb bored at its inner side to receive a bearing 88 shown as of the ball bearing type in which is journaled a reduced portion of shaft 28. Bearing 85 is engaged at its upper or outer side by a disk 68 having a central portion thinner than its peripheral portion. Disk 88 is engaged centrally by a screw 61 extending through portion 29h, said screw having a slotted outer end and carrying a jamb nut 88 engaging the outer side of portion h. Disk 88 has considerable resiliency and shaft 28 is thus held with some resiliency lengthwise thereof. An annular plate 63 extends about an inner side of wall lib and at its upper or outer side engages the inner side of snap ring 25. A plurality of circumferentially spaced screws 18 are threaded through plate 89 and engage the outer end of member 20. Member 29 as already stated engages the upper end of stator I3a so that the latter is thus held longitudinally in place by screws 10. It will be noted that the snap ring takes the outward or upward thrust caused by the action of screws 18. The endwise thrust orl stress of the motor is thus taken at both ends by the snap rings 2l and 25. An end cover plate 1I has an annular groove adjacent its outer edge fitting over a projection or rib ISh at the upper end of wall lib and a gasket 12 is disposed in said groove and engaged by said projection or rib. End cover plate 1I has a plurality of lugs at its periphery apertured to receive headed screws or bolts 13 which are threaded into the end of casing I5 and hold said cover plate in place compressing gasket 12 and forming a huid-tight joint. A stuiling box cover 14 of conical cup-shaped form is provided having an annular groove at its inner endinto which lits an annular rib or flange 1Ia on cover 1I, a gasket 15 being disposed in said groove and engaged by rib 1Ia. Member 1l has a plurality of lugs at its periphery apertured to receive headed bolts or screws 16 threaded into cover plate 1I and holding member 14 in place with gasket 15 compressed to form a huid-tight joint. Member 14 has a recess at one side thereof with an opening at its bottom leading to the interior of member 1I, said recess being adapted to receive packing 11. The walls of said recess are interiorly threaded and a packing gland 18 is screwed therein compressing said packing about a cable cover or sleeve 19 passing through said gland and through said opening into member 1l. Cable 19 covers a plurality of conductors 19a, one of which is shown as secured to the upper side of cover 1| by a screw 88 and another of which is shown clamped between nuts 8I threaded onto a rod 82 forming a binding post and extending through cover 1I. Rod 82 has secured thereto at the inner side of cover plate 1l a plurality of conductors 88 held in place thereon-by nuts 8| and passing throughan insulating bushing 84a in member 20. An insulating bushing 88 surrounds rod 82 and is tightly fitted in cover 1I and passes therethrough, the same being enclosed at its outer side by another insulating plug or member 88. Rod or binding post 82 is thus insulated from cover 1 I. Member 68 has a cup-like projection 88d at its upper side adapted to receive packing 81. Member 19 passes outwardly through an opening in member 6l through the packing 81 and through a packing gland 88 threaded into portion 80d and compressing packing 81 about member 19. Gland 88 has an outer portion 88a threaded to receive a pair of headed screws 89 extending through a clamping cap 99 overlying cable sleeve 19 so that the latter is clamped in position by the clamping cap 90. Screws 89 as well as screws I1, 3|, 62, 13 and 18 are shown as having split spring washers 9| beneath the heads thereof. Member 80 is shown as having a ring lug 68e at one side thereof.

In Fig. 5 the pump casing, particularly end member I6, is shown as having threaded thereon and secured thereto an inlet valve member 92. Said valve member has secured at its outer or Alower end a strainer member 93. Members 92 and 33 per se form no particular part of the invention and need not be further described.

The pump can be conveniently transported by using the handle 83a when cap 83 is in place and the pump is not in pumping operation. When the pump is to be used cap 63 will be removed and the discharge hose or conduit will be connected to portion 60e. The pump can be lowered into the hold of a vessel or other desired place by a cable secured in the lug 60e. When it is desired to operate the pump the motor I9 will be started by current supplied through the conductors 19a which will be controlled by a suitable switch. Rntor I9b rotates and shaft 28 is driven. Impeller 41 is rotated and water is drawn through the strainer 93, through the valve 92 which is a regular pump check valve and said water passes from impeller I1 into the annular chamber between members I8 and 30. The water is directed against the distributing vanes I8d on member I6 which assist the ow and distribution of the water and the water passes upwardly through annular chamber I5c, through the annular chamber between members 14 and 80 whichv alines with passage or chamber I5c and the water then passes out through the end of member 60 and is discharged in the desired place by the attached conduits. The auxiliary impeller 5I is driven by impeller I1 and discharges any liquid which may have passed into the cylindrical chamber in portion a. Since the average eilective diameter of the auxiliary impeller 5I is greater than the average diameter of the main impeller 41, the iluid pressure on the seal member 43 is either zero or less than zero or in other words there is a partial vacuum in the chamber in portion 30a. This vacuum reaches about i'lve poundsl when the pump is operating at zero pressure and is at zero when the pump discharge is shut off. It will be seen from this that the auxiliary impeller 5I thus acts to draw out any liquid from portion 30a. and will draw out and discharge any iine particles of dirt or foreign matter which might work through the running fit between the cylindrical portion of lmpeller 5| and the bore in portion 30a. When the pump is running, therefore, there is no tendency for the liquid to pass into the chamber in portion 30a and thus to work past the seal members 43 or 36. It will be seen that by having the auxiliary impeller 5| that the pressure on the sealing members 33 and 34 is substantially zero and that there is a negative pressure on these members at all times when the pump is operating or when the motor is running The seals are subjected to a maximum pressure equal to the submergence pressure when the pump is not running. I'he auxiliary impeller thus constitutes means for limiting the pressure on the sealing members to a small percentage of the discharge pressure of the pump.

It will be noted that by having the springs 4l housed in the impeller l1 the structure is made quite compact lengthwise of shaft 2l. This eliminates extra parts and saves space lengthwise of the pump. This is highly important since the shaft overhang from the lower bearing 2l must be kept as short as possible. It is also pointed out that members 30 and I6 each has one single annular sealing gasket. This results in a structure where both gaskets can be kept tight. It is quite ditilcult to have two parallel gaskets on `one part and keep both tight. The inner gasket 32 is quite inaccessible and it is all the more important to have this gasket kept tight. Members 60, 1| and il also have only'a single gasket and the above remarks apply to these members. Gaskets |60, 32, 60, lla and 12 are of resilient material, preferably containing cork. Members i6, 30, 60, 1| and 1I are drawn down to a metal to metal contact at the sides of the gasket grooves thus assuring concentric assembly, the engaging edges being disposed in planes perpendicular to the central axis of the parts. The member 1I forms a terminal chamber independent of the chamber within member 1I. This forms a convenient chamber for the distribution of the conductors and a convenient connection for a ground conductor for grounding the casing is made by the screw 80. A tight and insulating seal is made by the telescoping members II and 86 which are clamped on member 1I by the nuts 84 and tl. The cable member 19 is flexible so that no strain is put on member 14 by any exterior stresses on the cable. Should any water leak into the chamber in member 'I4 about the cable, this water can be removed by removing member 14 without removing member Il and thus breaking the seal into the motor chamber.

By having the recesses IBe and Ila the plugs therein are protected from striking exterior objects in the handling of the pump. Should the pressure in the chamber between members 2| and 3l exceed the outside pressure and any water be in said chamber it will lift ball valve Il and pass out through plug i2. The pressure within member Il therefore cannot exceed the exterior or submergence pressure plug the pressure of spring 54.

The motor unit is held'by members 20 and 2|. These members react against the snap rings 2l and 25 so that the end thrust is taken by the casing wall. No end thrust of the motor due to holding it in place or due to expansion and contraction of the parts due to temperature can place any pressure on member 'Il and thus cannot affect the seal between member 1| and wall lib of the casing. It should also be noted that no endwise pressure is exerted on the solder 20 since the end thrust of member 2| is taken by snap ring 2|. I'he action of screw I1 on resilient disk Il places a slight tension on shaft 2l. This prevents any axial displacement of the shaft which might disturb the accurate positioning of the sealing disks Il. It and 4I or which might disturb the proper positioning and clearances of the impellers. 'Ihe yielding tension on shaft 2l also acts to prevent any hammer effect due to a shock to the pump due to dropping or other cause.

It is pointed out that since sealing members u and 43 are urged in opposite directions against member 8l that one of these members will be urged to sealing position by the pressure whether the pressure is positive or negative in the cham ber within member 3l. The springs of one of the sealing members will thus always act with the pressure. It is impossible to balance or adjust a spring pressure for a wide range of positive and negative pressures. With the described arrangement as above stated one seal always acts with the pressure whatever the pressure in the adjacent chamber. By having member I! made with parallel sealing faces this part can be made with extreme accuracy. 'Ihis results in a very efficient seal.

By having gland member Il constitute the cable clamp the necessity for a separate or auxiliary cable clamp is eliminated.

From the above description it is seen that applicant has provided a very simple and highly eilicient pump. The pump is designed to withstand the rigorous use to which it is put when submerged at considerable depths. 'Ihe motor is protected from the liquid to be pumped and is mounted in a very emclent manner. The parts are all contained within the outer wall of the casing. The pump has been amply demonstrated in actual practice, found to be very successful and etlicient and is being commercially made.

It will. of course, be understood that various changes may be made in the form. details. arrangement and proportions of the parts. without departing from the scope of applicant's invention, which generally stated. consists in a device capable of carrying out the objects above set forth in the parts and combinations of parts disclosed and defined in the appended claims.

What is claimed is:

l. A structure suitable for use in a submersible pump having in combination, a casing having an inner wall forming a central chamber therein and having an outer wall forming an annular chamber about said inner wall, a stator and rotor disposed in said central chamber, a shaft secured to said rotor, said inner wall having an annular slot at its inner side, a member seated in said slot. means supporting said shaft adjacent one end of said rotor and means reacting Isainst said member and including a member engaging said shaft adjacent the other end of said rotor to hold said shaft and rotor in position longitudinally of said casing.

2. A structure suitable for use in a submersible pump having in combination. a casing having upper and lower ends and having a chamber therein, a driving means in said chamber, a drivingshaftsecuredtoanddrivenbysaidmeans extending longitudinally of said chamber, a bearing for said shaft at the lower end of said chamber taking the longitudinal thrust of said shaft toward said end. a second bearing for said shaft at the upper end of said chamber and shaft and taking the upward longitudinal thrust of said shaft, said shaft terminating in said bearing, a resilient disk extending across the end of said shaft and engaging said second bearing adjacent the edges of said disk and an adjustable member engaging said disk adjacent the center thereof to resiliently press said second bearing lengthwise of said shaft.

3. A structure suitable for use in a submersible pump having in combination, a casing having a substantially cylindrical wall forming a chamber therein, a motor assembly comprising a stator and rotor in said chamber, a member within said chamber engaging one end of said motor assembly, a ring seated in the inner side of said cylindrical wall against which said member abuts, said member being soldered to said wall at the outerlside of said ring.

4. A structure suitable for use in a submersible pump having in combination, a casing having a wall forming a generally cylindrical chamber therein, a driving means disposed in said chamber, a driving shaft driven by said means and extending through one end of said chamber, means at one end of said chamber supporting said shaft and driving means, means reacting against said wall adjacent the other end of said driving means and means reacting against said last mentioned means and including a member engaging said driving means at said other end for holding said driving means in position longitudinally.

5. A structure suitable for use in a submersible pump having in combination, a casing having a wall forming a chamber therein, a driving means disposed in said chamber including a driving shaft driven by said means and extending beyond one end of said chamber, rings engaging said wall adjacent each end of said driving means and abutting said wall longitudinally of said casing, a member reacting against one of said rings, means carried by said member engaging said driving means at one end, means engaging said driving means at its other end and an adjustable means including a member reacting against said other ring and engaging said last mentioned means to hold said driving means and shaft in place longitudinally of said casing.

6. A structure suitable for use in a submersible pump having in combination, a casing, said casing being of general cylindrical form and having a chamber therein, a motor assembly including a stator, a rotor and a shaft driven by said rotor disposed in said chamber, means engaging the wall of said casing for preventing movement of said rotor and shaft lengthwise of said casing, conductors for said assembly extending from said chamber, a cover plate for one end of said chamber, a rod extending through said plate and rigidly held therein to the inner end of which said conductors are connected, insulated means surrounding said rod disposed in said plate and forming a water tight closure therein, a cup shaped member secured to the outer side of said plate forming a tight chamber therein and having a packing recess in the outer side thereof with an aperture through the bottom thereof, conductors secured to the outer side of said rod and extending through said aperture, packing surrounding said conductors in said recess and a packing gland threaded in said recess and compressing said packing about said conductors.

8. A structure suitable for use in a submersible pump having in combination, a casing having a chamber therein, a motor assembly disposed in said chamber including a stator, a rotor and a driving shaft secured to and driven by said means, said shaft projecting beyond one end of said chamber, means tightly closing said chamber at said end about said shaft, a member secured to said casing and tightly closing the other end of said chamber, a second member secured adjacent said first mentioned member forming therewith a tightly sealed chamber, a cable carrying conductors for said motor assembly extending through said second member from the chamber therein, packing carried by said second member about said cable, a third member secured to said casing and making a tight seal therewith forming a passage about said second member, said cable extending through said third member and packing carried by said third member and disposed about said cable, said cable being flexible and constituting the only connection between said second and third members.

9. A structure suitable for use in a submersible pump having in combination, a casing having a chamber therein, a motor assembly in said chamber comprising a stator, a rotor and a driving shaft secured to said rotor, a member secured to said casing tightly closing one end of said chamber, a second member secured adjacent and spaced from said iirst mentioned member and forming a tightly closed chamber between said members, conductors for said motor assembly extending into said last mentioned chamber from without said second member, packing means about said conductors in the wall of said second vmember and means for connecting one of said conductors to said first mentioned member Within said second member.

10. A structure suitable for use in a submersible pump having in combination, a casing having a wall forming a chamber therein, a motor assembly in said casing including a stator, a rotor and a driving shaft secured to said rotor, a member engaging one end of said casing having a sealing means with the end of said wall to seal said chamber at said end and having an outer end portion, a second member having a chamber formed therein and having sealing means engaging said outer end portion to seal said last mentioned chamber, means securing said members together, conductors for said motor extending through the wall of said second member into the chamber therein, means for sealing said conductors in said wall of said second member and insulating means extending through said nrst mentioned member through which certain of said conductors pass into said rst mentioned chamber to said motor.

JOHN B. HAWLEY, Ja.