US2633804A - Pump - Google Patents

Description

April 7, 1953 A. P. BRUCE 2,633,804

PUMP

Filed May 6, 1948 Patented Apr. 7, 14953 UNITED STATES PUMP Alois P. Bruce, Delavan, Wis.

Application May 6, 1948, Serial No. 25,380

This invention relates to improvements in pumps, and in particular to centrifugal pumps of the type commonly used for household water systems of either the deep well or shallow well type.

Conventional centrifugal pumps employ two general types of shaft seals, namely stufIing boxes and rotary seals. The stuing box type of seal has been unsatisfactory not only because it is expensive, but also because it requires periodic adjustment. Conventional rotary shaft seals employ a rotating carbon ring sealvi-ngly mounted on the shaft. This carbon ring is urged axially by a spring against the polished surface of a stationary metallic ring of brass or similar material which is mounted in the pump casing coaxially with the shaft.

In conventional electric motor driven centrifugal pumps the motor and the pump housings are connected by means of an adapter to which both are bolted. The conventional adapter isa unitary member, usually of cast iron, comprising an annular flange to which the motor housing is bolted spaced from a circular plate which is parallel thereto and which serves as the cover platefor the pump. Where a packing gland seal is used, an adapter with substantial spacing between the motor housing ange and circular plate is necessary to provide access for the adjustment of the packing nut.

- It has been common practice to use on the rotary seal type of pumps an adapter which is approximately the same size as that used on the packing gland pumps. In the adapter heretofore used with rotary seal pumps, the plate forming the cover for the pump is formed with an outwardly projecting dome shaped portion surrounding the rotating shaft, the shaft seal being mounted in this projecting portion of the adapter. This dome shaped portion required that the motor to be spaced away from the pump housingsu'bstantially the same distance as was required by the use of a packing gland, and therefore necessitated a relatively large and expensive adapter. In addition, when the adapter having the dome shaped plate was used on a vertical pump, this dome portion had to be provided with a vent valve to release air which would otherwise bev trapped thereunder upon priming of the pump. If the vent valve were not provided on this type of adapter, the rotary seal would burn out after a short running time because of lack of lubricating and cooling water.

When centrifugal pumps are used for deep well purposes, a jet eductor is used in conjunction 3 Claims. (Cl. 10S-87) therewith in order to raise the water from the lower levels. When an eductor is used, a pressure regulating valve must be provided in the discharge of the pump. Conventional pressure regulators are expensive and complicated devices which are provided with externally accessible, adjustable means for varying the pressure which is to be maintained by the regulating valve. Such pressure regulating valves are set for the proper pressure at the factory and, though they are adjustable, they rarely, if ever, require adjustment after leaving the factory.

It is therefore a general object of the invention to provide .a centrifugal pump having a rotary shaft seal which is operative equally well in either horizontal or vertical position and which requires no vent valve adjacent said shaft seal to provide for proper priming thereof.

A further object of the invention is to provide an electrically driven centrifugal pump which does not require an adapter for mounting the electric motor thereon.

A further object of the invention is to provide an improved centrifugal pump wherein a rotary shaft seal coacts directly with the housing cover plate thereof.

A further object of the invention is to provide an electrically driven pump of the class described which, by reason of the absence of an adapter, is a very compact unit.

A further object of the invention is to provide a centrifugal pump which may be adapted for deep well purposes by associating therewith a novel pressure regulating valve having very few component parts.

A more specific object of the invention is to provide a pump having an adjustable pressure regulating valve wherein access to an internal adjustment member may be quickly and easily obtained by removal of a screw plug therefrom.

Further objects of the invention are to provide a pump of the class described which is strong and durable, which may be quickly assembled and disassembled, which is inexpensive to manufacture and repair, and which is otherwise well adapted for the purposes described.

With the above and other objects in View, the invention consists of an improved pump, and all its parts and combinations as set forth in the claims, and all equivalents thereof.

In the drawing accompanying and forming a part of this application, wherein is shown one complete embodiment of the preferred form of the invention, and wherein the same reference aesaeofi numerals indicate the same parts in all of the Views:

Fig. l is a fragmentary side view of an improved electrically driven pump equipped with the improved pressure regulating valve, parts being broken away and shown in section; and

Fig. 2 is an enlarged fragmentary vertical sectional View of a portion of the interior of a modified form ofthe improved pump.

Referring more particularly to the drawing, the numeral 5` indicates the improved pump and the number 6 indicates the improved pressure regulating valve associated therewith. Numeral l' indicates an electric motor for driving theA pump 5.

The pump 5 shown is of the type convention ally known as a centrifugal pump and comprisesa housing 8 having a centrally located inlet 9, which is threaded to receive an inlet conduit-vill, and having a pair of outlets H and l2. The housing'iis; commonly. called a volute,V and is provided inl its 'upper' surface with a central chamber i9 in whichanY impeller ifi-is rotatably mounted. The inlet e communicates with the chamber lfbas'shown'in Fig.. l. The impeller Mf is threadedly mounted on the shaft l5 of the motor lfand rotatesatherewith in the chamber Isf The'impeller l isV formed with aV preferably flatv upper surface, a central inlet i6 andA with channels-Ii whichQextend'from-the inlet is to thezperiphery i8 thereof. The portion of the side Wall of the chamber is adjacent the periphery'of theimpeller l@ is formed in the conventional' manner with a spiral recess which communicates in the'usual vway with a discharge chamberil of the housing 8*. A cylindrical recess i3 having a diameter larger than the diameter of the impeller I4 communicates with the chamber i9 and extends to the upper end of the volute 8. y

A substantially flat cover plate 2l is adapted to t the volute 8 therebygenclosing chamber ISand recess i3. The cover plate 2l is provided with a centralv aperture '22 to permit passage therethrough ofthe motor shaft i5.k A suitable gasket`23A` is interposed between the plate?! and the housing 8 to prevent leakage. The plate 2l is preferably of brass or other suitable material such a'sfrustY resistant bearing material and is preferably provided' with' a smoothly lfinished annular area on the under surface thereof surrounding' the aperture22.'" The upper surface of the impeller hl is preferably provided with' a centrally disposedcircular recess 2li surrounding thelower portions of theshaft-L The flat upper' surface of the impeller is preferably spaced fromv the plate 2i a distance substantially less than one-half the radius' of the impeller, as shown in'- the drawing.

Mounted on the shaft l-between the plate 2l andthebase of the recess llis a rotary shaftv seal assembly 25.. Fig. 2 shows-on an enlarged scale a shaft seal assembly 2F# which is in all'rerspects .identical to the assembly 25. of `the assembly.Y 25 are indicated by primed reference .numbersV corresponding tothoseof the same parts of the assembly 25. The assembly 'iscomprised of a carbon ring 2E which slidably and lrotatably engages the smoothly finishedannular area of the plate 2l surrounding the aperture 22. The carbon ring E has a smoothly finished upper surfaceA or seal face which coacts with the smooth annular surface of the plate 2 i to prevent leakage therebetween. The carbon ring A2S' is preferably backed with aflanged fric-ry The partsy tion sleeve 2l of rubber or other suitable resilient material which closely ts the shaft l5 in a manner to prevent any leakage along the shaft between the shaft and the sleeve 2l.

A metallic ring 28 having an inwardly flanged lower end preferably surrounds and engages the ring 26 and the flanged portion of the sleeve 2l' in any suitable manner to prevent rotation of the ring 2t relative to the sleeve 28. A second metallic ring 52 preferably surroundsthe unflanged portion of the sleeve 28. The upper end of a preferably helical spring 2S engages the flange of the ring 2t, and the lower end of the spring 29 is seated in the recess 24 of the impeller le. The springvZQ, acting through the sleeves 28 and 21, urges the'ring 25 into engagement with the plate 2l with sufficient pressure to maintain a watertight seal therebetween at all times.

Amodied form of the pump 5 is shown in Fig. 2 wherein the impeller ill; thereof is not provided with arcentral recess-in its upper.v surfaceadjace'nt themotorfshaftl 5! FigiZ alsoshows 'alternative construction` wherein the'lplate 2i may beim'ade of vaniinexpensivemetal such asste'el. Theplate 2 l is provided with an insert 39, of brass or other suitable'material such`Y as rust resistant bearing material, mountedv in a recess 31 formed ini'its under-'surface concentric with the: aperturef 22'.. The insert 'Sfr is preferably-sealed in"the.'recess 3fm any suitablemanner toprevent leakage'between the insert andtheplateZ l The 'lower surface'iof `the "inserti 3u is preferably: smoothlyy finished. 'Ihe'frotary sealassembly 25`I is identical with the'rotaryy seal assembly 25 of Fig. l, and it coacts with thesmooth surface of the insert so' inthe same Amanner'as the rotary seal 25 coacts with thesmooth' annular surface por-v tion of the plate 2l- `of the'pref'erred form;

Whenthe pump 5 is Vused for `shallow well purposes, the-discharge outlet Il is usually'plugged and the'discharge: lZ-is connected with the water distribution system. However,y When'the pump 5is used for-deep1well purposes', a conduit 32.is threadedly connected to the dischargewopening l l and leads downwardly to aA jet (not shown) mounted v in the lower end of the'inlet conduit lo.' A nipple 33 threadedly connects.v the' disi-t charge-outlet I2-- with the pressure regulating.' valve B.

The valve t is comprised of' a substantiallytubular body 34 which is provided with a'tubular extension 35 projectingzatan angle therefrom.

by'the'webss; is a hubil.- Theouter end face:

40 ofthehub is Yforrned With'anaxial bore 4l inv which isfthreaddly mounted-f. an axially extending Vadjustment screw s2. of the hub V,39 and the annular valve seat 37 extend inlsubstantially the same plane.

A valve member 43 of rubber or other suitableV materialya'ndn having the `shape `of a centrally apertured disc, is mounted -on the screwllzin` a manner to1 cooperatevwith ,the surface 40 of the hubI 39 and the annular seaty 3l'. When the' valve member 43 is'seated on the` surfaces 31 and 40, as shown infFig. 1, no fluidwill pass through the valve. Ametallic backing disc .44 having a central aperture and having a peripheral flangey ispreferably positioned. against 'the`- The outer surface .40

erably interposedzbetween'the head of the screw 42 and the backing disc ,44 in a manner to urge the valve member 43 axially against the` seats 31 and 40. It is apparent that the pressure exerted on the valve member 43 by the spring 45 may -.bevaried by turning the adjusting screw 42 either inwardly or outwardly.

The outer end of the body 34 is suitably threaded as at 46 to receive a removable plug 41. Inwardly of the threading 46 the body 34 is formed with an annular groove 48 to receive an annular gasket 49. Inwardlyadjacent the groove 48 the body 34 is formed with, a portion of reduced internal diameter to form a vshoulder 50. Itis apparent that the portion of the gasket 48 interposed between the peripheral portions of Vthe inner surface of the plug 41 and the shoulder 50 prevents any leakage between said plug and said shoulder. A conduit I is threaded into the tubular extension 35 and may be connected with the conventional water distribution system.

The adjustment screw 42 is set at the factory to provide for the exertion of the proper amount of force on the valve member 43 by the spring 45. Under ordinary conditions, this setting need never be changed. If, however, it is found necessary to vary the setting of the adjustment screw 42, it is necessary only to remove the plug 41 from the body 34 by unscrewing the same. This provides ready access to the adjustment screw 42 which may be turned with a screw driver.

'Upon replacement of the plug 41 the valve 6 is again ready for operation.

Operation In operation, the spring 45 will maintain the valve member 43 seated against the surfaces 31 and 40 until a predetermined pressure has been built up in the discharge chamber 20 of the pump 5. When the pressure in the discharge chamber 20 rises above this predetermined amount, it will force the valve member 43 axially outwardly along the stem of the adjustment screw 42. In so doing, the pressure in the chamber 20 overcomes the force exerted on the valve member 43 by the spring 45. Water will then flow from the chamber 23 through the nipple 33, through the valve 6, and out the conduit 5I. Whenever the pressure in the discharge chamber 20 drops below the predetermined amount, it will no longer be able to overcome the force exerted on the valve member 43 by the spring 45, and the spring 45 will therefore force the valve member 43 inwardly against the seats 31 and 40 to stop the now of water through the valve.

The operation of the pump 5 is substantially the same as that of conventional centrifugal pumps. However, by the use of the improved cover plate 2l, the use of an expensive and bulky adapter has been eliminated. Upon priming the improved pump 5 (through a priming opening not shown), the entire volume of the chamber formed by the recess I3 and the cover plate 2l lls with water, there being no dome-shaped portions in the improved housing cover plate under which air can be trapped and from which said air must be vented, as is the case with adapters for conventional pumps having rotary seals.

The improved cover plate 2| permits mounting of the motor 1 directly thereagainst, as shown in Fig. 1, thereby providing a very compact unit. The improved pump and pressure regulating valve are substantially fool-proof and can be quickly and easily assembled or disassembled by reason of the small number of component parts therein. YIn addition, the substantial reduction in the number of parts in the improved pump and regulating valve greatly reduces the cost of manufacture thereof.

Various changes and modifications may be made without departing from the spirit of the invention, and all of such changes are contemplated, as will come within the scope of the claims. v

What I claim is:

1. A n electrically driven pump comprising: a rotary shaft; a rotary impeller having one side substantially flat and connected to said shaft, said impeller having a single water inlet, formed in its opposite side; a housing having a chamber in which said impeller rotates, said housing having a recess of a diameter greater than the diameter of the impeller communicating with and extending outwardly from said impeller chamber, and said housing having a rim portion surrounding the outer end of said recess and spaced axially from said impeller; a thin flat cover plate having one side seated on said rim and having a central opening through which the rotary shaft extends, the flat side of said impeller being spaced from said plate a distance substantially less than one-half the radius of said impeller; a driving motor for said shaft mounted directly on the other side of said thin fiat cover plate; bolts projecting from said motor into said housing rim for removably connecting said motor and cover plate in assembled position; and a rotary seal on said motor shaft extending between said cover plate and the impeller.

2. An electrically driven pump comprising: a rotary shaft; a rotary impeller having one side substantially at and connected to said shaft, said impeller having a single water inlet, formed in its opposite side; a housing having a chamber in which said impeller rotates, said housing having a recess of a diameter greater than the diameter of the impeller communicating with and extending outwardly from said impeller chamber, and said housing having a rim portion surrounding the outer end of said recess and spaced axially from said impeller; a thin flat cover plate having one side seated on said rim and having a central opening through which the rotary shaft extends, the flat side of said impeller being spaced from said plate a distance substantially less than one-half the radius of said impeller, said cover plate being formed in said side with a central recess; a single flat annular insert of rust resistant bearing metal mounted in said recess; a driving motor for said shaft mounted directly on the other side of said thin flat cover plate; bolts projecting from said motor into said housing rim for removably connecting said motor and cover plate in assembled position; and a rotary seal on said motor shaft extending between said cover plate insert and the impeller.

3. An electrically driven pump comprising: a rotary shaft; a rotary impeller having one side substantially fiat and connected to said shaft, said impeller having a single water inlet, formed in its opposite side, and said impeller being formed in said at side with a circular recess concentric with said rotary shaft; -a housing having a chamber in which said impeller rotates, said housing having a recess of a diameter greater than the diameter of the impeller communicating with and extending outwardly from said impeller chamber, and said housing having a rim portion surrounding the outer end of said recess ageasgfsba 8 REFERENCESZJCITED:

Theoll'owing references alzel `of "record -in 'the file'v of` this patentz' UN'IfED STATES PA'IfENTs

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