US2496870A

US2496870A - Self-priming pump

Info

Publication number: US2496870A
Application number: US717517A
Authority: US
Inventors: Albert J Granberg
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-12-20
Filing date: 1946-12-20
Publication date: 1950-02-07
Anticipated expiration: 1967-02-07

Description

Feb. 7 1956 A. J. GRANBERG 2,496,870

SELF-PRIMING PUMP 5 SheetsShe et 1 Filed Dec. 20, 1946 BY 662 7 M H/SATT'ORNEYS Feb. 7, 1950 GRANBERG 2,496,870

SELF-PRIMING PUMP Filed Dec. 20, 1946 3 Sheets-Sheet 2 IN! ENTOR. ALBAWT J @m/vBE/w law HAS A T TORNEVS Feb. 7 1950 J. GRANBERG Q 2,496,870

SELF-PRIMING PUMP Filed Dec. 20, 1946 3 Shets-Sheet 5 HAS A 7' TORI EKS' Patented Feb. 7, 1950 UNITED. STATES PATENT OFFICE 2,490,870 SELF-PRIMING rum Albert J. Granberz, Oakland, Calif. Application December 20, 1946, Serial No. 717,517 7 Claims. (Cl. 103-413) My invention relates in general to pumps and more particularly to an impeller pump assembly having self-contained priming features.

Among the objects of my invention are:

(1) To provide a novel and improved selfpriming pump assembly;

(2) To provide a novel and improved selfpriming impeller pump assembly;

(3) To provide a novel and improved impeller pump assembly capable of pulling a high vacuum;

(4) To provide a novel and improved self= priming pump assembly involving but a single priming valve to control feed of priming liquid to the pump;

(5) To provide a novel and improved impeller pump which may be readily adjusted and serviced;

(6) To provide a novel and improved impeller pump having the ability to scavenge itself of a substantial portion of accumulated air.

Additional objects of my invention will be brought out in the following description of a preferred embodiment of the same taken in conjunction with the accompanying drawings wherein- Figure 1 is a longitudinal view in section through a pump assembly embodying the features of my invention;

Figure 2 is a view in section taken in the plane 2--2 of Figure 1 and showing the impeller casing partly broken away;

Figure 3 is a view in elevation of a iragmentary portion of the pump assembly of Figure 1;

Figure 4 is a view in section taken in the plane 4-4 of Figure 1;

Figure 5 is a view in section through a gland embodied in the pump assembly of Figure 1;

Figure 6 is an end view of the gland assembly of Figure 5.

For the details of the preferred embodiment of my invention, reference will be made to, the aforementioned drawings. The pump assembly being of the impeller-type, it embodies an impeller I of more or less conventional design having a plurality of radial passages 3 defined by involute partitions 5 radiating outwardly from the central region of the impeller to the peripheral edge thereof, such passages connecting with an axial inlet passage 1 iormed in an axial extension 9 of the impeller on one side thereof. On the other side, the impeller is formed with the hub II for mounting on a drive shaft ii.

The impeller casingis formed of two sections it and ll respectively, bolted together, each having an axial opening countersunk to provide an axial recess for each axial end of the impeller.

The priming chamber i9 is cast integral with the casing section it and is provided with a central opening 2! in the roof thereof for initial priming purposes.

Formed alongside the priming chamber and as an integral part thereof is an inlet passage or suction line 23, a portion 25 of which passes through the priming chamber, terminating at the axial inlet passage l in the impeller. Such portion of the inlet passage tapers to provide a valve seat. At this point the passage has one or more openings 2? to the interior of the primlng chamber whereby an immediate supply oi liquid from thepriming chamber to the impeller will be available when such openings are exposed to the inlet passage.

Such openings, however, are adapted to be normally closed by a valve 29 involving a tapered ring 3! connected by a plurality of radial spokes $3 toa central hub 35, whereby regardless oi the position of the. valve, whether it be seated or unseated, it will permit a substantial normal flow of liquid to the pumpthroug-h the inlet passage. 1 The valve is mounted on a valve stem 3? extending out of the inlet passage through an opening in the wall thereof. Such opening is covered by a housing 39 bolted into position and provided with a wall 4! extending part way across the opening. Such wall has bolted thereto a baflie or guide 43 at the turn in the inlet passage to avoid turbulence, as the liquid flows through the inlet passage to the pump impeller. Both this wall and baffie are perforated to receive a long bushing through which the valve stem slidably passes.

Pivotally mounted on a lug Al depending from the roof of the housing, is a bell crank lever having. a vertically directed arm 69 adjustably afnxed to the end of the valve stem 3'5, and a horizontally disposed arm 51 terminating at its end in a weight 53, causing a pull on the stem tending to unseat the valve. The amount 0! guano.

pressure of the inflowing liquid against the valve,"

such drop in pressure being occasioned by a decrease of velocity of such liquid.

Such drop in velocity may be caused either. by a diminishing supply of liquid at the source from which such liquid is being pumped or by the undesired introduction of substantial quantities of air into such liquid. In either case, the gases entrained in the liquid entering the impeller will tend to accumulate as gas bubbles along the surfaces of the pump components, and in the absence of precautions will ultimately cause the pump to lose prime. Before this condition can occur, however, in the pump assembly described above, the valve will become unseated and a prompt supply of liquid from the priming chamber will be available.

An involute channel 55 along the inside periphery of the pump casing, terminates in a discharge opening 51 to the priming chamber, and at the top of such priming chamber, a threaded opening is provided for a discharge pipe connection 59. Thus the priming chamber gets first call on the discharge from the pump impeller, and if the source of supply for the pump has run dry, the liquid in the priming chamber will circulate through the impeller and continue to maintain prime in the pump.

Adjacent to and transverse of the periphery of the impeller and lying in the discharge stream, are a plurality of trimmer lugs i and 63. The first of these trimmer lugs is shaped to present an inwardly deflecting bailie surface 54 terminating in an edge 65 in close proximity to the impeller rim. The succeeding lug 63 presents a stream-line surface to the flow of liquid and terminates in a relatively sharp edge 66 in skimming relationship to the rim of the impeller.

It is characteristic of impeller-type pumps that a substantial portion of air introduced into these pumps tends to separate out and accumulate as a layer of air bubbles on the outer periphery of the impeller. It is desirable in a pump of this type to either preclude the formation of such bubbles if possible, or efiectively remove the same if and when they appear.

The aforementioned trimmer lugs serve this latter function, the foremost of such lugs functioning as a baiile to deflect such air bubbles inwardly of the impeller. This not only frees these bubbles from attachment to the impeller, but in The number of lugs required to reach maximum eiliciency in the removal of such air bubbles from the impeller is small, for beyond that point where most of the air has been removed, the

addition of more lugs will have little additional effect.

A feature of the priming chamber as described resides in the fact that all openings thereto are above the elevation of the impeller and easing, thereby assuring without reliance upon valves, that the chamber will remain full after each cycle of pump operation.

The section I! of the impeller casing is in the form of a disc having extending axially therefrom a pair of aligned tubular sections 61 and 69 respectively, connected together by a top rib H and angularly disposed base ribs 13, the two sections being thus supported in spaced relationship to each other.

That tubular section 51 provides a housin for a packing gland assembly involving a plurality of layers of packing 15 under pressure of a packing gland ll mounted on the shaft l3. Such gland is formed of a pair of longitudinal half sections 19 adapted to fit about the shaft within the packing gland housing, each such half section terminating in a complementary lateral flange 8| exposed in the space between the two tubular sections, each such flange being perforated to permit passage of a clamping bolt 83. The length of the gland is somewhat less than the aforementioned spacing to permit deflecting them inwardly, their tendency to rebound under the action of the fast rotating impeller causes them to acquire sufficient momentum to carry them into the path of the succeeding trimmer lug which skims them off and guides the same into the discharge flow.

By tapering that edge 68 of the casing discharge opening facing the rotational movement of the impeller, and terminating it in skimming relationship to the impeller rim, any of the inwardly deflected bubbles which rebound beyond the second trimmer lug, may be skimmed off.

Such removal of the peripheral layer of bubbles from the impeller, serves to relieve the more inwardly anchored air bubbles of a certain amount of back pressure whereby they become more weakly anchored. The centrifugal action of the impeller can, under these conditions more readily dislodge such bubbles, and this is aided somewhat by such turbulence as is created by the inward deflection of the bubbles from the peripheral layer.

withdrawal of the gland sections from the housing and thus provide access to the packing.

The gland is held in functional position against the packing, by suitable holding means. Toward this end, I provide diametrically spaced ears extending laterally from the gland assembly housing, each of these ears being notched to provide anchorage for one of the clamping bolts 83. A retainer cap 81 slidably mounted on that portion of the shaft exposed between the tubular sections, is adapted to fit over the gland, and has bolt openings therethrough matching those in the gland, whereby bolts anchored in the ears 85 might pass and be secured as by a tightening nut 89.

A trough cast integrally with the base ribs 73 below the gland, serves as a catch basin for drippings or the like which might, at some time or another, develop.

A pair of shaft bearings 9| are located in the other tubular section 69 through which the drive shaft passes, and the exposed sides of each of such bearings is covered by a dust seal 93 held in position by a locking ring 95.

These bearings are maintained in properly spaced relationship by a spacing sleeve 1 91 mounted on the shaft. Axial adjustment of the impeller I in its casing is provided for by cutting a relatively broad circumferential groove 99 in the drive shaft at a point covered by the spacing sleeve, and by means of radially disposed set screws ii in the sleeve, the sleeve and drive shaft may be locked together at some point within the limits permitted by the width of such groove.

In order that such adjustment may not be disturbed by the influx of liquid to the pump impeller, I provide passages )3 through the impeller hub, which serve to equalize the hydrostatic pressure between the inside and outside of the impeller and thereby largely neutralize the thilust of the incoming liquid against the impe er.

In that tubular section which houses the bearings, I provide a radial opening in line with the drive shaft groove whereby the set screws may be rendered accessible by means oi a screw driver. for eiiecting such aforementioned axial adjustment oi the impeller. This opening is preterably threaded for the reception of a grease cup I" which serves to maintain lubrication of the bearings. when axial adjustments of the impeller are to be made, however, such grease cup may be readily removed for the purpose.

From the above description of my invention in its preferred form, it will be apparent that the same fulfills all the objects as previously recited. Therefore, while I have described such embodiments in considerable detail, I do not desire to be limited in my protection to such details except as may be necessitated by the appended I claim:

l. A self-priming impeller pump assembly comprising an impeller; -a casing enclosing said impeller and having an axial input opening to said enclosed impeller; a priming chamber; ,an input passage leading to said input opening and having a wall exposed to the interior of said priming chamber, said passage having at least one connecting opening therethrough to the interior of "said priming chamber; a valve disposed in said passage. and adapted in its seated position to close said connecting opening, said valve having an opening therethrough to permit substantial normal flow through said input passage and a valve stem extending therefrom through the wall 01 said input passage; and means adapted to withdraw said valve from seating position upon drop of hydrostatic pressure of flowing liquid against said valve, to expose said connecting opening and permit flow of liquid from said priming chamber into said input passage.

2. A sell-priming impeller pump assembly comprising an impeller; a casing enclosing said videavalveseahandatleastoneeonnecting.

against said valve, to expose said connecting.

opening and permit flow of liquid from said priming chamber into said input passage, said means including a pivotally mounted bell crank lever having a pair of moment arms, one of said arms being connected to said valve stem and the other of said arms terminating in a weight sumclent to unseat said valve on the occasion of such drop in hydrostatic pressure.

4. A self-priming impeller pump assembly comprising an impeller; a casing enclosing said impeller and having an axial input opening tosaid enclosed impeller; a priming chamber adjacent said impeller casing; an input passage through said priming chamber to said casing'input opening, said passage having a tapering interior wall adjacent said casing opening to provide a valve seat, and at least one connecting opening to the interior of said priming chamber through said valve seat; a valve disposed in said passage, said valve including a ring having a taper complementary to said valve seat, and a central section connected to said ring by a plurality of radial spokes angularly spaced to permit substantial normal flow through said input passage, a valve stem connected to said central section and extending through the wall of said input passage:

- and means adaptedto withdraw said valve from impeller and having an input opening to said enclosed impeller: a priming chamber; an input passage leading to said input opening and having a wall exposed to the interior oi said priming chamber, said passage having at least one connecting opening therethrough to the interior of said priming chamber; a valve disposed in said passage, and adapted in its seated position to close said connecting opening, said valve having an opening therethrough to permit substantial normal flow through said input passage and a valve stem extending therefrom through the wall of said input passage; and means adapted to withdraw said valve from seating position upon drop of hydrostatic pressure oi flowing liquid against said valve, to expose said connecting opening and permit flow of liquid from said priming chamber into said input passage, said means including a pivotally mounted bell crank lever having a pair of moment arms at substantially right angles to each other, one of said arms being connected to said valve stem and the other of said arms terminating in a weight sumcient to unseat said valve on the occasion of such drop in hydrostatic pressure.

3. A self-priming impeller pump assembly comprising an impeller; a casing enclosing said impeller and having an axial input opening to said enclosed impeller; a priming chamber adiacent said impeller casing; an input passage through said priming chamber to said casing input opening, said passage having a tapering interior wall adjacent said casing opening to pro- 5 casing adjacent the rim or said impeller, and a seating positionupon drop of hydrostatic pressure or flowing liquid against said valve, to expose said connecting opening and permit flow of liquid from said priming chamber into said input passage, said means including a pivotally mounted a bell crank lever having a pair of moment arms at substantially right angles to each other, one or said arms being adiustably connected to said valve stem and the other of said arms terminating in a weight sumcient to unseat said valve on the occasion or such drop in hydrostatic pressure.

5. An impeller pump comprising an impeller, a casing enclosing said impeller, said casing having an axial input opening to. said impeller and a discharge opening in the periphery of said plurality of stationary trimmer lugs transverse to the rim of said impeller in said opening, certain of said trimmer lugs having a tapered edge in skimming relationship to said impeller rim.

so 6. An impeller pump comprising an impeller,

a casing enclosing said impeller, said casing having an input opening to said impeller and a discharge opening-in the periphery of said casing adjacent the rim of said impeller, and a plurality of stationary trimmer lugs transverse to the rim of said impeller, the first of said trimmer lugs having an inwardly deflecting baiiie surface ter-' minating in an edge in close proximity to said rim and a succeeding lug having a tapered edge in skimming relationship to said impeller rim.

7. An impeller pump comprising an impeller,

' a casing enclosing said impeller, said casing hav-' 1 ing an input opening to said impeller and a discharge opening in the periphery oi" said casing adjacent the rim or said impeller, and a plurality 7 ct stationary trimmer lugs transverse to the rim oi said impeller, the first or said trimmer lugs having an inwardly deflecting baille surface ter- "3 7a: urinating in an edge in close proximity to said 1 0652131 rim, and a succeeding lug having a tapered edge 5 in skimming relationship to said impeller rim, 1'969881 and that edle of said casing discharge opening facing the rotational movement of said impeller 5 2 also being tapered and in skimming relationship 365 to said impeller rim. 10 2:109:80 ALBERT J. GRANBERG. 2,281,682 2,250,983 REFERENCES CITED 2,391,789 2,394,932 The following references are oi record in the 15 i s file of this patent:

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