US2220538A

US2220538A - Pump

Info

Publication number: US2220538A
Application number: US156528A
Authority: US
Inventors: Neibert Harold
Original assignee: MICRO WESTCO Inc
Current assignee: MICRO WESTCO Inc; MICRO-WESTCO Inc
Priority date: 1937-07-30
Filing date: 1937-07-30
Publication date: 1940-11-05
Anticipated expiration: 1957-11-05

Description

I H. NEIBERT Nov. 5, 1940.

PUMP

3 Sheets-Sheet l I. IIII 7 Filed Ju] .y 30, 1937 INVENTOR Harold Neibert awn 144 738 ATTORNEYS 3 Sheets-Sheet 2 INVENTOR Hare ld .lvizibert ATTORNEYS H. NEIBERT Nov. 5, 1940.

PUMP

Filed July 30, 1937 IPUMP Filed July 30, 1937 3 Sheets-Sheet 3 v INVENTOR Harold lvieilzeri; BY

ATTORN EYS Patented Nov. 5, 1940 UNITED STATES PATENT OFFICE 2,220,538 PUMP Harold Nelbert, Davenport, Iowa, asllgnor to Micro-Westco, Ina, Bettendorf, Iowa, a corporation of Delaware Application July 30, 1937, Serial No. 156,528

90mins.

vided with means so that each time they are started they will evacuate air or gas from the suction line and draw liquid. A pump of this type 10 is commonly referred to as a self-priming pump, since it is unnecessary that an attendant pour liquid into the pump each time it is started into' operation. However, it is well known that even the so-calied self-priming pumps must have a 15 small quantity of liquid in the pump channel or admitted thereto when the pump is started in order for the impeller to evacuate the air or gas from the suction line. The amount of such water required in the pump chamber to enable the pump to prime itself varies with diflerent designs. It is desirable that the amount of such initial liquid be reduced to a minimum, and the present invention aims to attain this end.

Another object of the invention is to provide a 25 self-priming pump which quickly evacuates the air or gas from the suction line and is positive and reliable in operation.

Another object is to provide a pump of this character which is simple in design and construction and inexpensive to manufacture, and in which the self-priming feature requires a minimum amount of material and labor in addition to that required for constructing the pump proper. 'A further object-is to provide means for mak- 35 ing a rotary impeller type pump self-priming, which may be applied to previously built pumps of this type which were not self-priming, with a minimum 01' expense and alteration therein.

Other objects and advantages will become ap- 40 went from the following detailed description of suitable embodiments of the invention, made in connection with the accompanying drawings, in

Fig. 4 is a fragmentary detail, in section, takenv substantially on the line 4-4 of Fig- 2? Fig. 5 is a fragmentary detail sectional view taken substantially on the line 5-5 of Fig. 1;

Fig. 6 is a view similar to Fig. 3, showing a modification of the invention:

Fig.7 is,a detail view, in section, taken sub- 5 stantiaily on the line 1-1 of Fig. 6;

Fig. 8 is a view like Fig. 3, showing another modification of the invention;

Fig. 9 is a detail view, in section, taken substantial-ly on the line 8-9 of Fig. 8; 10

Fig. 10 is an end elevational view, partly in section, and-with parts removed, of another rotary impeller type pump embodying the present invention;

Fig. 11 is a vertical sectional view, with parts removed, taken substantially on the line ll-ll of Fig. 10;

Fig. 12 is' an enlarged fragmentary detail view, in section, taken substantially on the line l2-l2 of Fig. 10; V

Fig. 13 is a partially diagrammatic illustration of an end view of a pump like that illustrated in Fig, 10, with the associated pipe connections;

Fig. 14 is an enlarged fragmentary detail, partly in section, of the outlet end of the pressure developing channel of the pump illustrated in Fig.

Fig. 15 is a fragmentary detail, in section, taken substantially on the line lI-l6 of Fig. '14;

Fig. 16 is a view similar to Fig. 14, illustrating a modification of the invention; and

Fig. 17 is a fragmentary detail view, in section, taken substantially on the line ll-ll of Fig. 16.

The rotary pumps to which the priming means of the present invention may .be applied are of various well known types, and those shown in the drawings are for purposes of illustration and description, it being understood that the invention may be applied to numerous other forms of rotary pumps. The pump itself forms no part of the present invention, and for this reason various parts and details of construction have been omitted.

Referring to the drawings by numerals of reference which identify and have been applied to like parts throughout the several views, the pump comprises a rotary impeller i usually of relatively flat, disklike form, and provided with a plurality of radially directed buckets 2 formed on its peripheral marginal edge. A set of buckets is formed on each side of the rotor or impeller I and separated by a circumferentially extending web 3. The individual buckets in each set are separated from one another by radial webs 4.

The .impelleris secured on ,a shaft I5 and is outlet I5. The inlet communicates with an intake passage it formed in a boss I! at the top of the casing "I, and the outlet communicates with a discharge passage I8 formed in a boss I9, also at the top of the casing I and adjacent the boss II. Each of the bosses is suitably threaded to have intake and

discharge pipes

20 and 2|, respectively, secured thereto.

Between the inlet I4 and outlet IS the rings Ill and II closely surround the impeller I so that during operation of the pump liquid flowing through the pressure developing channel I2 is directed 'throughthe outlet I5. This closely fitting part of the rings is referred to as a stop, and indicated by the numeral 22.

Radially inward from the channel I2 each of the inlet I4 and outlet "to permit the ingress and egress of liquid to and from the channel H. In the region of the stop 22 portions 21 of the ribs 25 extend to a position closely adjacent the periphery of the impeller I and have a running fit therewith to cooperate with the stop in directing liquid through the outlet ll.

Although the-pressure developing channel I2 is described as being defined by the removable annular rings Ill and II, this construction is not an essential part of the present invention, and the self-priming feature may be incorporated in a pump in which the pressure developing channel is formed in the casing I or. cover plate 2, or both.

When operating a pump of this character intermittently, for example when the pump is part of a domestic water system, there are occasions when the pump is idle for an extended period of time so that the intake pipe 20 may lose its liquid content and become filled with air or gas. Upon actuation of .the pump this gas is initially drawn into the channel I2 and tends to be forced through the out'et it until the liquid to be pumped again fillsthe intake pipe 20 and flows into the channel" I2. owever, when the pump is located a considerable distance above-the level the automatic introduction of priming liquid to the pump channel or buckets, so that each time the pump is started a supply, of liquid is supplied to the pump from an external source. Other methods of priming involve the retention of a quantity of liquid in the pump at all times, d

=liquid apparently fiects a seal between the ima at the top of the casing I require that the bottom of the slot 22 be closed, as indicated at 22, in

upon starting the pump this quantity entrains gas and the mixture is thrown through the outlet IB by the force of'the impeller, after which the liquid is separated from the gas and returned to the pump channel to be again mixed with 5 more gas, and the operation repeated until all of the gas is evacuated from the intake pipe 20 by the recirculation of this quantity of liquid a plurality oi. times.

According to the present invention it is proposed to effect a seal around the impeller in the region of the stop 22, so that air or gas moving through the pressure developing channel I2 is directed through the outlet I5 and is not permitted to flow across the stop to the inlet I4. I propose to establish this seal by means of a small quantity of liquid. To accomplish this I provide a small depression or recess in the stop 22 of each of the rings III and II. Desirably, this depression or recess may be in the form of a slot 22. Each of these slots preferably has its longitudinal axis extending in a radial direction with respect to the axis of rotation of the impeller I. These slots-face opposite sides of the impeller I at the peripheral margins there- 25 of, and are, accordingly, open to the buckets 2. One side wall 2| of each of the slots 20 is thus disposedin parallel relation with the webs 4 as the latter pass the slot upon rotation of the impeller I. As shown in Fig. 4,.it is not required that the 'slots be of great depth, and they may be relatively shallow. One. end 22 of the slot 20 opens into the pressure developing channel I2 ahead of the outlet II and in the region of the stop 22. Upon rotation of the impeller I,

after a period of idleness in which the pump has lost its prime, 9. small amount of the liquid bein pumped, and which was retained in the chann' 1 I2 from a previous pumping operation, is carried by the buckets 2 and enters the slot 22.- This I2 by the buckets '2 is directed through the outlet- IS in a continuous manner until the intake pipe 20 is evacuated and the liquid being pumped flows into the channel through the inlet II an the priming of the pump is complete.

' Pumps which have the discharge passage I8 through the channel I2. Since the amount of so liquid required in the slot 22 is relatively small with respect to the amount retained in the channel I2 from a previous pumping operation, it rarely occurs that there isinsui'hcient liquid to keep the slot 22 supplied until the priming is complete. a v

.The length of the slot 22 may be varied somewhat. but'it is preferable that the side wall 2| beat least as long as the buckets 2. I

In Fig". 6 is illustrated a modified 'construction in which the seal is' elected bye recess or cavity 22 which is formed in the stop 22 radially inward from the portion". 21 of the rib 22. This cavity ummy has a lensth equivalent to that of the length of the bucketstso that one 15 presents a shoulder whereby a seal in the region of the stop 23 is aflorded. Accordingly, although the positions of the side wall 3! of the slot or the side 38 of the cavity may be varied so that they lie in planes at different angles with respect to the plane of rotation of the impeller I and in directions other than radial from the axis of rotation of the impeller, such departures from the preferred position indicated in the drawings render them less effective to provide a self-priming action in the pump.

The cavity 35 has been found to function when isolated from the channel l2. Such liquid as it requires to establish a seal between the stop 23 and impeller i is apparently furnished by the buckets 2 which give up a small quantity of liquid, if needed, as they pass the cavity. However, it has been found preferable to provide a passage 31 extending from the cavity 35 to the channel i2, so that the cavity may receive such small quantities of liquid as are needed directly from the channel in a manner similar to that of the slot 30 which receives the liquid directly from the channel I2 through the open end 32.

In Fig. 8 is illustrated another embodiment of the invention, in which a triangular-shaped recess is formed in the portion of the stop 23 adjacent the end of the channel it next to the outlet l5. This recess has a wall 4| disposed radially with respect to the axis of rotation of the impeller I to present an effective shoulder lying in a plane substantially normal to the plane of rotation of the impeller. This shoulder or wall, like the side 36 of the cavity 35 and the wall 3| of the slot 30, causes liquid entrapped thereby to seal the clearance between the impeller i and the stop 23, thus directing air or gas through the outlet l5. Wall 42 defines the bottom of the recess 40 and prevents liquid flowing by gravity into the interior of the pump chamber 6.

v The various means for effecting a liquid seal between the impellerand stop, which are illustrated in Figs. 1 through 9, may be used with pumps of the type indicated in Figs. 1 and 2. On

account of the inlet H and outlet l5 beingdisposed at the top, a quantity of the liquid being pumped is retained inthe channel I! each time the pump is stopped, so that there is sufficient liquid to fiow into the slot or recess and effect the desired seal upon restarting the-pump in operation.

In Figs. 10 through 13 is illustrated an application of the invention to a rotary pump, .in which both the intake pipe 28 and discharge pipe 2| are connected to bells or boxes It and 65, respectively, at the bottom of the pump casing l.

A pair of pump rings 48 and 41, similar to the rings HI and H, are received in the pumpchamher 3 between the casing I and cover plate- 8 and define the circumferential pressure developing channel l2, previously described. Fluid enters through the inlet box 44 and divides to flow through branches 3 and 43 of the intake passage.

, These branches are each continuous from edge 50 of the dividing wall in the intake passage and .extend on opposite sides of the outlet ii of the minate at the inlet it, each communicating with one side of the channel l2. Accordingly, liquid entering the inlet bell l4 divides and. flows on opposite sides of the outlet [5, then is commingled at the inlet H of the pressure developing channel to fiow through the channel and finally through the outlet Hi. This outlet is continuous with a discharge passage 5| extending through the outlet bell 45. This pump operates similarly to the top inlet and outlet type illustrated in Figs. 1 and 2. The stop 23, with which each of the

rings

46 and 41 is provided, corresponds to the stop indicated by the same numeral in the preceding figures, and closely surrounds the periphery of the impeller l with a running fit, so that fluid is directed into the outlet l5 and discharge M. The slots'3ll formed'in thestops of the rings 46 and d? are like the slots previously described and function in a similar manner to give the pump self-priming characteristics.

On account of the pressure developing channel being disposed above the inlet l4 and outlet l5, liquid would normally flow out of the channel during a period of inactivity and none would be retained to be received in the slot 30 and effect the desired seal. Accordingly, when utilizing pumps of the character illustrated in Figs. 10 and 11, the intake pipe 20 and discharge pipe 2! are tween the impeller and stops 23. Preferably, the

center lines of the intake and discharge pipes are well above the center line of thepump rotor, as indicated in the partially diagrammatic illustration of Fig. 13. In this case the rotor or impeller i is. more than half submerged and an adequate quantity of liquid is retained in the pump for self-priming.

Figs. 14 and 15 illustrate a modification of the slot 3|] which may be applied to pumps having a bottom outletlike that illustrated in Figs. 10 and 11. In this modification a slot 68 is formed in the stop 23 of each of the pump rings and is continuous through the sealing rib 24. It may be desirable to provide this type of slot because of the increased ease with which the slot may be formed, for example, asby a milling operation on the otherwise completed ring, and for incidental advantages in draining the interior of the pump chamber 3. On account ofthe discharge passage ii and outlet I! of the pump being at the bottom of the channel I! the liquid trapped in the slot 58 does not tend to fiow radiwhich would be present with the top outlet, is not experienced. a, i

The slot 53 extends radially with respect to the axis of the impellerfso that one side, 51', is, in effect, a shoulder which is disposed in a plane substantially normal to the plane ofthe impeller.

An opening 58 atone end of each'of the slots 58 communicates with the pressure developing channel l2 to receive a small amount of liquid directly therefrom and admit the liquid into the slot 56 where it forms a seal with the rotor or impeller I to prevent continuous circulation of gas or air through the channel 12 and effect an evacuation of the intake pipe 20. Like the slot 30, the slot 56 need be of only relatively small depth and width. For example, the recesses or depressions may be deep, but preferably they are somewhat deeper, such as although they may be of greater depth.

An advantageous location for the slots is in that portion of the stop 23 which defines the curvature of the channel l2, where the latter is in the nature of a throat leading into the outlet l5. As shown in the drawings, the sides 3|. and ST of the slots terminate at the end of the portion 21 of the rib 25 defimng the outlet l5.

Figs. 16 and-17 illustrate a modification of the invention for application to the pump illustrated in Figs. 10 and 11, which corresponds to the modification of Fig. 8 for the pump shown in Figs. 1 and 2. A substantially triangular shaped recess or depression 60 is formed in the stops of each of the

rings

46 and 41, and one wall 6| thereof is disposed radially with respect to the axis of rotation of the impeller, and substantially normal to the impeller rotational plane. The other wall 82 of the recess may be formed as a continuation of the definingwall of the channel II. The recess 60 may also be relatively shallow, as illustrated in Fig. 1'7, to entrap only a small quantity of liquid, so that the latter may effect a seal with the impeller during the priming of the pump. The third side of the triangular recess is open to the pump channel I! to receive liquid directly therefrom.

The embodiments of the invention illustrated in the drawings may be variously modified and altered to effect a liquid seal across the stop between the outlet and inlet of the pressure developing channel. Pumps equipped with the self-priming means of the present invention have numerous advantageous operating characteristics. In addition to quickly and reliably priming the pump upon actuation after a period of inactivity, onlya minimum amount of liquid need be retained in the pump or associated parts to effect the priming action. Furthermore, there are no supplementary parts or fixtures applied to the pump, and pumps already on the market may be equipped with the means of the present invention to render them self-priming at a small cost.

Various modifications of the invention, which readily occur from a study of the foregoing disclosure and the illustrations of the drawings, are contemplated and intended to be included within the scope of the appended claims.

What I claim is:

1. In a pump, a casing, a rotary impeller in the casing, buckets on the impeller, an annular channel formed in the casing and arranged to receive the impeller buckets, an inlet and an outlet for the channel, a stop between the inlet and the outlet and a recess of relatively small volumetric capacity formed in the stop at .one side of the path of the buckets adjacent the outlet and opening solely into the channel, said recess arranged to receive liquid solely from the channel and to trap said received liquid at said side of the path 01 the buckets to prevent gas being carried through the channel beyond the outlet.

2. In a pump, a casing, a rotary impeller in the casing, buckets on the impeller, an annular channel formed in the casing and arranged to receive the impeller buckets, an inlet and an outlet for the channel, a stop closely surrounding the impeller between the inlet and the outlet, and a recess of relatively small volumetrid capacity formed in the stop and opening solely to the channel and through the stop only to receive liquid directly from the channel and effect a seal between the stop and the impeller.

3. In a pump, a casing, a rotary impeller in the casing, buckets on the impeller, an annular channel formed in the casing and arranged to receive the impeller buckets, said channel having a pressure developing portion, an inlet and an outlet for said pressure developing portion of the channel, a stop closely surrounding the impeller to define the portion of the channel between the inlet and the outlet, a recess of relatively small volumetric capacity formed in the stop and opening solely to the channel through the stop only, and a passageway formed in the stop and connecting the recess with the pressure developing portion of the channel to conduct liquid directly from the channel to the recess for eflecting a seal between the stop and the impeller.

4. In a pump, a casing, a rotary impeller in the casin buckets on the impeller, an annular channel formed in the casing and having an inlet and an outlet, said channel and impeller arranged for progressive movement of the buckets through the channel, a stop closely surrounding the impeller periphery between the outlet and the inlet of the channel, said stop having opposed faces across which the impeller buckets pass in moving through the stop, and recesses of relatively v small volumetric capacity formed in said faces,

said recesses communicating solely with the channel and through the stop only to receive liquid directly therefrom and to trap the received liquid to eflect a seal between the impeller and the stop.

' 5. In a pump, a casing, a rotary impeller in the casing, buckets on the impeller, an annular channel formed in the casing and arranged to receive the impeller buckets, an inlet and an outlet for the channel, a stop closely surrounding the impeller between the inlet and the outlet, said stop having a face across which the impeller buckets pass in moving from the outlet to the inlet of the channel, and an elongated slot of relatively small volumetric capacity formed in said face and positioned to be traversed by the buckets moving through the stop, said slot having an effective length substantially equal to the radial depth of the buckets and arranged to receive liquid solely and directly from the channel to effect a seal with the impeller.

6. In a pump, a casing, a rotary impeller in the casing, buckets on the impeller, an annular channel formed in the casing and arranged to receive the impeller buckets, an inlet and an outlet for the channel, a stop between the inlet and the outlet, a recess of relatively small volumetric capacity formed in the stop adjacent the outlet and opening solely into the channel and through the stop only to receive liquid directly from the channel and to trap the same to prevent'gas being carried through the channel beyond the outlet, and liquid passages communieating with the inlet and outlet through the easing, said passages having portions above the level of the bottom of the channel so as to retain a sumcient quantity of liquid in the channel when the pump is inactive to substantially immerse the buckets therein at the bottom of the channel upon rotation of the impeller.

'7. In a pump, a casing, a rotary impeller in the casing, buckets on the impeller, an annular channel formed in the casing and arranged to receive the impeller buckets, an inlet and an outlet ior the channel, a stop between the inlet and the outlet and a recess of relatively small volumetric capacity formed in the stop adjacent the outlet and opening solely into the channel and through the stop only, one side of said recess forming a shoulder disposed radially with respect to the axis of the impeller and said shoulder having an efiective length at least substantially equal to the radial depth of the buckets, said recess arranged to receive liquid di-.

rectly from the channel, whereby the received liquid eflects a seal between the impeller an the shoulder of the recess.

8. In a pump, a casing, a rotary impeller in the casing, buckets on, the impeller, an annular channel formed in the casing and arranged to receive the impeller buckets, said channel having a pressure developing portion and a sealing portion, an inlet and an outlet for said pressure developing portion of-the channel, a stop closely surrounding the impeller between the inlet and the outlet and having a running fit therewith to define said sealing portion of the channel, and a narrow slot of relatively small volumetric capacity formed in the stop and open to the sides of the impeller buckets, the longitudinal axis of the slot being substantially radial with respect to the axis oithe impeller and the'slot opening at one end into the pressure developing portion of the channel adjacent the outletto receive liquid directly therefrom, said slot arranged to receive liquid solely from the channel buckets, said channel having a pressure developing portion, an inlet and an outlet formed in the casing and communicating with the pressure developing portion of the channel at opposite ends thereof, a stop closely surrounding the impeller between the inlet and the outlet and having a running fit with the impeller, said .stop having opposed wall portions between which the impeller buckets pass during rotation of the impeller. and a recess of relatively small volumetric capacity formed in each of said wall por tions and opening solely into the channel and through the stop only toward the path of the buckets, said recesses being opposite and opening toward one-another and each having a radial length atleast substantially equalto that of the buckets, and the recesses arranged to receive liquid directly and solely from the channel alone, to trap saidliquidand eilect a seal therewith between the said walls of the stop and the inipeller.

HAROLD NEIBERT.