US2179858A - Rotary pump - Google Patents

Description

Nov. 14, 1939. 1 b, MURPHY 2,179,858

ROTARY PUMP Filed June 24, 1937 m5 MMM TTORNEY' Patented Nov. 14, 1939 UNITED "STATES PATENT OFI-lcs ROTARY PUMP Daniel Murphy, New Castle, Pa.

y pplicatlon June 24, 1937, Serial No. 150,017

i 2 Claims.

clusively, adapted for pumps employed in movl ing heavy, viscous'iiuids, such as the slip used in the manufacture of certain articles of chinaware and pottery. v

'I'he object of the invention is to/providean improved rotarypump which will not become gasbound-a pump which automatically` primes itself when it isset in. operation-and a pump which may be readily inspected and cleaned while in service.

Infthe accompanying drawing a pump, embodying the invention in exemplary way, is illustrated partly in vertical section and partly in side elevation.

The pump consists in a body I and a coverplate 2, secured together by bolts 3, and forming an involute :pump-:chamber 4 of usual sort. A shaft 5 supports a vaned impeller 6 in the chamber 4. Within a cylindrical portion la of the pump-body I, the shaft is supported in a bearing of the structure particularly described and claimed in my co-pendng patent application, Serial No. 138,806, iiled April 24, 1937, now vPatent No. 2,128,496, dated vAugust 30, 1938, the shaft extending through and projecting from such bearing (as indicated at 5a), is connected to a motor or other suitable driving means (not shown).

The impeller 6 may be of known construction, including a discular body portion 6a carrying a plurality of vanes 6b, but advantageously it is of the reiined construction illustrated and described in patent application Serial No.-144,136, iiled by me on May 22, 1937, now Patent No. 2,165,808, dated vJuly 11, 1939. The pump-body includes an inlet passage 1, vextending from above the pumpchamber 4 downward and opening centrally of the group of impeller-venes Bb'through the side wall of such chamber. And in usual way an outlet passage 8 opens tangentially through the peripheral wall of the chamber, and extends upward from the impeller. During pump operation, the rapidly rotating impeller operates to draw liquid inward through passage 1 into the usual spaces between the vanes of the impeller,

whence centrifugal force urges the liquid radially outward and into the outlet passage 8.

.The right-hand edges.oi the impeller varies` right-hand side wall of the chamber 4. In service there is wear between these relatively moving parts. As described in my above-noted Patent No. 2,128,496, I embody in the said side wall of ,the impeller-chamber a wearing ring 2l and the central opening 1a of such ring provides the essential communication between the inlet passage 1 and the chamber 4. Advantageously, the ring 2| is made of material softer than the vanes of the impeller-speciflcally; the impeller being 10 formed of cast iron or steel, the ring is made of brass or bronze. As to the matter of axialadjustment of the impeller and the replacement of worm parts, reference is a'gain made to said Patent No. 2,128,496. 15

The liquid entering the pump is drawn .upward through a conduit 3l from a source of supply. Aboye the conduit 34, and at higher elevation than the impellerchamber 4, I provide a chamber 33 including a check-valve 32 adapted to en- 20 gage a seat`43. The chamber 33 is closed from above by a cover 30,` held in place by means of a removable clamp 29, and the cover carries a spider 36 that extends downward into the checkvalve chamber arid loosely engages the upper end 25 'of astem 35 integral with the check-valve. The wall of the chamber 33 is formed with plurality lof vertical ribs 34; and these ribs, together with the sliding engagement of the stem 35 in spider 36, provide effective means for guiding the valve 32 in its vertical movement to and from the seat 43.

The inlet'passage 1 opens laterally into the cylinder 33, and extends downward therefrom to the impeller-chamber 4. The discharge line or 35 passage 8 includes a relatively large receiver chamber'31, and it will be perceived that the receiver ichamber is located at higher elevation than the impeller-chamber 4; The check-valve chamber is assembled with the receiver chamber in a flange-union 28, and the assemblyv of these two chambersis removable as a unit from the pump-body. lf2. The detachable union is indicated by the reference numerals 21 and 39. The valueof this "structural feature will later appear. 45

On the pump side ofthe check-valve 32, and at a point above such check-valve, a by-pass 38 of relatively small cross section opensthrough the side Wall of .the check-valve chamber 3 3. This bylpass extends to, and opens into, the bot-v 50 tom region of receiver chamber 31. When the impeller is set in rotation and comes up to speed, uid is drawn upward through conduit .3| ;the upwardly ilowing uid liftsand holds the valve 32 from its seat, and or other gas which 55 is trapped above the valve, or riseswith the liquid in conduit 3|, is by-passed under its own buoyancy through vent 38 into the receiver chamber 31, it being understood that the inlet and outlet passages 1 and 8 are normally filled with liquid, whether the pump be idle or running, to a level substantially above the impeller-chamber 4. It will be noted that in the circumferential intervals between the ribs 34 `there is clearance between the wall of the chamber 33 and the periphery of the check-valve 32, and, by virtue of such clearance, the rise of the check-valve to a position against the lower end of the spider 36 does not prevent the escape of gas between the inletl passage 3|, 1.and the vent 38. The gas rises through the clearance between the ribs, and escapes through vent 38. When the pump attains its normal operating speed, the entrained gas is drawn into the impeller-chamber and discharged with the liquid being pumped.

In the Kinstallation illustrated in this case, the pump is organized above the source of liquid being pumped, and it is in such installations, as those in the art Well know, that rotary pumps tend to become gas bound and require priming. A pump of the construction described herein need never be primed, once it has been installed and operated, and, additionally, the pump will never become gas bound.

In' case the pump be arranged below the level of the source of liquid, these particular problems do not exist, and the check-valve structure and receiver-chamber are not needed. In adapting the pump to either of these conditions of service, the check-valve and receiver-chamber are, as

already mentioned, provided in a unitary structure that may be readily detached from the pump proper, by removing the bolts 39. That is, the unit 33, 31 may be readily assembled with or removed from the pump, to meet one condition of service or the other.

It is also noteworthy that, by virtue of my structure, the pump proper and bearing unit may be readily removed from an installation in the field, and a new unit quickly installed. Thus, if there should be bearing or impeller failure, the time lost is only a matter 'of a few minutes.

It is important that the check- valve assembly 33, 32 and by-pass 33 may be readily inspected and cleaned. To such end the cover 30 and check-valve 32 are adapted to be removed. It is merely necessary to remove the clamp 29, lift the cover 30, and withdraw the valve 32, it being noted that the upper end of the valve-stem 35 is accessible to the grasp of the attendant. In the wall of the check-valve chamber, opposite to and in line with the by-pass 38, I provide a plug 48. By removing this plug, a wire or other suitable instrument may be used to clean the by-pass.

I have found that to obtain best operation, the size (cross-section) of the by-pass 38, while being of relatively small cross-sectional area in any case, must be minutely determined for each fied of service. When pumping heavy liquids, the by-pass should be larger than when pumping light liquids. In order to obtain the desired variability in the otherwise xed size of the bypass 38, I provide-in the piane of meeting of the flanges 28 (either in the body of the receiverchamber 31 or in the body of the check-valve chamber 33) a block 4I, including an orice 42 of proper size.

To the ends in view it is important to note in addition to what already has been said that the check-valve 32 is arranged within a cylindrical chamber 33; that the by-pass is f relatively small cross-sectional area; that the bypass, extending from the receiver-chamber 31, opens in the cylindrical wall of the check-valve chamber at a point above the check-valve therein and above the mouth of the inlet passage 1 that opens into the check-valve chamberythat the by-pass is normally always open, so that gas may iiow into the receiver-chamber, or liquid may flow from the receiver-chamber into the inlet passage 1 of the pump; and that the cylindrical wall of the check-valve chamber continues upward a substantial interval above the point where the by-pass opens into the check-valve chamber.

By virtue of my construction the check-valve chamber may be opened, the check-valve removed and cleaned, and the by-pass cleansed, without chamber, and a check-valve unit including an inlet and an outlet, a check-valve in the line of ilow between such inlet and outlet, a by-pass opening Ainto said check-valve unit above the check-valve therein; and a removable closure arranged to give access to said by-pass for cleaning While the pump is in operation; the improvement herein described in the above-delined organization that consists in a detachable member interconnecting the pump and the check-valve unit, said member including a passageway con- .necting said inlet passage of the pump to said outlet of the check-valve unit, said member including a passageway leading from said outlet passage to the pump, and a passage leading from the by-pass from the check-valve chamber to said last-mentioned passageway.

2. In a pump including a pump body, an impeller chamber in said body, a rotary impeller in said chamber, an inlet passage leading to the chamber, an outlet passage leading from the chamber, and a check-valve unit including an inlet and an outlet, a check-valve in the line of flow between such inlet and outlet', and a bypass opening into said check-valve unit above the check-valve therein; the herein described improvement in the above-defined organization that consists in a detachable receiver-unit interconnecting the pump and the check-valve unit, said receiver-unit including a passageway connecting said inlet passage of the pump to said outlet of the check-valve unit, and a passageway leading from said outlet passage of the pump, together with a passageway establishing communication between the last-mentioned passageway and the by-pass of said check-valve unit.

DANIEL MURPHY.

l CERTIFICATE OF CORRECTION. Patent No. 2,179,858. i I November 111, 1959.

" l DANELMURPHY.

It is hereby certified that error appears in the printed specification of the abovre numbered patent requiring correction as follows: Page 2, second column, line b9, claml, for the words "passage to'l read passage of; and that the said Letters Patent should be readwith this correction therein' that thel same may conform to the record of' the case in the Patent Office.

Signed and sealed this 12th Re* of'y December, A. D. 1939.

Henry v\an Arslale,` (Se-al) Acting Commissioner of Patents.

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