US2224615A - Priming means for self-priming pumps - Google Patents

Description

Dai 10, 1940- A. c. sTRA-r'roN 2,224,615

PRIMING MEANS FOR SELF-PRIMING FUMPS Filed Jan.4 30, 1959 2 Sheets-Sheet 1 l-JI Dec. 10, 1940. A. c. sTRA'rTON PRIMING MEANS FOR SELF-PRIMING PUMPS I Filed aan. 50, 1959 2 Shee-gs-Sheet 2 nunmllllllll RNEY Patented Dec. 10, 1940 Albert c. Stratton, Ridgewood, N. J., signor to Alfred S. Marlow, Ridgewood, N. J.

Application January 30, 1939, Serial No. 253,540

2 claims. (ci. :ws-11a)` My invention relates to improvements in a priming means for self-'priming pumps. It relates more particularly to impeller type pumps. Such pumps are constructed so as to pump and operate at levels higher than the level of the liquid to be pumped. Such pumps must therefore prime themselves without external means` .and do so by automatically exhausting all air and/or gas from the suction line. v

The first object accomplished by my said invention is that it simplifies the present construction of said types of pumps, thus permitting an unusually small pump case and other parts,which make for better portability and low manufacturing costs. A second object is that it exhausts the air from the suction line much more rapidly than is presently accomplished, and thus the pump is put in operation in a minimum amount of time. A third object is that it develops within 2 itself a high vacuum thus enabling the pump to prime itself when operating on unusually deep suction lifts. A fourth object is to enable the pump to prime and to reprime itself automaticala ly, repeatedly, as may be required when the sup- 25 ply to the pump suction is less than the pump capacity. A fifth object is to pump a maximum amount of air during the priming period and also deliver the full capacity of the impeller when pumping. A sixth object is the elimination of 30 adjustable or moving parts other than the pump impeller and its drivingshaft.

My invention applies to all types of suctio pumps of the centrifugal or impeller type and may. supplant the present pumps of said types. It is also applicable to the class of pumps known as Construction pumps as covered by my former patents #2,059,288 and #2,100,365. Said latter class of pumps calls for a high capacity performance, dependability, and light weight for portability.

One form of my invention is illustrated in the accompanying drawings in which Figure 1 shows a longitudinal section through pump unit. Figure I is supported and driven by shaft 21 and rotates within volute I1. volute I1 has a discharge 55 opening I 8 lconnecting to the interior of pump portion of the pump volute.

housing I0. A case closing flange I9 forms a Slots 22 extend substantially all around the outer periphery of the volute wall and are constructed to be in radial y alignment with clearance 23 at the forward face 24 of impeller I5.4 The .impeller housing v25 has an extended box-shape connection 25' extending to connect with the suction inlet at check valve I3. Impeller I5 is supported and rotated by shaft 21 which may be connected to any convenient power. Shaft 2l is supported on suitablebearings 28 in bearing housing 26. Shaft 21 is sealed at its entrance into end closing iiange I9 by conventional stuiiing box I6.

Figures 3 and 4 illustrate two modifications of my invention. Figure 3 shows'a section of vthe impeller with volute closing case I1. The impeller vane faces 24 have projecting edges 29. Figure 4 shows a section of the impeller with closing case asv one piece abutting directly the cover plate I9 and carrying slots'3I within itself. In all the forms shown it is understood that the slots 22 and 3i can be substituted by port openings of other shapes located in the outer periphery of the volute housing. Furthermore, while for purposes of .construction it is desirable to provide clearance 23 at the front of impeller I5, tests have shown that clearance 2,3 may be provided at the back face of the impeller I5 with slots 22 arranged in alignment with clearance 23.

In the operation casing III is lled through opening 20 with water 'or other liquid so that all of volute I1 is submerged. The impeller I5 is caused to rotate, developing a centrifugal action which causes the liquid in impeller entrance I4 and suction passage I2 to be discharge through volute outlet 18 into chamber 2l of pump housing IIJ. The interior of volute Il having been emptied of liquid the rotating impeller will not permit thel liquid to flow back into volute outlet i8. At this time slots 22 are subject to the pressure of liquid on the outside of the volute I'I, and also a lower pressure of air or gas within volute I8, with a resulting flow of vliquid through slots 22 inward radially toward the clearance 23 at the front of impeller I5. The combined spray action of the liquid flowing inwardly through slots 22 together with the intense spray induced as the radial ow of liquid strikes the spinning face '24 of impeller I5 produces a mixture of air .and/or gas and liquid whichis caught by the rotating impeller I5 andl thrown outward by centrifugal force into volute I1 and discharged through opening I8 of volute I1. This action rapidly exhausts the air and/or gas from entrance I4, and

suction passage I2, and also from the suction hose or piping which may be connected to inlet II, thus creating a partial vacuum Within said passages. As the vacuum increases, due to the continual exhausting of air as just described, liquid will be raised up the suction hose, or pipe' the vane passages 24' of impeller I5, filling the interior of volute I'I. The water and/or liquid filling volute Ilforms a barrier to the inflow of priming liquid through priming slots 22, and as the pump builds up to full discharge pressure,

the flow of liquid inwardly through slots 22 is stopped and reversed by reason of the pressure Within volute I1, resulting' from the velocity of liquid flow imparted by impeller I5 and the liquid ydrafted by the pump through suction inlet I2 is discharged into the interior 2| of pump housing I0, through both slots 22, and volute outlet I8. Simultaneously pressure is built up within pump housing I and liquid is discharged through outlet 20.` The pump, having thus automatically exhausted the air from the suction connection and pump interior, will continue to discharge liquid until air and/or gas is again admitted to the suction connection. Immediately upon the admission of sufficient air and/or gas to cause the liquid passages 24 of impeller I5 and the interior of volute II to be occupied by air and/or gas instead of liquid the pump will temporarily cease discharging and the lower pressure of the air and/or gas within volute I1 causes an inward flow of the liquid within chamber 2I through slots 22 as just described, to reestablish the prime.

This automatic cyle ofY operation to establish the prime will occur whenever the pump is started up, after which the pump will discharge liquid as long as the supply is adequate, or will occur at frequent intervals if the supply is less than the capacity of the pump. l

Referring again to Figure 1 the'faces 24 of impeller 4I5 face the enclosing Wall. 25 with clearance space 23 interposed. It will be seen that when the interior of volute I'I and impeller passages 24 are occupied by air and/or gas, the priming liquid jettied through slots 22 will be free to enter clearance 23,. as before described, and as the total open area of slots 22 is proportioned to permit a ow of liquid substantially less than the capacity of the impeller, the ow inwardly through slots 22 cannot alone fill the vane passages 24 or interior of volute I'I during the priming cycle. However, when all air and/or gas has been exhausted andv the impeller is delivering liquid, wall 25 forms aportion of impeller passage 24' and by reason of the centrifugal action of impeller I5, liquid will flow outwardly in clearance 23. Thus when the pump is discharging there is no appreciable loss of pumping eiilciency. Referring again to Figure 3 the impeller may be provided with the front faces 24 of impeller I5 having projecting edges 29 on the inner periphery to aid in providing a finely divided spray of the liquid entering through slots 22 and flowing through clearance 23 during the priming cycle. This action increases the ability of the pump to exhaust air and/or gas and therefore shorten the time required by the pump to prime automatically.

.livered pump' capacity over systems now in use.

Tests further show that there is a preferred area of the priming slots 22 which must be determined by experiment for each size of pump constructed.

While I have illustrated my invention in different ways and using different materials and means, still I do not intend to limit myself to those particular means, designs, methods or materials, as it is apparent that other means, designs, methods, and materials may be employed for obtaining the same results within the scope of any claim without departing from the scope orspirit of my invention.

I claim:

1. A priming means, for self-priming pumps, as hrein described, comprising an enclosing case, a' volute housing within said enclosing case, an impeller having vanes arranged to rotate within said volute housing, the forward edges of said impeller vanes having portions extending into a clearance space adjacent the forward edge of said impeller vanes, ports in the outer periphery of said volute housing to permit liquid within said enclosing case to be jettied into and across the open passage of said volute, and intosaid clearance to create a nely divided mixture of gas and liquid within said impeller, to effect the priming of said pump.

2. A priming means for self-priming pumps, as herein described, comprising an enclosing casing, a volute housing within said enclosing casing, an -impeller arranged'to rotate Within said volute housing and openings in the outer periphery of said volute housing in alignment with a clearance space between the face of said impeller and said volute housing through which liquid retained within said enclosing casing is sprayed radially into and across the open passage of said volute and into said clearance space for reentry into the impeller passages as a finely divided mixture of gas and liquid.

Images