US2175997A

US2175997A - Centrifugal pump

Info

Publication number: US2175997A
Application number: US165560A
Authority: US
Inventors: Arthur C Saxe
Original assignee: Jaeger Machine Co
Current assignee: Jaeger Machine Co
Priority date: 1937-09-24
Filing date: 1937-09-24
Publication date: 1939-10-10
Anticipated expiration: 1956-10-10

Description

Oct. '10, 1939'.

A. c. SAXE CENTRIFUGAL PUMP Filed Sept. 24, 1937 2 Sheets-Sheet 1 IIIII/ n 1 V I u Q 7 V v a 0 o a u I I m u 1 M INVENTOIR. J Arfhur C. 50x6:v W 1- ATTORNEYS.

0x10, 1939. A. c. SAXE 7 .9 7

" CENTRIFUGAL PUMP Filed Sept. 24. 19:57 2 Sheets-Sheet 2 INVENTOR.

A TTORNEYS.

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Patented Oct. 10, 1939 CENTRIFUGAL r Arthur 0. Saxe, Columbus, Ohio, assignor to The Jaeger Machine Company, flclumbua, Ohio, a

corporation of Ohio Application September 24, 1937, Serial No..,165,560

2 Claims.

Myinvention relates to centrifugal pumps. It has to do, more particularly, with centrifugal pumping apparatus embodying a plurality of co-= operating pumping units.

One of the objects of my invention is to provide centrifugal pumping apparatus which embodies a plurality of pumping units, the apparatus being of such a nature that it may be used as a multi-stage pump for obtaining high discharge pressures or may be readily converted into a high capacity pumping apparatus for obtaining high capacity discharge at normal discharge pressures. Another object of my invention is to provide centrifugal pumping apparatus of the type indicated which is self-priming both when used as a multi-stage pump and when used as a high capacity pump.

Another object of my invention is to provide pumping apparatus of the type indicated which is very efficient in operation but which is extremely simple.

Another object of my invention is to provide centrifugal pumping apparatus of the type indicated which is of very rugged construction and upon which the upkeep will be reduced to a minimum.

In the following description I will refer to my centrifugal pumping apparatus as being a dualpump but it is to be understood that my invention is not limited to a combination of two pumping units but may comprise any number of cooperating pumping units.

In its preferred form my invention contemplates the provision of two cooperating centrifugal pumps. These two centrifugal pumps are driven by the same power unit. They are so arranged that they may be used as a two-stage pump for obtaining high discharge pressures. When used for this purpose, the two pumping units are operated in what I will call tandem or series. That is, the discharge of one pumping unit is connected to the inlet of the other pump= ing unit.' However, the pumping apparatus is also so arranged that it may be quickly and easily converted into a pumping apparatus for obtaining dual capacity at normal discharge pressure. When converted into a dual capacity pump, the two units operate in what I will call parallel. When operating in this manner, the discharge of the first unit is not connected to the inlet of the second pumping unit. My centrifugal pumping apparatus is so constructed that it is self-priming when used as a two-stage pump or when used as a dual capacity pump.

The preferred embodiment of my invention is illustrated in the accompanying drawings wherein similar characters of reference designate corresponding parts and therein:

Figure 1 is a longitudinal section taken through pumping apparatus constructed in accordance 6 with my invention and comprising two cooperating pumping units, one unit only being provided with self-priming mechanism and a suitable priming connection to the other pumping unit being provided.

Figure 2 is a perspective view, partly broken away, of the pumping apparatus illustrated in Figured.

Figure 3 is a perspective view, similar to Figure 2, but taken at a different angle, the pumping units being shown connected in tandem or series.

Figure 4 is a view similar to Figure 3 but showing the pumping units operating in parallel.

With reference to the drawings and particularly to Figures 1 and 2 I have illustrated my invention as comprising two centrifugal pumping units. In Figures 1, 2 and 3, the two pumping units are connected in such a manner that the pumping apparatus may be employed as a two- 'stage pump.

The pumping apparatus comprises a power unit I, a centrifugal pump 2 and a self-priming centrifugal pump 3. All of these units are mounted in cooperating relationship on a suitable base 4. The power unit I may be of any suitable type, for example, an internal combustion engine or an electric motor.

The self-priming pumping unit 3 is preferably practically identical with the centrifugal pump structure disclosed in my Patent No. 2,061,521, which issued November 17, 1936. This pumping unit 3 is bolted to the base 4 as at 5. It'comprises a pump casing which is preferably of the form illustrated in the drawings. This casing is provided at one side adjacent to the top thereof with an intake port 8 to which a suction line Il may be suitably connected. The intake port 6 is under the control of a hinged check valve 8 which will permit entrance of fluid into the pump casing but will prevent drainage of water there from through the inlet port 6. A discharge outlet 9 is provided in the top of the pump casing. An opening it is provided in the top of the pump casing by means of which this casing may be initially filled with water.

An impeller chamber ii is formed within the casing at the side opposite the inlet port 5. This impeller chamber is of volute form and is eccentrlcally. disposed within the casing. It is of considerably less width than the casing and is located more closely adjacent to the base than to the top of the casing. The impeller chamber is provided with a discharge outlet |2 which is located at the bottom of the priming liquid com partment which is formed within the casing. Water discharged from the impeller casing will pass upwardly through the priming compartment to one side of the impeller chamber and to the discharge outlet 9.

The priming liquid compartment may be generally designated I3. A portion of it is disposed above the impeller chamber H and a suction chamber l4 and a portion of it is also formed below the suction chamber. The suction chamber is disposed between the side wall of the pump casing and the impeller chamber An opening I5 is provided in the dividing wall between the suction chamber l4 and the impeller chamber II. This opening I5 is comparatively large and is disposed at the axis of the impeller I6 which rotates in the impeller chamber. In the bottom of the suction chamber a priming port I1 is formed. An elbow member I8 is mounted within the suction chamber and over the priming port. This elbow member I6 is adapted to receive water which passes upwardly through the primary port from the priming. compartment and-to direct this water in a diverging stream through the opening l5 in the wall of the impeller chamber.

The priming port I! is under the control of a hinged valve plate l9 which is mounted below the priming port and is located in the priming compartment. This valve has an operating finger 20 which projects into the path of flow of liquid discharged from the impeller chamber II. This valve is identical with that disclosed in my prior patent and will operate in exactly the same manner described in said patent. In other words, it will hang open until the liquid discharged from the impeller chamber and striking the finger 20 has a predetermined velocity head and will then close and stay closed until the velocity head of said liquid falls below the predetermined amount. The valve will quickly open when the pump needs priming and will close when the ,priming is completed. It is so arranged that the velocity head of-liquid discharged from the impeller chamber will initiate the closing action and unbalanced hydrostatic pressure and vacuum created by the impeller will aid in closing the valve and keeping it closed.

During the priming action, the valve will be open. The priming compartment will be filled with water and the impeller will be rotated. The impeller will draw water upwardly through the priming port l1 and through opening l5. It will discharge it from the impeller chamber into the priming compartment. This circulation of -priming water will continue until the priming of the pump is completed. During this circulation of priming water, the air will be withdrawn from the suction chamber l4 and will be carried into the impeller chamber by the-stream of water entering through the opening IS. The air and the water mixture will bedischarged from the priming impeller chamber into the priming compartment and the air will risefito the top of the compartment and pass outwardly through the discharge outlet 3. The circulation of priming water will continue until substantially all the air has been exhausted from'the suction chamber I4 and the suction line 1. At this time the valve l9 will close and will remain closed until the pump again needs priming.

. discharge line" which has one end bolted to the v The impeller I6 is carried on one end of a shaft 2| The impeller preferably comprises a plurality of widely spaced blades of the shape illustrated in my prior patent. The shaft 2| extends through the pumping unit 2 and is driven by the power unit I. This shaft also carries the impeller 22 of the pumping unit 2.

The pumping unit 2 comprises a centrifugal pump but is not provided with priming mechanism of the type provided in the unit 3. This pump comprises a volute casing 23 in which the impeller 22 rotates. 24 and a discharge outlet 25.

A casting 26 is provided between the pumping units 2 and 3. This casting is bolted to the base 4 as at 21. It is provided with a portion 28 which forms one wall of the casing of the unit 3 and which is bolted to the unit 3 as at 29. It is also provided with a portion 30 which forms one wall of the casing of the unit 2 and is bolted to said casing. as at 3|. This casting serves to rigidly secure the units 2 and 3 together and to the base 4. Furthermore, it permanently aligns these two pumping units with each other. The casting 26 is provided with a centrally disposed sleeve 32 which serves as a bearing for the shaft 2|. A fluid seal 33 is provided in the sleeve 32 in surrounding relationship to the shaft 2|. This seal is located between the two pumping units and is adapted to prevent air from passing from the pumping unit 2 along the shaft 2| and into pumping unit 3.

The seal 33 comprises compressible sealing material which is preferably in the form of small solid particles and which are placed in the chamber indicated surrounding the shaft 2| and within the sleeve 32. This sealing material may be compressed by a bolt 34 which extends into said chamber and will contact with the sealing material.

On the opposite side of the pumping unit 2, between said unit and the power unit I a casting 35 is disposed. The inlet 24 and the passageway 36 leading into center of the pump casing 23 are formed in this casting 35. This casting has one end bolted to the casing 23 as at 31 and the other end bolted to the power unit as at 38. Thus the casting serves to align the pumping unit 2 with the power unit I. The shaft 2| passes through chamber 36 and through bearings 39 and 40 provided in the casting 35. A packing gland il is provided in bearing 39. Suitable automatic wear take-up means indicated by the numeral 42 in Figure 2 may be provided for compressing the packing of the gland unit 4|.

It will be apparent that when the shaft 2| is rotated by the power unit, the impellers 22 and I6 of the pumping units 2 and '3 will be rotated.

It will be noted from the drawings, particu larly from Figure 3 that I provide a line-or conduit 43 running from the pumping unit 3 to the pumping unit 2. This line is connected to the inletpassageway 36 of the unit 2 as at 44 and its opposite end is connected to the suction chamber ll of the unit 3 as at 45. However, the line l3 may be connected to the casing of unit 2 at any desired point. A valve 46 is provided for controlling flow of fluid through this line.

When the pumping apparatus is to be used as a two-stage pump for obtaining high discharge It is provided with an inlet 4 pressures, the two units are connected in tandem discharge outlet 3 of the unit 3 and its other end bolted to the inlet 24 of the unit 2.

The discharge line 41 is provided with an air escape valve 48 which may be opened during the priming of the pumping unit 3 to facilitate the escape of air from the apparatus. However, it is not necessary to have this valve inasmuch as the air will utimately escape through the pumping unit 2.

When the pump is being used as a two-stage pump the valve 46 in the line 43 will be closed. The power unit will be started in operation so that it will rotate the shaft 2| and, consequently,

the impellers l6 and 22 of the units 3 and 2. The

priming compartment l3 will be full of liquid. The impeller IE will recirculate the water through the priming portuntil the pumping unit 3 is primed. Then this pumping unit 3 will start to pump water through the discharge line 41 andinto the pumping unit'2. This water will force all the air from the pumping unit 2 through a discharge line 49 which is connected to the discharge outlet 25 of the pumping unit'2. Thus the pumping unit 2 will beprimed and both pumping units will then function to produce a high discharge pressure of the liquid discharged through the line 49. It will be apparent that the pumping unit 3 is self-priming and that this unit when i it is primed will prime the other unit too.

When this pumping apparatus is to be used as a double capacity pump, the apparatus should be arranged in the manner illustrated in Figure 4. The discharge line 41 is disconnected from the pumping unit 2. To the inlet of the pumping unit 2 a suction line is connected. When the apparatus is arranged in this manner water will be drawn directly into the pumping units 2 and 3 through the suction lines .50 and 1 respectively. It will be discharged directly from the pumping units 2 and 3 through the

discharge line

49 and 41 respectively.

In order to prime the pumps when they are connected in this manner, the valve 46 should preferably be closed during the priming of the pump 3. However, as soon. as the pump 3 is primed, the valve 46 should be opened. This will cause the water passing through the suction chamber l4 of pumping unit -3 to withdraw the air from the line 43 and, consequently, from the pumping unit 2. Furthermore, with this arrangement the pumping unit 3 will always maintain the pumping unit 2 primed. When the apparatus is used in this manner it is necessary to have a check valve Si in the discharge line 49 of pumping unit 2,'in order to prevent air from entering unit 2 through this line during the time the' 'air is being exhausted from this unit by" means of line 43. The line 43 may be connected at any point to the casing of unit 2 since it will withdraw the air from such casing regardless of where it is connected thereto.

double capacity pump.

It will be apparent from the above description that I have provided centrifugal pumping apparatus having a number of advantages. The apparatus is of such a nature that it may be used as a multi-stage pump for obtaining high discharge pressures or may be readily converted into a high capacity pumping apparatus for obtaining high capacity discharge at normal discharge pressures. The apparatus is self-priming both when used as a multi-stage pump and when used as a high capacity pump. It is very eflicient in operation and is extremely simple.

Various objects and advantages will be apparent from the preceding description, the drawings and the following claims.

Having thus described my invention, what I claim is:

1. Pumping apparatus comprising a plurality of centrifugal pumping units, means for operating said pumping units, a self-priming means on one of said units comprising a priming liquid compartment and means permitting automatic recirculation of the liquid contained in said compartment through said pumping unit, and another of said pumping units having no self-priming means, and a priming conduit extending from the suction chamber of said pumping unit which is equipped with the self-priming means to the suction chamber of the pumping unit not so equipped so that the pumping unit having the self-priming means can be used to efiect priming of the pumping unit not so equipped while the pumping units are in parallel by withdrawing air therefrom.

2. Pumping apparatus comprising a plurality of centrifugal pumping units, means for operating said pumping units, a self-priming means on one of said units comprising a priming liquid compartment and means permitting automatic recirculation of the liquid contained in said compartment through said pumping unit, and another of said pumping units having no self-priming means, a priming conduit extending from the suction chamber of said first-named pumping unit to the suction chamber of said last-named pumping unit so that. the pumping unit having the self-priming means can be used to eflect priming of the pumping unit not so equipped while the pumping units are in parallel by the withdrawal of air therefrom, means for rendering said priming conduit ineflective, and means for sealing said pumping units from each other.

ARTHUR C. SAXE.