US2875697A - Sump pump - Google Patents

Description

March 1959 F. o. FERNSTRUM 5,

SUMP PUMP Filed Aug. 5, 1953 2 Sheets-Sheet 2 IN VEN TOR.

United States Patent() SUMP PUMP FrankO. Fernstrum, Grosse Pointe, Mich., assiguor to Marine Products Company, Detroi ,-Mich., a corporation of Michigan Application August 5, 1953, Serial No. 372,503 2 Claims. to]. 103-103 Which is of the maximum simplicity of construction and n which utilizes metal stampings primarily in its construction, witha minimum of castings, so as to reduce its cost of manufacture to the minimum amount and likewise reduce the cost of the expensive materials employed in such castings for such pumps.

Another object i sto provide a sump pump which is constructed in such a manner as to be capable of being shipped knocked-down and assembled in thefield without any special tools, other than a screw driver and optionally a wrench, thereby economizing on space and shipping charges.

Another object is to providea sump pump of the foregoiug character wherein the only machining operations required 'in the stampings and single casting employed are merely drilling and threading certain holes.

, Another object is to employ a sump pump wherein the pump housing or casing and the vertical tubular motor support may be assembled one within the other without the necessity of accurate aligning, such aligning being automatically accomplished by the use of the sense of touch, from the constructionofthe parts.

Another object is to provide ,a sump pump having a screen thereabove with upwardly-facing perforated surfaces, so that the screen may be easily cleaned from above without removing the sump pump from the sump, such as, for example, by theme of a long-handled broom or brush. r V

. Another object is to provide a sump pump wherein the pump inlet ports are so arranged in the pump casing as to be directed at the perforations of the protecting screen, with the result thatwhen the pump ceases operation, the water which has been forced upward into the outlet pipe come apparent during the course of the following description of the accompanying drawings, wherein:

Figure l is a side elevation, mainly in central vertical section, of a sump pump according to one form of the invention, with the central portions of the supporting tube, outlet pipe, drive shaft and float rod omitted for conciseness of showing;

Figure 2 is a horizontal section taken along the line 22 in Figure 1; i p

Figure 3 is a horizontal cross-section taken along the line 3-3 in Figure 1, showing the pump rotor bearing construction; a Figure 4 is a horizontal section taken along the line 4-4 in Figure 1, showing the automatic flooding arrangement for the pump impeller bearing in the event of switch failure; and

flows back downward by gravity and gushes out through these ports and against the screen perforations, automaticallycleaning off the screen.

Another object is to provide a sump pump having a float rod andifioat, the positions of which are adjusted relatively to oneanother by means of spring stops of improved construction and of simple and easy adjustment.

Another object is toprovide a sump pump having a U hearing which is automaticallylubricated by water even if the pump accidentallyremains in operation after it has pumped the water out of the sump to the intended depth, because of a failure of the shut-off switch.

w Another object is to provide a sump pump of the fore- Figure 5 is a fragmentary vertical section taken along the line 5-5 in Figure 1, showing thereturn liquid flow channel for automatic flooding of the impeller bearing upon switch failure. H

Sump pumps are in frequent use for draining basements or other similar sunken areas wherewater is likely to collect, and are ordinarily mounted invertical wells in When the water level rises in the sump, it lifts thefloat,

actuates the switch to close the circuit to the motor, and causes the motor to operate the pump until the water level subsides, causing the float to drop and open the switch, halting the motor. Such previous sump pumps, however, have been subject to numerous defectsand disadvantages. a

For ,yarious reasons, the motor sometimes continues in operation after it has pumped the water down to the desired level, causing burning out of the metallic bearing ordinarily used for the pump impeller. Furthermore, such pumps have usually employed cylindrical protective screens to keep them from being clogged with foreign matter, and since these screens have been located in vertical directions, they have been difiicult to clean from above. Such sump pumps, moreover, have also previously employed expensive bronze castings requiring complicated machining and expensive assembly operations, bronze being used because of its low corrosive properties, with the result that a high quality pump has been expen sive to manufacture and consequently expensive to buy. On the other hand, the cheapening of the pump by using less expensive but corrodible materials is also undesirable because failure of the sump pump in the absence of the owners of the property permits flooding to occur, with consequent damage to the contents of the basement or other area protected by the sump pump. Finally, such pumps have ordinarily been assembled at the factory and shipped in assembled condition, the bulk of the shipment resulting in high shipping charges, particularly to remote locations, such as the Pacific coast. Such prior pumps, however, havenot been constructed in such a Q manner as to enable them to be shipped knocked-down and easily assembled at their destination.

The present invention provides an improved sump pump which eliminates these disadvantages and. defects. The pump is so constructed that only one casting is employed and that is only a small casting comprising the upper half of the pump casing, the lower half being providedby an easily produced stamping. The protective screen is also a stamping, and is arranged with its perforated surface facing upwardly so as to be visible from above and easily accessible for cleaning by means of a broom, mop or long-handled brush. The pump inlet ports are also inclined upwardly with their axes substantially perpendicular to the perforated surface of the screen, so that when the pump ceases operation, the pump outlet pipe acts as a standpipe so that Water previously forced up into the outlet pipe flows back downward under the force of gravity and gushes out through the upwardly-inclined inlet ports and against the perforated surface of the screen, automatically cleaning the screen.

The pump, moreover, is so constructed that the parts may be shipped knocked-down, thereby economizing on shipping space and shipping costs, yet its construction is such that its parts are easily assembled in the field without skilled workmanship and without special tools, only a screw driver and optionally a wrench being required. The pump casing is provided with a pilot counterbore above the threaded socket into which the supporting tube is inserted, so that these parts are automatically aligned with one another during assembly. The strain or shearing elfect ordinarily present at the junction of the threads on the tube and the member into which it is threaded, as occurring in prior pumps and resulting in breakage at the weakened threaded location, is eliminated, since the portion of the tube seated in the pilot bore is unthreaded and is therefore of maximum strength.

Moreover, the sump pump of the present invention employs a pump impeller bearing of elastic deformable material, such as natural or synthetic rubber or mixtures thereof, this bearing having the properties of being lubricated by water and requiring no oil or artificial lubricant. As a consequence, the bearing is automatically lubricated as long as there is water in its vicinity, and the pump is so constructed that water always flows to the bearing through a hollow bore in the pump impeller and through a hollow impeller drive shaft to the bearing, thereby insuring against burning out of the bearing, even if the switch should fail or the motor for any other reason should continue in operation after the water level has been reduced to the point where the pump should have ceased operation.

Referring to the drawings in detail, Figure 1 shows a sump pump, generally designated 10, according to one form of the invention as consisting generally of an elongated supporting tube 12 upon the upper end of which a motor 14 is mounted and upon the lower end of which a pump 16 is also mounted and protected by a screen 18 of novel configuration. The motor 14 is of conventional construction and its details are outside the scope of the present invention. The operation of the motor 14 is regulated by a conventional switch 20 mounted on a bracket 22 secured thereto and actuated by a switch rod 24 seated in a socket 26 in the upper end of a float rod 28. The float rod 28 in the present pump is tubular, and is supported and reciprocably guided in holes '30 in upper and lower brackets 32 and 34, of similar construction. Each bracket consists of a horizontal arm 36 bent as at 38 into a vertical portion 40 and continuing in an annular portion 42. The latter encircles the supporting tube 12 and terminates in an extension 44 (Figure 4), the extension 44 and the vertical portion 40 being bored to receive a clamping bolt 46.

Slidably mounted upon the float rod 28 is the tubular central support 48 of a hollow air-tight float 50. Also mounted on the float rod 28 above and below the float 50 are adjustable stops 52 and 54 of similar construction. Each stop is in the form of a roughly V-shaped spring member with upper and lower arms 56 and 58 which are loosely bored as at 60 and 62 respectively to freely slide along the float rod 28 when the arms 56 and 58 are pressed together, as by the fingers. When thearms 56 and 58 are released, however, the edges of the holes 60 and 62 tightly engage the float rod 28 and clamp themselves in a fixed position thereon.

The upper end of the supporting tube 12 is seated in a socket 64 in the extension 66 of the motor casing 68. The motor shaft 70 is drivingly secured to the pump impeller drive shaft 72 by a tubular coupling 74 and clamping screws 76. The drive shaft 72 is of tubular construction, containing a central bore or passageway 78 and, immediately above the pump 16, is provided with liquid outlet ports 80. Near the same location, the supporting tube 12 is provided with liquid ports 82 in its side walls (Figures 1 and 4).

Mounted on the lower portion of the drive shaft 72 and secured thereto as at 84 (Figure 1) is a sleeve or bushing 86 which rotatably engages a pump impeller bearing 88 of elastic deformable material, such as natural or synthetic rubber or a mixture thereof. The pump impeller bearing 88 has a bearing core 90 in the center thereof (Figure 3), with vertical grooves 92 spaced at intervals circumferentially thereof for facilitating the flow of water into the bearing bore 90. The pump impeller bearing 88 is of material which is naturally lubricated by water and requires no oil or other artificial lubricant as is ordinarily required for the metallic or sintered powdered metal impeller bearings used in prior sump pumps. The outer surface 94 of the pump impeller bearing 88 is bonded or otherwise firmly secured to the inner surface 96 of the supporting tube 12 to fix the bearing 88 in position at the lower end of the supporting tube 12.

The lower end of the supporting tube 12 is externally threaded as' at 98 (Figurel) and threaded into a correspondingly threaded bore 100 which is preceded by a smooth pilot bore 102, both located in the tubular central extension 104 of the upper half 106 of the pump casing, generally designated 108. By this construction, the outer surface 110 of the supporting tube 12 engages the pilot bore 102, thereby lining up the threaded portions 98 and 100 with one another, as well as locating thesethreaded portions. Moreover, the same construction locates the threaded portions 98 and 100 at a considerable depth below the upper end 112 of the casing extension 104, so that the shearing strain between the pump casing 108 and the tubular support 12 is exerted against a strong solid portion of the latter instead of against the weakened threaded portion 98 as in ordinary constructions.

The upper half 106 of the casing 108 is provided with a hollow cylindrical portion 114 (Figure 1) which extends outwardly from the central extension 104 to a peripheral flange 116, and contains-a cylindrical impeller chamber 118 surrounded by a volute or peripheral flow passageway 120 contained partly within a raised peripheral casing portion 122 of approximately spiral form (Figure 2), increasing in width gradually from one end 124 to the opposite end 126, where it is provided with an upwardly-inclined hollow boss 128 which is internally threaded as at 130 to receive the correspondingly-threaded portion 132 of a pipe coupling: 134, the upper end of which is threaded as at 136to receive the-correspondingly threaded lower end 138 of a vertical outlet or discharge pipe 140. The discharge pipe 140 serves as a standpipe in a manner described in connection with the operation, and extends upwardly out of the sump to a connection with the sewer or othersuitable place of disposal.

The upper half 106 of the casing 108 at its lower side is open, and closing this opening is a stamped closure plate or disc 142 forming the lower half of the casing 108 and having a downwardly-turned edgeflange or skirt 144 likewise having downwardly-extending feet 146 adapted to rest upon the bottom Bof the sump S. The flange 116 and the closure plate 142 are bored with aligned holes and the flange holes 148 are threaded'to receive bolts or screws 150 by which the upper and lower casing ha1ves106 and 42 are secured to one another. The lower casing half 142 is provided with an upturned 2inirjnediately above the skirt 144 to providean annular .lodgment groove 154 for the lower edge of the screen 18. Immediately above the feet 146, the upturned rim 152 isprovided with flattened spots 156 resulting from the formation of the feet 146. Also formed in the lower casing, half 142' or closure plate is an elongated radial trough or depression 158 forming a channel 160 for liquid to flow from the hollow boss 128 to the center of the tubular drive shaft 72, which is open at its lower ejrid jto communicate with the channel 160 (Figure 1).

The casing "extension 104 is provided with a plurality of upwardly=inclined liquid intake or inlet holes or ports 162, four being shown (Figures 1 and 2), these being directed approximately perpendicularly, to the perforated wall portion 164 of the screen19 so. as to provide, in eflectjflushing nozzles for the perforations 166 upon reverse flow of liquid by gravity from the outlet pipe 140, as explained in connection with the operation, for cleaning the screen 18. The latter is of bowl-shaped or dished configuration having its perforated side wall 164 inclined upwardly in an approximately conical formation, and its upper wall 168 approximately flat and centrally bored as at 170 for the passage of the tubular support 12. The lower edge of the screen 18, as previously stated, is held in the groove 154 in the upper surface of the lower casing half 142 adjacent the upstruck rim 152. The screen 18 is held in position by the lower arm 34 which supports the float rod 28 (Figure 1). The upper casing half 106 adjacent the holes 162 is provided with radial webs 172 of approximately triangular form leading from the central extension 104 to the raised spiral portion 122 for strengthening purposes.

The cylindrical impeller chamber 118 contains a pump impeller, generally designated 174, having a hub 176 from which spiral vanes or blades 178 radiate outwardly (Figures 1 and 2). The blades 178 are connected to the hub 176 by radial sectors or webs 180 of approximately triangular or half-crescent shape. The hub 176 is bored and threaded as at 182 to receive the correspondingly threaded lower end 184 of the tubular drive shaft 72, to which it is thereby attached immediately below the sleeve or bushing 86.

In the operation of the invention, let it be assumed that the parts have been assembled in the manner shown in Figure l, with the supporting tube 12 inserted in .the pilot bore 102 and having its threaded portion 98 threaded into the correspondingly threaded bore 100 of the casing extension 104 immediately below the pilot bore 102. This construction enables an unskilled workman to assemble these parts without damaging the threads by misalignment. The float 50 is adjusted to its proper position on the float rod 28 by means of the spring clips or stops 52 and 54, so as to determine the range of water levels to which the switch and consequently the motor 14 will operate the pump 18 to pump out the water from the sump S. When the water level rises to the point where the float 50 engages the upper stop 52, it pushes upward the latter and the float rod 28, together with the switch plunger 24, operating the switch 20 and energizing the motor 14.

The consequent rotation of the motor shaft 70 and tubular drive shaft 72 causes rotation of the pump impeller 174 in the impeller chamber 118, thereby sucking water through the perforations 166 in the screen 18 and the intake ports 162 through the annular chamber 186 in the casing extension 104 and into the impeller chamber 118, whence it is expelled through the volute 120 and hollow boss 128 through the coupling 134 into the dis charge or outlet pipe 140 and thence to the point of disposal. The pump operates until the water level falls to the point where the float 50 engages the lower stop 54, pushing the float rod 28 downward and with it the switch plunger 24, opening the switch 20 and deenergizing the motor 14. p

In the meantime, water flows freely through the ports 82 in j'tubular support 12 ii1to the llatterabove the pump rotor-bearing SSandI th encejthrough the axial grooves 92 thereof into the bearing bore 90, lubricating the bearing 88 in its. engagement with the rotating sleeve 86 attached to the driveshaft 72. If, for any reason, the pump should remain runningafter it has pumped the liquid down to"'th'erequired minimum level, water will still flow back through the' bore 78"in"the drive shaft 72 and outwardthroughthe ports tog lub ricate the bearing 88-and prevent it from burning out, M

When thepump ceases operation in te normal manner,,the water which has been forced upwardjnto the outlet pipe and remaining therein now descends by gravity into the impeller chamber 1 18 and thence gushes outward and;upward through theports 162 and perforations 166 in the screen 18, washingotfi foreign matter which rnay have temporarily clogged these perforations. From time to time, the operator or owner by means of a flashlight, can look down into the sump and examine the perforated wall 164 of the screen 18 which is easily visible because ofits upwardly-inclined configuration. If he finds by his inspection that the screen requires cleaning, he can quickly and easily do so by means of a broom, long-handled brush or mop lowered into the sump and moved to and fro over the screen 18. The bearing 88, being above the suction ports 162 of the pump 16, is free from grit or dirt which would otherwise be forced into the hearing if, as in certain prior sump pumps, it were located on the discharge or pressure side of the pump.

What -I claim is:

1. A sump pump comprising an elongated upstanding motor supporting tube having an upper end portion adaptedto receive and support an operating motor, a pump casing structure mounted on the lower end portion .of said supporting tube and having a pump impeller cavity therein, said casing structure having an inlet port and an outlet port communicating with said cavity, said supporting tube having a hollow bearing supporting portion within the lower end portion thereof disposed centrally of said cavity, a shaft sleeve bearing of waterlubricated material secured in said bearing supporting portion .and having its lower end communicating with said cavity, a hollow pump impeller drive shaft journaled in said bearing and adapted to be operatively connected at its upper end to the motor, and a radial-discharge pump impeller rotatably mounted in said cavity and drivingly connected to said hollow shaft, said supporting tube near the upper end of said bearing having a lubricating port extending therethrough from the exterior thereof and communicating with the upper end of said bearing, said hollow shaft having a lubricating water passageway extending therethrough from said cavity to said bearing, said shaft having an outlet from said passageway communicating with said bearing.

2. A sump pump comprising an elongated upstanding motor supporting tube having an upper end portion adapted to receive and support an operating motor, a pump casing structure mounted on the lower end portion of said supporting tube and having a pump impeller cavity therein, said casing structure having an inlet port and an outlet port communicating with said cavity, said supporting tube having a hollow bearing supporting portion within the lower end portion thereof disposed centrally of said cavity, a shaft sleeve bearing of waterlubricated material secured in said bearing supporting portion and having its lower end communicating with said cavity, a hollow pump impeller drive shaft journaled in said bearing and adapted to be operatively connected at its upper end to the motor, and a radial-discharge pump impeller rotatably mounted in said cavity and drivingly connected to said hollow shaft, said supporting tube near the upper end of said bearing having a lubricating port extending therethrough from the exterior thereof and communicating with the upper end of said bearing, said hollow shaft having a lubricating water passageway 7 sxtending therethrough from said cavity to said bearing, said shaft haying an Outletfrom Said passageway communicating with s'aidlbziriil g, and said casing structure having a Water chrinl'xj'tjendihg from said outlet to said hqlldw shaft passageway: beneath said impeller.

rReferel ages cited the 1116 of this patent ,UNIT ED STATES PATENTS 870,310 ODonnell Nov. 5, 1907 1,273,913 Ostenberg' 1---; July 30, 1918 1,488,237 Durd'in' Mar. 25, 1924 1,500,607 Conant July 8, 1924 1,695,846- Harding Dec. 18, 1928 1,705,263 Mc'llvaine Mar. 12, 1929 1,758,391

Dil nham May 13, 1930 Yoder Oct. 18, 1932 Maclachlan July 25, 1933 Morgan NOV. 2-7 1934 Lappert Nov, 14,1944 Ingersoll Apr. 30, 1946 Bowman Mar; 7, 1950 Pollak 061. 10, 1950 Brady Feb. 20, 1951 Berry Mar. 20, 1951 Topanelian Nov. 20, 1951 Calling Feb. 21, 1956 Lung Oct. 16, 1956 FOREIGN PATENTS 1 Australia -2. Apr. 23, 1945 Great Britain Apr.'4, 1951 France Aug. 26, 1946

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