US2732804A - Automatic pressure liquid supply system - Google Patents

Description

Jan. 31, 1956 SADLER ET AL 2,732,804

AUTOMATIC PRESSURE LIQUID SUPPLY SYSTEM Filed April 24, 1950 2 SheetsSheet l 455/ dzwr/za 1/ WW Jan. 31, 1956 I ADL R ET AL 2,732,804

AUTOMATIC PRESSURE LIQUID SUPPLY SYSTEM Filed April 24, 1950 2 Sheets-Sheet 2 ir/zedi Z 6001 fly z%6/7242292/2@/ WWW United States Patent 'fi AUT OF/IATIC PRESSURE LIQUID SUPPLY SYSTEM Harry} I. Sadler and Ernest ook; Minneapolis Miriam,-

assignors 'to-Hypro Erigineering C03 Minneap'olis,

Minn.,- a corporation of Minnesota Application April 24; 1950;Se'rialNi). 157,788

3 Claims-4J6]? 103 -25) Generally stated, our present inventionrelates to improvements in automatic water pressure supply systems ofthe kind commonly employed, particularly' in rural areas, to supply running water under pressure from wells.

start the pump motor when the pressure at the outlet side of the systemtand said chamber drops below a predetermined minimum pressure and to stop-the motor when the pressure in the outlet side of thesystem and said chamber rises above a predetermined maximum pressure.-

One important phase of the invention relates to sys' tems-of the kind described Whereinthepump, pump motor, and the tank forming the pressure chamber, are

constructed and assembled toprovidea self-contained complete pumping unit, which unit may also involve the automatic pressure actuated control-for the pump motor With respect to this phase of the invention, an important objective is the provision of a low-cost, simplified and exceptionally compact, neatvand attractive. unit of the class described. Toachieve this objective, we provide a common mounting base for the pump motor andother parts, which mounting base is integrally formed to pro? vide a chamber-defining tank .portion andwmountingtsura faces for the motor and pump. Inviour improvedcon-f struction, themotor mounting surfaceis horizontally offset fromuthechamber-defining tank portion of the,

base, and the pump mounting surface-is located on top of-thevchamber-defining tank-portion of the'baseand is sufliciently above the planeof the motor mounting surface to compensate-for the relatively-great,difference in physical dimensions between .thelpunipu and .motor; it

beingunderstood thattin units. of the. kind, under consid-.

oration, the pumps .which are usually? ofthe wrotary variety are of relatively smallidiameter orradius as compared to then-rotors;

Another phase ofthe instant invention has.as an impontant' objective.theflprovisiomainra systernof thekinddescribed; means .for automatically preventing undesir ablyrapid-recycling of.the-pump and motor under conditions of prolonged but highly restricted flow when the capacity of the pump greatly exceeds the rate of discharge.

The above and highly important fobje'ctstand advantages: :of the invention will be madeyapparent from-the followingspeciiication, claims and appended drawings In the accompanying drawings, like characters indicate like parts throughout the several. .viewso 2,732,804 Patented Jan. 31, 1956 Referring to the drawings Fig.21 is a view inside elevation of acornpletepumpw ing unit of the invention; some parts broken away= andsomeparts shown in section? I p Fig. 2 is a plan view of the pumping unit of Fig. l with some parts broken away-and some parts sectioned;

Fig. 3 is an enlargedf-ragmentary-sectional View taken on the.line 33 of Fig. 2, with someparts brokenaway;v

Fig. 4 is an enlarged fragmentary sectional view taken approximately on the line 44 of Fig.2, with-some -parts=- broken away; I

Fig. 5 is a fragmentary bottomplan view taken on the linei 5.5 of Fig, 4; and p Fig. 6 is a view largely in schematic- -diagramand illustrating the hook-up of certain of the component elements or devices of the system;

The commercial embodiment of the invention- -illus-' trated-in the drawings. comprises a conventional electric motor M, a positive displacement-type rotary pump P and acommon mounting base 1 for the pumpand motor. This common mounting base 1 is preferably a cast structure integrally formed toprovide a superstructure supporting top wall 2 and a depending and preferably endless marginal flangeorwall 3. This base 1 iselongated andone end portion of the superstructure supporting top: wall 2 is relatively thin and solid and has a flat motormounting surface 4 substantially inthehorizontal plane of the top of the marginal flangetor wall 3. a The other end-portion of this superstructure supporting -top wall T2 1' of the main base 1 is hollow and is bulged both above and below theplane of the top of the skirt-likemarginal' flange or wall3 to provide a sealed chamber 5 and a flat pumptmounting surface 6 that is materially above the. plane of the motor mounting surface 4. The -motorM is providedwith its own mounting base 7, when is seated on the flat motor mounting surface 4 andis bolted in placeat 8.. The pump P is provided with its' individual mounting base which is seated on the fla ttv pump 1 mounting surface 6 and is securelyheld in placeby'bolts or the like 10.

The pump shaft 11 is directly connected tothc' motor i shaft 12by a conventional coupling 13,. the shafts l-l 'and 12 being in coaxial alignment, Byrefe'r'enc'e particularly tovFig. 1, it will be seen tha't the overallCradius' .of the. motor M as measured throughlitsmountingbase is very much greater than the overalllradius ofi=the pump ,P as measured through its mounting base, randthat thediffer-v I ence in elevation between" the pump mounting surface 6 and the motor -mounting surface; 4 resulting'from ,the'" upward bulging. of the top wall-2 to provide the-pressure chainber- 5 is substantially equal to 'theldifie'r ence in the,. said-"overallradial measurements of the pumpand motor; and thereby automatically brings about horizontal, axial alignment between the shafts 11 and12 of the-pump and. 17 motor respectivelyj V The inlet coupling sleeve of.=thi pump P is indiciited by Hand is adapted to be connected to a well'dr other suitable source of water-by a pipe lineor conduit "sec.- tion 151 The dischargehor outlet couplingof the pump I P is indicated by le-Yan'd is adapted to'be coupled to 'a suitable remote discharge valve lortvfauceg'fnot' shown, through, the medium of a conduit or pipe linesection- 171"" The outlet side of the pump? is connected toithelower f portion of the-fluid pressure chamber- 5 through, the; coupling sleeve .l6i and 5 depending conduit section-1 81" Pressure within 'thchainbei' 5 is visuallyfindicated'byf'a 3 conventional pressure gage 19.

As, in" other systems bf "thefs'amei genefal cla'ssfth 5? pump motor M i's automaticallyeontrollnpy apressure responsive control switch mechanism having a pressureresponsive element exposed to pressure in the chamber or equivalent. For the purpose of the present invention, any one of several commercially-available pressureresponsive controls may be employed. Such a conventional pressure-responsive control may be assumed to be contained within a control housing Zil of the drawings and comprises a pressure-responsive actuating element, which may be in the nature of a bellows 21 (see Fig. 6). This pressure-responsive element or bellows 21 is exposed to internal pressure of the chamber 5 through the medium of a standpipe 22, which serves as a mounting medium for the pressureresponsive motor control switch mechanism contained Within the housing 20. The control switch mechanism within housing 20 may be assumed to be of the double pole variety and to be interposed in both of the powersupply circuit leads 23 and 24 of the motor M (see Fig. 6). It will be understood that pressure-responsive control switch mechanisms of the kind contained within housing 20 will automatically complete the motor circuit and start the motor M when the pressure in the chamber 5 drops below a predetermined minimum pressure and automatically closes the motor circuit and starts the motor M when the pressure Within chamber 5 rises above a predetermined maximum pressure. It will further be understood that in systems of the kind described, a considerable head of air is maintained within the fluid pressure chamber 5 for the reason that air is compressible and provides a cushion, which effectively reduces the speed at which the pressure changes take place in 'the system.

When, as in accordance with the presently-described system, a positive displacement type of pump is employed, as distinguished, for example, from the centrifugal impeller type, considerable trouble or annoyance has heretofore been encountered with unduly rapid and undesirable recycling of the pump and motor, particularly under conditions when the capacity of the pump, by virtue of great restriction of the outlet thereof greatly exceeded the rate of discharge; this undesirable condition resulting in a very rapid building up of pressure within the control chamber 5 from the motor starting minimum pressure to the motor stopping maximum pressure, even when a relatively large air space was present in the chamber 5 or its equivalent, and a relatively wide tolerance was provided between motor stopping and motor starting pressures.

In accordance with the present invention, the last above noted objection to prior art systems of the class under consideration is obviated by the simple expedient of providing a check valve controlled by-pass conduit or passage 25 between the inlet and outlet sides of the pump P (see particularly Fig. 2). This passage 25 is formed to provide an annular valve seat 26, the orifice through which is controlled by a normally-closed check valve 27, which is pressure-opened and is yieldingly biased toward its closed position against the seat 26 by a compression spring or the like 28. The valve 27 is formed on the end of a valve stem 29 extending through the spring 28 and slidably mounted in a threaded plug 30, which serves also as a base of reaction for the valveclosing spring 28. The valve 27 is, of course, fully closed when the pump is inoperative and remains closed under conditions of relatively unrestricted discharge from the outlet side of the pump when the pressure in the chamber 5 is essentially very low. However, during periods of pump operation when the flow through the system is retarded, by a relatively high restriction in the outlet side of the system, to the point where the capacity of the pump materially exceeds the rate of discharge, the pressure in the outlet side of the pump will rapidly build up sufiiciently to open the valve 27. Of course, the extent to which the valve 27 opens will depend upon the degree of pressure at the outlet side 'switchof the pump and the adjustment of the valve biasing spring 28 through the medium of threaded plug 30. When the valve 27 is open, fluid will by-pass through passage 25 from the outlet to the inlet side of the pump and thereby greatly reduce the rate at which pressure is built up in the chamber 5 to the motor cut-off pressure of control 20, thereby greatly reducing the frequency of recycling of the system under the conditions mentioned. However, another important advantage of the valve-controlled by-pass 25 is the elimination of motor overload or stailing. It will, of course, be further appreciated that the pressure at which the valve 27 opens may be adjustably varied by varying the pressure exerted on the valve by spring 28 through the medium of the knurled head-equipped screw-threaded plug 30.

The above and other important objects and advantages of the invention will be made apparent from the following claims and appended drawings.

What We claim is:

1. In a self contained complete liquid supply unit, an elongated mounting base comprising a top wall and a relatively shallow flange integral with and depending from the perimeter thereof, said top wall having a relatively fiat motor mounting surface adjacent one end thereof and in the plane of the top of said'fiange, said top wall adjacent the opposite end thereof including opposed Wall portions arched upwardly and downwardly from said plane and providing a pressure chamber, the lower arched wall portion being disposed within the vertical range of said flange and the upper arched wall portion being provided with a fiat pump mounting surface parallel with and materially above said motor mounting surface, a pressure pump having input and output sides mounted on said last mounting surface with its axis parallel to said plane, a motor of substantially greater vertical dimensions than said pump mounted on said first mounting surface with its axis horizontally aligned with the axis of said pump, a drive shaft operatively connecting said motor and said pump, and a liquid conduit connecting the output side of said pump to the interior of said pressure chamber.

2. In a system of the type defined in claim 1, in which a liquid supply is connected to the input side of the pump, a by-pass connecting the input and output sides of said pump, a motor control means also mounted on said last mentioned surface and being in communication with the interior of said pressure chamber, a variably adjustable pressure responsive valve means in said by-pass preventing rapid build up of pressure therein and in said pressure chamber and thereby reducing the speed of motor cut-off by said motor control means under restricted flow from the output side of said pump.

3. An automatic pressure liquid supply system including a mounting base, a pressure chamber in said base, a pressure pump having inlet and outlet sides supported on said base, a motor supported on said base in driving connection with said pump, a conduit connection between said chamber and the outlet side of the pump, pressure responsive motor control means in communication with said pressure chamber, a bypass in said pump intermediate the inlet and outlet sides thereof, a variably adjustable pressure responsive valve means in said bypass, said valve means being responsive to pressure in said outlet side of the pump preventing rapid build up of pressure therein and in said pressure chamber reducing the speed of motor cut-ofi by said motor control means under restricted flow from the output side of the pump.

References Cited in the file of this patent UNITED STATES PATENTS (Other references on following page) Hagenbucher Aug. 1, 1916 Weatherhead et a1. Oct. 17, 1916 Anderson Feb. 13, 1923 Jennings Feb. 27, 1923 Gardner Mar. 27, 1923 Lawhead Aug. 5, 1924 Buvinger June 9, 1925 Buvinger et a1. June 7, 1927

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