US2029765A - Pumping apparatus - Google Patents

Description

A. c'. DURDIN, JR

PUMPING` APPARATUS Filed April 7, 1934 3 Sheets-Sheet 1 cf/uguf uhs C. Bard/n, Jr.

JATTORNEY.

` Feb'. 4, 1936.

i Feb. 4, 1936. l A. c. DURDIN, JR l 2,029,765`

f PUMPING APPARATUS Filed April 7,5 1934 3 Sheets-Sheet 2 INVENTOR.

l gy/M ATTORNEY.

Patented Feb. 4, 1936 C Q UNITED STATES PATENT .o1-FICE v PUMPING APPARATUS Augustus C. Durdin, Jr., Chicago, lll., asslgnor to Chicago Pump Company, Chicago, lll., a corporation of Illinois Application April '1, 1934, serial No. '119,463

' 5 claims. (ci. 10a-11) This invention relates td pumping apparatus, It further consists in control means employing and more particularly to means for automatically pressure to vary the size of the discharge outlet regulating the capacity of one or more pumps, of the pump, and responsive to fluctuations in the without varying the speed thereof, whereby the inilowof the liquid.

5 pump or pumps operate lto pump liquid from a It further consists in control means for regubasin or other reservoir at approximately the lating the output of both pumps of a duplex same rate of pumpage as the inflow of the liquid equipment, in such manner that the capacity of thereto. each pumpv is increased from a minimum to a In many situations, as for example in sewage maximum, whereby the pumpage will conform treatment plants, the desideratum is to deliver approximately-to an increase of iniiow from a 10 the sewage to the treatment plant at approximinimum to a maximum. f mately the same rate of o'w as the inflow of the It further consists in the provision o f means sewage, and attempts have been made to accomfor alternating the operating of the pumps of a plish this result by varying the speed of the pumps duplex pumping .equipment and simultaneously to correspond with the flow of the sewage, but therewith transferring the capacity control so as 15 it has been found that this method is not ecoto operate first in connection with the leading nomical, the control apparatus is very costly and pump. is prohibitive except when used in very large It further consists in the several novelI features plants. of construction, arrangement and combination of One of th objects of this invention is to proparts hereinafter fully set forth and claimed. 20 vide automatic control means for pumping appa- The invention 'is clearly illustrated in the ratus, which is simple, practical and economical drawings accompanying this., specification, in in operation. which:

Another object ,is to provide automatic control Fig. 1 is a view, partly in side elevation and means for pumping apparatus, responsive to theV partly in vertical section of ypumping apparatus 25 inflow of liquid, for regulating the capacity of a embodying a simple form of the present invenpump or a plurality of pumps, without varying tion in connection with a duplex 'pumping equipthe speed thereof, 'whereby the pumpage shall I ment; approximately equal the inflow of the liquid. Fig. 2 is a View thereof, partly in plan and yAnother object is to provide automatic control partly in horizontal section, with a oor partly 30 means for regulating the capacity of the pump, broken away to show parts located therebelow; by controlling the sizeof the discharge outlet of Fig. 3 is a plan, partly broken out, of the' ow the pump, whereby the pumpage approximately regulator of the capacity controlling means for equals the inflow. the pumps;

Another object is to provide a duplex pumping Fig. 4 is a diagrammatic view illustrating one 35 equipment with automatic control means whereby form of electrical control for the pump motors, the rate of discharge is varied from a minimum and a transfer valve used in the capacity regulatto a maximum flow, proportionate to the rate of ing control, and

- inflow, and wherein the capacity of each pump, Fig. 5 is a perspective view of one form of alterin succession, is gradually increased from a mini` nator used in the apparatus. 40

mum to a maximum. In the accompanying drawings, the invention Another object is to provide a duplex pumping has been illustrated as applied to a sewage treatequipment. having a variable capacity, with automent plant, although it is to be understood that matic'means for alternating the operation of the its use is not limited thereto as it may be aptwo pumps of the equipmen. plied in any situation where the desideratumis 45 Another object is to provide pressureactuated to pump liquid approximately at thesame rate. means for'varying the capacity of a pump, reof pumpage as the inflow tot the pumping apsponsive to fluctuations-in the 'inflow of the liqparatus. uid, In the drawings, the reference character Il) des- With these and/ other objects and advantages ignates the terminus 4of a' tnmk sewer, usually 50 in view, this invention consists-in pumping appalocated several feet underground, and 28 desigratus having control means, responsive to fluc` l nates a conduit, located at some considerable distuations in the inowtof liquid, for regulating the tance above the sewer terminus, through which capacity of a pump so as to conform to the rate the sewage is conveyed to a sewage treatment of inflow, without varying the speed of the pump. plantV or to some other place'for disposal. The 55 4pumping apparatus is housed in a structure II desirably composed of masonry, concrete or the like and having a pump pit I5 for .the pumping apparatus and a motor room thereabove for the motors and other equipment. The motor room is usually roofed over and its floor I2 covers the pit and contains an opening for access to the pit, the opening being ordinarily closed by a trap door I6.

The invention is illustrated in connection with a'duplex pumping equipment, and the two pumps I1 thereof are mounted on the floor l5a of the pit, and connected to two electric motors 3l, 3I by shafts 29 and couplings 30. The pumps shown are of the centrifugal type and their suction inlets I8 communicate with the inlet conduit or sewer terminus I0, througha basin or other reservoir here shown in the form of a well I4 built into the structure II, and separated from the pit by the wall I 3. The sewer terminus I 0 discharges into the basin, usually through a screen, and the inflow to said basin fluctuates considerably in any given station. The capacity and number of pumps required is determined by the approximate minimum and4 maximum iniiow intended to be handled.

The discharge side of each pump is connected to a riser 21, which leads to the discharge condu- 28. Desirably a shut-off valve I9 is interposed between each pump and its suction inlet I8 and a shut-01T valve 24 is interposed between the pump and riser 21 whereby the pumps and associated connections may be cut out of service for the purpose of repairs or for any other purpose. 'I'he shut-off valves I9, 24 may be operated from the motor room by extension rods 2U, 25 that extend up through the oor I2 and have handwheels 2l, 26 on their upper ends. A check valve 22 is employed on the discharge side of each pump to prevent return flow through the pump.

Associated with ach pump, tion side or its discharge side,

either on its sucand formed as a I part of.the pump or separate therefrom, is a sure used to extend the diaphragm capacity regulating device 23 here shown as interposed in the connections between the dis# charge side of the pump andthevriser 21. The capacity regulator is shown in the form of an elbow having an opening in one side (see Fig. 3) over which is a flexible diaphragm 40, held in place by a cover 39 bolted to the elbow around said opening. The diaphragm and cover provide a pressure chamber 40a into which aiiuid under pressure is admitted to extend the diaphragm more or 1essto thereby vary the cross sectional area of the passage through the elbow,-

and as a'result vary the rate of flow of liquid discharged bythe pum and as a consequence varying the capacity of the pump. It will be observed that when the diaphragm is fully extended, it closes or substantially closes the passage through the elbow, and that the size of said passage may be increased to its full capacity by vpermitting the diaphragm to collapse.

Compressed air or other uid under pressure is used to extend the diaphragm, and in the form of the invention illustrated, a supply pipe line 43, 4I, having a fitting 42 therein, containing a restricted orifice, conveys the iluid under pressure to the pressure chamber 40a. The pressomewhat in excess of the pressure set up by the pump.

In order to regulate the rate of discharge from a. pump to conform to the rate of inflow to the as comprising waste valves other motor. The iioats 33, 33al should` be' basin I4, control means are provided for regulating the pressure in the pressure chamber 40a, whereby to regulate the size of the opening through the capacity regulator so as to permit a rate of flow therethrough approximately the same as the rate of iniiow to the basin, up to a maximum amount, namely the full capacity of the pump. The control means is here shown 48, 48a, one for the capacity regulator of each pump, these valves being in the form of float valves located in the basin I4 and each connected to its associated capacity regulator by separate pipe lines 41, 44 and 41a, 44a. The float valves 48, 48a are provided with floats 59, 50a i9a and arranged to be lifted to open the passage through the float valves as the liquid rises in the basin. It will be observed that as either float rises, due to the rise of the level in the basin, its associated float valve gradually opens n the discharge orifice therein, thereby permitting the fluid under pressure to escape from the associated pressure chamber 40a and consequently the diaphragm is collapsed more or less depending upon the leakage through When the iioat is lowered to its extreme low position, the iloat valve closes and the pressure chamber thereupon receives the full amount of pressure and consequently the passage through the capacity regulator is closed or substantially closed, and when the float is raised to its extreme upper limit, the leakage through the oat valve is suflicient to the diaphragm under the pressure set up by the pump, consequently the latter operates at its full capacity.

In a duplex pumping equipment float switches are usually employed for starting and stopping .the pump motors and two switches 35, 35e are shown for that purpose. The float 33 of the switch 35 is set ata lower elevation than the lloat 33a of the switch 35a, whereby the switch 35 will close when the liquid in the basin reaches a predetermined level and thereby start one of the pump motors, the other one remaining idle unless the inflow exceeds the capacity of the running pump, in which case if the liquid rises sufficiently it will raise the float 33a and close the switch 35a to their switches'by iioat rods casings 32.

In order that the capacity of each pump may gradually increase so that the pumpage may cor- 34 contained in respond to the rate of inflow to the basin, the

float valve 48EL is set at a higher elevation in the basin than the float valve 48. As a result, when the inflow increases to the maximum, the capacity of the pump which is started rst, is gradually increased to its maximum, the second pump is then cut in, at `rst operating at its minimum capacity, and then gradually increasing until it runs at full capacity. I

It will be seen therefore that the rst pump to start operates at its full .capacity before the second one is cut in, and that the first pump continues to run at its full capacity when the second pump is cut in, until the liquid has been pumped out of the basin down to a second pump has stopped, and then the capacity of the active pump is decreased of inflow decreases.

In order to distribute the wear on the two pumps and their motors, an alternator 5I (see Fig. 5) may be provided for transferring the only as the rate the float Valve.

thereby starting the.

are connected permit the complete collapse of to main line L and from main line L3 through circuit, controlled by the pilot switch 35, from one motor to the other. The alternator may be arranged to be actuated by time controlledmechanism so that one pump will operate first, for a predetermined length ofl time and then the other pump will operate for the same length of time. Mechanism for operating the two pumps during certain predetermined intervals of time is clearly No. 1,780,380 issued to me November 4, 1930.

The alternator shown in .the accompanying drawings is chosen for the purpose of illustration only and operates to transfer the circuit, controlled by the pilot switch 35, from one motor to the other so that the motors will be started alternately at the commencement of successive Dumping operations.

The alternator shown is provided with twolsets of movable, spring actuated contactors 52, 53, and 528, 53B, of which the contactors 52, 52

will close circuits during one cycle, and then the contactors 53, 53a will close circuits during the second cycle and so on. Stationary contactors 52X, 53x and 522, 53z co-operate with the movable .contactors to close the circuits therethrough. A shaft 60, journaled in brackets on the panel 5|EL of the alternator, has toothed or notched wheels the starters.

andthe solenoids 55, 558L `45 hereafter referred to.

6|, thereon that act ,on the movable contactors to swing them back from the stationary contactors, when the teeth -or high partsy of the wheels engage them.l The spaces between the teeth or high parts of the wheels permit the mov- `able contactors to swing into contact with the stationary contactors. Conveniently all of the contactors are mounted on the panel 5|.

Actuatingmechanism comprising holding coils 54, 54a, mounted on the panel, an armature 62, a pawl 53 connected thereto and a ratchet wheel 64 fast on the shaft 50, is provided for intermittently rotatingthe shaft 60, to thereby reverse the position of the movable contactors at the Vconclusion of. each cycle of operation of the A holding coil 54 or 54a isenergized at the commencement of a cycle of operation and the armature is attracted, thereby setting the pawl in position to engage the ratchet Iwheel,

`and when the holding coil is def-energized the armature is swung back by a spring 64 thereby engaging the pawl with the ratchet partially rotating it so as to bring the notches of each toothed wheel into the position formerly occupied by the high places or teeth, thereby reversing the positions formerly occupied by the1 movable contactors and transposing the circuits. The holding coil 54 or 541iI holds the actuating "mechanism in a set position as long as either of 35a is in closed position,A

theiloat switches 35 or but as soon as the. float switches 35 or 358L a'ie opened, either or both of theholding coils are de-energized and the actuating mechanism for the alternator transfers the relationship of the contactors 52, 53 and 52%,.531.' Lines lead from" the float switches 35, 35a to the alternator as shown in Fig. 4, and from the alternator, lines 'lead to the starters 31; 31a. Motor safety "switches 36, 36a are ordinarily placed in the main line to In Fig. 5 are shown binding posts from which lines lead to the contactors and holding coils, and from which the lines lead to the pilot switches, the holding coils of the starters The starting circuitfor motor 3| from pilot switch 35,

maybe traced through line a, contactors 52, 52x, line b, holding coil of starter 31,

shown and described in Letters Patent through line 1i.

wheel andthat operate the valvev regulator of line c, back switch 3 5a may be ltraced through line k, contac tors`52a, 52, line g, to holding coil of starter 31 and to main line L, and from main line L3 through line l, to pilot switch 35. The circuits through the holding coil 54El and solenoid 55a can be traced from the line g, line i, through holding coil 54a, line 7' to main line L and through line i to solenoid 55a, and line 7 back to main line L. line L3 through line l, to pilot switch-35B.

When the contactors are in reverse position, the starting circuit' for vthe motor 3| from pilot switch 35 may be traced through line f, contactors 53a, 53z (when closed)` line g, holding coil of starter 31"L to main line L: From main line L3 In case pilot. switch 35 is closed thecircuit for the starter of motor 3| may be traced from pilot switch 35, through line m, con- actors 53, 53, line b, to holding coil of starter V31 and to main line L. From main line I through lines l, and u to pilot switch 35B. Holding coil 54 and solenoid 55 are also energized without affecting any of the other mechanism.

When the capacity control mechanism, is used :z

with automatic means for alternating the opera.- tion of the motors, it is desirable that the float valve 48 which is set at the lowest elevation, shall From main 54e and solenoid 55B 53z and -line i and back control the capacity regulator of the pump which rst starts to pump when the liquid rises sufllcientlyfto close thepilot switch 35. A duplex three wayvalve 45 in the pipe lines 44, 41 and 44a, v4111, for the two capacity regulators is provided forthis purpose (see Fig. 4). The valve has a cylindrical casing 45 which contains a bore in which is a rocking plug 46 having a stem 56 by which it is rocked. The two pipes 44, 44B' from the capacity regulators, enter the valve casing from one side thereof and the pipes 41, 41=L enter the casing from the other side. The plug 46 contains two ports 4t which in one position of the plug, fform direct connections between the pipes 44, 41 and 44a, 41a, and the plug also coniains ports 4Bb'which in another position of the plug, form connections between the pipes 44, 41e

and 44e, 41. When the plug occupies one of these positions, the passage from the lower most Afloat valve 48 is open through the pipe 41, port 46S, and

pipe 44 ,to the capacity regulator 23 shown at the upper half of Fig. 2, and the passage from the upper float valve is open through pipe 412L port 46n and pipe 44 to the other capacity regulator.

When the plug is shifted to the position shown in upper float valve is open' to the other capacity' 'regulaton Regardless of which pump starts first in any cycle of operationthe lowermost oat valve is always in connection with the capacity the pump which starts first.

The valve 45 is arrangedto operate synchronously with the alternator.

nected'to and operated by two electro-magnetic gli) As shown the plug stem 56 has an arm 56'on its outer end, conthe float switch 35.

pilot switch 35 starts motor 3| a.

devices such as the solenoids 55, 55a, the lines of which lead to the alternator. The windings of the solenoids 55, 55u are connected in parallel with the holding coils 54 and 54a, so that when either float switch causes the holding coil 54 to become energized, the solenoid 55 is also energized, and this rocks the valve stem 56 to set the valve plug in one position, and when the holding coil 54a is energized, the solenoid 55a is also energized and the valve plug is rocked back to its former position.

The operation of the duplex equipment illustrated is substantially as follows:

. Sewage from the trunk sewer I enters the basin I 4 and commences to ll up the storage capacity thereof. As the float 33 of the pilot switch 35 is set at a lower elevation than the other one, the water level soon reaches the place at which the lower fio-at will close the circuit through This will start either motor 3| or 3la depending upon which one is in circuit through the alternator and its attendant starter 31 or 31a. Fluid under pressure enters through the supply pipes 43, 4l and passes through the restricted orices 42 into the pressure chambers 40E of the capacity regulators for the two pumps. As the valve 48a is set higher than the valve 48 the valve 48a remains closed, and the float 50 of the lower valve 48 will be acted upon first by the rising water level. With the valve 48 closed until its float 50 is lifted, the pressure entering the pressure chamber of the active pump causes the diaphragm to be extended to close .or at least greatly restrict the flow through the discharge line and thereby out down the capacity of the pump. As the water level rises, the Iioat 50 is lifted and the valve 48 is partially opened, thereby permitting the escape of some of lthe fluid under pressure, passing through the .restricted orifice 42, and as the uid under pressure escapes in increasing amounts as the valve 48 opens, it permits the diaphragm to retract and open the passage of the discharge line proportionately. When sewage enters the basin in increased quantities, the oat f] rises to open the valve 48 fully, and as this relieves the pressure behind the diaphragm, the latter fully retracts and fully opens the discharge passage pump delivers at its full capacity.

As the flow through the trunk sewer 0 approaches its peak load, sewage enters the basin faster than the active pump can discharge it. Shortly after the float 5i! has fully opened the valve 48, the level of the water reaches the float 5i)a of the higher valve 48a and also reachesthe iioat 33a of the float switch 35a thereby starting the other pump motor. As the water level rises in the basin, the valve 48a is gradually opened and the capacity of the second pump is gradually increased to its maximum, Vwhereby the second pump delivers at its full capacity,'if the level rises sufliciently to fully open the valve 48a.

AAs the peak period passes, the two pumps empty the basin, and when the water level falls to predetermined points, the second pump to start will gradually reduce its capacity until the float switch 35a opens the circuit thereto. Then as the level continues to recede, the pump which started first, gradually reduces its capacity and stops when the water reaches a low level and the eat switch 35 opens the circuit. The alternator then transposes contactcrs 52 52a and 53 53a so that upon the next cycle of operation the With the transfer in the sequence of operation of themotors.

so that the activecapacity regulating tween the capacity the transfer in the sequence of operation by the float valves 48, 48a will be brought about by the duplex three way valve 45.

The levels indicated by the lines A, B, C, D, E and F in Fig. 1 may serve to indicate the sequences in operation under diiferent conditions. With the pumps at rest and sewage owing into the basin during an approach to a maximum inthe water'rises to level C, one pump starts. As the water approaches the level B, this pump delivers at its full capacity. At level E the other pump starts and at level A both pumps operate at full capacity. As the sewage is withdrawn from, the basin, and its level falls to line F the second pump to start cuts out, and

`when level D is reached the rst pump to start cuts out.

A capacity regulator having a flexible diaphragm has a particular advantage in that there is no likelihood for material to collect in the regulator and interfere with its operation. When the passage through the regulator is very restricted, solid mattei' may clog the passage temporarily, but the rise of water in the basin will cause the float valve to open, permitting the diaphragm to collapse, thereby allowing the collected material to pass on, after which the parts function normally again.

While a pressure operated diaphragm device has been shown for regulating the rate of discharge by each pump, equivalent means such as a valve operated by pressure or by other power may be substitutedtherefor. Furthermore, any number of pumps may be used at one station to take care of extreme cases. The several pumps may be caused to operate in sequence upon an abnormal inflow by arranging the float switches and oat valves at different elevations in the basin.

Furthermore various types of alternators may be used, or the alternator may be omitted and ordinary hand switches may be used to change the sequence of operation of the two pumps.

I claim as new and desire to secure by Letters Patent:

1. In duplex pumping apparatus, a pair of sequentially operated pumps, each having fluid pressure operated capacity regulating means, and sequentially operating waste valves for regulating the amount of pressure admitted to said means, pipe connections beregulating means and waste valves, and a valve for connecting the initially operated waste valve with the capacity regulating means of the initially operated pump.

2.1In duplex pumping apparatus, a pair of motor operated constant speed pumps, capacity regulating means associated with each pump, automatic means for causing alternate and sequential operation of the two pumps, separate sequentially operable control means for the capacity regulating means, responsive to fluctuations of a liquidlevel in the pumping system in which the apparatus is `used, and automatic means for connecting the capacity regulating means of the pump which starts rst in a sequence of operation, with the control means which operates first in sequence.

3. In duplex pumping apparatus, a pair of motor operated constant speed pumps, pressure operated capacity regulating means associated with each pump, each having control means responsive to the uctuations of a liquid level/in the pumping system in which the apparatus is used, one control means 'functioning at a higher 4. In pumping apparatus, the combination of va pair of motor operated, constant speed pump units connected to a basin arranged to receive a uctuating source of liquid supply, iioat controlled, minimum to maximum capacity regulating means associated with each pump for varying the capacity thereof to conform to flucl tuations in theyrate of inow to the basin; said floats being located in the basin, and individual float switches for starting and stopping the motors of the pumps, the two floats for one pump unit being set at a higher liquid level than those of the other pump unit, whereby one pump unit starts when the liquid level reaches one level and its capacity is increased from minimum to maximum upon the rise of the liquid level to a higher level and the `other pump starts upon the rise of the liquid level above said higher level and its capacity increases from minimum to maximum upon continued rise of the liquid level `above said higher level.

5. In pumping apparatus, the combination of a pair of-motor operated, constant speed pump units connected to a basin arranged to receive a tluctuating source of liquid supply. uid pressure operated minimum to maximum capacity regulating means associated with each pump for varying the capacity thereof to conform to iiuctuations in the rate of inow to the basin, oat operated waste valves for controlling the capacity regulating means, the floats being located in the basin. and individual oat switches for starting and stopping the motors of the pumps, the two oats for one pump unit being set at a higher liquid level than those of the other pump unit, whereby one pump unit starts when the Y quid level reaches one level and itscapacity is increased from minimum to maximum upon the rise of the liquid level to a higher level and the other pump starts upon the rise o! the liquid level above said higher level and its capacity increases irom minimum to maximum upon continued rise of the liquid level above said higher level.

AUGUSTUS C. DURDIN, Ja.

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