US2471920A - Continuous press - Google Patents

Description

R. T. ANDERSON 2,471,920

CONTINUOUS PRESS May 31, 1949.

5 Sheets-Sheet 1 Filed Nov. 21, 1945 l I RAY/10100 7.' ANDERdO/V IQTFQRAMEKS May 31, 1 4 R. T. ANDERSON CONTINUOUS PRESS 5 Sheets-Sheet 2 Filed NOV. 21, 1945 A rramvsra y 1949- R. 'r. ANDERSON 2,471,920

CONTINUOUS PRESS Filed NOV.- 21, 1945 5 Sheets-Sheet 5 A T TOR/V573 May 31, 1949. R. T. ANDERSON 2,471,920

CONTINUOUS PRESS Filed Nov. 21, 1945 5 Sheets-Sheet 4 INVEN 70R RAY/1am: 7. ANOER'SON" Ann/957s y 1,1949. R. T. ANDERSON 2,471,920

CONTINUOUS PRES S Filed Nov. 21, 1945 5 Sheets-Sheet 5 L L2 L1 4 l N VE N T08 fi'A rnmvo 7. ANDERJ o/v arran'lvara Patented May 31, 1949 UNITED STATES:

237L920 CONTINUOUS BRES'S Raymond- T; Anderson: Lakewood; Ohio, assignor,

by mesn'e assignments, to The V. D. Anderson Company, Cleveland, -,Oh-io,w a-corporatiom of Ohio ApplicationNdvembef'Zl, 1945, Serial No. 630,057

3 Claims;- (Cl. 318434')' rial is --fed' bya feedmotor. In continuous screw presses; for example, a: feed motor drives the screw of"a h0pper feeder unit-which supplies material to the screw of an expeller-unit driven' by a second or-servi-ce motor. Such pressesare used for expr'essing liquld from a varietyofsubstan'ces, suchas oil from corngerms; cottonseed, nut meats" or other veg'e'table matter; or oil' from cracklings or other animal matter.

Presses operating upon some of these materials, notably corn= germ's'and crackli'ngs; are subject tonnexpected andra-pid' change 'inthe'fiber' content, the word fiber being used hereto denote'the solid material remaining after'the oili's expressed. When expressingcorn'germs, for example, mechanical difiiculties in' the separation of the corn germs from,thekernels'sudd'enly may cause'the delivery to the'pre'ss of a large" quantity of'whole corn kernels. Likewise; Whenexpressing crack li'ngs, the fiber content in the form of bone" and" bone fragments-suddenly may increase tremen dons-1y. The expeller operates on" a setting of the choke based" upon a"deflnite average fiber content and chosento-prod'uce maximum output and the desired efiiciency' in'ext'raction with both" motors loaded to"their rated capacities.

Irreither of the" cases mentioned above, when thefiber content of the-material suddenly increases, the motors;or-oneof'them may be come overloaded; Usually the hopper feeder motor is overloaded first and stops by operation" of its overload relays. But theservice motor which operates the eXp'eller, which-has not yet felt the efiect of the increased duty, keeps onoperating and may completely empty its barre1 o1 unload itsscrew within a matter of a'few' se'con'dstoa-couple of minutes; Consequently all re sistance to advance ofthennaterial disappearsby'reason -of loss' oi theplug-a t thechoke. When the overloadconditiori-is detected an'd the oper ator restarts the fee'd'mo'tor, it maytake from ten 'to fifteen: minutes toaga'in build up a plug andthus roduce the-necessary back pressure at-thechoke inorder to" again securemaximum capacity and efficiency in the extractionofoi1 orgrease.

On the other hand should the expeller motorbegin to 'overl'oa'd for any reason, such'--asamin 2: fluxfromthe hopper 'feeder too large or too rapid fonthe expeller to'handle', itis desirable tm porarily" to stop the hopperfeeder motor until" the expeller catches up and its load drops back- The present inventionhas for its object to overcome this' loss of time and efliciency' by the provisionof an improved automatic control system'g requiring nospecial attention by an operator, which promptly restarts thehopper feeder m'otor, should it stop; atleast early enough to avoid -or"prevent--such" loss of ba'ckpressure or resistance" to advance-of-the material in the" ex peller asmight reduce or 'impair e'lficiency; and in cases where theexpeller motor is oi'/er1oa'ding,- assoonasits load returns tonorrnal. Restarting of the hopper feedermotor takes places" after-a time interval whichis relatively short,' but still is suificient to insure such" reduction in load upon' the expeller motor as will enable its screw" to clear away some of the material in the expell'er" al'ieadof the hopper feeder and provide room or' space into which-the hopper feeder screw can" relieve itself. Theshort time interval may" be eithera predetermineddefinite period, time con trolled, ormay"bea variable" period dependent upon varying conditions, as will appear.

Anotherobject is to provide a control system of the character described in which upon stoppingof one oftwo asso'ciated'driver motors, the stopped motor'is'. restarted by means rendered efie'ctiv'e' up'on orbythe d'eenergization of one of it's circuits; either operating or controlling;

Still" another object is to control restarting of the stopped motor bymeansrendered operative or" effective upon reduction in the load upon the motor which continues in operation.

Finally, another object is to control restarting of a. stopped motorbyineanssensitive toan over F loaduponit, thus dispensing'with operator contfol for the-purpose Further objects of the invention in part are obvious'and" in part will appear more indetail I hereinafter;

where the load of one depends upon the duty of the other, for any reason, the drawings, solely for purposes of illustration and in no sense of limitation, show the invention applied for use in the control of the driving motors for a continuous screw press. The press chosen for illustration is of a common type, such as is used for expressing or expelling oil or other liquid from any solid material, either vegetable or animal, such as the materials before referred to. It includes a cooking vessel or conditioner H] from which the material to be pressed is delivered to a hopper feeder unit it, by means of which it is fed or delivered to an expeller unit l2.

The hopper feader unit includes a perforate barrel E3 in which rotates a screw [4 driven by feed motor l5.

Similarly, the expeller unit includes a perforate barrel it in which rotates a screw H driven by the expeller or service motor l8.

The axis of the hopper feeder screw I4 is vertical and the axis of the expeller screw I2 is horizontal. The hopper feeder element accepts the material delivered to it by the conditioner and forces it downwardly at gradually increasing pressure into the chamber of the expeller unit. During its travel downwardly through the hopper feeder the material undergoes some compression and extraction, oil escaping through the orifices of the perforate barrel.

The expressing operation is completed in the expeller unit, where the pressure applied to the material gradually increases to a maximum at the discharge end, where the material passes through the usual adjustable choke I9.

In a continuous press of this kind, maximum efficiency, as regards expulsion of oil or other liquid from the material being operated upon, is secured by proper adjustment of the choke so as to more or less restrict the outflow and apply resistance to advance of the material to the discharge. Proper restriction of the choke builds up back pressure resisting advance of the material in the second or expeller element, a resistance which is reflected back into the hopper feeder element so as to build up the pressure, but of course a lesser pressure, in that element, clear back to the inlet where the material enters from the conditioner.

In the operation of these presses the two motors are of course provided with overload relays or safety devices. When the expeller motor actually stops for any reason, as by actuation of its overload limit relay, an additional load or resistance of course is thrown back upon the hopper feeder element and its motor, the latter of which stops in due course because of overload. With such an extreme condition, or that kind of motor stopping, the present invention is not concerned. Such stoppage of both motors requires correction and restarting, usually by manual control, in the usual manner with presses of this kind.

According to the present invention, means 15 provided, in the control system for the motors, to take care of cases when the hopper feeder motor stops, as by reason of the sudden inflow to it of a quantity of material having an abnormally high percentage of fiber content, such as in the case of corn germs and cracklings as mentioned above, or cases where the expeller motor begins to overload, but to a value short of that which stops it by actuation of its overload limit switch. The restarting means for the hopper feeder motor may be of any suitable form, and operated or controlled by any suitable means, so long as it is sensitive to or set into operation by an abnormal or unusual increase in the fiber content (as above explained) of the work, and produces a restarting operation or effect after the lapse of a reasonably short period of time, a period not so long as to reduce the load on the expeller to a value where substantially all resistance or back pressure of the work is lost, but nevertheless long enough to permit such operation of the expeller as will partially unload it, with reduction of its motor load toward but not below a predetermined minimum value. A control system suitable for this purpose is shown in Fig. 2 of the drawings.

In Fig. 2, A represents the starting control panel; B the starting box or panel for the expeller motor, conventionally shown at 18; C a similar starting box or panel for the hopper feeder motor, shown conventionally at l5; and D a panel or subpanel for a time delay relay, to be described.

On the starting panel A are located a normally open starting switch S1, a normally closed stop switch S2 and an ammeter 2t, all for the expeller.

motor, and also a normally open starting switch S5, a normally closed stop switch S6 and an ammeter 2|, all for the hopper feeder motor l5.

On the starting panel B are located a normally open main switch S3 including three blades in circuit conductors 22, 23, 24 from the current leads L1, L2, L3, said switch being actuated by a coil 25 which also operates normally open maintaining switch S4. One of the leads, as 22, includes the primary 26, of a transformer, the secondary 26a of which is in circuit through the conductors 2?, 28 with ammeter 20. Each of the other two conductors as 23, 24, includes a coil 29 for actuating one or the other of two normally closed overload limit relay switches S10, S11, of ordinary form arranged to close immediately after opening.

The starting panel C for the hopper feeder motor includes a similar three-blade main switch S9 the blades of which are in the conductors 30, 3|, 32 to hopper feeder motor l5 from the leads L1, L2, L3, said main switch being actuated by coil 33, corresponding to coil 25, said coil also actuating the blades of a normally open maintaining switch S7 and a normally closed switch S8. The blades of switches S7, 88 are so harnessed together or arranged that in operation switch S8 opens after switch S1 closes, and vice versa..

One conductor 30 includes the primary 35 of a transformer, the secondary 35a. of which is in circuit with ammeter 2|. The other two conductors 3|, 32 each include a coil 34 for actuating one or the other of the overload limit relay switches S12, S13, corresponding to switches S10, $11.

On the panel D is located a time delay relay, conventionally shown at 36 and arranged to actuate the blade of switch S14, later to be referred to.

With the arrangement described, and as shown in Fig. 2, assuming both motors at rest and all switches and other devices in the normal positions shown, it is impossible to start the hopper feeder motor until the expeller motor has first been started. The reason is that no lead line to the starting switch S5 is alive. Consequently it is necessary to first start the expeller motor. This is accomplished by closing its starting switch S1, completing a circuit from L1, by way of conductor 22, conductor 31, starting switch S1, now closed, stop switch S2, conductor 38, overload relay switches S11, S10, coil 25, conductor 39 and conductor .24. to. La, thus energizing coil: [25. This promptly closes not, only. the main switch S2, thus energizing the expel ler motor, but :alsomain- .taim'ng switchv S4, thus establishing a maintaining circuit from L1 by way .of wire 40,. switch, 54, .now closed, conductor 4|, conductor 4.2, and then through stop switch S2 and wire .38 and .coil 25 :back to Lsxas before. It is now possible to remove the-finger from the start :buttonand still maintain the .main switch ;S3..clos.ed and thus keep motor 1-8 in operation.

It .is now possible .tostart thehopper feeder motor by closing its start button .55, with results asiollows:

Current fiowsfromlu by waypf conductor :40,

switch S4, conductor 4|, conductor 42, conductor 43;, .start switch S5,, nowelosed, stop. switch S6, conductor 44;, overload relay switches S13, S12, coil .33, conductor 45, and-conductor 46 to La.

Energization of coil 33 promptly closes main sWiQQh S9, thus completing the circuit through the leads .30;, 31, 32 tomctor I5 and startin the same, and, also closing switch S7 and; immediately aft r closin of. that switch, opening switch S8.

Switch S is ,now closed manually :to prepare the time delay relay :6. Switch S15, it should be stated, is a manually Qperated switch stable in either open or closed position. When said switch is. open, the automatic control :being described is ineffective, and the hopper feeder motor must be started by manual ,cont nol in {the manner beforedescribed. When said switch is closed the automatic restarting chanism is effective.

panel \C the bridging wire-4Q, shown in dotted lines and corresponding to "the same .num berecl wire on panelB, is: omitted, and the :corresponding contact ,ofswitch Sr: is connected by aconductor 41andconductor42 to the conductor 4,|-of the correspondingswitch :onpa-nel B. fIlhe other contact of switch .Sr-is {connected by a .con- ,ductor .48 to a contact of switch ,Sn, the other contact of which isconnectedby, .conductor =41;.to conductor 42 and the othercontactof switchSq.

Closingoj switch Sm. cgeates a maintaining circult for the coil 33, cor-responding to that for coil before described, andincludingconductors 44 and: 54., and stopswitchSi, while opening of switch S8 opens the circuit through conductors 5 0;and 5| to ,th e time delay relay 36.

The press is now in operation with 5. the various switches occupying th newpositions described, both motors opbra-ting aup toqrated capacity, as determined by motordesign andascontrolledby the overload limit relaM-switches :Sro. toSn in.- elusive.

If, now, for 34 13418915011, the. hopper feeder m0- tc-r suffers a sudden or abnormal increase in load, such as on account of a suddenincrease in the fiber content of the material being delivered to the hopper feeder screw, oneorthe other of the coils 34 on the hopper feeder motor. control panel willactuate and openits switch S1201 S13, or both. This deenergizes coil 33, permitting mainswitch S9 topromptly. open, and causing switch S1 to open, followed promptly by closing of switch S8.

Thereuponthe circuit to the time delay relay 35 is closed, current flowing as follows; From L1 by conductors 22 and 40, SWitQhZSLQSti-lL-ClOSGdQ, conductor 4|, conductor. to thepoint52, switch s (now closed), conductor 5,0, switch S15 (assumed to be closed) the coil,= .f time delay relay 3,6, conductor 51, conductor 45, conductor-46,;to L3. ont nuin when-tr inee de r lay is en.- ergized it goes through its; op ration. and

at the iend of anywsuitable period for which the relay is adjusted, say anywhere from five or ten seconds u to .two minutes or more, said relay closes the switchJSm. This switch completes a .circuit as follows: From'Li, by wayuof conductors 22-:and,;4||, switch S4, conductors .4'.| 4'2, conductor 49, switch S14, conductor .48, conductor 54, stop switch S6, conductor .55; overload relay switches .S1;,:S12,..C0i'1133*, and conductors. 45, 431110 L3. The leifectis toenergizevcoilnfl and produce a starting operation of motor L5 :byclosing .of the main switch. S9 .as before, ztogetherwith closing of switch S7. and subsequent opening of switch S8, zto.'establish. a maintaining circuit for the coil 133,, as before.

The parts have now-been restored to their operating positions, with both motors operating as before. Dhringathetime delay period, whateverit ave. been, 'when the hopper feeder motor-is at rest, the; expeller. motor. continues in operation, 0f course, the load upon said motor gradually decreases asthe .expeller, getsout .of the way some of the material under oing extraction in the expellerelement, relieving the back pressure on th hopper feeder element and providing space into which it can .dischargeiits overload of abnormal fiber content, when it, is restarted.

In the form (if-invention, just described, restarting of the stopped hopper feeder motor of course is sensitive to or ,set in, operation by an increase in. the load upon the hopper feeder moatop, as reflected into; thecontrol system by the overload relay switch ;S 12 or, S13. Two effects are producedby the overloadfirst; stopping of the hopper, feeder motor, and. second, energization ofnthe timedelay'.relay/ 364120 produce restarting after the lapse of a predetermined definite period in accordance with the setting of the time delay. relay. this earnamgement, therefore, the hopper feeder motor is always restarted after the lapsev of a predetermined definite period, during whichthe load on the expeller motor drops.

Under some circumstances it may be desirable to resta t-the hopper feeder motor after the lapse of a period of time which is more or less variable and which dependsupon some, other .controllling factor. F r-example, the delayperiod may be of undertermined valuebut renderedpdefinite in accordance with reduction in the load upon the still running expeller motor. Such an arrangement isillustrated in Fig. 3,;now to be described.

ThisarrangementdOes not require extended d-escriptiomsince most. of the circuits and parts are identical in construction, arrangement and manner. of Operation, with those illustrated and described in connection with Fig. 2. For this purpose, the more important. like parts and circuits, in the twoviews, have beenidentified with like reference characters, so that detailed description thereofv may be omitted. The differences between-the twoarrangements are as folows:

Restarting of the hopper feeder motor in this instance is produced by closing of a normally open switch S16, the conductors 60, 6|, for which areconnectedrespectively to the same conductors 44 before described. Switch S16 is mounted upona panel E. Its movable blade is connected to an armature 62 actuated by a coil :SQ- imaci Tacuit; the conductors 64, B5 of which are connected'to. thesecondary-Bfiof a current transformer, the primary 61 of which is in one of the leadwires, suchas 23, ofthe expeller motor cir- Quit; wWith,thisarrangement the system is set into operation in the manner before described, by successively closing the normally open start switches S1, S5, thereby first startin the expeller circuit and energizing its maintaining coil 25, and establishing a maintaining circuit therefor, and then starting the hopper feeder motor by similarly energizing its maintaining coil 33 and establishing a corresponding maintaining circuit therefor. Whenever the hopper feeder motor stops, for one of the reasons before described, such as a sudden influx of material of abnormally high fiber content, one or both of the overload switches S12, S13 opens, as before, deenergizes coil 33, and permits the main switch S to open, stopping the hopper feeder motor. The expeller motor continues to run, however, for a relatively short period of time, sufiicient to enable it to clear away some of the material in the expeller element, preparatory to restarting the hopper feeder unit. The length of the time period here depends upon reduction in the load upon the expeller motor to a definite low value, instead of an indefinite value, as before described.

The current transformer 66, 61, and the parts of the switch controlling relay 62, 63, are so constructed and arranged that normally, when the expeller motor is operating at rated capacity, or at any load above a predetermined value, sufficient current flows in the circuit 64, 65 to maintain the armature or plunger 62 in its switch-open position. But as the duty of or load upon the expeller motor decreases, the current flow in said circuit decreases until finally it is not suflicient to hold the plunger 62, which thereupon moves over to its other position, closing switch S10. Closing of switch S16 energizes a circuit (Fig. 3) as follows: From L1 by way of conductors 22, 46, maintaining switch S4 of the expeller motor circuit, still closed, conductor 4|, conductor 42, conductor 66, switch S16, now closed, conductor 6i, manually operable switch S (corresponding to and for the same purpose as switch S15 of Fig. 2) conductor 44, overload relay switches S13, S12, maintainin coil 33, conductor 45, and conductor 46 to L3.

The effect of closing this circuit is to reenergize coil 33, close main switch S9 for the hopper feeder motor, and energize its circuits to start said motor.

This arrangement, therefore, not only automatically restarts the hopper feeder motor, whenever it stops for the reason stated, and thus tends to keep the machine in operation without special attention by the operator, but it also provides a variable time delay period self-adjusting, as it were, to the nature of the particular material which has caused motor stoppage, in the sense that restarting of the hopper feeder motor depends upon definite reduction in load upon the expeller motor consequent upon stopping.

With this circuit, the expeller motor therefore can be kept at load automatically, based upon the load on the hopper feeder motor.

Preferably the relay 62, 63 is adjustable in any suitable manner to vary the number of amperes, or the load, desirably carried as a minimum on the expeller motor, or in other words, the load to which this control relay is responsive. The drawings (Fig. 3) show switch S10 as a conventional snap switch, held in either open or closed position by the yielding button 68, and moved toward closed position by the weight of armature 62 and the tension of loading spring 69 adjustable by screw 10, and toward open position by the pull of coil 63. By adjustment of screw 8 10, the relay may be made to yield and permit closin of switch $16 at any desired motor load, thus adapting the system to variations in material being pressed, or other changing conditions. This adjustment might be made once a month, or even oftener.

In both forms so far described, of course, the overload limit relay switches S10, S11, S12, S13 are of a usual or well-known form, opening momentarily upon increase in load to a predetermined limit, adjustable to respond to any desired limit value of overload, like relay switch S16, and arranged to close promptly, after a short time interval capable of variation by suitable adjustment, when the motor circuit is opened, ready for another operation.

The systems so far described automatically take care of any condition in which variation in the fiber content of the material causes stopping of the hopper feeder motor, restarting said motor automatically after a suitable time delay period, by means which is rendered effective upon or by deenergization of the hopper feeder motor circuit, or upon reduction in load upon the expeller motor consequent upon or caused by deenergization of the hopper feeder motor.

However, the invention is not limited to control by stopping or overload of the hopper feeder motor circuit, but is equally applicable when the condition requiring correction is an increasing overload in the expeller motor circuit. A control system thus functioning is shown in Fig. 4.

InFig. 4 all parts and circuits are the same as those in Fig. 3, with exceptions, as follows:

Here the maintaining circuit for the hopper feeder motor includes an overload switch S17 and its operating coil H, similar in all respects to switches S10, S11, etc., and their coils, and likewise adjustable as to load response and time interval in closing. The maintaining circuit extends from L1, by conductors 22, 40, switch S4, conductor 4|, conductor 42, switch S7, conductor 54, switch S17, stop switch S6, conductor 44, switches S13, S12, coil 33, conductors 45, 46 to L3.

Should the expeller motor circuit become overloaded, to the degree for Which coil H has been adjusted or set, switch S17 opens, thus deenergizing coil 33 and opening the main switch S0 and stoppin the hopper feeder motor. Of course the critical load to which switch I! responds is less than that to which switches S10, S11 respond. The consequence is exactly the same as before described, to wit, a gradual reduction in load upon the expeller motor until, finally, switch S10 is closed by the effect upon coils 66, 63, with consequent restarting of the hopper feeder motor, as before.

Fig. 5 shows still another arrangement for the same general purpose. Here another lead 24 to the expeller motor includes the coil 12 of a relay on panel F, the switch S18 of which again is included in the conductor 54 of the maintaining circuit for the hopper feeder motor. This relay may be of the same type and arrangement as those marked S10, S12, etc, and before described, but, of course, set to operate at a lower value of overload. Here again, an overload upon the expeller motor stops the hopper feeder motor and initiates a restarting operation therefor, dependent upon reduction in load upon the expeller motor, or, if the system of Fig, 1 is employed, upon the lapse of a definite time period.

The systems described supply full protection for two types of conditions, requiring control, one, where overload occurs in the hopper feeder mo-'- tor circuit, and, two, where it occurs in the expeller motor circuit.

In either case, the condition is corrected by stopping the hopper feeder motor and then starting it again, after overload has passed, by time delay for a suitable period, determined either by a timing device or by means sensitive or responsive to reduction in the expeller motor load. In the first case but one relay is required, while the second requires two, one to stop the hopper feeder motor and the other to restart it. Either system is satisfactory.

Other advantages of the invention will be apparent to those skilled in the art.

What I claim is:

1. Control means for a motor system which includes a service motor and a feed motor cooperating therewith and provided with a starting and maintaining circuit, comprisng an overload relay in the feed motor circuit, means responsive to said overload relay for opening the feed motor circuit and stopping the feed motor when overloaded, and means rendered effective by thus opening the feed motor circuit and effective upon reduction in load upon the service motor to thereby close the feed motor circuit and restart the feed motor.

2. Control means for a motor system which includes a service motor and a. feed motor cooperating therewith and provided with a starting and maintaining circuit, comprising an overload relay in the feed motor circuit, means responsive to said overload relay for opening the feed motor circuit and stopping the feedmotor when overloaded, and

10 time delay means rendered effective by thus opening the feed motor circuit and after the lapse of a period suflicient to reduce the load upon the service motor to close the same and restart the feed motor.

3. Control means for a motor system which includes a service motor and a feed motor cooperating therewith and provided with a starting and maintaining circuit, comprising an overload relay in the feed motor circuit, means responsve to said overload relay for openng the feed motor circuit and stopping the feed motor when overloaded, and means rendered effective by thus opening the feed motor circuit and responsive to predetermined reduction in load upon the service motor and thereby effective upon the feed motor circuit to close the same and thus restart the feed motor.

RAYMOND T. ANDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,301,966 Parkhurst et a1 Apr. 29, 1919 1,309,733 Hellmund July 15, 1919 1,395,089 Burhans Oct. 25, 1921 1,658,242 Hunter Feb. 7, 1928 1,742,434 Costello Jan. 7, 1930 2,249,736 Anderson July 22, 1941 2,306,810 Jones Dec. 29, 1942

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