Download pdf - Maintaining Vibratory Feeders

8/10/2019 Maintaining Vibratory Feeders

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Vibratory

Feeding

Systems

MaintainingVibratorySystemsTroubleshootingguideonmaintainingvibratoryequipment.


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MoorfeedCorporationADivisionofExecutiveAutomationSystemsInc.

1445BrookvilleWay,SuiteR,Indianapolis,IN46239(317)5457171www.moorfeed.com

Table

of

Contents

DETERMINETHEPROBLEM....................................................................................................... 1

WHENDOESTHEPROBLEMOCCUR?........................................................................................ 2

OBSERVETHESYSTEMRUNNING.............................................................................................. 3

LOOKFORBROKENSPRINGS.................................................................................................... 4

PREVENTIVEMAINTENANCE

....................................................................................................

5

LISTENTOTHESYSTEM............................................................................................................ 6

TOUCHTHESYSTEM................................................................................................................. 7

CHECKTHEELECTRICALCOMPONENTS.................................................................................... 8

SOLIDSTATECONTROLLER ...................................................................................................... 9

CHECKTHESENSOR................................................................................................................ 10

SENORS.................................................................................................................................. 11

UNDERSTANDINGYOUR

FINDING

..........................................................................................

12

SENSOR/RATEPROBLEM........................................................................................................ 13

NEWINSTALLATION............................................................................................................... 13

EXSITINGINSTALLATION........................................................................................................ 14

JAMS...................................................................................................................................... 14

TUNING.................................................................................................................................. 15

RESONANCETUNING........................................................................................................ 16/17

MECHANICALTUNING

............................................................................................................

18

MOUNTINGFEET.................................................................................................................... 19

AIRGAP.................................................................................................................................. 20

CHECKINGTHETUNING.................................................................................................... 21/22

SPRINGS................................................................................................................................. 23

MAZZASRULE........................................................................................................................ 24

NEMAENCLOSURES............................................................................................................... 25

TUNING101..................................................................................................................... 27/31

NOTES:............................................................................................................................. 32/34


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This information is intended to give the end user a working knowledge andunderstanding of the expected performance of a vibratory feeder bowl and its

related components. To give the user a complete education is beyond therange of this text. It is, however, intended to make known and to make clearany terms of procedures that may otherwise be unspecified or unfamiliar.

In the occasion conditions occurs w ith the feeding system that is unusual orconflic ting with normal operation, please attempt to use this in formation as a

guide to t rouble shoot and repair the system. If there is a situations thatcannot be corrected then you will need to contact a trained technician.


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Determinetheproblem

Talktotheoperators

Whatistheproblem?

Askthemachineoperatorstotellyouwhattheyseeastheproblem. Theoperatorsmaynotknowthe

extractnatureoftheproblem,butwillhaveobservedwhathappens. Oftenthereinsightwillguideyouto

therealproblem.

Bowl,track,control&stand

Whathappenswhentheproblemoccurs?

Sometimesafewquestionswillhelptheoperatorstofocusonthefeederproblems. Doesthefeedsystem

runatall? Doesthehoppercycleproperly;comeononlywhenthebowlisrunningandnotfeedpartsso

fastthatitoverfillsthebowl? Doesthebowlfeedslowerwhenfilledorruntoofastwhenempty?Isthere

anapparentjam? Dopartsspilloutofthebowl? Isthereahammeringsound? Dogoodpartsfalloffthe

track? Dounorientedpartsfeedthroughtothemachineorjaminthetrackorbowl? Arethepartsto

specification? Isthereflashontheparts? Hasthetrackbecomeslickfrommoldreleaseoroil? Isthe

trackblockedwithdirt,flash,chipsorotherdebris? Ifthesystemquitrunning,didithappengradually,or

allatonce?

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Whentheproblemdoesoccur?

Anothermachinestartingupmayoccasionadropinlinevoltage. Areductionorincreaseinairline

pressurecaneffectorientationonbowlsusingairjets. Aheavymachinecyclingintheareamaybe

transferringvibrationthroughthefloorthataffectsthesystemandgoesawaywhenthemachineshuts

down. Asecondvibratoryfeederrunningonacommontablecouldsetupaharmonicnodethatwould

affecttheperformanceofthefirstfeeder.

Howdoestheoperatorfixtheproblem?

Gettheoperatortodescribewhattheyhavetodotofixtheproblemorworkaroundit. Ajamthatoccurs

inthesamelocationandisreadilyclearedbyremovingthejammedpartwouldwarrantlookingatthe

partsandthetoolingatthatlocation. Jamsthatrequireunboltingsectionstoclearthejampointtowarda

slightlymoredifficultproblem. Iftheoperatorhastoremovethejamandclearalargesectionoftrack,

theproblemmaybecausedbyasectionofthebowlthatclosesorbecomesmoreconfined. Asingleout

oftolerance

part

could

also

cause

it.

Anoperatormayneedtohandplaceorientedpartsinthetracktokeepup. Heorshemayhavehelped

thepartsdownthetrackbypushingthembyhand.

Clearingjamswithpicks,pliers,screwdriversormetalobjectswilldamagethetoolingandcauseadditiona

problems. Itisbettertoprovidetheoperatorswithbrassorplastictoolstousetoclearjams.

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Observethesystemrunning

Lookforpartsflow

Turnonthefeedsystemandwatchitrunforaminuteortwo. Youarelookingtoseethatthepartsfeed

consistentlyupthetrack. Alsochecktoseethatthepartsflowatthesamerateandthevolumeupthe

internalhelixinthebowlandthattherearenodeadspotsorareasinthebowl.

Watchthepartsfeedingthroughtheexternaltooling. Dothepartsnegotiatethetoolingcleanlyandatan

evenrate?

Lookforobstructions

Makesurevibratingdrivebases,bowls,trackandhopperpansarenottouchinganymounts,brackets,or

otheritemsonthemountingplateortable.

Checktoseethatvibratingunitsareclearofthesoundenclosureandthesounddampingmaterial.

Ifthepartsarejamminginthetoolingorfallingoffthetrack,checktoseethatthetoolingisfreeofdirt

and/orscraporforeignparts,andifitisjammingbetweenthetrackschecktheundersideofthetrack

directlyabovethejamforweldspatterorothersnags. Alsochecktoseethatthepitchbetweenthetracks

isconstantandnotclosing.

Lookforinterference

Partsspilledoutofbowlmaybedampeningthedriveiftheyarewedgedbetweenthedriveandafixed

objectsuchasthesoundenclosure,springbanks,andunderthedriveunit.

Anotherplacetolookforinterferencecouldbemisalignmentbetweenthebowldischargeandtheinline

trackorothermeansofconveyance. Partshesitationorwedgingastheyconveyacrossthisgapcanbethe

sourceofthejamsandcausethelowrates.

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BiasAngletransfer

Adjustabletoolingnormallyshouldopenslightlyinthedirectionofflow. Toolingthatiswiderorhigher

whenthepartsenterthanwhentheyleavewillwedgeorcamlocktheparts.

Partsfeedingthroughthedischargeandotherareaswithoverheadconfinementshouldhavethe

confinementadjustedcloseenoughtokeepthepartsedgefromoverlapping. However,iftheconfinemen

issoclosethatthepartsundernormalvibrationhittheoverheadconfinement,flowthroughtheconfined

areawillbeimpeded.

Thecoilgaponthefeederisdirectlyproportionaltothebowl/inlinegap.

Lookforbrokensprings

Checkthebanksofspringsforbrokensprings. Mostspringsbreakintheareajustbeyondwheretheyare

clamped,justabovethespaceronthelowerclampandjustbelowthespacersontheupperclamps. Look

foracracklineontheouteredges. Anotherindicatorofcrackedorbrokenspringsisredororangedust

sometimeencirclingthebaseonthedrive.

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Springbank

PreventiveMaintenance

Overhaultheunit

Ifyouhaveanopportunitytooverhaultheunit,removethespringsonebankatatime,itisimportantto

removeonlyonebankatatimeastheotherbankswillmaintaintheproperpositioninsuringthatyou

maintainthedimensionaltargets,checkforcracksspringsbyholdingoneendofthespringandrapping

theotherendonametalplate. Thenchecktheotherend. Ifthespringiscracked,itwillbreakorsound

dull. Besuretocleanallrustandoilfromtheclampedareasofthespringsandtocleanthespaceraswell

Replacebrokenspringswithspringofthesamesizeandmaterial. Ifyoudonthaveaspringofthesame

thickness,youcanuseseveralthinnersprings. SeeMazzasRuleoftheSquareoftheNumeratorsto

estimatetherequirednumberofthinnerspringstouse.

LookforBrokenwelds

Checkthebowlweldsforcracksandbrokenwelds. Lookforweldedtoolingthatisvibratingoutofsync

withtherestofthebowl. Incoatedbowls,afteraperiodoftimethecoatingwillsometimescrackovera

brokenweld. Lookforredororangedust.

Lookforsolidcontact

Allthefeetonthestand,baseortableshouldbeinsolidcontactwiththefloor. Ifyoususpectthefeetare

notsolid,takeawrenchandcheckthem.Thevibratingdriveshouldbefirmlyattachedtothemounting

plate. Checktherubberisolationmounts(feet)fordeteriorationoftherubberandcheckthatthefeetare

securelybolted

to

the

riser

or

the

plate

and

to

the

vibrating

drive.

Then

pry

up

slightly

at

each

foot

to

see

iftherubbertometalbondissecure. Thebowlshouldbesecurelyclampedbyeachtoeclamp. Checkthe

torqueonthetoeclampsusingatorquewrench. Boltsonadriveunitshouldbetorquetothebolt

recommendspecification. Largerbowlwillhaveaboltinthecenterofthebowl,thisboltneedstobetight

waswellmakesurethecenterbowlhastheproperspacerbetweenthedriveandthebowlbottom,failure

todothiswillcausethedomeinthebowlbottomtoinvert.

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Listentothesystem

Listenformetaltometalhammering

Hammeringmeansthevibratingcomponentsarestrikingoneanotherorstrikingsomethingaroundthe

system. Checkthebowlandthetrackinterferenceandthetracktomachineinterface. Ifthehammering

comesandgoesthatisagoodindicationthatapartorscrapisgettingintothegapandcausingthe

hammering.Reposition

the

drive

to

open

the

gap

if

there

is

interface

interference

between

the

bowl

and

dischargeandtheexternaltrack. Movetheobjectbeingstruckifitissomethingaroundthesystem. Close

theinterfacegapifthehammeringiscausebypartsedgesgettingintothegap.

Coilgap

Checkthe

coil/armature

interface.

To

check

for

hammering,

insert

apiece

of

paper

between

the

pole

faces.Marksonthepaperindicatethegapistoclose. Resettheairgapbeingcarefulthatthepolefaces

areparallel. Theairgapshouldbeascloseaspossiblewithouthammering.

Listenforhunting

Huntingiswhenthevolumeortuneofthevibrationsseemstoberisingandfallingcyclically. Hunting

indicatesthefeederisundertunedoratresonance.

Listenforadiscordtone

Adiscordtoneisasteadyvibrationsoundthatwandersoff. Itcanbehigherorlowerinapitchthanthe

feedertone. Adiscordisasignalofnodeoraharmonic;somethingisflappingoutofsyncwiththerestof

thefeeder.

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TouchtheSystem

Touchthebowl

Feelforareasvibratingoutofsyncwiththerestofthebowl. Feeltheweldsinthearea. Apinchingof

thefingertipsisagoodindicatorofabrokenweldthatcannotbeseen.

Occasionally,an

area

of

tooling

will

appear

to

be

bouncing

parts

excessively,

and

yet

there

are

no

broken

welds. Ifwedgingapieceofwoodsuchasahammerhandlebetweenthetoolingandthewallorabrace

helps,thenthetoolingprobablyneedstobebracedorsupportedbetter. Excessivevibrationscanbe

causedbyotherdeficienciessuchasastandortablethatistoolightornotadequatelyrigid. Eliminatethe

otherpossibilitiesbeforeweldingadditionalbraces.

Touchthemountingplate

Feelforexcessivevibrationbeingtransmittedintoplatefromthefeeder. Ifthewholeplateseemstobe

vibrating,theplateisprobablytoothin.

Feelforareasontheplatethatarevibratingoutofsyncwiththerestoftheplate. Iftheplateisflexingin

oneortwoareasonly,thentheplatesupportneedstobestrengthenedinthatarea. Trywedginga2x4

betweenthefloorandtheplateintheareaofthetinning. Ifitcorrectstheproblem,thenreinforcethe

platesupportoraddajackleg.

Touchthebase,tableorstand

Feelthelegsforexcessivevibration. Heavywallsquaretubingisrecommendedforbuildingvibratory

feederbases,tableorstands. Itissuggestedthat21/2tubesforfeedersover10and4tubesfor

feedersover

21.

The

higher

the

feed

rate

the

more

substantial

the

stand

has

to

be.

Cross

bracing

betweenthelegsandsupportunderthemountingplateisrequiredforgoodperformance.

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Inspecttheelectricalcomponents

Checkthecoils

Onasinglecoilunit,ifthecoilisshortedortheconnectionisbrokenthefeederwontvibrateatall. Ifone

coilonthemultiplecoilunitisout,thefeederwilloperatebuthavesystemssimilartotuningorother

problems. Turnonthefeeder,takeasmallscrewdriver,paperclip,nailorothersmallironormildsteel

objectandtouchtheobjecttothecoilintheareaofthecoilarmatureinterface,iftheobjectisattracted

tothecoilitisworking. Donotexpectthistobeastrongmagneticpullyounormallygetfroman

electromagnet. Mostoftheelectromagneticenergyofthecoilisgoingintothearmaturebutwillgeta

weakattractionifthecoilisworking.

Thepolefacesofthecoilshouldbeascloseaspossibletothearmaturewithouttouching. Toocloseand

hammeringwilloccur. Passapieceofpaperbetweenthepoleface,ifthepapercomesoutmarkedthen

thepole

faces

are

hitting.

Thepapermarkedinoneareaonlyisanindicationthatthepolefaceisnotparallel.Resettheairgapto

eliminatethehammingbeingsuretosetthefaceparallel.

Checkthecontroller

Thereareseveraltypesofcontrollersusedonvibratorysystem,thetwomostcommonarevariableand

solidstatecontrol. Variablefrequencycontrolsarestartingtobecomepopularintheindustry. Whenyou

haveacriticalfeedingapplicationthatrequiresaclosecontrolorwerespringfatigue,fluctuatingvoltage

orload

is

causing

problems

an

amplitude

controller

with

afeedback

transducer

is

available.

Variabletransformercontroller

Alargeamountofthecurrentsystemshaveeitheravariabletransformerorasolidstatecontrol. A

variabletransformercontrolsthevoltageoutputtothecoil,sincetheyaretransformers,somearebuiltto

provideoutputvoltagehigherthanhigherthatthelinevoltage. Thevariabletransformercontrolisstable

andnormallyhasagoodrange. Problemoccurwhenthewindingwearthinandbreakorshorts.

Sometimethecontrolwillonlyworkfullon. Thisisoftenanindicationofabreakinthewinding.

A

variable

transformer

control

can

be

rectified

to

run

60

cycle

drive.

The

rectifier

puts

a

heavy

DC

componentintothetransformerthatwillquicklysaturateanormalsizedvariabletransformer,thereforea

25Amptransformerwouldtypicallybeusedtocontrolafeederthatwoulddraw10AmpsifrunningACor

nonrectified. Becauseofthecostforthemuchlargertransformers,mostrectifiedor60cyclesdriveuse

solidstatecontrols.

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Solidstatecontroller(phaseshift)

Solidstatecontrollerstodaytypicallycomewithaninternalswitchthatpermitthemtorunboth60cycle

(rectified,halfwaveorDC)and120cycle(nonrectified,fullwaveorAC)basedriveunits. The60cycleor

120cyclesreferstothenumberofvibrationspersecond. Wheninstallingareplacementsolidstate

controlmake

sure

the

internal

switch

to

A

for

120

cycle

and

D

for

60

cycles.

Thin

springs

3/16

or

less

andfiberglassspringsareusedon60cyclefeeders.

OneproblemwithSolidstatecontrollersisthattheysometimesareverysensitivetocontrol. Asmall

movementofthepotentiometerproducesalargechangeinamplitudeinthefeeder. Solidstate

controllerstypicallycomewithamin/maxtrimpotsontheboardtosetminimumandmaximum

amplitudeofthefeederandusesthepotentiometerontheoutsideofthecontrollertocontrolthe

amplitudeofthefeederbetweentheminandmaxrange,thusgivingtheoperatorfinercontrol. The

minimumpot

normally

is

set

so

that

the

parts

just

start

to

move

when

the

external

potentiometer

is

set

to

zeroandthemaximumissettothehighestamplitudedesiredorrecommendedwhentheexternal

potentiometerissetat100%thehighsettingshouldnotcausethecoilstohammer.

SolidStateControls

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Inspectthesensors

ThepurposeofthePhotoElectricsensoristoturnthebowlonandoffsoastomaintainafulllineofparts

inthetrackandnotallowthepartstobackupintothebowlandjamormisorientparts. Sensorswill

either

be

controlled

by

a

Programmable

Logic

Controller

(PLC)

or

have

a

programmable

logic

card

built

intothemodule.WhenthefeedersystemisusingaPhotoElectricsensortomonitorthegravity,conveyoror

inlinetrackandisnotbeingcontrolbyaPLC,thenitmustbesetorprogrammedfortheapplicationitis

beingused. Theswitchwillveryseldomoperatecorrectlyrightoutofthebox.

Thefirststepinsettingthesensoristomountthesourceandthereceivercablestoanonvibratingor

movingbracketandpositionthemsotheyarefocusedateachother. Applypowerontheproberleadsof

thesensor. Ifthesensordoesnottriggerorfunctionthenturnthesensitivityup,orusuallyclockwise,unt

thesensorswitchesstateorfunctions. Nextmovethepartortargetbetweenthefocusedcables. The

switchshouldnowreturntoitsdefaultstate. Thisisalightoperatecondition. Ifthisdoesnotoccurthen

thebeam

is

passing

around

or

through

the

target.

The

sensitivity

needs

to

be

reduced

and

or

some

portionofthebeamneedstobeblocked.

Optionaldescription:

Mostsensorscanbesettooperateeitherlightordarkoperate. Thismeansthatifthelightbeam

(whentheswitchispowered)ispassingfromtheemittercabletothereceivercableuninterruptedandthe

switchisfunctionedortriggeredthenthisisalightoperatecondition. Whenthebeamisinterruptedthe

switchreturns

to

its

default

or

non

functioned

state.

The

device

that

is

being

functioned

inside

the

moduleisusuallyasetofcontacts. ThesecontactsareeithernormallyopenedNOornormallyclosed

NC. Inthedarkoperatemodethelogicorstateforthecontactsarereversedaswellastheonandoff

delaytimers.

Asthepartsfeedpastthesensor,theoffdelayneedstobesetsotoallowtimeforaparttomoveinto

thebeamandexitthebeamwithoutactivatingthesensor. Thisisattainedbyincreasingthetimer

potentiometer. Itisgoodpracticetoallowfortheoccasionalslowerparttobethestandardratherthan

thefastermovingpart. Additionalstorageofthepartspastthesensorcanbecreatedwiththisfunction.

Takecare

when

adding

time

on

this

timer

because

ifthis

timer

has

too

much

time,

indiscriminately

applied,thepartscanbackupintothebowlandcauseproblems.Thenextfunctionthatshouldbe

programmedistheondelay. Thistimerusuallyissettoallowforsomeofthestoredpartsinthetrackto

exitbeforeturningthebowlonimmediatelyafterthepartsfeedawayfromtheblockingsensor. This

timercanstarvethetrackiftoomuchtimepassesbeforeturningthebowlbackon.

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PhotoSensor

Aproximitysensorworkssimilartoaphotocellsensor.

Thepaddleswitchorproximitysensorcontrollingthehoppershouldbesettomaintaintheproperlevelof

partsinthebowltoensureagoodfeedrate. Thehoppersensorshouldbewiredinserieswiththebowlso

itwillrunonlywhenthebowlison. Otherwise,iftheswitchweretocallforparts,justasthebowlturns

off,the

hopper

would

overload

the

bowl.

The

flow

of

the

feeding

parts

ensures

that

acorrectly

set

paddle

orsensorwillsensethepartslevelaccurately.

Paddleswitch

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Understandyourfindings

Donoharm

Ifthefeederisstillunderwarrantyorifyouareuncertainoftheproblemorthesolution,callthe

manufacturer. Mostmanufacturersvoidwarrantyifsomeoneotherthantheirrepresentativeworkson

theequipment.

Itemsyoucontrol

However,makesureyouhaveeliminatedthoseunderyourcontrol.

1. Parts. Arethepartsthesameandwithintolerance? Aretheymadeofthesamematerialand

ascleanasthepartssenttothemanufacturerforbuildingtheequipment?

2. Installation. Istheequipmentinstalledcorrectly? Isthetoolingadjustedcorrectlyforthepart?

3. Powerandair. Isthesystemgettingadequatepoweratthecorrectvoltageandcleananddry

airattherecommendedpressure?

Itemsbeyondyourcontrol

Ifitsunderwarrantyandyouhavecoveredallyourbases,thencallthemanufacture. Donotmachine,

grindorweldafeederunderwarrantyunlessauthorizedtodosobythemanufacturer.

PoweronNovibration

Electricalproblem

Thesystemhaspowerbutthefeeder(s)isnotrunning,turnthepoweroff,checkthefuse(s),checkthe

powercordfromthecontroltothecoil(s)forashortorbrokenwire,checkthelineforcontinuitytothe

coil(s),checkthecoil(s)toseeifithasbeenshortedout,repairanyproblemsandturnthepowerbackon.

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Sensorproblem

Thesystemhaspower,thelines,fusesandthecoilsallcheckout,yetthevibratorybowlstillwontcome

on. Suspectthesensor. Cleanthephotoopticsandchecktherealignment. Ifthesystemstillwontrun

checkthesensitivityadjustment. Markornotetheadjustmentpriortomovingitsoyoucanreturntothe

settingifnecessary.

Check

the

switch

for

continuity.

Repairorreplaceanydefectivecomponentsandturnontheunit.

Ifthesensorchecksouttheproblemisprobablyintherelay. Therelaymaybeeithersolidstateorcontac

type. Replacetherelayifnecessary. OnsystemwithaPLC,ifallelsefails,checktheprogram.

Rateproblem

Feederwontkeepup

NewInstallation

Trytuningdowntheamplitude.Therheostatorpotentiometersettingrecommendedbythemanufacture

isnotcastinstone. Sometimesslowingdowntheunitproducesmorethroughputoforientedparts.

Checkoutthesystemwiththepartsthatwereusedtobuildthefeedsystem. Ifthesepartsrunatrate,

lookatyourproductionparts. Thepartsmayhavebeenchangedslightlyindimensionormaterial

composition. Theymaybefromdifferentsuppliers,orthetolerancesareatthehighendwherethe

samplesused

to

build

the

bowl

where

at

the

low

end.

The

forming

tools

used

to

make

the

parts

may

be

wearingandnowthepartshaveburrsorsmears. Plasticpartsmayhavemoldreleaseandmetalparts

moreoil.

Ifnecessarycleanthebowlandtheparts,orreplacetheparts,andchecktherateagain.

Whenbuyingafeedsystem,itisrecommendedthatyousupplypartsfromallvendorstothefeeder

companytobuildandtestthefeeder. Alsosupplyadrawingwithtolerancessotherearenosurprises.

Iftheoriginalpartsareusedtobuildandtestthebowlwontfeedatrate,thenitisprobablythe

installation.Make

sure

the

stand

is

solid

to

the

floor

and

anchored

if

anchors

are

required.

Make

sure

the

flooritselfissolidandnotflexing. Ifthefeederisonyourtable,makesurethetableisnotflexing.

Ifnecessaryreinforcedeficientareas.

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ExistingInstallation

Ifthesystemhasbeenmoved,checktheinstallationasdetailedinnewinstallations.

Ifthefeedrateseemstofadeovertimeandtheoperatorhastokeepincreasingthepowertothefeeder,a

springmayhavebrokenorthespringsmayhaveworkedhardenedandchangethetuning. Ifthereareno

brokensprings,

remove

aspring

or

exchange

at

least

one

spring

with

athinner

one.

Jams

Jamsinthebowl

Ifthejamsarecausebybadorbrokenpartsremovethepart.

Ifthejamsoccurbetweenthetracksinsidethecowlinapproximatelythesamearea,checktheunderside

oftheuppertrackforweldspatter. Fileorgrindtheseoff. Ifthereisnospatterthenreducethequantity

ofpartsinthebottomofthebowltooneortwolayersdeep. Ifthisdoesnotresolvethisissuethereare

othermethodssuchasskirtingthebowlorremovingliningbutnormallyneedstobedoneatthe

manufacturerfacility.

Ifthejamsoccurinthetooling,checkthejamstoensureitiswithinspecification,ifitisagoodpart,check

tosee

the

tooling

doesnt

close

in

the

direction

of

flow.

Reset

adjustable

tooling

to

open

in

the

direction

offlowortobeparallelfromendtoendwhennecessary.

Beforeyoumoveorgrindtoolingtothebowl,besureyouconfirmthatthesensorsareworkingasthey

shouldandthatjamsarenotcausebybackpressureinthebowl.

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Tuning

ElectricalPower

Vibratoryfeedersaretunedwhenthebowlandbaseresonateatornearthefrequencyofthepower

source. Electromagneticcoilsaremostoftenusedtoexcitethetunedtwomasssystemofthebowland

base,however,anairvibratororanothersourceofenergycouldbeusedaswell. Electricalcoils.Normally

operateoffasinglephaseofthepowersupply. Thepowersupplyfrequencywouldnormallyoperateoffa

singlephaseofthepowersupply. Thepowersupplyfrequencywouldtypicallybe60HertzintheNorth

Americaand50HertzinEurope.

StraightACorRectifiedCurrent

Feedersusing

astraight

AC

power

supply

operate

at

7,200

vibrations

per

minute

(VPM)

on

60

Hertz

currentandat6,000VPMon50Hertz. At60Hertzthefeedercoilreceivesapositiveelectricalimpulsethe

first8.33millisecondsofthe16.66milliseconds. Feederamplitudesarethatofrectifiedfeedersofthe

samesize,however,sincethevibrationsperminutearedoubledmanypartsfeedatthesamerate.

Orientationcanbeaccomplishedusingfinerfeaturesontheparts,duetotheloweramplitudeofthe

bowl.

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Arectifiedinthepowersourceblockseitherthenegativeorpositivecomponentofthesinewave. The

feederoperatesat3,600vibrationsperminuteon60Hertzcurrentandat3,000VPMon50Hertz.Whena

rectifiedcontrollerissupplied,thevibratoryfeederhas8.3millisecondsbetweenpulsesofcurrenttothe

coil;therefore,greateramplitudecanbeachieved. Thinnerleafsprings1/16to3/16thickorgenerally

usedtotunearectifiedfeedersincethethinnerspringsaremoreflexibleandcanbebettertoleratethe

higheramplitude.

ResonanceTuning:

Theresonant

frequency

of

afeeder

is

the

frequency

measured

the

instant

after

thefeederisshutofforatwhichitresonateswhenstuckwithahammer. Itisthemostefficientfrequency

ofanytunedtwomassvibratoryfeedersystem.

ResonanceTuningAbovethePowerLineFrequency

Feedertunedtoaresonantfrequencythatishigherthantheelectricalservicegenerallyperformbetter

undervaryingloadandonbasesthatarenotasrigidastheymightbe.Bothloadsandalessthanrigidbase

willlowertheresonantfrequencyofthevibratorysystem. WhenthefeederistunedHightheadded

loaddrivesthefrequencyuptheefficiencycurvetowardthepowerlinefrequency. Theresultisthefeede

feedsbetterunderload. Astheloadlessensthefeedertuningbecomesstifferthuscompensatingforthe

lighterload. Hightuningalsohelpscompensateforalessthanrigidmountingplatform.

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ResonanceTuningbelowthePowerLineFrequency

Whenafeederistunedsothatitsresonancefrequencyisbelowthepowerlinefrequency,thefeederhas

notoleranceforloadand/oralessrigidmountingplatform. Anincreaseinthequantityofpartsinthe

feederlowersthetuningofthesystem. Theincreaseloaddrivesthefrequencyfurtherdownthepower

curveawayfromthepowerlinefrequency. Theresultisafeederthatperformspoorly,runningslow

underloadandspeedingupexcessivelyasthebulkofthepartsfeedout.

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Feedersarenormallytunedbyaddingorremovingsprings.Masscanalsobeaddedtoorremovedfromthebowl,

trackorpanand/orthebasedrive.

Themostcommonusedtochecktuningissimplytoloosenaclampingboltononeofthebanksofspringsand

observethefeeder. Amorereliablemethodistotunewithavariablefrequencycontroller.

MechanicalTuning

Ifavibratoryfeederisnotfeedingwell,checkthefollowing:

MountingPlatformBesurethestandortableissolid,rigid,levelandallfeetareplantedfirmlyto

thefloor.

FeederToeClampsandCenterBoltsBesurealltoeclampsaretightandthebowlisseated

properlyinthetoeclamps. On18andlargerbowls,besurethecenterboltistight(makesure

thatthespacerbetweenthebowlbottomandthetopofthecrossarmisinplacefailuredosowill

resultinthedomeofthebottombeingdamage).

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Toeclampattachesbowltodrive

RubberMountingFeetChecktherubbermountingfeetbypryinguplightlyunderthebasedriveatthe

feetandlookforseparationbetweenthefootandthebase,ortherubberandthemetalmount. Ifsee

separation,youhavetotightenthefoottothebaseorreplacethefootitself.

RubberMountingFeet

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CoilChecktoseeifcoil(s)isworkingbyturningontheunitandplacingaferrousobject,suchasa

screwdriver,closethecoilairgap. Ifthemetalisdrawntothecoil(s),itisworking. Donotexpectthisto

beastrongattraction.

CoilAirGap

AirGapChecktheairgapbetweenthecoilsandthearmature. OnanACunitthegapshouldbe.015

.020on4.5and6feedersand.025on8through24feeders. Onallrectifiedunitstheairgapshould

beatleast.060anddependingonthesizeofthefeederupto.100. Thegapshouldalwaysbeevenand

theparallelacrossthefaceofthecoildonotsetthecoilarmatureairgaptoocloseasthepolefaceswill

hammer.Try

to

set

the

air

gap

as

close

as

possible

and

still

not

hammer

when

full

on

or

when

starting.

Thewiderthegapthemoreamperestheunitwilldraws. Checktheairgapbyturningtheunitfullonand

passingapieceofpaperthroughthegap,ifthepaperismarked,thegapistooclose.

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CheckingtheTuning

Checkthetuningbyturningontheunitandadjustingthecontrolsothatthepartsjuststarttomoveinthe

bowl. Breakoneboltlooseononebankofspringswhileyouobservethepartsinthebowl. Ifthefeeder

speedupandcontinuestodosoasyoucontinuetoloosenthebolt,thefeederisovertunedandthe

resonancefrequencywillhavetobedropped. Thisisthemostcommontuningproblemasthesprings

tendtoworkhardenovertime. Tunetheunitbyremovingaspring,orbyreplacingonewithathinner

spring. Ifthefeederslowsdown,thedriveisundertunedandaspringorspringswillhavetobeadded.

Whenyouaretryingtoachievetheproperresonantfrequency,addthespringorspringtothebankthat

hasthefeweramountson,itwisetotrytoeventheamountofspringperbank,ifallisthesameaddone

atyourease.

Ifyouhaveanareathathasexcessivebounce,anadditionalspringorspringsaddedunderthatpartofthe

bowlwilltendtoreducethebounce. Springscanberemovedfromonebank,whereadditionalbounce

mightbeneededorwillnotaffectorientationorfeedrate,toanotherbankunderanareaofconcernin

thebowl.

Generally,whenthenumberofspringsrequiredcannotbesplitevenlyamongallthebanks,theheavier

springbankshouldbeatthecoils. Itisgoodpracticetoputthethickerspringstowardthecrossarmwith

thethinnerspringsawayfromcrossarm.

SpringBank

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SlidingSpringClamp

Checktuningbylooseningonespringclampingbolt,iftheunitspeedsup,removeaspring,andifitslows

downaddaspring. Takecaretousethecorrectlengthofbolt(s)whenchangingsprings. Onsomeolder

drivestheboltmaybottomoutagainstthepolefacemount,ifitistoolongitwillnotclampthesprings

tightcausingatuningissue.

Onthe8upto15unitstheclamp(s)canberaisebutonlytothetopofthepost. Totune,raiseorlower

theseclampsinsmallincrementsastheforceofthespringsincreasesordecreasesbythecubeofthe

length.

Theunitisproperlytunedwhenthefeederspeedsupasyouinitiallybreaktheboltlooseandthenslows

downasyoucontinuetoloosenthebolt.

Torqueallbolts,especiallyspringandtoeclampbolts,toatleast80%oftheirratedtorque.

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Springs

Springsconnectthefeederbasemasstothebowl,trackorpanmass. Everythingattachedtothetopof

thespringispartofthebowl,trackandpan. Thebowl,trackandpanareaportionofafeedsystemthatis

supposestovibrate. Themuchheaviermassofthedrivebase,plateand/ortablecontributetohowwell

thevibrationistransferredtothebowl,trackorpan.

VariousSpringsSizes

Springscomeinvariouslengths,widths,andthicknesstomatchtherequirementsofthevibratoryfeeder.

Springsaremadefromhardensteelorfiberglass. Thickersteelspringsandupareusedonfullwave

units,rectifiedorhalfhaveunitstypicallyuse1/8steelspringsorthinnerasthethinnerspringshandle

thegreateramplitudebetter.

Allfeederswithfiberglassspringsarerectified.

SpringForce

Springforceisamountofforcerequiredtodeflectaspringandtheamountofloaditwillreturnwhen

deflected. Springforceisanexpressionusedtodescribethestiffnessofaspring. Afullwavefeeder,

becauseit

has

ashorter

time

of

cycle,

requires

about

4times

the

spring

force

to

return

the

same

amount

ofmassasarectifiedorhalfwavefeeder.

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Mazzasruleofthesquareofthenumerators

Ruleofthumbusedtoestimatespringforce

Whentryingtoestimatespringforcerequiredforagivensituation,MazzasRuleoftheSquareofthe

Numeratorsworkswellinmostsituations.

Thespring

force

or

stiffness

of

agiven

spring,

for

afeeder,

can

be

compared

to

other

springs

by

using

MazzasRuleoftheSquareoftheNumerators. Estimatingspringsrequiredtoreplaceaspringofa

differentthicknesscanbedeterminedbythefollowingmethod.

1. Measurethethicknessofthespringtobereplacedinthe16th

ofaninch.

2. Squarethenumeratorofthatfraction.

3. Measurethethicknessin16th

ofaninchofthespringsavailabletoreplacethe

brokenspring.

4. Addthesquaresofthenumeratorsofthereplacementsprings,tomatchascloseas

possible,thesquarenumeratorofthebrokenspring.

Forexample,ifa3/8thickspringbreaksandyoudonothaveanother3/8springtoreplaceit,two

thickspringsandone1/8spring(orfour3/16thicksprings)willreplaceit. Besuretoputspacer

betweeneachspring.

Tocalculatethespringforceintheexample

Convert3/8tothecommondenominator6/16

Squarethenumerator62=36

Aspringthatis6/16(or3/8)thickhasaforcevalueof36

Convert1/4tothecommondenominator 4/16


Aspringthatis4/16(or1/4)thickhasaforcevalueof16

16+16=32.Twospringsarenotquiteenough

Convert1/8tothecommondenominator 2/16


16+16+4=36

Two1/4

thick

springs

and

one

1/8

thick

spring

have

acombined

force

value

of

36,

equal

to

one

3/8

thickspring.

Four3/16thickspringsalsoequalone3/8thickspringinforcevalue.


9+9+9+9=36

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NEMAENCLOSURES

NOTE: ThismaterialisderivedfromNationalElectricalManufacturersAssociationforElectrical

Equipment,NEMA250,EnclosuresforElectricalEquipment(1000VoltsMaximum),copyright

1997byNEMATheinformationcontainedhereinisnotintendedtobecompletedescriptions.

Referto

NEMA

Standard

250

for

complete

details.

TYPEApplication&Description

Type1: Appliestoenclosuresthatareintendedforindooruseprimarilytoprovidesomeprotection

againstcontactwiththeenclosedequipmentorlocationswherenontypicalserviceconditionsdonot

exist.

Type3:

For

Enclosures

that

used

for

outdoor

use

primarily

to

provide

some

protection

against

windblowndust,rain,andsleet:resistantandundamagedbytheformationoficeontheenclosure.

Type3R: Forenclosuresthatareusedintheoutdoorsprimarilytoprovideaprotectionagainstfalling

rainandsleet;undamagedbytheformationoficeontheenclosure.

Type4: Forenclosuresthatareusedinindoororoutdoorusetoprovideaprotectionagainstwindblown

dustandrain,splashingwater,andhosedirectedwater;undamagedbytheformationoficeonthe

enclosure.

Type4X: Forenclosuresthatareusedforindoororoutdoorusetoprovideaprotectionagainst

corrosion,windblowndustandrain,splashingwater,andhosedirectedwater;undamagedbythe

formationoficeontheenclosure.

Type6: Submersibleenclosuresaresuitableforapplicationwheretheequipmentmaybesubjectto

submersion.Theenclosuredesignwilldependuponthespecifiedconditionsofpressureandtime.The

enclosurewillalsoremainundamagedbytheformationoficeontheenclosure.

Type9: Hazardouslocationenclosures ClassII,GroupE,ForG.Theseenclosuresaredesignedtomeet

therequirements

of

the

Canadian

Electrical

Code

Part

Ifor

Class

IIIt

hazardous

locations,

and

CSA

codes

section18ClassIIGroupE,f,andG.

ClassIIGroupE atmospherecontainingmetaldust.

ClassIIGroupF atmospherecontainingcarbonblack,coal,orcokedust.

ClassIIGroupG atmospherecontainingflour,starchorgraindust.

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Type12: Forenclosuresthatwilloperateprimarilyindoors.Industrialapplicationsaretypicalwherethe

enclosuresareoiltight.

Type12K: Theseenclosuresthatwilloperateprimarilyindoorsandhaveknockouts,Industrial

applicationsaretypicalwheretheenclosuresareoiltight.

Type13: Thecoverisheldinplacewithscrews,boltsorothersuitablefasteners,withacontinuous

gasketconstruction.Thefastenerpartsareheldcaptivewhenthedoorisopened.Therearenoholes

throughtheenclosuresformountingorattachingcontrolsinsidetheenclosure,andnoconduitknockouts

oropenings.Mountingfeet,brackets,orothermountingmeansareprovided.Theseenclosuresare

suitableforapplicationtomachinetoolsandotherindustrialprocessingmachineswhereoil,coolants,

water,filings,dustorlintmayenter,seepintoorinfiltratetheenclosurethroughmountingholes,unused

conduitknockouts,orholesusedformountingequipmentwiththeenclosure.

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Tuning101

TuningaStorageHopper

1. Fillthehopperwithparts.

2.

Checkthe

power

supply.

3. Checkthecoilgap,setat.040to.050andparallel.

4. Setthepaddlearmornoncontactswitchsothatthehopperwillsupplythebowlfeederwithone

totwolayersofparts.

5. Checkthetuningasfollows:

Whenthelowerspringboltisloosenedandthepartsinthehoppertrayceasemoving,the

hopperisundertuned. Aspringshouldbeaddedtooneofthespringbanks. Afterthe

springhasbeenaddedandtheboltstightened,turnthehopperandloosenthelowerbolt

again. Ifpartsmovementspeedsupslightlyastheboltisloosened,thehopperisthen

tuned.

Ifpartsmovementincreasessharplywhenthelowerboltisloosened,thehopperisover

tuned.Removeonespringandtightenthebolts. Repeatthisprocedureuntilparts

movementincreasesslightlyasthelowerboltisloosened.

PrecisetuningfrequencymaybemeasuresusinganAmplitudeFeedBackcontroller.

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Tuning101

TuningaInlineDrive

1. Placesomepartsinthetrack.

2. Checkthepowersupply.

3. Mounttheinlinebaseplatefirmlyinordertochecktuning.

4. Checkthecoilgap,setat.020to.025andparallel.

5. Checktomakesureallboltsaretight.

6. Checkthegapbetweenthebowlandinline,minimumof.020clearances.

7. Turnthecontrollertoasettingofapproximately35%to45%ofinputvoltage.

8. Loosenonescrewoneitherofthetwofrontspringsapproximatelyaturn. Iftheunitspeeds

up,itisovertuned. Removeonespringandreplacewithathinnerspring,repeatuntilunitslow

downwhenthescrewisloosenedaturn.


Note:Atracklengthshouldbemountedonthetopbaroftheinlinebasedriveunitasfollows:

Atracksectionwhichislongerthanthemountingbarshouldbemountedaccordingtolength. On

thereceivingendorentranceitshouldoverhangthemountingbaraminimumof1. Onthe

dischargeendorexititshouldoverhangaminimumof2. Theoverhangratiobetweenthe

receivingandthedischargeendsofthetrackshouldbe2to1minimum.

28

Tuning101


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TuningaBowlDrive

1. Place1to2layersofpartsinthebowl.

2. Checkthepowersupply.

3. Mountthedrivebaseplatefirmlyinordertochecktuning.

4. Checkthecoilgap,startat.060forwaveand.030forfullwave,anditmustbeparallel.

5. Checktomakesureallboltsaretight.

6.

Checkthat

all

springs

are

separated

by

spacers,

top

and

bottom.

7. Checkthetuningbyturningtheunitonandadjustingthecontrolsothepartsjuststarttomovein

thefeeder,breakoneboltlooseononeofthespringbankswhileyouobservethepartsinthe

feeder,ifthefeederspeedsupasyouloosenthebolt,thefeederisovertunedremoveorlower

theclamponthesmallerdrive,ifthefeederslowsdownthenitisundertunedandaspringwill

needtobeaddedorraisetheclamponthesmallerunit,themostcommontuningproblemasthe

springtendtoworkhardenovertime.


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Tuning101

Definition: SpringForceTheamountofforce(2Masssystem=Drive+Bowl).

Requiredtodeflectaspring&theamountofloaditwillreturnwhendeflected.

MazzasRuleofthesquareofthenumeratorsmakesaconversionlistofallspringinchartform: 1/16=1

1/8=4

3/16=9

=16

5/16=25

3/8=36

ExplainResonantFrequencyThemostefficientfrequencyofany.

Prefertuning1.5to3H=aboveexistingpowerfrequency.

Example:

Rectified60cycles=61.5to63

Rectified50

cycles

=51.5

to

53

Example:

ST.AC60cycles=121.5to123

ST.AC120cycles=101.5to103Hertz

Explainrectifiedvs.Fullwave UsePixofSineWaves

Termstodefine:Huntingdiscordtone

Explain: Whyspringplacementiscriticaltoperformancei.e.livebankdeadbank.

Fundamentals: Relatingtoorproducedbythelowestcomponentofacomplexvibration.(Definition

MarionWebsterCollegiateDictionary)

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Defineundertunedvs.overtuned

Procedurefortesti.e.,whysystemicorderisimportanttorevealthetuningproblempix#2 #1toshow

simulationofreducingspringforcenaturally.

IncludespringR.C.=28&why?Reliableteststandards

MORENATURAL

Simulationforreducingspringforce

Addnotes: Mosttuningmanualssaythatthecoilgapdoesnotaffecttuning! Thoughtrue,itisan

ambiguousstatement,duetoopeningthegaptoowideorclosingittooclosewillbothresultindiminished

powertothesecondarymass.(Thebowl)

Track: 1/32/3ruleinline

Demonstratewithstrobethemechanicalmovementofcoilassemblyetc.useheatsensortoprove

ordisprovecoilgaptheory.

Additionalnotes: Springspacerimportance,cockedlugorbentspringscancreatepreloadedcondition

andbreakspringsthickestonefirst.

Strobewillalsorevealacrackedspringandshouldbeusedafterallboltsarecheckedforproper

torqueandcoilgaps.

1.)Boltstretchorseatafterseveralmonthsofrunningandcancauseundertonecondition.

2.)Mountingfeetareakeytocontroloftheprimaryenergymassplatetheyshouldbeheightmatched

anddurometershouldbeequal.

3.) Ifmassplateisinadequatetheentirejobwillturnonthetablemasscanbeaddedtotheplate,but

it

will

reduce

the

frequency

and

you

will

add

springs.

(see

marked

page

on

good

rules)

4.) Testcoilgapifhammeringwithpaper.(Onlargeunitsit ishardtoknowwhichoneistooclose)

5.) Sometimewhentheunitistunedpartstillwontfeedtrydifferentpartsiftheyfeedthebowlneed

helpviaamechanicaltoothXsandingthetrack,Brushlonetc.

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Notes:

32


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Notes:

33


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Notes: