ELNA Transforma - Automatic Thread Release

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16. Automatic Thread Release
TheSupermaticandTransforma,uptoSerialNo.527,625,
hadtwosimpleStopSpringstoholdthestationaryportionof
theshuttleinplaceandforthereleaseoftheupperthread.
TheShuttleBeaksitsbetweentheStopSpringswithacertain
amountofclearance.Astheshuttlerotates,theShuttleBeak
comestorestagainsttheStopSpringpreventingthetwo
assembledguardringsfromrotating.
ThethreadmustforceitswaybetweentheStopSpringand
theShuttleBeakpressingagainstit.Thisslightdisplacement
oftheShuttleBeakinducesadditionaltensionintheupper
threadwhichismorepronounced,themoretheShuttleBeak
pressesagainsttheStopSpring.
Itisimportanttokeeptheseadditionaltensionsaslowaspossibletominimizetheirinfluenceonthequalityof
thesewing.Lubricatetheshuttlewithkeroseneandnotoil.Kerosene’slowerviscosityreducesthefrictionmore
thanoilandthusreducestheadditionaltensions.
ELNAintroducedtheautomaticThreadReleaseon
SupermaticandTransformamachinesstartingapproximately
withSerialNo.527,626.
TheautomaticThreadReleaseallowstheupperthreadloop
topassfreelyinandoutoftheshuttlebeakandguardring
stopsatthemomentitisdrawnoutoftheshuttlebythe
threadTake‐upLeverresultingingreaterregularityinthe
threadtensionsandhighqualitystitches.
TheLoopSpringwasaddedtotheautomaticThreadRelease
startingapproximatelywithSerialNo.627,000.
TheLoopSpringensuresthattheloopofupperthreaddoes
notescapetooearlyandpassesintherightpositionoutof
theshuttlebeforeitisdrawnupintothematerialbythe
threadTake‐upLever,thuspreventingtheloopfromtwisting
andformingknotsintheseam.
TheThreadReleasepivotsup‐and‐downwhenthemachineis
running.ItisdrivenbytheReleaseSkidwhichridesagainst
theReleaseCamasitrotatesontheLowerShaft.
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