DIFFERENTIAL FEED |
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The differential feed | has two independent | feed dogs, | one | ||||
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front | (A) and one rear (B). |
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Each | feed dog has | an | individual | feed mechanism | which | ||
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enables the feeding | of | material at | a different ratio. |
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B
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POSITIVE DIFFERENTIAL | FEED |
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WHEN SET FOR POSITIVE DIFFERENTIAL FEED, the front | |||||
feed dog (A) makes a longer stroke than the rear feed dog | |||||
(B). |
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This has the effect | of accumulating | material | under the | ||
the fabric. |
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presser foot to offset | the wavering | on |
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NEGATIVE DIFFERENTIAL | FEED |
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WHEN SET FOR NEGATIVE DIFFERENTIAL | FEED, the | |||||||
front feed dog (A) makes a shorter stroke | than the rear | feed | ||||||
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dog (B). |
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This has the effect of stretching material | under the presser | |||||||
foot to offset | the | puckering on the | fabric. |
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Illustration | * | I | Differential feed | dogs |
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| * | II: | Positive differential feed |
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| *111: | Negative differential | feed |
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