Singer CONFIDENCE 7467 - Page 37

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ZIGZAG BIGHT CONTROL UNIT
A. Position of pulse motor gear at origin point
Added: January, 2006
Rotational ratio of Motor pinion gear (A) vs zigzag cam gear (B) is 1:1. Rotation of motor gear (A) 1/2 step per
1 pulse and 3.75 degrees (7.5 divided by 2) resulting in the gear (B) rotated at 3.75 degrees.
There are 48-step exciting positions (segments) with 7.5 degree rotation per 1 pulse on the pulse motor.
Therefore, 3.5 degree rotation per 1 pulse coincides with exciting position and center of non-exciting positions
alternatively.
Zigzag bight is 0.25 mm for rotation of motor gear (A) of 3.75 degrees per 1 pulse.