Singer Confidence 7463 Service Manual page 37

ZIGZAG BIGHT CONTROL UNIT
A. Position of pulse motor gear at origin point
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.
Added: January, 2006
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