Brother S-7200C User Manual

Page of 172
 
 
S-7200C
 
11. REPLACING PARTS 
134
 
< Timing belt installation check > 
1. Check that the needle and rotary hook timing is correct. 
(Refer to “10-12. Adjusting the needle and rotary hook 
timing”.) 
*  If they are correct, continue from step 5, otherwise 
continue from step 2. 
 
2. Check that the needle and feed mechanism timing is 
correct. 
Turn the machine pulley (5) forward to lower the feed dog 
(16) from its highest position until it is aligned with the top 
of the needle plate (17), and check that the tip of the 
needle is at the following position at this time. 
The top of the feed dog (16) and the top of 
the needle plate (17) should be aligned, and 
the point of the needle should be 
approximately 1 mm below the needle plate 
(17). 
The top of the feed dog (16) and the top of 
the needle plate (17) should be aligned, and 
there should be a clearance of approximately 
3 mm between the point of the needle and 
the needle plate (17). 
 
*  If it is not in the correct position, carry out the following 
steps. 
1) Tilt back the machine head, and then loosen the two set 
screws (19). 
2) Turn timing pulley D (6) forward to lower the feed dog 
(16) until it is at the same height as the needle plate (17). 
3) While holding the vertical cam (20) with one hand so that 
it will not move, turn the machine pulley (5) forward to 
lower the needle to the correct position. 
4) Tighten the two set screws (19). 
 
 
3. Adjust the needle and rotary hook timing so that it is 
correct. 
(Refer to “10-12. Adjusting the needle and rotary hook 
timing”.) 
4. Check that the thread trimming timing is correct. If it is not 
correct, adjust it by following the adjustment procedure. 
(Refer to “10-13. Adjusting the thread trimming timing”.) 
5. Set the sewing machine to needle up stopping, and then 
operate the sewing machine and let it stop. Check that the 
reference line (d) on the machine pulley (5) is within the 
range of the mark (e) on the motor cover (3) at this time. 
(Refer to previous page)   
If the reference line (d) is not aligned within the mark (e), 
loosen the three screws (9), adjust the position of the 
machine pulley (5) so that the reference line (d) is aligned 
within the mark (e), and then tighten the three screws (9). 
6. If adjustment of the needle up stop position is necessary, 
adjust according to the procedure in “10-15. Adjusting the 
needle up stop position”. 
 
 
 
 
 
 
 
 
 
 
 
<-[][]S・[][]3> <-[][]5> 
Approx. 1mm 
Approx. 3mm 
4362M 
4363M 
4360M 
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