Brother RH-981A, Руководство по обслуживанию

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3. ASSEMBLY
RH-981A
23
3-4. Lower shaft mechanism
1. Fit the two ball bearings into the holes in the bed, insert the lower shaft (1) from the left.
2. Put the timing belt (2), the lower shaft tension pulley assembly (3), the lower shaft cam (4), and the set collar (5),
in this order, on the lower shaft (1), and tighten the two set screws (6) of the set collar (5) so that there is no play
between the parts on the lower shaft (1).
3. Lightly press the lower shaft tension pulley assembly (3) and the lower shaft cam (4) against the left ball bearing,
and tighten the two set screws (7) of the lower shaft cam (4).
* The screw flat should align with the set screw which comes first when the lower shaft is rotated in the rotation
direction.
4. When the screw flat of the upper shaft is at the top, and the two set screws (8) of the lower shaft tension pulley
assembly (3) are as shown in figure 1, loop the timing belt over the lower shaft tension pulley assembly (3).
3-4-1. Adjusting the timing belt
Use a screwdriver or similar tool to press the notch of
the tension pulley arm assembly (1) with a force of 39.2
N, and attach the tension pulley assembly.
3722Q
<Figure 1>
3723Q
3721Q