Adjustment Procedures; The Feed Eccentric; The Upper Driving Belt Sprocket - Pfaff 260 Service Manual

ADJUSTMENT PROCEDURES
The following instructions apply to bot'
h th~
P*a#
260
flat-bed and the Pfaff
360 free-arm sewing machine. Wherever variations in design necessitate differ-
ent adjustment procedures, each procedure will be discussed separately. To
check the settings of a machine or to reset it after it has been stripped and
reassembled, follow the procedures outlined below:
-2mm f.08'' )
Fig. 76 Fig.
n
The Feed Eccentric
Make sure the timing marks on the feed eccentric and on the arm shaft are in
line. Push the eccentric to the right until there is a clearance of about
5 /6.·,
or
2.0 mm, between it and the rear bearing bushing on the arm shaft (Fig. 76).
Tighten the eccentric set screws securely.
The Upper Driving Belt Sprocket
The correct position of the driving belt sprocket on the arm shaft is of eminent
importance for the proper balancing of this shaft. Before you adjust the posi-
tion of the sprocket, toke core that the feed eccentric has been set very accu-
rately, as instructed above. To position the sprocket on the arm shaft correctly,
push it toward the feed eccentric and make sure that its position pin (which
should point toward the balance wheel) enters the borehole in the eccentric
(Fig. 77). Then tighten both set screws in the driving belt sprocket securely.
On all machines fitted with a clip belt, the sprocket position pin should engage
the small recess S in the collar of the feed eccentric. This recess should be
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