Pfaff EXPRESSION 2014, Service Manual, Page: 68 / 112

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28. Changing the bevel gears
Note:
Always change bevel gears in pairs.
Removal:
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Remove the mains plug of the machine.
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Remove the detachable work support.
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Unscrew and remove the three fastening screws of the baseplate.
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Remove both connection plugs 3 and 4 from the circuit board.
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Unscrew and remove both fastening screws 5 on the free-arm cover.
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Bring the feed-dog lowering mechanism to the normal working position.
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Using a small screwdriver, disengage both feed regulators 6.
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Remove the free-arm cover carefully from the housing to the left and place it aside the machine.
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Remove the needle plate.
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Remove the buttonhole sensor and place it aside the machine.
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Dismantle feed-dog lowering mechanism 107 (fig. 81).
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Disconnect both pull-springs 3 and 9.
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Unscrew and remove screw 60 of the bobbin case position finger 61.
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Remove the bobbin case position finger.
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Turn the handwheel until the lobe of feed eccentric 5 is at the rear.
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Unscrew and remove screw 4 and clamping plate 21.
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Fold feed regulator 6 downwards and remove it with link 7 to left from the driving bar pin.
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Loosen the three screw 29 on the lower flat-toothed belt sprocket 94.
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Unscrew and remove screw 108 of feed eccentric 5.
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Unscrew and remove screw 57 of lifting eccentric 109.
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Move hook driving shaft 28 as far as possible to the right.
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Loosen screw 22 and remove pin 23.
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Unscrew and remove screw 10 of clamping plate 110.
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Remove the left cylindrical pin 12.
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Unscrew and remove both fastening screws 111 of the hook bearing.
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Pull feeding stroke shaft 14 slightly downwards and dismantle the complete sewing hook together with
lifting eccentric 109.
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Loosen both screw 53 of the sewing hook (fig. 82).
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Pull the small hook driving shaft with bevel gear 56 downwards to remove.