Canon imageRUNNER 6570 Reference Manual page 541

3
Pull the stapler unit of the saddle stitcher unit towards you,
and then push it up.
4
Pull out the staple cartridge containing the jammed staples,
holding it by its left and right sides.
5
On the staple case, push down Part A, and push up Part B.
B
Stapler Unit of the
Saddle Stitcher Unit
A
Clearing Staple Jams
9
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