Canon iR4570 Series Service Manual page 672

Chapter 12
Check to be sure that the joint pin is fully fitted as shown in the figure.
8) Using the self-tapping screw [1] you removed in step A-5), fix the joint plate [2] in place.
Check to be sure that the protrusion [3] of the joint plate is fully in the mounting hole.
10) Mount the right cover (rear) using 5 screws.
12-28
F-12-48
F-12-49
F-12-50