Letter Fold-in / Letter Fold-out / Z-fold

[1] The leading edge of the paper passes the registration roller.

[2] The leading edge of the paper passes the 1st fold roller (F/R).

[3] When the paper is fed to the fold-assessment position, the 1st fold roller (F/R) reverses, forming an arch in the paper.

[4] When this arched part passes through the nips of the folding rollers 1 and 2, the first fold is performed.

[5] After the paper passes the folding roller, the 2nd fold roller pulls in the paper and feeds it to the 2nd fold position.

[6] At the fold position, the 2nd fold roller (F/R) rotates in reverse to form an arch in the paper.

[7] The 2nd fold is formed when this arched part is fed through the nips of the folding rollers 2 and 3. Depending on the difference in the fold positions, Letter Fold-In, Letter Fold-Out, or Z-Fold is performed.

The following diagrams show a Letter Fold-In example.