Splicing mechanism for seat unit and seat unit

A splicing mechanism for a seat unit, comprising:

• a fixed frame, comprising a first fixed frame and a second fixed frame, the first fixed frame and the second fixed frame being provided adjacent to each other;
• a first splicing assembly, comprising a first splicing member and a second splicing member, the first splicing member and the second splicing member being provided on the first fixed frame;
• a second splicing assembly, comprising a first splicing groove and a second splicing groove provided on the second fixed frame, wherein an opening direction of the first splicing groove and an opening direction of the second splicing groove are arranged in an intersecting manner, and rotation of the second fixed frame drives the first splicing member to be cooperatively connected with the first splicing groove and drives the second splicing member to be cooperatively connected with the second splicing groove after the first splicing member is aligned with the first splicing groove.