RIVETING METHOD AND FASTENED OBJECT

WIPO Patent Application WO/2024/004679

A1

A metal rivet (1a) set in a position separated from a surface (50b) of a second material (50) to be fastened is moved toward a position of a prepared hole (41), and the rivet (1a) is driven in the order of the second material (50) to be fastened and a first material (40) to be fastened to arrive inside the prepared hole (41). The prepared hole (41) includes a hole portion (43) having an inner wall surface that is a tapered substantially cone shape or substantially truncated cone shape, the rivet (1a) has a tapered first shaft part (3), the depth of the hole portion (43) is deeper than the length of the first shaft part (3), the first shaft part (3) has a distal portion (3a1) which shrinks in diameter toward the distal side, the outer peripheral surface of the first shaft part (3) is engraved with a spiral groove (3b) from the proximal side to the distal side, and the relationship between a depth (H) of an opening (42) and a thickness (T) of the driven position of the rivet (1a) of the second material (50) to be fastened is 0.25×T