Frame structure for a seatback of a seat

摘要

A seatback frame structure (F) for a seatback (2) of a seat (S) comprises a generally rectangular seatback frame (4) and a lower or primary wire frame (9) which has base frame sections (9a) extending from opposite vertical side frame sections (4a) of the rectangular seatback frame (4) at a height of lumbar vertebras, respectively, an upward extending support frame section (91) which extends upward from the base frame sections (9a) and comprises opposite vertical side frame sections (91b) extending from the base sections (4a), respectively, and a horizontal frame section (91a) extending between the opposite vertical side frame sections (91b) at a height of shoulder blades, and an upper or subsidiary wire frame (8) extending between the opposite vertical side frame sections (4a) behind the upward extending support frame section (91). The upward extending support frame section (91) at its upper part is bent backward so as to extend along the backbone of a person sitting on the seat (S).