SELF-LOCKING STRUCTURE FOR SEAT BACKREST FOLDING

摘要

A self-locking structure for seat backrest folding has a seat linking board (21) fixedly linked with a seat and pivotally linked with a transitionary board (22) via an angle adjuster. The transitionary board is pivotally linked with a backrest linking board (24) and is fixedly linked with a locking block which is provided with a locking indentation (223). The backrest linking board is pivotally linked with a locking boss (26) via a locking shaft (241), and a replacement component is set between the backrest linking board and the locking boss. A locking part (261) of the locking boss engages with the locking indentation (223) under the effectof the replacement component so as to form self-locking. The locking boss (26) is linked with an unlocking mechanism, which can force the locking boss (26) to turn around the locking shaft (241) under the effect of an external force in order to unlock the locking part (261) and the locking indentation (223). Without regard to the angle of the backrest, the backrest can be folded smoothly through operating the unlocking mechanism.