| 摘要 |
PROBLEM TO BE SOLVED: To reduce seat vibration effectively by a headrest attached to a seat back and improve the impact absorption power in the fore-and-aft section.SOLUTION: Leg parts 11a of a pair of right and left frame members 11 of a headrest 3 are inserted freely rotatably into sockets 7 of a seat back 5 and supported, and upper end parts 11b of the right and left frame members 11 are connected elastically to each other through a connection body 12 so as to have elasticity in the fore-and-aft and right-and left directions. The connection body 12 is composed of an elastic member 13 which connects together upper end parts 11b of the right and left frame members 11 and a pipe-like case 14 which houses and holds the elastic member 13. The configuration makes the resonance frequency of the head rest 3 nearly equal to the resonance frequency of the seat back 5, leading to reduction of uncomfortable seat vibration and improvement of the crew protection performance by increasing the absorption stroke against fore-and-aft direction impact. |
