Patent ID: 7488040
Filing Date: 2009-02-10
Classification: A47C

Abstract:
1. An adjustment mechanism for a seat part swingably connected to a back rest part and arranged on a support frame for travel in a longitudinal direction in synchronism with an adjustment of the back rest part from a normal position to several predetermined reclined positions, said adjustment mechanism comprising: a lever assembly including a first pair of levers having first and second ends, with the first ends pivotally connected to the seat part, and a second pair of levers which intersect one another and have first and second ends, with the first ends rotatably connected to the support frame and the second ends pivotally connected to the second ends of the first air of levers; and a spring assembly for progressively applying a spring force upon the the first ends of the second pair of levers such that a relative change in angular disposition between the levers of the first and second pairs of levers applies a substantially constant force upon the seat part in every position of the seat part, whereby a travel distance of the seat part is greater than a spring travel of the spring assembly.