Patent ID: 7597375
Filing Date: 2009-10-06
Classification: B60N

Abstract:
1. A double folding mechanism of a seat of a vehicle, which mechanism can fold a seat cushion from a space on a floor and fold a seat back into the space, thereby changing the seat from a use condition to a retracted condition, comprising: a first connecting mechanism connecting the seat cushion and the floor, the first connecting mechanism comprises a first rotational mechanism that supports the seat cushion on the floor so as to be rotatable in a folding and unfolding direction, a first biasing device that biases the seat cushion supported by the first rotational mechanism in the folding direction, and a first retaining mechanism that retains the seat cushion biased by the first biasing device in a use position, and a second connecting mechanism connecting the seat back and the floor, the second connecting mechanism comprises a second rotational mechanism that supports the seat back on the floor so as to be rotatable in a folding and unfolding direction, a second biasing device that biases the seat back supported by the second rotational mechanism in the folding direction, a second retaining mechanism that retains the seat back biased by the second biasing device in a use position, and a biasing force control device capable of controlling a rotational speed of the seat back rotating in the folding direction, wherein the first and second retaining mechanisms are arranged and constructed to be released in one operation, wherein the biasing force control device of the second connecting mechanism is arranged and constructed to control the rotational speed of the seat back such that the seat back can enter inside a rotational trajectory of a rear end portion of the seat cushion after the seat cushion comes out of a rotational trajectory of an upper end portion of the seat back, wherein the first rotational mechanism comprises a rotating member that is rotatably connected to the floor via a first rotational shaft and is rotatably connected to the seat cushion via a second rotational shaft that is positioned parallel to the first rotational shaft, and a detent device that is positioned between the rotational member and the seat cushion so as to control the rotation of the seat cushion about the second rotational shaft, wherein the rotating member is arranged and constructed to be capable of rotating the rear end portion of the seat cushion downwardly about the second rotational shaft until the detent device functions when the rotating member rotates in the folding direction, so that the rear end portion of the seat cushion moves along the rotational trajectory that does not interfere with the seat back, the rotational trajectory being different from a hypothetical rotational trajectory of the rear end portion expected in case that the rear end portion is not rotated downwardly, and wherein the seat cushion is positioned such that the hypothetical rotational trajectory will interfere with the seat back.