Patent ID: 7971939
Filing Date: 2011-07-05
Classification: B60N

Abstract:
1. A seat structure comprising: a sitting portion frame that is substantially flat; a cushion material including a first sheet material, of which only (1) a front edge side is fixed directly to a front edge side of the sitting portion frame and (2) a back edge side is directly connected to a back edge side of the sitting portion frame via a resilient member extending along the back edge side substantially parallel to the front edge side; and a second sheet material which is easier to stretch in a left-right direction rather than in a front-rear direction, which is tensioned onto left and right sides of the sitting portion frame at an upper side of the first sheet material, and which presses a region of the first sheet material corresponding to a buttock portion of a sitter such that the resilient member is deformed, wherein the resilient member deforms such that the back edge side of the first sheet material moves forward or downward when a downward load acts on the cushion material, and in a process where the second sheet material is displaced upward, the extension of the second sheet material in the left-right direction becomes smaller such that the seat structure has an attenuation ratio that is larger when the sitter displaces upward than an attenuation ratio when the sitter displaces downward.