US 7,971,939 B2 · Seat structure

Abstract

A seat structure which can ameliorate fatigue of a sitting person in accordance with a long period of sitting is provided. In a vehicle seat 10, a back edge side of a lower layer sheet 50 of a cushion material 20, of which a front edge side is fixed to a front edge side of a sitting portion frame 14, is resiliently connected to a back edge side of the sitting portion frame 14 via a movable frame 34 and a torsion bar 46, which is a resilient member. The cushion material 20 has a spring zero characteristic in which a spring constant of a portion that supports a protrusion portion of the sitting person is smaller than a spring constant of other portions. This vehicle seat 10 makes smaller the energy of vibrations which are transmitted to a spinal column portion of the sitting person through the sitting portion frame 14, and peripheral portions thereof convert vibrations corresponding to fluctuations in the body and transmit these through the sitting portion frame 14. α waves of 10 Hz to 12 Hz, which occur in a relaxed waking state, are caused in the brain of the sitting person. Vibrations in a resonance frequency region are attenuated in amplitude and transmitted to the sitting person.

Claims10

Dependent claims

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.

3 more elements

Dependencies are inferred from the claim text.

Seat structure

Life of this patent

Seat structure

Life of this patent

Abstract

Claims10