Abstract: A seat cushion extends across left and right areas that are located beneath the locations of the left and right ischial tuberosities of a seated person. A support structure beneath the cushion transmits a weight load from the cushion to the seat frame. The support structure has portions that surround the left and right ischial areas to provide the cushion with underlying, load bearing support at the peripheral boundaries of the ischial areas, and is free of load bearing portions located within or beneath the ischial areas.

Abstract: A lumbar support apparatus includes a guide rail on a seat frame, and a bendable occupant support structure mounted for sliding movement on the guide rail. The bendable structure, which is preferably configured as a grid, includes a spring that imparts increasingly bowed contours to the grid upon increasingly arched deflection of the spring relative to the seat frame and the guide rail. The apparatus further includes an actuator, a cable, and a fastener. A first section of the cable extends from the actuator into engagement with the grid so as to apply a bending force to the grid under the influence of the actuator. A second section of the cable extends from the first section to an end portion of the cable that is anchored to the seat frame.

Abstract: A seat cushion extends across left and right areas that are located beneath the locations of the left and right ischial tuberosities of a seated person. A support structure beneath the cushion transmits a weight load from the cushion to the seat frame. The support structure has portions that surround the left and right ischial areas to provide the cushion with underlying, load bearing support at the peripheral boundaries of the ischial areas, and is free of load bearing portions located within or beneath the ischial areas.