US Patent 7425039 Body-supporting device

A body-supporting device includes a tray, a net and a frame. The tray includes a margin and a groove in the margin. The groove gets narrower downwardly. The net includes a margin. The frame includes a first rib for inserting the margin of the net into the groove of the tray and a second rib for pressing the margin of the net against the margin of the tray. The first rib gets narrower downwardly. Fasteners are driven into the first rib of the frame through the margin of the tray. The sandwiching of the margin of the net between the first rib of the frame and the margin of the tray gets firmer as the fasteners get tighter in the first rib of the frame.