Hollow structure plate, manufacturing method thereof, manufacturing device thereof, and sound absorbing structure plate

Abstract

Introduction guidesare provided above and below a sheet-introduction opening portion of a pressure-reduced chamber, and heating meansis provided between the introduction guides. Each resin sheetis attracted and attached respectively to the circumferential surface of a corresponding emboss rollerby reducing pressure. Pinsof the emboss rollerare truncated cone-shaped. The ratio of the total area of the lower bases of the pinsto the area of the circumferential surface of the emboss roller is 0.5 or more. The rising angle θ of the pin side face, in the vertical plane including the central axis of the pins, is in the range from 50 degrees to 70 degrees. Furthermore, a multilayered hollow structure plateis formed by attaching non-air-permeable sheetsonto both the front and back of a core member obtained by fusing together hollow protrusionsin two thermoplastic resin sheets. A sound absorbing materialis provided on at least one of the front and back side thereof, and small holesopened in the multilayered hollow structure plate are formed in liner portionsand the non-air permeable sheetonly in the positions that matches the liner portions