PROBLEM TO BE SOLVED: To facilitates the handling of spread paper in processing by dividing the spread paper including a top plate, side plates, and end planks into each part, and to preferably keep a degree of accuracy and strength at connecting corner parts of each side of the top plate by facilitating the assembly work of the spread paper easy.SOLUTION: The spread paper P1 of a lid 13 is equipped with the side plates 13B, 13B beyond longitudinal V grooves y1 on both sides in the transverse direction of the top plate 13A and the end plates 13C, 13C beyond transverse V grooves x1 on both sides in the longitudinal direction. The top plate 13A is formed by being divided into longitudinal frame pieces 13Ay, 13Ay and lateral frame pieces 13Ax, 13Ax which are continued with a constant plate width toward the inside of the plate surface from each side of the top plate 13A and a middle lid piece 13Az connected to the frame bodies. Acute angle end surfaces f which divide plate surface corner parts of the top plate 13A are formed at both ends of the longitudinal frame piece 13Ay and the transverse frame piece 13Ax. When the spread paper P1 is assembled, the frame bodies are assembled by connecting the mutual acute angle end surfaces f together while keeping the longitudinal frame piece 13Ay and the transverse frame piece 13Ax on the same plane.COPYRIGHT: (C)2008,JPO&INPIT【課題】天板、側板、妻板を含む展開紙をパーツ毎に分割することで、その加工時の取り扱いを容易にし、展開紙の組立作業を簡単にして天板各辺の連結角部における精度および強度を良好に保つ。【解決手段】蓋13の展開紙P1は、天板13Aの横方向両側に縦V溝y1を隔てて側板13B,13Bが設けられ、縦方向両側に横V溝x1を隔てて妻板13C,13Cが設けられる。天板13Aは、その各辺からその板面内向きに一定の板幅で連なる縦枠片13Ay,13Ayと、横枠片13Ax,13Axと、これらの枠体に連結される中蓋片13Azとに分割して形成される。縦枠片13Ayと横枠片13Axの両端には天板13Aの板面角部を分断する鋭角端面fが形成され、展開紙P1の組立時には、縦枠片13Ayと横枠片13Axとを同一平面上に保って互いの鋭角端面f同士を連結することにより枠体を組む。【選択図】図4
