Patent ID: 6761307
Filing Date: 2004-07-13
Classification: B65D,Y02W,Y10S

Abstract:
In a folding box for packing made of high density foam polypropylene resin with an auto bottom structure including a first box forming body (P1) and a second box forming body (P2), each of the box forming bodies (P1) (P2) respectively including:a main face wall (2) having a connecting piece (1) extending from a first lateral side of the main face wall (2); a sub face wall (3) extending from a second lateral side of the main face wall (2); a first bottom forming board (4a) (4c) extending from a lower edge of the main face wall (2); a second bottom forming board (4b) (4d) extending from a lower edge of the sub face wall (3); a first cover forming board (5a) (5c) extending from an upper edge of the main face wall (2); and a second cover forming board (5b) (5d) extending from an upper edge of the sub face wall (3), wherein the second bottom forming board (4b) (4d) extending from the sub face wall (3) has a side edge adjacent to the first bottom forming board (4a) (4c) extending from the main face wall (2), the side edge being an inclined edge (6) having a 45 degree angle in respect with a border line between the sub face wall (3) and the second bottom forming board (4b) (4d), wherein the first and second box forming bodies (P1) (P2) are mutually connected by heat and pressure-fusion between a back surface of the sub face wall (3) of the first box forming body (P1) and a front surface of the connecting piece (1) of the second box forming body (P2), between a back surface of the sub face wall (3) of the second box forming body (P2) and a front surface of the connecting piece (1) of the first box forming body (P1), between a front surface of the first bottom forming board (4a) of the first box forming body (P1) and a back surface of a first folding connecting piece (9a) of the first box forming body (P1), and between a front surface of the first bottom forming board (4c) of the second box forming body (P2) and a back surface of a second folding connecting piece (9b) of the second box forming body (P2); the improvement comprising: lines for bending into the shape of a mountain (7c), between the main face wall (2) of the first box forming body (P1) and the first cover forming board (5a) of the first box forming body (P1), between the sub face wall (3) of the first box forming body (P1) and the second cover forming board (5b) of the first box forming body (P1), between the main face wall (2) of the second box forming body (P2) and the first cover forming board (5c) of the second box forming body (P2), and between the sub face wall (3) of the second box forming body (P2) and the second cover forming board (5d) of the second box forming body (P2), including side grooves (74) on both sides of a middle groove (72) through partitions (73), and said side grooves (74) and said middle groove (72) are disposed on an exterior surface of the folding box; lines for bending into the shape of a mountain (7a), between the main face wall (2) and the sub face wall (3) of each of the first and second box forming bodies (P1) (P2) including two side grooves (74) parallel to a border line and a wide ridge (71a) between the two side grooves (74), a width of the wide ridge (71a) being about twice a thickness of the main face wall (2), and said side grooves (74) and said wide ridge (71a) are disposed on an exterior surface of the folding box; and lines for bending into the shape of a mountain (7b), between the connecting piece (1) of the first box forming body (P1) and the main face wall (2) of the first box forming body (P1), between the connecting piece (1) of the second box forming body (P2) and the main face wall (2) of the second box forming body (P2), between the main face wall (2) of the first box forming body (P1) and the first bottom forming board (4a) of the first box forming body (P1), between the main face wall (2) of the second box forming body (P2) and the first bottom forming board (4c) of the second box forming body (P2), between the sub face wall (3) of the first box forming body (P1) and the second bottom forming board (4b) of the first box forming body (P1), and between the sub face wall (3) of the second box forming body (P2) and the second bottom forming board (4d) of the second box forming body (P2), including two side grooves (74) parallel to a border line and a narrow ridge (71b) between the two side grooves (74), and said side grooves (74) and said narrow ridge (71b) are disposed on an exterior surface of the folding box, wherein the inclined edge (6) includes the first folding connecting piece (9a) and the second folding connecting piece (9b) having a linear region bendable into the shape of a V (8) for reducing an effect of elasticity of the high density foam polypropylene resin occurring in folding, wherein a concave for fusion (10) having the high density foam polypropylene resin at a reduced thickness in the shape of an outline of the folding connecting piece (9a) (9b) is formed on a front surface of the first bottom forming board (4a) (4c), the front surface of the first bottom forming board (4a) (4c) overlapping the back surface of the folding connecting piece (9a) (9b) in assembling, and wherein the back surface of the folding connecting piece (9a) (9b) is fused on a surface of the concave for fusion (10) in assembling.