Container, and thermal forming device and thermal forming method therefor

Abstract

The present invention provides a bottomed cylindrical container, comprising a body wall, a bottom wall, and a ring-shaped foot downwardly extending from the bottom wall, said container being produced by thermo-molding a resin sheet, characterized in that said foot is formed by folding an inner wall by compressed fluid to be fusion-bonded with an outer wall, so as to form the foot comprising the inner wall and the outer wall. The present invention also provides a bottomed cylindrical container, comprising a body wall having a grounding edge at a lower end thereof, and a bottom wall, said container being produced by thermo-molding a resin sheet, characterized in that said bottom wall connects with an upper edge of an inner wall produced by folding back the body wall along the grounding edge and by fusion-bonding it to an inner periphery of the body wall. In addition, the present invention provides the methods for thermo-molding these containers and their apparatuses.

1 . A bottomed cylindrical container, comprising a body wall, a bottom wall, and a ring-shaped foot downwardly extending from the bottom wall, 
 said container being produced by thermo-molding a resin sheet, characterized in that    said foot is formed by folding an inner wall by compressed fluid to be fusion-bonded with an outer wall, so as to form the foot comprising the inner wall and the outer wall.    
     
     
         2 . The bottomed cylindrical container according to  claim 1 , wherein 
 said bottom wall comprises a central section and a peripheral section, and    the peripheral portion is made thin.    
     
     
         3 . A bottomed cylindrical container, comprising a body wall having a grounding edge at a lower end thereof, and a bottom wall, 
 said container being produced by thermo-molding a resin sheet, characterized in that    said bottom wall connects with an upper edge of an inner wall produced by folding back the body wall along the grounding edge and by fusion-bonding it to an inner periphery of the body wall.    
     
     
         4 . An apparatus for thermo-molding a resin sheet to a bottomed cylindrical container, comprising an upper mold having a plug, and a lower mold having a female mold and a bottom bush, wherein 
 said female mold has mold surfaces for forming a body wall of the container, and    said bottom bush has compressed air blow-in holes.    
     
     
         5 . An apparatus for thermo-molding a resin sheet to a bottomed cylindrical container with a ring-shaped foot, comprising an upper mold having a plug, and a lower mold having a female mold and a bottom bush, wherein 
 said female mold is provided with suction holes,    said female mold has a mold surface for forming a body wall of the container, a mold surface for forming a bottom peripheral wall of the container, and a mold surface for forming an outer wall of the foot, and    said bottom bush has compressed fluid blow-in holes.    
     
     
         6 . The apparatus according to  claim 4 , wherein 
 said lower mold comprises a mold base, the bottom bush in the mold base, and the female mold on the mold base,    a gap is formed between a lower surface of the female mold and the mold base, and    an annular suction groove is formed between a lower surface of the female mold and the mold base, and communicates with the gap.    
     
     
         7 . A method for thermo-molding a footed and bottomed cylindrical container, comprising 
 heating a thermoplastic resin sheet,    pressing the heated sheet by a plug of an upper mold with vacuum-sucking, to contact the sheet with mold surfaces of a female mold of a lower mold, so as to form a body wall and an outer wall of a foot of the container, and    blowing compressed fluid through blow-in holes of a bottom bush of the lower mold into the female mold with vacuum-sucking, to contact the sheet on a top surface of the bottom bush with a bottom surface of the plug, so as to form a bottom wall and an inner wall of the foot, said inner wall being fusion-bonded with the outer wall.    
     
     
         8 . A method for thermo-molding a bottomed cylindrical container, comprising: 
 heating a thermoplastic resin sheet,    pressing the heated sheet by a plug of an upper mold with vacuum-sucking, to contact the sheet with mold surfaces of a femal mold of a lower mold, so as to form a body wall of the container, and    blowing compressed fluid through blow-in holes of a bottom bush of the lower mold into the female mold with vacuum-sucking, to contact the sheet on a top surface of the bottom bush with a bottom surface of the plug, so as to form a bottom wall and an inner wall being fusion-bonded with the body wall.    
     
     
         9 . The apparatus according to  claim 5 , wherein 
 said lower mold comprises a mold base, the bottom bush in the mold base, and the female mold on the mold base,    a gap is formed between a lower surface of the female mold and the mold base, and    an annular suction groove is formed between a lower surface of the female mold and the mold base, and communicates with the gap.