Blow molding apparatus

A molding apparatus for obtaining a molded product by firmly fitting a molten thermoplastic resin onto a molding surface of a mold under a pressure lower than or equal to 100 kg/cm.sup.2 and curing, comprising:

• a mold main body;
• a mold body on which said molding surface is defined;
• supporting means for supporting said mold body relative to said mold main body with maintaining a space on the back side of said molding surface in a heat insulative manner, said supporting means including at least a heat insulative supporting member having a thermal conductivity of 0.001 to 1 Kcal/mh .degree.C. and a longitudinal elastic modulus of 0.01 to 10 kg/cm.sup.2 ;
• heating means for heating said molding surface from the back side thereof to a temperature higher than or equal to Vicat softening temperature (T) .degree.C. of said thermoplastic resin;
• cooling means for cooling said molding surface from the back side thereof to a temperature lower than or equal to (Vicat softening temperature (T) of the thermoplastic resin -10) .degree.C.;
• wherein said heating means includes a radiation heating device arranged at a position in the space opposing to the back side of the molding surface.

A molding apparatus for obtaining a molded product by firmly fitting a molten thermoplastic resin onto a molding surface of a mold under a pressure lower than or equal to 100 kg/cm.sup.2 and curing, comprising:

• a mold main body;
• a mold body on which said molding surface is defined;
• supporting means for supporting said mold body relative to said mold main body with maintaining a space on the back side of said molding surface in a heat insulative manner, said supporting means including at least a heat insulative supporting member having a thermal conductivity of 0.001 to 1 Kcal/mh .degree.C. and a longitudinal elastic modulus of 0.01 to 10 kg/cm.sup.2 ;
• heating means for heating said molding surface from the back side thereof to a temperature higher than or equal to Vicat softening temperature (T) .degree.C. of said thermoplastic resin;
• cooling means for cooling said molding surface from the back side thereof to a temperature lower than or equal to (Vicat softening temperature (T) of the thermoplastic resin -10) .degree.C.;
• further comprising:
• first pressurized fluid supply means for supplying a pressurized fluid into said space;
• second pressurized fluid supply means for supplying a pressurized fluid depressing said thermoplastic resin onto said molding surface of the molding surface side;
• and
• pressure adjusting means for following the pressure of one of said pressurized fluids to the pressure of the other pressurized fluid.