Patent ID: 8801417
Filing Date: 2014-08-12
Classification: B29C,B29K

Abstract:
1. A sheet forming die comprising: a die main body; a connection block; a first resin extruder configured to supply a first molten resin; a second resin extruder configured to supply a second molten resin; a lip gap formed in the die main body and configured to discharge the first molten resin and the second molten resin to form a sheet-shaped resin-made product; a first passage provided to flow the supplied first molten resin up to an upstream end of a lip part located upstream of the lip gap, the first passage extending from the connection block through the die main body; a second passage provided to flow the supplied second molten resin up to the lip part, the second passage extending from the connection block through the die main body, the second passage branching out in the connection block into two passageways in a midstream portion thereof, downstream ends of these passageways being connected to portions in an upstream end of the lip part, respectively; two temperature controllers, each controller configured to locally control a temperature of a midstream portion of a corresponding one of the two passageways in order to control flow rates of the second molten resin in the two passageways; wherein the die main body is configured so that one of the second molten resins flows together with the first molten resin at one of a pair of edge ends of the first molten resin in a width direction of the first molten resin and another of the second molten resins flows together with the first molten resin at another of the pair of edge ends of the first molten resin in the width direction of the first molten resin to form the sheet-shaped resin-made product; and two tubular restrictor constituting members provided in midstream portions of each of the two passageways in a connection portion of the die main body and the connection block and formed as bodies separated from the sheet forming die and separated from portions of each of the two passageways that are upstream of the temperature controllers, wherein each of the restrictor constituting members is formed with a through-hole configured to receive a flow of the second molten resin and configured so as to be mounted integrally with the die main body and the connection block when the connection block is mounted on the die main body; each of the through-holes is configured by two larger diameter parts and a smaller diameter part which is sandwiched between the two larger diameter parts; each of the temperature controllers is ring shaped and is located around a periphery of the smaller diameter part of the through-hole of the corresponding restrictor constituting member; each of the temperature controllers is configured to control a flow rate of the second molten resin by changing a temperature of the corresponding restrictor constituting member, thereby changing a temperature of the second molten resin in the corresponding restrictor constituting member so that a viscosity of the second molten resin is controlled; and each of the two passageways between each of the restrictor constituting members and each of the downstream ends of the passageways connected to portions in the upstream end of the lip part is located in the die main body.