Resin cast device and resin cast method

A resin molding device comprising:

• a controller;
• a mold including a molding space in which a resin molded product is to be formed by injection molding, the mold comprising a concave mold portion and a convex mold portion;
• an air ejector to remove, by air injection, the resin molded product formed in the molding space from a molding surface of the mold;
• and
• an air supply source for supplying air to the air ejector,
• wherein the air ejector includes:
• an air passage formed inside the mold;
• an air outlet at a molding-space side of the air passage to inject air between the resin molded product formed in the molding space and the molding surface of the mold;
• a movable valve movably accommodated inside the air passage;
• a bias member configured to bias the movable valve in a closing direction so as to close the air outlet;
• an air supply path through which the air is supplied from the air supply source to the air passage;
• an air pressure detector on the air supply path and configured to detect a pressure of the air;
• and
• a pressure reducing valve on the air supply path and configured to reduce an air pressure of the air supplied from the air supply source to the air passage,
• wherein the controller is configured to:
• when the resin molded product is being removed from the molding space, control the air ejector to supply the air from the air supply source to the air passage via the air supply path at an ejection air pressure larger than a bias force of the bias member so as to move the movable valve so that the movable valve protrudes from the air outlet and thereby opens the air outlet to remove the resin molded product from the molding space;
• and
• after the resin molded product has been removed from the molding space, control the air ejector to supply the air from the air supply source to the air passage via the air supply path at a detecting air pressure which is reduced by the pressure reducing valve to be smaller than the bias force of the bias member but larger than zero, and to compare the detecting air pressure and an actual air pressure detected by the air pressure detector to determine the presence of a defect in the movable valve or an abnormality in the operation of the movable valve,
• wherein the air supply path includes a first air supply path section and a second air supply path section disposed in parallel to each other and both arranged between the air supply source and the air passage, a first on-off valve on the first air supply path section, and a second on-off valve on the second air supply path section,
• wherein the air pressure detector is on the second air supply path section, and
• wherein the controller is further configured to:
• when the resin molded product is being removed from the molding space, control the air ejector to open the first on-off valve and close the second on-off valve so as to supply the air to the air passage via the first air supply path section at the ejection air pressure larger than the bias force of the bias member, and
• after the resin molded product has been removed from the molding space, control the air ejector to close the first on-off valve and open the second on-off valve so as to supply the air to the air passage via the second air supply path section at the detecting air pressure which is reduced by the pressure reducing valve to be smaller than the bias force of the bias member.