An injection molding system includes: an injection molding machine; an inspection device including a first placement unit, a second placement unit, an inspection unit, and a moving unit configured to change a relative position between the first placement unit and the inspection unit and a relative position between the second placement unit and the inspection unit; a third placement unit; a robot configured to convey the molded object; and a control device. The control device controls the injection molding machine, the robot, and the inspection device so as to mold a first molded object during a first molding period, inspect the first molded object placed on the first placement unit during a first inspection period, convey the first molded object after inspection from the first placement unit to the third placement unit during a first conveyance period, mold a second molded object during a second molding period, inspect the second molded object placed on the second placement unit during a second inspection period, convey the second molded object after inspection from the second placement unit to the third placement unit during a second conveyance period, and overlap the first inspection period and the second molding period and overlap the second inspection period and the first conveyance period.

A method for producing a foam-molded product uses a producing apparatus including a plasticizing cylinder. The plasticizing cylinder has a plasticization zone, a starvation zone, and an introducing port which is formed in the plasticizing cylinder and via which a physical foaming agent is introduced into the starvation zone. The method includes: plasticizing and melting a thermoplastic resin into a molten resin in the plasticization zone; introducing a pressurized fluid containing the physical foaming agent having a fixed pressure into the starvation zone; allowing the molten resin to be in the starved state in the starvation zone; bringing the molten resin in the starved state into contact with the pressurized fluid having the fixed pressure in the starvation zone; and molding the molten resin into the foam-molded product. At least one pressure boosting part is provided in the starvation zone.

A method for producing a foam-molded product uses a producing apparatus including a plasticizing cylinder. The plasticizing cylinder has a plasticization zone, a starvation zone, and an introducing port which is formed in the plasticizing cylinder and via which a physical foaming agent is introduced into the starvation zone. The method includes: plasticizing and melting a thermoplastic resin into a molten resin in the plasticization zone; introducing a pressurized fluid containing the physical foaming agent having a fixed pressure into the starvation zone; allowing the molten resin to be in the starved state in the starvation zone; bringing the molten resin in the starved state into contact with the pressurized fluid having the fixed pressure in the starvation zone; and molding the molten resin into the foam-molded product. At least one pressure boosting part is provided in the starvation zone.

1. A plasticizing device includes a barrel including a resin material supply port portion and a fiber supply port portion which is formed on a distal side from the resin material supply port portion; and a screw that comprises a shaft body and a flight, and is received in the barrel. The barrel is disposed with a posture in which its axial line intersects a gravitational direction. A maximum length of an opening in the barrel of the fiber supply port portion along an axial direction of the barrel is 1 time or more and 2 times or less as much as a pitch of the flight disposed in a portion of the screw which faces the opening in the barrel of the fiber supply port portion in a direction perpendicular to the axial line of the barrel.

1. A plasticizing device includes a barrel including a resin material supply port portion and a fiber supply port portion which is formed on a distal side from the resin material supply port portion; and a screw that comprises a shaft body and a flight, and is received in the barrel. The barrel is disposed with a posture in which its axial line intersects a gravitational direction. A maximum length of an opening in the barrel of the fiber supply port portion along an axial direction of the barrel is 1 time or more and 2 times or less as much as a pitch of the flight disposed in a portion of the screw which faces the opening in the barrel of the fiber supply port portion in a direction perpendicular to the axial line of the barrel.

A method for increasing the injection speed of a melted plastic injection device for injecting said melted plastic into a molding cavity (51), said injection device comprising a first cylinder (1) provided with a tubular casing (2) defining a first inner diameter d.sub.1, and a first piston (3) slidable inside said tubular casing (2), adapted to be loaded with melted plastic and to inject said melted plastic toward the molding cavity (51); a second cylinder (21) constrained to the first cylinder (1) and provided with a second piston (23) which rod (24) is connected to the first piston (3) and is adapted to actuate said first cylinder (1) during an injection operation; the method comprising the steps of: —releasing second cylinder (21) and first cylinder (1) by extracting the first piston (3) from the tubular casing (2); —coaxially inserting a tubular body (12), defining a second inner diameter d.sub.3 which is smaller than the first inner diameter d.sub.1, into the tubular casing (2); —disconnecting the first piston (3) from the rod (24); —connecting a third piston (13) to the rod (24), said third piston (13) being sized to slide inside said tubular body (12); —constraining second cylinder (21) and first cylinder (1) by inserting the third piston (13) into the tubular casing (2).

A method for increasing the injection speed of a melted plastic injection device for injecting said melted plastic into a molding cavity (51), said injection device comprising a first cylinder (1) provided with a tubular casing (2) defining a first inner diameter d.sub.1, and a first piston (3) slidable inside said tubular casing (2), adapted to be loaded with melted plastic and to inject said melted plastic toward the molding cavity (51); a second cylinder (21) constrained to the first cylinder (1) and provided with a second piston (23) which rod (24) is connected to the first piston (3) and is adapted to actuate said first cylinder (1) during an injection operation; the method comprising the steps of: —releasing second cylinder (21) and first cylinder (1) by extracting the first piston (3) from the tubular casing (2); —coaxially inserting a tubular body (12), defining a second inner diameter d.sub.3 which is smaller than the first inner diameter d.sub.1, into the tubular casing (2); —disconnecting the first piston (3) from the rod (24); —connecting a third piston (13) to the rod (24), said third piston (13) being sized to slide inside said tubular body (12); —constraining second cylinder (21) and first cylinder (1) by inserting the third piston (13) into the tubular casing (2).

A cylinder for a molding machine comprising a HIP-sintered lining layer on an inner surface of a cylindrical steel body, the lining layer comprising 38-70% by volume of tungsten carbide particles having a median diameter d.sub.50 of 1-7 μm and a matrix composed of an Ni-based alloy, and the maximum length of the matrix in an arbitrary cross section being 12 μm or less.

Provided is a resin molded product having excellent scratch resistance. The resin molded product of the present invention is a resin molded product including a methacrylic-based resin composition, in which the methacrylic-based resin composition contains a (meth)acrylic-based polymer (A) and a fatty acid compound (B), and an absorbance ratio P1/P2 of a peak absorbance P1 in a wave number range of 1630 to 1650 cm.sup.−1 to a peak absorbance P2 in a wave number range of 1710 to 1730 cm.sup.−1 on a surface of the resin molded product, measured by a single reflection ATR surface reflection method with an infrared spectrophotometer, is 0.0040 or more.

A stepped flight is formed on a screw of an injection molding machine. The stepped flight is a flight in which a step-shaped step portion is formed on a top portion thereof. The top portion of the flight includes a large diameter portion on an upstream side and a land portion on a downstream side. When a gap ratio m of a gap H.sub.1 between the land portion and a bore of the heating cylinder to a gap H.sub.2 between the large diameter portion and the bore is defined as H.sub.1/H.sub.2, the gap ratio m is selected to be 2.3≤m≤6.4.