Provided is a screw that is for use in an injection molding machine and that makes it possible to benefit from the kneading effect of a multi-start screw while minimizing the received friction resistance. The screw for an injection molding machine is provided with a first stage 20 on the upstream side and a second stage 30 on the downstream side. The screw for an injection molding machine is characterized in that: the first stage 20 is provided with a compression section 22 comprising a main scraper 25 and an auxiliary scraper 26 having a smaller outer diameter than the main scraper 25; and the second stage 30 is provided with a multi-start screw section 31, said multi-start screw section being provided on the upstream side and comprising a plurality of scrapers, and a fin kneading section 32 provided downstream from the multi-start screw section.

Provided is a screw that is for use in an injection molding machine and that makes it possible to benefit from the kneading effect of a multi-start screw while minimizing the received friction resistance. The screw for an injection molding machine is provided with a first stage 20 on the upstream side and a second stage 30 on the downstream side. The screw for an injection molding machine is characterized in that: the first stage 20 is provided with a compression section 22 comprising a main scraper 25 and an auxiliary scraper 26 having a smaller outer diameter than the main scraper 25; and the second stage 30 is provided with a multi-start screw section 31, said multi-start screw section being provided on the upstream side and comprising a plurality of scrapers, and a fin kneading section 32 provided downstream from the multi-start screw section.

An injection molding machine is equipped with a screw having a spline shaft formed with a spline on an outer circumferential surface, a bush having a spline hole formed with a spline on an inner circumferential surface, a linear motion motor for moving the bush in an axial direction of the screw, a rotational motion motor for rotating the bush about an axis of the screw, and a motor control unit which, in the case of fitting the spline shaft in the spline hole, controls the linear motion motor to advance the bush in a direction approaching the screw in a state that the bush and the screw are separated, and which controls the rotational motion motor to rotate the bush when the acquired output torque becomes equal to or larger than a first predetermined torque.

An injection molding machine is equipped with a screw having a spline shaft formed with a spline on an outer circumferential surface, a bush having a spline hole formed with a spline on an inner circumferential surface, a linear motion motor for moving the bush in an axial direction of the screw, a rotational motion motor for rotating the bush about an axis of the screw, and a motor control unit which, in the case of fitting the spline shaft in the spline hole, controls the linear motion motor to advance the bush in a direction approaching the screw in a state that the bush and the screw are separated, and which controls the rotational motion motor to rotate the bush when the acquired output torque becomes equal to or larger than a first predetermined torque.

To provide an ejector mechanism of an injection molding machine that improves handling performance of a sound-proof cover while ensuring excellent sound-proof performance. An ejector mechanism of an injection molding machine comprises: a plurality of ball screws that rotates clockwise and counterclockwise about an axis to make an ejector plate and an ejector pin advance and retreat together; a plurality of driven pulleys and each connected to a corresponding one of the ball screws; a driving pulley that rotates clockwise and counterclockwise in response to the driving of a driving motor; an endless transmission belt wound on the driving pulley and the driven pulleys; an idler pulley on which the transmission belt is wound in such a manner as to define a small area of a region surrounded by the endless transmission belt wound on the driving pulley and the driven pulleys; and a sound-proof cover provided to cover the driving pulley, the driven pulleys, the idler pulley, and the transmission belt.

To provide an ejector mechanism of an injection molding machine that improves handling performance of a sound-proof cover while ensuring excellent sound-proof performance. An ejector mechanism of an injection molding machine comprises: a plurality of ball screws that rotates clockwise and counterclockwise about an axis to make an ejector plate and an ejector pin advance and retreat together; a plurality of driven pulleys and each connected to a corresponding one of the ball screws; a driving pulley that rotates clockwise and counterclockwise in response to the driving of a driving motor; an endless transmission belt wound on the driving pulley and the driven pulleys; an idler pulley on which the transmission belt is wound in such a manner as to define a small area of a region surrounded by the endless transmission belt wound on the driving pulley and the driven pulleys; and a sound-proof cover provided to cover the driving pulley, the driven pulleys, the idler pulley, and the transmission belt.

The present invention discloses a biaxial or tri-axial eccentric rotor volume pulsed deformation plasticizing method and device. The method is characterized in that: the conveying volume of materials formed between two or three engaged eccentric rotors, which are formed by spiral structures and eccentric cylindrical structures connected alternately, and an inner surface of a stator changes periodically along the axial direction and the radial direction of the rotors, achieving the volume pulsed deformation plasticizing and conveying of the materials during engaged rotation of the two or three engaged eccentric rotors. The device's eccentric rotors are all formed by length-varying spiral structures and eccentric cylindrical structures connected alternately; the spiral structures of the eccentric rotors are engaged to each other; the axial positions of eccentric cylindrical structures of the two or three rotors are the same. The present invention can implement extrusion of polymer materials or implement, in combination with a plunger injection unit, injection molding of polymer materials, and have many features such as desirable mixing and plasticizing effects for materials, a short thermo-mechanical course, low power consumption, and wide adaptability.

The present invention discloses a biaxial or tri-axial eccentric rotor volume pulsed deformation plasticizing method and device. The method is characterized in that: the conveying volume of materials formed between two or three engaged eccentric rotors, which are formed by spiral structures and eccentric cylindrical structures connected alternately, and an inner surface of a stator changes periodically along the axial direction and the radial direction of the rotors, achieving the volume pulsed deformation plasticizing and conveying of the materials during engaged rotation of the two or three engaged eccentric rotors. The device's eccentric rotors are all formed by length-varying spiral structures and eccentric cylindrical structures connected alternately; the spiral structures of the eccentric rotors are engaged to each other; the axial positions of eccentric cylindrical structures of the two or three rotors are the same. The present invention can implement extrusion of polymer materials or implement, in combination with a plunger injection unit, injection molding of polymer materials, and have many features such as desirable mixing and plasticizing effects for materials, a short thermo-mechanical course, low power consumption, and wide adaptability.

A method for producing a foam-molded product by using a plasticizing cylinder, includes: plasticizing and melting the thermoplastic resin to provide the molten resin in a plasticization zone of the plasticizing cylinder; introducing a pressurized fluid containing the physical foaming agent at a fixed pressure into a starvation zone of the plasticizing cylinder to retain the starvation zone at the fixed pressure; allowing the molten resin to be in the starved state in the starvation zone; bringing the molten resin in contact with the pressurized fluid containing the physical foaming agent at the fixed pressure, in the starvation zone in a state in which the starvation zone is retained at the fixed pressure; and molding the molten resin having been brought in contact with the pressurized fluid containing the physical foaming agent into the foam-molded product.

A plasticizer includes a drive motor, a flat screw that has a groove forming surface where a groove is formed and is rotated by the drive motor, a barrel which has a groove facing surface that faces the groove forming surface and in which a communication hole is formed, and a heater that heats resin pellets supplied to the space between the flat screw and the barrel, and at least one of the flat screw and the barrel is at least partially formed of a transparent member, and the resin pellets between the flat screw and the barrel is visible through the transparent member.