A method for generating a signal indicative for nozzle maintenance, including feeding modeling material through a feed channel of a printhead to a nozzle of the printhead in a three-dimensional modeling system, determining a parameter indicative of a fluid resistance of modeling material within the nozzle. Determining the parameter includes determining a flowrate of the modeling material within the feed channel, determining a pressure exerted on the modeling material within the feed channel and determining a pressure exerted on the modeling material outside the feed channel, determining a pressure difference between the pressure exerted on the modeling material within the feed channel and the pressure exerted on the modeling material outside the feed channel, and calculating the parameter from the determined flow rate and the determined pressure difference. A method and system for three-dimensionally modeling a three-dimensional object using the method for generating a signal indicative for nozzle maintenance.

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.

A system, method and apparatus for controlling an injection unit to transfer a material to a mold cavity includes a first actuator and a second actuator, and a controller that is operatively connected to the first actuator and the second actuator. The first and second actuators are coupled to a ram of the injection unit. The first actuator rotates the ram within the barrel, and the second actuator translates the ram within the barrel. During a material fill stage of an injection cycle, the controller controls the first actuator to rotate the ram within the barrel. The controller also controls the second actuator to translate the ram within the barrel, and controls the second actuator to retract the ram away from a nozzle of the injection unit while exerting a compression force on the ram towards the nozzle.

An injection molding machine includes: a screw inserted in an injection cylinder and configured to be movable in the axial direction; a motor configured to move the screw; a torque detection unit configured to detect the torque of the motor; a position detection unit configured to detect the position of the screw; a motor drive control unit configured to drive the motor while imposing torque limitation so that the motor's torque will not exceed a limit torque, to thereby advance the screw to the foremost position in the direction of injection; and a determination unit configured to determine that unmelted resin remains inside the injection cylinder if the moving speed of the screw becomes lower than or equal to a predetermined speed while the screw is advancing to the foremost position.

There are provided an apparatus for taking out a molded product that allows a physical amount such as the mass of the taking portion to be easily acquired with a relatively simple configuration. A posture reversing mechanism is provided between the elevating arm and the taking portion to change the direction of the taking portion between an unreversed state in which the taking portion is directed to be able to take hold of the molded product molded in the die, and a reversed state in which the length of the taking portion in the vertical direction is shorter than that in the unreversed state. A sensor detects vibration of the elevating arm. A mass estimating section estimates the mass of the taking portion on the basis of vibration of the elevating arm detected by the sensor when the taking portion is in the reversed state.

An injection device according to one embodiment of the present invention monitors the linear torque of a linear motor and the rotary torque of a rotary motor using a first detection unit for detecting the linear torque and a second detection unit for detecting the rotary torque while controlling the linear motor and the rotary motor so that a bush is spline-fitted to a screw.

An injection molding machine includes a servomotor, a servo amplifier, and a control device. The servo amplifier includes a first switching element and a second switching element. The molding cycle includes a first period in which the servomotor is rotated and a second period in which the servomotor is not rotated. The servomotor is configured to allow motor rotation control, servo-off control, and zero-speed control to be executed thereon. The control device executes the motor rotation control in the first period and executes the servo-off control or the zero-speed control in the second period.

In an injection device according to an embodiment, each of a plurality of outer peripheral protrusions of a screw is formed with an outer peripheral protrusion inclined surface, and each of a plurality of inner peripheral protrusions of a through-hole of a bush is formed with an inner peripheral protrusion inclined surface. The injection device advances the bush until a linear-motion torque exceeds a linear-motion torque threshold, and, if a rotation torque exceeds a rotation torque threshold before the linear-motion torque exceeds the linear-motion torque threshold, ends control processing when the linear-motion torque exceeds the linear-motion torque threshold.

An embodiment of the present invention provides an injection device including a screw that includes a plurality of outer circumferential protrusions, each of the plurality of outer circumferential protrusions being provided with an outer circumferential protrusion slope and a second outer circumferential protrusion slope. A bush of the injection device includes a plurality of inner circumferential protrusions, each of the plurality of inner circumferential protrusions being provided with an inner circumferential protrusion slope and a second inner circumferential protrusion slope. A rear end of each of the plurality of outer circumferential protrusions and a front end of each of the plurality of inner circumferential protrusions include no flat surface.

An injection molding system includes: a first extruding member that extrudes a first molded article from a mold; a robot that transfers the first molded article extruded from the mold to an assembling position in relation to a second molded article in the mold; a second extruding member that extrudes the second molded article from the mold towards the first molded article retained at the assembling position by way of the robot, and assembles the second molded article to the first molded article; and a load detection unit that detects load applied to the second extruding member, in which defect discrimination of the first molded article, the second molded article, or an assembled state of the first molded article and the second molded article is performed, based on load detected by the load detection unit when the second molded article is assembled to the first molded article.