The present disclosure discloses an ultrasonic online nondestructive measurement method for a melt density in injection molding, which solves the problems of difficult installation, high cost, influence on product surface quality, and the like existing in an existing density measurement method. According to the present disclosure, an ultrasonic velocity is obtained from a time domain signal with reference to time domain and frequency domain signal analysis of ultrasonic echo signals, an acoustic impedance is calculated by full spectrum analysis of a frequency domain signal, and the melt density is calculated from a correlation of the ultrasonic velocity, the acoustic impedance, and the density. The method has the advantages of having high measurement accuracy and being nondestructive, online and low in cost, and has a great application value in the injection molding industry.

Non-time dependent calculated variables based on measured strain are used to effectively determine an optimal hold profile for an expanding crosslinking polymer part in a mold cavity. A system and/or approach may first inject molten expanding crosslinking polymer into a mold cavity, then measure strain at the mold cavity or at another location within the injection molding system, and then calculate at least one non-time dependent variable during an injection molding cycle. Next, the system and/or method commences a hold profile for the part, and upon completing the hold profile, the part is ejected from the mold cavity, whereupon a cure profile is commenced.

Non-time dependent measured variables are used to effectively determine an optimal hold profile for an expanding crosslinking polymer part in a mold cavity. A system and/or approach may first inject molten expanding crosslinking polymer into a mold cavity, then measure at least one non-time dependent variable during an injection molding cycle. Next, the system and/or method commences a hold profile for the part, and upon completing the hold profile, the part is ejected from the mold cavity, whereupon a cure profile is commenced.

A method for determining positions of a real moulding material front during a process to be carried out with a moulding machine, wherein a simulation progression (SV) of a variable characteristic of the process is calculated, positions of a simulated moulding material front are determined from the simulation, the real process is carried out, and at least one measurement progression (MV) of the at least one characteristic variable is measured directly or indirectly, a transformation is chosen, which has at least one parameter (?V, kp, V.sub.unknown), the transformation is applied to the at least one simulation progression (SV), with the result that a transformed simulation progression (tSV) is formed, and a parameter value is determined for the parameter (?V, kp, V.sub.unknown) such that a deviation between the measurement progression (MV) and the transformed simulation progression (tSV) is minimized according to a predetermined error measure or according to an operator input.

An injection molding machine includes a plasticizing unit having a plasticizing cylinder and a material-conveying device that is movable in the plasticizing cylinder and powered by a material-conveying drive, a material-conveying drive control, which is coupled with the material-conveying drive and is designed to control operating parameters of the material-conveying drive, a closing unit having an injection molding tool that is connected with an outlet nozzle of the plasticizing cylinder, as well as a closing unit control, which is coupled with a closing unit drive of the closing unit and is designed to control operating parameters of the closing unit drive. The injection molding machine further includes one or more dieletric or acoustic sensors which are disposed in the cavity of the injection molding tool or close to the cavity of the injection molding tool and are designed to determine the dielectric polarizability, mobility of free load carriers and/or acoustic material responses of a molding material in the cavity of the injection molding tool. A sensor control is coupled with the dielectric or acoustic sensor(s) and is designed to ascertain a time-dependent degree of crystallization and a time-dependent median temperature of the molding material in the cavity of the injection molding tool from the dielectric polarizability, mobility of free load carriers and/or acoustic material responses determined by the dielectric sensor(s) and, depending on the ascertained degree of crystallization and the ascertained median temperature, to actuate the material-conveying drive control and/or the closing unit control to adjust the operating parameters of the material-conveying drive and/or of the closing unit drive.

An in-mold vibratile injection compression molding method and molding apparatus thereof are described. While performing a filling stage, a first piezoelectric actuator and a second piezoelectric actuator are use to vibrate the molding material along at least two directions for precisely filling the molding material into the micro-structure by adjusting the filling flow velocity of the molding material associated with the proper molding material temperature and by maintaining a molding material temperature of a skin solidified layer in the cavity between a glass transition temperature and a melting temperature in order to avoid the form error, to increase the groove filling rate and to improve the residual stress.

A time variation of an internal pressure of the molding cavity of a multi-phase injection molding machine is detected and represented as an internal pressure graph. An internal pressure graph recorded during a production cycle that produced an injection molded part satisfying a predefined quality characteristic is used as a reference graph. If the internal pressure graph of the current production cycle exceeds a predefined threshold value, then a current machine parameter is changed so as to adapt an internal pressure graph of a subsequent production cycle to the reference graph. Each phase of the production cycle is assigned its own machine parameter determined to have a significant impact on the quality of the parts produced. The assigned machine parameters are changed in a predefined order in a plurality of production cycles wherein exactly one assigned machine parameter is changed per production cycle.

A manufacturing method of a semiconductor device includes the steps of: preparing a lead frame; mounting a plurality of semiconductor chips on the lead frame; and sealing one portion of the lead frame with a sealing resin. The resin-sealing step includes the step of: disposing the lead frame, molds having main surfaces on which cavity parts are formed, the lead frame being disposed on the main surface of the heated molds; injecting a resin in the main surfaces of the heated molds so as to seal the one portion of the lead frame with the sealing resin; and taking out the lead frame from the heated molds. In the taking-out step, while the lead frame is taken out, the main surfaces of the molds are inspected by using a sensor, and the sensor is cooled and formed integrally with an arm used for taking out the lead frame.

Non-time dependent measured variables are used to effectively determine an optimal ejection time of a part from a mold cavity. A system and/or approach may first measure at least one non-time dependent variable during an injection molding cycle. The part is ready to be ejected from the mold upon the measured variable reaching a threshold value indicative of, for example, a part temperature dropping below an activation temperature.

The present disclosure provides a molding machine and a method of molding a part. The molding machine may include multiple molding systems (e.g., extruders) for pumping molten material into one or more mold cavities. The multiple molding systems may pump the same material or different materials into the one or more mold cavities. The multiple molding systems may be individually and/or collectively controlled. A method of molding a part may include pumping material into one or more mold cavities via multiple molding systems, ceasing pumping material into the one or more mold cavities when one or more pressures associated with the multiple molding systems are achieved, and releasing a molded part from the one or more mold cavities after the one or more pressures are achieved.