JP2006044184A - Control method for feeder and plasticator of on-line blend injection molding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control method for the feeder and the plasticator of an on-line blend injection molding machine which stabilizes the supply amount of a resin material fed from a feeder even in the case of the existence of mechanical vibration to enable the supply of the resin material high in precision and is also capable of easily changing the number of rotations of a screw or the supply amount of the feeder. <P>SOLUTION: In this feeder control method for the on-line blend injection molding machine, the two types, of a constant flow type wherein the number of rotations of a motor is constant and a loss-in-weight type wherein a resin material is supplied while its weight is being measured, are provided, and the supply of resin material according to these two types are selectively performed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a feeder of an on-line blend injection molding machine for plasticizing a resin material from a feeder by a plasticizing device, supplying the plasticized resin to an injection device through an accumulator, and a control method for the plasticizing device. .

  The on-line blend injection molding machine is recently used because the resin material supplied to the injection molding machine does not need to be pelletized, can be supplied directly from the resin material manufacturing process, and the pellet manufacturing process can be omitted. It is like that.

An online blend injection molding machine uses, for example, an extruder as a plasticizer, and therefore, a feeder for supplying resin raw materials is used between the feeder and the plasticizer (that is, the extruder), and the material resin in the hopper is supplied. The resin material is supplied to the plasticizing apparatus while measuring the weight.
JP-A-5-131509 JP-A-7-112467

In the conventional method, the measurement result of the load cell becomes unstable due to mechanical vibration generated in the mold opening / closing process, injection process, etc. of the injection molding machine, and the measurement accuracy may be affected depending on the situation.
For example, when there is little or almost no mechanical vibration as shown by the line (A) in FIG. 2, the weight decreases smoothly over time. However, when there is mechanical vibration as shown by the line (B) in FIG. 2, the weight moves up and down due to the vibration, and its decrease becomes unstable.

  Further, in the operation of the extruder, the resin material supply amount from the feeder and the extrusion amount are almost the same value, and Q / Ns (extrusion amount / screw rotation speed) can greatly affect the plasticized state of the resin material. Are known. However, in the extruder, the screw rotation speed and the feeder operation are not interlocked, and in order to keep Q / Ns constant, the operation of the screw and the feeder is complicated, and it is easy to cause an operation error and requires skill.

  This invention stabilizes the amount of resin material supplied from the feeder, enables high-precision resin material supply, and interlocks the screw rotation speed of the extruder with the feeder to facilitate the screw rotation speed or the supply amount of the feeder. It is an object of the present invention to provide an on-line blend injection molding machine feeder and a plasticizing apparatus control method that can be changed to the above.

  In order to achieve the above-mentioned object, the present invention firstly plasticizes a resin material from a feeder by a plasticizing device, and supplies the plasticized resin to an injection device through an accumulator to perform injection molding. In the feeder control method of the molding machine, there are two types of feeder control, a constant flow method with a constant motor speed and a loss-in-wait method that supplies while measuring the weight of the resin material. The feeder control method of the on-line blend injection molding machine is characterized by supplying the material.

  According to a second aspect of the present invention, the feeder is a constant flow rate method with a constant rotational speed when mechanical vibration is generated, such as a mold opening / closing process of an injection molding machine, and a loss-in-weight method that measures the weight of the resin material when mechanical vibration is small. This is a feeder control method for an on-line blend injection molding machine.

  Further, as a third invention, the plastic material is controlled from a feeder by a plasticizing device, and the plasticized resin is supplied to the injection device through an accumulator to control the plasticizing device of an on-line blend injection molding machine that performs injection molding. In the method, the plasticizing apparatus is an extruder having a screw in a plasticizing barrel, and when the number of rotations of the screw is changed, the resin material supply amount of the feeder is changed in accordance with the screw speed. The feeder control method of the molding machine was used.

  And as 4th invention, when the resin material supply amount of a feeder was changed, it was set as the plasticizer control method of the online blend injection molding machine characterized by changing the rotation speed of the screw of an extruder according to this. .

  Furthermore, as a fifth invention, when the screw rotation speed or the resin material supply amount of the feeder is changed, either one of Q or Ns is changed in accordance with a preset value of Q / Ns. If it is possible, it becomes a suitable method for controlling the plasticizing device of an on-line blend injection molding machine.

  Furthermore, as a sixth invention, when the set Q / Ns is changed, a plasticizer control method suitable for an on-line blend injection molding machine can be used if the screw rotation speed or the resin material supply amount or both can be changed. It is.

  According to the present invention, the amount of material resin supplied from the feeder is stabilized, high-precision material resin can be supplied, and the screw rotation speed of the extruder and the feeder are linked. It became the feeder and plasticizing device control method of an on-line blend injection molding machine capable of easily changing the supply amount. In addition, it is possible to provide a control method for a feeder and a plasticizing device of an on-line blend injection molding machine that enables a stable supply of resin raw materials by changing the control method of the feeder during machine operation with mechanical vibration. .

  Referring to FIG. 1, an embodiment of the present invention will be described. Reference numeral 1 denotes an on-line blend injection molding machine, which passes through or once passes through an extruder 3 which is a plasticizer equipped with a feeder 2 and a resin material plasticized by the extruder 3. The accumulator 4 is stored, and an injection molding machine (only the injection device 5 is described) for injection molding the plasticized resin sent from the accumulator 4. The feeder 2 is driven by a motor 6 and can be selectively used with two control systems, a constant flow system with a constant motor rotation speed and a loss-in-wait system that supplies while measuring the weight of the resin material. . The feeder 2 is attached to the extruder 3 through a load cell 7, and the load cell 7 measures the weight of the resin material 9 by measuring the weight of the resin material 9 in the hopper 8 (the weight of the entire feeder 2). This is a sensor for measuring the supply amount of the material and calculating it within the molding period control device 15.

  The screw 12 of the extruder 3 is driven through the gear box 11 by the rotation of the motor 10, and the resin material supplied from the feeder 2 is shearing heat due to the rotation of the screw 12 and a heater or the like (not shown). It is plasticized by the heating device and is passed through or accumulated in the accumulator 4 as plasticized resin, and the valve 13 is opened during the injection process of the injection molding machine, and the plasticized resin is supplied to the injection device 5 and injected by the plunger 14. The

The online blend injection molding machine 1 is controlled by a molding machine control device 15, and the motor 6 for driving the feeder and the motor 10 for driving the extruder 3 are respectively connected via a motor driver 16 in the molding machine control device 15. Connected to the motor controller 17 and controlled.
The signal from the load cell 7 is led to the voltage module 18 in the molding machine controller 15 with the detected weight value as the voltage V, and is analog / digital converted (A / D converted), and surrounded by a chain line via the bus 19. The data is converted by the data conversion means 21 of the detection unit 20 and stored in the storage unit 22. The storage unit 22 includes a data setting unit (not shown). For example, the relationship between the weight (voltage V) and time when there is little mechanical vibration as shown in FIG. Data indicating (A) is set.

  Therefore, for example, data indicating the relationship (B) between the weight (voltage V) and time when there is mechanical vibration stored in the storage unit 22 by the data conversion unit 21 and data set in the storage unit 22 in advance. The comparison calculation means 23 performs the comparison calculation, and the result is displayed as an image on the display monitor on the display / operation panel 25 via the bus 19 from the display means 24.

  For the control of the feeder driving motor 6 described above, a method of selectively switching between a constant flow method with a constant motor speed and a loss-in-weight method of supplying while measuring the weight of the resin material is prepared. . The control for this is performed by a mold opening / closing process, an injection process, etc. in which mechanical vibrations are generated in advance from a control unit (not shown) of a molding machine control sequence for controlling the mold opening / closing, injection operation sequence, etc. The motor control unit 17 receives and determines a signal related to this process, and outputs a signal (mode) for switching the feeder control method to the motor driver 16 to act. That is, it is possible to select constant flow rate system control with a constant rotational speed by determining whether the process is (or is likely to generate vibration), or the process is free (or very small), or is a loss-in process. Select whether or not to select the wait method control.

  Further, the storage unit 22 has, for example, extruder screw rotation speeds Ns1, Ns2, Ns3,..., Extrusion amounts Q1, Q2. , Q2... Qn is set, and therefore, when a screw speed detector (not shown) changes the speed of the extruder screw from s1 to Ns2, this result is converted into data conversion means in the detection unit 20. 21 and stored in the storage unit 22, the comparison calculation means 23 calculates Q 2 / Ns 2, selects the feeder supply amount q 2 with respect to the extrusion amount Q 2, and outputs the bus 19, motor via the output means 26. It acts on the feeder motor 6 via the control unit 17 and the motor driver 16, and performs control in accordance with the feeder supply amount q2.

Similarly, when the feeder supply amount qn is changed, the extrusion amount Qn and the rotation speed Nsn of the extruder screw are selected and can be changed immediately. Further, when the screw rotation speed Nsn or the resin material supply amount qn of the feeder is changed, either one of Qn and Nsn can be changed in accordance with a preset value of Qn / Nsn.
Furthermore, when the set Qn / Nsn is changed, it is also possible to change the screw rotation speed Nsn, the resin material supply amount qn, or both.

  The calculation results described above or various operating condition data or detection data set in the storage unit 22 or the reduction status of the feeder raw material can be input and set by the display / operation panel 25. It can be displayed on the monitor screen as a display or an image.

  According to the embodiment of the present invention, the material resin supply from the feeder is selectively changed with respect to mechanical vibration, the resin supply amount is stabilized, and the material resin is supplied with high quantitative accuracy. In addition, since the screw rotation speed of the extruder and the feeder are linked, the feeder control and plasticization of the online blend injection molding machine that can easily change the screw rotation speed or the feeder supply amount. It becomes a control method. Furthermore, in the description of the above-described embodiment, the injection molding machine and the accumulator have been described by the embodiment of the hydraulic system, but of course not limited to this, the all-electric system or the electric / hydraulic hybrid system It is obvious that it may be an on-line blend injection molding machine of a system different from this embodiment example.

It is explanatory drawing which shows the outline | summary of an example to which the feeder and plasticizing apparatus control method of an online blend injection molding machine by this invention are applied. It is explanatory drawing which shows the outline | summary of the feeder of the on-line blend injection molding machine by this invention, and the plasticizing apparatus control method, and each with and without the mechanical vibration of the material resin weight in the feeder hopper (when vibration is very small) It is a figure for demonstrating the state with respect to time about a case.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Online blend injection molding machine 2 Loss weight type feeder 3 Extruder 4 Accumulator 5 Injection molding machine (injection apparatus)
6 Feeder Motor 7 Load Cell 8 Hopper 9 Resin Material 10 Extruder Motor 11 Gear Box 12 Extruder Screw 13 Valve 14 Plunger 15 Molding Machine Controller 16 Motor Driver 17 Motor Controller 18 Voltage Input Module 19 Bus 20 Detector 21 Data Conversion unit 22 Storage unit 23 Comparison operation unit 24 Display unit 25 Display / operation panel 26 Output unit

Claims (6)

  In the feeder control method of an online blend injection molding machine that plasticizes the resin material supplied from the feeder by a plasticizing device, supplies the plasticized resin to the injection device through an accumulator, and performs injection molding, the feeder control method is Online system characterized in that the constant flow rate method with a constant motor speed and the loss-in-wait method that supplies while measuring the weight of the resin material are used, and the resin material is selectively supplied by the two methods. Feeder control method for blend injection molding machine.   The feeder has a constant flow rate method with a constant rotation speed when mechanical vibration occurs in the mold opening / closing or injection process of the online blend injection molding machine, and a loss-in measuring the weight of the resin material when mechanical vibration is small. 2. The feeder control method for an on-line blend injection molding machine according to claim 1, wherein the control is performed by a weight system.   In an on-line blend injection molding machine plasticizing apparatus control method for plasticizing a resin material from a feeder by a plasticizing apparatus, supplying the plasticized resin to an injection apparatus through an accumulator, and performing injection molding, the plasticizing apparatus is A feeder control method for an on-line blend injection molding machine, characterized in that an extruder having a screw in a plasticizing barrel is used, and when the number of rotations of the screw is changed, the amount of resin material supplied to the feeder is changed accordingly.   4. The method of controlling a plasticizing apparatus for an on-line blend injection molding machine according to claim 3, wherein when the amount of the resin material supplied to the feeder is changed, the number of rotations of the screw of the extruder is changed accordingly.   When the screw rotation speed or the resin material supply amount of the feeder is changed, either one of Q or Ns is changed in accordance with a preset value of Q / Ns (extrusion amount / screw rotation speed). The method of controlling a plasticizing apparatus for an on-line blend injection molding machine according to any one of claims 3 and 4, wherein: 5. The online blend injection molding according to claim 3, wherein when the set Q / Ns is changed, the screw rotational speed or the resin material supply amount or both are changed. Machine plasticizing device control method.

Images