Method for determining a value for the description of the compression of a moldable material

Patent metadata

Field	Value
Publication number	US-2020156300-A1
Application number	US-202016748304-A
Country	US
Kind code	A1
Filing date	Jan 21, 2020
Priority date	May 11, 2015
Publication date	May 21, 2020
Grant date	—

Abstract

In a method for determining at least one parameter for the description of the compression behavior of a material processed in a molding machine, at least a part of the processed material is introduced into a mold cavity via a distribution system and a gate, and the processed material solidifies in the mold cavity. A compression test is performed in which a volume storing the material is modified and a measurement of the resulting pressure modification is conducted or a pressure applied onto the material is modified and a measurement of the resulting modification of the volume is conducted. A parameter for the description of the compression behavior is calculated based on the result of the compression test by using a mathematical model. The compression test is conducted when the gate is at least substantially solidified or when the hot runner is closed.

First claim

1 - 11 . (canceled)

12 . A method for operating a molding machine, wherein depending on at least one parameter for the description of a compression behavior of a material processed in the molding machine, the method comprises:
calculating a realistic injection volume and/or a realistic injection volume flow, and/or calculating a decompression lift, and/or calculating a dwell time of the melt in the molding machine, and/or parameterizing a pressure regulator, and/or determining a pressure dependency of the compression behavior, and/or determining a temperature of the melt, and/or controlling the velocity of the plasticizing screw so that a predetermined filling volume flow is reached, and/or determining a material characteristic of the melt, wherein the material characteristic is a composition, a phase state, a viscoelasticity, a solids content, a proportion of low-molecular substances, or a chemical modifications of the polymer structure.

13 . (canceled)

14 . The method according to claim 12 , wherein the molding machine is one of an injection molding machine or a transfer molding machine.

15 . The method according to claim 12 , further comprising determining the at least one parameter for the description of the compression behavior of the material processed in the molding machine, the determining comprising:
introducing at least a part of the processed material into a mold cavity via a distribution system and a gate, wherein the processed material solidifies in the mold cavity; executing at least one compression test in which a modification of a volume storing the material is made and a measurement of a resulting pressure modification or a pressure applied onto the material is modified and a measurement of the resulting modification of the volume storing the material is conducted; and calculating the at least one parameter for the description of the compression behavior based on the result of the at least one compression test by using a mathematical model, wherein the at least one compression test is conducted when the gate is at least substantially solidified or—if the molding machine comprises a closable hot runner arranged at the gate—when the hot runner is closed, so that a dead volume which reaches till the gate is considered in the calculation of the at least one parameter for the description of the compression behavior.

16 . The method according to claim 15 , wherein the molding machine comprises a plasticizing screw arranged in a plasticizing cylinder and functioning as a piston, wherein the modification of the volume storing the material is effected by modifying a position of the plasticizing screw in the plasticizing cylinder.

17 . The method according to claim 15 , wherein the molding machine comprises a plasticizing screw arranged in a plasticizing cylinder and functioning as a piston, wherein the modification of the pressure applied onto the material is effected by the plasticizing screw.

18 . The method according to claim 16 , wherein the molding machine comprises a piston arranged in a material storage space, wherein the modification of the volume storing the material is effected by modifying a position of the piston in the material storage room.

19 . The method according to claim 15 , wherein the molding machine comprises a piston arranged in a material storage space, wherein the modification of the pressure applied onto the material is effected by the piston.

20 . The method according to claim 15 , wherein the mold cavity is provided in a molding tool, wherein the modification of the pressure and/or the volume is effected by a movable molding tool element, preferably a core pull or an ejector.

21 . The method according to claim 15 , wherein at least two compression tests are executed under different boundary conditions.

22 . The method according to claim 15 , wherein the at least one determined parameter of the compression behavior is displayed.

23 . The method according to claim 15 , wherein the at least one compression test is executed independently from a production cycle of the molding machine.

24 . The method according to claim 15 , wherein the at least one compression test is executed in a production cycle of the molding machine.

25 . The method according to claim 24 , wherein the at least one compression test is executed in the form of a pressure reduction at the end of a holding pressure phase and/or during a pressure relief before or after a dosing operation.

Assignees

• Engel Austria Gmbh

Inventors

• Pillwein Georg
• Markut-Kohl Ruth

Classifications

• B29C45/7693 Primary

  using rheological models of the material in the mould, e.g. finite elements method · CPC title

• B29C45/77

  of velocity or pressure of moulding material · CPC title

• B29C2945/76107

  volume · CPC title

• G01N33/44

  Resins; Plastics; Rubber; Leather · CPC title

• B29C2945/76287

  Moulding material · CPC title