Injection pressure simulation

This class implements a rudimentary simulation of the melt pressure of an injection process. For this purpose, a pressure sensor is simulated, which is synchronized into the controller via an analogue interface (preferably FB_InputAnalog16).

Internally, a distinction is made in the class between the metering phase and the injection phase. For this purpose, both the rotary drive of the metering screw and the linear thrust drive must be provided in the simulation by an FB_SimAxCommon based axis.

Syntax:

FUNCTION_BLOCK FB_SimInjectionMeltPressure

I/O variables

Name	Type	Direction	Description
AnalogValue	INT	Output	The simulated pressure as an analog value.
EC.WcState	BOOL	Output	The simulated Working Counter State.
EC.Toggle	BOOL	Output	The simulated toggle bit.
EC.InfoDataState	UINT	Output	The simulated Device State.
EC.AdsAddr	AMSADDR	Output	The simulated ADS address.

Properties

Name	Type	Access	Description
AutoAdjustMeteringFactor	BOOL	Get, Set	If TRUE, the `MeteringFactor` is adjusted to the difference between the metered plastic and the linear thrust axis position after the metering process. This option is used to quickly calibrate the metering factor when activated for a short time. Notice If activated permanently, this option tends to incrementally reduce the `MeteringFactor.`
Cavity	LREAL	Get, Set	Simulated cavity in length units of the linear thrust axis (typ. [mm]).
CycleTime	LREAL	Get, Set	Cycle time with which the simulation is called.
Enable	BOOL	Get, Set	If not TRUE, the sensor does not respond to any movements of the linked axes.
InjectionResistance	LREAL	Get, Set	Resistance in pressure units (typ. [bar]) during injection by e.g. an upstream injection nozzle.
Injector	I_SimAxCommon	Get, Set	Interface to the linear thrust axis. The assignment of a simulated axis is mandatory.
IsInjecting	BOOL	Get	TRUE if the simulation has detected an injection process and is actively simulating it.
IsMetering	BOOL	Get	TRUE if the simulation has detected a metering process and is actively simulating it.
Metering	I_SimAxCommon	Get, Set	Interface to the rotary metering screw. The assignment of a simulated axis is mandatory.
MeteringFactor	LREAL	Get, Set	Specifies the increase in metered plastic during the dispensing process. The value is measured in length units of the linear thrust axis per revolution of the rotary metering screw (typ. [mm/360°]).
Pressure	LREAL	Get	Current simulated pressure value.
PressureFactor	LREAL	Get, Set	Melt pressure generated per length unit of the linear thrust axis (typ. [bar/mm]). This value represents the compressibility of the liquid injection mass.
ShrinkingFactor	LREAL	Get, Set	The larger this factor is selected, the faster the plastic shrinks during simulated cooling. Cooling begins as soon as the filling volume of the cavity is reached.
WipeAfterMetering	BOOL	Get, Set	If TRUE, the metered volume is synchronized to the current position of the linear thrust axis after the metering process has been completed. This option improves the stability of the simulation process. This prevents excess pressures arising from incorrectly set back pressure control from influencing the start of the injection process.

Methods

Name	Description
Cyclic()	Cycle method

Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT v3.1.4024.71	PC or CX (x64, x86)	Tc3_PlasticFunctions (>= v12.12.0.0)