Introductory example
Description of the example
Introduction
Transfer device
The following example covers all the phases for setting up a TSX CAY axes control application. It complements the set-up methodologies.
A transfer device evacuates the parts during machining output. This device consists of a grab which can move through the air along a plane (X, Y axes) parallel to the ground.
As soon as a part appears on evacuation conveyor A, the grab automatically retrieves it and deposits it on conveyor B or C depending on the type of part. The grab then returns to the waiting position until a new machined part needing to be picked up is detected.
The following figure illustrates this transfer device:
C1
Machining tool
C2
C3
C4
Conveyor B
Conveyor A
Conveyor C
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TLX DS 57 PL7xx
Inputs/outputs
Introductory example
The inputs / outputs are as follows:
I/O
C1
C2
C3
C4
Description
Machined part detection cell
Part type identification sensor.
Grab open / grab closed detection sensor.
Part edge detection cell (located in the grab), connected to the module’s event input.
ENC0
ENC1
Incremental encoder in the X axis position.
Incremental encoder in the Y axis position.
O/C grab Grab Open / Close control.
Application
Grafcet
The application Grafcet is as follows:
0
1
2
3
4
5
6
Reference point
Referenced axes
Move to wait position
Detection of a machined part
Movement towards conveyor A
Edge of part detected and grabber in stop position
Grabber closed
Type 1 part and grabber closed
Moving on conveyor B
Grabber in stop position
8
Type 2 part and grabber closed
Moving on conveyor C
Grabber in stop position
Grabber opening
Grabber open
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Introductory example
Trajectory description
The following diagram shows the trajectory of the grab:
Y_LMAX
Conveyor A
3
2
5
Wait position
7
4
Conveyor B
6
Conveyor C
1
X_LMIN
X_LMAX
Y_LMIN
1 Reference point at speed Vp0,
2 Movement at speed Vret to waiting position (Xatt, Yatt) with stop,
3 Movement towards conveyor A (XA, YA) at speed VA, until the machined part is detected,
4 Movement towards conveyor B (XB, YB) at speed VB, with stop,
6 Movement towards conveyor C (XC, YC) at speed VC, with stop,
5, 7 Movement to waiting position (Xatt, Yatt) at speed Vret, with stop.
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TLX DS 57 PL7xx
Operator dialogue front panel
Introductory example
The following controls grouped together on a front panel, are used to control the moving part manually when the installation is faulty. The controls and the LEDs are managed by one discrete input module and one discrete output module.
Auto X Y Error
Manu Choose axis
Start cycle
Reference point
Acq.
Error
Stop cycle Reverse Forward
Emergency stop
Open grabber
Close grabber
Auto / Manu: Operating mode selection switch.
Start cycle: Executes the automatic cycle.
Stop cycle: Stops the automatic cycle.
X / Y axis selection: For selection of the axis to be controlled in manual mode.
Reference point: Manual reference point on the selected axis.
Forward / Reverse: Control for manual movement of the selected axis in a positive or negative direction.
Error: LED for all hardware and application errors.
Acq. Error: Fault acknowledgement control.
Emergency stop: Immediate stop of the moving part whatever the selected mode.
Open grab: Control for opening grab.
Close grab: Control for closing grab.
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