Description of the Example

Introduction

The following example covers all the phases for setting up a TSX CAY axes control application. It complements the set-up methodologies.

Transfer Device

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:

Inputs/Outputs

The inputs / outputs are as follows:

I/O	Description
C1	Machined part detection cell
C2	Part type identification sensor.
C3	Grab open / grab closed detection sensor.
C4	Part edge detection cell (located in the grab), connected to the module’s event input.
ENC0	Incremental encoder in the X axis position.
ENC1	Incremental encoder in the Y axis position.
O/C grab	Grab Open / Close control.

Application Grafcet

The application Grafcet is as follows:

Trajectory Description

The following diagram shows the trajectory of the grab:

Reference point at speed Vp0,

Movement at speed Vret to waiting position (Xatt, Yatt) with stop,

Movement towards conveyor A (XA, YA) at speed VA, until the machined part is detected,

Movement towards conveyor B (XB, YB) at speed VB, with stop,

Movement towards conveyor C (XC, YC) at speed VC, with stop,

5, 7

Movement to waiting position (Xatt, Yatt) at speed Vret, with stop.

Operator Dialogue Front Panel

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 / 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.