HEIDENHAIN TNC 426 CB, Technical Manual

Page: 751 / 1135

December 2001 Tool Changer 6 – 421
6.21.4 Controlling the Tool Changer
You program the control of the tool changer in the PLC.
This includes:
n
Positioning of the changing arm and carousel
n
Tool change sequence
The NC handles the tool management. This includes:
n
Tool life
n
Pocket assignment
n
Evaluation of the TOOL DEF blocks
n
Evaluation of the TOOL CALL blocks
The NC and PLC communicate through markers and words.
For execution of the TOOL CALL block, the NC takes the tool geometry data
from the tool table:
7 7 7 7 Activate with M4538 the geometry of the tool defined in W264. With this
marker you make sure that the current tool geometry is always active even
if the tool change sequence is cancelled.
CAUTION: Activate only together with an M/S/T/Q strobe or when the axis
is stationary!
With the TOOL DEF block you can pre-position the tool changer:
7 7 7 7 After a tool has been changed, program the next tool with TOOL DEF.
7 7 7 7 Evaluate the tool and pocket number and pre-position the tool changer to
the follow-up tool.
Calling an NC
program with TOOL
CALL With the NC block TOOL CALL you can call an NC program of your own
definition:
7 7 7 7 With the command TC = <path name>\<file name> in the
PLC:\NCMACRO.SYS file, define the name of the NC program to be called.
To synchronize the current machine status and the look-ahead calculation with
an NC macro call, (See “NCMACRO.SYS” on page 7 – 44).
The tool geometry is not taken over then. You must program a TOOL CALL at
another place to update the tool data.
Program example: Positioning to the tool change position:
7 7 7 7 Preferably file the program in the PLC partition so that it cannot be changed
by the end user.
The tool data in the current program are not active. They must be requested
with FN18 (See "PLC Programming” on page 7 – 3).
7 7 7 7 In the called program, enter a TOOL CALL so that the tool data become
active and a T strobe is transferred to the PLC.
With FN17 you can overwrite the software limit switch for the tool-change
position. If you use FN18 to call the programmed position after the TOOL
CALL, you can program a continuous positioning movement of the spindle
from the tool magazine to the next position (M112).