Siemens SINUMERIK 840D sl Function Manual page 205

2.6 Combine short spline blocks
Function
During the processing of splines short blocks can so occur, that the path velocity for the
interpolation of these spline blocks must be reduced. This is alao the case, when the spline
actually has a long, smooth curve.
The "Combine short spline blocks" function allows you to combine these spline blocks such
that the resulting block length is sufficient and does not reduce the path velocity.
Note
NC block compressor
The NC-block-compressor (COMPON, COMPCURV or COMPCAD) cannot be employed while
compressing spline blocks, since with this only linear blocks can be compressed.
Activation
The function "overview of short spline blocks" can be activated for following cases
independent of each other:
• BSPLINE active
• BSPLINE/ORICURVE active
• CSPLINE active
The activation is done using machine data:
MD20488 $MC_SPLINE_MODE (setting for spline interpolation).
Bit
0
1
2
Boundary conditions
• NC-blocks can be combined only if no other details have been programmed except the
Basic logic functions: Continuouspath Mode, Exact Stop, LookAhead (B1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Value Meaning
0 Overview of short spline blocks in the case of BSPLINE not active.
1 Overview of short spline blocks in the case of BSPLINE active.
0 Overview of short spline blocks in the case of BSPLINE/ORICURVE not active.
1 Overview of short spline blocks in the case of BSPLINE/ORICURVE active.
0 Overview of short spline blocks in the case of CSPLINE not active.
1 Overview of short spline blocks in the case of CSPLINE active.
axial motions and the feed rate. If, for example, auxiliary functions are programmed,
which must be given to the PLC, then this block cannot be omitted, since it must be active
in the interpolator. This is analogous to the possible compression of G1-blocks with the
compressors COMPON, COMPCURV and COMPCAD.
Detailed description
2.6 Combine short spline blocks
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