GSK 980TDi, User Manual

Page: 131 / 570

Official GSK Agents in South Africa
Tel: +27 11 626 2720, design@efamatic.com
Chapter 3 G Commands
115
Ⅰ
Programming
mm/inch) without sign symbol, and the direction of tool infeed is determined by ns block
traverse direction. The value of system parameter No.051 is regarded as the tool infeed
clearance when W(
Δ d) is not input.
e: it is Z tool retraction clearance in roughing, its value: 0~99.999 （ IS_B ） /0~99.9999 （ IS_C ）
(unit: mm) without sign symbol, and the direction of tool retraction is opposite to that of tool
infeed, the specified value e is reserved after R(e) is executed. The value of system
parameter No.052 is regarded as the tool retraction clearance when R(e) is not input.
ns: Block number of the first block of finishing path.
nf: Block number of the last block of finishing path.
Δ u ： it is X finishing allowance in roughing, its range: -99999.999~99999.999(IS_B ）
/-9999.9999~9999.9999(IS_C) (X coordinate offset of roughing contour corresponding to
the finishing path, i.e. X absolute coordinate difference between A’ and A.(diameter, unit:
mm/inch, with sign symbol).
Δ w
：
it is Z finishing allowance in roughing, its range: -99999.999~99999.999(IS_B
）
/-9999.9999~9999.9999(IS_C) (Z coordinate offset of roughing contour corresponding to
the finishing path, i.e. Z absolute coordinate difference between A’ and A.(diameter, unit:
mm/inch, with sign symbol).
When K is not input or is not 1, the system does not check the program monotonicity except
that the Z value of starting point and end point of the arc or ellipse or parabola or the arc
is more than 180 degree; K=1, the system checks the program monotonicity.
F: Cutting feedrate; S: Spindle speed; T: Tool number, tool offset number.
M, S, T, F: They can be specified in the first G72 or the second ones or program ns
～
nf. M, S, T,
F functions of M, S, T, F blocks are invalid in G72, and they are valid in G70 finishing blocks.
Execution process:
①
X rapidly traverses to A’ from A point, X travel is Δ u, and Z travel is Δ w;
② X moves from A’ is Δ d( tool infeed), ns block is for tool infeed at rapid traverse speed
with G0, is for tool infeed at G72 feedrate F in G1, and its direction of tool infeed is
that of A
→ B point;
③ X executes the cutting feeds to the roughing path, and its direction is the same that of
X coordinate B
→ C point;
④
X, Z execute the tool retraction e (45°straight line)at feedrate, the directions of tool
retraction is opposite to that of tool infeed ;
⑤
X rapidly retracts at rapid traverse speed to the position which is the same that of Z
coordinate;
⑥ After Z tool infeed ( Δ d+e)again is executed, the end point of traversing tool is still on
the middle point of straight line between A’ and B’(the tool does not reach or exceed
B’), and after Z executes the tool infeed (
Δ d+e)again, is executed;
③
after the tool
infeed ( Δ d+e) is executed again, the end point of tool traversing reaches B’ point or
exceeds the straight line between A’ → B’ point and Z executes the tool infeed to B’
point, and then the next step is executed;
⑦
⑦ Cutting feed from B’ to C’ point along the roughing path;
⑧
Rapidly traverse to A from C’ point and the program jumps to the next clock following
nf block after G71 cycle is completed.