Mitsubishi Electric MELDAS C6 Programming Manual page 168

13. Program Support Functions
(g) G87 (Back boring)
Program
G87 Xx
(Note) Take care to the z
The operation stops at after the (1), (4), (6) and (11) commands during single block
operation.
When this command is used, high precision drilling machining that does not scratch the
machining surface can be done.
(Positioning to the hole bottom and the escape (return) after cutting is executed in the
state shifted to the direction opposite of the cutter.)
The shift amount is designated as shown below with addresses I, J and K.
Spindle orient
position
The shift amount is executed with linear interpolation, and the feed rate follows the F
command.
Command I, J, and K with incremental values in the same block as the hole position data.
I, J and K will be handled as modals during the canned cycle.
(Note)
Yy Zz Rr Iq Jq
1 1 1 1 1 2
and r
1
(The z and r symbols are reversed).
1 1
There is no R point return.
x , y
(3)
1 1
(1)
(12)(11)
(2)
(8) (9)
(7)
(6) (5)
Tool during cutting
Cutter
Cancel
Cancel
Shift
Shift amount
If the parameter "#1080 Dril_Z" which fixes the hole drilling axis to the Z axis is
set, the shift amount can be designated with address Q instead of I and j. In this
case, whether to shift or not and the shift direction are set with parameter
"#8207 G76/87 IGNR" and "#8208 G76/87 ( − )". The symbol for the Q value is
ignored and the value is handled as a positive value.
The Q value is a modal during the canned cycle, and will also be used as the
G83, G73 and G76 cutting amount.
160
Ff ;
1
designations.
1
(1) G0 Xx
Xq (Yq )
(2) M19 (Spindle orient)
1 2
(3) G0 Xq
(4) G0 Zr
(10)
(5) G1 X−q
r
1
(6) M3 (Spindle forward rotation)
(7) G1 Zz
(4)
(8) M19 (Spindle orient)
(9) G0 Xq
G98 mode
z
1
(10)
G99 mode
(11) G0 X−q
(12) M3 (Spindle forward rotation)
Tool after cutting
Shift
Machining hole
13.1 Canned cycles
Yy
1 1
(Yq ) (Shift)
1 2
1
(Y−q ) Ff (Shift)
1 2 1
Ff
1 1
(Yq ) (Shift)
1 2
G0Z − (z
+r )
1 1
G0Z − (r
+z )
1 1
(Y−q ) (Shift)
1 2
For G17 : I, J
For G18 : K, I
For G19 : J, K