13. Program Support Functions
13.1 Fixed Cycles
270
(iii) Pecking tapping cycle
The load applied to the tool can be reduced by designating the depth of cut per pass (Q)
and cutting the workpiece to the hole bottom for a multiple number of passes.
The amount retracted from the hole bottom is set to the parameter "#8018 G84/G74
return".
Select either the pecking tapping cycle or the deep-hole tapping cycle by parameter.
("#1272 ext08/bit4")
When "depth of cut per pass Q" is designated in the block containing the G84 or G74
command in the state where the pecking tapping cycle is selected, the pecking tapping
cycle is executed.
In the following cases, the normal tapping cycle is established.
• When Q is not designated
• When the command value of Q is zero
G84 Xx1 Yy1 Zz1 Rr1 Qq1 Ff1 Ee1 Pp1 Ss1 ,Ss2 ,Ii1 ,Jj1 ,Rr2 ;
X, Yy
Z
R
Q
F
E
P
S
, S
, I
, J
, R
: Hole drilling position
: Hole bottom position
: Point R position
: Depth of cut per pass (designated as an incremental position)
: Z-axis feed amount (tapping pitch) per spindle rotation
: Tap thread number per 1-inch feed of Z axis
: Dwell time at hole bottom position
: Rotation speed of spindle
: Rotation speed of spindle during retract
: In-position width of positioning axis
: In-position width of hole drilling axis
: Synchronization method selection (r2=1 synchronous, r2=0 asynchronous)
(Note)
When ",R0" is commanded, F address is regarded as cutting federate.
Refer to the section "Fixed cycle" for details.
q
1
m
m
q
1
q
1
r
1
z
1
x1, y1
(1)
(2)
(3)
(6)
(4)
(5)
(7)
(10)
(9)
(11)
(8)
(n7)
(n5) (n6)
(n5) (n6)
(n4)
(n4)
(n1)
(n2) (n3)
M98
mode
M99
mode
(1) G0 Xx1 Yy1 , Ii1
(2) G0 Zr1
(3) G1 Zq1 Ff1
(4) M4 (Spindle reverse rotation)
(5) G1 Z-m Ff1
(6) M3 (Spindle forward rotation)
(7) G1 Z(q1+m) Ff1
(8) M4 (Spindle reverse rotation)
(9) G1 Z-m Ff1
(10)
M3 (Spindle forward rotation)
(11)
G1 Z(q1+m) Ff1
:
:
(n1)
G1 Z(z1-q1*n) Ff1
(n2)
G4 Pp1
(n3)
M4 (Spindle reverse rotation)
(n4)
G1 Z-z1 Ff1 Ss2
(n5)
G4 Pp1
(n6)
M3 (Spindle forward rotation)
G98 mode G0 Z-r1 , Ij1
G99 mode No movement
(n7)
* 1. m: Parameter "#8018 G84/G74 return"
2. This program is for the G84 command. The spindle forward rotation (M3)
and reverse rotation (M4) are reversed with the G74 command.