
13. Program Support Functions
13.1 Fixed Cycles
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Detailed description
(1) Outline of data and corresponding addresses
(a) Hole machining mode: Canned cycle modes such as drilling, counter boring, tapping and
boring.
(b) Hole position data: Data used to position the X and Y axes. (Unmodal)
(c) Hole machining data: Actual machining data used for machining. (Modal)
(d) Number of repetitions: Number of times to carry out hole machining. (Unmodal)
(e) Synchronization changeover: Synchronous/asynchronous tapping selection command is
issued during G84/G74 tapping. (Modal)
(2) If M00 or M01 is commanded in the same block as the canned cycle or during the canned cycle
mode, the canned cycle will be ignored. Instead, M00 and M01 will be output after positioning.
The canned cycle will be executed if X, Y, Z or R is commanded.
(3) There are 7 actual operations which are each described in turn below.
Operation 1
R point
Initial point
Operation 2
Operation 3
Operation 4
Operation 5
Operation 6
Operation 7
Operation 1 : This indicates the X and Y axes positioning, and executes positioning with G00.
Operation 2 : This is an operation done after positioning is completed (at the initial hole), and
when G87 is commanded, the M10 command is output from the control unit to
the machine. When this M command is executed and the finish signal (FIN) is
received by the control unit, the next operation will start. If the single block stop
switch is ON, the block will stop after positioning.
Operation 3 : The tool is positioned to the R point by rapid traverse.
Operation 4 : Hole machining is conducted by cutting feed.
Operation 5 : This operation takes place at the hole bottom position and it differs according to
the canned cycle mode. Possible actions include spindle stop (M05) spindle
reverse rotation (M04), spindle forward rotation (M03), dwell and tool shift.
Operation 6 : The tool is retracted to the R point.
Operation 7 : The tool is returned to the initial pint at the rapid traverse rate.
Whether the canned cycle is to be completed at operation 6 or 7 can be selected by the
following G commands.
G98 ............ Initial level return
G99 ............ R point level return
These are modal commands, and for example, if G98 is commanded once, the G98 mode will
be entered until G99 is designated. The initial state when the NC is ready is the G98 mode.
The hole machining data will be ignored if X, Y, Z or R is not commanded. This function is
mainly used with the special canned cycled.