GSK GSK988TA, Руководство пользователя

Страница: 175 / 531

Chapter 2 G Commands
157
Ⅰ
Programming
setting or max. spindle speed setting
G90 G77 Axial cutting cycle
G92 G78 Thread cutting cycle
G94 G79
01
Radial cutting cycle
Mode
*G98 *G94 Feed per minute
G99 G95
05
Feed per rotation
Mode
— *G90 Absolute code
— G91
03
Incremental code
Mode
— *G98 Fixed cycle return to initial plane
— G99
11
Fixed cycle return to point R plane
Mode
2.29.2 Absolute Code and Incremental Code G90, G91
Command function: G90 and G91 determine to use the absolute code or incremental code. G90
is an absolute code and G91 is an incremental code.
Command format:
Absolute code ： G90 IP_;
Absolute code
：
G91 IP_;
Command explanation: main differences between A set of G code system and A set of G code
system are to use the incremental code and absolute code. The A set of G code
system using U, V, W and H separately means X, Y, Z, C’s incremental code, but B
set of G code system using G90/G91 means the currently used incremental value or
absolute code value.
Example:
In A system, block
：
G01 X100 W100
In B system, block
：
G90 G01 X100
G91 Z100
2.29.3 Cycle Code Processing
In B set of G code system, U, W set in G71~G76 blocks are taken as a parameter set by a cycle
code to use, and is not taken as a axis movement code, even if U,W is set to a parallel axis.
The position code set in the cycle code is only specified by a corresponding axis code, and using
G90/G91 means the current programmed position is set by an absolute vaue or incremental value.
2.29.4 Drilling Fixed Cycle’s Return Operation G98, G99
In A set of G code system, the tool returns to the initial plane from the hole bottom. In B or C set
of G code, specifying G98 can make the tool return to the initial plane from the hole bottom and
specifying G99 can make the tool return to point R plane from the hole bottom. The following figure
specifies G98, G99 operations. Generally, the initial drilling uses G99 and the last uses G98.