GSK GSK980TDc, Руководство пользователя

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Chapter 3 G Commands
119
Ⅰ
Progra
mming
G00 X25 Z2 ； //position to the thread starting point （ supposing the shape has been made at
the last tool
）
M14
；
//switch the spindle from speed control mode to position control mode
（
it is 0
。
position after switch
）
G50 C0
；
// set the zero of the rotary axis(it is important to set it because the operation is
relevant to the start angle of the following thread turning ）
G32.1 Z-20 F2 S500 M08
；
//thread turning; the speeds of the spindle and the feed axis are0 in
end point
G00 X30
；
//tool retraction
X24.5 Z2 C0 ； //return to thread starting point, and prepare for repetitively machining
G32.1 Z-20 F2 S500
；
// repetitively machine
． ． ． ． ； //repetitively machine
G00 X100
；
//tool retraction
Z100
；
//return to tool change position
M15
；
//switch the spindle from position control mode to speed control mode
． ． ． ． ； //execution the 2
nd
machining procedure
． ． ． ． ；
M30
；
//end of program
3.21.3 Thread cutting with variable lead G34
Command format
：
G34 X(U)__ Z(W)__ F(I)__ J__ K__ R__
；
Command function: The motion path of tool is a straight line from starting point of X, Z to end
point specified by the block, the longer moving distance from starting point
to end point(X in radius value) is called as the long axis and another is
called as the short axis. In course of motion, the long axis traverses one
lead when the spindle rotates one rev, the pitch increases or decreases a
specified value per rev and one spiral grooving with variable lead on the
surface of workpiece to realize thread cutting with variable lead. Tool
retraction can be set in thread cutting.
F, I are specified separately to metric, inch pitch. Executing G34 can machine metric or inch
straight, taper, end face thread with variable pitch.
Command specifications:
G34 is modal;
Meanings of X(U) , Z(W) , J, K are the same that of G32;
F: Specify lead, and its range is referred to Table 1-2;
I: Specify thread teeth per inch, and its range is referred to Table 1-2;
R: Increment or decrement of pitch per rev, R=F1- F2, with direction; F1>F2, pitch decreases
when R is negative; F1<F2, pitch increases when R is positive (as Fig. 3-41);
R: ±0.001~±500.000 mm/pitch (metric thread);
±0.060~±25400 tooth/inch (inch thread).
The system alarms when R exceeds the above-mentioned range or the pitch exceeds
permissive value or is negative owing to R increases or decreases.