GSK GSK980TDc, Руководство пользователя

Страница: 133 / 470

Chapter 3 G Commands
115
Ⅰ
Progra
mming
to start machine after the system receives spindle signal per rev in thread cutting, and so one thread
is machined by multiple roughing, finishing without changing spindle speed.
The system can machine many kinds of thread cutting, such as thread cutting without tool
retraction groove. There is a big error in the thread pitch because there are the acceleration and the
deceleration at the starting and ending of X and Z thread cutting, and so there is length of thread
lead-in and distance of tool retraction at the actual starting and ending of thread cutting.
X, Z traverse speeds are defined by spindle speed instead of cutting feedrate override in thread
cutting when the pitch is defined. The spindle override control is valid in thread cutting. When the
spindle speed is changed, there is error in pitch caused by X and Z acceleration/deceleration, and so
the spindle speed cannot be changed and the spindle cannot be stopped in thread cutting, which will
cause tool and workpiece to be damaged.
3.21.1 Thread cutting with constant lead G32
Command format: G32 X(U)_ Z(W)_ F(I)_ J_ K_ Q_
Command function: The path of tool traversing is a straight line from starting point to end point as
Fig.3-33; 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 revolution, and the short axis and
the long axis execute the linear interpolation. Form one spiral grooving with variable lead
on the surface of workpiece to realize thread cutting with constant lead. Metric pitch and
inch pitch are defined respectively by F, I. Metric or inch straight, taper, end face thread
and continuous multi-section thread can by machined in G32.
Command specifications:
G32 is modal;
Pitch is defined to moving distance when the spindle rotates one rev(X in radius);
Execute the straight thread cutting when X coordinates of starting point and end point are the
same one(not input X or U);
Execute the end face thread cutting when X coordinates of starting point and end point are the
same one(not input Z or W);
Execute the cutting taper thread when X and Z coordinates of starting point and end point are
different;
Related definitions:
F: Metric pitch is moving distance of long axis when the spindle rotates one rev: 0.001 mm ～ 500
mm. After F is executed, it is valid until F with specified pitch is executed again.
I: Teeth per inch. It is ones per inch(25.4 mm) in long axis, and also is circles of spindle rotation
when the long axis traverses one inch(25.4 mm) :0.06tooth/inch ～ 25400tooth/inch. After I is
executed, it is valid until I with specified pitch is executed again. The metric, inch input both
express the teeth per inch thread.
J: Movement in the short axis in thread run-out, its range: ±99999999× least input increment with
negative sign; if the short axis is X, its value is specified with the radius; J value is the modal
parameter.
K: Length in the long axis in thread run-out, its range: ±99999999× least input increment. If the
long axis is X, its value is in radius without direction; K is modal parameter.
Q: Initial angle(offset angle)between spindle rotation one rev and starting point of thread cutting:
0
～
360000 (unit: 0.001 degree). Q is non-modal parameter, must be defined every time,
otherwise it is 0
0
.