Helical interpolation, 5 p a th cont ours—p o lar c oor dinat e s – HEIDENHAIN iTNC 530 (60642x-03) ISO programming User Manual

Page 235

Advertising
background image

HEIDENHAIN iTNC 530

235

6.5 P

a

th cont

ours—P

o

lar

c

oor

dinat

e

s

Helical interpolation

A helix is a combination of a circular movement in a main plane and a
linear movement perpendicular to this plane. You program the circular
path in a main plane.

A helix is programmed only in polar coordinates.

Application

Large-diameter internal and external threads

Lubrication grooves

Calculating the helix

To program a helix, you must enter the total angle through which the
tool is to move on the helix in incremental dimensions, and the total
height of the helix.

For calculating a helix that is to be cut in an upward direction, you need
the following data:

Shape of the helix

The table below illustrates in which way the shape of the helix is
determined by the work direction, direction of rotation and radius
compensation.

Y

X

Z

CC

Thread revolutions n

Thread revolutions + thread overrun at
thread beginning and end

Total height h

Thread pitch P times thread revolutions n

Incremental total
angle H

Number of revolutions times 360° + angle for
beginning of thread + angle for thread
overrun

Starting coordinate Z

Pitch P times (thread revolutions + thread
overrun at start of thread)

Internal thread

Work
direction

Direction of
rotation

Radius
comp.

Right-handed
Left-handed

Z+
Z+

G13
G12

G41
G42

Right-handed
Left-handed

Z–
Z–

G12

G13

G42
G41

External thread

Right-handed
Left-handed

Z+
Z+

G13
G12

G42
G41

Right-handed
Left-handed

Z–
Z–

G12

G13

G41
G42

Advertising