# Fanuc Series 15i/150i-MA (Programming) Operators Manual

B-63324EN/03 PROGRAMMING 19.AXIS CONTROL FUNCTIONS
- 727 -
helical gear compensation is applied with the synchronizing factor
remaining unchanged. Thus, a helical gear and spur gear can be
machined in succession.
NOTE
While synchronization specified by the method
compatible with hobbing machine is in progress, feed
per revolution is performed according to the rotation
speed about the slave axis of synchronization.
- End of synchronization
The synchronization of all synchronized axes is canceled. The absolute
coordinates of slave axis are updated according to the amount of
synchronous movement. For a rotation axis, the amount of synchronous
movement (modulus with respect to 360 degrees) is added to the
absolute coordinates. In a G80 block, no address other than O or N can
be specified.
- Compensation for helical gears
For a helical gear, a compensation movement along the C-axis is made
with respect to movement along the Z-axis according to the helix angle
of the gear.
Helical gear offset is executed according the next formula.
input) metric(for 360
QT
sin(P)Z
angleon Compensati ×
××
×
=
input)inch (for 360
T
sin(P)QZ
angleon Compensati ×
×
××
=
Compensation angle : Absolute value (degrees) with a sign
Z : Amount of Z-axis movement after G81 (mm or inch).
All movements along the Z-axis including automatic and
manual movements.
P : Gear helix angle (plus or minus value in degrees)
π : Ratio of the circumference of a circle to its diameter
T : Number of teeth
Q : Module (mm) or diametral pitch (1/inch)
The values of P, T, and Q are those specified in a G81 block.
NOTE
The axial feed axis is an axis along the central axis of
rotation about the C-axis and is usually the Z-axis.
For convenience, this manual uses the Z-axis.
When specifying an axis other than the Z-axis as the
axial feed axis, specify the axis number in parameter
5994.