HEIDENHAIN TNC 620 (340 56x-01) - Manual (Page 148)

148
6.2 F
undamentals of P
a
th F
unctions
Circles and circular arcs
The TNC moves two axes simultaneously on a circular path relative to
the workpiece. You can define a circular movement by entering the
circle center CC.
When you program a circle, the control assigns it to one of the main
planes. This plane is defined automatically when you set the spindle
axis during a TOOL CALL:
Direction of rotation DR for circular movements
If a circular path has no tangential transition to another
contour element, enter the direction of rotation DR:
Clockwise direction of rotation: DR–
Counterclockwise direction of rotation: DR+
Radius compensation
The radius compensation must be in the block in which you move to
the first contour element. You cannot begin radius compensation in a
circle block. It must be activated beforehand in a straight-line block
(see “Path Contours—Cartesian Coordinates,” page 158) or approach
block (APPR block, see “Contour Approach and Departure,” page
150).
Pre-positioning
Before running a part program, always pre-position the tool to prevent
the possibility of damaging it or the workpiece.
X
Y
X
Y
CC
X
CC
Y
CC
Spindle axis Main plane
Z XY, also
UV, XV, UY
Y ZX, also
WU, ZU, WX
X YZ, also
VW, YW, VZ
You can program circles that do not lie parallel to a main
plane by using the function for tilting the working plane
(see “WORKING PLANE (Cycle 19, software option 1),”
page 355) or Q parameters (see “Principle and
Overview,” page 386).
CC
CC DR–
DR+
X
Z
Y