PROGRAMMING7. COORDINATE SYSTEM
The point that is specific to a machine and serves as the reference of the
machine is referred to as the machine zero point. A machine tool builder
sets a machine zero point for each machine.
A coordinate system with a machine zero point set as its origin is referred
to as a machine coordinate system.
A machine coordinate system is set by performing manual reference
position return after power–on (see III–3.1). A machine coordinate
system, once set, remains unchanged until the power is turned off.
G53 _ ;
_ : Absolute dimension word
When a command is specified based on a machine coordinate system, the
tool moves by rapid traverse. G53, which is used to select a machine
coordinate system, is a one–shot G code; that is, it is valid only in the
block in which it is specified. The absolute command (G90) is valid. If
the incremental command (G91) is specified, G53 is not executed. When
the tool is to be moved to a machine–specific position such as a tool
change position, program the movement in a machine coordinate system
based on G53.
When the G53 command is specified, cancel the cutter compensation, and
Since the machine coordinate system must be set before the G53
command is specified, at least one manual reference position return or
automatic reference position return by the G28 command must be
performed after the power is turned on. This is not necessary when an
absolute–position detector is attached.
D Selecting a machine
coordinate system (G53)
D Cancel of the
D G53 specification