
B–70114EN/04
4. FUNCTIONS
95
Fig. 4.1.1 (a) to (g) show the internal structure of the laser oscillator.
The FANUC LASER C series consists of a laser resonator, laser excitation
power supply, forced gas circulating system, pressure controller, exhaust
controller, CNC interface, and a protective housing.
The laser resonator consists of several discharge tubes, connected in series
using folding mirrors, with a rear mirror and output mirror placed at the
open ends of the discharge tubes, thus sealing the tubes. The resonator
is fitted with a gas pipe connecting port through which laser gas is fed into
the discharge tubes.
A discharge from the electrodes of the discharge tube energizes CO
2
molecules, which emit light. This light is amplified by stimulated
emission, repeated between the rear mirror and output mirror, a laser beam
being emitted from the output mirror.
This is a 2–MHz high–frequency power supply, the output of which is
controlled by the CNC. This power supply is used to create a discharge
in the laser gas flowing through the discharge tubes, thus energizing CO
2
molecules.
A gas circulating system is configured by connecting the resonator and
turbo blower with a circulating pipe. Laser gas is forced through the
discharge tubes at a speed of 200 m/s or higher.
A water–cooled heat exchanger, used to cool the high–temperature gas
from the discharge tubes, is provided at the inlet side of the turbo blower.
At the outlet side of the turbo blower, another water–cooled heat
exchanger dissipates the compression heat.
The laser gas pressure within the forced gas circulating system is
controlled by commands issued from the CNC, thus ensuring stable laser
output.
The laser gas flow is controlled by commands issued from the CNC.
Interface used to connect a FANUC Series 0–L or 16–L. 16i–L CNC
commands that, control the operation of the laser oscillator, such as
start/stop and laser output, are input via this interface.
An enclosure that houses the above components. The housing, consisting
of metal panels and doors, completely encloses the laser oscillator, thus
protecting the operator from exposure to laser radiation and from high
voltages. All panels are screw–fixed and cannot be removed without an
appropriate tool. The doors are also designed to prevent an accident from
occurring as a result of careless operation. The doors can be opened only
when the main circuit breaker is open. A door interlock function is also
supported.
4.1
INTERNAL
STRUCTURE
4.1.1
Outline
Laser resonator
Laser excitation power
supply
Forced gas circulating
system
Pressure controller
Exhaust controller
CNC interface
Protective housing