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Laser Maintenance and Trouble Shooting |
Topics:
10 W CO2 Laser
Workstation
Laser Tube
Vacuum System
Gas Flow System
Laser Resonator
High Voltage Supply
X-Y Translation Stage
Computer Control |
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Principle of operation
Lasers and especially workstations are complex systems and
malfunctions cannot be excluded. Furthermore, a laser system has
to be maintained since some parts of it have a limited life as
“for example” the discharge lamps for the Nd:YAG Laser, oil of
the vacuum pump for the CO2 Laser and so on.
The goal of this workshop is the training for maintenance and
trouble shooting performed with a modified CO2 Experimental
Laser workstation. The workstation is prepared in such a way
that the trainer is enabled to prepare several malfunctions. The
entire laser system can be structured in the following sub
systems:
1. Laser tube
2. Laser resonator
3. Gas flow system
4. High voltage supply
5. X-Y translation stage
6. Computer control
7. Safety interlock System
The laser head is designed as an open frame resonator where all
components can be seen through a translucent cover. The laser
mirror of the optical resonator can be aligned by means of fine
pitch screws for best performance.
The top and the door of the laser workstation are made out of a
translucent cover which absorbs the generated laser radiation.
Therefore, the material processing can be observed without
danger to the human eye or skin. The laser can only be activated
when a variety of safety interlocks are closed. Opening the door
of the work station shuts down the operation immediately, so
that the entire laser system is classified as Class 1 Laser.
The electronics cabinet contains the high voltage supply for the
CO2 Laser and a closed loop water cooling system. A vacuum pump
is used to control the proper pressure and gas flow inside the
discharge tube and a suction pump removes fumes and residue of
the material processing.
In the manual, a flow chart is given which shows the network or
interaction of these systems. Possible malfunctions are listed
and with yes/no branches, the error can be located. Such a list
is never complete and will therefore be extended during the
course by the students. As part of the system, faulty parts are
provided to generate the desired malfunction, for instance, if
the connection of an safety interlock switch is removed, the
laser system cannot be started. This can be caused by a number
of other reasons. Another malfunction can be the low power
output of the laser which can be simulated by using one or two
of the faulty laser mirrors or by the focusing lens. A broken
washer prevents the vacuum system from reaching the required
pressure inside the tube. Another class of malfunctions can
occur in the workstation section due to a broken PC controller
I/O card, broken connection cables or clutch of the motor drive.
All these and a lot more malfunctions can be simulated within
the system making the students experts also for other laser
systems a method of analysing a malfunction will be the same for
all. |
Required Equipment
| Cat. No. |
Qty. |
Description |
Illustration |
09.0090 |
1 |
EXP 09 CO2 laser 10W with workstation
This control unit contains the stepper motor controller
and computer interface to be used in connection with the
laser workstations. Beside an emergency stop, the front
panel is also provided with a master key controlled
input to manually operate the laser
|
No
illustration |
09.0232 |
1 |
Set of faulty laser mirror
Two laser mirrors, one output coupler and one fully
reflective, are prepared with scratches to reduce the
output power significantly.
|
No
illustration |
09.0233 |
1 |
Faulty beam shutter
The beam shutter is closed also in the on position.
|
No
illustration |
09.0234 |
1 |
Faulty focusing lens
The focusing lens is provided with several severe
scratches which reduces the output power and distorts
the beam.
|
No
illustration |
09.0235 |
1 |
Set of faulty connection cable
The connection cables are manipulated in such a way that
some connection are not made.
|
No
illustration |
09.0236 |
1 |
Set of misc. faulty parts
A collection of broken fuses, washers, clutches for the
translation stage, faulty remote control push button.
|
No
illustration |
09.0237 |
1 |
Faulty I/O board for PC-controller
This board serves as a driver for the X-Y translation
stages and is prepared in such a way that one of the
motors cannot be driven.
|
No
illustration |
10.0230
|
1 |
EXP 23 manual |
No
illustration |
Required Options
|
19.0500 |
1 |
Laser gas bottle, 13.5 vol% N2, 4.5 vol% CO2, 82 vol% He
200 Bar
For the operation of the slow flow 10 Watt CO2 laser a
gas mixture with the following composition is required:
Nitrogen N2: 13.5 vol. %
Carbon Dioxide CO2: 4.5 vol. %
Helium He: 82.0 vol. %
The gas bottle is filled at a pressure of 200 Bar
requiring a pressure reducer for the laser operation at
3-5 Bar.
|
No
illustration |
19.0502 |
1 |
Pressure reducer 200/3-5 Bar
To provide the CO2 laser with its gas mixture a pressure
of 3-5 Bar is needed. Since the gas bottles come with a
pressure of 200 Bar, this reducer is needed to adjust
the optimum pressure conditions for the laser operation.
|
No
illustration |
19.1000 |
1 |
IBM compatible PC, incl. VGA monitor and keyboard
For some experiments a PC is a must whereas others can
operate without one. However, some nice features may be
not accessible. Due to the steadily changing models and
operating systems a picture is not given. Please ask for
current models.
|
No
illustration |
Options
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09.0189
|
1 |
Set of spare parts |
No
illustration |
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