In the world of laser marking, How to disassemble and install the vibrating mirror of the laser marking machine？the “Vibrating Mirror” (Galvanometer or Galvo Head) is the precision heart of the machine. It contains two high-speed mirrors that direct the laser beam. Because these are sensitive optical and electronic components, you must handle them with extreme care.
Warning: Before starting, ensure the machine is powered off and unplugged. Avoid touching the mirror surfaces with your bare fingers, as skin oils can burn into the glass when the laser hits them.
Part 1: Disassembly Procedure
1. Preparation & Safety
- Wear powder-free nitrile gloves.
- Move the Z-axis (lifting column) to a comfortable height to give yourself room to work.
- Remove the Field Lens (F-theta lens): Carefully unscrew the large lens at the bottom of the galvo head. Place it in a protective bag or box immediately.
2. Disconnect Cables
- Locate the data cables (usually two DB15 or specialized multi-pin cables) connecting the galvo head to the control card.
- Unscrew the locking screws on the connectors and gently pull them out.
3. Mechanical Detachment
- The galvo head is typically held in place by four Hex (Allen) screws on the top or side of the mounting bracket.
- Support the galvo head with one hand while loosening the screws with the other to prevent it from dropping onto the worktable.
- Carefully slide the unit away from the laser source output (the fiber isolator or CO2 path).
Part 2: Installation Procedure
1. Aligning the Optical Path
- Check the “entry hole” of the galvo head. Ensure there is no dust on the internal mirrors. If there is, use a clean air bulb (not compressed air cans) to blow it out.
- Align the galvo head’s input aperture with the laser source’s output. Physical alignment is crucial: if the beam enters at an angle, your marking will be distorted or “clipped.”
2. Securing the Head
- Re-insert the four Hex screws. Tighten them in a diagonal pattern (like lug nuts on a car tire) to ensure even pressure and alignment.
- Do not overtighten yet; you may need to make slight adjustments once you test the red-light alignment.
3. Reconnecting and Lens Attachment
- Plug the data cables back in and tighten the connector screws.
- Carefully screw the Field Lens back onto the bottom of the galvo head. Ensure it is threaded correctly to avoid “cross-threading.”
Part 3: Post-Installation Calibration
Once installed, the machine’s “brain” needs to be synced with the new “eyes.” You will likely need to perform these steps in your software (e.g., EZCAD):
- Red Light Adjustment: Ensure the red light pointer is centered within the marking field.
- Field Size Calibration: Mark a $100 \times 100\text{ mm}$ square. If it measures $98\text{ mm}$, adjust the “Scale” or “Galvo Gain” in the software.
- Squareness (Trapezoid) Correction: If the square looks like a trapezoid, adjust the “Keystone” settings in the software.
- Focal Length Check: Since you moved the head, your focal height (the distance from the lens to the part) may have shifted slightly. Re-find your “sweet spot” where the spark is brightest.
Pro-Tips for Success
- Keep the dust cap on: If the laser source is exposed during disassembly, cover it with the original plastic cap to prevent dust from entering the fiber cable.
- Check the ground: Ensure the galvo housing is properly grounded to the machine frame to prevent “jitter” caused by static or electromagnetic interference.