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Accessories
Air-Bearing C-LVDT: Capacitive LVDT-Type Contact Sensor
The Air-Bearing C-LVDT converts a capacitive sensor using a standard capacitive probe into a high-precision contact
displacement sensor similar to an LVDT. The capacitive probe is installed in the top of the C-LVDT body where it measures
the location of a target connected on the inside end of the stylus. The C-LVDT uses a linear air-bearing for nearly friction-
free movement of the stylus, and the porous carbon air bearing is square to prevent stylus rotation. Adjustable air pressure for
extending the stylus provides for contact forces less than one gram, and the C-LVDT features a retraction port through which
application of air pressure will retract the stylus.
The C-LVDT uses an interchangeable diamond tip. Diamond has been selected over ruby for the following reasons:
●
Low Friction - Side forces cause less lateral deflection from moving targets and less hysteresis on direction reversal.
●
Highly Polished Surface - Diamond accepts and holds a high polish, minimizing the possibility of scratching the
measured surface.
●
Minimal Wear - Increased accuracy and longer life.
Contact Force Adjustment
There is a contact force adjustment screw located on the end of the probe body near the cable exit. Use a 1/16" hex key to
turn the adjustment clockwise to increase the contact force or counter clockwise to decrease it. Contact force is also a
function of the air pressure applied to the C-LVDT. To maintain constant contact force, supplied air pressure must be held
constant.
Air Exhaust
The 0.1" slot around the body near the top of the C-LVDT is where air is exhausted. Do not clamp the C-LVDT over this
ring. The ring must remain at least partially clear at all times for proper operation of the C-LVDT.
Specifications
Measurement Range
0.5 mm, 0.020 inch
Contact Force
0.2 g to 100 g
Radial Stiffness
< 0.25 µm/g
Bearing
Linear, porous air bearing
Diamond Tip
Radius: 3.175 mm, 0.125 inch
Mount: 4-48AGD Thread
Weight of Moving Mass
4.2 g
Air Connection
1/16 inch ID flexible tubing
Air Consumption
3-7 lpm, 0.10-0.25 cfm
Operating Air Pressure
420-480 kPa, 60-70 psi
Air Requirement
Dry, filtered to less than 5 µm particle size
Содержание CPL190
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