BBP Series of Air-Extended, Spring-Loaded LVDT Linear Position Sensors

The Macro Sensors BBP and BBT family of pencil-type gaging probes offers ultra-precise measurement of dimensions in a wide variety of Q.C., SPC, and industrial metrology applications. They utilize a linear ball bearing assembly precisely fitted to a hardened-and-ground, non-rotating probe shaft to minimize radial play and the effects of side loading. This results in the probes' exceptional repeatability of 0.000006 inch (0.15 ?m).

One end of the probe shaft is coupled to the core of a friction-free LVDT sensor, which produces an output voltage is linearly proportional to the probe shaft position. The use of an LVDT for probe shaft displacement sensing eliminates any additional transducer errors due to friction, stiction, or mechanical hysteresis. The output from the LVDT can be connected to any standard LVDT signal conditioner and then passed to a gaging column display, digital readout, or computer based data acquisition system.

The other end of the shaft is internally threaded to accept an interchangeable tungsten carbide contact tip for wear resistance and reliability. For normal applications, the probe shaft is fully extended by a spring exerting a force of about 2.5 ounces (70 grams) at the probe's mechanical zero position. The entire bearing, shaft, and LVDT assembly are enclosed in a stainless steel tubular housing.