Non-contact length and speed measuring for any material – not a problem for linear measurement sensors. That is because the non-contact OLV measurement system is an impressive, flexible alternative wherever slippage, vibrations, and wear cause tactile measuring wheels, measuring rollers, or tachometers to generate measurement errors and damage.
Linear measurement sensors’ principle of operation is based on laser-Doppler technology. This involves a striped pattern being generated on the measured object by two laser beams (1.). The movement of the object surface (3.) modulates the intensity of the light picked up by the detector (2.). The frequency of this modulation corresponds to the laser- Doppler frequency. The light picked up by the detector is transformed into a signal, which a digital signal processor (DSP) uses to calculate the speed and path length.
One of the benefits of laser-Doppler technology: You do not need to use any special markers on the measured object. Combined with the high level of ruggedness and simple operating concept, this means that the technology can be used in a wide array of applications:
Tire and rubber industry
The OLV product family can be used for velocity synchronization tasks, among other things, due to its accurate speed and length measurement. This makes it possible to achieve consistent material quality (e.g., profile thickness) and control cutting processes for tire production machinery (extruders).
The OLV sensor product family offers reliable speed measurement for manufacturing products such as steel rods, sheet steel, wire, or pipes – even on hot material surfaces up to 1100 °C.
Printing and paper industry
Length measurement (for example, for incoming goods and pre-delivery inspection) and velocity or differential speed measurement (using two sensors) belong to the OLV product family’s scope of application as well as slip detection and control of cutting and pressing processes.