The design of miniaturised displacement transducers for deep hole diameter measurement
The paper presents a new approach to the design of a miniaturised displacement transducer for deep hole measurement. By exploiting the induced eddy current effects detected by chip coils, the sensor generates a frequency output signal. The sensor chip coil can be manufactured by the similar processes to those used for manufacturing a printed circuit board (PCB) which allows them to be miniaturised. The paper elaborates on the construction and mechanism by which the displacement is directly transferred to a frequency output. It also reports on the transducer, which uses two contact probes for transmitting the displacement to a non-contact sensing element. Experimental results demonstrate the stability, linearity, measurement range and accuracy of the sensor system. (C) 1999 Elsevier Science Ltd. All rights reserved.
deep hole measurement eddy current chip coils frequency output displacement sensor