Rapid growth of electronic controls in the automotive application field has increased the need for position sensors with longer life and higher accuracy. Non-contact (optic and magnetic) type position sensors offer advantages in durability, but lack in required output accuracy.
Contact type position sensors can offer advantages such as more temperature stability, higher resolution and EMI resistance, and a lower cost.
Traditionally, contact type position sensors are able to offer high output accuracy in initial condition. However, their performance degrades over life. This degradation is attributed primarily to abrasion between the resistive element and the contact brush. We have solved this problem by developing an improved resistive element.
This development materialized through the selection of a resistive element material that has excellent durability against brush contact abrasion.1)
Recently though, engines electronic throttle control type have been increasing in automobiles.
Along with this change, position sensors must achieve not only excellent durability but also better output accuracy.
We succeeded in developing a new resistive element which is called “KCP” (Komatsu conductive plastics), compatible with durability and high output accuracy. This paper will report in detail about the development of KCP.