Abstract: In a throttle valve opening sensor including a substrate provided with a throttle valve opening detecting portion, a rotor adapted to be rotated in association with rotation of a throttle valve, a housing for rotatably supporting the rotor and incorporating the substrate, a packing mounted in the housing for sealing the substrate, and a contact mounted on the rotor and adapted to slide on the opening detecting portion; the improvement comprises a substrate pressing portion formed at the packing for inwardly pressing the substrate, an O-ring projecting portion formed at the packing on the outer peripheral side of the substrate pressing portion and tightly contacting with the housing, and a cover provided outside the packing for inwardly pressing the substrate pressing portion and the projecting portion of the packing.

Abstract: A throttle valve opening sensor for detecting an opening and a specific opening of a throttle valve, comprising a substrate having a partially sectoral printed pattern formed by an opening detecting portion and a specific opening detecting portion for the throttle valve, a rotor adapted to be rotated in association with rotation of the throttle valve, a housing for rotatably supporting the rotor and having a substrate receiving hole for receiving the substrate, a packing installed in the housing for sealing the substrate, a cover mounted on the outside of the packing for fixing the substrate through the packing to the housing, first and second contacts mounted on the rotor and adapted to slide on the opening detecting portion and the specific opening detecting portion, a plurality of terminals installed in the housing and connected to lead wires for power supply and signal output, and a plurality of conductive elastic members for electrically connecting the terminals to the opening detecting portion and the s