1. Field of the Preferred Embodiment(s)
This invention generally relates to position sensing and to a position sensor which is compact, durable and precise. More specifically, the invention relates to an exhaust gas recirculation valve sensor.
2. Description of the Related Art
Position sensing is used to allow an electrical circuit to gain information about an event or a continuously varying condition. There are a variety of known techniques for position sensing. For example, optical, electrical, electrostatic, and magnetic fields are all used in a sensor to measure position. There are many known sensors such as resistive contacting networks, inductively coupled ratio sensors, variable reluctance devices, capacitively coupled ratio detectors, optical detectors using the Faraday effect, photo-activated ratio detectors, and electrostatic ratio detectors.
There are many applications for sensors, and a wide variety of technologies to fill these needs. Each of these technologies offers a unique set of advantages and limitations. Of these applications, exhaust gas recirculation (EGR) valve sensing, is known to have its own unique requirements. An EGR valve sensor must be compact and rugged to resist the severe vibration, temperature and chemical exposure when mounted on an internal combustion engine.