INTEGRAL MANIFOLD ABSOLUTE PRESSURE AND AMBIENT ABSOLUTE PRESSURE SENSOR AND ASSOCIATED ELECTRONICS

摘要

Abstract of the Disclosure under Rule 72(b)A combination manifold absolute pressure and ambient absolutepressure sensor utilizing a single absolute pressure sensor and asecond sensor which is devised to sense the difference between themanifold pressure and atmospheric pressure. The second sensor isprovided with a switch mechanism actuated by a diaphram at a preselectedpressure difference between manifold pressure and atmospheric pressure.The actuation of the switch mechanism causes a sample-and hold circuitto sense the instantaneous manifold absolute pressure at the time ofactuation of the switch and electrically add the sensed manifold pressureto the set difference between the manifold pressure and atmosphericpressure to provide a signal indicative of ambient absolute pressure.This signal is utilized to provide altitude compensation in a fuelinjection system.