Altitude compensating apparatus for use with an internal combustion engine

Claim 1

An altitude compensating apparatus for use with an internal combustion engine comprising: a housing having a first and a second air passage formed therein; a cover secured to said housing for forming with said housing an atmosphere chamber to be supplied with the atmosphere; a block secured to said housing; a deflectable diaphragm interposed between said housing and said block for forming a pressure chamber with said housing and a sub-atmosphere chamber with said housing and a sub-atmosphere chamber with said block; said pressure chamber and said sub-atmosphere chamber communicating with said atmosphere chamber through said first air passage and said second air passage respectively; a pressure inlet and a pressure outlet both formed on said housing and communicating with said pressure chamber; said pressure inlet and outlet being adapted for connection to an intake manifold and a vacuum advancer of a distributor of an engine, respectively; at least one air outlet formed on said block and communicating with said sub-atmosphere chamber; said air outlet being disposed for connection to an air bleed of a carburetor of the engine; said diaphragm having a valve portion normally closing said air outlet; said valve portion being disposed to open said air outlet with the deflection of said diaphragm when the negative pressure is transmitted in said pressure chamber and acts on said diaphragm; at least one bellows disposed in said atmosphere chamber for forming therein a chamber to be confined with the air or gas at a predetermined pressure; said bellows being of the type that expands as the atmospheric pressure decreases; and a valve connected to said bellows for normally opening said first air passage; said valve being disposed to close said first air passage by the expansion of said bellows.