Temperature responsive, pressure operated diaphragm valve assembly for automobile engine

Claim 1

A temperature responsive, pressure operated diaphragm valve assembly for use in association with an automobile internal combustion engine having an intake duct leading to at least one combustion chamber, said intake duct having a throttle valve disposed therein for pivotal movement between a substantially closed position and a full open position, and an exhaust manifold leading from the combustion chamber towards the atmosphere, said temperature responsive, pressure operated diaphragm valve assembly comprising, in combination: a first valve actuator housing; a first diaphragm member housed within the first valve actuator housing and dividing the interior of the first valve actuator housing into a first chamber, and a second chamber communicated to the atmosphere; a first passage means between said first chamber and a portion of the intake duct; a first biasing spring housed within the first chamber and exerting a biasing force on the first diaphragm member to displace the latter in one direction; a first valving element carried by the first diaphragm member and positioned on one side of the first diaphragm member opposite to the first biasing spring, second passage means having one end communicated to the intake duct and the other end communicated to a source of fluid medium, said first valving element being movable by said first diaphragm member for selectively opening and closing said second passage means when and so long as the first diaphragm member is displaced in said one direction and opening said second passage when the first diaphragm member is displaced in the other direction opposite to said one direction; and means operable in response to change in an engine reference temperature for adjusting the biasing force of the first biasing spring according to a change in the engine reference temperature and including a first temperature sensing element having a parameter, the magnitude of said parameter being variable as a function of the engine reference temperature, and a first push rod supported for axial movement between projected and retracted positions and having one end connected to the first biasing spring and the other end operatively associated with the first temperature sensing element for, as the temperature sensed by the first temperature sensor increases, moving said first push rod from the retracted position towards the projected position adjusting the first biasing spring to change the biasing force thereof.