US 4,275,694 A · Electronic controlled fuel injection system

Abstract

An electronic controlled fuel injection system for use in an internal combustion engine is disclosed which comprises a Karman's vortex flow sensor for measuring the flow of air supplied to the engine to provide an intake air flow indicative signal, a flow deriving circuit responsive to throttle opening and engine speed measurements for deriving an intake air flow measurement to provide an intake air flow indicative signal, a control circuit for providing an injection pulse signal in synchronism with rotation of the engine, the injection pulse signal having its pulse width determined in accordance with the intake air flow measurement, and a signal selector responsive to engine operating condition for passing the intake air flow indicative signal from the Karman's vortex flow sensor to the control circuit when the engine is under low load conditions and for passing the intake air flow indicative signal from the flow deriving circuit to the control circuit when the engine is under high load conditions.

Claims5

Dependent claims

A fuel supply system for use in an internal combustion engine having an intake passage and a throttle valve therein, said system comprising:

(a) means for supplying a controlled amount of fuel to said engine in accordance with intake air flow rate;
(b) a Karman's vortex flow meter located in said intake passage upstream of said throttle valve for providing a first signal corresponding to the rate of air flow through said intake passage;
(c) means, responsive to engine rotational speed and throttle position, for providing a second signal corresponding to the rate of air flow through said intake passage;
and
(d) a signal selector means for connecting one of said signals to said fuel supply means, said selector means normally connecting said first signal to said fuel supply means, said selector means connecting said second signal to said fuel supply means when the engine load exceeds a predetermined value.

2 more elements

Dependencies are inferred from the claim text.

Electronic controlled fuel injection system

Life of this patent

Electronic controlled fuel injection system

Life of this patent

Abstract

Claims5