Patent ID: 6609501
Filing Date: 2003-08-26
Classification: F02D,F02M

Abstract:
A fuel pressure regulation system for use with an internal combustion engine, comprising:a fuel pressure control device having a fuel inlet for receiving fuel, a fuel outlet in fluid communication with said inlet, and a signal input for receiving a control signal, said fuel pressure control device being operable in response to said control signal to provide fuel to said outlet at a downstream fuel pressure that is dependent on said control signal, a pressure switch for sensing the downstream fuel pressure and having a signal output for providing a switch state signal, wherein said switch state signal is in a first state when the downstream fuel pressure is below a reference pressure and is in a second state when the downstream fuel pressure is above the reference pressure, a current sensor for sensing the electric current used by said fuel pressure control device as a result of being operated by said control signal, said current sensor being operable to provide a current signal representative of the magnitude of that electric current, and a control circuit having a first signal input connected to said pressure switch signal output to receive said switch state signal, a second signal input connected to said current sensor to receive said current signal, and a signal output connected to said fuel pressure control device signal input to provide said control signal, wherein, when said switch state signal is in said first state, said control circuit adjusts said control signal so as to operate said fuel pressure control device in a manner that increases the downstream fuel pressure until it reaches said reference pressure, and wherein, when said switch state signal is in said second state, said control circuit adjusts said control signal in accordance with the current signal so as to operate said fuel pressure control device using closed loop control of the electric current used by said control device.