Patent ID: 6035837
Filing Date: 2000-03-14
Classification: F02D,Y02T

Abstract:
A bi-fuel, variable vapor pressure injection system for an internal combustion engine, comprising:a source of first liquid fuel;a source of second liquid fuel;at least one variable vapor pressure fuel injector;a common fuel rail for supplying one of said first and second fuels to said at least one fuel injector;a first valve structure in selective communication with each of said sources of said first and second fuels and in communication with an inlet of said fuel rail to selectively control supply of one of said first and second fuels to said fuel rail; anda second valve structure in communication with an outlet of said fuel rail and in selective communication with said source of second fuel to return fuel exiting said fuel rail to said source of second fuel, said second valve structure being in selective communication with a vapor purge system to receive fuel vapors exiting said fuel rail,said first and second valve structures being selectively controllable (1) to permit residual first fuel to be purged from said fuel rail into said source of second fuel when supplying said second fuel to said fuel rail, and (2) to permit residual second fuel to be purged from said fuel rail into said vapor purge system when supplying said first fuel to said fuel rail.