摘要 |
In a common rail gasoline fuel injection system having a high pressure fuel supply pump (14) in which fuel is pressurized in a pumping chamber and delivered through a high pressure passage (16) to the common rail (18), the improvement comprising a flow volume intensifier (22) situated in the high pressure passage (16). Preferably the intensifier has a cranking configuration in which a primary piston (32) of relatively low effective cross sectional area on which only the primary pressure of the pumping chamber is imposed, and a secondary piston (44) contacting the primary piston (32) and having a relatively large effective cross sectional area on which only the common rail pressure is imposed, whereby when the primary piston (32) is displaced a primary volume toward the secondary piston (44) by the primary pressure from the pumping chamber, the secondary piston (44) displaces a secondary volume of fuel into common rail (18) that is larger said primary volume.
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