Hydraulically-actuated system having a variable delivery fixed displacement pump

A hydraulically actuated system comprising:

• a fixed displacement pump with a plurality of parallel disposed pistons that reciprocate in a pump housing that defines a high pressure area and a low pressure area;
• a control valve attached to said housing and being moveable between a first position in which said pistons displace fluid in a first proportion between said high pressure area and said low pressure area, and a second position in which said pistons displace fluid in a second proportion between said high pressure area and said low pressure area, and said control valve including a plurality of sleeves surrounding different ones of said plurality of pistons, and said plurality of sleeves being moveable with respect to said pump housing by an actuator between said first position and said second position, and said actuator being stoppable at a plurality of positions between said first position and said second position;
• a high pressure rail connected to said high pressure area of said pump;
• a plurality of hydraulically actuated fuel injectors connected to said high pressure rail;
• a source of low pressure fluid connected to said low pressure area of said pump;
• an electronic control module in communication with and capable of controlling a position of said control valve;
• and
• a spring operably positioned to bias said control valve toward a position at which said pistons displace a majority of said fluid into said low pressure area.

A hydraulically actuated system comprising:

• a fixed displacement pump with a plurality of parallel disposed pistons that reciprocate in a pump housing that defines a high pressure area and a low pressure area;
• a control valve attached to said housing and being moveable between a first position in which said pistons displace fluid in a first proportion between said high pressure area and said low pressure area, and a second position in which said pistons displace fluid in a second proportion between said high pressure area and said low pressure area, and said control valve including a plurality of sleeves surrounding different ones of said plurality of pistons, and said plurality of sleeves being moveable with respect to said pump housing by an actuator between said first position and said second position, and said actuator being stoppable at a plurality of positions between said first position and said second position;
• a high pressure rail connected to said high pressure area of said pump;
• a plurality of hydraulically actuated fuel injectors connected to said high pressure rail;
• a source of low pressure fluid connected to said low pressure area of said pump;
• an electronic control module in communication with and capable of controlling a position of said control valve to stop at said plurality of positions;
• a rail pressure sensor connected to said high pressure rail and capable of communicating a pressure signal to said electronic control module;
• an engine operating condition sensor capable of communicating an operating condition signal to said electronic control module;
• and
• a spring operably positioned to bias said control valve toward a position at which said pistons displace a majority of said fluid into said low pressure area.