Cyclic pressurization including plural pressurization units interconnected for energy storage and recovery

A fuel injection system for an internal combustion engine having multiple combustion chambers and a camshaft for cyclically imparting pressurization energy to, and recovering pressurization energy from, fuel supplied to the engine, comprising

• a. a source of fuel at low pressure;
• b. a first set of unit injectors mounted for injecting fuel at high pressure into the combustion chambers, respectively, of the internal combustion engine, each said unit injector including
• i. an injector body containing a bore for receiving fuel at low pressure from said source of fuel and an injection orifice in fluid communication periodically with said bore, and
• ii. a pressurizing plunger mounted for reciprocation within said bore to form a fuel pressurizing chamber from which fuel may be withdrawn at relatively high pressure for injection into a corresponding combustion chamber of the engine through said injection orifice;
• c. a camshaft linkage for simultaneously reciprocating the pressurizing plungers of a set of at least two unit injectors as the engine camshaft rotates to selectively impart pressurization energy to fuel trapped within said fuel pressurizing chambers when said pressurizing plungers advance and to recover pressurization energy from fuel trapped within said fuel pressurizing chambers when said pressurizing plungers retract;
• and
• d. a first interconnecting line for allowing fluidic interconnection of the fuel pressurizing chambers formed within said first set of unit injectors to allow fluidic linkage of the volume of fuel being simultaneously pressurized and depressurized within said interconnected fuel pressurizing chambers of said first set of unit injectors,
• (i) wherein the total volume of fuel that is fluidically linked together within said first set of synchronized unit injectors substantially exceeds the volume of fuel injected during each injection event to avoid substantial loss of injection pressure during each injection event,
• (ii) wherein said camshaft linkage is arranged for reciprocating synchronously the pressurizing plungers of a second set of at least two unit injectors as the engine camshaft rotates to selectively impart pressurization energy to fuel trapped within the corresponding fuel pressurizing chambers of said second set of unit injectors when the pressurizing plungers of said second set of unit injectors advance and to recover pressurization energy from fuel trapped within said fuel pressurizing chambers when said pressurizing plungers retract, and further including a second interconnecting line for allowing fluidic interconnection of the fuel pressurizing chambers of said second set of synchronized unit injectors to allow fluidic linkage of the volume of fuel being simultaneously pressurized and depressurized within said interconnected fuel pressurizing chambers of said second set of unit injectors, said second set of synchronized unit injectors being out of phase by a predetermined amount with respect to said first set, wherein the total volume of fuel that is fluidically linked together within said second set of synchronized unit injectors substantially exceeds the volume of fuel injected during each injection event to avoid substantial loss of injection pressure during each injection event, and
• (iii) wherein each said unit injector of said second set of unit injectors includes a nozzle control valve having a closed position for preventing the flow of fuel into the corresponding combustion chamber and an open position in which fuel from said fluidically connected fuel pressurizing chambers of said first set of unit injectors is allowed to flow into the corresponding combustion chamber through the corresponding injection orifice.

A fuel injection system for an internal combustion engine having multiple combustion chambers and a camshaft for cyclically imparting pressurization energy to, and recovering pressurization energy from, fuel supplied to the engine, comprising

• a. a source of fuel at low pressure;
• b. a first set of unit injectors mounted for injecting fuel at high pressure into the combustion chambers, respectively, of the internal combustion engine, each said unit injector including
• i. an injector body containing a bore for receiving fuel at low pressure from said source of fuel and an injection orifice in fluid communication periodically with said bore, and
• ii. a pressurizing plunger mounted for reciprocation within said bore to form a fuel pressurizing chamber from which fuel may be withdrawn at relatively high pressure for injection into a corresponding combustion chamber of the engine through said injection orifice;
• c. a camshaft linkage for simultaneously reciprocating the pressurizing plungers of a set of at least two unit injectors as the engine camshaft rotates to selectively impart pressurization energy to fuel trapped within said fuel pressurizing chambers when said pressurizing plungers advance and to recover pressurization energy from fuel trapped within said fuel pressurizing chambers when said pressurizing plungers retract;
• and
• d. a first interconnecting line for allowing fluidic interconnection of the fuel pressurizing chambers formed within said first set of unit injectors to allow fluidic linkage of the volume of fuel being simultaneously pressurized and depressurized within said interconnected fuel pressurizing chambers of said first set of unit injectors,
• wherein the total volume of fuel that is fluidically linked together within said first set of synchronized unit injectors substantially exceeds the volume of fuel injected during each injection event to avoid substantial loss of injection pressure during each injection event,
• wherein each said unit injector includes a pressure control valve connected to said source of fuel, each said pressure control valve having an open condition in which fuel is allowed to flow in either direction between said source of fuel and the corresponding fuel pressurizing chamber of said unit injector and a closed condition in which no fuel is allowed to flow between the corresponding fuel pressurizing chamber and said source of fuel.

A fuel injection system for an internal combustion engine having multiple combustion chambers, comprising

• a. a source of fuel at low pressure;
• b. a first set of injectors mounted for injecting fuel at high pressure into the combustion chambers, respectively, of the internal combustion engine, each said injector including
• i. an injector body containing a bore for receiving fuel at low pressure from said source of fuel and an injection orifice in fluid communication periodically with said bore, and
• ii. a pressurizing plunger mounted for reciprocation within said bore to form a fuel pressurizing chamber from which fuel may be withdrawn at relatively high pressure for injection into a corresponding combustion chamber of the engine through said injection orifice;
• c. actuating means for simultaneously reciprocating the pressurizing plungers of a set of at least two injectors to selectively impart pressurization energy to fuel trapped within said fuel pressurizing chambers when said pressurizing plungers advance and to recover pressurization energy from fuel trapped within said fuel pressurizing chambers when said pressurizing plungers retract;
• and
• d. a first interconnecting means for allowing fluidic interconnection of the fuel pressurizing chambers formed within said first set of injectors to allow fluidic linkage of the volume of fuel being simultaneously pressurized and depressurized within said interconnected fuel pressurizing chambers of said first set of injectors,
• wherein the total volume of fuel that is fluidically linked together within said first set of synchronized injectors substantially exceeds the volume of fuel injected during each injection event to avoid substantial loss of injection pressure during each injection event,
• wherein said camshaft linkage is arranged for reciprocating synchronously the pressurizing plungers of a second set of at least two injectors as the engine camshaft rotates to impart selectively pressurization energy to fuel trapped within the corresponding fuel pressurizing chambers of said second set of injectors when the pressurizing plungers of said second set of injectors advance and to recover pressurization energy from fuel trapped within said fuel pressurizing chambers when said pressurizing plungers retract, and further including a second interconnecting means for
• allowing fluidic interconnection of the fuel pressurizing chambers of said second set of synchronized injectors to allow fluidic linkage of the volume of fuel being simultaneously pressurized and depressurized within said interconnected fuel pressurizing chambers of said second set of injectors, said second set of synchronized injectors being out of phase by a predetermined amount with respect to said first set, wherein the total volume of fuel that is fluidically linked together within said second set of synchronized injectors substantially exceeds the volume of fuel injected during each injection event to avoid substantial loss of injection pressure during each injection event, and
• wherein each said injector of said second set of injectors includes a nozzle control valve having a closed position for preventing the flow of fuel into the corresponding combustion chamber and an open position in which fuel from said fluidically connected fuel pressurizing chambers of said first set of injectors is allowed to flow into the corresponding combustion chamber through the corresponding injection orifice.

A fuel injection system for an internal combustion engine having multiple combustion chambers, comprising

• a. a source of fuel at low pressure;
• b. a first set of injectors mounted for injecting fuel at high pressure into the combustion chambers, respectively, of the internal combustion engine, each said injector including
• i. an injector body containing a bore for receiving fuel at low pressure from said source of fuel and an injection orifice in fluid communication periodically with said bore, and
• ii. a pressurizing plunger mounted for reciprocation within said bore to form a fuel pressurizing chamber from which fuel may be withdrawn at relatively high pressure for injection into a corresponding combustion chamber of the engine through said injection orifice;
• c. actuating means for simultaneously reciprocating the pressurizing plungers of a set of at least two injectors to selectively impart pressurization energy to fuel trapped within said fuel pressurizing chambers when said pressurizing plungers advance and to recover pressurization energy from fuel trapped within said fuel pressurizing chambers when said pressurizing plungers retract;
• and
• d. a first interconnecting means for allowing fluidic interconnection of the fuel pressurizing chambers formed within said first set of injectors to allow fluidic linkage of the volume of fuel being simultaneously pressurized and depressurized within said interconnected fuel pressurizing chambers of said first set of injectors,
• wherein the total volume of fuel that is fluidically linked together within said first set of synchronized injectors substantially exceeds the volume of fuel injected during each injection event to avoid substantial loss of injection pressure during each injection event,
• wherein each said injector of said first set includes a nozzle control valve having a closed condition for preventing the flow of fuel into the corresponding combustion chamber and an open condition in which fuel from said fluidically connected fuel pressurizing chambers of said first set of injectors is allowed to flow into the corresponding combustion chamber through the corresponding injection orifice.

A fluid pressurizing system cyclically imparting pressurization energy to, and recovering pressurization energy from a fluid, comprising

• a. a source of fluid at low pressure;
• b. a plurality of pressurizing units mounted for discharging fluid at high pressure, each said pressurizing unit including;
• i. a unit body containing a bore for receiving fluid at low pressure from said source of fluid and a discharge passage in fluid communication periodically with said bore, and
• ii. a pressurizing plunger mounted for reciprocation within said bore to form a fluid pressurizing chamber from which fluid may be discharged at relatively high pressure;
• c. a mechanical linkage for simultaneously reciprocating the pressurizing plungers of a set of at least two pressurizing units as the mechanical linkage selectively imparts pressurization energy to fluid trapped within said pressurizing chambers when said pressurizing plungers advance and to recover pressurization energy from fluid trapped within said fluid pressurizing chambers when said pressurizing plungers retract;
• and
• d. a first interconnecting line for allowing selective fluidic interconnection of the pressurizing chambers formed within said first set of pressurizing units to allow fluidic linkage of the volume of fluid being simultaneously pressurized and depressurized within said interconnected fluid pressurizing chambers of said first set of pressurizing units,
• wherein the total volume of fluid that is fluidically linked together within said first set of synchronized pressurizing units substantially exceeds the volume of fluid discharged during each discharge event;
• wherein said first interconnecting line is fluidically connected to said source of fluid and further including a first pressure control valve moveable between an open condition in which fluid is allowed to flow in either direction between said source of fluid and said interconnected fluid pressurizing chambers of said first set of pressurizing units and a closed condition in which energy may be imparted to the fluid within said fluid pressurizing chambers of said first set of pressurizing units as the corresponding pressurizing plungers are advanced and in which energy may be recovered from the fluid within said pressurizing chambers of said first set of pressurizing units as said corresponding pressurizing plungers are retracted, and
• wherein each said pressurizing unit of said first set includes a nozzle control valve having a closed condition for preventing the discharge of fluid and an open condition in which fluid from said fluidically connected pressurizing chambers of said first set of pressurizing units is allowed to be discharged through a corresponding discharge passage.