Control module for controlling hydraulically actuated intake/exhaust valves and a fuel injector

Information

  • Patent Grant
  • 6360728
  • Patent Number
    6,360,728
  • Date Filed
    Thursday, August 5, 1999
    24 years ago
  • Date Issued
    Tuesday, March 26, 2002
    22 years ago
Abstract
A control module which controls camless hydraulically driven intake and exhaust valves and an hydraulically driven fuel injector of an internal combustion engine. The module contains a valve assembly to control the intake valve, a valve assembly to control the exhaust valve and a valve assembly to control the fuel injector. The valve assemblies preferably each contain a pair of solenoid actuated two-way spool valves. The solenoids are actuated by digital pulses provided by an electronic assembly within the module. The solenoid actuated spool valves control the flow of a hydraulic fluid to and from the fuel injector and the intake and exhaust valves. The hydraulic fluid opens and closes the intake and exhaust valves. The hydraulic fluid also actuates the fuel injector to eject a fuel into a combustion chamber of the engine. The electronic assembly of each module can be connected to a main microprocessor which provides commands to each assembly. Each electronic assembly processes the command, feedback signals from the hydraulically actuated devices and historical data to insure a desired operation of the fuel injector and intake and exhaust valves.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a control module for controlling the actuation of hydraulically driven fuel injectors and intake/exhaust valves for an internal combustion engine.




2. Description of Related Art




Compression ignition internal combustion engines contain a plurality of reciprocating pistons located within combustion chambers of an engine block. Associated with each piston is a fuel injector that sprays a highly pressurized fuel into the combustion chamber. The fuel is mixed with air that is introduced into the chamber through an intake valve. After combustion the exhaust flows out of the chamber through an exhaust valve. The injection of fuel and movement of the intake and exhaust valves are typically controlled by mechanical cams. Cams are relatively inefficient and susceptible to wear. Additionally, the cams do not allow the engine to vary the timing of fuel injection, or the opening and closing of the intake/exhaust valves.




U.S. Pat. No. 5,255,641 issued to Schechter and assigned to Ford Motor Co. and U.S. Pat. No. 5,339,777 issued to Cannon and assigned to Caterpillar Inc. disclose hydraulically driven intake/exhaust valves that do not require cams to open and close the valves. The movement of the intake/exhaust valves is controlled by a solenoid actuated fluid valve(s). When the fluid valve(s) is in one position an hydraulic fluid flows into an enclosed stem portion of the intake/exhaust valve. The hydraulic fluid exerts a force on the stem which opens the valve. When the fluid valve(s) is switched to another position the intake/exhaust valve moves back to the original closed position. The fluid valve(s) is switched by an electronic controller. The controller can vary the timing of the intake/exhaust valves to optimize the performance of the engine.




U.S. Pat. No. 5,460,329 issued to Sturman discloses an hydraulically driven fuel injector. The Sturman injector contains a solenoid actuated fluid valve that is connected to an electronic controller. The valve and controller control the timing and amount of fuel injected into the combustion chamber of the engine. To date the camless intake/exhaust valves disclosed in Schechter and Cannon, and the hydraulically driven fuel injector disclosed in Sturman have always been provided as separate units which must be individually assembled to the engine block. Each unit has separate electrical wires that must be connected to the engine controller. Connecting a number of wires and separate actuating components increases the assembly cost of the engine. Additionally, because of manufacturing tolerances there may be variations in the lengths of the wires. A variation in the wire length may change the timing and amplitude of the driving signals transmitted to the solenoid actuated control valves. A change in the driving signals may degrade the performance of the engine. It would be desirable to provide a single electronic hydraulic module that controls camless hydraulically driven intake/exhaust valves and a fuel injector of a combustion chamber. It would also be desirable if the single module had a minimum number of external wires.




The solenoid actuated fluid valves for the intake/exhaust valves are typically connected to a single microprocessor which can vary the valve timing in response to variations in a number of input parameters such as fuel intake, hydraulic rail pressure, ambient temperature, etc. The microprocessor can vary the start time and the duration of the driving signal provided to the fluid valves to obtain a desired result. Because of variations in manufacturing tolerances, different valves may have different responses to the same driving pulse. For example, given the same driving pulse one intake valve may open for a shorter period of time than another intake valve in the same engine.




The Schechter patent discusses a process wherein each valve is calibrated to determine a correction value. The correction value is stored within the electronics of the engine and used to either shorten or lengthen the driving pulse provided to each valve so that the valves are all open for the same time duration. Although effective in compensating for variations in manufacturing tolerances, the Schechter technique does not compensate for variations that occur during the life of the engine. For example, one of the valves may stick and require more energy to move into an open position. It would be desirable to provide a module which can individually analyze the intake/exhaust valves and fuel injector to insure that the corresponding combustion chamber is operating at an optimum performance during the life of the engine.




The hydraulic fluid for hydraulically driven fuel injectors is typically provided by a pump and a series of fluid lines. The fluid system typically contains a spring biased pressure relief valve which opens to insure that the fluid pressure does not exceed a certain level. The pump performs work to overcome the spring of the relief valve during the by-pass mode of the system. It would be desirable to provide an hydraulic system for a camless engine, wherein the fluid pressure can be controlled without any additional components, or without requiring additional work by the pump to reduce the pressure within the system.




Some internal combustion engines contain a “turbocharge” assembly which varies the air flow into the combustion chambers. Some turbochargers contain complicated electronic devices to vary and control the air flow into the chamber. The electronic devices add to the cost and complexity of the engine. It would be desirable to provide a single control module that can control a fuel injector, an intake valve, an exhaust valve and a turbocharge unit.




SUMMARY OF THE INVENTION




The present invention is a control module which controls camless hydraulically driven intake and exhaust valves and an hydraulically driven fuel injector of an internal combustion engine. The module contains a valve assembly to control the intake valve, a valve assembly to control the exhaust valve and a valve assembly to control the fuel injector. The valve assemblies preferably each contain a pair of solenoid actuated two-way spool valves. The solenoids are actuated by digital pulses provided by an electronic assembly within the module. The solenoid actuated spool valves control flow of a hydraulic fluid to and from the fuel injector and the intake and exhaust valves. The hydraulic fluid opens and closes the intake and exhaust valves. The hydraulic fluid also actuates the fuel injector to eject a fuel into a combustion chamber of the engine. The electronic assembly of each module can be connected to a main microprocessor which provides commands to each assembly. Each electronic assembly processes the commands, feedback signals from the hydraulically actuated devices and historical data to insure a desired operation of the fuel injector and intake and exhaust valves. The module is a relatively light and compact component that can be mounted onto the combustion chamber of the engine. Each module typically requires no more than three wires which minimizes the complication and cost of assembly. One of the modules can be actuated to provide a by-pass for the hydraulic system of the engine. Additionally, the timing of the exhaust valves can be varied to control a turbocharger.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a top perspective view showing a control module mounted to an internal combustion engine;





FIG. 2

is a cross-sectional view of the control module;





FIG. 3

is a cross-sectional view of the control module showing an exhaust-valve moving to an open position;





FIG. 4

is a cross-sectional view of a fuel injector;





FIG. 5

is a cross-sectional view of a fuel injector;





FIG. 6

is cross-sectional view of a fluid control valve;





FIG. 7

is a schematic of an electrical system of the present invention;





FIG. 8

is a schematic showing a turbocharger;





FIG. 9

is a schematic of a hydraulic system for a plurality of modules.











DETAILED DESCRIPTION OF THE INVENTION




Referring to the drawings more particularly by reference numbers,

FIGS. 1-3

show a control module


10


of the present invention. The module


10


is typically mounted to a head


12


of an engine block


14


. The block


14


has a plurality of combustion chambers


16


which each contain a reciprocating piston (not shown). Coupled to each combustion chamber


16


is a fuel injector


18


, an intake air valve


20


and an exhaust valve


22


. The fuel injector


18


, intake valve


20


and exhaust valve


22


are each hydraulically driven devices that do not require cams. The module


10


controls the operation of the fuel injector


18


, the intake valve


20


and the exhaust valve


22


by directing hydraulic fluid to and from the devices


18


,


20


and


22


.




As shown in

FIGS. 2 and 3

, the module


10


includes a housing


24


. Within the housing


24


is a fuel injector valve assembly


26


, an intake valve assembly


28


and an exhaust valve assembly


30


. The housing


24


also has a pair of cavities


32


that contain the stem


34


of the intake valve


20


and the stem


34


of the exhaust valve


22


. The intake valve assembly


28


controls the flow of a hydraulic fluid to move the valve stem


34


in a reciprocating motion between an open position and a closed position. Likewise, the exhaust valve assembly


30


controls the hydraulic fluid to move the valve stem


34


of the exhaust valve between open and closed positions.




The exhaust valve stem


34


is attached to a head


36


that engages a pin


38


and a power pin


40


. The pins


38


and


40


move the exhaust valve


22


from a closed position to an open position. The head


36


is biased into a closed position by a pair of return pins


42


located within a pair of corresponding channels


44


of the housing


24


. The channels


44


are connected to a pressurized fluid line


46


within the housing


24


. The fluid line


46


and channels


44


contain a pressurized hydraulic fluid which applies a pressure to the return pins


42


that pushes the head


36


and valve


22


into an upward closed position.




The pin


38


and power pin


40


are located within an hydraulic chamber


48


that is connected to a common line


50


. In the preferred embodiment, the exhaust valve assembly


30


includes two solenoid actuated two-way spool valves


52


and


54


. Valve


52


is connected to the pressurized fluid line


46


and the common line


50


. Valve


54


is connected to the common line


50


and a drain line


56


. The housing


24


may also have a vent line


58


which allows fluid that leaks past the pins


38


and


40


to vent to the drain line


56


.




As shown in

FIG. 3

, when valve


52


is open and valve


54


is closed, pressurized hydraulic fluid flows into the chamber


48


to push the pins


38


and


40


. The pins


38


and


40


have a larger area than the return pins


42


so that the hydraulic fluid pushes the exhaust valve


22


to the open position. The power pin


40


moves until the pin


40


engages a step


60


in the housing


24


. The pin


38


continues to move the exhaust valve


22


even after progress of the power pin


40


is impeded by the step


60


. The power pin


40


provides an additional force to initially open the exhaust valve


22


. It being understood that the exhaust within the combustion chamber is relatively high when the exhaust valve


22


is closed. The power pin


40


provides enough force to overcome the high exhaust pressure. When the exhaust valve


22


is open there is a rapid reduction in the exhaust pressure. Only the smaller pin


38


is required to move the exhaust valve


22


against the lower pressure exhaust within the combustion chamber.




When valve


52


is closed and valve


54


is open the chamber


48


is connected to the drain line


56


. The return pins


42


push the head


36


and move the exhaust valve


22


back to the closed position. The module


10


may include a exhaust valve position sensor assembly


62


that includes a magnet


64


and a Hall effect sensor


66


. The Hall effect sensor


66


provides an output voltage that decreases as the pin


38


and exhaust valve


22


move away from the magnet


64


.




The intake valve stem


32


also has a head


70


that is coupled to a pin


72


and a pair of return pins


74


. The return pins


74


are located within channels


75


connected to a pressurized fluid line


76


. The pin


72


is located within an hydraulic chamber


78


that is connected to a common line


80


. In the preferred embodiment, the intake valve assembly


28


includes a pair of solenoid actuated two-way spool valves


82


and


84


. Valve


82


is connected to the pressurized fluid line


76


and the common line


80


. Valve


84


is connected to the common line


80


and a drain line


86


. The housing


24


may also have vent line


88


.




When valve


82


is open and valve


84


is closed the hydraulic fluid pushes the pin


72


and moves the intake valve


20


from the closed position to the open position. When valve


82


is closed and valve


84


is open the return pins


74


push the head


70


and move the intake valve


20


back to the closed position. The module


10


may also have an intake valve position sensor assembly


90


that includes a magnet


92


and a Hall effect sensor


94


.




In the preferred embodiment, the fuel injector valve assembly


18


includes a pair of solenoid actuated two-way spool valves


96


and


98


. Valve


96


is connected to a pressurized fluid line


100


and a common line


102


. Valve


98


is connected to the common line


102


and a drain line


104


. The common line


102


is connected to a cylinder port


106


of the housing


24


. As shown in

FIG. 1

, the cylinder port


106


may be connected to a corresponding port of the fuel injector by a fluid line


108


. The drain line


104


may contain a pressure sensor


110


that is used to monitor the operation of the fuel injector


18


.




When valve


96


is open and valve


98


is closed, pressurized hydraulic fluid is provided to the fuel injector


18


. When valve


98


is open and valve


96


is closed hydraulic fluid is allowed to flow from the fuel injector


18


and into the drain line


104


.





FIGS. 4 and 5

show a preferred embodiment of a fuel injector


18


. The fuel injector


18


includes a top block


120


that is attached to an outer shell


122


. The outer shell


122


contains an intensifier block


124


, a passage block


126


and a needle housing


128


. The needle housing


128


has a plurality of apertures


130


that allow fuel to be ejected from the fuel injector


18


.




The fuel injector


18


includes an intensifier


132


which has a piston


134


and a head


136


. The head


136


has a cavity


138


that is in fluid communication with a cylinder passage


140


. The cylinder passage


140


is connected to the fluid line


108


and cylinder port


106


of the module housing


24


. The intensifier


132


is coupled to a pair of return pins


142


located within a pair of corresponding channels


144


in block


124


. The channels


144


are connected to a supply port


146


that is coupled to the pressurized hydraulic fluid. The area of the intensifier head


136


is larger than the return pins


142


so that the intensifier


132


moves in a downward direction when pressurized fluid is provided at cylinder passage


140


. The return pins


142


move the intensifier


132


back to the original position when the cylinder passage


140


is connected to drain. The cavity portion


145


beneath the intensifier head


136


is typically coupled to a drain line to prevent build up of hydrostatic pressure which may counteract the downward movement of the intensifier


132


.




The intensifier piston


134


moves within a fuel chamber


146


in block


124


. The fuel chamber


146


is coupled to a pair of fuel ports


148


by a passage


150


and a one-way check valve


152


. The fuel chamber


146


is also connected to a needle chamber


154


by passages


156


and


158


in blocks


126


and


128


, respectively. The needle chamber


154


contains a needle valve


160


. The needle valve


160


is biased into a closed position by a pin


162


that is in fluid communication with a passage


163


that is connected to the channels


144


and pressurized hydraulic fluid.




When the module


10


is actuated so that valve


96


is open and valve


98


is closed, pressurized fluid flows from the cylinder port


106


of the module


10


and into the cavity


138


of the intensifier head


136


. As shown in

FIG. 6

, the hydraulic fluid moves the intensifier


132


and pushes fuel that is within the fuel chamber


146


into the needle chamber


154


. The check valve


152


prevents the fuel from flowing back through the fuel ports


148


. The pressure of the fuel lifts the needle valve


160


into an open position so that fuel is ejected through the apertures


130


.




When valve


96


is closed and valve


98


is open, the cylinder passage


140


is coupled to the drain line


104


of the module


10


. The return pins


142


push the intensifier


132


in an upward direction. The movement of the intensifier piston


134


draws more fuel into the fuel chamber


146


. The pin


162


pushes the needle valve


160


back to the closed position wherein the process can be repeated.





FIG. 6

shows a preferred embodiment of a solenoid actuated two-way spool valve used in the module


10


. The valve includes a spool


170


located within a spool chamber


172


. The spool


170


has a pair of annular grooves


174


that allow fluid communication between a pair of inlet ports


176


and an outlet port


178


. By way of example, for valve


96


the inlet ports


176


may be the pressurized fluid line


100


and the outlet port


178


may be the common line


102


. The dual inlet ports


176


provides a valve wherein the fluid forces exerted on the spool


170


are in opposite directions. The opposing fluid forces offset each other, thereby providing a dynamically balanced valve.




Each valve has a first solenoid


180


and a second solenoid


182


. Each solenoid


180


and


182


includes a coil


184


wound around a bobbin


186


. The solenoids


180


and


182


are secured by end caps


188


inserted into the housing


24


. When energized the first solenoid


180


moves the spool


170


to a first position wherein fluid is allowed to flow from the inlet ports


176


to the outlet port


178


. When the second solenoid


182


is energized the spool


170


moves to a second position so that the spool


170


prevents fluid from flowing through the valve. The spool


170


preferably contains an inner channel


190


that prevents fluid from being trapped between the ends of the spool


170


and the end caps


188


.




In the preferred embodiment the spool


170


and end caps


188


are constructed from a magnetic steel such as 52100. The module housing


24


may also be constructed from a magnetic steel material. The magnetic steel retains enough magnetism to provide a magnetic force which holds the spool


170


in position even when power to the solenoids is terminated. The valve can therefore be switched with a short digital pulse that is provided to one of the solenoids


180


and


182


.




Referring to

FIG. 1

, the module


10


preferably contains an electronic assembly


200


that provides the digital driving pulses that switch the fluid control valves and actuate the fuel injector


18


, and intake


20


and exhaust


22


valves. The electronic assembly


200


includes a number of integrated circuits


202


mounted to a printed circuit board


204


. The printed circuit board


204


is connected to the solenoids of the fluid control valves by internal wires


206


within the module


10


. The circuit board


204


is also connected to three wires


208


that extend from the module


10


. Two of the wires typically provide electrical power to the integrated circuits


202


while the remaining wire provides a conduit for digital logic signals to and from the electronic assembly


200


.




As an alternate embodiment, the wires which carry digital signals may be filter optic cables coupled to corresponding photometers and photodetectors. The fiber optic system can operate at relatively high rates and are not susceptible to electrical noise such as electromagnetic interference from the engine.




The present invention provides a relatively small low cost module that can be readily mounted to the head of an engine. The module


10


requires a minimal number of external wires that need to be connected to the remaining electronics of the engine. Each module


10


can also be connected to diagnostic equipment so that individual combustion chambers can be tested and analyzed.





FIG. 7

shows an electronic system


220


. The system


220


includes a main engine controller


222


that is connected to the electronic assemblies


200


of the engine cylinder modules for each combustion chamber. Although only one engine cylinder module


200


is shown, it is to be understood that the main controller


222


is connected to a plurality of cylinder modules


200


.




The main controller


222


is typically a microprocessor that is connected to a plurality of engine sensors


224


such as air temperature, engine speed, etc. The main controller


222


provides a series of commands to the cylinder module


200


. Each cylinder module


200


contains a microprocessor


226


which receives the commands from the main processor


222


, process the commands and provides outputs to actuate the fuel injector


18


, and intake


20


and exhaust


22


valves.




The cylinder module


200


typically contains electronic driver circuits


228


that drive the solenoids of the fluid control valves. The cylinder module


200


may also have both volatile (RAM)


230


and non-volatile (ROM) memory


232


devices that store data that can be processed by the processor


226


. The ROM device


230


can store software routines that are used by the processor


226


to actuate the injector


18


and valves


20


and


22


. The microprocessor


226


also receives feedback signals from the intake valve position sensor


90


, the exhaust valve position sensor


62


and the pressure sensor


110


.




The processors


226


for each module can process the input commands, feedback signals and stored data to provide a desired actuation of the injector


18


and the valves


20


and


22


. Each injector and intake/exhaust valve may respond differently for a given digital pulse generated by a cylinder module. Additionally, the ROM device


232


may contain corrective factors for each device


18


,


20


or


22


. The corrective factors may be determined in a calibration routine of the module


10


, injector


18


and valves


20


and


22


. The correction factors can be used to vary the timing and duration of the digital driving pulses provided to the spool valves.




Additionally, each module


10


can compensate for variations in individual components by sensing the movement of the devices and then adjusting the digital pulse during the next cycle. For example, the cylinder module


200


may provide a digital pulse to the valves


82


and


84


to open the intake valve


20


. The intake position sensor


90


provides feedback on the actual movement of the valve


20


. If the valve


20


did not move at the desired times or for a desired stroke the cylinder module


200


may store the feedback and utilize the data to adjust the digital pulse for the next cycle. Likewise, the processor


226


may determine the amount of fuel from the pressure of the hydraulic fluid flowing from the cylinder passage


140


of an injector


18


as sensed by the pressure sensor


110


. The processor


226


can use this data to correct the digital driving pulse for the next cycle. The cylinder module continuously updates the driving signal for each cycle or after a predetermined number of cycles. The present invention thus provides a local processing capability that can update, process and compensate for variations in the injector


18


and valves


20


and


22


during the life of the engine.




The modules


10


can also be used to control other functions of a car engine. For example, it is sometimes desirable to utilize the combustion chambers to slow down the speed of the engine in a process commonly referred to as Jake breaking. In a Jake break routine air is introduced to the combustion chamber but not fuel. The intake and exhaust are actuated so that the engine performs work to compress the air within the chamber. The work generated to compress the air reduces the engine speed. The main controller


222


may generate command signals to enter a Jake brake routine, wherein the processors


226


of the modules actuate the valves


20


and


22


so that the engine pistons compress air. The processors


222


and


226


can provide commands and digital pulses to vary the timing of the valves


20


and


22


to obtain a desired breaking result depending upon engine speed, etc.





FIG. 8

shows another utility of the modules. The engine may have a turbocharger assembly


240


that controls the air flow into the combustion chamber. The assembly


240


may include an exhaust turbine


242


located within the exhaust manifold


244


of the engine and an intake turbine


246


located within the intake manifold


248


of the engine. The intake turbine


246


is connected to the exhaust turbine


242


by a shaft


248


so that turbine


246


rotates with turbine


242


.




The module


10


can control the opening of the exhaust valve


22


to control the flow of exhaust across the exhaust turbine


242


and the timing and speed at which the intake turbine


246


rotates. Varying the speed of the intake turbine


246


changes the air flow into the combustion chambers. The module


10


can therefore control the flow of air into the combustion chamber by varying the movement of the exhaust valve


22


. It being understood that the module


10


may also control the opening of the intake valve


20


to further control the flow of air.





FIG. 9

shows an hydraulic fluid system


260


for actuating the injectors


18


and valves


20


and


22


. The system


260


includes a low pressure pump


262


and a high pressure pump


264


. The output of the high pressure pump


264


is connected to a rail fluid line


266


. The rail line


266


is connected to the pressurized fluid lines


46


,


76


and


100


of the modules


10




a-d


. The system


260


also has a drain line


268


that is connected to the drain lines


56


,


86


and


104


of the modules


10




a


-


10




d


. The system may further have a one-way check valve


270


in the rail line


266


, a filter


272


between the pumps and a reservoir


274


of hydraulic fluid. The rail pressure can be sensed by a pressure sensor


276


that is connected to the microprocessor


222


.




One of the modules


10




a-d


is connected to a by-pass line


278


of the rail. The by-pass line


278


and module


10


a can be used to control the rail pressure within the system. By way of example, the by-pass line


278


may be connected to the pressurized fluid line


76


of the intake valve assembly


28


of module


10




a


, although it is to be understood that the by-pass line


278


may be connected to the exhaust valve assembly


30


, or the fuel injector valve assembly


26


.




When the intake valve


22


is not being actuated, the valves


82


and


84


of the intake assembly


28


may be opened to allow the fluid within the rail line


266


to flow to the drain line


268


to reduce the rail pressure. Consequently, the intake valve assembly


28


may have a first mode wherein valve


82


is open and valve


84


is closed to allow fluid to open the intake valve


20


, a second mode wherein valve


82


is closed and valve


84


is open to close the valve


20


, and a third mode wherein valves


82


and


84


are open to provide a by-pass function. The by-pass function is provided without any additional components. Additionally, the pump does not have to work to maintain the valves in the open position as required with spring biased relief valves of the prior art. The microprocessor


222


can sense the rail pressure through the sensor


276


and open the valves to control the rail pressure of the system, accordingly.




Referring to

FIGS. 2

,


3


and


8


, in operation, the microprocessor


222


may receive an input signal to increase the engine speed. The processor


222


provides an output command to the cylinder modules. The processors


226


of the modules


10


process the command and provide output driving signals to actuate the intake valve assemblies


28


and open the intake valves


20


. After a calculated time period the processors


226


of the modules provide output signals to close the intake valves


20


.




In accordance with a software routine and the input command the module processors


226


provide output signals to actuate the fuel injector


18


at desired times and for desired time intervals. The output signals may be unique for each module to compensate for variations in components. The module processors


226


eventually provide output signals to open and close the exhaust valves


22


. The sensors provide feedback data which can be stored and used in the next cycle(s).




While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art.



Claims
  • 1. A fluid control system for an internal combustion engine which contains a first hydraulically controlled device and a second hydraulically controlled device, comprising:a pump that pumps a fluid from an outlet port; a pressurized rail line coupled to said outlet port of said pump; a drain line; and, a first valve assembly that is connected to said pressurized rail line, said drain line, and the first hydraulically controlled device, said first valve assembly can be switched into either a first, second, or third mode, wherein the first hydraulically controlled device is coupled to said pressurized rail line when said first valve assembly is in the first mode, and coupled to said drain line when said first valve assembly is in the second mode, said pressurized rail line is coupled to said drain line when said first valve assembly is in the third mode.
  • 2. The system as recited in claim 1, wherein said first valve assembly contains a pair of two-way spool valves.
  • 3. The system as recited in claim 2, wherein each two-way control valve includes a pair of solenoids that move a spool.
  • 4. The system as recited in claim 3, further comprising a first electronic assembly which provides power to said solenoids of said first valve assembly and a second electronic assembly which provides power to said solenoids of said second valve assembly.
  • 5. The system as recited in claim 4, wherein said spools of said two-way valves are latched into a position by a digital pulse provided by said electronic assemblies.
  • 6. The system of claim 1, wherein said first valve assembly includes a housing which has a fuel injector valve bore and a fuel injector valve assembly that has a valve which is located within said fuel injector valve bore.
  • 7. The system of claim 6, wherein said fuel injector valve assembly includes a pair of solenoids that move a spool.
  • 8. The system of claim 7, further comprising an electronic assembly that is located within said housing and which provides power to said solenoids.
  • 9. The system of claim 8, wherein said electronic assembly provides a plurality of digital pulses to said solenoids.
  • 10. The system of claim 9, wherein said spool is latched into one of two positions.
  • 11. The system of claim 6, wherein said fuel injector valve assembly includes a pair of two-way spool valves.
  • 12. The system of claim 1, wherein said first valve assembly includes:a housing which has an intake bore; and, an intake valve assembly that has a valve which is located within said intake valve bore.
  • 13. The system of claim 12, wherein said intake valve assembly includes a pair of solenoids that move a spool.
  • 14. The system of claim 13, further comprising an electronic assembly that is located within said housing and which provides power to said solenoids.
  • 15. The system of claim 14, wherein said electronic assembly provides a plurality of digital pulses to said solenoids.
  • 16. The system of claim 15, wherein said spool is latched into one of two positions.
  • 17. The system of claim 12, wherein said intake valve assembly includes a pair of two-way spool valves.
  • 18. The system of claim 1, wherein said first valve assembly includes:a housing which has an exhaust bore; and, a hydraulically driven intake valve that extends from said housing; hydraulically driven exhaust valve that extends from said housing; a fuel injector valve assembly that is located within said housing and controls a flow of an hydraulic fluid to the fuel injector; an intake valve assembly that is located within said housing and controls a flow of the hydraulic fluid to said intake valve; and an exhaust valve assembly that has a valve which is located within said exhaust valve bore.
  • 19. The system of claim 18, wherein said exhaust valve assembly includes a pair of solenoids that move a spool.
  • 20. The system of claim 19, further comprising an electronic assembly that is located within said housing and which provides power to said solenoids.
  • 21. The system of claim 20, wherein said electronic assembly provides a plurality of digital pulses to said solenoids.
  • 22. The system of claim 21, wherein said spool is latched into one of two positions.
  • 23. The system of claim 18, wherein said exhaust valve assembly includes a pair of two-way spool valves.
Parent Case Info

This application is a continuation of application Ser. No. 08/799,296, filed Feb. 13, 1997, now issued as U.S. Pat. No. 5,970,956.

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Entry
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Continuations (1)
Number Date Country
Parent 08/799296 Feb 1997 US
Child 09/369497 US