Claims
- 1. A solenoid operated exhaust gas recirculation valve for an internal combustion engine, comprising:a valve housing having a central chamber, an inlet passage, an outlet passage, and an exhaust gas inlet passage having an inlet opening, each of said passages being in fluid communication with said central chamber; a valve member positioned in and moveable within said central chamber, said valve member having a hollow valve stem and a valve head, said valve head having at least one opening formed therein to receive exhaust gas therethrough such that it can pass into said hollow valve stem; a solenoid assembly for reciprocating said moveable valve member between a closed position wherein said valve head engages a valve seat located at said exhaust gas inlet opening to prevent the flow of exhaust gas from said exhaust gas inlet passage into said central chamber and a fully open position wherein said valve head is disposed from said valve seat allowing exhaust gas to flow from said exhaust gas inlet passage into said central chamber to mix with air flowing in from said inlet passage; said valve member being subjected to an initial bias which produces a force tending to move the moveable valve member toward the closed position; an expandable device that produces a force responsive to said initial bias to produce a force tending to urge the valve away from the closed position, said expandable device having an upper and a lower surface, whereby exhaust gas passing through said hollow valve stem, exerts a downward force on said upper surface of said expandable device to counteract the pressure exerted by the exhaust gas on said valve head, whereby at all positions of the valve member between the closed and fully open positions, the pressures acting on the valve member and the expandable device are equal so that said valve member remains in the desired position to allow the appropriate amount of exhaust gas to enter said central chamber.
- 2. The solenoid operated valve of claim 1, wherein said expandable device is a diaphragm.
- 3. The solenoid operated valve of claim 2, wherein said solenoid assembly comprises a wound coil which receives current from said engine controller to control the movement of the valve member and wherein the movement of the valve member is proportional to the amount of current in said wound coil.
- 4. The solenoid operated valve of claim 3, wherein said sensor is a Hall field effect sensor.
- 5. The solenoid operated valve of claim 3, wherein said sensor is an inductive sensor.
- 6. The solenoid operated valve of claim 3, wherein said moveable valve member moves away from said diaphragm to allow exhaust gas into said central chamber.
- 7. The solenoid operated valve of claim 6, wherein said diaphragm is positioned in a diaphragm chamber which is located between said valve housing and said solenoid assembly.
- 8. The solenoid operated valve of claim 7, wherein said valve stem is supported by a pair of bearings to align said valve stem with said valve seat.
- 9. The solenoid operated valve of claim 8, wherein said diaphragm is attached to said valve stem in said diaphragm chamber.
- 10. The solenoid operated valve of claim 9, wherein said diaphragm is in communication with a diaphragm retainer and moves in response thereto.
- 11. The solenoid valve of claim 10, wherein said solenoid assembly includes a push rod that reciprocates in response to excitation of said coil, said push rod being in communication with said diaphragm retainer.
- 12. The solenoid valve of claim 11, wherein said movement of said valve head away from said valve seat is proportional to the movement of said push rod.
- 13. The solenoid valve of claim 12, wherein said position of said push rod is sensed by said position sensor to determine the position of said valve member.
- 14. The solenoid valve of claim 13, further comprising a return spring that biases said valve toward said closed position.
- 15. The solenoid valve of claim 14, wherein said solenoid valve is intended for use in a diesel engine.
- 16. A solenoid exhaust gas recirculation valve, comprising:a valve body having a central chamber, an exhaust inlet passage, an outlet passage, and a moveable valve member in said central chamber controlling the flow between said inlet passage and said outlet passage, said valve member including a valve stem and a valve head; a solenoid assembly for reciprocating the moveable valve member between an open position and a closed position, wherein in said closed position said valve head contacts a valve seat located at the inlet of said exhaust gas inlet passage, said solenoid assembly including a wound coil, a bobbin in contact with one surface of said wound coil, and a flux tube in contact with a surface of said bobbin; the valve member being subjected to exhaust gas in said closed position that produces a force tending to move the moveable poppet away from said closed position, said valve member including an armature attached to and encapsulating a portion thereof; an expandable device which produces a force responsive to said exhaust gas pressure for generally equalizing the force tending to move the moveable valve member away from the closed position and maintaining the moveable valve member in said closed position; said expandable device including an expandable chamber that is in fluid communication with the exhaust inlet passage when said valve member is closed; and said valve being configured such that a radial gap exists between said solenoid assembly and said armature for equalizing pressure in the solenoid.
- 17. The solenoid valve of claim 16, wherein an annular bearing is seated on said flux tube for vertically positioning said armature and thus said valve head.
- 18. The solenoid valve of claim 17, wherein said expandable device includes a diaphragm that provides a spring force acting on said valve member.
- 19. The solenoid valve of claim 18, wherein said valve member has a passageway formed therethrough that establishes fluid communication between said expandable chamber and said exhaust inlet passage.
- 20. The solenoid valve of claim 19, further comparing a sensor housing attached to said solenoid assembly.
- 21. The solenoid valve of claim 20, wherein said sensor housing includes a Hall effect sensor for monitoring the position of the armature and the valve member.
- 22. The solenoid valve of claim 20, wherein said sensor housing includes an inductance sensor for monitoring the position of the armature and the valve member.
- 23. The solenoid valve of claim 16, wherein said valve is incorporated for use in an internal combustion engine.
- 24. The solenoid valve of claim 23, wherein said outlet passageway transfers exhaust gas from said central chamber downstream to a mixing chamber for mixing with boost air for use in operating said engine.
- 25. The solenoid valve of claim 16, wherein said valve housing further comprises at least one fluid annula in fluid communication with said central chamber for cooling said exhaust gas.
- 26. A method of constructing and calibrating a solenoid valve assembly comprising:slidably mounting an armature, including a wound coil, and poppet within a housing to form a solenoid subassembly; mounting a position sensor within the housing; placing the subassembly in a test chamber; calibrating the position sensor to sense the position of the poppet by (a) energizing the coil to the maximum required poppet stoke and ensuring that the poppet is in a fully open position; and (b) deenergizing the coil to a no poppet stoke condition and ensuring that the poppet is in a closed position abutting the valve seat; and attaching the calibrated subassembly to a base valve housing which is configured to mount an engine.
- 27. The method of claim 26 further comprising:crimping an insert to the outside of the housing prior to calibrating the position sensor.
- 28. A solenoid operated exhaust gas recirculation valve for an internal combustion engine, comprising:a valve housing having a central chamber, an exhaust gas inlet passage having an inlet opening and an outlet passage both of said passages in fluid communication with said central chamber; a valve member positioned in and moveable within said central chamber, said valve member having a valve stem and a valve head said valve stem including a passageway having an opening in communication with said exhaust gas inlet passageway; a solenoid assembly for reciprocating said moveable valve member between a closed position wherein said valve head engages a valve seat located at said exhaust gas inlet passage into said central chamber and a fully open position wherein said valve head is displaced from said valve seat allowing exhaust gas to flow from said exhaust gas inlet passage into said central chamber; said valve member being subjected to an initial pressure in said closed position which produces a force tending to move the moveable valve member away from said closed position; an expandable device that produces a force responsive to said initial pressure to produce a force tending to urge said valve head away from the closed position said expandable device further having a pressure exerted thereon by said exhaust gas from said valve stem passageway to counteract the pressure exerted by the exhaust gas on said valve head, whereby at all positions of the valve member between the closed and fully open positions, the pressures acting on the valve member and the expandable device are equal so that the valve member remains in the desired position to allow the appropriate amount of exhaust gas to enter said central chamber; and a sensor housing attached to said solenoid housing and including a position sensor to monitor the position of said valve member, said position sensor being in communication with an engine controller which controls the movement of said valve member in response to operating conditions of said engine.
Parent Case Info
The present application is a continuation-in-part of U.S. Provisional application Ser. No. 60/019,044, filed on May 20, 1996, which is a continuation-in-part of U.S. Provisional application Ser. No. 60/022,948, filed on Aug. 2, 1996.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
102e Date |
371c Date |
PCT/US97/08553 |
|
WO |
00 |
3/31/1999 |
3/31/1999 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO97/44580 |
11/27/1997 |
WO |
A |
US Referenced Citations (11)
Provisional Applications (2)
|
Number |
Date |
Country |
|
60/019044 |
May 1996 |
US |
|
60/022948 |
Aug 1996 |
US |