Claims
- 1. An internal combustion engine comprisinga camshaft; a hub secured to said camshaft for rotation therewith, said hub having an external surface thereon; a housing circumscribing said hub, said housing having an internal surface thereon, said housing being rotatable with said hub and said camshaft and being oscillatable with respect to said hub and said camshaft; a plurality of driving vanes radially disposed in said housing and cooperating with said external surface of said hub; a plurality of driven vanes radially disposed in said hub and alternating with said plurality of driving vanes and cooperating with said internal surface of said housing; said plurality of driving and driven vanes defining a plurality of alternating advance and retard chambers; locking means for preventing relative motion between said housing and said hub in at least one position between a fully advanced position of said hub relative to said housing and a fully retarded position of said hub relative to said housing, said locking means being reactive to engine oil pressure; and means for controlling oscillation of said housing relative to said hub.
- 2. The internal combustion engine as claimed in claim 1, wherein said housing includes a first set of locking teeth and further wherein said locking means comprises:a locking plate circumscribing a portion of said camshaft; a locking ring connected to said locking plate, said locking ring including a second set of locking teeth being in engagement with said first set of locking teeth of said housing in a locked position to prevent relative circumferential motion between said hub and said housing, and being out of engagement with said first set of locking teeth in an unlocked position to permit relative circumferential motion between said hub and said housing; and resilient means for biasing said locking plate and said locking ring toward said locked position.
- 3. The internal combustion engine as claimed in claim 2, wherein said locking ring is coaxially positioned relative to the longitudinal axis of said camshaft and is moveable along the longitudinal axis of said camshaft between said locked position and said unlocked position.
- 4. The internal combustion engine as claimed in claim 3, wherein said locking plate has a radially extending flange and wherein said resilient means engages an axial surface of said radially extending flange.
- 5. The internal combustion engine as claimed in claim 4, wherein said locking means further comprises:a passage extending through said camshaft for delivering engine oil pressure to said locking plate, where engine oil pressure acts against an opposed axial surface of said radially extending flange of said locking plate to counteract a force imposed on said locking plate by said resilient means.
- 6. The internal combustion engine as claimed in claim 5 further comprising:a control valve for controlling flow of engine oil pressure into said passage extending through said camshaft.
- 7. The internal combustion engine as claimed in claim 6 fulrther comprising:an electronic engine control unit for controlling operation of said control valve to control whether said control valve operates in an on mode or in an off mode.
- 8. The internal combustion engine as claimed in claim 1, wherein said controlling means comprises:an electronic engine control unit; valuing means for directing engine oil pressure and being responsive to said electronic engine control unit; advancing means for communicating engine oil pressure between said valuing means and said plurality of advance chambers; and retarding means for communicating engine oil pressure between said valuing means and said plurality of said retard chambers.
- 9. The internal combustion engine as claimed in claim 8, wherein said advancing means includes neither a check valve nor a spool valve.
- 10. The internal combustion engine as claimed in claim 8, wherein said valuing means includes a control valve comprising:an advance control port communicating with said advancing means, a retard control port communicating with said retarding means, a supply port for supplying engine oil pressure, and an exhaust port for exhausting engine oil pressure.
- 11. The internal combustion engine as claimed in claim 8, wherein each of said plurality of driving vanes is biased against each of said plurality of said driven vanes to maximize the volume of either said plurality of advance chambers or said plurality of retard chambers, and said controlling means including either said advancing means or said retarding means respectively supplying one of said plurality of advance chambers and said plurality of retard chambers with engine oil pressure to counterbalance said plurality of driving vanes biased against said plurality of driven vanes.
- 12. An internal combustion engine comprising:a camshaft; a hub secured to said camshaft for rotation therewith, said hub having an external surface thereon; a housing circumscribing said hub to define a fluid chamber therebetween, said housing having an internal surface thereon, said housing being rotatable with said hub and said camshaft and being oscillatable with respect to said hub and said camshaft; a plurality of driving vanes radially disposed in said housing and extending in an inwardly radial direction therefrom into said fluid chamber and cooperating with said external surface of said hub; a plurality of driven vanes radially disposed in said hub and extending radially outwardly therefrom into said fluid chamber and cooperating with said internal surface of said housing; said plurality of driving and driven vanes dividing said fluid chamber into a plurality of advance chambers and a plurality of retard chambers circumferentially interspersed with said plurality of advance chambers; locking means for preventing relative motion between said housing and said hub in at least one position between a fully advanced position of said hub relative to said housing and a fully retarded position of said hub relative to said housing, said locking means being reactive to engine oil pressure; and means for controlling oscillation of said hub relative to said housing, said controlling means comprises means for porting said plurality of advance and retard chambers with engine oil pressure to relatively displace said plurality driving and driven vanes.
- 13. The internal combustion engine as claimed in claim 12, wherein said housing includes a first set of locking teeth and further- wherein said locking means comprises:a locking plate circumscribing a portion of said camshaft; a locking ring connected to said locking plate, said locking ring including a second set of locking teeth being in engagement with said first set of locking teeth of said housing in a locked position to prevent relative circumferential motion between said hub and said housing, and being out of engagement with said first set of locking teeth in an unlocked position to permit relative circumferential motion between said hub and said housing, said locking plate being coaxially positioned relative to the longitudinal axis of said camshaft and moveable along the longitudinal axis of said camshaft between said locked and said unlocked position; and resilient means for biasing said locking plate and said locking ring toward said locked position.
- 14. The internal combustion engine as claimed in claim 13, said locking means further comprising:a radially extending flange thereon and wherein said resilient means engages an axial surface of said radially extending flange; and a passage extending through said camshaft for delivering engine oil pressure to said locking plate, where engine oil pressure acts against an opposed axial surface of said radially extending flange of said locking plate for counterbalancing a force imposed on said locking plate by said resilient means.
- 15. The internal combustion engine as claimed in claim 14 further comprising:an on/off control valve for controlling flow of engine oil pressure into said passage extending through said camshaft; and an electronic engine control unit for controlling operation of said on/off control valve to control whether said on/off control valve operates in an on mode or in an off mode.
- 16. The internal combustion engine as claimed in claim 12, wherein said controlling means further comprises:an electronic engine control unit; valving means for directing engine oil pressure and being responsive to said electronic engine control unit; advancing means for communicating engine oil pressure between said valving means and said plurality of advance chambers, wherein said advancing means comprises an advancing fluid passage through said camshaft, said hub, and said locking means, said advancing fluid passage communicating with said advance chambers, whereby engine oil pressure flows finely through said advancing fluid passage when said locking means is in said unlocked position and engine oil pressure is blocked when said locking means is in said locked position; and retarding means for communicating engine oil pressure between said valving means and said plurality of said retard chambers, wherein said retarding means comprises a retarding fluid passage through said camshaft, said hub, and said locking means, said retarding fluid passage communicating with said retard chambers, whereby engine oil pressure flows freely through said retarding fluid passage when said locking means is in said unlocked position and engine oil pressure is blocked when said locking means is in said locked position.
- 17. The internal combustion engine as claimed in claim 16, wherein said advancing means includes neither a check valve nor a spool valve.
- 18. The internal combustion engine as claimed in claim 16, wherein said valving means includes a four-way pulse-width-modulated valve comprising:an advance control port communicating with said advancing means, a retard control port communicating with said retarding means, a supply port for supplying engine oil pressure, and an exhaust port for exhausting engine oil pressure.
- 19. The internal combustion engine as claimed in claim 16, wherein each of said plurality of driving vanes is biased against each of said plurality of said driven vanes to maximize the volume of either said plurality of advance chambers or said plurality of retard chambers, and said controlling means including either said advancing means or said retarding means respectively supplying one of said plurality of advance chambers and said plurality of retard chambers with engine oil pressure to counterbalance said plurality of driving vanes biased against said plurality of driven vanes.
- 20. An internal combustion engine comprising:a crankshaft; a camshaft linked to and rotatably driven by said crankshaft; a hub secured to said camshaft for rotation therewith, said hub having an external surface thereon, said hub further having inwardly extending radial slots open to said external surface and being circumferentially spaced apart, said hub being non-oscillatable with respect to said camshaft; a housing circumscribing said hub, said housing having an internal surface thereon, said housing being rotatable with said hub and said camshaft and being oscillatable with respect to said hub and said camshaft, said housing further having outwardly extending radial slots open to said internal surface and being circumferentially spaced apait, said internal surface being circumferentially larger than said external surface of said hub thereby defining a fluid chamber therebetween; a plurality of driving vanes radially and slidably disposed in said outwardly extending radial slots of said housing and corresponding in quantity to said outwardly extending radial slots of said housing, each of said plurality of driving vanes having an inner edge engaging said external surface of said hub, said plurality of driving vanes being spring-loaded radially inwardly to ensure constant contact with said external surface of said hub; a plurality of driven vanes radially and slidably disposed in said inwardly extending radial slots of said hub and corresponding in quantity to said inwardly extending radial slots of said hub, each of said plurality of driven vanes having an outer edge engaging said internal surface of said housing, said plurality of driven vanes being spring-loaded radially outwardly to ensure constant contact with said internal surface of said housing; said plurality of driving and driven vanes defining a plurality of advance chambers and a plurality of retard chambers circumferentially alternatively interspersed among said plurality of advance chambers within said fluid chamber, said plurality of alternating advance and retard chambers being fluid tightly separated from each other; locking means for preventing relative motion between said housing and said hub in at least one position between a fully advanced position of said hub relative to said housing and a fully retarded position of said hub relative to said housing, said locking means being reactive to engine oil pressure; and means for controlling oscillation of said hub relative to said housing, said controlling means comprises means for porting said plurality of advance chambers, and means for porting said plurality of retard chambers, said controlling means being capable of supplying said plurality of alternating advance and retard chambers with engine oil pressure and being capable of exhausting said plurality of alternating advance and retard chambers of engine oil pressure to relatively displace said plurality of driving and driven vanes.
- 21. The internal combustion engine as claimed in claim 20, wherein said housing includes a first set of locking teeth and further wherein said locking means comprises:a locking plate circumscribing a portion of said camshaft; a locking ring connected to said locking plate, said locking ring including a second set of locking teeth being in engagement with said first set of locking teeth of said housing in a locked position to prevent relative circumferential motion between said hub and said housing, and being out of engagement with said first set of locking teeth in an unlocked position to permit relative circumferential motion between said hub and said housing; and resilient means for biasing said locking ring and locking plate toward said locked position.
- 22. The internal combustion engine as claimed in claim 21, wherein said controlling means further comprises:an electronic engine control unit; valving means for directing engine oil pressure and being responsive to said electronic engine control unit; advancing means for communicating engine oil pressure between said valving means and said plurality of advance chambers; and retarding means for communicating engine oil pressure between said valving means and said plurality of said retard chambers.
- 23. The internal combustion engine as claimed in claim 20, wherein said advancing means includes neither a check valve nor a spool valve.
CROSS-REFERENCES
The present application is related to pending application Ser. No. 09/450,456 filed Nov. 29, 1999, and entitled “Variable Valve Timing with Actuator Locking for Internal Combustion Engine”, by inventor Roger T. Simpson Additionally, the present application is related to copending application Ser. No. 09/488,903 filed on the same date herewith, and entitled “Multi-Position Variable Cam Timing System Having a Vane-Mounted Locking-Piston Device”, by inventors Roger T. Simpson, and Michael Duffield, and thus is incorporated by reference herein. Finally, the present application is related to copending application Ser. No. 9/592,624 also filed on the same date herewith, and entitled “Control Valve Strategy for Vane-Typc Variable Camshaft Timing System”, by inventors Roger T. Simpson and Michael Duffield and thus is also incorporated by reference herein.
US Referenced Citations (11)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0 924 392 A2 |
Jun 1999 |
EP |