1. A system for diagnosing malfunctions in a variable valve actuation system comprising:
a rocker arm assembly comprising:
a first arm with a first end;
a second arm with a first end pivotally connected to the first arm, the first end of the first arm and the first end of the second arm both pivoting about a same pivot axis;
a hydraulically-operated latch assembly functioning to secure the first arm to the second arm when latched for operation in a first operating mode and functioning to allow the first arm to move relative to the second arm when unlatched in a second operating mode;
a source of pressurized fluid;
a hydraulic valve coupled to the source of pressurized fluid, adapted to provide pressurized fluid to the hydraulically-operated latch assembly;
a gallery connecting the hydraulic valve to the hydraulically-operated latch assembly;
a pressure transducer for indicating a pressure in the gallery; and
a control unit coupled to the hydraulic valve and the pressure transducer, adapted to:
accept a hydraulic pressure input from the pressure transducer; and
identify motion of a latch of the hydraulically-operated latch assembly based upon the hydraulic pressure input from the pressure transducer.
2. The system of claim 1 wherein the control unit is further adapted to:
sense engine operation parameters; and
actuate the hydraulic valve.
3. The system of claim 1 wherein the control unit is further adapted to:
identify when the latch has been actuated based upon the hydraulic pressure input from the pressure transducer.
4. The system of claim 1 wherein the control unit is further adapted to: calculate a velocity of the latch based upon the hydraulic pressure input from the pressure transducer.
5. The system of claim 1 wherein the control unit is further adapted to: calculate when the latch is moving slower than a predetermined acceptable velocity.
6. The system of claim 1 wherein the control unit is further adapted to: store previously calculated latch velocities and determine changes in the velocities over time to identify a probability that the latch will not respond within a predetermined acceptable time period.
7. The system of claim 1 wherein the control unit is further adapted to: calculate a velocity of the latch based upon a measured slope of a time vs. hydraulic pressure input from the pressure transducer.
8. The system of claim 1, further comprising a second source of pressurized fluid connected to the hydraulically-operated latch assembly.
9. A system for diagnosing malfunctions in a variable valve actuation system comprising:
a hydraulically-operated latch assembly;
a first source of pressurized fluid;
a hydraulic valve coupled to the first source of pressurized fluid and adapted to provide pressurized fluid through the hydraulic valve to the hydraulically-operated latch assembly;
a gallery connecting the hydraulic valve to the hydraulically-operated latch assembly;
a pressure transducer for measuring a hydraulic pressure in the gallery; and
a control unit coupled to the hydraulic valve and the pressure transducer, adapted to:
receive a hydraulic pressure input from the pressure transducer; and
identify motion of a latch of the hydraulically-operated latch assembly in the variable valve actuation system based upon an input from the pressure transducer.
10. The system of claim 9, further comprising:
a rocker arm assembly comprising:
a first arm with a first end; and
a second arm with a first end pivotally connected to the first arm, the first end of the first arm and the first end of the second arm both pivoting about a same pivot axis and
wherein the hydraulically-operated latch assembly secures the first arm to the second arm when the latch is latched for operation in a first operating mode and functioning to allow the first arm to move relative to the second arm when unlatched in a second operating mode.
11. The system of claim 9, further comprising a second hydraulically-operated latch assembly also provided with a first source of pressurized fluid, wherein the hydraulically-operated latch assembly and the second hydraulically-operated latch assembly are operably connected to rocker arm assemblies of two cylinders of an internal combustion engine.
12. The system of claim 9, wherein the hydraulically-operated latch assembly further comprises a dual-feed hydraulic lash adjuster (DFHLA).
13. The system of claim 9, wherein the gallery comprises an upper gallery and is a pressurized vessel of hydraulic fluid.
14. The system of claim 9, further comprising a second source of pressurized fluid connected to the hydraulically-operated latch assembly.
15. The system of claim 14, wherein the second source of pressurized fluid comprises a lower gallery and is a pressurized vessel of hydraulic fluid.
16. A system for diagnosing malfunctions in a variable valve actuation system comprising:
a hydraulically-operated latch assembly;
a hydraulic valve coupled to a first source of pressurized fluid and adapted to provide pressurized fluid through the hydraulic valve to the hydraulically-operated latch assembly;
a pressure transducer for measuring a pressure of the pressurized fluid provided by the first source of pressurized fluid; and
a control unit coupled to the hydraulic valve and the pressure transducer, adapted to:
receive a hydraulic pressure input from the pressure transducer; and
identify motion of a latch of the hydraulically-operated latch assembly in a variable valve actuation system based upon an input from the pressure transducer.
17. The system of claim 16, further comprising an upper gallery connecting the hydraulic valve to the hydraulically-operated latch assembly.
18. The system of claim 16, further comprising a second source of pressurized fluid connected to the hydraulically-operation latch assembly.
19. The system of claim 18, wherein the second source of pressurized fluid comprises a lower gallery.
20. The system of claim 16, further comprising:
a rocker arm assembly comprising:
a first arm with a first end; and
a second arm with a first end pivotally connected to the first arm, wherein the first end of the first arm and the first end of the second arm both pivoting about a same pivot axis, and
wherein the hydraulically-operated latch assembly secures the first arm to the second arm when the latch is latched for operation in a first operating mode and functioning to allow the first arm to move relative to the second arm when unlatched in a second operating mode.
21. The system of claim 16, wherein one indication of a malfunction in the variable valve actuation system comprises an unexpected time shifting of a pressure increase or pressure decrease during latching or unlatching.
22. The system of claim 16, wherein one indication of a malfunction in the variable valve actuation system comprises a difference from an expected rate of increase or decrease of pressure during latching or unlatching.
23. The system of claim 16, wherein the control unit is adapted to yield an indication of a malfunction in the variable valve actuation system independent of direct measurement of a valve lift or a latch pin movement.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-12. (canceled)
13. A method of producing a stamping with an enlarged functional surface, out of a flat strip, wherein the flat strip at closing is clamped between an upper part, including a shearing punch, a pressure pad for the shearing punch, a V-shaped projection arranged on the pressure pad and an ejector, and a lower part, including a cutting die, an ejector and an inner form punch and the V-shaped projection is pressed into the flat strip, the method comprising:
clamping an untreated clamped flat strip before cutting is initiated;
preforming a negative with regard to a cutting direction with a preforming element into the cutting die in a direction opposite to the cutting direction that corresponds to the expected edge rollover with regard to size and geometry at cutting to create at preformed area, including an allowance so as to generate a material volume at a side of the rollover in a mirror-inverted form; and
supporting the preformed area of the clamped flat strip by the preforming element at a start of, and during, the cutting.
14. A method according to claim 13, wherein said stamping is a workpiece produced by fine blanking.
15. A method according to claim 13, wherein process parameters for the preforming in the preformed area are determined depending on the material type, shape andor geometry of the workpiece by a virtual forming simulation.
16. A method according to claim 15, wherein said process parameters include the geometry andor the material volume of the edge rollover.
17. A method according to claim 13, wherein the process parameters for the preforming are iteratively determined depending on the material type, shape andor geometry of the workpiece by measuring at least two real fine blanking parts.
18. A method according to claim 17, wherein said process parameters include the geometry andor the material volume of the edge rollover of the area to be preformed.
19. A method according to claim 13, wherein the preforming is carried out in a separate pre-stage or before starting the cutting process in a common stage, the process parameters of which are respectively adjusted according to the determined edge rollover.
20. A method according to claim 13, wherein said preforming element includes a coining stamp.
21. A method according to claim 19, wherein the preforming in the direction to the pressure pad and the cutting in the following step are realized at parts with a thickness of up to 10 mm, and small and large dimensions.
22. A method according to claim 21, wherein said thickness is 3 to 5 mm
23. A method according to claim 13, wherein said preforming element is used as the ejector of the fine blanking tool.
24. A method according to claim 19, wherein the preforming in the direction to the stamp and the cutting in the complex cutting operation are realized at parts with medium thickness of 3 to 7 mm, and small and medium-sized dimensions.
25. A method according to claim 13, wherein no material is shifted along the cutting line determined by the cutting die and the punch.
26. A device for producing a stamping with an enlarged functional surface, out of a flat strip, comprising:
an upper part including a pressure pad with a V-shaped projection, a shearing punch guided in the pressure pad; and
a lower part including a cutting die and an ejector, the flat strip being clamped between the upper part and the lower part during operation of the device wherein the flat strip is positioned between the pressure pad and cutting die and the V-shaped projection is pressed into the flat strip, said lower part further including at least one coining stamp arranged before a cutting stage, said coining stamp being operable to act against a cutting direction to negatively pre-form a material volume on a rollover side corresponding to an expected edge rollover, the coining stamp and the ejector in the cutting stage having a contour on respective active sides thereof, each respectively defined by a preforming angle which corresponds with the geometry of the expected edge rollover plus an allowance, the ejector supporting the preformed area during cutting.
27. A method according to claim 26, wherein said stamping is a workpiece produced by fine blanking.
28. A device according to claim 26, wherein the preforming angle at the coining stamp and the ejector amounts to 20\xb0 to 40\xb0.
29. A device according to claim 26, wherein the preforming angle at the coining stamp and the ejector is 30\xb0
30. A device for producing a stamping with an enlarged functional surface, out of a flat strip, comprising:
an upper part including a pressure pad with a V-shaped projection, a shearing punch guided in the pressure pad; and
a lower part including a cutting die and an ejector, the flat strip being clamped between the upper part and the lower part during operation of the device wherein the flat strip is positioned between the pressure pad and cutting die and the V-shaped projection is pressed into the flat strip, said ejector being in a form of at least one coining stamp operable to act against a cutting direction to negatively pre-form a material volume on a rollover side corresponding to an expected edge rollover, the at least one coining stamp in the cutting stage having a contour on an active side thereof, defined by a preforming angle which corresponds with the geometry of the expected edge rollover plus an allowance, the ejector supporting the preformed area during cutting.
31. A method according to claim 30, wherein said stamping is a workpiece produced by fine blanking.
32. A device according to claim 30, wherein the preforming angle at the coining stamp amounts to 20\xb0 to 40\xb0.
33. A device according to claim 30, wherein the preforming angle at the coining stamp is 30\xb0