초록 ▼

Manufacturing imperfections and component failures in the fuel system of an engine, can lead to non-uniform torque production among the cylinders. Non-uniform cylinder torques can be observed as small engine speed fluctuations about the average engine speed at any given operating point. Engine speed

Manufacturing imperfections and component failures in the fuel system of an engine, can lead to non-uniform torque production among the cylinders. Non-uniform cylinder torques can be observed as small engine speed fluctuations about the average engine speed at any given operating point. Engine speed data contains fluctuations at different frequencies. The amplitude of fluctuations at some known frequencies tell about the health of the fuel injectors and the engine. In the present invention, the instantaneous engine speed data is filtered by discrete second-order band-pass filters to find the engine speed fluctuations at particular frequencies. The output of the filters is identical to power spectral density of speed signal at those frequencies. The amplitude of each filter output is then compared to a predetermined threshold value. If the amplitude is bigger than this threshold, it indicates the existence of low fueling or high fueling fuel injectors. If the amplitude is bigger than a second higher threshold, it indicates the existence of dead fuel injectors.

대표청구항 ▼

Manufacturing imperfections and component failures in the fuel system of an engine, can lead to non-uniform torque production among the cylinders. Non-uniform cylinder torques can be observed as small engine speed fluctuations about the average engine speed at any given operating point. Engine speed

Manufacturing imperfections and component failures in the fuel system of an engine, can lead to non-uniform torque production among the cylinders. Non-uniform cylinder torques can be observed as small engine speed fluctuations about the average engine speed at any given operating point. Engine speed data contains fluctuations at different frequencies. The amplitude of fluctuations at some known frequencies tell about the health of the fuel injectors and the engine. In the present invention, the instantaneous engine speed data is filtered by discrete second-order band-pass filters to find the engine speed fluctuations at particular frequencies. The output of the filters is identical to power spectral density of speed signal at those frequencies. The amplitude of each filter output is then compared to a predetermined threshold value. If the amplitude is bigger than this threshold, it indicates the existence of low fueling or high fueling fuel injectors. If the amplitude is bigger than a second higher threshold, it indicates the existence of dead fuel injectors. on the movable device (6) in such a way that they can run in guides (15, 15a, 15b) in the following three directions, respectively: horizontal at right angles to, and horizontal parallel to, the forward direction (F) or the reverse direction (F1), and vertical. stic thin-wall nozzle that projects dome-shaped at the atmosphere side from the communicating duct. 11. A teat cup according to claim 1, wherein a lower clamping position of the liner extends almost in parallel to the supporting face. 12. A teat cup according to claim 1, further comprising: at least one thin-wall portion that is formed in the circumferential wall of a hose part of the liner determined for receiving the teat. 13. A teat cup according to claim 12, further comprising: a thin-wall portion is arranged at least partially between wall and/or web parts of the liner having an anchoring and supporting function, respectively. 14. A teat cup according to claim 12, wherein negative pressure, atmospheric or excess pressure, can be applied to the external outer face of the thin-wall portion. 15. A teat cup according to claim 14, further comprising: at least two axially or radially offset thin-wall portions that are formed at the liner, wherein pressures can be separately applied to exterior spaces radially adjacent thereto or the latter are communicated with each other at least partially through a duct adapted to be throttled. 16. A teat cup according to claim 1, further comprising: a partly annular thin-wall portion that is formed in the area of the head portion of the liner above or below an upper clamping position or an inserting ring having an undulated, inwardly or outwardly turned shape in a state free of differential pressure. 17. A teat cup according to claim 15, wherein the exterior space adjacent to the thin-wall portion can be controlled by atmospheric or excess pressure preferably in response to the vacuum of an interior space of the liner located below the teat or by excess pressure in response to a change of position of the teat cup. 18. A teat cup according to claim 1, wherein the wall thicknesses of the thin-wall portion and of the thicker wall portions of the liner are selected in response to the time sequence of the phases of the milking operation, with respect to the massage phase and the closing vis-a-vis the negative pressure source. 19. A teat cup according to claim 1, wherein the teat cup sleeve and the liner are formed in one piece by appropriately selecting the wall thickness of the liner and of the thin-wall portions. 20. A teat cup according to claim 1, wherein the direction of deformation of the liner is predetermined by an appropriate selection of the wall thicknesses of the liner or the shaping of the teat cup sleeve. 21. A teat cup according to claim 1, wherein the closing is effected by arching the liner wall located at the outside of the closing. 22. A liner for a teat cup according to claim 1, further comprising: an obliquely extending closing which can be closed by an opposite liner wall, is formed in a circumferential wall of a hose part determined for receiving the teat.