Fluid handling – Line condition change responsive valves – With separate connected fluid reactor surface
Patent
1997-12-19
1999-10-19
Hepperle, Stephen M.
Fluid handling
Line condition change responsive valves
With separate connected fluid reactor surface
137459, 137463, G05D 1608
Patent
active
059671777
DESCRIPTION:
BRIEF SUMMARY
PRIOR ART
The invention is based on a pressure regulating for a fuel delivery system of an internal combustion engine.
Usually a pressure regulating valve is used to regulate the pressure in a fuel delivery system of an internal combustion engine. The pressure regulating valve is disposed on the pressure side of the fuel pump. A portion of the fuel delivered by the fuel pump is supplied to the engine via injection valves. In many engines, each cylinder is provided with an injection valve. It is necessary that at every moment, the injection valves are injecting the precisely correct fuel quantity, wherein the permissible scatter between the injection valves is extremely small. The excess quantity of fuel not required by the engine is returned to the fuel reservoir via the pressure regulating valve. In so doing, the pressure regulating valve regulates the pressure on the pressure side of the fuel pump. In different motor vehicles, components that influence the return pressure are inserted in the return line that leads from the pressure regulating valve to the fuel reservoir. The components can, for example, be a jet pump and/or a control valve.
In order to make a motor vehicle with an internal combustion engine as quiet as possible, the endeavor is made to minimize the noise produced by the pressure regulating valve, which in the past could not be achieved at a justifiable cost. In particular, components present in the return line that influence the return pressure have a considerable negative influence on the noise behavior of the pressure regulating valve. Another disadvantage of the known pressure regulating valves is that vibrations are produced in the fuel, which in the injection valves have a negative effect on a uniform distribution of the fuel.
In order to improve the noise behavior of the pressure regulating valve and in order to prevent the impairing influence of vibrations on the fuel metering of the injection valves, a number of embodiments of different pressure regulating valves have been tested. In the course of the tests, the length of the sealing gap between the closing body of the pressure regulating valve and the valve seat was varied in different pressure regulating valves, but this did not make it possible to eliminate the negative noise behavior of the pressure regulating valve. In another measurement series, for example, the diameter of the connection opening that adjoins the sealing gap was varied. This, too, did not allow any satisfactory improvement of the noise behavior to be achieved. By enlarging the diameter of the connection opening, noise stemming from high-turbulence flows could in fact be slightly reduced, but in turn, the reactions coming from the return line, via the pressure regulating valve, and back onto the pressure side were so strong that it was clear that this would not lead to the achievement of a satisfactory solution. In particular if there were fluctuating through flows and components in the return line that influenced the pressure (e.g. jet pumps), then in order to keep the reactions onto the pressure side of the pressure regulating valve within limits, the diameter of the connection opening could not be great enough that the noise stemming from high-turbulence flows could have been prevented. In another series of tests, the through flow of fuel was throttled by a throttle downstream of the sealing gap. However, in order to achieve a noticeable reduction of noise, the throttle had to be chosen so small that the pressure regulating valve was given throttling characteristics and was no longer suitable for regulating a pressure. It was therefore clear that the installation of a throttle downstream of the sealing gap could not be considered for purposes of noise reduction. In addition, pressure regulating valves were also tested in which the closing body of the pressure regulating valve is provided with a friction element that provides a friction between the valve housing and the closing body when the sealing gap is opened and closed. The noise behavior could be no
REFERENCES:
patent: 4936342 (1990-06-01), Kojima et al.
patent: 5076320 (1991-12-01), Robinson
patent: 5220941 (1993-06-01), Tuckey
Greigg Edwin E.
Greigg Ronald E.
Hepperle Stephen M.
Robert & Bosch GmbH
LandOfFree
Pressure regulating valve does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pressure regulating valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pressure regulating valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2044563