Fluid sprinkling – spraying – and diffusing – Fluid pressure responsive discharge modifier* or flow... – Fuel injector or burner
Reexamination Certificate
1998-09-29
2001-01-09
Hook, James (Department: 3752)
Fluid sprinkling, spraying, and diffusing
Fluid pressure responsive discharge modifier* or flow...
Fuel injector or burner
C239S533110, C239S533140, C239S585100, C239S596000, C239S601000, C239S900000
Reexamination Certificate
active
06170763
ABSTRACT:
BACKGROUND INFORMATION
German Patent Application No. 41 21 310 describes a fuel injector which has a valve-seat member on which a fixed valve seat is formed. A valve-closure member, axially movable in the injector, interacts with this valve seat formed in the valve-seat member. Contiguous to the valve-seat member in the downstream direction is a flat jet-aligning plate, in which, facing the valve seat, provision is made for an H-shaped depression as an inlet area. Contiguous to the H-shaped inlet area in the downstream direction are four spray-discharge orifices, so that a fuel to be sprayed can be distributed via the inlet area right up to the spray-discharge orifices. In this case, the flow geometry in the jet-aligning plate is not intended to be influenced by the valve-seat member. Rather, a flow passage downstream of the valve seat in the valve-seat member is designed to be so wide, that the valve-seat member has no influence on the orifice geometry of the jet-aligning plate.
A lack of influence of the valve-seat member on the orifice geometry of an orifice plate arranged at a fuel injector applies also to fuel injectors which are described in U.S. Pat. No. 4,699,323 or in European Patent No. 0 310 819. In these patents, the orifice plates have functional planes with different orifice geometries; however, an overlap of the inlet areas of the spray orifices in the orifice plate by the valve-seat member is in no way desired or allowed.
German Patent Application No. 196 07 277 describes a fuel injector having an orifice plate which has a plurality of functional planes exhibiting different orifice geometries. The individual functional planes of the orifice plate are built up on one another by galvanic metal deposition (multilayer electroplating). In this injector as well, the valve-seat member should never limit or overlap the inlet openings in the upper functional level of the orifice plate.
SUMMARY OF THE INVENTION
The fuel injector of the present invention, has the advantage that a uniform, very fine atomization of the fuel is achieved in a simple manner without additional energy, a particularly high atomization quality and a jet formation adapted to the respective requirements being attained. This is achieved in that an orifice plate arranged downstream of a valve seat has an orifice geometry for a complete axial passage of the fuel, the orifice geometry being bounded by a valve-seat member surrounding the fixed valve seat. Thus, the valve-seat member already assumes the function of influencing the flow in the orifice plate, which in the conventional orifice plates, could be achieved by their upper layers or functional planes. In another embodiment of the present invention, an S-course is attained in the flow for improving the fuel atomization, since the valve-seat member, with a lower end face, overlaps the outlet orifices of the orifice plate.
The S-course in the flow attained by the geometrical arrangement of the valve-seat member and the orifice plate allows the formation of bizarre jet shapes with a high atomization quality. The orifice plates, in conjunction with appropriately designed valve-seat members, render possible jet cross-sections for single, double and multi-jet sprays in countless variants, such as rectangles, triangles, crosses and ellipses. Such unusual jet shapes permit a precise, optimal adaptation to predetermined geometries, e.g. to various intake-manifold cross-sections of internal combustion engines. The advantages resulting from this are a shape-adapted utilization of the available cross-section for the homogeneously distributed, exhaust-decreasing introduction of the mixture, and avoidance of exhaust-harmful film accumulations on the wall of the intake manifold. Consequently, such a fuel injector can reduce the exhaust-gas emission of the internal combustion engine, and fuel consumption can likewise be reduced.
With the assistance of galvanic metal deposition, orifice plates can be simultaneously produced in very large quantities in a reproducible manner with extreme precision and cost-effectively. Furthermore, this manner of manufacturing allows extremely great freedom in shaping, since the contours of the orifices in the orifice plate are freely selectable. Particularly in comparison to silicon orifice plates, in which the attainable contours are strictly predefined because of the crystal axes (truncated pyramids), flexible shaping is advantageous. Metallic deposition, especially compared to the manufacture of silicon disks, offers the advantage of a very large variety of materials. The most varied metals with their different magnetic properties and hardness can be used in manufacturing the orifice plates.
It is advantageous to form the orifice plates with two functional planes, one functional plane being characterized by an orifice geometry which, viewed across its axial thickness, is constant, the orifice geometry differing suitably from the orifice geometry of the subsequent functional plane. Since the valve-seat member ultimately determines the inlet geometry into the orifice plate, two functional planes are already sufficient for attaining an S-shaped flow. Compared to multilayer or multilayered orifice plates, the advantages of a simpler, less costly and timereduced manufacture result, since on one hand, less metallic material has to be deposited, and on the other hand, it is possible to dispense with electroplating starting layers. Furthermore, the photoresist can be removed substantially more easily. In addition, accuracy can be better controlled when producing the orifice plates, because all the orifice contours of the orifice plate can be examined from an outer end face.
Quite generally, it can be stressed as an advantage of the fuel injector of the present invention, that it is possible to vary the jet pattern in a simple manner. Thus jet patterns which are flat, conical, which include a plurality of individual jets, and which are asymmetrical (directed on one side) can be generated particularly easily.
REFERENCES:
patent: 4699323 (1987-10-01), Rush et al.
patent: 4925111 (1990-05-01), Foertsch et al.
patent: 5402937 (1995-04-01), Buchholz et al.
patent: 5636796 (1997-06-01), Oguma
patent: 5766441 (1998-06-01), Arndt et al.
patent: 5899390 (1999-05-01), Arndt et al.
patent: 5924634 (1999-07-01), Arndt et al.
patent: 38 08 396 (1989-09-01), None
patent: 41 21 310 (1992-01-01), None
patent: 196 07 277 (1996-10-01), None
patent: 19527626 (1997-01-01), None
patent: 0 310 819 (1989-04-01), None
patent: 97 05378 (1997-02-01), None
Dantes G{umlaut over (u)}nter
Fuchs Heinz
Heyse Jorg
Evans Robin O.
Hook James
Kenyon & Kenyon
Robert & Bosch GmbH
LandOfFree
Fuel injection 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 Fuel injection valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fuel injection valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2524316