Fuel injection nozzle for internal combustion engines

Details Fuel injection nozzle for internal combustion engines Fuel injection nozzle for internal combustion engines

1995-12-15

1998-08-04

Kashnikow, Andres

Fluid sprinkling, spraying, and diffusing

Fluid pressure responsive discharge modifier* or flow...

Resilient or deformable terminal outlet

23953314, 239596, B05B 130

Patent

active

057881618

DESCRIPTION:

BRIEF SUMMARY
PRIOR ART

The invention is based on a fuel injection nozzle for internal combustion engines. In a fuel injection nozzle of this kind, known for instance from U.S. Pat. No. 1,589,239, the resilient valve diaphragm is embodied as a flat disk, with a reinforcement in the form of a hub that defines the flow opening. The outer peripheral region of the diaphragm is fastened firmly against the retaining body with a union nut, so that the diaphragm rests by an annular edge of the flow opening of a certain prestressing, which defines the opening pressure, on the valve cone of the nozzle needle, which protrudes axially into the pressure chamber of the holding body. When fuel is supplied and a pressure is built up in the pressure chamber, the diaphragm bulges away from the nozzle needle toward the combustion chamber, so that the peripheral edge of the flow opening lifts away from the nozzle needle valve cone and uncovers an annular valve gap. The hub that defines the flow opening is disposed on the perforated diaphragm in the form of a reinforcement, so that the bending or bulging is concentrated not only on the region near the flow opening but rather is distributed over the entire surface area. This embodiment of the diaphragm still leaves something to be desired in terms of durability, however, since each time the diaphragm bulges, very high strains arise in the annular region adjoining the fastened outer region.
German Democratic Republic Patent Disclosure DD-A 1 803 has also disclosed a fuel injection nozzle with a resilient, peripherally fastened valve diaphragm, whose inner peripheral region surrounding the flow opening cooperates in valvelike fashion with a nozzle needle. To prevent the valve diaphragm from tearing at the flow opening even after relatively long operation, the inner peripheral region forming the seat region is formed by an extrusion in the opposite direction of the injection direction, and the annular region adjoining it toward the outside is reinforced by a resilient annular disk. In this form of valve diaphragm as well, high strains occur near the fastened outer peripheral region and impair the durability of the valve diaphragm.


ADVANTAGES OF THE INVENTION

The fuel injection nozzle according to the invention having the characteristics of the body of claim 1 has the advantage that because of the bulging of the valve diaphragm in the direction counter to that in which pressure is imposed, no critical strains occur in the diaphragm upon valve opening by bending counter to the bulging over the entire region. Because the resilience is limited to a certain amount, the strains remain within a certain limit range, and so the diaphragm has very high fatigue strength under compressive strains, making for a long useful life.
As a result of how the bulge is embodied, the annular region, which adjoins the fastened outer peripheral region and rises steeply toward the pressure chamber, and the flatly rising inner region prevent the generation of impermissibly high peak strains, so that the fatigue life of the valve diaphragm is increased substantially. This is achieved because at the critical points, dictated by geometry, noncritical compressive strains are superimposed on the critical tensile strains.
By means of the provisions recited hereinafter, advantageous features and improvements of the fuel injection nozzle are possible.


BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention are shown in the drawing and will be described in detail below.
FIG. 1 shows a fuel injection nozzle in longitudinal section;
FIGS. 2 and 3 show two alternative exemplary embodiments of a fuel injection nozzle with an adjustable nozzle needle in longitudinal section;
FIG. 4 shows the valve region of the fuel injection nozzle of FIGS. 1-3 in section on a larger scale;
FIGS. 5-7 show three alternatively shaped valve d iaphragms in cross section;
FIGS. 8-13 show alternative features of the valve region and the associated diagrams of the opening characteristic of fuel injection nozzles of FIGS. 1-3;
FIGS. 1

REFERENCES:
patent: 1589245 (1926-06-01), Scott
patent: 2965311 (1960-12-01), Gascoigne
patent: 3827638 (1974-08-01), Halvorsen
patent: 3831860 (1974-08-01), Gullaksen et al.
patent: 4013229 (1977-03-01), Rohs
patent: 4628576 (1986-12-01), Gianchino et al.
patent: 4647013 (1987-03-01), Giachino et al.
patent: 4907748 (1990-03-01), Gardner et al.
patent: 5193743 (1993-03-01), Romann et al.
patent: 5323966 (1994-06-01), Buchholz et al.

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