US3592392A

US3592392A - Electromagnetic fuel injection spray valve

Info

Publication number: US3592392A
Authority: US
Inventors: Robert Huber
Original assignee: Societe des Procedes Modernes dInjection SOPROMI
Current assignee: Societe des Procedes Modernes dInjection SOPROMI
Priority date: 1968-06-11
Filing date: 1969-06-24
Publication date: 1971-07-13
Anticipated expiration: 1988-07-13
Also published as: DE1922709A1; CH492124A; FR2010631A1; GB1221767A

Abstract

Valve has a disc-shaped armature with a hollow shaft containing a compressed coil spring that holds the valve proper, carried at the end of the shaft, closed, except when the magnet is energized.

Description

United States Patent 1 13,592,392

l inventor Robe" Huber [56] References Cited 21] A I No gg fi'z UNITED STATES PATENTS [221 F1121 Jun; 24 1969 1,504,773 8/1924 Marston 239/585 [45] Patented July 3,3971 1,664,612 4/1928 French 239/585 1,664,616 4/1928 French 239/585 [73] Ass'gnee $32,33 21, Mmemes d f 1,999,221 4/1935 Walker et a1. 239/585 x Mum, France 3,070,024 12/1962 Romberg 310/18 UX 3,375,380 3/1968 Davis 310/29 3,404,299 10/1968 MacBlane 310/29 X 54 ELECTROMAGNETIC FUEL INJECTION SPRAY 'f 7 Benson Wood,

VALVE Assistant ExammerMIchael Y. Mar 9 Chims, 8 Drawing Figs Attorney-Spencer & Kaye [52] US. Cl 239/585,.

123/32, 137/4875, 310/29 ABSTRACT: Valve has a disc-shaped armature with a hollow [51] Int. Cl BOSb l/30 shaft containing a compressed coil spring that holds the valve [50] Field of Search 239/583, roper, carried at the end of the shaft, closed, except when the 584, 585; 123/32; 137/4875; 310/15, 29 magnet is energized.

PATENTED Jun 3 |97l sum 1 or z Invader.-

Obf-H: Hub" 3 M ,Q

3 QRMM S .the induction pipes of the engine, for example.

ELECTROMAGNETIC FUEL INJECTION SPRAY VALVE BACKGROUND OF THE INVENTION The invention relates to an electromagnetic fuel injection spray valve for internal combustion engines.

The electrically operated fuel injection devices of the prior art for internal combustion engines comprise an electromagnetic fuel injection spray valve which is opened, in dependence on the r.p.m., byan electronic control for a predetermined length of time, this period being dependent on various operating parameters of the engine, including r.p.m., throttle valve setting, and the suction in the induction pipe.

Fuel under pressure is continuously fed to the housing of these injection spray valves. As soon as the magnet coil is energized, the valve proper, connected to the magnet armature, frees the path to the spray nozzle, and fuel is sprayed into In one fuel injection spray valve of the prior art, the armature is designed as a cylindrical piston that projects into a cylindrical magnet coil and is moved against the resistance of a coil spring which biases the valve closed, the spring also being arranged within the magnet coil.

An injection valve of this kind operates satisfactorily at low fuel pressures, such as 2 atmospheres. But at higher fuel pressures, such as atmospheres, the magnetic force is not sufficient to raise the small cylindrical piston.

In another injection valve of the prior art, the valve embodies a disc-shaped armature and a horseshoe magnet; The magnetic force acting on the armature is substantially greater in this case, permitting higher fuel pressures and, therefore, shorter injection times. A diaphragm spring, held tensed in the valve housing, serves to close the valve. The spring, however, is very stiff; and it has been observed that the valve-closing force is greatly dependent on outside factors, such as thermal expansion, so that proper operation of the valve is adversely affected.

SUMMARY OF THE INVENTION An object of the invention is to provide a fuel injection spray valve that possesses the advantage, but not the'disadvantages, of these two prior art valves, and that is simple and inexpensive to manufacture.

The invention relates to an electromagnetic fuel injection spray valve, including a valve proper, a spray nozzle opened and closed by the valve, a disc-shaped armature for operating the valve, and wherein the improvement comprises a cylindrical hollow shaft incorporated by the armature, the valve proper being associated with the free end of the shaft, and a coil spring in the hollow of the shaft for biasing the valve to its closed position.

The use of a coil spring, for closing the valve, in combina tion with a disc-shaped armature ensures a strong magnetic force and the greatest possible independence from outside influences.

6O BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described, with reference to the FIGS. of the accompanying drawings, wherein:

FIG. I is a longitudinal section of one embodiment;

FIG. 2 is a view taken along line lI-II of FIG. 1;

FIG. 3 is a view taken along line III-Ill of FIG. 1;

FIG. 4 is a longitudinal section, taken at right angles to that of FIG. 1, of an embodiment having a modified armature.

FIG. Sis a view taken along line V-V of FIG. 4;

FIG. 6- is a longitudinal section of another modified annature;

FIG. 7 is a top view of the armature seen in FIG. 6; and

FIG. 8 is a longitudinal section of a third modification of the armature.

2 DESCRIPTION OF THE PREFERRED EMBODIMENTS The fuel injection spray valve shown in FIG. I has a housing comprising two parts I and 2. Within the housing is a magnet coil 3, which is wound on a synthetic Plastic former 4 and surrounds a laminated metal core 5 (see FIG. 2). The laminations form a rectangular core (as seen from above) held together by the former 4. The four corners of the core touch the round housing part 1 and hold the core centered within the housing I and 2.

The housing part 2 incorporates a bore 6 for the shaft 7a of a disc-shaped armature 7. The shaft is cylindrical and hollow, and carries at its lower end a valve'8 that cooperates with a valve seat 9 and periodically opens and closes the path for the fuel to the spray nozzle 10. Within the hollow of the shaft his a coil spring 11, which presses against a slider 12 that, in turn, presses directly against the magnet core 5. The spring 11 is compressed, and urges the armature 7, the armature shaft'7a, and the valve 8 at the end of the shaft 7a downwards against the valve seat 9. An annular spacer 13 made of a nonmagnetic material, such as a synthetic plastic, is arranged'between the armature 7 and the core 5 in order to prevent the latter two from touching each other and so to reduce the residual magnetism.

The spacer 13 can also be star-shaped, as indicated by the dashed line in-FIG. 3.

A fuel supply line 14 is connected to the housingpart 1', the fuel under about 20 atmospheres pressure enteringthe interi= or of the housing I and 2, passing through the bore 15, and entering the annular chamber 16, from which latter it is injected through the spray nozzle 10 and into the induction pipes of an engine, for example, whenever the valve 8 israised from its seat 9. To equalize the pressure, other bores 1 7' and 18 connect the hollow of the shaft 7a with the interior'of the housingv l and 2. The magnet armature 7, with its shaft 70, isso fitted in the

housing

1 and 2 that it is raised about 0.1 to 0.2 mm. when ever the magnet coil 3 is energized. A threaded ring I9'press'es' the housing part 2 directly against the magnet core 5. The necessary compression of the spring 11 can be easily adjusted before assembling the fuel injection valve by suitably dimen-' sioning the slider 12, for example. The stroke of the armatufe 7 is determinal by the dimensions of the housing part 2 and of the armature with the spacer I3.

The face of the armature adjacent to the core 5 is advantageously slightly conical, in order to facilitate movement of the fuel between the armature and the core when the arn'i'a ture rises.

In the embodiment shown in FIGS. 4 and 5, the housing" matures stroke. In this-embodiment, the armature'7 is still-' disc-shapedbut no longer circular in outline; instead two op-' posite segments'have been removed to reduce its weight.

Eddy currents are largely suppressed by incorporating.

milled parallel slots 22 in the armature 7.

In another embodiment shown in FIGS. 6 and-'7', the armature 7 includesthe hollow shaft 7a with its compression spring 11 and laminations 24 riveted onto a crosspiece 23, the

laminations 24 constituting the disc-shaped armature 7. Thismanner of forming the armature 7'of-laminations also reduces the appearance of eddy currents.

In still another embodiment, shown in FIG. 8, the hollow shaft 7a with its valve 8 is made of steel, and thedi'sc-shaped armature 7 is-made of soft iron and cemented or'w'elded to the shaft 7a. The interior of the shaft 7a houses-the-compression spring 11, which presses against an intermediate ri'ngpressin'g against theslider 12, which contacts the magnet c'ore.

Although thepreferred embodiments of the invention have been described, the scope of, and the breadth of protection af forded to, the invention are limited solely by the appended claims.

I claim:

1. An electromagnetic fuel injection spray valve, including a valve proper, a spray nozzle opened and closed by said valve proper, a disc-shaped armature connected to said valve proper for operating the latter, and wherein the improvement comprises a cylindrical hollow shaft incorporated by said armature, said valve proper being associated with the free end of said shaft, a coil spring in the hollow of said shaft for biasing said valve proper to its closed position, a slider (12) slidable in the hollow of said shaft, and a magnet core, and wherein said coil spring presses on said slider against said core.

2. The injection valve as defined in claim 1, including a cylindrical housing for the fuel injection valve, and wherein said core is within said housing and has the form of alaminated magnet core that is rectangular in cross section, and the four corners of said core touch said housing to center said core inside said housing.

3. The injection valve as defined in claim 2, including a magnet armature, and wherein a face of said armature lies ad jacent to said core and is cone shaped.

4. The injection valve as defined in claim 1, including a housing for the fuel injection valve, and a plurality of bores (l7, 18) for connecting the hollow of said shaft to the interior of said housing.

5. The injection valve as defined in claim 1, including a housing for the fuelinjection valve, and wherein part (2) of said housing guides said armature in its movement and is in direct contact with said core.

6, The injection valve as defined in claim 1, wherein the disc-shaped part of said armature is substantially rectangular and has two straight and two arcuate sides.

7. The injection valve as defined in claim 6, wherein the disc-shaped part of said armature has parallel slots to reduce eddy currents.

8. The injection valve as defined in claim 1, wherein the disc-shaped part of said armature is composed of riveted laminations to reduce eddy currents.

9. The injection valve as defined in claim 1, wherein the disc-shaped part of said armature is made of soft iron and said shaft is made of steel, and further including means for fastening together these two armature parts.

UEQITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent: No. 3 592 392 Dated July 13th 1971 Inventor(s) Robert Huber It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the heading of the patent, line 2, after "Zumikon" insert Switzerland; line 7, delete "l".

Signed and sealed this ll th day of December 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,J'R. ROBERT GOTTSCHALK Attesting Officer Acting Commissioner of Patent;

FCRM F'O-105O 110-69) UscoMM-Dc 60376.:69

9 U 5 GOVERNMENT PI'HNYING OFFICE 19.9 OJ66-334

Claims

2. The injection valve as defined in claim 1, including a cylindrical housing for the fuel injection valve, and wherein said core is within said housing and has the form of a laminated magnet core that is rectangular in cross section, and the four corners of said core touch said housing to center said core inside said housing.

3. The injection valve as defined in claim 2, including a magnet armature, and wherein a face of said armature lies adjacent to said core and is cone shaped.

4. The injection valve as defined in claim 1, including a housing for the fuel injection valve, and a plurality of bores (17, 18) for connecting the hollow of said shaft to the interior of said housing.

5. The injection valve as defined in claim 1, including a housing for the fuel injection valve, and wherein part (2) of said housing guides said armature in its movement and is in direct contact with said core.

6. The injection valve as defined in claim 1, wherein the disc-shaped part of said armature is substantially rectangular and has two straight and two arcuate sides.