U.S. patent number 3,592,392 [Application Number 04/836,106] was granted by the patent office on 1971-07-13 for electromagnetic fuel injection spray valve.
This patent grant is currently assigned to Societe des Procedes Modernes d'Injection "-SOPROMI". Invention is credited to Robert Huber.
United States Patent |
3,592,392 |
Huber |
July 13, 1971 |
**Please see images for:
( Certificate of Correction ) ** |
ELECTROMAGNETIC FUEL INJECTION SPRAY VALVE
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.
Inventors: |
Huber; Robert (Zumikon,
C) |
Assignee: |
Societe des Procedes Modernes
d'Injection "-SOPROMI" (Les Mureaux, FR)
|
Family
ID: |
25703683 |
Appl.
No.: |
04/836,106 |
Filed: |
June 24, 1969 |
Current U.S.
Class: |
239/585.2;
310/29; 137/487.5 |
Current CPC
Class: |
H01F
7/1638 (20130101); F02M 51/0614 (20130101); F02M
51/0625 (20130101); F02M 51/0657 (20130101); F02M
51/0635 (20130101); F16K 31/0655 (20130101); F02M
51/08 (20190201); Y10T 137/7761 (20150401); H01F
2007/1676 (20130101) |
Current International
Class: |
F16K
31/06 (20060101); H01F 7/16 (20060101); H01F
7/08 (20060101); F02M 51/06 (20060101); F02M
51/08 (20060101); B05b 001/30 () |
Field of
Search: |
;239/583,584,585 ;123/32
;137/487.5 ;310/15,29 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wood, Jr.; M. Henson
Assistant Examiner: Mar; Michael Y.
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 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.
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.
Description
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.,
by an 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 the induction pipes
of the engine, for example.
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 20 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 combination
with a disc-shaped armature ensures a strong magnetic force and the
greatest possible independence from outside influences.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described, with reference to the FIGS. of the
accompanying drawings, wherein:
FIG. 1 is a longitudinal section of one embodiment;
FIG. 2 is a view taken along line II-II of FIG. 1;
FIG. 3 is a view taken along line III-III 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. 5 is a view taken along line V-V of FIG. 4;
FIG. 6 is a longitudinal section of another modified armature;
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.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The fuel injection spray valve shown in FIG. 1 has a housing
comprising two parts 1 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 1 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 7a is 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 housing part 1, the fuel
under about 20 atmospheres pressure entering the interior of the
housing 1 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 is raised from its seat 9. To
equalize the pressure, other bores 17 and 18 connect the hollow of
the shaft 7a with the interior of the housing 1 and 2. The magnet
armature 7, with its shaft 7a, is so fitted in the housing 1 and 2
that it is raised about 0.1 to 0.2 mm. whenever the magnet coil 3
is energized. A threaded ring 19 presses 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 dimensioning the slider 12, for
example. The stroke of the armature 7 is determinal by the
dimensions of the housing part 2 and of the armature with the
spacer 13.
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 armature rises.
In the embodiment shown in FIGS. 4 and 5, the housing upper part 1
with the core 5 and coil 3 is substantially similar to the
embodiment shown in FIGS. 1 to 3; but the housing lower part 2 is
pressed or squeezed into the upper part 1. A separate spacer 21 is
arranged between the core 5 and the housing part 2; the spacer 21
tangentially guides the armature 7 in its throw, and the thickness
of this spacer adjusts the armature's stroke. In this embodiment,
the armature 7 is still disc-shaped but no longer circular in
outline; instead two opposite 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
includes the 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. This manner 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 the disc-shaped armature 7
is made of soft iron and cemented or welded to the shaft 7a. The
interior of the shaft 7a houses the compression spring 11, which
presses against an intermediate ring pressing against the slider
12, which contacts the magnet core.
Although the preferred embodiments of the invention have been
described, the scope of, and the breadth of protection afforded to,
the invention are limited solely by the appended claims.
* * * * *