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Патент USA US3074662

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Jan. 22, 1963
J. F. ARMSTRONG
3,074,652
FUEL INJECTION SYSTEM
‘Original. Filed March 2, 1959
FIG.I.
27_
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JAMES FRED ARMSTRONG
AGENT
ice ,
3,074,652
Patented Jan. 22, 1963
2
> nozzle tube is a combination nozzle tip and valve seat
3,074,652
member 159.
FUEL INJECTION SYSTEM
7
James F. Armstrong, St. Louis, Mo., assignor to ACF
Industries, Incorporated, New York, N.Y., a corpora
This comprises a short tube having an
annular external flange 161 which is press ?tted into the
inturned ?ange 163 at the outer (lower) end of the nozzle
tube
155. The outer end of tip 159 is cut 011 at an angle
tion of New Jersey
as indicated“ at 165. The inner end portion of the tip
Original application Mar. 2, 1959, Ser. No. 796,605.
159 extends inward from ?ange 161 and provides a nee
Divided and this application May 16, 1961, Ser. No.
dle seat 167.
110,505
Each nozzle N includes the needle 27 having its inner
1 Claim. (Cl. 239-533)
10 (upper) end attached to the diaphragm 135, the needle
This invention relates to fuel injection systems for in
extending slidably in the nozzle tube 155. The diameter
ternal combustion engines, and more particularly to con
of the needle is less than the internal diameter of the noz
tinuous ?ow systems of this class adapted for port in
zle tube, to provide an annular space around the needle
jection, in which the fuel is pressurized, measured under
for flow of fuel through the tube to tip 159, and the
pressure in accordance with engine requirements, and dis 15 needle is held centered in the tube by upper and lower
tributed under pressure to points adjacent the intake valves
radial projections 169 on the needle which slide on the
of the several cylinders or combustion chambers of the
internal surface of the nozzle tube. At its outer (lower)
engine.
end, the needle has an enlarged portion 171. This por
An object of the invention is the provision of an im
tion has a conically concave face 173 at its outer end.
proved fuel injection nozzle construction, adapted for 20 It also has an axial passage 175 leading inward from
tightly sealing against leakage of fuel when closed, hav
the face and a passage 177 extending radially outward
ing a long life, and adapted to prevent the formation of
from the upper end of passage 175. Seated against face
droplets at a low rate of fuel flow (as when the engine
173 is a piece of wire mesh 179, and seated against the
is idling), and which is economical to manufacture.
wire mesh is a disk 181 of fuel-resistant rubber or the like.
25
In the accompanying drawings,
The wire mesh 179 and rubber disk 181 are held against
FIG. 1 is a plan view of an engine intake manifold,
the face 173 by a cap 183 press ?tted on the needle en
showing an arrangement of fuel injection nozzles.
largement 171. The cap has an opening 185 for receiv
FIG. 2 is a vertical section taken on line 2-2 of
ing the inner end portion 167 of nozzle tip 159. The cap
FIG. 1;
terminates short of the radial passage 177, this passage
FIG. 3 is an enlarged vertical section of a nozzle in 30 and passage 175 being provided to vent air from under
accordance with the invention and taken on line 3—3
the disk 181 in the assembly of the wire mesh, disk and
of FIG. 1;
cap on the needle enlargement 171. The rubber disk 181
PEG. 4 is a greatly enlarged fragment of FIG. 3.
is initially a flat disk held in a bowed condition under
This application is a division of my application Serial
compression against the face 173 by the cap 183, which
Number 796,605, ?led March 2, 1959, Patent No. 35 places the lower working surface under compression to
constitute a resilient tip for the needle engageable with
As appears in FIG. 1, the fuel injector nozzles N are
the inner end 167 of the nozzle tip (which constitutes a
2,985,160.
clustered in groups of two, so that, as a matter of prac
tice, there are four nozzle clusters on the intake mani
w»?
seat for the needle) to provide a tight seal to prevent
leakage when the needle is closed. The rubber face of
fold M of the engine. As shown, each nozzle cluster 40 the valve, being compressed, resists the shearing forces
of seat engagement. The screen is used to provide for
comprises a body 131 (FIG. 3) formed to provide two
some slight swelling of the rubber composition between
the interstices thereof. With the arrangement shown,
135 is clamped on the body by a head 137. This head
when the needle is retracted and the rubber disk is clear
45
is similarly formed to provide two shallow circular re
of the seat 167, fuel ?ows upward around the seat 167,
cesses 139 located side-by-side, which mate with recesses
and thence around into the nozzle tip and down and out
of the nozzle tip. This tends to avoid the formation of
133. Again, only one of these recesses 139 appears in
droplets at low rates of ?ow as during engine idling which
FIG. 3. As to each nozzle N, recess 133 constitutes a
charging fuel chamber and recess 139 constitutes a datum 50 would cause engine idle roughness.
As to each nozzle N, the needle 27 is biased downward
pressure chamber. The head 137 has an internally re
by a spring 187 toward its closed position wherein the
cessed rib 141 extending lengthwise thereof. This pro
shallow circular recesses 133 located side-by-side.
one of these recesses appears in FIG. 3.
Only
A diaphragm
vides a passage 143 connecting the two datum pressure
chambers of the cluster. Fuel connections may be made
between the ends of these ribs to provide for the inter
connection of the datum pressure chambers of all the noz
zles N in the system. FIG. 1 shows interconnections at
145 between the forward and rearward clusters of each
bank of four cylinders of the engine. The body 131 and
head 137 are formed with bolt holes 147 for the recep
tion of bolts for attaching them to the manifold M.
For each of the two nozzles N in a cluster, the base
131 of the cluster has an outwardly (downwardly) pro
jecting tubular boss 14-9 coaxial with the recesses or cham
bers 133, 139. The hole through this boss is enlarged
at its inner end providing a recess 151 and an inwardly
facing annular shoulder 153. Each nozzle N comprises
a nozzle tube 155 threaded in the hole in the boss and
projecting out (downward) from the boss. The nozzle
tube has a head 157 at its inner (upper) end received in
the recess 151 and seating against shoulder 153 for seal
ing purposes.
rubber disk 181 at the lower end of the needle engages
the needle seat 167. For each nozzle, there is a passage
55 189 through the base and the head communicating with
the lower recess or chamber 133. To this passage is con
nected the respective fuel delivery line 25. According
ly, the needle 27 is subject to the downward force of
spring 187 and datum pressure in recess or chamber 139
60 tending to drive it downward and close it, and an upward
force due to charging fuel pressure in the lower recess
or chamber 133 tending to drive it upward and open it.
The charging pressure being suf?cient to overcome the
force of the spring 187 and the datum pressure, diaphragm
65 135 is moved upward to unseat the needle 27 from needle
seat 167 for flow of fuel from chamber 133 out of the
nozzle. Upon an increase in datum pressure, diaphragm
135 ?exes downward to move the needle 27 closer to its
seat 167, thereby to increase the back pressure in the
70 nozzle charging fuel chamber 133, and vice versa.
I claim:
A nozzle for a fuel injection system, said nozzle com
Fixed in the outer (lower) end of the
3,074,652
4
3
means holding said resilient member against said con
cave face, and a wire mesh between said resilient member
and said concave face, said other needle valve end formed
prising a housing, a diaphragm within said housing and
forming therewith opposed expansible chambers, a tube
having one end attached to said housing and extending
from one of said chambers, a needle valve slidably mount
ed within said tube and attached at one end to said dia
with an air vent passage extending from said concave
5
phragm, a nozzle tip at the other end of said tube hav
ing a tubular portion extending inwardly within said tube
and forming a- valve seat, a resilient member ?xed t0
the other end of said needle valve adjacent to said valve
seat, said resilient member being formed with a con 10
cave surface facing said valve seat, means ?xed to said
needle valve and retaining said resilient member with
said concave surface under compression, said other needle
valve end formed with a concave face, said retaining
face into said tube.
References Cited in the ?le of this patent
UNITED STATES PATENTS
2,255,203
Wiegand _____________ .._ Sept. 9, 1941
2,857,203
2,904,264
2,957,631
Korte _______________ __ Oct. 21, 1958
Klaber ______________ __ Sept. 15, 1959
Armstrong __________ __ Oct. 25, 1960
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