FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
FUEL INJECTION VALVE;
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION ORGANISED
AND EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 7-
3, MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 100-8310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.
2
DESCRIPTION
5 Technical Field
[0001]
The present application relates to a fuel injection
valve.
Background Art
10 [0002]
In recent years, there has been a strengthening of
emission regulations relating to an automobile internal
combustion engine and the like, and with regard to a fuel
spray emitted from a fuel injection valve, there is demand
15 for a sufficiently atomized fuel spray, while restricting
an excessive widening of a spray angle with consideration
to adherence to an intake pipe wall face. Further, varied
deliberation is being carried out relating to a method that
utilizes a swirling flow as one fuel spray atomization
20 method.
[0003]
For example, a fuel injection valve that includes a
valve seat and a valve body having an aperture portion
through which a fuel passes from an upstream side, and an
25 injection hole plate that causes a swirling flow to be
3
formed on a downstream side of the valve seat, wherein
radial depressions having a branching portion, an
introduction portion, a cylindrical portion, and a swirling
portion are manufactured on an upstream side of the
5 injection hole plate, an injection hole is manufactured on
a downstream side of the cylindrical portion, and further
atomization of a spray is realized by regulating dimensions
of a passage including the swirling portion, is disclosed
in Patent Literature 1.
10 [0004]
According to Patent Literature 1, a terminating face
of the swirling portion is inclined by an angle θ with
respect to a central axis of the introduction portion, and
by arranging in such a way that the angle θ is within a
15 range of 0° or more, 45° or less, a flow A flowing in
directly from the introduction portion and a flow B flowing
into the cylindrical portion via the swirling portion become
opposed in the cylindrical portion, and when a width of the
introduction portion is W1 and a width of the swirling
20 portion is W2, strengths of the flows A and B are
approximately equal when 0.3 ≤ W2/W1 ≤ 0.7.
[0005]
Because of this, the swirling flow is uniform, and a
thickness of a fuel film formed on an inner wall of the
25 injection hole is uniform, because of which a degree of
4
atomization is good.
[0006]
However, the method disclosed in Patent Literature 1,
whereby atomization is carried out by a fuel film being
5 thinned by a swirling flow, causing the film to disintegrate,
is such that a widening of the film is promoted by increasing
a swirling force, whereby atomization is promoted, but a
spray angle is also considerably increased simultaneously.
[0007]
10 Also, a fuel injection valve wherein a position in
which an injection hole is disposed is adjusted, and the
injection hole is provided with an angle, in order to
realize sufficient atomization while restricting a spray
widening is disclosed in Patent Literature 2. According to
15 the fuel injection valve disclosed in Patent Literature 2,
swirling force strength is regulated in accordance with the
position in which the injection hole is disposed, thereby
restricting a spray widening, simultaneously with which a
decrease in atomization performance can be restricted, or
20 atomization performance can be increased, by increasing a
force with which fuel collides with an inner wall face of
the injection hole by providing the injection hole with an
angle.
Citation List
25 Patent Literature
5
[0008]
Patent Literature 1: International Publication WO
2017/060945, pamphlet
Patent Literature 2: JP-A-2017-210907
5 Summary of Invention
Technical Problem
[0009]
It is disclosed in both Patent Literature 1 and 2 that
a flow flowing directly from an introduction portion into
10 an injection hole and a flow flowing into the injection hole
via a swirling chamber exist. Further, in Patent Literature
1, the flow A, which flows directly into the injection hole
from the introduction portion, and the flow B, which flows
into the injection hole via the swirling chamber, are caused
15 to oppose, and by arranging in such a way that the strengths
of the flows A and B are approximately equal, uniformity of
a film inside the injection hole improves, and atomization
improves. Also, in Patent Literature 2, swirling force is
regulated by adjusting the injection hole position, that is,
20 by adjusting an amount by which the injection hole is offset
from an introduction portion central axis, thereby
restricting a spray widening, simultaneously with which a
decrease in atomization performance can be restricted, or
atomization performance can be increased, by increasing the
25 force with which fuel collides with the inner wall face of
6
the injection hole by providing the injection hole with an
angle.
[0010]
Herein, changing the injection hole offset amount, or
5 changing an injection hole diameter, an injection hole
length, a swirling chamber diameter, an injection hole pitch
diameter, or the like, instead of providing the injection
hole with an angle, are conceivable as spray angle
adjustment methods. However, changing the injection hole
10 diameter, the swirling chamber diameter, or the injection
hole offset amount changes the way in which both of the
flows A and B flow into the injection hole, meaning that
this is a method that involves a significant change in not
only atomization performance but also in an injection flow
15 rate. Consequently, the number of design man-hours needed
to obtain a target spray angle while maintaining a required
flow rate is enormous.
[0011]
Also, changing the injection hole pitch diameter is
20 assumed to be minimal as an advantage of spray angle
adjustment as a layout on an injection hole plate is also
limited due to the size of the fuel injection valve. Other
than this, providing the injection hole with an angle is
such that when considering press molding, which is widely
25 used as an existing injection hole formation method, the
7
injection hole is provided in the swirling chamber, because
of which there is concern that processibility will worsen
considerably with respect to a case in which there is no
injection hole angle, regardless of the processing order of
5 the swirling chamber and the injection hole portion.
[0012]
The present application has been made to solve the
above problem and an object of the present application is
to provide a fuel injection valve such that a spray angle
10 can be adjusted easily while having a sufficient atomization
performance.
Solution to Problem
[0013]
A fuel injection valve disclosed in the present
15 application is a fuel injection valve having a valve body
that opens and closes a valve seat, wherein a fuel passes
between the valve body and a valve seat seat portion, and
is subsequently injected from a multiple of injection holes
provided in an injection hole plate mounted on a downstream
20 side end face of the valve seat, and wherein a swirling
chamber, a multiple of which are disposed on a radial
direction outer side of an aperture portion of the valve
seat, a central portion communicating with the aperture
portion, an introduction portion that guides a flow of the
25 fuel from the central portion to the swirling chamber, and
8
the injection hole, which is opened in the swirling chamber
and injects the fuel to an exterior, are included in an
upstream side end face of the injection hole plate, a
central axis of the introduction portion and a center of
5 the injection hole are caused to be offset, and centers of
the swirling chamber and the injection hole are caused to
coincide, and when, of side walls of the introduction
portion, a side wall on a side to which the center of the
injection hole is offset is a first side wall and a side
10 wall on an opposite side is a second side wall, an end face
is provided between the swirling chamber and the first side
wall, and an angle θ1 formed by the end face and the central
axis of the introduction portion is configured in such a
way that θ1 < 90°.
15 Advantageous Effects of Invention
[0014]
A fuel injection valve disclosed in the present
application can provide a fuel injection valve such that a
spray angle can be adjusted easily while having a sufficient
20 atomization performance.
Brief Description of Drawings
[0015]
[Fig. 1] Fig. 1 is a drawing showing a cross-section
of a fuel injection valve according to a first embodiment.
25 [Fig. 2] Fig. 2 is a drawing showing a cross-section
9
of a valve body leading end portion, a valve seat, and an
injection hole plate of the fuel injection valve according
to the first embodiment.
[Fig. 3] Fig. 3 is a plan view of the injection hole
5 plate of the fuel injection valve according to the first
embodiment seen from a direction of an A-A line of Fig. 2.
[Fig. 4] Fig. 4 is a drawing showing an introduction
portion of the injection hole plate and a flow of fuel in
the fuel injection valve according to the first embodiment.
10 [Fig. 5] Fig. 5 is a drawing showing another example
of an introduction portion of the injection hole plate and
a flow of fuel in the fuel injection valve according to the
first embodiment.
[Fig. 6] Fig. 6 is a drawing showing an introduction
15 portion of an injection hole plate and a flow of fuel in a
fuel injection valve according to a second embodiment.
[Fig. 7] Fig. 7 is a drawing showing another example
of an introduction portion of the injection hole plate and
a flow of fuel in the fuel injection valve according to the
20 second embodiment.
[Fig. 8] Fig. 8 is a drawing illustrating an advantage
of the fuel injection valve shown in Fig. 7.
Description of Embodiments
[0016]
25 Hereafter, preferred embodiments of a fuel injection
10
valve according to the present application will be described
using the drawings. In the drawings, identical reference
signs are allotted to identical or similar components, and
sizes or scales of corresponding constituent members are
5 independent. Also, although a fuel injection valve
configuration actually includes a further multiple of
members, only portions necessary for the description are
mentioned, and other portions are omitted, in order to
facilitate the description.
10 [0017]
First Embodiment
Fig. 1 is a drawing showing a cross-section of a fuel
injection valve according to a first embodiment.
In Fig. 1, a fuel injection valve 100 supplies fuel
15 to an internal combustion engine utilized as an engine of,
for example, an automobile. The fuel injection valve 100
includes a drive circuit 1, a solenoid device 2, a housing
3, which is a yoke portion of a magnetic circuit, a core 4,
which is a fixed core portion of the magnetic circuit, a
20 coil 5 provided on an outer periphery of the core 4, an
armature 6, which is a movable core portion of the magnetic
circuit, and a valve device 7. The valve device 7 is
configured of a valve body 8, a valve holder 9, and a valve
seat 10.
25 [0018]
11
The valve holder 9 is press-fitted into an outer
diameter portion of the core 4 and subsequently welded, and
the armature 6 is press-fitted into the valve body 8 and
subsequently welded. An injection hole plate 11 is mounted
5 on a downstream side end face of the valve seat 10, that is,
a downstream side valve seat aperture portion, by being
joined using a welded portion 12, and is mounted in an
interior of the valve holder 9 as an integrated structure.
An injection hole 13 (refer to Fig. 2) penetrating in a
10 plate thickness direction is provided in the injection hole
plate 11, as described hereafter.
[0019]
Next, an operation of the fuel injection valve 100
shown in Fig. will be described.
15 On an actuating signal being sent to the drive circuit
1 of the fuel injection valve 100 from an internal
combustion engine control device, the coil 5 of the fuel
injection valve 100 is energized by a current, a magnetic
flux is generated in the magnetic circuit configured of the
20 armature 6, the core 4, the housing 3, and the valve holder
9, the armature 6 is suctioned to act in the direction of
the core 4, and the valve body 8, which forms an integrated
structure with the armature 6, separates from a valve seat
seat portion 10a, whereby a gap is formed. Because of this,
25 fuel passes through the gap between the valve seat seat
12
portion 10a and the valve body 8 from a chamfered portion
14a of a ball 14 welded to a leading end portion of the
valve body 8, and is injected from the injection hole 13
into an intake port of the internal combustion engine.
5 [0020]
On an operation stopping signal being sent to the
drive circuit 1 of the fuel injection valve 100 from the
internal combustion engine control device, the energization
by the current of the coil 5 of the fuel injection valve
10 100 stops, the magnetic flux in the magnetic circuit
decreases, the gap between the valve body 8 and the valve
seat seat portion 10a reaches a closed state owing to a
compression spring 15 that is pressing the valve body 8 in
a valve closing direction, and the fuel injection ends. The
15 valve body 8 slides along a guide portion of the valve
holder 9 with a sliding portion 6a of the armature 6, and
when the valve is in an opened state, an upper face 6b of
the armature 6 is in contact with a lower face of the core
4.
20 [0021]
Fig. 2 is a drawing showing a cross-section of the
ball 14 welded to the leading end portion of the valve body
8 of the fuel injection valve 100, the valve seat 10, and
the injection hole plate 11, and Fig. 3 is a plan view of
25 the injection hole plate 11 of the fuel injection valve 100
13
seen from a direction of an A-A line of Fig. 2.
In order to realize atomization of fuel by a swirling
flow, a central portion 11a that communicates with an
aperture portion 10b of the valve seat 10, a groove form
5 introduction portion 11b, and a multiple of swirling
chambers 11c including the injection hole 13 are included
in an upstream side end face of the injection hole plate 11,
and the multiple of swirling chambers 11c are disposed in
such a way as to be caused to communicate with each other,
10 as shown in Fig. 2 and Fig. 3. Herein, a center of each
injection hole 13 is provided in a position caused to be
offset with respect to a center of the introduction portion
11b.
[0022]
15 According to the heretofore described configuration,
fuel that has flowed into the swirling chamber 11c flows
into the injection hole 13 while generating a swirling flow,
and by the swirling flow also being maintained in an
interior of the injection hole 13, a thin film following an
20 inner wall of the injection hole 13 is formed, and the
configuration is such that fuel atomization is promoted by
the thin film being injected from the injection hole 13 in
a hollow conical form.
[0023]
25 Fig. 4 is a drawing showing the introduction portion
14
11b of the injection hole plate 11 and a flow of fuel in
the fuel injection valve 100.
In Fig. 4, the injection hole plate 11 is such that
when, of side walls of the introduction portion 11b, a side
5 to which the center of the injection hole 13 is offset is a
first side wall W1 and an opposite side is a second side
wall W2, a linear end face L is provided between the swirling
chamber 11c and the first side wall W1, and an angle θ1
formed by the end face L and a central axis of the
10 introduction portion 11b is configured in such a way that
θ1 < 90°. As shown in Fig. 4, the end face L and the first
side wall W1 are connected at a first connection point a,
and the swirling chamber 11c and the end face L are connected
at a second connection point b.
15 [0024]
Adopting this kind of form for the injection hole
plate 11 means that when considering a spray angle reduction
because of concern about a fuel spray adhering to an intake
pipe, a diameter of the injection hole 13, a diameter of
20 the swirling chamber 11c, an amount by which the injection
hole 13 is offset, and the like, which are factors in a
swirling force changing considerably, are not changed,
because of which an effect on the flow A, which flows
directly into the injection hole 13, is minimal, and by
25 adjusting the direction in which the flow B, which passes
15
through the swirling chamber 11c, flows into the injection
hole 13, a spray injection direction can be adjusted.
Consequently, the spray angle can be adjusted while
minimizing an effect on an injection flow rate or an
5 atomization performance. Also, as spray angle adjustment
can be carried out by only adjusting the angle of the end
face L, without changing a parameter such as the diameter
of the swirling chamber 11c or the amount by which the
injection hole 13 is offset, spray angle adjustment man10 hours can be reduced with respect to an existing method.
[0025]
Furthermore, by the first connection point a or the
second connection point b, or both thereof, being configured
of smooth curved form portions Ra and Rb, as shown in Fig.
15 5, a decrease in a fuel cavity capacity, a decrease in
pressure loss of the flow B at the second connection point
b, and a detachment of fuel in the flow A at the first
connection point a are restricted, fuel spray atomization
is promoted, and a flow rate change caused by a change in
20 temperature or atmosphere is restricted.
[0026]
As heretofore described, the fuel injection valve 100
according to the first embodiment is such that when, of the
side walls of the introduction portion 11b, the side to
25 which the center of the injection hole 13 is offset is the
16
first side wall W1 and the opposite side is the second side
wall W2, the linear end face L connecting the swirling
chamber 11c and the first side wall W1 is provided, and the
angle θ1 formed by the end face L and the central axis of
5 the introduction portion 11b is configured in such a way
that θ1 < 90°.
[0027]
Configuring in this way means that when considering a
spray angle reduction because of concern about the fuel
10 spray adhering to the intake pipe, the diameter of the
injection hole 13, the diameter of the swirling chamber 11c,
the amount by which the injection hole 13 is offset, and
the like, which are factors in the swirling force changing
considerably, are not changed, because of which the effect
15 on the flow A, which flows directly into the injection hole
13, is minimal, and by adjusting the direction in which the
flow B, which passes through the swirling chamber 11c, flows
into the injection hole 13, the spray injection direction
can be adjusted.
20 [0028]
Consequently, the spray angle can be adjusted while
minimizing the effect on the injection flow rate or the
atomization performance. Also, as the spray angle
adjustment can be carried out by only adjusting the angle
25 of the end face L, without changing a parameter such as the
17
diameter of the swirling chamber 11c or the amount by which
the injection hole 13 is offset, spray angle adjustment manhours can be reduced with respect to an existing method.
[0029]
5 Also, the first connection point a or the second
connection point b, or both thereof, are configured of the
smooth curved form portions Ra and Rb. Herein, fuel
detachment is an item that affects atomization due to a
fluid pressure loss in the detached portion, or affects flow
10 rate change with respect to a change in temperature or
atmosphere, and is a phenomenon that should be restricted
as far as possible in an introduction portion.
[0030]
In consideration of the above, a detachment of fuel
15 in the flow A at the first connection point a is restricted
by the first connection point a being configured of the
curved form portion Ra, because of which fuel spray
atomization is promoted, and a flow rate change caused by a
change in temperature or atmosphere is restricted.
20 [0031]
Also, an overall capacity of a fuel cavity enclosed
by the leading end portion of the valve body 8, the valve
seat 10, and the injection hole plate 11 is also a factor
that considerably affects a flow rate change (a dynamic flow
25 rate) when there is a change in temperature or atmosphere.
18
That is, when injecting into a negative pressure atmosphere,
one portion of fuel in the fuel cavity is sucked out from
the injection hole 13 into the engine intake pipe by the
negative pressure after valve closure is completed, and a
5 flow rate change increases. As a flow speed of the fuel
sucked out from inside the fuel cavity is low, fuel whose
particle diameter is inferior is injected immediately after
valve closure. This means that when considering forms of
the valve seat 10 and the injection hole plate 11, taking
10 the fuel cavity capacity into consideration is one of the
important factors in improving various characteristics of
the fuel injection valve 100.
[0032]
In consideration of the above, fuel spray atomization
15 is promoted, and a flow rate change caused by a change in
temperature or atmosphere is restricted, by the second
connection point b being configured of the curved form
portion Rb, and the capacity of the introduction portion
11b in the swirling chamber 11c being even slightly reduced.
20 [0033]
Also, when the flow B, which has flowed through the
swirling chamber 11c, reaches the end face L, the flow B
shifts smoothly to the θ1 direction owing to the curved form
portion Rb, whereby pressure loss of the flow B is reduced,
25 and the atomization performance improves. Furthermore,
19
processibility of the introduction portion 11b improves
owing to the first connection point a and the second
connection point b being configured of the curved form
portions Ra and Rb respectively, and when the introduction
5 portion 11b is formed by a pressing process, an increase in
die durability can also be expected.
[0034]
Second Embodiment
Next, a fuel injection valve according to a second
10 embodiment will be described.
Fig. 6 is a drawing showing an introduction portion
of an injection hole plate and a flow of fuel in the fuel
injection valve according to the second embodiment.
The fuel injection valve 100 according to the second
15 embodiment is such that a linear wall face S circumscribing
the swirling chamber 11c exists between the swirling chamber
11c and the linear end face L, as shown in Fig. 6, and the
wall face S and the end face L are connected by a smooth
curved form portion Rc. Other configurations are the same
20 as in the first embodiment, and are omitted from the drawing.
The fuel injection valve 100 according to the second
embodiment with the heretofore described configuration is
such that, not being limited to the diameter of the swirling
chamber 11c, a length of the end face L can also be adjusted,
25 and an adjustment of a component of the flow B in the θ1
20
direction, that is, a spray angle adjustment, can be carried
out. In order to cause the direction of the flow B to
change smoothly from the wall face S to the end face L at
this time, a third connection point c of the wall face S
5 and the end face L is configured of the smooth curved form
portion Rc.
[0035]
As heretofore described, the fuel injection valve 100
according to the second embodiment is such that a layout
10 flexibility of the end face L improves owing to the
existence of the wall face S, and spray angle adjustment
can be carried out still more easily.
[0036]
Also, as shown in Fig. 7, a minimal gap portion E
15 between a side wall face that extends to the first
connection point a or the curved form portion Ra (the curved
form portion Ra is shown in Fig. 7) from the swirling chamber
11c via the end face L and a center M of the injection hole
13 is of a form within a range of a virtual swirling chamber
20 circle Vs formed by extending an arc of the swirling chamber
11c, whereby a tributary As that separates from the flow A
and heads to a side of the swirling chamber 11c, as shown
in Fig. 8, can be effectively restricted, a pressure loss
caused by a collision between the tributary As and the flow
25 B is reduced, and fuel spray atomization is promoted. Also,
21
an advantage of pressure loss reduction obtained by
restricting a length of an introduction portion of the flow
B is promoted, fuel spray atomization is further promoted
by restricting swirling chamber capacity, and a flow rate
5 change caused by a change in temperature or atmosphere is
restricted. Herein, a case wherein the tributary As and
the flow B collide is shown in Fig. 8.
[0037]
Furthermore, by adopting a form wherein a linear
10 distance between a point P on a side wall face from the
swirling chamber 11c to the first connection point a or the
curved form portion Ra via the end face L, at which a
distance from an injection hole portion center is greatest,
and the center of the injection hole 13 is two times or less
15 greater than a radius of the swirling chamber 11c, the
advantage of pressure loss reduction obtained by restricting
the length of the introduction portion of the flow B is
promoted, fuel spray atomization is further promoted by
restricting the swirling chamber capacity, and a flow rate
20 change when there is a change in temperature or atmosphere
is restricted.
[0038]
As heretofore described, the fuel injection valve 100
according to the second embodiment is configured in a form
25 wherein the linear wall face S circumscribing the swirling
22
chamber 11c exists between the swirling chamber 11c and the
linear end face L.
This means that, not being limited to the diameter of
the swirling chamber 11c, the length of the end face L can
5 also be adjusted, and an adjustment of a θ1 direction
component of the flow B, that is, a spray angle adjustment,
can be carried out.
[0039]
In order to cause the direction of the flow B to change
10 smoothly from the wall face S to the end face L at this
time, the smooth curved form portion Rc is provided as the
third connection point c of the wall face S and the end face
L. By the curved form portion Rc being provided, the
processibility of the introduction portion 11b improves,
15 and when the introduction portion 11b is formed by a
pressing process, an increase in die durability can also be
expected. In this way, the layout flexibility of the end
face L improves owing to the existence of the wall face S,
and spray angle adjustment can be carried out still more
20 easily.
[0040]
Also, the minimal gap portion E between the side wall
face that extends to the first connection point a, or the
curved form portion Ra that configures the first connection
25 point a in a curved line, from the swirling chamber 11c via
23
the end face L and the injection hole 13 is of a form within
a range of the virtual swirling chamber circle Vs formed by
extending an arc of the swirling chamber 11c.
This means that, as opposed to a case wherein the
5 minimal gap portion E is outside the range of the virtual
swirling chamber circle Vs, the tributary As that separates
from the flow A and heads to a side of the swirling chamber
11c can be effectively restricted, a pressure loss caused
by a collision between the tributary As and the flow B is
10 reduced, and fuel spray atomization is promoted. Also, fuel
spray atomization is further promoted, and a flow rate
change caused by a change in temperature or atmosphere is
restricted, by the advantage of pressure loss reduction
obtained by restricting the length of the introduction
15 portion of the flow B, or by restricting the swirling
chamber capacity.
[0041]
Also, the linear distance between the point P on the
side wall face from the swirling chamber 11c to the first
20 connection point a, or the curved form portion Ra that
configures the first connection point a in a curved line,
via the end face L, at which the distance from the center
of the injection hole 13 is greatest, and the center of the
injection hole 13 is two times or less greater than the
25 radius of the swirling chamber 11c.
24
Because of this, fuel spray atomization is further
promoted, and a flow rate change caused by a change in
temperature or atmosphere is restricted, by the advantage
of pressure loss reduction obtained by restricting the
5 length of the introduction portion of the flow B, or by
restricting the swirling chamber capacity.
[0042]
Although the present application is described above
in terms of various exemplary embodiments and
10 implementations, it should be understood that the various
features, aspects, and functionality described in one or
more of the individual embodiments are not limited in their
applicability to the particular embodiment with which they
are described, but instead can be applied, alone or in
15 various combinations to one or more other embodiments.
It is therefore understood that numerous modifications
which have not been exemplified can be devised without
departing from the scope of the present application. For
example, at least one of the constituent components may be
20 modified, added, or eliminated. At least one of the
constituent components mentioned in at least one of the
preferred embodiments may be selected and combined with the
constituent components mentioned in another preferred
embodiment.
25 Reference Signs List
25
[0043]
1 drive circuit, 2 solenoid device, 3 housing, 4 core, 5
coil, 6 armature, 6a sliding portion, 6b upper face, 7 valve
device, 8 valve body, 9 valve holder, 10 valve seat, 10a
5 valve seat seat portion, 10b aperture portion, 11 injection
hole plate, 11a central portion, 11b introduction portion,
11c swirling chamber, 12 welded portion, 13 injection hole,
14 ball, 14a chamfered portion, 15 compression spring, 100
fuel injection valve, W1 first side wall, W2 second side
10 wall, L end face, a first connection point, b second
connection point, c third connection point, A, B flow, Ra,
Rb, Rc curved form portion, S wall face, M center, E minimal
gap portion, Vs virtual swirling chamber circle, As
tributary.
15
26
We Claim :
[Claim 1]
A fuel injection valve comprising a valve body that
opens and closes a valve seat, wherein a fuel passes between
5 the valve body and a valve seat seat portion, and is
subsequently injected from a multiple of injection holes
provided in an injection hole plate mounted on a downstream
side end face of the valve seat, and wherein
a swirling chamber, a multiple of which are disposed
10 on a radial direction outer side of an aperture portion of
the valve seat, a central portion communicating with the
aperture portion, an introduction portion that guides a flow
of the fuel from the central portion to the swirling chamber,
and the injection hole, which is opened in the swirling
15 chamber and injects the fuel to an exterior, are included
in an upstream side end face of the injection hole plate,
a central axis of the introduction portion and a
center of the injection hole are caused to be offset, and a
center of the swirling chamber and the center of the
20 injection hole are caused to coincide, and
when, of side walls of the introduction portion, a
side wall on a side to which the center of the injection
hole is offset is a first side wall and a side wall on an
opposite side is a second side wall, an end face is provided
25 between the swirling chamber and the first side wall, and
27
an angle θ1 formed by the end face and the central axis of
the introduction portion is configured in such a way that
θ1 < 90°.
[Claim 2]
5 The fuel injection valve according to claim 1, wherein,
when a connection point of the end face and the first side
wall is a first connection point and a connection point of
the swirling chamber and the end face is a second connection
point, either one or both of the first connection point and
10 the second connection point are configured of a smooth
curved form portion.
[Claim 3]
The fuel injection valve according to claim 2, wherein
a minimal gap portion between a side wall face extending to
15 the first connection point or the curved form portion from
the swirling chamber via the end face and a center of the
injection hole is within a range of a virtual swirling
chamber circle formed by extending an arc of the swirling
chamber (11c).
20 [Claim 4]
A fuel injection valve comprising a valve body that
opens and closes a valve seat, wherein a fuel passes between
the valve body and a valve seat seat portion, and is
subsequently injected from a multiple of injection holes
25 provided in an injection hole plate mounted on a downstream
28
side end face of the valve seat, and wherein
a swirling chamber, a multiple of which are disposed
on a radial direction outer side of an aperture portion of
the valve seat, a central portion communicating with the
5 aperture portion, an introduction portion that guides a flow
of the fuel from the central portion to the swirling chamber,
and the injection hole, which is opened in the swirling
chamber and injects the fuel to an exterior, are included
in an upstream side end face of the injection hole plate,
10 a center of the injection hole is caused to be offset
with respect to a central axis of the introduction portion,
and a center of the swirling chamber and the center of the
injection hole are caused to coincide, and
when, of side walls of the introduction portion, a
15 side wall on a side to which the center of the injection
hole is offset is a first side wall and a side wall on an
opposite side is a second side wall, an end face is provided
between the swirling chamber and the first side wall, a wall
face circumscribing the swirling chamber is formed between
20 the swirling chamber and the end face, and the wall face
and the end face are connected by a smooth curved form
portion.
[Claim 5]
The fuel injection valve according to claim 4, wherein
25 an angle θ1 formed by the end face and the central axis of
29
the introduction portion is configured in such a way that
θ1 < 90°.
[Claim 6]
The fuel injection valve according to claim 4 or 5,
5 wherein a minimal gap portion between a side wall face
extending to a connection point of the end face and the
first side wall, or the curved form portion, from the
swirling chamber via the end face and the center of the
injection hole is within a range of a virtual swirling
10 chamber circle formed by extending an arc of the swirling
chamber.
[Claim 7]
The fuel injection valve according to claim 3 or 6,
wherein a linear distance between a point on the side wall
15 face at which a distance from the center of the injection
hole is at a maximum and the center of the injection hole
is two times or less greater than a radius of the swirling
chamber.