JP3715253B2 - Fuel injection valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a fuel injection valve mainly used in a fuel supply system of an internal combustion engine, and in particular,valveA lateral direction communicating with the downstream end of the valve seat between a valve seat member whose downstream end of the valve seat cooperating with the body opens on the front end surface and an injector plate joined to the front end surface of the valve seat member A fuel injection valve having a passage and a swirl chamber in which the downstream end of the lateral passage opens in a tangential direction, and a fuel injection hole for injecting the swirled fuel in the swirl chamber is formed in the injector plate Regarding improvements.
[0002]
[Prior art]
  Such a fuel injection valve is already known as disclosed in, for example, Japanese Patent No. 2659789.
[0003]
[Problems to be solved by the invention]
  Such a fuel injection valve promotes atomization of the fuel by imparting a swirl to the fuel injected from the fuel injection hole. In the conventional fuel injection valve, the fuel injection hole of the injector plate is used. Is placed in the center of the swirl chamber, so that the fuel that has entered the swirl chamber from the lateral passage will swirl the swirl chamber several times before being injected from the fuel hole of the injector plate. The speed loss of the fuel in the swirl chamber is large, and not only does the acceleration of atomization of the fuel after the injection decrease, but also there is a drawback of causing a fuel injection delay.
[0004]
  The present invention has been made in view of such circumstances, and provides the fuel injection valve that effectively promotes atomization of fuel after injection and improves the fuel injection response. With the goal.
[0005]
[Means for Solving the Problems]
  In order to achieve the above object, the present invention provides:valveA lateral direction communicating with the downstream end of the valve seat between a valve seat member whose downstream end of the valve seat cooperating with the body opens on the front end surface and an injector plate joined to the front end surface of the valve seat member A fuel injection valve having a passage and a swirl chamber in which the downstream end of the lateral passage opens in a tangential direction, and a fuel injection hole for injecting the swirled fuel in the swirl chamber is formed in the injector plate The first feature is that the fuel injection hole is arranged with a predetermined distance offset from the center of the swirl chamber to the upstream end side of the lateral passage.
[0006]
  According to the first feature, most of the fuel that has flowed into the swirl chamber from the lateral passage is injected from the fuel injection hole during approximately one rotation of the swirl chamber, and is formed by the injected fuel. By maintaining the high swirl speed of the fuel spray foam, the atomization of the fuel can be effectively promoted, the responsiveness of the fuel injection can be improved, the engine startability and the output performance are improved, and This can contribute to a reduction in fuel consumption.
[0007]
  According to the present invention, in addition to the first feature, the curvature of the inner peripheral surface of the swirl chamberUpstream of the swirl applied to the fuel in the direction along the inner peripheral surfaceFrom the sidedownstreamThe second feature is that the distance is increased toward the side.
[0008]
  According to the second feature, as the fuel that has entered the swirl chamber from the lateral passage advances turning along the inner peripheral surface of the chamber, the turning force is strengthened and generated from the fuel injection hole. By increasing the swirl speed of the fuel spray foam, atomization of the fuel can be promoted more effectively. Furthermore, in addition to the second feature, the third feature of the present invention is that the inner peripheral surface of the swirl chamber is formed along an involute curve having a base circle in the chamber.
[0009]
  According to the third feature, as the fuel that has entered the swirl chamber from the lateral passage advances turning along the inner peripheral surface of the chamber, the turning force can be continuously and smoothly enhanced. And can provide a high swirl speed to the fuel spray foam, which can greatly contribute to the promotion of fuel atomization. Furthermore, in addition to the third feature of the present invention, the fourth feature is that the basic circle is arranged concentrically with the fuel injection hole and has a smaller diameter than the fuel injection hole.
[0010]
  According to the fourth feature, the fuel swirled in the swirl chamber can be smoothly injected from the fuel injection hole, and the high swirl speed of the fuel spray foam can be maintained, greatly promoting fuel atomization. Can contribute.
[0011]
  Furthermore, in the present invention, in addition to any of the first to fourth features, the lateral passage and the swirl chamber are formed in a slit shape in the passage plate joined between the valve seat member and the injector plate. The fifth feature.
[0012]
  According to the fifth feature, the lateral passage and the swirl chamber can be easily formed in the passage plate by pressing or laser cutting, which can contribute to cost reduction.
[0013]
  Furthermore, in addition to the first to fifth features, the present invention arranges a plurality of the lateral passages radially,Rotating direction of swirl applied to fuel in each swirl chamber is the sameEach lateral passageTheOpen to each swirl chamberLetAnd a plurality of the fuel injection holes that respectively open into the plurality of swirl chambers are formed by the fuel injected from the fuel injection holes and are adjacent to each other in a hollow conical fuel spray formLiquid film parts of each otherThe sixth feature is that they are arranged so as to cause a frontal collision.
[0014]
  According to the sixth feature, when the valve is opened, the fuel injected from the plurality of swirl chambers into the corresponding fuel injection holes forms a plurality of hollow conical fuel spray foams by the action of the injection pressure and the centrifugal force. And between adjacent fuel spray foamsThemLiquid film partMutualThe fuel can be atomized more effectively by causing the two to collide with each other. Moreover, in the end, a single fuel spray foam with a high fuel density at the center and low at the outer periphery is formed to prevent the fuel from adhering to the inner wall of the engine intake passage as much as possible, together with the intake air. Inhaled by the engine, it can greatly contribute to improvement of engine start and output performance and reduction of fuel consumption.
[0015]
  Furthermore, in addition to the features described in the first to sixth aspects, the present invention is characterized in that the lateral passage is formed such that its cross-sectional area decreases toward the swirl chamber.
[0016]
  According to the seventh feature, when the fuel passes through the lateral passage, the flow velocity of the fuel increases as it approaches the swirl chamber, so that the swirl effect given to the fuel in the swirl chamber can be further enhanced. .
[0017]
  Furthermore, in addition to the first to seventh features, the present invention has an eighth feature that the thickness of the injector plate is set smaller than the inner diameter of the fuel injection hole.
[0018]
  According to the eighth feature, the center angle of the hollow conical fuel spray foam generated from the fuel injection hole is sufficiently enlarged, the collision force between adjacent fuel spray foams is increased, and the fuel is atomized. It can be further promoted.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.
[0020]
  1 is a longitudinal sectional view of an electromagnetic fuel injection valve for an internal combustion engine according to a first embodiment of the present invention, FIG. 2 is an enlarged view of a main part of FIG. 1, and FIG. 3 is a sectional view taken along line 3-3 of FIG. 4 is a cross-sectional view taken along line 4-4 in FIG. 2, FIG. 5 is a view taken along arrow 5 in FIG. 2, FIG. 6 is an enlarged cross-sectional view taken along line 6-6 in FIG. 8 shows a second embodiment of the present invention, corresponding to FIG. 5, FIG. 9 shows a third embodiment of the present invention, corresponding to FIG. 5, and FIG. 10 shows a fourth embodiment of the present invention. FIG. 11 is a view corresponding to FIG. 2, FIG. 11 is a view taken along arrow 11 in FIG. 10, FIG. 12 is a view corresponding to FIG. 6, showing a fifth embodiment of the present invention, and FIG. ) And fuel spray foams (B) and (C) according to the present invention.
[0021]
  First, a first embodiment of the present invention shown in FIGS. 1 to 7 will be described.
[0022]
  In FIG. 1, a casing 1 of an electromagnetic fuel injection valve I for an internal combustion engine includes a cylindrical valve housing 2 (magnetic material) and a bottomed cylindrical valve that is liquid-tightly coupled to a front end portion of the valve housing 2. The seat member 3 includes a cylindrical fixed core 5 that is liquid-tightly coupled to the rear end of the valve housing 2 with an annular spacer 4 interposed therebetween.
[0023]
  The annular spacer 4 is made of a non-magnetic metal such as stainless steel, and the valve housing 2 and the fixed core 5 are abutted against both end faces of the annular spacer 4 and are welded all around the liquid.
[0024]
  A first fitting cylinder portion 3a and a second fitting cylinder portion 2a are formed at opposite ends of the valve seat member 3 and the valve housing 2, respectively. And the 1st fitting cylinder part 3a is press-fitted with the stopper plate 6 in the 2nd fitting cylinder part 2a, and the stopper plate 6 is clamped between the valve housing 2 and the valve seat member 3. FIG. Thereafter, by performing laser welding or beam welding over the entire circumference of the corner sandwiched between the outer peripheral surface of the first fitting tube portion 3a and the end surface of the second fitting tube portion 2a, the valve housing 2 and the valve seat member 3 are provided. Are liquid-tightly coupled to each other.
[0025]
  The valve seat member 3 is provided with a conical valve seat 8 having a downstream end opened on the front end surface thereof, and a cylindrical guide hole 9 connected to the upstream end of the valve seat 8, that is, the large diameter portion. The guide hole 9 is formed coaxially with the second fitting cylinder portion 2a.
[0026]
  A movable core 12 facing the front end surface of the fixed core 5 is slidably accommodated in the valve housing 2 and the annular spacer 4. The movable core 12 is accommodated in the guide hole 9 so as to be slidable in the axial direction. The valve body 16 is integrally coupled. The valve body 16 is in contact with the stopper plate 6 in contact with a spherical valve portion 16a that can be seated on the valve seat 8, a pair of front and rear journal portions 16b and 16b that are slidably supported in the guide hole 9. A flange 16c that defines the valve opening limit of the body 16 is integrally provided, and each journal portion 16b is provided with a plurality of chamfered portions 17, 17,.
[0027]
  The fixed core 5 has a hollow portion 21 communicating with the inside of the valve housing 2, and the movable core 12 is urged in the hollow portion 21 in the closing direction of the valve body 16, that is, in the seating direction on the valve seat 8. A coiled valve spring 22 and a pipe-shaped retainer 23 that supports the rear end of the valve spring 22 are accommodated.
[0028]
  An inlet cylinder 25 having a fuel inlet 25a communicating with the hollow portion 21 of the fixed core 5 through a pipe-like retainer 23 is integrally connected to the rear end of the fixed core 5, and a fuel filter 27 is connected to the fuel inlet 25a. Is installed.
[0029]
  A coil assembly 28 is fitted on the outer periphery of the annular spacer 4 and the fixed core 5. The coil assembly 28 includes a bobbin 29 fitted to the outer peripheral surface of the annular spacer 4 and the fixed core 5, and a coil 30 wound around the bobbin 29, and a coil housing 31 surrounding the coil assembly 28. Is connected to the outer peripheral surface of the valve housing 2 by welding.
[0030]
  The coil housing 31, the coil assembly 28, and the fixed core 5 are embedded in a cover 32 made of synthetic resin, and a coupler that accommodates a connection terminal 33 connected to the coil 30 in the middle of the cover 32. 34 are continuously provided.
[0031]
  As shown in FIGS. 2 to 5, the same steel plate injector plate 36 is welded to the front end face of the valve seat member 3 in a liquid-tight manner with a steel plate passage plate 35 interposed therebetween. The passage plate 35 extends in the axial direction from the peripheral edge of the downstream end of the valve seat 8, and has a large number of side holes 37, 37... Arranged at equal intervals around the axis of the valve seat 8, and these side holes 37, 37. A large number of lateral passages 38, 38 ... extending radially outward from the radial direction, and a large number of swirl chambers 39, 39 ... whose downstream ends are opened tangentially. Of plate 35Injector tap Groove on the surface facing the rate 36Provided in the shape.
[0032]
  These swirl chambers 39 are arranged at equal intervals around the axis of the valve seat 8. Each lateral passage 38CorrespondsIn each swirl chamber 39,Swirl that is given to fuel in each swirl chamber 39Are opened so that the rotation directions are the same (clockwise in FIGS. 4 and 7).
[0033]
  The injector plate 36 is provided with a plurality of fuel injection holes 40, 40, which open to the plurality of swirl chambers 39, 39, respectively. The injector plate 36 has a plate thickness smaller than the inner diameter of each fuel injection hole 40, and each fuel injection hole 40 is arranged so that its axis is parallel to the axis of the valve seat 8.
[0034]
  As clearly shown in FIG. 6, the inner peripheral surface of each swirl chamber 39 is divided into a plurality of inlet regions 39a, intermediate regions 39b, and outlet regions 39c along the fuel swirl direction, and the curvature radius R1 of these regions is divided. , R2, R3 are reduced in that order as R1> R2> R3. Therefore, the curvature of the inner peripheral surface of each swirl chamber 39 isUpstream of the swirl applied to the fuel in the direction along the inner peripheral surfaceFrom the sidedownstreamWill increase towards the side.
[0035]
  Each fuel injection hole 40 is disposed at an offset of a predetermined distance e from the center of the corresponding swirl chamber 39 to the upstream end side of the corresponding lateral passage 38. Further, as shown in FIG. 5, a large number of fuel injection holes 40, 40... Are arranged so that their adjacent interval p is 2.5 mm or less.
[0036]
  Again, in FIG. 1, an annular seal holder 48 is fitted to the outer periphery from the valve housing 2 to the valve seat member 3, and this seal holder 48 and a synthetic resin fitted to the front end portion of the valve seat member 3. An annular groove 46 is defined between the cap 45 and the O-ring 47 that is in close contact with the outer peripheral surface of the valve seat member 3. When the electromagnetic fuel injection valve I is installed in a fuel injection valve mounting hole of an intake manifold (not shown), the O-ring 47 comes into close contact with the inner peripheral surface of the mounting hole.
[0037]
  Next, the operation of the first embodiment will be described.
When the coil 30 is demagnetized, the movable core 12 and the valve body 16 are pressed forward by the urging force of the valve spring 22, and the valve portion 16 a is seated on the valve seat 8. Therefore, the high-pressure fuel supplied into the valve housing 2 through the fuel filter 27 and the inlet cylinder 26 is made to wait in the valve housing 2.
[0038]
  When the coil 30 is excited by energization, the magnetic flux generated by the coil 30 sequentially travels through the fixed core 5, the coil housing 31, the valve housing 2, and the movable core 12, and the movable core 12 is attracted to the fixed core 5 together with the valve body 16 by the magnetic force. Since the valve seat 8 is opened, the high-pressure fuel in the valve housing 2 passes through the valve seat 8 via the chamfered portions 17, 17... The holes 37 move to the corresponding swirl chambers 39 through the corresponding lateral passages 38, 38, respectively, and flow into the corresponding swirl chambers 39 at high speed, so that the fuel flows into the respective swirl chambers 39. A swirl is given by turning at a high speed.
[0039]
  In particular, since the curvature of the inner peripheral surface of each swirl chamber 39 increases from the inlet side to the outlet side of the chamber 39, the fuel that has entered the swirl chamber 39 swirls along the inner peripheral surface of the chamber 39. The turning force is strengthened as the operation proceeds.
[0040]
  Each fuel injection hole 40 is arranged at a predetermined distance e offset from the center of each swirl chamber 39 to the upstream end side of the corresponding lateral passage 38, so that most of the fuel flowing into the swirl chamber 39 is swirled. The fuel is injected from the fuel injection hole 40 during approximately one rotation of the motor 39, and the fuel speed loss in the swirl chamber 39 is small.
[0041]
  As a result, the fuel injected from each swirl chamber 39 into the corresponding fuel injection hole 40 forms a hollow conical fuel spray foam F1 by the action of a large injection pressure and centrifugal force, and maintains a high swirl speed. Therefore, the atomization of fuel can be promoted more effectively, and the responsiveness of fuel injection can be improved.
[0042]
  FIG. 13 (A) shows the formation state of the fuel spray foam F1 when tested with a single fuel injection hole 40, and FIG. 13 (B) shows the distance between the two fuel injection holes 40, 40 being 2.4 mm. FIG. 13C shows the state of formation of the fuel spray foams F1 and F2 when the test is performed with the distance between the three fuel injection holes 40, 40 and 40 set to 1.3 mm. It shows the formation state of the fuel spray foams F1 and F2 when tested.
[0043]
  As shown in FIG. 13A, the hollow conical fuel spray form F1 generated from the single fuel injection hole 40 exhibits a layered liquid film state immediately after exiting the fuel injection hole 40, and then the liquid yarn In this first embodiment, a large number of fuel injection holes 40, 40,... Are arranged around the axis of the valve seat 8 with an adjacent interval as narrow as 2.5 mm or less. Since the swirl in the same direction is given to the fuel in the swirl chamber 39, a large number of hollow conical fuel spray foams F1, F1,..., As shown in FIG. The liquid film part is adjacent to each other in the film stateMutualWill collide head-on. As a result, the liquid yarn state of all fuel spray foams F1, F1,... Is accelerated, and fuel atomization can be effectively promoted accordingly. Moreover, many fuel spray foams F1, F1 ...Liquid film parts of each otherBy causing a frontal collision, the fuel spray foam F1 having a high fuel density at the center and low at the outer periphery is finally formed, thereby preventing the fuel from adhering to the inner wall of the intake passage of the engine as much as possible. In other words, it is sucked into the engine together with the intake air, which can greatly contribute to improvement of engine startability and output performance and reduction of fuel consumption.
[0044]
  According to the test, the end of the liquid film state of a large number of fuel spray foams F1, F1,... Is in a region 0.5 to 3.0 mm away from the injector plate 36, and in this region, a large number of fuel spray foams F1, F1. It was confirmed that the atomization of the fuel could be effectively promoted by colliding .... In order to obtain such a collision between the fuel spray foams F1, F1,..., It is extremely effective to set the adjacent intervals of the many fuel injection holes 40, 40. .
[0045]
  Further, by setting the thickness of the injector plate 36 to be smaller than the inner diameter of each fuel injection hole 40, the center angle of each of the hollow conical fuel spray foams F1 is sufficiently expanded, and the adjacent fuel spray foams F1, F1,. It is possible to increase the collision force between the liquid film portions of each other and further promote atomization of the fuel.
[0046]
  Further, by arranging the axes of the many fuel injection holes 40, 40 ... in parallel, the fuel injection holes 40, 40 ... can be coaxially processed with high accuracy. As a result, the fuel spray foams F1, F1,... Generated from all the fuel injection holes 40, 40... Are always uniform, and a stable collective fuel spray foam F2 is always formed by a frontal collision between the liquid film portions. This can further contribute to improvement of engine startability and output performance and reduction of fuel consumption.
[0047]
  Next, a second embodiment of the present invention shown in FIG. 8 will be described.
[0048]
  In this second embodiment, a large number of side holes 37, 37... Are arranged in a staggered manner on a plurality of concentric circles, and a large number of the swirl chambers 39, 39. Except for this, the configuration is the same as that of the previous embodiment. In FIG. 8, the same reference numerals are assigned to the portions corresponding to those of the previous embodiment, and the description thereof is omitted.
[0049]
  According to the second embodiment, it is possible to form one relatively large collective fuel spray foam F2 from more fuel spray foams F1, F1,..., Which is suitable for a large engine.
[0050]
  Next, a third embodiment of the present invention shown in FIG. 9 will be described.
[0051]
  The third embodiment has the same configuration as that of the first embodiment except that a plurality of swirl chambers 39, 39,... Are arranged inside the plurality of side holes 37, 37,. In FIG. 9, parts corresponding to those of the first embodiment are designated by the same reference numerals, and the description thereof is omitted.
[0052]
  According to the third embodiment, one relatively small collective fuel spray foam F2 can be formed from a plurality of fuel spray foams F1, F1,..., Which is suitable for a small engine.
[0053]
  Next, a fourth embodiment of the present invention shown in FIGS. 10 and 11 will be described.
[0054]
  In the fourth embodiment, a circular distribution chamber 50 connected to the downstream edge of the valve seat 8 is formed in the passage plate 35, and a large number of swirl chambers 39, 39. Points where the lateral passages 38, 38.And the lateral passages 38, 38... And the swirl chambers 39, 39... Are provided in a slit shape so as to penetrate the front and back of the passage plate 35.Except for the above, the configuration is the same as that of the first embodiment. In FIGS. 10 and 11, the same reference numerals are assigned to the portions corresponding to those of the first embodiment, and the description thereof is omitted.
[0055]
  According to the fourth embodiment, since the fuel is distributed from the common distribution chamber 50 to the multiple lateral passages 38, 38,..., The multiple side holes 37, 37, etc. as in the first embodiment are unnecessary. This can contribute to the simplification of the structure, but the volume of the common distribution chamber 50 is larger than the total volume of the side holes 37, 37... In the first embodiment. It is disadvantageous than the embodiment.
[0056]
  Finally, a fifth embodiment of the present invention shown in FIG. 12 will be described.
[0057]
  In this fifth embodiment, the cross-sectional area of the lateral passage 38 extending from each side hole 37 to each corresponding swirl chamber 39 is gradually reduced toward the downstream side, that is, the swirl chamber 39. The inner circumferential surface of each swirl chamber 39 is formed along an involute curve 52 having a base circle 51 that is smaller in diameter than the fuel injection hole 40 and is concentrically arranged therewith. The other configuration is the same as that of the first embodiment. In FIG. 12, the same reference numerals are assigned to portions corresponding to the first embodiment, and the description thereof is omitted.
[0058]
  According to the fifth embodiment, since the flow velocity of the fuel that has flowed out from the side holes 37 to the lateral passage 38 increases as it approaches each corresponding swirl chamber 39, the swirl effect that is given to the fuel in the swirl chamber 39. Can be increased. At the same time, as the fuel that has entered the swirl chamber 39 from the lateral passage 38 advances turning along the inner peripheral surface of the chamber 39, the turning force can be continuously and smoothly enhanced. Giving the spray foam a high swirl speed can greatly contribute to the promotion of fuel atomization.
[0059]
  The present invention is not limited to the above embodiments, and various design changes can be made without departing from the scope of the invention.
[0060]
【The invention's effect】
  As described above, according to the first feature of the present invention,valveA lateral direction communicating with the downstream end of the valve seat between a valve seat member whose downstream end of the valve seat cooperating with the body opens on the front end surface and an injector plate joined to the front end surface of the valve seat member A fuel injection valve having a passage and a swirl chamber in which the downstream end of the lateral passage opens in a tangential direction, and a fuel injection hole for injecting the swirled fuel in the swirl chamber is formed in the injector plate The fuel injection hole is disposed with a predetermined distance offset from the center of the swirl chamber to the upstream end side of the lateral passage, so that most of the fuel that has flowed into the swirl chamber from the lateral passage is substantially in the swirl chamber. It will be injected from the fuel injection hole during one rotation, and the fuel spray foam formed by the injected fuel maintains a high swirl speed, which can effectively promote fuel atomization. , Yet it is possible to improve the responsiveness of the fuel injection, improving startability and output performance of the engine, as well as contribute to a reduction in fuel consumption.
[0061]
  According to the second feature of the present invention, the curvature of the inner peripheral surface of the swirl chamberUpstream of the swirl applied to the fuel in the direction along the inner peripheral surfaceFrom the sidedownstreamAs the fuel that has entered the swirl chamber from the lateral passage advances turning along the inner peripheral surface of the chamber, the turning force is strengthened and generated from the fuel injection hole. By increasing the swirl speed of the fuel spray foam, atomization of the fuel can be promoted more effectively.
[0062]
  Further, according to the third feature of the present invention, since the inner peripheral surface of the swirl chamber is formed along an involute curve having a base circle in the chamber, the fuel that has entered the swirl chamber from the lateral passage is in the chamber. As the turning progresses along the inner peripheral surface of the fuel, the turning force can be continuously and smoothly strengthened, giving the fuel spray foam a high swirl speed and greatly contributing to the promotion of fuel atomization. obtain.
[0063]
  Furthermore, according to the fourth feature of the present invention, the base circle is concentrically arranged with the fuel injection hole and has a smaller diameter than the fuel injection hole, so that the fuel provided with the swirl in the swirl chamber is fueled. Smooth injection from the nozzle hole can maintain the high swirl speed of the fuel spray foam, which can greatly contribute to the promotion of fuel atomization.
[0064]
  Furthermore, according to the fifth aspect of the present invention, the lateral passage and the swirl chamber are formed in a slit shape in the passage plate joined between the valve seat member and the injector plate. The lateral passage and the swirl chamber can be easily formed in the passage plate, which can contribute to cost reduction.
[0065]
  Furthermore, according to the sixth aspect of the present invention, a plurality of the transverse passages are arranged radially,Rotating direction of swirl applied to fuel in each swirl chamber is the sameEach lateral passageTheOpen to each swirl chamberLetAnd a plurality of the fuel injection holes that respectively open into the plurality of swirl chambers are formed by the fuel injected from the fuel injection holes and are adjacent to each other in a hollow conical fuel spray formLiquid film parts of each otherSince it is arranged so that it collides front, the fuel injected from the plurality of swirl chambers to the corresponding fuel injection holes at the time of valve opening forms a plurality of hollow conical fuel spray foams by the action of injection pressure and centrifugal force. And between adjacent fuel spray foamsThemLiquid film partMutualThe fuel can be atomized more effectively by causing the two to collide with each other. Moreover, in the end, a single fuel spray foam with a high fuel density at the center and low at the outer periphery is formed to prevent the fuel from adhering to the inner wall of the engine intake passage as much as possible, together with the intake air. Inhaled by the engine, it can greatly contribute to improvement of engine start and output performance and reduction of fuel consumption.
[0066]
  Furthermore, according to the seventh aspect of the present invention, the cross-sectional area of the lateral passage is formed so as to decrease toward the swirl chamber, so that when the fuel passes through the lateral passage, Since the flow velocity increases as it approaches the swirl chamber, the swirl effect on the fuel in the swirl chamber can be further enhanced.
[0067]
  Furthermore, according to the eighth feature of the present invention, since the plate thickness of the injector plate is set smaller than the inner diameter of the fuel injection hole, the center angle of the hollow conical fuel spray foam generated from the fuel injection hole is sufficiently set. To increase the collision force between adjacent fuel spray foams, and further promote atomization of the fuel.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an electromagnetic fuel injection valve for an internal combustion engine according to a first embodiment of the present invention.
FIG. 2 is an enlarged view of the main part of FIG.
3 is a cross-sectional view taken along line 3-3 in FIG.
4 is a cross-sectional view taken along line 4-4 of FIG.
FIG. 5 is a view taken along arrow 5 in FIG.
6 is an enlarged sectional view taken along line 6-6 of FIG.
FIG. 7 is an operation explanatory diagram corresponding to FIG.
FIG. 8 is a diagram corresponding to FIG. 5, showing a second embodiment of the present invention.
FIG. 9 is a diagram corresponding to FIG. 5, showing a third embodiment of the present invention.
FIG. 10 is a diagram corresponding to FIG. 2, showing a fourth embodiment of the present invention.
11 is a view taken in the direction of arrow 11 in FIG.
FIG. 12 is a diagram corresponding to FIG. 6, showing a fifth embodiment of the present invention.
FIG. 13 is a diagram illustrating comparison between a conventional fuel spray foam (A) and fuel spray foams (B) and (C) according to the present invention.
[Explanation of symbols]
I: Fuel injection valve
3. Valve seat member
8 ... Valve seat
35 .. Passage plate
36 .... Injector plate
38 .... Transverse passage
39 ... Swirl room
40... Fuel injection hole
51 ... Basic circle
52 ... Involute curve

Claims (8)

Injector plate downstream end which is joined to the valve seat member to open the front end surface (3), the front end face of the valve seat member (3) of the valve body (16) cooperating with the valve seat (8) (36) Are formed with a lateral passage (38) communicating with the downstream end of the valve seat (8) and a swirl chamber (39) with the downstream end of the lateral passage (38) opening in a tangential direction. In the fuel injection valve in which the fuel injection hole (40) for injecting the fuel provided with the swirl in the swirl chamber (39) is formed in the injector plate (36),
The fuel injection valve, wherein the fuel injection hole (40) is arranged at a predetermined distance (e) offset from the center of the swirl chamber (39) to the upstream end side of the lateral passage (38). The fuel injection valve according to claim 1, wherein
The curvature of the inner peripheral surface of the swirl chamber (39) is increased from the upstream side to the downstream side in the direction along the inner peripheral surface of the swirl applied to the fuel in the chamber (39). Fuel injection valve. The fuel injection valve according to claim 2, wherein
The fuel injection valve characterized in that the inner peripheral surface of the swirl chamber (39) is formed along an involute curve (52) having a base circle (51) in the chamber (39). The fuel injection valve according to claim 3, wherein
The fuel injection valve characterized in that the basic circle (51) is arranged concentrically with the fuel injection hole (40) and has a smaller diameter than the fuel injection hole (40). The fuel injection valve according to any one of claims 1 to 4,
The fuel injection characterized in that the lateral passage (38) and the swirl chamber (39) are formed in a slit shape in the passage plate (35) joined between the valve seat member (3) and the injector plate (36). valve. In the fuel injection valve in any one of Claims 1-5,
Said lateral passage (38) while disposed in a plurality radially, each swirl chamber (39) in each transverse channel so that the rotation direction of the swirl imparted to the fuel are the same (38) each swirl chamber ( 39). to the opening, a plurality of the swirl chamber more the fuel injection holes (40) which opens respectively (39), a hollow conical adjacent formed by fuel injected from these fuel injection holes (40) A fuel injection valve, characterized in that the liquid film portions of the fuel spray foam (F1) are arranged to collide with each other in front of each other . The fuel injection valve according to claim 1,
The fuel injection valve according to claim 1, wherein the transverse passage (38) is formed so that a cross-sectional area thereof decreases toward the swirl chamber (39). The fuel injection valve according to claim 1,
The fuel injection valve according to claim 1, wherein a thickness of the injector plate (36) is set smaller than an inner diameter of the fuel injection hole (40).

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