JP3784748B2 - Fuel injection valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a fuel injection valve mainly used for a fuel supply system of an internal combustion engine, and in particular, a valve body, a valve seat member whose downstream end of a valve seat cooperating with the valve body is opened at a front end surface, An injector plate joined to the front end surface of the valve seat member, and communicates with the downstream end of the valve seat between the valve seat member and the injector plate and is substantially orthogonal to the axis of the valve seat And a plurality of swirl chambers whose downstream ends are opened in a tangential direction, respectively, and a plurality of fuel swirled in the swirl chamber is injected to the outside. The present invention relates to an improvement in a fuel injection valve in which a fuel injection hole is formed in the injector plate.
[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 is intended to promote atomization of the injected fuel by applying swirl to the fuel injected from the fuel injection hole. A plurality of lateral passages are radially extended from one central opening that communicates, and when the valve is opened, the fuel that has passed through the valve seat is once collected in the central opening and then distributed to the plurality of lateral passages. Therefore, the central opening must have a sufficient volume for smooth fuel collection and distribution. However, the volume of such a central opening becomes a dead space volume when the valve is closed, and fuel remaining therein may flow out of the fuel injection hole due to a temperature rise, vibration, or the like, thereby deviating the fuel injection amount. Further, turbulent flow occurs in the distributed fuel due to the collection and distribution of the fuel at the central opening, so that it is difficult to evenly distribute the fuel to the plurality of swirl chambers. Therefore, the fuel foam generated from each fuel nozzle is made uniform. Is difficult.
[0004]
  The present invention has been made in view of such circumstances, and when the valve is closed, the space occupied by the residual fuel from the valve seat to the fuel injection hole is made as small as possible to improve the accuracy of the fuel injection amount. An object of the present invention is to provide the fuel injection valve capable of promoting atomization of the injected fuel.
[0005]
[Means for Solving the Problems]
  To achieve the above objective,Claim 1The present invention includes a valve body, a valve seat member having a downstream end of a valve seat that cooperates with the valve body, and an injector plate that is joined to the front end surface of the valve seat member. A plurality of lateral passages that communicate with the downstream end of the valve seat between the member and the injector plate and extend in a lateral direction substantially orthogonal to the axis of the valve seat, and the downstream ends of the lateral passages are tangent to each other A fuel injection valve having a plurality of fuel injection holes formed in the injector plate, each of which has a plurality of fuel injection holes for injecting fuel swirled in the swirl chambers to the outside. An intermediate plate is joined between the member and the injector plate, and the lateral passage and the swirl chamber are formed in a groove shape on the surface of the intermediate plate facing the injector plate. In the rate, the entire end of each end is opened inside the peripheral edge of the downstream end of the valve seat and extends linearly so as to penetrate the front and back of the intermediate plate, and the other end is connected to the upstream end of the corresponding lateral passage. Provide multiple side holes to connectThe plurality of side holes are staggered on two pitch circles concentric with the valve seat, and the plurality of swirl chambers are concentric with the two pitch circles and on two pitch circles having a larger diameter than them. Arranged in a staggered patternThatSpecialIt is a sign.
[0006]
  According to a second aspect of the present invention, in addition to the above-described configuration of the first aspect, the side holes are displaced radially outwardly toward the lateral passages corresponding to the side holes. Inclined It is characterized by that.
[0007]
  According to a third aspect of the present invention, there is provided a valve body, a valve seat member having a downstream end of a valve seat that cooperates with the valve body, and an injector plate joined to the front end face of the valve seat member. A plurality of lateral passages that communicate with the downstream end of the valve seat between the valve seat member and the injector plate and extend in a lateral direction substantially orthogonal to the axis of the valve seat; and A fuel injection valve having a plurality of swirl chambers whose downstream ends each open in a tangential direction, and a plurality of fuel injection holes for injecting fuel swirled in the swirl chamber to the outside. An intermediate plate is joined between the valve seat member and the injector plate, and the lateral passage and the swirl chamber are formed in a groove shape on a surface of the intermediate plate facing the injector plate. Further, the intermediate plate has an opening at the inner peripheral edge of the downstream end of the valve seat and extends linearly so as to penetrate the front and back of the intermediate plate, and the other end of the corresponding transverse passage. A plurality of side holes connected to the upstream end are provided, and each swirl chamber is disposed radially inward of the valve seat from the side hole corresponding to each swirl chamber.
[0008]
  According to a fourth aspect of the present invention, in addition to the structure of any one of the first to third aspects, each of the lateral passages is set to a radial line of the valve seat passing through the center of the side hole corresponding to each of the lateral passages. The angle positions of the corresponding side holes and swirl chambers with respect to the center of the valve seat are shifted with respect to each other.
[0009]
  According to a fifth aspect of the present invention, in addition to the structure of any one of the first to fourth aspects, each of the lateral passages moves outwardly in the axial direction of the valve seat toward the swirl chamber corresponding to each lateral passage. It is characterized by being inclined so as to be displaced.
[0010]
  The above of the invention of each claimAccording to the feature, when the valve is opened, the fuel that has passed through the valve seat is immediately and equally divided into a plurality of lateral passages through a plurality of side holes that are connected to the peripheral edge of the downstream end of the valve seat, and is supplied to each corresponding swirl chamber. Swirl is applied by flowing in the tangential direction at high speed. The fuel injected from each corresponding fuel injection hole forms a uniform hollow conical fuel spray foam by the action of injection pressure and centrifugal force, and can promote atomization of the fuel. In addition, the entire upstream end of each side hole that is individually connected to each lateral passage is opened inside the periphery of the valve seat, so that when the valve is closed, the dead space volume occupied by the residual fuel from the valve seat to each fuel injection hole is reduced. It is possible to reduce the fuel injection amount, and it is possible to improve the accuracy of the fuel injection amount due to the uniform fuel distribution to each swirl chamber.. ShiIn addition, an intermediate plate is joined between the valve seat member and the injector plate, and a lateral passage and a swirl chamber are formed in a groove shape on the surface of the intermediate plate facing the injector plate, and the intermediate plate penetrates the front and back surfaces thereof. By forming the side holes extending in a straight line, the plurality of side holes, the lateral passages and the swirl chamber can be easily machined with high precision into the intermediate plate of the small parts, and the groove-shaped lateral holes are formed. By setting the groove width and depth of the directional passage and the swirl chamber, it is possible to form a lateral passage and a swirl chamber having different specifications on an intermediate plate having the same plate thickness, thereby obtaining versatility.
[0011]
  Further, in particular, according to the feature of the invention of claim 1, the plurality of side holes are arranged in a staggered manner on two pitch circles concentric with the valve seat, and the plurality of swirl chambers are concentric with the two pitch circles. Since they are arranged in a zigzag pattern on two large-diameter pitch circles, it is possible to provide more swirl chambers and fuel injection holes around the plurality of side holes, which is suitable for a large fuel flow specification.
[0012]
  In particular, the invention of claim 2According to the characteristics, when the fuel moves from each side hole to the lateral passage, the fuel flow is not sharply bent, and the flow is smooth, so that the fuel speed loss is small, and therefore in the swirl chamber. The swirl effect on the fuel can be enhanced.
[0013]
  In particular, the invention of claim 3According to this feature, the pitch circle of the plurality of fuel injection holes can be made sufficiently small, which is suitable for the specification of a small flow rate of fuel.
[0014]
  In particular, the invention of claim 4According to the feature, even when the difference in diameter between the pitch circles of the plurality of side holes and the pitch circles of the plurality of swirl chambers is small, each lateral passage can be set to be long and tangential to each swirl chamber. In order to prevent the adhesion of fuel to the inner wall of the engine intake port, it is possible to accurately induce laminar flow of the fuel, obtain a good swirl effect of the fuel in each swirl chamber, and make the fuel spray foam compact. Can contribute.
[0015]
  In particular, the invention of claim 5According to the characteristics, when the fuel flows from each side hole to the lateral passage and the swirl chamber, the flow of the fuel is not sharply bent and the flow becomes smooth, so that the speed loss of the fuel is small. Therefore, the swirl effect on the fuel in the swirl chamber can be enhanced..
[0016]
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.
[0017]
  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. 5 is a diagram corresponding to FIG. 5, FIG. 11 is a diagram obtained by a test showing the relationship between the magnification of the side hole total opening area A with respect to the fuel nozzle total opening area B and the maximum fuel injection amount, and FIG. When the number of holes is one (A), when the number of fuel nozzle holes is two (B), and when the number of adjacent fuel nozzle holes is narrower than that of (B) is three (C) It is comparison explanatory drawing of spray foam.
[0018]
  First, a first embodiment of the present invention shown in FIGS. 1 to 7 will be described.
[0019]
  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.
[0020]
  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.
[0021]
  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.
[0022]
  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.
[0023]
  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,.
[0024]
  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.
[0025]
  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.
[0026]
  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.
[0027]
  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.
[0028]
  As shown in FIGS. 2 to 5, the same steel plate injector plate 36 is liquid-tightly welded to the front end surface of the valve seat member 3 with a steel plate intermediate plate 35 interposed therebetween.
[0029]
  In the intermediate plate 35, a large number of side holes 37 extending in a substantially axial direction from the peripheral edge of the downstream end of the valve seat 8 so as to penetrate the front and back of the intermediate plate 35 and arranged at equal intervals around the axis of the valve seat 8. 37, and a plurality of lateral passages radially extending from the side holes 37, 37 ... radially outward of the valve seat 8 on the surface of the intermediate plate 35 facing the injector plate 36. And a plurality of swirl chambers 39, 39, whose downstream ends of the lateral passages 38, 38 are opened in a tangential direction are formed in a groove shape.
[0030]
  In this case, preferably, each side hole 37 is inclined so as to be displaced radially outwardly of the valve seat 8 toward the corresponding lateral passage 38, and each lateral passage 38 is arranged on the side passage 37. It is arranged so as to be inclined so as to be displaced outward in the axial direction toward the corresponding swirl chamber 39.
[0031]
  The plurality of swirl chambers 39, 39,... Are also arranged at equal intervals around the axis of the valve seat 8, like the side holes 37, 37,. The tangential direction of each lateral passage 38 opening to each swirl chamber 39 is constant, and the swirl direction applied to the fuel in each swirl chamber 39 is constant.
[0032]
  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.
[0033]
  As clearly shown in FIG. 6, each fuel injection hole 40 is arranged with a predetermined distance e offset 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.
[0034]
  Here, when the total opening area of the large number of side holes 37, 37... Is A and the total opening area of the large number of fuel injection holes 40, 40. The side holes 37, 37... And the fuel injection holes 40, 40.
[0035]
  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.
[0036]
  Next, the operation of the first embodiment will be described.
In a state where 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. Accordingly, the high-pressure fuel supplied into the valve housing 2 through the fuel filter 27 and the inlet cylinder 25 is made to wait in the valve housing 2.
[0037]
  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 fuel is diverted into the side holes 37, 37, and flows into the corresponding swirl chambers 39 at high speed from the side holes 37, 37 through the corresponding lateral passages 38, 38, respectively. A swirl is applied by turning the chamber 39 at high speed.
[0038]
  In particular, each side hole 37 is inclined so as to displace radially outward of the valve seat 8 toward the corresponding lateral passage 38, and the axis of each lateral passage 38 as it moves toward the corresponding swirl chamber 39. In the case of being arranged so as to be displaced outward in the direction, the fuel flow is not sharply bent until it reaches the swirl chamber 39 through each side hole 37 and the lateral passage 38, and the flow is reduced. Because it becomes smooth, there is little fuel speed loss.
[0039]
  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.
[0040]
  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.
[0041]
  In addition, since the entire upstream ends of the large number of side holes 37, 37 ... individually connected to the large number of lateral passages 38, 38 ... are respectively opened to the inside of the peripheral edge of the valve seat 8, The dead space volume occupied by the residual fuel up to the fuel injection hole 40 can be reduced, which can contribute to improving the accuracy of the fuel injection amount. In particular, if each side hole 37 and each fuel injection hole 40 are formed so as to satisfy A / B = 1.5 to 3.0 as described above, as is clear from the test data of FIG. With a limited dead space volume, the fuel injection amount from each fuel injection hole 40 at the time of full load can be secured stably without being affected by the throttle resistance of each side hole 37.
[0042]
  FIG. 12A shows the formation state of the fuel spray foam F1 when tested with a single fuel injection hole 40. FIG. 12B shows the distance between the two fuel injection holes 40, 40 of 2.4 mm. FIG. 12C shows the state of formation of the fuel spray foams F1 and F2 when the test is performed while setting the distance between the three fuel injection holes 40, 40 and 40 to 1.3 mm. It shows the formation state of the fuel spray foams F1 and F2 when tested.
[0043]
  As shown in FIG. 12A, the hollow conical fuel spray foam 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. In the film state, the liquid film portions are collided with each other adjacent to each other. As a result, the liquid yarn state of all fuel spray foams F1, F1,... Is accelerated, and fuel atomization can be effectively promoted accordingly. In addition, a large number of fuel spray foams F1, F1,... Collide each other with the liquid film portion in the front, so that finally a fuel spray foam F1 having a high fuel density at the center and low at the outer periphery is formed. Therefore, while preventing the fuel from adhering to the inner wall of the intake passage of the engine as much as possible, it is sucked into the engine together with the intake air, which can greatly contribute to the improvement of the startability and output performance of the engine and the 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 hollow conical fuel spray foam F1 can be sufficiently expanded, and a large number of fuel spray foams F1, F1,. Can be reliably collided with each other in a liquid film state, and atomization of fuel can be further promoted.
[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]
  In the first embodiment, a large number of lateral passages 38, 38... And swirl chambers 39, 39... Are formed in a groove shape on the surface of the intermediate plate 35 facing the injector plate 36, and a large number of side holes. 37, 37... Are formed in the intermediate plate 35 so as to penetrate the front and back surfaces thereof, so that a plurality of side holes 37, 37..., Lateral passages 38, 38. 35 can be easily machined with high accuracy, and the groove-like lateral passages 38, 38... And the swirl chambers 39, 39. ..) And lateral swirl passages 38, 38... And swirl chambers 39, 39... Having different specifications can be formed, and versatility can be obtained.
[0048]
  The swirl chambers 39, 39... Are arranged in a ring shape on a pitch circle that is concentric with and larger than the pitch circle of the side holes 37, 37. It is possible to provide a relatively large number of swirl chambers 39, 39 ... and fuel injection holes 40, 40 ... around the group, which is suitable for a large flow rate specification of fuel.
[0049]
  Next, a second embodiment of the present invention shown in FIG. 8 will be described.
[0050]
  In this second embodiment, a large number of side holes 37, 37,... Are arranged in a zigzag pattern on two concentric pitch circles C1, C2, and accordingly, a large number of swirl chambers 39, 39,. Except for the staggered arrangement on the two pitch circles C3 and C4 that are larger in diameter than C2 and concentric with them, the configuration is the same as in the previous embodiment, and in FIG. 8, the portion corresponding to the previous embodiment Are denoted by the same reference numerals, and the description thereof is omitted.
[0051]
  According to the second embodiment, it is possible to provide more side holes 37, 37..., Swirl chambers 39, 39... And fuel injection holes 40, 40. . Next, a third embodiment of the present invention shown in FIG. 9 will be described.
[0052]
  In this third embodiment, the plurality of swirl chambers 39, 39... Are arranged in a ring shape on a pitch circle that is concentric with and smaller than the pitch circle of the side holes 37, 37. Further, each lateral passage 38 is inclined at an angle α with respect to a radial line L1 of the valve seat 8 passing through the center of the corresponding side hole 37, and each of the corresponding side holes 37 and the valve seat 8 of the swirl chamber 39. The angular positions with respect to the center are shifted from each other. Since the other configuration is the same as that of the first embodiment, the same reference numerals are given to the portions corresponding to those of the first embodiment in FIG.
[0053]
  According to the third embodiment, the swirl chambers 39, 39... And the fuel injection holes 40, 40... Cannot be provided so much, but the pitch circle of the fuel injection holes 40, 40. Therefore, it is suitable for the specification of a small flow rate of fuel. In addition, even when the difference in diameter between the pitch circles of the side holes 37, 37... And the swirl chambers 39, 39... Is small, the lateral passages 38 can be set longer. It is possible to accurately induce the laminar flow of the fuel in the tangential direction and obtain a good swirl effect of the fuel in each swirl chamber 39. Further, the fuel spray foams F1 and F2 can be made compact, which can contribute to prevention of fuel adhesion to the inner wall of the engine intake port.
[0054]
  Next, a fourth embodiment of the present invention shown in FIG. 10 will be described.
[0055]
  In this fourth embodiment, each lateral passage 38 is inclined at an angle β with respect to the radial line L2 of the valve seat 8 passing through the center of the corresponding side hole 37, so that each corresponding side hole 37 and swirl chamber 39 are provided. Except that the angular positions of the valve seat 8 are shifted with respect to the center of the valve seat 8, the configuration is the same as that of the first embodiment. In FIG. 10, parts corresponding to those of the first embodiment are denoted by the same reference numerals. Therefore, the description is omitted.
[0056]
  According to the fourth embodiment, even when the diameter difference between the pitch circles of the side holes 37, 37... And the pitch circles of the swirl chambers 39, 39. It is possible to accurately guide the fuel in the tangential direction of each swirl chamber 39 and obtain a good swirl effect of the fuel in each swirl chamber 39.
[0057]
  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.
[0058]
【The invention's effect】
  As aboveEach invention of Claims 1-5In the fuel injection valve, between the valve seat and the plurality of lateral passages, the entire one end is opened inside the peripheral edge of the downstream end of the valve seat, and the other end is connected to the lateral passage. Since a plurality of side holes connected to the upstream end are provided, when the valve is opened, the fuel that has passed through the valve seat is immediately and equally divided into a plurality of lateral passages via the plurality of side holes, and each corresponding swirl chamber The fuel injected from each corresponding fuel injection hole forms a uniform hollow conical fuel spray foam by the action of the injection pressure and centrifugal force. Can be atomized. In addition, the entire upstream end of each side hole that is individually connected to each lateral passage is opened inside the periphery of the valve seat, so that when the valve is closed, the dead space volume occupied by the residual fuel from the valve seat to each fuel injection hole is reduced. It is possible to reduce the fuel injection amount, and it is possible to improve the accuracy of the fuel injection amount due to the uniform fuel distribution to each swirl chamber. Moreover, an intermediate plate is joined between the valve seat member and the injector plate, and a lateral passage and a swirl chamber are formed in a groove shape on the surface of the intermediate plate facing the injector plate, and the intermediate plate passes through the front and back sides. Since the side holes extending in a straight line are formed, a plurality of side holes, lateral passages and swirl chambers can be easily machined with high precision into an intermediate plate of small parts, and a groove-like lateral direction By setting the groove width and depth of the passage and the swirl chamber, it is possible to form lateral passages and swirl chambers having different specifications on an intermediate plate having the same thickness, and thus versatility can be obtained.
[0059]
  In particular, according to the invention of claim 1, the plurality of side holes are arranged in a staggered manner on two pitch circles concentric with the valve seat, and the plurality of swirl chambers are also concentric with the two pitch circles. Because it is arranged in a zigzag pattern on two pitch circles with a larger diameter than those, it is possible to provide more side holes, swirl chambers, and fuel injection holes around a plurality of side holes, making it suitable for fuel large flow rate specifications. It is.
[0060]
  In particular, according to the invention of claim 2, each side hole is inclined so as to be displaced outward in the radial direction of the valve seat toward the corresponding lateral passage. When moving to the lateral passage, the fuel flow is not sharply bent and the flow becomes smooth, so that there is little fuel speed loss, and therefore the swirl effect on the fuel in the swirl chamber can be enhanced.
[0061]
  In particular, the invention of claim 3Since each swirl chamber is arranged radially inward of the valve seat from the corresponding side hole, the pitch circle of the plurality of fuel injection holes can be made sufficiently small, and a small flow rate of fuel Suitable for specification.
[0062]
  In particular, the invention of claim 4In accordance with the present invention, each lateral passage is inclined with respect to a radial line of the valve seat passing through the center of the corresponding side hole, and the angular position of each corresponding side hole and swirl chamber with respect to the valve seat center is set. Since they are shifted from each other, each lateral passage can be set long even when the difference in diameter between the pitch circles of the plurality of side holes and the pitch circles of the plurality of swirl chambers is small. Accurately induces laminar flow of fuel, achieves good swirl effect of fuel in each swirl chamber, and enables compact fuel spray foam, contributing to prevention of fuel adhesion to the engine intake port inner wall Can do.
[0063]
  In particular, the invention of claim 5Since each of the lateral passages is inclined so as to be displaced outward in the axial direction of the valve seat as it goes to the corresponding swirl chamber, fuel flows from each side hole to the lateral passage and the swirl chamber. The fuel flow is smooth and the flow is smooth, so there is little fuel speed loss, and therefore the swirl effect on the fuel in the swirl chamber can be enhanced..
[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. 5, showing a fourth embodiment of the present invention.
FIG. 11 is a diagram obtained by a test showing the relationship between the magnification of the side hole total opening area A with respect to the fuel nozzle total opening area B and the maximum fuel injection amount;
FIG. 12 shows that when the number of fuel injection holes is one (A), when the number of fuel injection holes is two (B), and when the number of fuel injection holes is smaller than that of (B), the number is three. (C) Comparison diagram of fuel spray foam
[Explanation of symbols]
C1, C2 ... Two pitch circles in a side hole group in a staggered arrangement
C3, C4 ... Two pitch circles of swirl chambers arranged in a staggered pattern
I: Fuel injection valve
L1, L2 ... Radial lines of the valve seat
3. Valve seat member
8 ... Valve seat
35 ... Intermediate plate
36 .... Injector plate
37 .. Side holes
38 .... Transverse passage
39 ... Swirl room
40... Fuel injection hole

Claims (5)

A valve body (16), a valve seat member (3) whose downstream end of the valve seat (8) cooperating with the valve body (16) opens to the front end surface, and a front end surface of the valve seat member (3) An injector plate (36) to be joined, and communicated with the downstream end of the valve seat (8) between the valve seat member (3) and the injector plate (36), and the valve seat (8) Forming a plurality of lateral passages (38) extending in a lateral direction substantially orthogonal to the axis of each of the two, and a plurality of swirl chambers (39) each having a downstream end thereof opening in a tangential direction. A fuel injection valve in which a plurality of fuel injection holes (40) for injecting fuel swirled in the swirl chamber (39) to the outside are formed in the injector plate (36).
An intermediate plate (35) is joined between the valve seat member (3) and the injector plate (36), and the lateral passage (38) is formed on a surface of the intermediate plate (35) facing the injector plate (36). ) And the swirl chamber (39) are formed in a groove shape,
Further, the intermediate plate (35) is opened at the inner periphery of the downstream end of the valve seat (8) at one end and extends linearly so as to penetrate the front and back of the intermediate plate (35). Providing a plurality of side holes (37) connecting the ends to the upstream ends of the corresponding transverse passages (38) ;
The plurality of side holes (37) are arranged in a staggered manner on two pitch circles (C1, C2) concentric with the valve seat (8), and the plurality of swirl chambers (39) are arranged on the two pitch circles. A fuel injection valve characterized by being arranged in a staggered manner on two pitch circles (C3, C4) that are concentric with (C1, C2) and larger in diameter . The fuel injection valve according to claim 1, wherein
That each side hole (37), is inclined so as to be displaced radially outwardly of the valve seat (8) toward the transverse channel corresponding to each side hole of that (37) (38) A fuel injection valve that is characterized. A valve body (16), a valve seat member (3) whose downstream end of the valve seat (8) cooperating with the valve body (16) opens to the front end surface, and a front end surface of the valve seat member (3) An injector plate (36) to be joined, and communicated with the downstream end of the valve seat (8) between the valve seat member (3) and the injector plate (36), and the valve seat (8) Forming a plurality of lateral passages (38) extending in a lateral direction substantially orthogonal to the axis of each of the two, and a plurality of swirl chambers (39) each having a downstream end thereof opening in a tangential direction. A fuel injection valve in which a plurality of fuel injection holes (40) for injecting fuel swirled in the swirl chamber (39) to the outside are formed in the injector plate (36).
An intermediate plate (35) is joined between the valve seat member (3) and the injector plate (36), and the lateral passage (38) is formed on a surface of the intermediate plate (35) facing the injector plate (36). ) And the swirl chamber (39) are formed in a groove shape,
Further, the intermediate plate (35) is opened at the inner periphery of the downstream end of the valve seat (8) at one end and extends linearly so as to penetrate the front and back of the intermediate plate (35). Providing a plurality of side holes (37) connecting the ends to the upstream ends of the corresponding transverse passages (38);
Wherein each swirl chamber (39) is a fuel injection valve, characterized in that it is located radially inward of the valve seat (8) from the side holes corresponding to the respective swirl chambers of that (39) (37). The fuel injection valve according to any one of claims 1 to 3 ,
Wherein each transverse channel (38), is inclined relative to the valve seat through the center of the side hole (37) corresponding to each transverse channel of its (38) radial lines (8) (L1, L2) The fuel injection valve is characterized in that the angular positions of the corresponding side holes (37) and swirl chamber (39) with respect to the center of the valve seat (8) are shifted from each other. The fuel injection valve according to any one of claims 1 to 4 ,
Said each transverse channel (38), is inclined so as to be displaced axially outward of the valve seat (8) towards the swirl chamber corresponding to each transverse channel of that (38) (39) A fuel injection valve characterized by .

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