FUEL INJECTION VALVE

Abstract

Fuel injector (119) for injecting fuel into a combustion chamber (104) of an internal combustion engine, comprising: a first injection port group (410) directed towards a piston (103); a second injection opening group (411) which, in comparison to the first injection opening group, is directed towards a spark plug (120), wherein an injection port partial circle radius (R1) at which the center of injection ports of the first injection port group (410) is located is larger than an injection port partial circle radius (R3) at which the center of injection ports of the second injection port group (411) is located; and a valve body (201) which is raised such that a maximum valve body stroke amount becomes a first stroke amount or a second stroke amount which is less than the first stroke amount, wherein in a case where the maximum valve body stroke amount of the valve body (201) becomes the first stroke amount, a sum of the flow path areas of all injection ports becomes a minimum cross-sectional area of ​​a flow path and in a case where the maximum valve body stroke amount of the valve body (201) becomes the second stroke amount, a flow path area of ​​a seat section becomes the minimum cross-sectional area of ​​the flow path.

Description

Technical field

[0001] The present invention relates to a fuel injection valve used for an internal combustion engine, such as a gasoline engine. State of the art

[0002] In recent years, there has been an increasing demand for gasoline engines in motor vehicles to improve fuel efficiency. Cylinder injection engines have become established as engines with excellent fuel efficiency. In these engines, fuel is injected directly into a combustion chamber, and a mixture of injected fuel and intake air is ignited and exploded by a spark plug. Cylinder injection engines allow for precise timing of injection, enabling fuel injection during the intake stroke. They effectively utilize both homogeneous combustion, where a highly homogeneous mixture is circulated and burned, and stratified combustion, where fuel is injected during the compression stroke to create and burn a partially concentrated fuel mixture near the spark plug.Therefore, it is possible to select optimal combustion according to the operating conditions, which contributes to fuel savings.

[0003] When controlling the air-fuel mixture, it is important to control the penetration force (penetration depth), which determines the range of the fuel and the flow rate of the injected fuel. For example, patent literature 1 describes a technique that makes it possible to increase the penetration force of the spray mist when the stroke of a fuel injector needle increases, and to decrease the penetration force of the spray mist when the stroke of the needle decreases. However, the technique described in patent literature 1 has the problem that the penetration depths of all injection ports change uniformly. In an engine, there is a requirement to change the penetration depths only in a specific direction. Specifically, the required penetration force of the spray mist directed at the piston varies considerably depending on the operating conditions.When fuel is injected during the intake stroke, the spray towards the piston requires a strong penetrating force to mix adequately with the flow; however, when fuel is injected late in the compression stroke, it is desirable for the penetrating force to be as low as possible to reduce fuel adhesion to the piston, since the fuel injector and piston are in close proximity. On the other hand, it is desirable for the spark plug and fuel injector positions to remain fixed regardless of operating conditions and for the penetrating force of the spray directed towards the spark plug to remain largely unchanged.

[0004] Patent literature 2 discloses a technique for selectively injecting fuel from a group of injection ports with different diameters by providing a plurality of valve elements for opening and closing each of the plurality of injection port groups and an independent control unit for each valve element. The technique described in patent literature 2 can change the penetration depth and flow rate depending on the injection direction, but it suffers from a complex design. Patent literature 3 describes an injection valve equipped with a first and a second electromagnet, which is thereby capable of switching the stroke of a valve needle between a high stroke and a low stroke.Patent literature 4 discloses an injection valve at the tip of which an injection port directed outwards from the valve axis and an injection port directed in the direction of the valve axis are arranged. From the outwardly directed injection port, an injection jet is injected downwards along the inner wall of the cylinder, and from the injection port directed in the direction of the valve axis, an injection jet is injected towards the center of the combustion chamber. List of literature Patent literature Patent literature 1: JP 2017 - 8 860 A Patent literature 2: JP 2016 - 61 176 A Patent literature 3: JP 2008- 45 519 A Patent literature 4: JP 5 696 901 B2 Summary of the invention: Technical problem

[0005] Patent literature 1 describes, for example, a technique that makes it possible to increase the penetration force of the spray mist when the stroke of a needle in the fuel injection valve increases, and to decrease the penetration force of the spray mist when the stroke of the needle decreases. However, the technique described in patent literature 1 has the problem that the penetration depths of all injection orifices change.

[0006] The invention was made with regard to the problems mentioned above; one object of the invention is to provide a fuel injection valve that has a simple design and is capable of selectively controlling the penetration force of the spray mist injected in a piston direction by means of a stroke amount. Solution to the problem

[0007] To solve the above problem, the fuel injection valve according to the invention is a fuel injection valve for injecting fuel into a combustion chamber of an internal combustion engine, comprising a first injection port group directed towards a piston, a second injection port group directed towards a spark plug compared to the first injection port group, wherein an injection port partial circle radius at which the center of injection ports of the first injection port group is located is larger than an injection port partial circle radius at which the center of injection ports of the second injection port group is located;and a valve body which is raised such that a maximum valve body stroke amount becomes a first stroke amount or a second stroke amount which is less than the first stroke amount, wherein in a case where the maximum valve body stroke amount of the valve body becomes the first stroke amount, a sum of the flow path areas of all injection ports becomes a minimum cross-sectional area of ​​a flow path, and in a case where the maximum valve body stroke amount of the valve body becomes the second stroke amount, a flow path area of ​​a seat section becomes the minimum cross-sectional area of ​​the flow path. Advantageous effects of the invention

[0008] According to the invention, in a simple design, the penetration force of the spray mist in one piston direction can be selectively controlled by the stroke length. The remaining configurations, processes, and effects of the invention are described in detail in the following embodiments. Brief description of the drawings Fig. Figure 1 is a diagram illustrating the outline of a configuration of an internal combustion engine according to a first embodiment of the invention. Fig. Figure 2 is a diagram illustrating a fuel injection valve according to the first embodiment of the invention. Fig. Figure 3 is an enlarged cross-sectional view of a lower end section of the fuel injector according to the first embodiment of the invention. Fig. Figure 4 is an enlarged cross-sectional view of the lower end section of the fuel injector at the time of a high stroke according to the first embodiment of the invention. Fig. Figure 5 is an enlarged cross-sectional view of the lower end section of the fuel injector at the time of a small stroke according to the first embodiment of the invention. Fig. Figure 6 is a diagram illustrating the cross-sectional area of ​​the flow path in a flow direction according to the first embodiment of the invention. Fig. Figure 7 is an enlarged cross-sectional view of the lower end section of the fuel injector at the time of a small stroke according to the first embodiment of the invention. Fig. Figure 8 is a diagram illustrating a cross-sectional area of ​​the flow path in the flow direction according to the first embodiment of the invention. Fig. Figure 9 is a diagram illustrating a spray direction of the internal combustion engine according to the first embodiment of the invention. Fig. Figure 10 is a diagram showing the spray direction of the internal combustion engine according to the first embodiment of the invention. Fig. Figure 1 is a diagram showing an arrangement of the injection ports of the fuel injection valve according to the first embodiment of the invention. Fig. Figure 12 is a diagram illustrating an arrangement of the injection ports of the fuel injection valve according to the first embodiment of the invention. Fig. Figure 13 is a diagram illustrating a change in the flow rate corresponding to a stroke amount of the fuel injector according to the first embodiment of the invention. Fig. Figure 14 is a diagram illustrating an arrangement of injection ports of the fuel injection valve according to the first embodiment of the invention. Description of embodiments

[0009] The following describes embodiments according to the invention. First embodiment

[0010] A control device for a fuel injection valve 119 according to a first embodiment of the invention is described below with reference to the Fig. 1 and Fig. 2 described.

[0011] Fig. Figure 1 is a diagram illustrating the outline of a cylinder injection engine configuration. The basic operating principle of the cylinder injection engine is explained with reference to... Fig. 1 described. In Fig. 1. A combustion chamber 104 is formed by a cylinder head 101, a cylinder block 102, and a piston 103 inserted into the cylinder block 102. An intake pipe 105 and an exhaust pipe 106 branch off and are connected to two of them in the direction of the combustion chamber 104. An intake valve 107 is provided at an opening of the intake pipe 105, and an exhaust valve 108 is provided at an opening of the exhaust pipe 106. These valves operate by means of a cam mechanism that opens and closes them.

[0012] The piston 103 is connected to a crankshaft 115 via a connecting rod 114, and a crankshaft angle sensor 116 can detect the engine speed. The speed value is sent to an ECU (engine control unit) 118. A cell motor (not shown) is connected to the crankshaft 115. When the engine is started, the cell motor rotates the crankshaft 115. The cylinder block 102 is equipped with a water temperature sensor 117, which can detect the temperature of the engine coolant (not shown). The engine coolant temperature is sent to the ECU 118.

[0013] Although Fig. Since only one cylinder is described, a manifold (not shown) is provided upstream of the intake manifold 105 to distribute air to each cylinder. An air flow meter and a throttle valve (not shown) are provided upstream of the manifold, and the amount of air drawn into the combustion chamber 104 can be adjusted by opening the throttle valve.

[0014] The fuel is stored in a fuel tank 109 and transported by a feed pump 110 to a high-pressure fuel pump 111. The feed pump 110 increases the fuel pressure to approximately 0.3 MPa and delivers the fuel to the high-pressure fuel pump 111. The pressurized fuel from the high-pressure fuel pump 111 is then delivered to a common rail 112. The high-pressure fuel pump 111 pressurizes the fuel to approximately 30 MPa and delivers the fuel to the common rail pump 112. A fuel pressure sensor 113 is attached to the common rail 112 and detects the fuel pressure. The fuel pressure value is transmitted to the ECU 118.

[0015] Fig. Figure 2 is a diagram showing an example of an electromagnetic fuel injector, specifically fuel injector 119 according to this embodiment. The basic operation of the injection device is described with reference to Fig. 2 described. In Fig. 2 Fuel is supplied from a fuel supply opening 212 and directed into the interior of the fuel injection valve 119. The in Fig. The electromagnetic fuel injector 119 shown in Figure 2 belongs to a normally closed electromagnetic actuation type, and when the coil 208 is not energized, a valve body 201 is pressed by a spring 210 against the seat element 202, which is welded to the nozzle body 204. At this point, the supplied fuel pressure in the cylinder injection fuel injector 119 is in the range of approximately 1 MPa to 50 MPa.

[0016] When the coil 208 is energized by a connector 211, a magnetic flux density is generated in a core (solid core) 207, a yoke 209, and an armature 206, which form a magnetic circuit of an electromagnetic valve. A magnetic attraction is generated between the core 207 and the armature 206, creating a gap. If the magnetic attraction is greater than the compressive force of the spring 210 and the force due to the fuel pressure described above, the valve body 201 is attracted to the core 207 by the armature 206, guided by a guide element 203 and a valve body guide 205, and the valve opens. When the valve opens, a gap is created between the seat element 202 and the valve body 201, and fuel injection begins.When fuel injection begins, the energy specified as fuel pressure is converted into kinetic energy, and the fuel is injected into an injection port open at the lower end section of the fuel injector 119.

[0017] Next, the detailed shape of the valve body 201 will be described with reference to Fig. 3 described. Fig. Figure 3 is an enlarged cross-sectional view of the lower end section of the fuel injector 119 and shows the seat element 202, the valve body 201, and related components. The seat element 202 comprises a valve seat surface 304 and a plurality of injection ports 301. The valve seat surface 304 and the valve body 201 extend axially symmetrically about a valve body central axis 305. When the lift is 0, the valve body 201 is in line contact with the seat element 202 and the valve seat surface 304, and the fuel flow is blocked. When the valve body 201 is set to a specific lift, fuel is injected from the injection port 301 through the gap between the seat element 202 and the valve body 201 along the path indicated by the arrow 311. Part of the fuel flows from the injection port into the bag chamber 302 on the tip side and flows into the injection port from the path indicated by arrow 312.The valve body can be set to a large or small stroke. The valve body position for the large stroke is 201b, and the valve body position for the small stroke is 201a. Additionally, a valve opening pulse applied to the injector 119 can be deactivated before the valve is fully open, so that the valve closes before the stroke reaches its maximum. Again, a variety of maximum stroke values ​​can be set.

[0018] Next, with reference to Fig. 4 describes a flow when the valve body 201 is at a large stroke position 201b. At the time of the large stroke, the flow parallel to an injection port axis 303, as indicated by arrow 320, is strong, and the flow perpendicular to the injection port axis 303 (crossflow) is weak, because a region on the upstream side of the injection port is extensively formed. If the minimum cross-sectional area of ​​the flow is adjusted to correspond to the injection port, the flow is rapidly accelerated in the injection port, and the flow parallel to the injection port axis becomes stronger. Since the penetration force of the spray is increased by the increase in axial velocity in the injection port, a spray with strong penetration force is formed during a large stroke.Furthermore, by setting the minimum cross-sectional area of ​​the flow as the sum of the cross-sectional areas of the injection ports, the flow in the injection ports is rapidly accelerated, and a spray mist with strong penetrating force is formed.

[0019] The flow, in which the valve body 201 is located at the small stroke position 201a, is described with reference to Fig. As described in Figure 5, at the point of the small stroke, the flow (crossflow) in the direction perpendicular to the injection port axis 303 is increased, as indicated by arrow 321, because the flow path upstream of the injection port is narrow. At this point, the flow is rapidly accelerated in the seat section by adjusting the minimum cross-sectional area of ​​the flow onto a seat section A2, and a distinct crossflow perpendicular to the injection port axis 303 is generated. This reduces the axial velocity in the injection port, and a spray mist with weak penetration force is formed.

[0020] As described above, the fuel injector 119, which injects fuel into the combustion chamber of an internal combustion engine (preferably a cylinder injection engine), in this embodiment has a valve body 201 that is lifted such that the maximum valve body lift becomes either a first lift (large lift) or a second lift (small lift), which is smaller than the first lift (large lift). In a case where the maximum valve body lift of the valve body 201 becomes the first lift (large lift), the flow path area of ​​the seat section A2 is larger than the sum of the flow path areas of all injection ports. In a case where the maximum valve body lift of the valve body 201 becomes the second lift (small lift), the flow path area of ​​the seat section A2 is smaller than the sum of the flow path areas of all injection ports.Furthermore, seat section A2 is a section of the seat element 202 that establishes linear contact when the valve body 201 is closed, and the flow path is formed around the circumference when seat section A2 is opened. Additionally, when seat section A2 is opened, the flow path area is defined by a minimum distance Lmin × π between seat section A2 of the seat element 202 and the valve body 201. The flow path area of ​​the injection port 301 is also defined by the minimum flow area of ​​the injection port 301.

[0021] In the fuel injection valve 119 of this embodiment, the distance between the seat position A2 and the valve body central axis 305 is arranged further away than the distance between an inlet center position A1 of the injection port and the valve body central axis 305. In other words, the distance R1 between the inlet center position A1 of the injection port and an intersection point B1 of the valve body central axis 305 with a line perpendicular to the valve body central axis 305 from the inlet port A1 of the injection port is set such that it is shorter than the distance R2 between the line perpendicular to the valve body central axis 305 and an intersection point B2 of the valve body central axis 305 from the seat position A2.

[0022] Next, the cross-sectional area of ​​the flow path in the direction along the fuel flow is described. Fig. 6(a) is a diagram showing a change in the flow direction of the cross-sectional area of ​​the flow path during the in Fig. The large stroke is illustrated in Figure 4. S1 represents the cross-sectional area of ​​the flow path immediately upstream of the injection port inlet, and S2 represents the cross-sectional area of ​​the flow at the injection port seat. S3 represents the sum of the cross-sectional areas at the injection port inlet, and S4 represents the sum of the cross-sectional areas at the injection port outlet. At the time of the large stroke, the minimum cross-sectional area of ​​the flow path in the flow direction can be adjusted to the cross-sectional area S3 at the injection port inlet. When the minimum cross-sectional area of ​​the flow is adjusted to the cross-sectional area of ​​the injection port, the flow in the injection port is rapidly accelerated, and a spray mist with strong penetrating force is formed.

[0023] Furthermore, the ratio between the cross-sectional area S2 of the flow path at the seat position and the cross-sectional area S1 of the flow path immediately before the inlet of the injection port can be either S1 < S2 or S1 > S2. Additionally, the ratio between the cross-sectional area S3 of the inlet of the injection port and the cross-sectional area S4 of the outlet of the injection port can be either S3 > S4 or S3 < S4.

[0024] Fig. 6(b) illustrates a change in the flow direction of the cross-sectional area of ​​the flow path during the in Fig. The small stroke is illustrated in Figure 5. At the time of the small stroke, the minimum cross-sectional area of ​​the flow path in the flow direction is set to the cross-sectional area S20 of the flow path at the seat position. At this time, the flow in the seat section is accelerated and gradually decelerated with an increase in the downstream cross-sectional area. This means that by setting S20 < S10, the flow downstream of the seat section is gradually decelerated. At the time of the small stroke, if the cross-sectional area S3 of the injection port is set to S10 < S3 with respect to the cross-sectional area S10 of the flow immediately upstream of the injection port inlet, crossflow occurs near the inlet of the injection port, and the penetration force may be weakened. The ratio between S10 and S3 can, for example, be set to 1:2.

[0025] As described above, the fuel injector 119 of this embodiment is configured such that in a case where the maximum valve body stroke of the valve body 201 becomes the first stroke (large stroke), the sum of the flow path areas of all injection ports becomes the minimum cross-sectional area of ​​the flow path, and in a case where the maximum valve body stroke of the valve body 201 becomes the second stroke (small stroke), the flow path area of ​​the seat section 2A becomes the minimum cross-sectional area of ​​the flow path.

[0026] Next, a flow field is described in a case where the injection port is located near the center of the valve body during the small stroke, with reference to Fig. 7 described. Fig. Figure 7 shows a cross-section similar to Fig. 5, where only the position of the injection port is closer to the valve body's central axis 305. The flow velocity of the flow accelerated by the seat section A2 gradually decreases due to the expansion of the cross-sectional area in the flow direction. If the flow is sufficiently slowed from the seat section to the injection port, no crossflow occurs at the inlet of the injection port, and only a velocity in the direction of the injection port axis appears. Since no crossflow occurs even during the large stroke (not shown), the sensitivity to the penetration depth due to the stroke magnitude is reduced.This means that, assuming that the center of the injection port is A3 and that an intersection of the perpendicular line from the center of the injection port to the valve body center axis 305 and the valve body center axis 305 is B3, the length R3 of the line segment connecting A3 and B3 is adjusted to be smaller than R1, as shown in . Fig. Figure 5 illustrates how the sensitivity to a penetration depth can be reduced due to the stroke amount.

[0027] The cross-sectional area of ​​the flow path in the direction along the fuel flow is calculated with reference to Fig. 8 described. Fig. Figure 8(a) illustrates a change in the cross-sectional area of ​​the flow path in the flow direction in a case where the large stroke is set, at the injection port position in Fig. 7. S5 indicates the cross-sectional area of ​​the flow path immediately upstream of the injection port inlet, and S6 indicates the cross-sectional area of ​​the flow at the injection port seat. S7 indicates the sum of the cross-sectional areas at the injection port inlet, and S8 indicates the sum of the cross-sectional areas at the injection port outlet. In the injection port of Fig. 7. The distance between the seating position and the inlet of the injection port is greater than that of Fig. 5, so that the position of the horizontal axis of the in Fig. 8(a) shown inlet of the injection port downstream of the position of the horizontal axis of the inlet of the injection port, which is in Fig. Figure 6(a) shows that by adjusting the minimum cross-sectional area of ​​the flow in the direction of flow so that it is the inlet of the injection port at the time of the large stroke, the flow in the injection port is rapidly accelerated, and cross-flow is unlikely to occur.

[0028] Fig. Figure 8(b) illustrates the cross-sectional area of ​​the flow path in the small lift state at the in Fig. 7. Position of the injection port shown. As in Fig. 6(b) At the time of the small stroke, the minimum cross-sectional area in the flow direction is set to the cross-sectional area S60 of the flow path at the seat position. In this embodiment, the cross-sectional area gradually increases downstream of the seat section in accordance with the flow, and the ratio of the cross-sectional areas S7 and S50 at the inlet of the injection port can be, for example, 10:9. In other words, the flow is sufficiently slowed down before it reaches the inlet of the injection port so that the flow velocity does not change abruptly and crossflow is minimal. Furthermore, by setting S7 and S50 to narrow values, an abrupt deceleration of the velocity during the flow process to the inlet of the injection port does not occur, thus suppressing crossflow.

[0029] This means that by positioning the center of the injection port close to the central axis of the valve body, the sensitivity to crossflow generation due to the stroke is reduced, so that a change in penetration depth hardly occurs. Furthermore, the ratio between the cross-sectional areas can be set to S7 < S50. Even in the case of S7 < S50, the probability of crossflow occurring is lower, and a change in penetration depth due to the stroke is less likely.

[0030] Next, the Fig. 9 and Fig. Ten schematic views of fuel injection into the combustion chamber. In this embodiment, part of the spray injected by the injector 119 forms a spray mist 400 directed towards the piston 103, and part forms a spray mist 401 directed towards a spark plug 120. Since the relative position between the fuel injector 119 and the spark plug 120 is constant regardless of the operating conditions, it is desirable that the penetration of the spray mist 401 also be constant regardless of the operating conditions. On the other hand, the spray mist 400 is directed towards the piston, and the relationship between the fuel injector 119 and the piston 103 at the time of fuel injection varies considerably depending on the injection start time.For example, in a case where the fuel is injected, for instance, in the latter half of the compression stroke, the relative distance between the fuel injector 119 and the piston 103 is reduced, so that it is desirable that the penetration depth of the spray mist directed in the piston direction is shallow, as by the spray mist 402 in . Fig. Figure 10 illustrates this. Furthermore, a high penetration depth is required in a case where the fuel is evenly distributed in the cylinder while overcoming the airflow in the combustion chamber. On the other hand, a shallow penetration depth is desirable to reduce fuel adhesion to the cylinder wall during start-up.

[0031] The Fig. 11 and Fig. Figure 12 illustrates the circumferential arrangement of the inlet of the injection port when viewed from the flow-intensive side in the fuel injection valve 119 of this embodiment. In this embodiment, the injection port group 410, in which the center of the injection ports is located on a radius R1, is referred to as the first injection port group, and the injection port group 411, in which the center of the injection ports is located on a radius R3, is referred to as the second injection port group. This means that the spray injected from injection port group 410 is directed towards the piston 103, and the spray injected from injection port group 411 is directed towards the spark plug 120. However, the configuration is as shown in Figure 12. Fig. Figure 12 shows that the center position of each inlet of the injection port does not necessarily have to coincide completely with radius R1 or radius R3 and may be arranged so that it is slightly offset.

[0032] However, it is assumed that the relationship R1 > R3 is established. Furthermore, in this embodiment, the centers of the injection ports of the first injection port group (injection port group 410) are formed near the seat section A2, where the valve body 202 is located with respect to the centers of the injection ports of the second injection port group (injection port group 411).

[0033] This means that, compared to the first injection port group (injection port group (410)) in the fuel injector valve 119 of this embodiment, the first injection port group (injection port group 410) is directed towards the piston 103 and the second injection port group (injection port group 411) is directed towards the spark plug 120. The partial circle radius R1 of the injection port, at which the center of the injection ports of the first injection port group (injection port group 410) is located, is configured such that it is larger than the partial circle radius of the injection port R3, at which the center of the injection ports of the second injection port group (injection port group 411) is located.

[0034] As in the Fig. 4 and Fig. As illustrated in Figure 5, in the first injection port group (injection port group 410), where the center of the injection ports is located on radius R1, the strength of the crossflow changes depending on the stroke length, and the penetration depth also changes. This means that by adjusting the first injection port group (injection port group 410) to direct the spray towards the piston 103, the penetration of the spray mist towards the piston 103 can be controlled according to the operating conditions. However, it is not necessary for all injection ports of the first injection port group (injection port group 410) to be directed towards the piston 103, and some injection ports among the injection port groups belonging to the first injection port group (injection port group 410) may be directed towards the piston 103.

[0035] As in Fig. As shown in Figure 7, the second injection port group (injection port group 411), where the center of the injection ports is located on radius R3, has low sensitivity to the penetration depth due to the stroke amount. This means that by adjusting the second injection port group (injection port group 411) to point towards spark plug 120, the penetration depth in the direction of spark plug 120 can be kept constant depending on the operating conditions. However, it is not necessary for all injection ports of the second injection port group (injection port group 411) to be oriented towards the spark plug, and some injection ports among the injection port groups belonging to the second injection port group (injection port group 411) may be oriented towards spark plug 120.

[0036] According to this embodiment, the difference between the penetration depth of the spray mist between the large stroke and the small stroke is configured such that it is greater in the first injection port group (injection port group 410) than in the second injection port group (injection port group 411). This configuration makes it possible to selectively control the penetration depth in the piston direction by the stroke length.

[0037] As described above, the first injection port group (injection port group 410) and the second injection port group (injection port group 411), which is oriented in the spark plug direction, are provided, and the pitch circle radius R1 of the injection port, at which the center of the injection ports of the first injection port group (injection port group 410) is located, is configured to be larger than the injection port pitch circle radius R3 of the injection port, at which the center of the injection ports of the second injection port group (injection port group 411) is located. Thus, the penetration depth in the piston direction can be selectively controlled by the stroke amount.

[0038] Furthermore, the uniformity of the air-fuel mixture during the intake stroke can be increased by controlling the lift amount during intake stroke injection so that it is greater than the lift amount during compression stroke injection, while appropriately reducing piston adhesion during the compression stroke. This means that, in the case of intake stroke injection, the valve body 201 is raised such that the maximum valve body lift becomes the first lift amount (large lift amount), and in the case of compression stroke injection, the valve body is raised by the second lift amount (small lift amount), which is less than the first lift amount (large lift amount).

[0039] In this embodiment, as in Fig. Figure 11 shows that the injection port group 410 of the first injection port group is arranged continuously in the circumferential direction, and the injection port group 410 of the second injection port group is arranged continuously in the circumferential direction. Furthermore, as shown in Fig. Figure 11 shows a cross-section orthogonal to the axis of the valve body. All injection ports of the first injection port group (injection port group 410) are arranged in a region 1 with respect to a straight line X passing through the center. All injection ports of the second injection port group (injection port group 411) are arranged such that they are located in a region 2 opposite the single region 1 with respect to the straight line X. This configuration allows the flow into the injection ports to be symmetrical and suppresses spray mist dispersion.

[0040] As in Fig. As shown in Figure 14, the injection ports of the first injection port group (injection port group 410) and the injection ports of the second injection port group (injection port group 411) can be arranged alternately in the circumferential direction. By adjusting the inclination of the injection ports in the specified direction, the injection direction of the spray mist can be aligned towards the piston 103 or towards the spark plug 120. Furthermore, the alternating arrangement of the ports can increase the distance between the spray mist and reduce interference between the spray mist.

[0041] Next, a change in the flow rate due to the stroke amount will be calculated with reference to the Fig. 11 and Fig. 13 described. In this embodiment, the cross-sectional area of ​​the injection ports of the first injection port group (injection port group 410) is adjusted to be larger than the cross-sectional area of ​​the injection ports of the second injection port group (injection port group 411). Furthermore, in the Fig. 11 and Fig. 12. The cross-sectional areas of the injection ports of the first injection port group (injection port group 410) and the second injection port group (injection port group 411) are equal. If the areas are different, the cross-sectional area of ​​the injection ports is circular, and the injection port diameter of the smallest injection port among the injection ports of the first injection port group (injection port group 410) is configured such that it is desirablely larger than the largest injection port diameter among the injection ports of the second injection port group (injection port group 411). Furthermore, it is desirable that all injection ports of the first injection port group (injection port group 410) have the same injection port diameter.If the stroke is large, the minimum cross-sectional area of ​​the flow path is the sum of the cross-sectional areas of the injection ports, so that the ratio of the cross-sectional areas of the injection ports to the flow rate becomes the ratio. This means that the cross-sectional area of ​​the injection ports of the first injection port group (injection port group 410) directed towards the piston 103 is set so that it is larger than the cross-sectional area of ​​the injection ports of the second injection port group (injection port group 411) directed towards the spark plug 120, so that the flow rate of the spray mist towards the piston can be increased.

[0042] On the other hand, if the stroke is small, the amount of fuel flowing into the injection ports in the first injection port group (injection port group 410) decreases due to the influence of cross-flow. This means, as in Fig. Figure 13 shows that the flow rate of the first injection port group (injection port group 410) is significantly reduced at small strokes compared to large strokes. In the second injection port group (injection port group 411), the fuel flow rate does not change significantly depending on the stroke, as the fuel flowing into the injection ports due to the stroke is not very sensitive.

[0043] This means that the cross-sectional area of ​​the injection port of the first injection port group (injection port group 410) directed towards the piston is set larger than the cross-sectional area of ​​the injection port of the second injection port group (injection port group 411) directed towards the spark plug, so that the flow rate of the spray mist can only be controlled in the direction of the piston by the stroke.

[0044] This reduces the fluctuation in the flow rate of the spray mist directed towards the spark plug, thus improving the stability of the ignition.

[0045] Furthermore, the injection port axis (303 in Fig. 5) the injection port of the first injection port group (injection port group 410) is adjusted so that it forms a larger angle with the valve body center axis (305 in Fig. 5) compared to the injection opening axis (303 in Fig. 5) the injection port of the second injection port group (injection port group 411). With this configuration, the separation of the first injection port group at the time of the small stroke can be promoted and the sensitivity to the stroke amount can be further increased.

[0046] Furthermore, the cross-sectional area of ​​all injection ports in each injection port group does not have to be constant, and a maximum injection port cross-sectional area belonging to the first injection port group can be set so that it is larger than a minimum injection port cross-sectional area belonging to the second injection port group. This makes it possible to finely adjust the spray pattern for each discharge direction.

[0047] Furthermore, in this embodiment, the cross-sectional area of ​​the injection opening is circular, and the injection opening diameter of the smallest injection opening among the injection openings of the first injection opening group is set so that it is larger than the injection opening diameter of the largest injection opening among the injection openings of the second injection opening group, so that a desired effect can be obtained.

[0048] However, the cross-sectional shape of each injection opening does not necessarily have to be circular and can, for example, have a conical or elliptical shape. Reference symbol list 101 Cylinder head 102 cylinder block 103 pistons 104 Combustion chamber 105 Intake manifold 106 Exhaust pipe 107 Inlet valve 108 Exhaust valve 109 Fuel tank 110 Feed pump 111 High-pressure fuel pump 112 Common Rail 113 Fuel pressure sensor 114 Connecting rod 115 Crankshaft 116 Crank angle sensor 117 Water temperature sensor 118 ECU 119 Fuel injector 120 Spark plug 201 Valve bodies 201a Valve body position in the low-lift state 201b Valve body position in the large stroke state 202 Seating element 203 Guide element 204 nozzle bodies 205 Valve body guide 206 anchors 207 core 208 coil 209 yoke 210 spring 211 connectors 212 Fuel supply opening 301 Injection port 302 Sack chamber 303 Central axis of the injection opening 304 Valve seat surface 305 Valve body center axis 311 Inflow from the seat section 312 Inflow from the sack chamber 320 inflow at large lift 321 Inflow at low lift (crossflow) 400 spray mist directed at the piston with high penetration depth 401 Spray mist directed at the spark plug 402 Spray mist directed at the piston with shallow penetration depth 410 injection ports belonging to the first injection port group 411 injection ports belonging to the second injection port group

Claims

[1] Fuel injection valve (119) for injecting fuel into a combustion chamber (104) of an internal combustion engine, comprising: a first injection port group (410) directed towards a piston (103); a second injection opening group (411) which, in comparison to the first injection opening group, is directed towards a spark plug (120), wherein an injection port partial circle radius (R1) at which the center of injection ports of the first injection port group (410) is located is larger than an injection port partial circle radius (R3) at which the center of injection ports of the second injection port group (411) is located; and a valve body (201) which is raised such that a maximum valve body stroke amount becomes a first stroke amount or a second stroke amount which is less than the first stroke amount, wherein in a case where the maximum valve body stroke amount of the valve body (201) becomes the first stroke amount, a sum of the flow path areas of all injection ports becomes a minimum cross-sectional area of ​​a flow path and in a case where the maximum valve body stroke amount of the valve body (201) becomes the second stroke amount, a flow path area of ​​a seat section becomes the minimum cross-sectional area of ​​the flow path. [2] Fuel injection valve (119) according to claim 1, wherein a maximum injection port cross-sectional area of ​​the injection ports belonging to the first injection port group (410) is larger than a minimum injection port cross-sectional area of ​​the injection ports belonging to the second injection port group (411). [3] Fuel injection valve (119) according to claim 2, wherein a cross-sectional area of ​​the injection opening is circular, an injection opening diameter of the smallest injection opening among the injection openings of the first injection opening group (410) is larger than an injection opening diameter of the largest injection opening among the injection openings of the second injection opening group (411). [4] Fuel injection valve (119) according to claim 1, wherein the injection ports of the first injection port group (410) are arranged continuously in a circumferential direction, and the injection ports of the second injection port group (411) are arranged continuously in a circumferential direction. [5] Fuel injection valve (119) according to claim 1, wherein an injection opening axis of the injection openings of the first injection opening group (410) forms a larger angle with a valve body central axis compared to an injection opening axis of the injection openings of the second injection opening group (411). [6] Fuel injection valve (119) according to claim 1, wherein a stroke amount during an intake stroke injection is controlled such that it is greater than a stroke amount during a compression stroke injection, [7] Fuel injection valve (119) according to claim 1, wherein in a case in which all injection ports of the first injection port group (410) are arranged in a region with respect to a straight line passing through a center on a cross-section orthogonal to an axis direction of the valve body (201), all injection ports of the second injection port group (411) are arranged in a region opposite the one region with respect to the straight line in a case in which all injection ports of the second injection port group (411) are arranged. [8] Fuel injection valve (119) according to claim 3, wherein all injection ports of the first injection port group (410) have the same diameter. [9] Fuel injection valve (119) according to claim 1, wherein the center of the injection ports of the first injection port group (410) is closer to a seat section on which the valve body sits than the center of the injection ports of the second injection port group (411). [10] Fuel injection valve (119) according to claim 1, wherein the difference in the penetration depth of the spray mist between a large stroke and a small stroke in the first injection opening group (410) is greater than in the second injection opening group (411).

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