JPWO2020148821A1 - Fuel injection device - Google Patents

Abstract

A plurality of swivel chambers (18a, 18b) that allow fuel to flow into the central portion from the valve seat opening (12b) and are joined to the end portions to give a swirling force to the fuel on the upstream end surface of the injection hole plate (13). It has a fuel passage (17) through which fuel flows out, and injection holes (14a, 14b) are opened in the swivel chambers (18a, 18b), and the swivel chambers (18a, 18b) and the injection holes (14a, 14b) are opened. ) Is point-symmetrically arranged with respect to the center (17c) of the fuel passage, and the central axis (40) of the fuel passage is offset with respect to the center (12c) of the valve seat opening. The direction of the main stream (30a, 30b) of the fuel flow flowing into the injection hole (14a, 14b) from the opening (12b) through the fuel passage (17) is in two directions, a direction away from the injection hole and a direction toward the injection hole. It is configured to be.

Description

The present application relates to a fuel injection device.

In recent years, emission regulations for internal combustion engines installed in automobiles have been tightened, and as part of this, there is a demand for atomization of fuel spray injected from the fuel injection device of internal combustion engines. Various studies have been made on the method for atomizing.

The conventional fuel injection device disclosed in Patent Document 1 includes a valve body that moves in response to a control signal from an internal combustion engine control module, a valve seat on which the valve body sits or separates, and a valve for a fuel flow direction. It is equipped with a fuel injector nozzle installed in the immediate vicinity on the downstream side of the seat, and the fuel injector nozzle communicates with a plurality of groove-shaped flow paths that communicate with each other at the center and on the downstream side of each flow path. A plurality of vortex chambers are provided, and each vortex chamber is provided with an injection hole for ejecting fuel.

According to the conventional fuel injection device disclosed in Patent Document 1, the fuel that has flowed from the valve seat to the central portion of the fuel injection nozzle flows evenly into a plurality of groove-shaped flow paths and is rectified in the flow paths. Then, it flows into the vortex chamber and flows into the injection hole while generating a swirling flow. The fuel that has flowed into the injection hole maintains a swirling flow inside the injection hole and forms a thin liquid film along the inner wall of the injection hole. The thin liquid film formed on the inner wall of the injection hole is atomized by being injected from the injection hole into the combustion chamber of the internal combustion engine in a hollow conical shape, and the atomization of the fuel is promoted.

JP-A-2002-98028

In recent years, in a method of injecting fuel in an intake port of an internal combustion engine, there are an increasing number of cases where fuel is injected in the intake stroke of an internal combustion engine for the purpose of improving fuel efficiency. As is well known, in the fuel injection in the intake stroke, the fuel is injected with the intake valve open, and the fuel spray is directly flowed into the combustion chamber of the internal combustion engine to enhance the vaporization cooling effect in the combustion chamber. This is a method that makes it possible to improve fuel efficiency by improving knock resistance and increasing the compression ratio of the internal combustion engine.

The conventional fuel injection device disclosed in Patent Document 1 described above has good fuel atomization performance, but has a small penetration force. Therefore, when fuel is injected in the intake stroke of an internal combustion engine, the fuel injection device has a small penetration force. Due to the influence of the intake flow generated in the intake port, the fuel spray is flowed to the ceiling side of the intake port, and a part of the fuel spray adheres to the inner wall surface of the ceiling part of the intake port, and the inflow amount of the fuel spray into the combustion chamber. May decrease. For this reason, the vaporization and cooling effect in the combustion chamber becomes insufficient, the knock resistance cannot be improved, and the compression ratio of the internal combustion engine cannot be increased, so that a sufficient fuel efficiency improvement effect cannot be obtained. was there.

Further, in the above-mentioned conventional fuel injection device, even in the case of exhaust stroke injection in which fuel is injected with the intake valve closed, the influence of intake pulsation generated between each intake port of the multi-cylinder internal combustion engine , And when the injection amount is large and the injection period is long, the required amount of fuel cannot be injected in the exhaust stroke and the latter half of the fuel injection operation shifts to the intake stroke, which is affected by the intake flow and fuel. There is a problem that the spray is flowed to the ceiling of the intake port and easily adheres to the inner wall of the ceiling of the intake port, which hinders the improvement of fuel efficiency.

The present application has been made to solve the above-mentioned problems in the conventional fuel injection device, and can reduce the adhesion of fuel to the inner wall of the intake port and promote the improvement of fuel efficiency. It is an object of the present invention to provide an injection device.

The fuel injection device according to the present application is
It has a valve body for opening and closing the valve seat, and by receiving an operation signal from the control device to operate the valve body, the fuel passes between the valve body and the valve seat seat portion, and then the valve seat downstream side. It is a fuel injection device that is injected from a plurality of injection holes provided in the injection hole plate mounted on the valve seat opening of the above.
On the upstream end surface of the injection hole plate, a plurality of swirl chambers are arranged on the radial outer side of the valve seat opening to apply a swirling force to the fuel, and the fuel flows into the central portion from the valve seat opening. The swivel chamber joined to the end has a fuel passage for flowing out fuel, and the swivel chamber is provided with the injection hole for injecting fuel to the outside.
When the upstream end face of the injection hole plate is viewed from the upstream side in the central axis direction of the valve seat opening, the plurality of swivel chambers and the injection hole are arranged point-symmetrically with respect to the center of the fuel passage. , The central axis of the fuel passage is offset with respect to the center of the valve seat opening.
Of the plurality of injection holes, at least one injection hole is provided offset to the center side of the valve seat opening with respect to the central axis of the fuel passage, and at least one injection hole is provided in the fuel passage. It is provided offset to the central axis on the opposite side of the center of the valve seat opening.
It is characterized by that.

The fuel injection device according to the present application has a valve body for opening and closing the valve seat, and by receiving an operation signal from the control device to operate the valve body, fuel is transferred between the valve body and the valve seat seat portion. After passing, the fuel injection device is a fuel injection device in which fuel is injected from a plurality of injection holes provided in the injection hole plates mounted on the valve seat openings on the downstream side of the valve seat. A plurality of swivel chambers are arranged on the radial outer side of the valve seat opening to apply a swivel force to the fuel, and the fuel flows into the central portion from the valve seat opening and the fuel is supplied to the swivel chamber joined to the end portion. It has a fuel passage that flows out, has the injection hole that opens in the swivel chamber and injects fuel to the outside, and has an upstream end face of the injection hole plate from the upstream side in the central axis direction of the valve seat opening. When viewed, the plurality of swivel chambers and the injection holes are arranged point-symmetrically with respect to the center of the fuel passage, and the central axis of the fuel passage is offset with respect to the center of the valve seat opening. Of the plurality of injection holes, at least one injection hole is provided so as to be offset toward the center side of the valve seat opening with respect to the central axis of the fuel passage, and at least one injection hole is the fuel passage. Provided is a fuel injection device capable of reducing fuel adhesion to the intake port wall and promoting improvement of fuel efficiency because it is provided offset to the central axis of the valve seat opening on the opposite side to the center of the valve seat opening. can do.

It is a vertical sectional view of the fuel injection apparatus according to Embodiment 1. FIG. It is a vertical sectional view of a part of the fuel injection apparatus according to Embodiment 1. FIG. It is a cross-sectional view which looked at the cross section along the line AA of FIG. 2 from the direction of an arrow. It is explanatory drawing of the upstream side end face of the injection hole plate of the fuel injection apparatus according to Embodiment 1. FIG. It is explanatory drawing of the upstream side end face of the injection hole plate of the fuel injection apparatus according to Embodiment 2. FIG. It is a vertical sectional view of a part of the fuel injection apparatus according to Embodiment 3. It is a cross-sectional view of the cross section along the line BB of FIG. 6 seen from the direction of an arrow. It is explanatory drawing which shows the upstream side end face of the injection hole plate of the fuel injection apparatus by Embodiment 3. FIG. It is explanatory drawing in the case where the fuel injection device according to Embodiment 4 is installed in the intake port of an internal combustion engine. It is explanatory drawing of the upstream side end face of the injection hole plate of the fuel injection apparatus according to Embodiment 4 which looked at the cross section along the CC line of FIG. 9 from the direction of an arrow.

Embodiment 1.
1 is a vertical cross-sectional view of the fuel injection device according to the first embodiment, FIG. 2 is a vertical cross-sectional view of a part of the fuel injection device according to the first embodiment, and FIG. 3 is a cross section taken along the line AA of FIG. It is a cross-sectional view seen from the direction of an arrow. In FIGS. 1, 2, and 3, the fuel injection device 1 is composed of a solenoid device 4 and a valve device 9. The solenoid device 4 is provided as a resin frame 71 having flanges at both ends in the axial direction, a coil 7 wound around the outer periphery of the frame 71, and a yoke arranged on the outer periphery of the coil 7. Metal housing 5, core 6 as a metal fixed iron core inserted into the inner peripheral surface of the frame body 71 and the inner peripheral surface of the housing 5, coil 7, frame body 71, core 6 and housing 5 It is composed of a resin-made insulating outer cover 41 embedded inside.

The valve device 9 includes a valve body 10, an amateur 8 made of a metal that is a magnetic material, a valve seat 12, a valve holder 11, and a jet hole plate 13. The valve holder 11 is fixed to the core 6 by welding after the one end in the axial direction is press-fitted into the outer peripheral portion of the one end in the axial direction of the core 6. The valve holder 11 is provided with an annular guide portion 11a protruding from the inner peripheral surface on the inner peripheral surface on the one end side in the axial direction. The amateur 8 is press-fitted into one end of the valve body 10 in the axial direction, and then fixed to the valve body 10 by welding. The amateur 8 is slidably supported in the axial direction by the guide portion 11a of the valve holder 11, and when sucked by the core 6 as described later, the amateur 8 slides in the axial direction and the end face 8a of the amateur 8 is the core. It abuts on the end face of 6. The ball 15 is fixed to the other end of the valve body 10 in the axial direction by welding, and has a flat surface 15a formed by a plurality of chamfers.

The valve seat 12 is formed in a hollow cylindrical shape in which one end in the axial direction is open and the other end is closed by the end wall 121. Inside the valve seat 12, the above-mentioned ball 15 fixed by welding to the other end of the valve body 10 in the axial direction is arranged so as to be movable in the axial direction. An annular seat portion 12a on which the ball 15 is seated is formed on the inner surface of the end wall portion 121 of the valve seat 12. Further, a valve seat opening 12b penetrating the end wall portion 121 is provided at the center of the end wall portion 121 of the valve seat 12. The valve seat opening 12b is closed when the ball 15 is seated on the seat portion 12a of the valve seat 12, and is released from the blockage when the ball 15 is separated from the seat portion 12a to separate the inside and the outside of the valve seat 12. Communicate.

The dish-shaped injection hole plate 13 has its upstream end face fixed to the downstream side of the valve seat 12 by welding. The welded portion 50 indicates the welded portion. The peripheral edge of the valve seat 12 and the peripheral edge of the injection hole plate 13 are fixed in contact with the inner peripheral portion of the other end in the axial direction of the valve holder 11.

As shown in FIG. 3, the injection hole plate 13 has a fuel passage connected to a first swivel chamber 18a, a second swivel chamber 18b, a first swivel chamber 18a, and a second swivel chamber 18b. 17, a first injection hole 14a penetrating the injection hole plate 13 in the plate thickness direction, and a second injection hole 14b are provided. The first swivel chamber 18a, the second swivel chamber 18b, and the fuel passage 17 are formed by recessing the upstream end surface of the injection hole plate 13, and the bottom surfaces thereof are substantially coplanar and continuous. It is configured to do. Details of the configuration of the injection hole plate 13 will be described later.

The first injection hole 14a is formed in the central portion of the first swivel chamber 18a, and the second injection hole 14b is formed in the central portion of the second swivel chamber 18b. The center 13c of the injection hole plate 13 and the center 12c of the valve seat opening 12b of the valve seat 12 are located on the central axis X of the fuel injection device 1. One end of the compression spring 16 inserted inside the core 6 is fixed to the core 6, and the other end is in contact with one end in the axial direction of the valve body 10, so that the valve body 10 is always attached to the valve seat 12. Pressing in the direction.

Next, the operation of the fuel injection device according to the first embodiment will be described. When an operation signal is sent from the control device (not shown) of the internal combustion engine to the drive circuit (not shown) of the fuel injection device 1, a current is passed through the coil 7 of the fuel injection device 1, and the amateur 8, the core 6, and the core 6 A magnetic flux is generated in the magnetic circuit composed of the housing 5 and the valve holder 11, and the amateur 8 is attracted to the core 6 side against the pressing force of the compression spring 16 and moves. When the amateur 8 is sucked to the core 6 side and moves, the ball 15 of the valve body 10 fixed to the amateur 8 is separated from the seat portion 12a of the valve seat 12, and the valve seat opening 12b is caused by the ball 15. Freed from blockage.

When the valve seat opening 12b is released from the blockage by the ball 15, the high-pressure fuel filled inside the valve holder 11 reaches the flat surface 15a of the ball 15 of the valve body 10 and the inner peripheral surface of the valve seat 12. It flows into the central portion of the fuel passage 17 of the injection hole plate 13 through the gap between the gaps, the gap between the seat portion 12a of the valve seat 12 and the outer peripheral surface of the ball 15, and the valve seat opening 12b. .. The fuel that has flowed into the central portion of the fuel passage 17 splits from the central portion of the fuel passage 17 and flows into the first swivel chamber 18a and the second swivel chamber 18b, and the first injection from the first swivel chamber 18a. It is injected into the intake port of the internal combustion engine through the hole 14a, and at the same time, is injected from the second swivel chamber 18b into the intake port of the internal combustion engine through the second injection hole 14b.

Next, when a stop signal for stopping the fuel injection operation is sent from the control device of the internal combustion engine to the drive circuit of the fuel injection device 1, the current of the coil 7 is cut off, and the amateur 8, the core 6, the housing 5, and the valve The magnetic flux of the magnetic circuit composed of the holder 11 is reduced, and the amateur 8 slides on the surface of the guide portion 11a of the valve holder 11 and moves in the direction of the valve seat 12 due to the pressing force of the compression spring 16. As a result, the ball 15 of the valve body 10 sits on the seat portion 12a of the valve seat 12 and closes the valve seat opening 12b. As a result, the injection of fuel from the first injection hole 14a and the second injection hole 14b is stopped.

Here, the configuration of the injection hole plate 13 will be described in more detail. FIG. 4 is an explanatory view of the upstream end surface of the injection hole plate of the fuel injection device according to the first embodiment. As shown in FIG. 4, on the upstream end surface of the injection hole plate 13, a first swivel chamber 18a and a second swivel chamber 18b that apply a swivel force to the fuel are radially outside the valve seat opening 12b. Is formed in.

A first injection hole 14a is provided in the central portion of the first swivel chamber 18a, and a second injection hole 14b is provided in the central portion of the second swivel chamber 18b. Further, a fuel passage 17 having a central portion facing the valve seat opening 12b is provided on the upstream end surface of the injection hole plate 13. The fuel flowing out from the valve seat opening 12b flows into the fuel passage from the central portion of the fuel passage 17 and then diverges into the first swivel chamber 18a and the second swivel chamber 18b joined to both ends of the fuel passage 17. It is configured to do.

Further, when the upstream end surface of the injection hole plate 13 is viewed from the upstream side of the central axis X passing through the center of the valve seat opening 12b, the center 12c of the valve seat opening 12b and the center 13c of the injection hole plate 13 are aligned. Arranged to match. The first swivel chamber 18a and the second swivel chamber 18b are arranged so as to be point-symmetrical with respect to the center 17c of the fuel passage 17. Further, the first injection hole 14a and the second injection hole 14b are formed so as to be point-symmetric with respect to the center 17c of the fuel passage 17.

Further, the central shaft 40 of the fuel passage 17 is provided so as to be offset by a predetermined amount with respect to the center 12c of the valve seat opening and the center 13c of the injection hole plate 13. As a result, the first injection hole 14a provided in the first swivel chamber 18a is offset by a predetermined amount toward the center 12c of the valve seat opening 12b with respect to the central axis 40 of the fuel passage 17. The second injection hole 14b provided in the second swivel chamber 18b is offset by a predetermined amount with respect to the central axis 40 of the fuel passage 17 on the side opposite to the center 12c of the valve seat opening 12b.

The fuel that has flowed from the valve seat opening 12b of the valve seat 12 to the upstream end surface of the injection hole plate 13 radiates from the center 12c of the valve seat opening 12b to the center of the fuel passage 17, but the first Since the first injection hole 14a provided in the swivel chamber 18a is offset in the direction of the center 12c of the valve seat opening 12b with respect to the central axis 40 of the fuel passage 17, the first injection hole 14a is provided through the fuel passage 17. The main flow 30a of the flow of fuel flowing into the first injection hole 14a provided in the swivel chamber 18a is the side wall 17w of the fuel passage 17 opposite to the first injection hole 14a with respect to the center 17c of the fuel passage 17. Flows in the direction of. For this reason, it becomes difficult for fuel to directly enter the first injection hole 14a, a first swirling flow 30a1 with strong fuel is generated inside the first swivel chamber 18a, and the penetrating force is small and the fuel is sufficiently atomized. A spray is formed and the fuel spray is injected from the first injection hole 14a into the intake port of the internal combustion engine.

On the other hand, the second injection hole 14b provided in the second swivel chamber 18b is offset from the central axis 40 of the fuel passage 17 to the side opposite to the center 12c of the valve seat opening 12b, so that the fuel The main stream 30b of the fuel flow flowing in the direction of the second injection hole 14b provided in the second swivel chamber 18b through the passage 17 flows in the direction of the second injection hole 14b, and flows in the direction of the second injection hole 14b. Fuel can easily flow directly into 14b. Therefore, a second swirl flow 30b1 weaker than the above-mentioned first swirl flow 30a1 is generated inside the second swirl chamber 18b, and a fuel spray having a large penetrating force is formed, and this fuel spray is the second. It is injected from the injection hole 14b into the intake port of the internal combustion engine.

In this way, the fuel that has flowed into the swirl chamber from the valve seat opening flows into the injection hole while generating a swirling flow, and the swirling flow is maintained even inside the injection hole, so that the fuel is thin along the inner wall of the injection hole. A liquid film is formed, and atomization of the fuel is promoted by injecting a thin liquid film from the injection hole in a hollow conical shape.

In the fuel injection device according to the first embodiment, in one injection hole plate, the direction of the main flow of the fuel flow flowing into the injection hole provided in the swirl chamber through the fuel passage from the valve seat opening is directed toward the injection hole. It is possible to set in two directions away from the injection hole, and it is possible to generate two types of swirling flow, weak swirling flow and strong swirling flow in the swirling chamber. It is possible to form two types of fuel sprays with good fuel sprays. Therefore, even when fuel injection is performed when there is an intake flow in the intake port, it becomes difficult for the fuel spray to flow due to the intake flow, and it is possible to reduce the adhesion of the fuel spray to the intake port wall. Therefore, it is possible to improve the direct entry rate of the fuel spray into the combustion chamber, enhance the vaporization / cooling effect in the combustion chamber, improve the knock resistance, increase the compression ratio, and improve the fuel efficiency.

On the other hand, in the case of the conventional fuel injection device disclosed in Patent Document 1 described above, the center of the valve seat opening and the center of a plurality of fuel passages provided on the upstream end surface of the injection hole plate and extending radially are located. Consistent, the mainstream direction of the fuel flow from the valve seat opening into each fuel passage and towards the injection hole is substantially parallel to the central axis of the fuel passage and is the same in each swivel chamber. A swirling flow of fuel of such strength is generated, and a fuel spray having the same penetrating force is injected from each injection hole. Therefore, the above-mentioned effect cannot be obtained by the fuel injection device according to the first embodiment of the present application.

Further, in a fuel atomization type fuel injection device using a general swirling flow of fuel, when fuel sprays having different penetrating powers are formed by one injection hole plate, the fuel sprays having different penetrating powers are used. It is necessary to form injection holes, swivel chambers, fuel passages, etc. having different shapes corresponding to each in one injection hole plate, which complicates the fuel flow path structure and deteriorates workability. According to the fuel injection device according to the first embodiment, the injection hole, the swivel chamber, and the fuel passage corresponding to the different penetration forces of the fuel spray have the same shape, and the central axis of the fuel passage is set with respect to the center of the valve seat opening. Since it is only necessary to offset, the fuel flow path structure can be simplified and the workability can be improved.

Embodiment 2.
Next, the fuel injection device according to the second embodiment of the present application will be described. In the fuel injection device according to the first embodiment, two injection holes are provided on the upstream end surface of the injection hole plate, but in the fuel injection device according to the second embodiment, four injection holes are provided on the upstream end surface of the injection hole plate. Is provided. FIG. 5 is an explanatory view of the upstream end surface of the injection hole plate of the fuel injection device according to the second embodiment.

In FIG. 5, the first fuel passage 17 and the second fuel passage 171 are provided on the upstream end surface of the injection hole plate 13 so as to intersect each other at a common center 17c and orthogonal to each other. ing. A first swivel chamber 18a is connected to one end of the first fuel passage 17, and a second swivel chamber 18b is connected to the other end of the first fuel passage 17. A third swivel chamber 18c is connected to one end of the second fuel passage 171 and a fourth swivel chamber 18d is connected to the other end of the second fuel passage 171. The first swivel chamber 18a, the second swivel chamber 18b, the third swivel chamber 18c, and the fourth swivel chamber 18d are formed on the radial outer side of the valve seat opening 12b, respectively.

The first fuel passage 17, the second fuel passage 171 and the first swivel chamber 18a, the second swivel chamber 18b, the third swivel chamber 18c, and the fourth swivel chamber 18d are described above. It is formed by recessing the upstream end surface of the injection hole plate 13, and the bottom surfaces of the injection hole plates 13 are formed so as to form substantially the same plane and be continuous.

A first injection hole 14a penetrating the injection hole plate 13 in the plate thickness direction is opened in the central portion of the first swivel chamber 18a, and an injection hole plate 13 is provided in the central portion of the second swivel chamber 18b. A second injection hole 14b penetrating in the plate thickness direction is opened, and a third injection hole 14c penetrating the injection hole plate 13 in the plate thickness direction is opened in the central portion of the third swivel chamber 18c. A fourth injection hole 14d that penetrates the injection hole plate 13 in the plate thickness direction is opened in the central portion of the swivel chamber 18d of No. 4.

Further, when the upstream end surface of the injection hole plate 13 is viewed from the upstream side of the central axis X passing through the center 12c of the valve seat opening 12b, the center 12c of the valve seat opening 12b and the center 13c of the injection hole plate 13 are one. I am doing it. The first swivel chamber 18a and the second swivel chamber 18b are arranged so as to be point-symmetric with respect to the common center 17c of the first fuel passage 17 and the second fuel passage 171. The injection holes 14a and the second injection holes 14b are arranged so as to be point-symmetric with respect to the common center 17c of the first fuel passage 17 and the second fuel passage 171. Further, the third swivel chamber 18c and the fourth swivel chamber 18d are arranged so as to be point-symmetric with respect to the common center 17c of the first fuel passage 17 and the second fuel passage 171 so as to be point-symmetrical. The injection holes 14c and the fourth injection holes 14d are arranged so as to be point-symmetric with respect to the common center 17c of the first fuel passage 17 and the second fuel passage 171.

Further, the central shaft 40 of the first fuel passage 17 and the central shaft 401 of the second fuel passage 171 are provided so as to be offset by a predetermined amount with respect to the center 12c of the valve seat opening 12b. Further, the first injection hole 14a provided in the first swivel chamber 18a and the third injection hole 14c provided in the third swivel chamber 18c are respectively the central axis 40 of the first fuel passage 17. The second fuel passage 171 is provided so as to be offset by a predetermined amount in the direction of the center 12c of the valve seat opening 12b with respect to the central axis 401 of the second fuel passage 171 and is provided in the second swivel chamber 18b. The injection hole 14b and the fourth injection hole 14d provided in the fourth swivel chamber 18d are relative to the central axis 40 of the first fuel passage 17 and the central axis 401 of the second fuel passage 171, respectively. , The valve seat opening 12b is provided so as to be offset by a predetermined amount in the direction opposite to the center 12c.

The fuel that has flowed from the valve seat opening 12b to the upstream end surface of the injection hole plate 13 radiates from the center 12c of the valve seat opening 12b to the central portion of the first fuel passage 17 and the second fuel passage 171. The first injection hole 14a provided in the first swivel chamber 18a is offset in the direction of the center 12c of the valve seat opening 12b with respect to the central axis 40 of the first fuel passage 17. Therefore, the main stream 30a of the flow of fuel flowing into the first injection hole 14a provided in the first swivel chamber 18a through the first fuel passage 17 is directed with respect to the central axis 40 of the first fuel passage 17. It flows in the direction of the side wall 17w of the first fuel passage 17 opposite to the first injection hole 14a. For this reason, it becomes difficult for fuel to directly enter the first injection hole 14a, a first swirling flow 30a1 with strong fuel is generated inside the first swivel chamber 18a, and the penetrating force is small and the fuel is sufficiently atomized. A spray is formed and injected from the first injection hole 14a into the intake port of the internal combustion engine.

Similarly, the third injection hole 14c provided in the third swivel chamber 18c is offset in the direction of the center 12c of the valve seat opening 12b with respect to the central axis 401 of the second fuel passage 171. Therefore, the main stream 30c of the fuel flow flowing into the third injection hole 14c provided in the third swivel chamber 18c through the second fuel passage 171 is directed with respect to the central axis 401 of the second fuel passage 171. It flows in the direction of the side wall 171w of the second fuel passage 171 opposite to the third injection hole 14c. For this reason, it becomes difficult for fuel to directly enter the third injection hole 14c, a third swirl flow 30c1 with strong fuel is generated inside the third swivel chamber 18c, and the penetrating force is small and the fuel is sufficiently atomized. A spray is formed and injected from the third injection hole 14c into the intake port of the internal combustion engine.

On the other hand, the second injection hole 14b provided in the second swivel chamber 18b is offset in the direction opposite to the center 12c of the valve seat opening 12b with respect to the central axis 40 of the first fuel passage 17. Therefore, the main stream 30b of the fuel flow flowing in the direction of the second injection hole 14b provided in the second swivel chamber 18b through the first fuel passage 17 faces the direction of the second injection hole 14b. The fuel easily flows directly into the second injection hole 14b. Therefore, a second swirl flow 30b1 weaker than the above-mentioned first swirl flow 30a1 is generated inside the second swirl chamber 18b, and a fuel spray having a large penetrating force is formed from the second injection hole 14b. It is injected into the intake port of an internal combustion engine.

Similarly, the fourth injection hole 14d provided in the fourth swivel chamber 18d is offset with respect to the central axis 401 of the second fuel passage 171 in the direction opposite to the center 12c of the valve seat opening 12b. Therefore, the mainstream 30d of the fuel flow flowing in the direction of the fourth injection hole 14d provided in the fourth swivel chamber 18d through the second fuel passage 171 is directed toward the fourth injection hole 14d. The fuel easily flows directly into the fourth injection hole 14d. Therefore, a fourth swirl flow 30d1 weaker than the above-mentioned third swirl flow 30c1 is generated inside the fourth swirl chamber 18d, and a fuel spray having a large penetrating force is formed from the fourth injection hole 14d. It is injected into the intake port of an internal combustion engine.

As described above, according to the fuel injection device according to the second embodiment, the number of injection holes is four, and two types of fuel sprays having different penetration forces, that is, penetration, are provided on one injection hole plate. It is possible to form two types of fuel sprays, a fuel spray having a large force and a fuel spray having a small penetrating force and being satisfactorily atomized, and the same effect as that of the fuel injection device of the first embodiment can be obtained. Can be done.

Further, the first injection hole 14a and the third injection hole 14c, which form a fuel spray having a small penetrating force and are satisfactorily atomized, are arranged in a mass close to each other and form a fuel spray having a large penetrating force. The second injection hole 14b and the fourth injection hole 14d are arranged in a mass close to each other, and the first injection hole 14a and the third injection hole 14c, the second injection hole 14b and the fourth injection hole 14b are arranged. Since the injection holes 14d of the above are arranged so as to be line-symmetrically separated with respect to the common center 17c of the first fuel passage 17 and the second fuel passage 171. Are less likely to interfere with each other, and deterioration of atomization can be suppressed.

In the fuel injection device according to the second embodiment described above, the case where the number of injection holes is four is shown, but the number of injection holes may be further increased, and a plurality of fuel sprays having different penetrating power may be formed. The same effect as described above can be obtained, the injection flow rate can be expanded by increasing the number of injection holes, and even when the required flow rate for the fuel injection device is a large flow rate, it is possible to cope with it.

Embodiment 3.
Next, the fuel injection device according to the third embodiment of the present application will be described. In the fuel injection device according to the first embodiment described above, the center of the fuel passage does not coincide with the center of the injection hole plate, and the center of the fuel passage is provided so as to be offset from the center of the injection hole plate. In the fuel injection device according to the third embodiment, when the upstream end face of the injection hole plate is viewed from the upstream side of the central axis passing through the center of the valve seat opening, the center of the injection hole plate and the center of the fuel passage are aligned. The center of the injection hole plate and the center of the fuel passage are offset from the center of the valve seat opening. Other configurations are the same as those of the fuel injection device according to the first embodiment.

FIG. 6 is a vertical cross-sectional view of a part of the fuel injection device according to the third embodiment, FIG. 7 is a cross-sectional view of a cross section along the line BB of FIG. It is explanatory drawing of the upstream side end face of the injection hole plate of the fuel injection device by 3. In FIGS. 6, 7, and 8, the center 17c of the fuel passage 17 coincides with the center 13c of the injection hole plate 13, and the first injection holes 14a and the first injection holes 14a provided in the injection hole plate 13 are provided. The injection hole 14b, the first swivel chamber 18a, the second swivel chamber 18b, and the fuel passage 17 of the second are arranged point-symmetrically with respect to the center 13c of the injection hole plate and the center 17c of the fuel passage. The injection hole plate 13 is formed in a flat disk shape, and the outer diameter of the injection hole plate 13 is formed to be smaller than the outer diameter of the valve seat 12.

In the above-described first embodiment, the injection hole plate 13 is formed in a dish shape, but in the third embodiment, the injection hole plate 13 is formed in a flat disk shape. Therefore, the production of the injection hole plate 13 Alternatively, there is a merit that processing becomes easy. Further, in the third embodiment, the outer diameter of the injection hole plate 13 is formed smaller than the outer diameter of the valve seat 12. Therefore, even if the valve seat 12 and the injection hole plate 13 are not strictly concentrically fixed, the outer edge portion of the injection hole plate 13 does not come into contact with the inner wall of the valve holder 11, and the valve seat 12 and the valve holder 11 do not come into contact with each other. It can be easily assembled with.

Further, according to the third embodiment, the center 13c of the injection hole plate 13 and the center 17c of the fuel passage 17 are arranged with respect to the center 12c of the valve seat opening 12b provided on the central axis X of the valve seat 12. The fuel passages 17 are arranged offset by a predetermined amount in the direction orthogonal to the central axis 40.

Therefore, the fuel that has flowed from the valve seat opening 12b of the valve seat 12 to the upstream end surface of the injection hole plate 13 radiates from the center 12c of the valve seat opening 12b to the center of the fuel passage 17. Since the first injection hole 14a provided in the first swivel chamber 18a is offset in the direction of the center 12c of the valve seat opening 12b with respect to the central axis 40 of the fuel passage 17, the first injection hole 14a passes through the fuel passage 17. The main stream 30a of the flow of fuel flowing into the first injection hole 14a provided in the swivel chamber 18a of 1 is the fuel passage 17 opposite to the first injection hole 14a with respect to the central axis 40 of the fuel passage 17. It flows in the direction of the side wall 17w of the. For this reason, it becomes difficult for fuel to directly enter the first injection hole 14a, a first swirling flow 30a1 with strong fuel is generated inside the first swivel chamber 18a, and the penetrating force is small and the fuel is sufficiently atomized. A spray is formed and injected from the first injection hole 14a into the intake port of the internal combustion engine.

On the other hand, since the second injection hole 14b provided in the second swivel chamber 18b is offset from the central axis 40 of the fuel passage 17 in the direction opposite to the center 12c of the valve seat opening 12b. , The main stream 30b of the flow of fuel flowing in the direction of the second injection hole 14b provided in the second swivel chamber 18b through the fuel passage 17 flows in the direction of the second injection hole 14b, and the second Fuel can easily flow directly into the injection hole 14b. Therefore, a second swirl flow 30b1 weaker than the above-mentioned first swirl flow 30a1 is generated inside the second swirl chamber 18b, and a fuel spray having a large penetrating force is formed from the second injection hole 14b. It is injected into the intake port of an internal combustion engine.

As described above, according to the fuel injection device according to the third embodiment, the fuel flow flowing from the valve seat opening 12b into the first injection hole 14a and the second injection hole 14b is the same as in the case of the first embodiment. In addition, it is possible to set the main flow 30b in the direction toward the injection hole and the main flow 30a in the direction away from the injection hole, and the fuel spray has a large penetration force and the fuel spray has a small penetration force and is sufficiently atomized. It is possible to form two types of fuel sprays, and the same effect as that of the first embodiment can be obtained.

Further, the fuel injection device according to the third embodiment changes the shape of the fuel passage 17, the first swivel chamber 18a, and the second swivel chamber 18b formed on the upstream end surface of the injection hole plate 13. Instead, by shifting the center of the valve seat 12 and the center of the injection hole plate 13 and fixing them to each other, the fuel can be valved only by adjusting the offset amount of the central axis 40 of the fuel passage 17 with respect to the center 12c of the valve seat opening. Since the direction of the fuel flow from the seat opening 12b to the first injection hole 14a and the second injection hole 14b can be adjusted, the optimum magnitude of the penetrating force corresponding to various internal combustion engines for fuel spraying can be adjusted. Can be adjusted to. Therefore, in a atomization type fuel injection device using a general swirling flow, a swirling flow is applied to the fuel formed on the upstream end surface of the injection hole plate when adjusting the penetrating force of the fuel spray. Compared to adjusting the flow path shape of the injection hole, swivel chamber, fuel passage, etc., the design man-hours required for the adjustment can be reduced, and the cost of changing the injection hole plate mold is not required, which reduces the cost. can do.

Embodiment 4.
Next, the fuel injection device according to the fourth embodiment of the present application will be described. FIG. 9 is an explanatory view when the fuel injection device according to the fourth embodiment is installed in the intake port of the internal combustion engine, and FIG. 10 is the third embodiment in which a cross section taken along the line CC of FIG. 9 is viewed from the direction of an arrow. It is explanatory drawing which shows the upstream end face of the injection hole plate of the fuel injection device by. In FIG. 9, the fuel injection device 1 according to any one of the above-described first to third embodiments is mounted on the ceiling 70b of the intake port 70 communicating with the combustion chamber 60 of the internal combustion engine. Fuel is injected from the fuel injection device 1 toward the intake valve 80 of the engine.

In the case of intake stroke injection in which fuel is injected in the intake stroke of an internal combustion engine, an intake flow 90 is generated inside the intake port 70 from the upstream side to the downstream side in the fuel flow direction. Since the penetration force of the fuel spray is small in the injection device, the fuel spray is flowed to the ceiling 70b of the intake port 70 by the intake flow 90 and adheres to the inner wall surface of the ceiling 70b, and the amount of fuel flowing into the combustion chamber 60. Therefore, the vaporization and cooling effect in the combustion chamber 60 becomes insufficient, the knock resistance is not improved, and the compression ratio cannot be increased, so that a sufficient fuel efficiency improving effect cannot be sufficiently obtained.

In the fuel injection device according to the fourth embodiment, as shown in FIG. 10, the first injection hole 14a offset in the direction of the center 12c of the valve seat opening 12b with respect to the central axis 40 of the fuel passage 17 It is arranged so as to be on the side Y1 close to the bottom 70a of the intake port with respect to the center 17c of the fuel passage 17, and is offset in the direction opposite to the center 12c of the valve seat opening 12b with respect to the central axis 40 of the fuel passage 17. The second injection hole 14b is arranged on the side Y2 close to the ceiling portion 70b of the intake port with respect to the center 17c of the fuel passage 17. Therefore, the first fuel spray F1 having a small penetrating force and being sufficiently atomized is injected from the first injection hole 14a toward the bottom 70a side of the intake port 70, and the penetrating force is large from the second injection hole 14b. The second fuel spray F2 is injected toward the ceiling portion 70b side of the intake port 70.

According to the fourth embodiment, the intake flow 90 generated in the case of the intake stroke injection causes the first fuel spray F1 having a small penetrating force and sufficiently atomized to flow to the ceiling portion 70b of the intake port 70 and adhere to the wall surface. This can be suppressed by the second fuel spray F2, which has a large penetration force.

Although the present application describes various exemplary embodiments and examples, the various features, embodiments, and functions described in one or more embodiments are applications of a particular embodiment. It is not limited to, but can be applied to embodiments alone or in various combinations. Therefore, innumerable variations not illustrated are envisioned within the scope of the techniques disclosed in the present application. For example, it is assumed that at least one component is modified, added or omitted, and further, at least one component is extracted and combined with the components of other embodiments.

The fuel injection device according to the present application can be used in the field of an internal combustion engine and thus in the field of the automobile industry.

1 Fuel injection device, 4 Solenoid device, 5 Housing, 6 core, 7 coil, 8 amateur, 9 valve device, 10 valve body, 11 valve holder, 12 valve seat, 12b valve seat opening, 13 injection hole plate, 14a 1 injection hole, 14b second injection hole, 14c third injection hole, 14d fourth injection hole, 15 balls, 16 compression springs, 17 fuel passages, 17 first fuel passages, 171 second fuel passages. , 18a 1st swivel chamber, 18b 2nd swivel chamber, 18c 3rd swivel chamber, 18d 4th swivel chamber, 50 welds, 60 combustion chamber, 70 intake port, 80 intake valve, 90 intake flow, F1 1st fuel spray, F2 2nd fuel spray

Claims (4)

It has a valve body for opening and closing the valve seat, and by receiving an operation signal from the control device to operate the valve body, the fuel passes between the valve body and the valve seat seat portion, and then the valve seat downstream side. It is a fuel injection device that is injected from a plurality of injection holes provided in the injection hole plate mounted on the valve seat opening of the above.
On the upstream end surface of the injection hole plate, a plurality of swirl chambers are arranged on the radial outer side of the valve seat opening to apply a swirling force to the fuel, and the fuel flows into the central portion from the valve seat opening. The swivel chamber joined to the end has a fuel passage for flowing out fuel, and the swivel chamber is provided with the injection hole for injecting fuel to the outside.
When the upstream end face of the injection hole plate is viewed from the upstream side in the central axis direction of the valve seat opening, the plurality of swivel chambers and the injection hole are arranged point-symmetrically with respect to the center of the fuel passage. , The central axis of the fuel passage is offset with respect to the center of the valve seat opening.
Of the plurality of injection holes, at least one injection hole is provided offset to the center side of the valve seat opening with respect to the central axis of the fuel passage, and at least one injection hole is provided in the fuel passage. A fuel injection device characterized in that it is provided so as to be offset from the central axis to the opposite side of the center of the valve seat opening. Of the plurality of injection holes, at least two injection holes that are offset toward the center side of the valve seat opening with respect to the central axis of the fuel passage, and the valve seat opening with respect to the central axis of the fuel passage. The fuel injection device according to claim 1, wherein at least two injection holes offset to the opposite side of the center of the portion are arranged close to each other in a mass. When the upstream end face of the injection hole plate is viewed from the upstream side in the central axis direction of the valve seat opening, the center of the injection hole plate and the center of the fuel passage coincide with each other.
The fuel injection device according to claim 1 or 2, wherein the center of the injection hole plate is offset with respect to the center of the valve seat opening. The fuel injection device installed on the ceiling side of the intake port communicating with the combustion chamber of the internal combustion engine.
Of the plurality of injection holes, the injection hole offset to the center side of the valve seat opening with respect to the central axis of the fuel passage is arranged on the bottom side of the intake port on the injection hole plate.
The claim is characterized in that the injection hole offset to the central axis of the fuel passage on the opposite side of the center of the valve seat opening is arranged on the ceiling side of the intake port on the injection hole plate. The fuel injection device according to any one of 1 to 3.

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