JP2017020394A - Fuel injection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel injection device capable of effectively reducing wetting by a fuel, of a wall surface of a member connected to an internal combustion engine or a member configuring the internal combustion engine.SOLUTION: A nozzle bottom portion 12 has specific shape outer wall surfaces 61, 62 formed into concentric circular shapes to be continuously arranged toward a radial outer side of an opening formation outer wall surface 51. The specific shape outer wall surface 61 connected to an outer edge end of the opening formation outer wall surface 51 at an inner edge end, is formed so that an outline on a cross-section by a virtual plane VP1 including axis Ax2 of a nozzle cylindrical portion 11 is raised at a nozzle cylindrical portion 11 side to "a virtual orthogonal straight line VA1 orthogonal to the axis Ax2 and passing an outer edge end of the opening formation outer wall surface 51". The specific shape outer wall surface 62 connected to the outer edge end of the specific shape outer wall surface 61 at an inner edge end is formed so that an outline on a cross-section by the virtual plane VP1 is raised to a nozzle cylinder portion 11 side to "a virtual extension straight line VE1 obtained by extending the outline of the specific shape outer wall surface 61 at a radial inner side to a radial outer side".SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fuel injection device that injects and supplies fuel to an internal combustion engine.

  Conventionally, a fuel injection device that injects fuel and supplies it to an internal combustion engine is known. For example, the fuel injection device disclosed in Patent Document 1 is applied to a direct injection internal combustion engine that directly injects fuel into a combustion chamber.

JP 2009-281346 A

  By the way, depending on the mounting position and angle of the fuel injection device in the combustion chamber, the fuel injection amount, and the like, the injected fuel spray may adhere to the combustion chamber and the wall surface of the piston. Therefore, the combustion chamber and the wall surface of the piston may get wet with the fuel, hindering good combustion of the injected fuel, or causing an increase in unburned fuel and a cold loss. As a result, fuel consumption may be deteriorated.

  In the fuel injection device of Patent Document 1, the injection hole is formed to be inclined with respect to the axis of the needle. When fuel is injected from such an injection hole, the effect | action which draws in the air around a spray to a spray direction arises by the pressure change accompanying injection. When the drawn-in air collides with the spray, the momentum of the spray is converted into the momentum of the air, and the momentum of the spray is lost, so that wetting of the combustion chamber and the piston wall by the fuel is reduced.

  Further, in the fuel injection device of Patent Document 1, a tapered outer wall surface is formed on the radially outer side of a planar outer wall surface on which an opening on the outlet side of the injection hole is formed. For this reason, when fuel is injected, it is considered that the action of drawing the air around the spray in the spray direction is relatively large. However, in order to further reduce the wettability of the combustion chamber and the piston wall by the fuel, it is necessary to further devise the shape around the injection hole of the fuel injection device.

  The present invention has been made in view of the above-described problems, and provides a fuel injection device capable of effectively reducing the wettability of a wall surface of a member connected to the internal combustion engine or a member constituting the internal combustion engine. is there.

The fuel injection device of the present invention includes a nozzle portion and a needle.
The nozzle part includes a nozzle cylinder part having a fuel passage inside, a nozzle bottom part that closes one end of the nozzle cylinder part, an end face of the nozzle bottom part on the nozzle cylinder part side, and an end face opposite to the nozzle cylinder part. And a valve seat formed in an annular shape around the nozzle hole on the nozzle cylinder side of the nozzle bottom.
The needle is provided inside the nozzle tube portion of the nozzle portion so that one end can contact the valve seat and can reciprocate in the axial direction. Open and close.

  In the present invention, the nozzle bottom portion is formed at a position where the axis of the nozzle cylinder portion passes and is formed with an opening-forming outer wall surface on which an opening on the outlet side of the nozzle hole is formed, and an outer edge of the opening-forming outer wall surface and the nozzle cylinder portion. A plurality of concentrically shaped outer wall surfaces are formed concentrically so as to be continuously arranged toward the radially outer side of the opening-formed outer wall surface between the outer wall surfaces.

  Of the plurality of specific shape outer wall surfaces, the specific shape outer wall surface in which the inner edge end is connected to the outer edge end of the opening forming outer wall surface has a contour in a cross section by a virtual plane including the axis line of the nozzle cylinder portion. It is formed so as to rise to the nozzle tube side with respect to a “virtual orthogonal straight line passing through the outer edge of the outer wall surface where the opening is formed”.

  In addition, among the plurality of specific shape outer wall surfaces, the specific shape outer wall surface in which the inner edge end is connected to the outer edge end of the other specific shape outer wall surface has a contour in a cross section by the imaginary plane, Is formed so as to rise to the nozzle tube side with respect to a “virtual extension straight line extending outward in the radial direction”.

  In the present invention, a plurality of concentric outer walls having a specific shape are formed on the radially outer side of the opening-forming outer wall surface on which the opening on the outlet side of the nozzle hole is formed. The plurality of specific-shaped outer wall surfaces are all formed so as to rise toward the nozzle cylinder side with respect to the virtual orthogonal straight line or the virtual extension straight line. Therefore, when injecting fuel from the nozzle hole, it is possible to effectively draw air in the vicinity of the specific-shaped outer wall surface in the fuel spray direction. Thereby, it is possible to suppress the adhesion of fuel spray to the wall surface of a member connected to the internal combustion engine such as an intake port or a member constituting the internal combustion engine such as a cylinder or a piston. Therefore, wetting of the wall surface with fuel can be effectively reduced. As a result, fuel consumption can be improved.

In another fuel injection device of the present invention, the nozzle bottom portion is formed at a position where the axis of the nozzle cylinder portion passes, and an opening forming outer wall surface on which an opening on the outlet side of the nozzle hole is formed, and an outer edge of the opening forming outer wall surface Between the end and the outer wall surface of the nozzle tube portion, it has a specific shape outer wall surface formed in a concave shape or a flat shape that is recessed toward the nozzle tube portion side.
Then, the outer wall surface of the specific shape is such that the contour in the cross section of the virtual plane including the axis of the nozzle cylinder part rises on the nozzle cylinder side with respect to the “virtual orthogonal straight line passing through the outer edge of the opening-formed outer wall surface perpendicular to the axis line” Is formed.

  In the present invention, a concave or planar specific-shaped outer wall surface that is recessed toward the nozzle tube portion side is formed on the radially outer side of the opening-forming outer wall surface in which the opening on the outlet side of the nozzle hole is formed. Therefore, when injecting fuel from the nozzle hole, it is possible to effectively draw air in the vicinity of the specific-shaped outer wall surface in the fuel spray direction. Thereby, it is possible to suppress the adhesion of fuel spray to the wall surface of a member connected to the internal combustion engine such as an intake port or a member constituting the internal combustion engine such as a cylinder or a piston. Therefore, wetting of the wall surface with fuel can be effectively reduced. As a result, fuel consumption can be improved.

Sectional drawing which shows the fuel-injection apparatus by 1st Embodiment of this invention. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 1st Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 2nd Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 3rd Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 4th Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 5th Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 6th Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 7th Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction. (A) is sectional drawing which shows the nozzle hole vicinity of the fuel-injection apparatus by 8th Embodiment of this invention, (B) is the figure which looked at (A) from the arrow B direction.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. Note that, in a plurality of embodiments, substantially the same components are denoted by the same reference numerals, and description thereof is omitted.
(First embodiment)

  A fuel injection device according to a first embodiment of the present invention is shown in FIG. The fuel injection device 1 is applied to, for example, a gasoline engine as an internal combustion engine (not shown), and injects gasoline as fuel and supplies it to the engine. The fuel injection device 1 is provided, for example, so that fuel can be injected into an intake port connected to each cylinder of an engine (not shown). That is, the engine to which the fuel injection device 1 of the present embodiment is applied is a port injection type engine.

The fuel injection device 1 includes a nozzle unit 10, a housing 20, a needle 30, a movable core 40, a fixed core 41, a spring 43, a coil 44, and the like.
The nozzle portion 10 is made of a metal such as martensitic stainless steel. The nozzle unit 10 is subjected to a quenching process so as to have a predetermined hardness. As shown in FIG. 1, the nozzle portion 10 includes a nozzle cylinder portion 11, a nozzle bottom portion 12, an injection hole 13, and a valve seat 14.

  The nozzle cylinder portion 11 is formed in a cylindrical shape. The nozzle bottom 12 closes one end of the nozzle cylinder 11. The nozzle hole 13 connects the surface of the nozzle bottom portion 12 on the nozzle tube portion 11 side, that is, the inner wall, and the surface opposite to the nozzle tube portion 11, that is, the outer wall, so that fuel is injected. A plurality of nozzle holes 13 are formed in the nozzle bottom 12. In the present embodiment, eight nozzle holes 13 are formed at equal intervals in the circumferential direction of the nozzle bottom 12 (see FIG. 2B). The valve seat 14 is formed in an annular shape around the nozzle hole 13 on the nozzle cylinder portion 11 side of the nozzle bottom portion 12.

The housing 20 includes a first cylinder member 21, a second cylinder member 22, a third cylinder member 23, an inlet portion 24, a filter 25, and the like.
The first cylinder member 21, the second cylinder member 22, and the third cylinder member 23 are all formed in a substantially cylindrical shape. The first cylinder member 21, the second cylinder member 22, and the third cylinder member 23 are arranged so as to be coaxial (axis Ax1) in the order of the first cylinder member 21, the second cylinder member 22, and the third cylinder member 23. Connected.

The 1st cylinder member 21 and the 3rd cylinder member 23 are formed, for example with magnetic materials, such as ferritic stainless steel, and the magnetic stabilization process is performed. The first cylinder member 21 and the third cylinder member 23 have a relatively low hardness. On the other hand, the second cylindrical member 22 is formed of a nonmagnetic material such as austenitic stainless steel, for example. The hardness of the second cylinder member 22 is higher than the hardness of the first cylinder member 21 and the third cylinder member 23.
An end portion of the nozzle cylinder portion 11 opposite to the nozzle bottom portion 12 is connected to the inner side of the end portion of the first cylinder member 21 opposite to the second cylinder member 22. The 1st cylinder member 21 and the nozzle part 10 are connected by welding, for example.

  The inlet portion 24 is formed in a cylindrical shape from a magnetic material such as ferritic stainless steel. The inlet portion 24 is provided so that one end thereof is connected to the end portion of the third cylindrical member 23 opposite to the second cylindrical member 22. In this embodiment, the inlet part 24 is integrally formed of the same material as the third cylinder member 23 (see FIG. 1).

A fuel passage 100 is formed inside the housing 20. The fuel passage 100 is connected to the injection hole 13. That is, the nozzle cylinder part 11 forms the fuel passage 100 inside. A pipe (not shown) is connected to the inlet 24 on the side opposite to the third cylinder member 23. As a result, the fuel from the fuel supply source flows into the fuel passage 100 via the pipe. The fuel passage 100 guides fuel to the nozzle hole 13.
The filter 25 is provided inside the inlet portion 24. The filter 25 collects foreign matters in the fuel flowing into the fuel passage 100.

The needle 30 is formed in a bottomed cylindrical shape with a metal such as martensitic stainless steel. The needle 30 is quenched so as to have a predetermined hardness. The hardness of the needle 30 is set substantially equal to the hardness of the nozzle portion 10.
The needle 30 is accommodated in the housing 20 so as to reciprocate in the fuel passage 100 in the direction of the axis Ax1 of the housing 20. The needle 30 has a seat portion 31, a first hole portion 32, a second hole portion 33, and the like.
The seat portion 31 is formed at the end portion on the bottom side of the needle 30 and can contact the valve seat 14.

  The nozzle part 10 has a guide part 15 that protrudes inwardly from the inner wall of the nozzle cylinder part 11. The needle 30 has an outer wall slidable with the inner wall of the guide portion 15. Thereby, the guide part 15 can guide the reciprocation of the needle 30 in the axis Ax1 direction.

  The first hole 32 is formed to connect the inner wall and the outer wall of the needle 30 in the radial direction. In the present embodiment, the first hole 32 is formed in a circular shape. Further, a total of two first hole portions 32 are formed so as to face each other. The second hole 33 is formed on the valve seat 14 side with respect to the first hole 32 so as to connect the inner wall and the outer wall of the needle 30 in the radial direction. In the present embodiment, the second hole portion 33 is formed in a long hole shape. A total of four second holes 33 are formed at equal intervals in the circumferential direction of the needle 30. As a result, the fuel inside and outside the needle 30 can flow through the first hole 32 and the second hole 33.

  The needle 30 opens and closes the injection hole 13 when the seat portion 31 is separated (separated) from the valve seat 14 or abuts (sits) the valve seat 14. Hereinafter, the direction in which the needle 30 is separated from the valve seat 14 is referred to as the valve opening direction, and the direction in which the needle 30 contacts the valve seat 14 is referred to as the valve closing direction.

  The movable core 40 is formed in a substantially cylindrical shape by a magnetic material such as ferritic stainless steel. The movable core 40 is subjected to a magnetic stabilization process. The hardness of the movable core 40 is relatively low and is substantially equal to the hardness of the first cylindrical member 21 and the third cylindrical member 23 of the housing 20.

  The movable core 40 is provided coaxially with the needle 30 so that the inner side of one end is connected to the outer wall of the end opposite to the valve seat 14 of the needle 30. In the present embodiment, the movable core 40 and the needle 30 are connected by welding. Therefore, the movable core 40 can reciprocate in the axis Ax1 direction within the housing 20 together with the needle 30. The space inside the needle 30 and the space inside the movable core 40 are connected.

  The movable core 40 has a projecting portion 401 formed so as to project annularly outward from the outer wall at the end opposite to the needle 30 in the radial direction. The protrusion 401 is slidable on the outer wall of the second cylindrical member 22 of the housing 20. Therefore, the movable core 40 is guided to reciprocate in the direction of the axis Ax1 by the inner wall of the second cylindrical member 22. That is, the needle 30 and the movable core 40 are guided by the guide portion 15 and the second cylindrical member 22 to reciprocate in the direction of the axis Ax1 in the fuel passage 100. In addition, the movable core 40 has a spring seat portion 402 formed so as to protrude in an annular shape radially inward from the inner wall.

The fixed core 41 is formed in a substantially cylindrical shape by a magnetic material such as ferritic stainless steel. The fixed core 41 is subjected to a magnetic stabilization process. The fixed core 41 has a relatively low hardness and is approximately equal to the hardness of the movable core 40. The fixed core 41 is provided on the opposite side of the movable core 40 from the valve seat 14. The fixed core 41 is provided inside the housing 20 so that the outer wall is connected to the inner walls of the second cylinder member 22 and the third cylinder member 23. The end surface of the fixed core 41 on the valve seat 14 side can contact the end surface of the movable core 40 on the fixed core 41 side.
A cylindrical adjusting pipe 42 is press-fitted inside the fixed core 41.

  The spring 43 is, for example, a coil spring, and is provided between the adjusting pipe 42 inside the fixed core 41 and the spring seat portion 402 of the movable core 40. One end of the spring 43 is in contact with the adjusting pipe 42. The other end of the spring 43 is in contact with the spring seat 402. The spring 43 can urge the movable core 40 together with the needle 30 toward the valve seat 14, that is, in the valve closing direction. The biasing force of the spring 43 is adjusted by the position of the adjusting pipe 42 with respect to the fixed core 41.

  The coil 44 is formed in a substantially cylindrical shape, and is provided so as to surround the outer side in the radial direction of the second cylindrical member 22 and the third cylindrical member 23 in the housing 20. A cylindrical holder 45 is provided outside the coil 44 in the radial direction so as to cover the coil 44. The holder 45 is made of a magnetic material such as ferritic stainless steel.

  The coil 44 generates a magnetic force when electric power is supplied (energized). When a magnetic force is generated in the coil 44, a magnetic circuit is formed in the fixed core 41, the movable core 40, the first cylindrical member 21, the holder 45, and the third cylindrical member 23. Thereby, a magnetic attractive force is generated between the fixed core 41 and the movable core 40, and the movable core 40 is attracted to the fixed core 41 side together with the needle 30. Thereby, the needle 30 moves in the valve opening direction, and the seat portion 31 is separated from the valve seat 14 and opened. As a result, the nozzle hole 13 is opened. Thus, when the coil 44 is energized, it is possible to suck the movable core 40 toward the fixed core 41 and move the needle 30 to the side opposite to the valve seat 14.

  Note that when the movable core 40 is attracted to the fixed core 41 side (valve opening direction) by a magnetic attraction force, the end surface on the fixed core 41 side collides with the end surface of the fixed core 41 on the movable core 40 side. Thereby, the movement of the movable core 40 in the valve opening direction is restricted.

  When energization of the coil 44 is stopped in a state where the movable core 40 is attracted to the fixed core 41 side, the needle 30 and the movable core 40 are urged toward the valve seat 14 by the urging force of the spring 43. As a result, the needle 30 moves in the valve closing direction, the seat portion 31 comes into contact with the valve seat 14 and closes. As a result, the nozzle hole 13 is closed.

  As shown in FIG. 1, the radially outer sides of the inlet portion 24, the third cylindrical member 23, the coil 44, and the holder 45 are molded with resin to form a molded portion 46. A connector portion 47 is formed so as to protrude radially outward from the mold portion 46. The connector portion 47 is insert-molded with a terminal 471 for supplying power to the coil 44.

  The fuel flowing in from the inlet portion 24 flows through the fixed core 41, the adjusting pipe 42, the spring 43, the inside of the needle 30, the second hole portion 33, between the needle 30 and the nozzle portion 10, that is, the fuel passage 100. , Guided to the nozzle hole 13. When the fuel injection device 1 is operated, the periphery of the movable core 40 and the needle 30 is filled with fuel. Further, when the fuel injection device 1 is operated, the fuel flows through the first hole portion 32 of the needle 30. Therefore, the movable core 40 and the needle 30 can smoothly reciprocate in the direction of the axis Ax1 inside the housing 20.

Next, the shape and the like of the nozzle portion 10 will be described in detail based on FIG.
As shown in FIG. 2A, the nozzle bottom portion 12 has an opening forming inner wall surface 50, an opening forming outer wall surface 51, outer walls 61, 62 having specific shapes, and the like.

  The opening forming inner wall surface 50 is formed in a planar shape on the end surface 121 of the nozzle bottom portion 12 on the nozzle tube portion 11 side. The opening forming outer wall surface 51 is formed in a planar shape on the end surface 122 on the opposite side of the nozzle bottom portion 12 from the opening forming inner wall surface 50, that is, on the opposite side of the nozzle bottom portion 12 from the nozzle cylinder portion 11. The opening forming inner wall surface 50 and the opening forming outer wall surface 51 are formed at positions where the axis Ax2 of the nozzle cylinder portion 11 passes. An opening 131 on the inlet side of the nozzle hole 13 is formed in the opening forming inner wall surface 50.

  The opening forming outer wall surface 51 is formed to be circular when viewed from the direction of the axis Ax2 (see FIG. 2B). An opening 132 on the outlet side of the nozzle hole 13 is formed in the opening forming outer wall surface 51. In the present embodiment, the nozzle hole 13 is formed such that the outlet-side opening 132 is positioned on a virtual circle VC1 centered on the axis Ax2 of the nozzle cylinder portion 11.

  In the present embodiment, the nozzle hole 13 is formed such that the central axis CL1 is inclined with respect to the axis Ax2 of the nozzle cylinder portion 11. That is, the angle θa1 formed by the central axis CL1 and the axis Ax2 is larger than zero. Further, the nozzle hole 13 is formed in a tapered shape so that the inner wall is separated from the central axis CL1 as it goes from the opening 131 side to the opening 132 side (see FIG. 2A).

  The specific-shaped outer wall surface 61 and the specific-shaped outer wall surface 62 are continuously arranged toward the radially outer side of the opening-forming outer wall surface 51 between the outer edge of the opening-forming outer wall surface 51 and the outer wall surface of the nozzle cylinder portion 11. It is formed concentrically (see FIGS. 2A and 2B). 2A, the boundary between the specific shape outer wall surface 61 and the specific shape outer wall surface 62, and the boundary between the specific shape outer wall surface 62 and the outer wall surface of the nozzle cylinder portion 11 are indicated by two-dot chain lines. .

  Among the specific shape outer wall surface 61 and the specific shape outer wall surface 62, the specific shape outer wall surface 61 whose inner edge is connected to the outer edge of the opening forming outer wall surface 51 has a contour in a cross section by the virtual plane VP1 including the axis Ax2. It is formed so as to rise to the nozzle cylinder 11 side with respect to a virtual orthogonal straight line VA1 orthogonal to Ax2 and passing through the outer edge of the opening-formed outer wall surface 51 (see FIGS. 2A and 2B).

  Among the specific shape outer wall surface 61 and the specific shape outer wall surface 62, the specific shape outer wall surface 62 whose inner edge is connected to the outer edge of the other specific shape outer wall surface (61) has an outline in a cross section by the virtual plane VP <b> 1. It is formed so as to rise toward the nozzle cylinder portion 11 with respect to a virtual extension straight line VE1 obtained by extending the outline of the specific-shaped outer wall surface 61 on the inner side in the radial direction outward (see FIGS. 2A and 2B).

  In this embodiment, the specific-shaped outer wall surfaces 61 and 62 are formed so that the contour in the cross section by the virtual plane VP1 is linear. Further, the specific-shaped outer wall surfaces 61 and 62 are concentric so as to be continuously arranged toward the radially outer side of the opening forming outer wall surface 51 between the outer edge of the opening forming outer wall surface 51 and the outer wall surface of the nozzle cylinder portion 11. Is formed. That is, the specific-shaped outer wall surfaces 61 and 62 are formed in a curved shape so as to bend in the circumferential direction of the nozzle cylinder portion 11 (see FIGS. 2A and 2B).

  The angle θb1 formed by the virtual straight line VE1 and the virtual straight line VL1 along the specific shape outer wall surface 61 and the axis Ax2 is smaller than the angle θb2 formed by the virtual straight line VL2 along the specific shape outer wall surface 62 and the axis Ax2. Here, the angle θc1 formed by the virtual straight line VL1 and the central axis CL1 is equal to the difference between θb1 and θa1. Further, the angle θc2 formed by the virtual straight line VL2 and the central axis CL1 is equal to the difference between θb2 and θa1 (see FIG. 2A). In the present embodiment, θc1 and θc2 are set to about 90 degrees.

  Further, the angle θd1 formed by the virtual orthogonal straight line VA1 and the virtual straight line VL1, that is, the rising angle of the outer wall surface 61 with respect to the virtual orthogonal straight line VA1 is equal to the angle obtained by subtracting 90 degrees from θb1. Further, the angle θd2 formed by the virtual extension straight line VE1 and the virtual straight line VL2, that is, the rising angle of the specific-shaped outer wall surface 62 with respect to the virtual extension straight line VE1 is equal to the angle obtained by subtracting θb1 from θb2.

  As described above, (1) in the present embodiment, the nozzle portion 10 includes the nozzle cylinder portion 11 having the fuel passage 100 inside, the nozzle bottom portion 12 that closes one end of the nozzle cylinder portion 11, and the nozzle cylinder portion of the nozzle bottom portion 12. 11 is connected to the end surface 122 on the opposite side of the nozzle cylinder 11 and the nozzle hole 13 for injecting fuel in the fuel passage 100, and the nozzle hole 13 on the nozzle cylinder part 11 side of the nozzle bottom 12. A valve seat 14 is formed around the periphery of the valve seat 14.

  One end (seat portion 31) of the needle 30 can be brought into contact with the valve seat 14 and can be reciprocated in the axial direction. The needle 30 is provided inside the nozzle cylinder portion 11 of the nozzle portion 10, and one end is separated from the valve seat 14. Or when it contacts the valve seat 14, the nozzle hole 13 is opened and closed.

  In the present embodiment, the nozzle bottom portion 12 is formed at a position where the axis Ax2 of the nozzle cylinder portion 11 passes, and the opening forming outer wall surface 51 in which the opening 132 on the outlet side of the nozzle hole 13 is formed, and the opening forming outer wall surface 51. Specific outer wall surfaces 61 and 62 formed concentrically so as to be continuously arranged toward the radially outer side of the opening-forming outer wall surface 51 between the outer edge of the nozzle cylinder portion 11 and the outer wall surface of the nozzle cylinder portion 11. .

  And among the specific shape outer wall surface 61 and the specific shape outer wall surface 62, the specific shape outer wall surface 61 whose inner edge end connects to the outer edge end of the opening forming outer wall surface 51 has a contour in a cross section by the virtual plane VP1 including the axis Ax2. “A virtual orthogonal straight line VA1 perpendicular to the axis Ax2 and passing through the outer edge of the opening-forming outer wall surface 51” is formed so as to rise toward the nozzle cylinder 11 side.

  Further, among the specific shape outer wall surface 61 and the specific shape outer wall surface 62, the specific shape outer wall surface 62 whose inner edge is connected to the outer edge of the other specific shape outer wall surface (61) has a contour in a cross section by the virtual plane VP1. It is formed so as to rise to the nozzle cylinder portion 11 side with respect to the “virtual extension straight line VE1 obtained by extending the contour of the outer wall surface 61 of the specific shape radially inside” radially outward.

  In the present embodiment, concentric outer walls 61 and 62 having concentric shapes are formed on the radially outer side of the opening-forming outer wall surface 51 where the opening 132 on the outlet side of the nozzle hole 13 is formed. The specific-shaped outer wall surfaces 61 and 62 are both formed so as to rise toward the nozzle cylinder portion 11 with respect to the virtual orthogonal straight line VA1 or the virtual extension straight line VE1. Therefore, when fuel is injected from the nozzle hole 13, the air in the vicinity of the specific-shaped outer wall surfaces 61 and 62 can be effectively drawn in the fuel spray direction (see FIGS. 2A and 2B). Thereby, the adhesion of the fuel spray to the wall surface of the member connected to the engine such as the intake port can be suppressed. Therefore, wetting of the wall surface with fuel can be effectively reduced. As a result, fuel consumption can be improved.

Moreover, (3) In this embodiment, the specific-shaped outer wall surfaces 61 and 62 are formed so that the outline in the cross section by virtual plane VP1 becomes linear (refer FIG. 2 (A)).
Moreover, (4) In this embodiment, the specific-shaped outer wall surfaces 61 and 62 are formed in a curved surface shape (see FIGS. 2A and 2B).
(6) In the present embodiment, a plurality of nozzle holes 13 are formed in the nozzle bottom 12 (see FIGS. 2A and 2B).

Moreover, (7) In this embodiment, the nozzle hole 13 is formed so that the exit-side opening 132 is positioned on the virtual circle VC1 centering on the axis Ax2 (see FIG. 2B). Moreover, the specific-shaped outer wall surfaces 61 and 62 are formed in the radial direction outer side with respect to the nozzle hole 13 (refer FIG. 2 (A), (B)).
(10) In the present embodiment, the nozzle hole 13 is formed such that the central axis CL1 is inclined with respect to the axis Ax2 (see FIG. 2A).
(11) In the present embodiment, the nozzle hole 13 is formed in a tapered shape so that the inner wall moves away from the central axis CL1 as it goes from the inlet-side opening 131 side to the outlet-side opening 132 side (FIG. 2 ( A) and (B)).

  In the present embodiment, the nozzle holes 13 are arranged and formed as described above, and the specific-shaped outer wall surfaces 61 and 62 are arranged and formed. Therefore, when the fuel is injected from the injection hole 13 with an inclination with respect to the axis Ax2, the action of drawing the air around the spray-shaped outer wall surfaces 61 and 62 around the spray in the spray direction due to the pressure change accompanying the injection is greatly increased. can do. Therefore, it is possible to suppress the fuel spray from adhering to the wall surface of the member connected to the engine such as the intake port. Therefore, wetting of the wall surface with fuel can be reduced more effectively.

(Second Embodiment)
A part of the fuel injection device according to the second embodiment of the present invention is shown in FIG. The second embodiment is different from the first embodiment in the shapes of the opening forming inner wall surface 50 and the opening forming outer wall surface 51 of the nozzle bottom 12.

In the second embodiment, the nozzle bottom 12 is formed so as to protrude to the opposite side of the nozzle cylinder 11. Each of the opening forming inner wall surface 50 and the opening forming outer wall surface 51 is formed so that the contour in the cross section by the virtual plane VP1 is curved (see FIG. 3A). That is, the opening formation inner wall surface 50 and the opening formation outer wall surface 51 are formed in a curved surface shape.
The second embodiment is the same as the first embodiment except for the points described above.

As described above, (5) in this embodiment, the opening forming outer wall surface 51 is formed in a curved surface shape.
Also in the second embodiment, when the fuel is injected from the nozzle hole 13, the air in the vicinity of the specific-shaped outer wall surfaces 61 and 62 can be effectively drawn in the fuel spray direction (FIGS. 3A and 3B). )reference). At this time, the air flows smoothly along the curved opening-formed outer wall surface 51 without peeling off at the boundary between the specific-shaped outer wall surface 61 and the opening-formed outer wall surface 51. Thereby, like 1st Embodiment, adhesion of the fuel spray to the wall surface of the member connected to an engine, such as an intake port, can be suppressed. Therefore, wetting of the wall surface with fuel can be effectively reduced.

(Third embodiment)
A part of the fuel injection device according to the third embodiment of the present invention is shown in FIG. The third embodiment differs from the first embodiment in the shapes of the specific-shaped outer wall surfaces 61 and 62 of the nozzle bottom 12.

  Among the specific shape outer wall surface 61 and the specific shape outer wall surface 62, the specific shape outer wall surface 61 whose inner edge end is connected to the outer edge end of the opening forming outer wall surface 51 has a contour in a cross section by the virtual plane VP1 that is “perpendicular to the axis Ax2. It is formed so as to rise toward the nozzle cylinder portion 11 with respect to a virtual orthogonal straight line VA1 passing through the outer edge of the opening forming outer wall surface 51 (see FIGS. 4A and 4B).

  Among the specific shape outer wall surface 61 and the specific shape outer wall surface 62, the specific shape outer wall surface 62 whose inner edge is connected to the outer edge of the other specific shape outer wall surface (61) has an outline in a cross section by the virtual plane VP <b> 1. It is formed so as to rise toward the nozzle cylinder portion 11 with respect to a virtual extension straight line VE1 obtained by extending the outline of the specific-shaped outer wall surface 61 on the inner side in the radial direction outward (see FIGS. 4A and 4B).

  In the third embodiment, the specific-shaped outer wall surfaces 61 and 62 are formed so that the contour in the cross section by the virtual plane VP1 is curved. (See FIG. 4A). The virtual straight line VL2 and the virtual extension straight line VE1 along the specific shape outer wall surface 62 coincide with each other at the inner edge of the specific shape outer wall surface 62. That is, unlike the first embodiment, no edge is formed between the specific shape outer wall surface 61 and the specific shape outer wall surface 62, and the specific shape outer wall surface 61 and the specific shape outer wall surface 62 are smoothly connected. ing.

  An angle θb1 formed between the virtual straight line VL1 along the specific shape outer wall surface 61 and the axis Ax2 at the inner edge of the specific shape outer wall surface 61 is along the specific shape outer wall surface 62 and the virtual extension straight line VE1 at the inner edge end of the specific shape outer wall surface 62. It is smaller than the angle θb2 formed by the virtual straight line VL2 and the axis Ax2. Here, the angle θc1 formed by the virtual straight line VL1 and the central axis CL1 is equal to the difference between θb1 and θa1. Further, the angle θc2 formed by the virtual straight line VL2 and the central axis CL1 is equal to the difference between θb2 and θa1 (see FIG. 4A).

  As described above, (3) in the present embodiment, the specific-shaped outer wall surfaces 61 and 62 are formed so that the contour in the cross section by the virtual plane VP1 is curved (see FIG. 4A). Therefore, when fuel is injected from the nozzle hole 13, air in the vicinity of the specific shape outer wall surfaces 61 and 62 is drawn in the fuel spray direction smoothly along the specific shape outer wall surfaces 61 and 62 (FIG. 4A). (See (B)).

  In the third embodiment, when fuel is injected from the nozzle hole 13, the air in the vicinity of the specific-shaped outer wall surfaces 61 and 62 can be drawn more effectively in the fuel spray direction. Thereby, the adhesion of the fuel spray to the wall surface of the member connected to the engine such as the intake port can be suppressed. Therefore, wetting of the wall surface with fuel can be reduced more effectively.

(Fourth embodiment)
A part of the fuel injection device according to the fourth embodiment of the present invention is shown in FIG. The fourth embodiment differs from the first embodiment in the shape of the nozzle bottom 12.
In the fourth embodiment, the nozzle bottom 12 has a specific shape outer wall surface 63 between the specific shape outer wall surface 61 and the specific shape outer wall surface 62.

  Among the specific shape outer wall surface 61, the specific shape outer wall surface 62, and the specific shape outer wall surface 63, the specific shape outer wall surface 63 whose inner edge is connected to the outer edge of the other specific shape outer wall surface (61) is a cross section taken along the virtual plane VP1. Is formed so as to rise toward the nozzle cylinder portion 11 with respect to the “virtual extension straight line VE1 obtained by extending the contour of the outer wall 61 of the specific shape radially inside” radially (FIG. 5A, ( B)).

  The specific-shaped outer wall surface 63 is formed so that the contour in the cross section by the virtual plane VP1 is linear. Further, the specific-shaped outer wall surfaces 61, 63, 62 are continuously arranged toward the radially outer side of the opening forming outer wall surface 51 between the outer edge of the opening forming outer wall surface 51 and the outer wall surface of the nozzle cylinder portion 11. Concentric circles are formed (see FIGS. 5A and 5B).

  Of the specific shape outer wall surface 61, the specific shape outer wall surface 62, and the specific shape outer wall surface 63, the specific shape outer wall surface 62 whose inner edge is connected to the outer edge of another specific shape outer wall surface (63) is a virtual plane VP1. The contour in the cross section is formed so as to rise toward the nozzle cylinder portion 11 with respect to the “virtual extension straight line VE3 obtained by extending the contour of the outer wall 63 of the specific shape radially inward in the radial direction” (FIG. 5A). (See (B)).

  The angle θb3 formed by the virtual straight line VE3 and the virtual straight line VL3 along the specific shape outer wall surface 63 and the axis Ax2 is smaller than the angle θb2 formed by the virtual straight line VL2 along the specific shape outer wall surface 62 and the axis Ax2, and the specific shape outer wall surface It is larger than the angle θb1 formed by the imaginary straight line VL1 along the axis 61 and the axis Ax2. Here, the angle θc3 formed by the virtual straight line VL3 and the central axis CL1 is equal to the difference between θb3 and θa1 (see FIG. 5A). In the present embodiment, θc1, θc2, and θc3 are set to about 90 degrees.

  As described above, (1) in the fourth embodiment, the nozzle bottom portion 12 is located on the radially outer side of the opening forming outer wall surface 51 between the outer edge of the opening forming outer wall surface 51 and the outer wall surface of the nozzle cylinder portion 11. It has specific-shaped outer wall surfaces 61, 63, 62 formed concentrically so as to line up continuously.

  In the present embodiment, when fuel is injected from the nozzle hole 13, the air in the vicinity of the specific-shaped outer wall surfaces 61, 63, 62 can be particularly effectively drawn in the fuel spray direction (FIGS. 5A and 5B). )reference). Thereby, like 1st Embodiment, adhesion of the fuel spray to the wall surface of the member connected to an engine, such as an intake port, can be suppressed. Therefore, wetting of the wall surface with fuel can be effectively reduced.

(Fifth embodiment)
A part of the fuel injection device according to the fifth embodiment of the present invention is shown in FIG. The fifth embodiment is different from the first embodiment in the configuration of the nozzle bottom 12.

  In the fifth embodiment, the nozzle bottom 12 has a plurality of protrusions 70. The protrusion 70 is formed so as to protrude from the outer wall surfaces 61 and 62 having a specific shape to the side opposite to the nozzle cylinder portion 11. Eight protrusions 70 are formed so as to be arranged at equal intervals in the circumferential direction of the nozzle bottom 12. The protrusion 70 is formed at a position corresponding to the radially outer side of the region between the plurality of nozzle holes 13. The protrusion 70 is formed so that the shape seen from the direction of the axis Ax2 is an arc shape (see FIG. 6B). The end surface of the protrusion 70 opposite to the nozzle cylinder 11 is formed on the same plane as the end surface 122 of the nozzle bottom 12 opposite to the nozzle cylinder 11 (FIGS. 6A and 6B). reference).

The protrusion 70 has guide wall surfaces 71 at both ends in the circumferential direction of the nozzle bottom 12. The guide wall surface 71 is formed in a planar shape along a virtual plane VP2 that is in contact with the outer edge of the opening 132 on the outlet side of the nozzle hole 13. When fuel is injected from the nozzle hole 13, the air on the radially outer side of the nozzle bottom 12 is guided along the guide wall surface 71 to the nozzle hole 13 side. That is, when the fuel is injected from the nozzle hole 13, the guide wall surface 71 can guide the air flow so that the air on the radially outer side of the nozzle bottom 12 is directed to the nozzle hole 13 side (FIG. 6A). (See (B)).
In addition, in this embodiment, the specific-shaped outer wall surfaces 61 and 62 are formed in the radial direction outer side with respect to each nozzle hole 13 (refer FIG. 6 (A), (B)).

  As described above, (8) In the present embodiment, the nozzle bottom 12 causes the air flow so that air radially outside the nozzle bottom 12 is directed toward the nozzle hole 13 when fuel is injected from the nozzle hole 13. A guide wall surface 71 capable of guiding is provided. Therefore, when injecting fuel from the nozzle hole 13, the air in the vicinity of the specific-shaped outer wall surfaces 61 and 62 can be effectively drawn in the fuel spray direction (see FIGS. 6A and 6B).

  (9) In the present embodiment, the guide wall surface 71 is formed along a virtual plane VP2 that is in contact with the outer edge of the opening 132 on the outlet side of the nozzle hole 13. Therefore, the air flow can be effectively guided by the guide wall surface 71 so that the air on the radially outer side of the nozzle bottom 12 is directed toward the nozzle hole 13. Since the guide wall surface 71 is planar, it is easy to process.

(Sixth embodiment)
FIG. 7 shows a part of a fuel injection device according to a sixth embodiment of the present invention. The sixth embodiment is different from the first embodiment in the configuration of the nozzle bottom 12.
In the sixth embodiment, four nozzle holes 13 are formed at equal intervals in the circumferential direction of the nozzle bottom 12 (see FIG. 7B). Further, the nozzle hole 13 is formed so that the opening 132 on the outlet side is positioned on the virtual circle VC1.

The nozzle bottom portion 12 has a specific-shaped outer wall surface 64 that is formed in a concave shape that is recessed toward the nozzle tube portion 11 between the outer edge of the opening forming outer wall surface 51 and the outer wall surface of the nozzle tube portion 11. The specific-shaped outer wall surface 64 can be formed by, for example, cutting a corner portion of the end portion of the cylindrical nozzle portion 10 into a cylindrical surface shape. In other words, in the present embodiment, the specific-shaped outer wall surface 64 coincides with a part of a virtual cylindrical surface arranged so that the axis is inclined with respect to the axis Ax2. That is, the specific shape outer wall surface 64 is formed in a curved surface shape.
Four specific-shaped outer wall surfaces 64 are formed so as to be arranged at equal intervals in the circumferential direction of the nozzle bottom 12. The specific-shaped outer wall surface 64 is formed at a position corresponding to the radially outer side of each of the four nozzle holes 13 (see FIG. 7B).

The specific-shaped outer wall surface 64 rises toward the nozzle cylinder portion 11 with respect to the “virtual orthogonal straight line VA1 orthogonal to the axis Ax2 and passing through the outer edge of the opening-formed outer wall surface 51” in the cross section of the virtual plane VP1 including the axis Ax2. (See FIGS. 7A and 7B).
In the present embodiment, the specific-shaped outer wall surface 64 is formed so that the contour in the cross section of the virtual plane VP1 is linear (see FIG. 7A).

An angle θb4 formed by the virtual straight line VL4 along the specific shape outer wall surface 64 and the axis Ax2 is larger than θa1. Here, the angle θc4 formed by the virtual straight line VL4 and the central axis CL1 is equal to the difference between θb4 and θa1 (see FIG. 7A). In the present embodiment, θc4 is set to about 90 degrees.
Further, the angle θd4 formed by the virtual orthogonal straight line VA1 and the virtual straight line VL4, that is, the rising angle of the specific-shaped outer wall surface 64 with respect to the virtual orthogonal straight line VA1 is equal to the angle obtained by subtracting 90 degrees from θb4.

  As described above, (1) in the present embodiment, the nozzle bottom portion 12 is formed in a concave shape that is recessed toward the nozzle tube portion 11 between the outer edge of the opening forming outer wall surface 51 and the outer wall surface of the nozzle tube portion 11. The specific shape outer wall surface 64 is provided.

  The specific-shaped outer wall surface 64 has a contour in a cross section by a virtual plane VP1 including the axis Ax2 of the nozzle cylinder portion 11 with respect to “virtual orthogonal straight line VA1 orthogonal to the axis Ax2 and passing through the outer edge of the opening-forming outer wall surface 51”. It is formed so as to rise to the nozzle tube portion 11 side.

  In the present embodiment, a concave specific-shaped outer wall surface 64 that is recessed toward the nozzle tube portion 11 is formed on the radially outer side of the opening-forming outer wall surface 51 in which the opening 132 on the outlet side of the nozzle hole 13 is formed. Therefore, when fuel is injected from the nozzle hole 13, the air in the vicinity of the specific shape outer wall surface 64 can be effectively drawn in the fuel spray direction. Thereby, it is possible to suppress the adhesion of fuel spray to the wall surface of a member connected to the internal combustion engine such as an intake port or a member constituting the internal combustion engine such as a cylinder or a piston. Therefore, wetting of the wall surface with fuel can be effectively reduced. As a result, fuel consumption can be improved.

Moreover, (3) In this embodiment, the specific-shaped outer wall surface 64 is formed so that the outline in the cross section by the virtual plane VP1 is linear (see FIG. 7A).
Moreover, (4) In this embodiment, the specific-shaped outer wall surface 64 is formed in a curved surface shape (see FIGS. 7A and 7B).

  Further, (7) in the present embodiment, the nozzle hole 13 is formed such that the outlet-side opening 132 is located on the virtual circle VC1 centered on the axis Ax2. Moreover, the specific-shaped outer wall surface 64 is formed on the radially outer side with respect to the nozzle hole 13 (see FIG. 7B).

  In the present embodiment, the nozzle holes 13 are arranged and formed as described above, and the specific-shaped outer wall surface 64 is arranged and formed. Therefore, when the fuel is injected from the injection hole 13 with an inclination with respect to the axis Ax2, the action of drawing the air around the spray, particularly around the outer wall 64 of the specific shape, in the spray direction is increased by the pressure change accompanying the injection. Can do. Therefore, it is possible to suppress the fuel spray from adhering to the wall surface of the member connected to the engine such as the intake port. Therefore, wetting of the wall surface with fuel can be reduced more effectively.

(Seventh embodiment)
FIG. 8 shows a part of a fuel injection device according to a seventh embodiment of the present invention. The seventh embodiment differs from the sixth embodiment in the shape of the specific-shaped outer wall surface 64 of the nozzle bottom 12.

In the seventh embodiment, the specific-shaped outer wall surface 64 is formed in a planar shape between the outer edge of the opening-forming outer wall surface 51 and the outer wall surface of the nozzle cylinder portion 11. The specific-shaped outer wall surface 64 can be formed, for example, by chamfering a corner portion of the end portion of the cylindrical nozzle portion 10 in a planar shape in a part of the circumferential direction. That is, in this embodiment, the specific-shaped outer wall surface 64 coincides with a part of an imaginary plane arranged so as to be inclined with respect to the axis Ax2.
In the present embodiment, the specific-shaped outer wall surface 64 is formed so that the contour in the cross section by the virtual plane VP1 is linear (see FIG. 8A).
The configuration of the seventh embodiment is the same as that of the sixth embodiment except for the points described above.

  Also in the seventh embodiment, when fuel is injected from the nozzle hole 13, the air in the vicinity of the specific-shaped outer wall surface 64 can be effectively drawn in the fuel spray direction (see FIGS. 8A and 8B). ). Thereby, like 6th Embodiment, adhesion of fuel spray to the wall surface of the member connected to an engine, such as an intake port, can be suppressed. Therefore, wetting of the wall surface with fuel can be effectively reduced.

(Eighth embodiment)
FIG. 9 shows a part of a fuel injection device according to an eighth embodiment of the present invention. The eighth embodiment differs from the sixth embodiment in the number of specific-shaped outer wall surfaces 64 of the nozzle bottom 12 and the like.
In the eighth embodiment, six nozzle holes 13 are formed at equal intervals in the circumferential direction of the nozzle bottom 12 (see FIG. 9B). Further, the nozzle hole 13 is formed so that the opening 132 on the outlet side is positioned on the virtual circle VC1.

Six specific-shaped outer wall surfaces 64 are formed so as to be arranged at equal intervals in the circumferential direction of the nozzle bottom 12. The specific-shaped outer wall surface 64 is formed at a position corresponding to the radially outer side of each of the six nozzle holes 13 (see FIG. 9B).
The configuration of the eighth embodiment is the same as that of the sixth embodiment except for the points described above.

  Also in the eighth embodiment, when fuel is injected from the nozzle hole 13, the air in the vicinity of the specific-shaped outer wall surface 64 can be effectively drawn in the fuel spray direction (see FIGS. 9A and 9B). ). Thereby, like 6th Embodiment, adhesion of fuel spray to the wall surface of the member connected to an engine, such as an intake port, can be suppressed. Therefore, wetting of the wall surface with fuel can be effectively reduced.

(Other embodiments)
In the first embodiment described above, the nozzle bottom has two specific-shaped outer wall surfaces (61, 62) that are concentric, and in the fourth embodiment, three specific-shaped outer wall surfaces (61, 62, 63). In contrast, in another embodiment of the present invention, the nozzle bottom may have four or more specific-shaped outer wall surfaces that are concentric.

  Moreover, in other embodiment of this invention, how many nozzle holes may be formed in the nozzle bottom part. A single nozzle hole may be formed at the nozzle bottom. The nozzle hole may not be formed on a virtual circle centered on the axis of the nozzle cylinder.

  Moreover, in other embodiment of this invention, if there is no obstruction | occlusion requirement on a structure, you may combine the above-mentioned embodiment how. For example, the seventh embodiment may be combined with the fifth embodiment, and the guide wall surface shown in the fifth embodiment may be provided on the nozzle bottom portion shown in the seventh embodiment.

  Moreover, in the above-mentioned embodiment, the example in which the central axis of the nozzle hole is formed so as to be inclined with respect to the axis of the nozzle cylinder portion has been shown. On the other hand, in another embodiment of the present invention, the nozzle hole may be formed such that the central axis is parallel or twisted with respect to the axis of the nozzle cylinder.

  Further, in the above-described embodiment, an example in which the nozzle hole is formed in a tapered shape so that the inner wall is separated from the central axis as it goes from the inlet side opening side to the outlet side opening side is shown. On the other hand, in another embodiment of the present invention, the nozzle hole may be formed in a straight shape so that the inner diameter is constant from the opening side on the inlet side to the opening side on the outlet side. The nozzle hole may be formed in a tapered shape so that the inner wall approaches the central axis from the opening side on the inlet side toward the opening side on the outlet side.

Moreover, in the above-mentioned embodiment, the example which applies a fuel-injection apparatus to a port-injection type gasoline engine was shown. In contrast, in another embodiment of the present invention, the fuel injection device may be applied to, for example, a direct injection gasoline engine, a diesel engine, or the like. In this case, the fuel injection device of the present invention can prevent the fuel spray from adhering to the wall surfaces of the members constituting the internal combustion engine such as the cylinder and the piston. Therefore, wetting of the wall surface with fuel can be effectively reduced. Therefore, fuel efficiency can be improved even in a direct injection engine.
Thus, the present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the gist thereof.

DESCRIPTION OF SYMBOLS 1 Fuel injection apparatus, 10 Nozzle part, 11 Nozzle cylinder part, 12 Nozzle bottom part, 13 Injection hole, 14 Valve seat, 30 Needle, 51 Opening formation outer wall surface, 61, 62, 63, 64 Specific shape outer wall surface, 100 Fuel passage , Ax2 axis, VP1 virtual plane, VA1 virtual orthogonal straight line, VE1, VE3 virtual extension straight line

Claims (11)

A nozzle cylinder portion (11) having a fuel passage (100) on the inner side, a nozzle bottom portion (12) closing one end of the nozzle cylinder portion, an end surface (121) of the nozzle bottom portion on the nozzle cylinder portion side, and the nozzle cylinder portion; Is formed in an annular shape around the nozzle hole on the nozzle cylinder side of the nozzle bottom, connecting the end face (122) on the opposite side and injecting fuel in the fuel passage. A nozzle part (10) having a valve seat (14);
One end can be contacted with the valve seat and can be moved back and forth in the axial direction. A needle (30) for
The nozzle bottom portion is formed at a position through which the axis (Ax2) of the nozzle cylinder portion passes, and an opening forming outer wall surface (51) in which an opening (132) on the outlet side of the nozzle hole is formed, and the opening forming outside A plurality of specific-shaped outer wall surfaces (61, 62, 63) concentrically formed so as to be continuously arranged toward the radially outer side of the opening-forming outer wall surface between the outer edge of the wall surface and the outer wall surface of the nozzle cylinder portion. )
Among the plurality of specific shape outer wall surfaces, the specific shape outer wall surface (61) in which an inner edge end is connected to an outer edge end of the opening forming outer wall surface has a contour in a cross section by a virtual plane (VP1) including the axis. Formed so as to rise to the nozzle tube side with respect to a virtual orthogonal straight line (VA1) perpendicular to the axis and passing through an outer edge of the opening-forming outer wall surface,
Among the plurality of specific shape outer wall surfaces, the specific shape outer wall surfaces (62, 63) whose inner edge ends connect to the outer edge ends of the other specific shape outer wall surfaces (61, 63) are contours in a cross section of the virtual plane. Is a fuel injection device (1) formed so as to rise toward the nozzle cylinder side with respect to a "virtual extension straight line (VE1, VE3) obtained by extending the contour of the outer wall surface of the specific shape radially inward in the radial direction" . A nozzle cylinder portion (11) having a fuel passage (100) on the inner side, a nozzle bottom portion (12) closing one end of the nozzle cylinder portion, an end surface (121) of the nozzle bottom portion on the nozzle cylinder portion side, and the nozzle cylinder portion; Is formed in an annular shape around the nozzle hole on the nozzle cylinder side of the nozzle bottom, connecting the end face (122) on the opposite side and injecting fuel in the fuel passage. A nozzle part (10) having a valve seat (14);
One end can be contacted with the valve seat and can be moved back and forth in the axial direction. A needle (30) for
The nozzle bottom portion is formed at a position through which the axis (Ax2) of the nozzle cylinder portion passes, and an opening forming outer wall surface (51) in which an opening (132) on the outlet side of the nozzle hole is formed, and the opening forming outside A specific shape outer wall surface (64) formed in a concave shape or a flat shape recessed toward the nozzle tube portion between the outer edge of the wall surface and the outer wall surface of the nozzle tube portion;
The specific shape outer wall surface has the contour in a cross section of a virtual plane (VP1) including the axis line with respect to the "virtual orthogonal straight line (VA1) orthogonal to the axis line and passing through the outer edge of the opening forming outer wall surface". A fuel injection device formed so as to stand up to the section side.   The fuel injection device according to claim 1 or 2, wherein the specific shape outer wall surface is formed such that a contour in a cross section by the virtual plane is linear or curved.   The fuel injection device according to any one of claims 1 to 3, wherein the specific-shaped outer wall surface is formed in a curved surface shape or a planar shape.   The fuel injection device according to any one of claims 1 to 4, wherein the opening forming outer wall surface is formed in a curved surface shape.   The fuel injection device according to any one of claims 1 to 5, wherein a plurality of the nozzle holes are formed in the nozzle bottom portion. The nozzle hole is formed such that the opening (132) on the outlet side is located on a virtual circle (VC1) centered on the axis,
The fuel injection device according to any one of claims 1 to 6, wherein the specific-shaped outer wall surface is formed radially outward with respect to the nozzle hole.   The said nozzle bottom part has a guide wall surface (71) which can guide the flow of air so that the air of the radial direction outer side of the said nozzle bottom part may go to the said nozzle hole side when fuel is injected from the said nozzle hole. The fuel injection device according to any one of claims 7 to 9.   The fuel injection device according to claim 8, wherein the guide wall surface is formed along the virtual plane (VP2) in contact with an outer edge of the opening (132) on the outlet side of the nozzle hole.   The fuel injection device according to any one of claims 1 to 9, wherein the injection hole is formed such that a central axis (CL1) is inclined with respect to the axis.   The said nozzle hole is formed in the taper shape so that an inner wall may leave | separate from a center axis | shaft (CL1) as it goes to the opening (132) side of an exit side from the opening (131) side of an entrance side. The fuel injection device according to one item.

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