JP5785892B2 - Fuel injection valve - Google Patents

Description

  The present invention relates to a structure of a fuel injection valve of an internal combustion engine, and more particularly to a fuel pipe of a fuel injection valve body.

  The fuel injection valve mounted on the internal combustion engine has a different mounting position on the internal combustion engine depending on the injection mode for injecting fuel, and the mounting position on the internal combustion engine depends on the mode for injection into the intake port and the mode for direct injection into the cylinder. Different. Especially in the form of directly injecting fuel into the cylinder, the tip of the fuel injection valve needs to face the inside of the cylinder, and the side injection system is mounted from the part located under the intake port into the cylinder. And the center injection system mounted on the top of the cylinder.

  The side injection method is generally a method in which fuel is injected from the lower part of the intake valve into the combustion chamber, and in order to inject the fuel uniformly into the combustion chamber, the air flow and spray penetration force are controlled to control the combustion chamber. The fuel mixing ratio is adjusted. In the case of the side injection method, a fuel pipe through which high-pressure fuel is pumped can be disposed near the mounting position of the fuel injection valve, and the fuel injection valve is connected to a receiving portion of the fuel pipe via an O-ring. be able to.

  In the center injection system, the fuel can be injected into the combustion chamber from the vicinity of the center of the cylinder head provided at the top of the cylinder, so that the fuel can be uniformly diffused and mixed in the cylinder. The cylinder head is provided with an intake valve, an exhaust valve, a spark plug, and the like. For this reason, in the center injection method, it is necessary to avoid the positions of the intake valve, the exhaust valve, and the spark plug. Further, it is necessary to mount a fuel injection valve so as to avoid a camshaft for driving the intake valve and the exhaust valve. Therefore, in the center injection method, the distance from the fuel injection valve to the fuel pipe is longer than in the side injection method, and the length of the fuel injection valve structure, in particular, the length between the fuel injection valve drive unit and the fuel supply port is increased. There is a need to. For example, in the fuel injection valve disclosed in Japanese Patent Application Laid-Open No. 2009-167843, the fuel supply pipe between the drive unit and the fuel inlet is lengthened.

  In the fuel injection valve disclosed in Japanese Patent Application Laid-Open No. 2009-167743, the fuel supply pipe constitutes a part of the fuel injection valve main body. By making the fuel injection valve main body longer, the drive unit and the fuel inlet The length between is long.

JP 2009-167743 A

  In order to dispose the fuel injection valve in the cylinder head, it is necessary to make the length between the drive unit and the fuel inlet longer than that in the side injection type. It is necessary to change the structure of the fuel injection valve body with the center injection method.

  In addition, due to the length of the fuel injection valve body, there is a decrease in reliability related to the connection between the fuel injection valve and the fuel pipe, and the influence of external force applied to the fuel injection valve body due to vibration generated by driving the engine. The problem of becoming larger arises. In particular, when a lateral force or bending occurs, the force applied to the fuel injection valve body is increased, so that it is necessary to reduce the force applied to the fuel injection valve body.

  The fuel supplied to the fuel injection valve is pressurized by a high-pressure fuel pump. For this reason, the means for solving the above-mentioned problems must be guaranteed for the high-pressure fuel pressurized by the high-pressure fuel pump.

  It is an object of the present invention that there is no need to greatly change the structure of the fuel injection valve body between the side injection method and the center injection method, and it has high reliability even if the length between the drive unit and the fuel inlet is increased. It is to provide a fuel injection valve.

In order to solve the above-mentioned object, in the fuel injection valve of the present invention, a fuel injection valve main body including a drive portion and having a fuel passage formed therein, and a connector for connecting wiring for supplying current to the drive portion; The first fuel passage member connected to the fuel passage, the first fuel passage member connected to the fuel passage, and disposed closer to the fuel inlet than the first fuel passage member. A second fuel passage member; a third fuel passage member connected to the second fuel passage member and disposed closer to the fuel inlet than the second fuel passage member; and the second fuel passage member A deformation promoting portion having a bending strength weaker than a bending strength of a connection portion between fuel passage members and a bending strength of a connection portion between the first fuel passage member and the fuel injection valve body, and the connector is axially In the second fuel passage portion While it is disposed in the fuel inlet side than are those located in positions corresponding to the third fuel passage member.

The deformation promoting part may be constituted by a thin part formed in an annular shape on the outer peripheral surface of the second fuel passage member .

  A relief portion may be provided at a connection portion between the first fuel passage member and the fuel injection valve main body.

A relief portion may be provided when the fuel injection valve body is abutted against the first fuel passage member.

  The deformation promoting portion may be provided in the third fuel passage member.

The driving unit is constituted by a solenoid, the wiring for energizing the solenoid before Symbol first, provided along the composed fuel passage portion by the second and third fuel passage member, the first It is good to be comprised from the some member divided corresponding to the 2nd and 3rd fuel passage member.

  The first fuel passage member may be welded and joined to the fuel injection valve main body, and a portion serving as a welded joint with the fuel injection valve main body may be an annular thin portion.

  According to the present invention, even when an external force such as bending or lateral force is applied to the fuel injection valve main body, a load is not applied to the valve body itself for injecting fuel, and a highly reliable fuel injection valve can be provided. . Further, the structure for the center injection system can be obtained by simply adding a member for extending the fuel passage to the conventional side injection system fuel injection valve.

It is a longitudinal cross-sectional view of the fuel injection valve which concerns on this invention. It is a longitudinal cross-sectional view which shows the fuel channel part couple | bonded with the fuel injection valve main body. It is a figure which shows the other example which connects a fuel injection valve to a fuel piping receiving part.

  Embodiments of a fuel injection valve according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this Example.

  The fuel injection valve applied to the present embodiment will be described based on the block diagram of the fuel injection valve in FIG.

  1 is a fuel injection valve main body including a drive unit, 2 is a valve main body, 3 is a nozzle holder, 4 is a core, and 5 is a housing. Fuel pressurized by a high-pressure fuel pump (not shown) is pumped to a fuel injection valve through a fuel pipe (not shown). The fuel pipe is provided with a receiving portion (not shown) for connecting the fuel injection valve, and the fuel inlet 13 of the fuel injection valve is connected to the receiving portion. The fuel supplied from the fuel inlet 13 is sent through the fuel passage 6 to a plurality of fuel injection holes 7 provided at the tip of the fuel injection valve. An anchor 9 is provided at one end of the needle valve 8 and is housed in the nozzle holder 3 so as to reciprocate in the direction along the central axis 15 by the magnetic attractive force acting on the anchor 9 and the biasing force of the spring 10. Has been.

  The spring 10 is disposed between the needle valve 8 and the adjuster pin 11, and the position of the upper end portion of the spring 10 is restrained by the adjuster pin 11. When the spring 10 presses the needle valve 8 against the seat portion 16, the fuel injection hole 7 is closed (more precisely, the fuel passage to the fuel injection hole 7 is closed). The solenoid 12 is arranged on the outer peripheral side of the anchor 9 and the core 4 and on the inner peripheral side of the housing 5 so as to be surrounded by a magnetic circuit constituted by the anchor 9, the core 4, and a yoke constituted by the housing 5. ing. A drive current from a drive circuit (not shown) is passed through the solenoid 12 and excited to generate a magnetic attractive force, and the anchor 9 is pulled up toward the core 4 in the axial direction (direction along the central axis 15). Accordingly, the needle valve 8 is pulled up in the axial direction by the anchor 9, the needle valve 8 is separated from the seat portion 16, the plurality of fuel injection holes 7 are opened, and fuel is injected.

  Next, description will be made with reference to the longitudinal sectional view shown in FIG.

  The fuel passage portion 201 coupled to the fuel injection valve body 1 is constituted by tubular fuel passage members 202, 203, and 204, and constitutes a fuel passage that is connected to the fuel injection valve body 1 and extended. Here, the fuel injection valve body 1 is a portion from an end portion (upper end portion) to which the fuel passage member 202 is connected to a tip end portion (lower end portion) in which the fuel injection hole 7 is provided, and includes a drive unit. The fuel injection valve can be used in the side injection method. Since the fuel injection valve main body 1 is also a part including a drive unit, it may be called a fuel injection valve drive unit.

  Each fuel passage member 202, 203, 204 is connected by welding or the like. The fuel passage member 203 is a member for adjusting the entire length of the fuel passage portion 201. The fuel passage member 202 is a member for connecting the fuel injection valve main body 1 and the fuel passage member 203. The fuel passage member 204 is a member for connecting to a receiving portion of a fuel pipe (not shown), and is connected to the fuel passage member 203. An O-ring 14 for sealing is provided at the end of the fuel passage member 204 on the side connected to the receiving portion of the fuel pipe.

  First, the fuel passage member 202 will be described. The diameter of the fuel passage member 202 connected to the fuel injection valve body 1 is formed larger than the diameter of the side connected to the fuel passage member 203. The large diameter side of the fuel passage member 202 is fitted to the end portion of the fuel injection valve main body 1, and a portion 202a is connected to the fuel injection main body 1 by, for example, welding or the like. 202a is an annular thin-walled portion, and is formed in an annular shape on the outer peripheral surface of the end connected to the fuel injection valve body 1 so that the wall thickness is thinner than that on the downstream and upstream sides for welding. Has been. In addition to the outer peripheral surface of the fuel passage member 202 at the joint portion between the fuel passage member 202 and the fuel injection valve body 1, the outer peripheral surface of the fuel passage member 202 at the joint portion between the fuel passage members 202 and 203, the fuel passage member 204. A thin wall portion formed in an annular shape in the circumferential direction is provided on the outer peripheral surface of the fuel passage member 204 at the joint portion between and.

  A projecting portion 202b protruding toward the center side is provided in an annular shape on the inner peripheral surface of the fuel passage member 202, and the fuel injection member main body 1 and the fuel injection valve main body 1 are connected to each other by abutting 202b against the end surface of the fuel injection valve main body 1. Specifies the coupling position.

  Furthermore, in order to abut the fuel injection valve main body 1 against the portion 202b, a space 202c constituting an escape portion is provided.

  Next, the fuel passage member 203 will be described. The fuel passage member 203 is a member for adjusting the overall length of the fuel passage portion 201 and adjusting the total length of the fuel passage portion 201 to the distance between the fuel injection valve body 1 and the fuel pipe. For example, when the fuel injection valve is disposed at the center of the cylinder head, it is necessary to connect the fuel injection valve and the fuel pipe through the camshaft. For this purpose, the fuel passage on the fuel injection valve main body 1 side needs to be extended, but the length for connecting the fuel injection valve and the fuel pipe is adjusted by the fuel passage member 203.

  Next, the deformation promoting portion 203a provided in the fuel passage member 203 will be described. A lateral force is applied to the fuel injection valve main body 1 when connecting the fuel passage portion 201 constituted by the fuel passage members 202, 203, and 204 to the fuel pipe. Further, in a state where the fuel passage portion 201 is connected to the fuel pipe, a bending force is generated in the fuel injection valve main body 1 and the fuel passage portion 201 by the vibration of the engine while the engine is driven. By providing the fuel passage portion 201 with a portion (deformation promoting portion 203a) that is weaker than the fuel injection valve main body 1 side, external force can be suppressed from being applied to the fuel injection valve main body 1. Further, the deformation promoting portion 203a includes a connecting portion (joining portion) between the fuel injection valve body 1 and the fuel passage member 202, a connecting portion (joining portion) between the fuel passage member 202 and the fuel passage member 203, and the fuel passage member 203 and the fuel. By making it easier to deform than the connecting portion (joining portion) with the passage member 204 (lowering rigidity and weakening bending strength), each connecting portion (joining portion) becomes difficult to break, and reliability can be improved. . In this embodiment, the deformation promoting portion 203a is configured as a thin portion formed in an annular shape on the outer peripheral surface of the fuel passage member 203. The deformation promoting portion 203 a is preferably provided in the fuel passage member 203 rather than the fuel passage member 202 and the fuel passage member 204. The fuel passage member 202 and the fuel passage member 204 have complicated shapes for connection to the fuel pipe and the fuel injection valve main body 1, and it is necessary to increase the strength. The fuel passage member 203 is a member that simply connects the fuel passage member 202 and the fuel passage member 204, and is convenient for forming the deformation promoting portion 203a.

  Next, the fuel passage member 204 will be described. The fuel passage member 204 is a member for connecting the fuel injection valve to the fuel pipe, and the shape shown in FIGS. 1 and 2 is a structure coupled by a fuel sealing method using the O-ring 14. Depending on the fuel sealing method and the properties of the fuel, a flare type joint shape such as the joint shape 301 with the fuel pipe shown in FIG. 3 may be used.

  Next, the wiring 205 that supplies a drive current for driving the fuel injector main body 1 will be described. The wiring 205 is connected to a drive circuit (not shown) via a terminal 205a of the connector 17, and energizes the solenoid 12 with a current supplied from the drive circuit. The wiring 205 may be divided into a plurality of members similarly to the configuration of the fuel pipe. At that time, like the fuel passage portion 201, the wiring member connected to the wiring portion on the fuel injection valve body 1 side, the wiring member for adjusting the overall length of the wiring 205, and the connector 17 connected to the wiring from the drive circuit A wiring member including the terminal 205a may be used. In this case, the wiring 205 is composed of a plurality of wiring members that are divided corresponding to the first fuel passage member 202, the second fuel passage member 203, and the third fuel passage member 204.

  The outer periphery of the first fuel passage member 202, the second fuel passage member 203, and the third fuel passage member 204 is molded with the resin 18 so as to fill the wiring 205 together with the fuel passage members 202 to 204. .

DESCRIPTION OF SYMBOLS 1 Fuel injection valve main body 2 Valve main body 3 Nozzle holder 4 Core 5 Housing 7 Fuel injection hole 8 Needle valve 9 Anchor 10 Spring 11 Adjuster pin 12 Solenoid 13 Fuel inlet 14 O-ring 15 Center axis 16 Seat part 17 Connector 201 Fuel passage part 202 , 203, 204 Fuel passage member 202a Annular thin portion 202b Protruding portion 202c Space 203a forming escape portion Deformation promoting portion 205 Wiring 205a Terminal 301 Joint shape

Claims (7)

A fuel injection valve body including a drive portion and having a fuel passage formed therein;
A fuel injection valve having a connector for connecting a wiring for supplying current to the drive unit;
A first fuel passage member connected to the fuel passage;
A second fuel passage member connected to the first fuel passage member and disposed closer to the fuel inlet than the first fuel passage member;
A third fuel passage member connected to the second fuel passage member and disposed closer to the fuel inlet than the second fuel passage member;
A deformation promoting portion having a bending strength weaker than a bending strength of a connection portion between fuel passage members and a bending strength of a connection portion between the first fuel passage member and the fuel injection valve body in the second fuel passage member. Provided,
The fuel injection valve according to claim 1, wherein the connector is disposed closer to the fuel inlet side than the second fuel passage member in the axial direction, and is disposed at a position corresponding to the third fuel passage member. The fuel injection valve according to claim 1, wherein
The fuel injection valve according to claim 1, wherein the deformation promoting portion is constituted by a thin portion formed in an annular shape on an outer peripheral surface of the second fuel passage member. The fuel injection valve according to claim 1, wherein
A fuel injection valve characterized in that a relief portion is provided when the fuel injection valve main body abuts against the first fuel passage member. The fuel injection valve according to claim 1, wherein
The fuel injection valve, wherein the second fuel passage member is configured as a member that changes a total length of the fuel passage portion. The fuel injection valve according to claim 1, wherein
A fuel injection valve characterized by being a center injection system mounted on the top of the cylinder. The fuel injection valve according to claim 1, wherein
The drive unit is constituted by a solenoid,
The wiring for energizing the solenoid before Symbol first, provided along the composed fuel passage portion by the second and third fuel passage member, the first, second and third fuel passage A fuel injection valve comprising a plurality of members divided corresponding to the members. The fuel injection valve according to claim 1, wherein
The fuel injection valve according to claim 1, wherein the first fuel passage member is welded and joined to the fuel injection valve main body, and a portion serving as a weld joint with the fuel injection valve main body is an annular thin portion.