JP2013100740A - Support structure of fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a support structure of a fuel injection valve that can inspect whether any O-ring might be left unmounted or any damage of the O-ring might be present, being caused by force feed of air to a fuel supply cap, and can prevent ingress of cleaning water, dust or the like in the fuel supply cap.SOLUTION: In the support structure of the fuel injection valve, a fuel injection part 5 is fitted to a fitting hole 2 of an engine, a fuel supply cap is fitted to an outer circumference of a fuel inlet cylindrical part 6, an O-ring 8 is tightly attached to an inner peripheral surface of the fuel supply cap 20, and a cushion ring 17 is pressed against the fitting hole 2 side at a front end face of the fuel supply cap 20 to support a fuel injection valve I. A one-direction seal part 31 can performing the pressure shift only in one direction from the inner side of the fuel supply cap 20 to the outer side of the cushion ring 17 is formed at least on one part of the cushion ring 17.

Description

  The present invention relates to a support structure for a fuel injection valve having a fuel injection portion at a front end, a fuel inlet tube portion at a rear end, and a rearward annular shoulder portion at an intermediate portion, and in particular, an O-ring is mounted on the outer periphery of the fuel inlet tube portion. A cushion ring that fits around the outer periphery of the fuel inlet cylinder is disposed in contact with the annular shoulder, and the fuel injection part is fitted into the mounting hole of the engine, and the outer periphery of the fuel inlet cylinder is A fuel supply cap is fitted, and the O-ring is brought into close contact with the inner peripheral surface of the fuel supply cap, and the fuel injection valve is supported by pressing the cushion ring toward the mounting hole on the front end surface of the fuel supply cap. The present invention relates to an improvement in the support structure of the fuel injection valve.

  Such a fuel injection valve support structure is known, for example, as disclosed in Patent Document 1 below.

Japanese Utility Model Publication Sho 55-26530

  Conventionally, in such a fuel injection valve support structure, after assembling, in order to forget to attach the O-ring to the fuel inlet cylinder and to check whether the O-ring is damaged, A vent groove is provided on the abutment surface, and after assembly, when air is pumped to the fuel supply cap, it is checked whether there is any air outflow from the vent groove. It is determined that the O-ring has been forgotten or damaged, and reassembly is performed.

  However, in such a support structure of the fuel injection valve, there is a possibility that cleaning water, dust or the like passes through the ventilation groove and adheres to the O-ring in a use state, thereby fouling it.

  The present invention has been made in view of such circumstances. Forgetting to install the O-ring by assembling the O-ring by pumping air to the fuel supply cap after assembly without providing the vent groove as described above. An object of the present invention is to provide a support structure for the fuel injection valve that enables inspection of damage and prevents intrusion of cleaning water, dust, or the like into the fuel supply cap.

  In order to achieve the above object, the present invention provides a support structure for a fuel injection valve having a fuel injection portion at a front end, a fuel inlet tube portion at a rear end, and a rearward annular shoulder portion at an intermediate portion. An O-ring is attached to the outer periphery of the part, a cushion ring that fits to the outer periphery of the fuel inlet tube part is abutted on the annular shoulder, and the fuel injection part is fitted into the mounting hole of the engine. A fuel supply cap is fitted on the outer periphery of the fuel inlet cylinder, the O-ring is brought into close contact with the inner peripheral surface of the fuel supply cap, and the cushion ring is placed on the mounting hole side on the front end surface of the fuel supply cap. In the structure that supports the fuel injection valve by pressing, at least a part of the cushion ring can be moved in one direction of pressure from the inside of the fuel supply cap to the outside of the cushion ring. The first, characterized in that the formation of the direction seal part. In addition, the said annular shoulder part respond | corresponds to the back shoulder part 16 in embodiment of this invention mentioned later.

  According to the present invention, in addition to the first feature, the cushion ring includes a cushion portion that forms a superior arc shape and supports a clamping force between the annular shoulder portion and the fuel supply cap, and an inferior arc shape that forms the cushion ring. A second feature is that the one-way seal portion integrally connects the two peripheral ends of the portion.

  In addition to the second feature of the present invention, the one-way seal portion is fitted to the outer periphery of the fuel inlet tube portion together with the cushion portion, and is in contact with the annular shoulder portion, and the seal base portion A seal lip that protrudes from the rear end of the fuel supply cap so as to expand toward the rear and is in close contact with the front end surface of the fuel supply cap, and the seal lip bends outward with the seal base as a fulcrum. A third feature is that the pressure in the supply cap is released to the outside.

  Furthermore, the present invention is characterized in that, in addition to the second or third feature, positioning means for restricting the position of the one-way seal portion in the fuel injection valve to be constant is provided between the fuel injection valve and the cushion ring. The fourth feature.

  Furthermore, in addition to the fourth feature of the present invention, the annular shoulder portion is formed at an intermediate portion of the fuel injection valve and covered with a synthetic resin coating layer and has a diameter larger than that of the fuel inlet tube portion. Consists of a rear end of the coil portion, and the annular shoulder portion is arranged in a first semicircular shoulder portion and a second semicircular shoulder portion that is arranged so as to be axially displaced with respect to the first semicircular shoulder portion. And a standing wall that rises so as to connect between the first and second semicircular shoulders, and the front end surface of the cushion ring is respectively connected to the first and second semicircular shoulders. The first and second semicircular end surfaces that contact each other and a stopper surface that stands up so as to connect the semicircular end surfaces are in contact with each other so as to prevent relative rotation of the fuel injection valve and the cushion ring. According to a fifth aspect of the present invention, the positioning means is configured by the upright wall and the stopper surface.

  According to the first aspect of the present invention, a unidirectional seal portion that enables pressure movement in only one direction from the inside of the fuel supply cap to the outside of the cushion ring is formed on at least a part of the cushion ring. After the assembly of the fuel injection valve support structure, when inspecting by air pressure feeding to the fuel supply cap, depending on the presence or absence of air outflow from the one-way seal part, forgetting to attach the O-ring to the fuel inlet cylinder or its O-ring The presence or absence of damage can be detected. In addition, even when cleaning water or dust is blown from the outside to the one-way seal part during use, the one-way seal part maintains a closed state in close contact with the front end surface of the fuel supply cap. Intrusion of dust or the like into the fuel supply cap can be prevented.

  According to the second feature of the present invention, the seal lip is provided with flexibility suitable for the one-way valve function, and the cushion portion is provided with rigidity suitable for elastic support of the fuel injection valve. Thus, the cushion ring can exhibit a stable elastic support function for the fuel injection valve while having a one-way seal portion.

  According to the third feature of the present invention, the seal lip of the one-way seal portion can be provided with a good one-way valve function, and the seal base portion is fitted to the outer periphery of the fuel inlet cylinder portion together with the cushion portion. By combining, it is possible to prevent displacement of the cushion ring.

  According to the fourth aspect of the present invention, the positioning means for restricting the position of the one-way seal portion in the fuel injection valve to be constant is provided between the fuel injection valve and the cushion ring, so that the position of the one-way seal portion is For example, with reference to a coupler protruding from one side of the coil section, and during the inspection, it is possible to confirm the outflow of air from the one-way seal section. And work efficiency can be improved.

  According to the fifth aspect of the present invention, the standing wall and the stopper surface constituting the positioning means can be obtained together with the molding of the coating layer of the coil portion and the cushion ring, and there is no need to provide a special positioning means. Cost increase can be suppressed.

1 is a longitudinal side view showing a state in which a fuel injection valve is attached to an engine by a support structure of the present invention. FIG. 2 is a view taken in the direction of arrow 2 in FIG. 1. The disassembled perspective view of the principal part of a fuel injection valve and a cushion ring. (A) is an AA line cross-sectional enlarged view of FIG. 2 which shows a one-way seal part, (B) and (C) are the modifications.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In the present invention, the fuel injection portion side of the electromagnetic fuel injection valve is referred to as the front, and the fuel inlet cylinder portion side is referred to as the rear.

  In FIG. 1, a mounting hole 2 is provided in one side wall of an intake pipe 1 (including a throttle body) of the engine, and an outer end opening of the mounting hole 2 is formed in an annular recess 2a.

  On the other hand, an electromagnetic fuel injection valve (hereinafter simply referred to as a fuel injection valve) I attached to the intake pipe 1 has a fuel injection portion 5 at the front end, a fuel inlet cylinder portion 6 at the rear end, and a fuel injection portion at the intermediate portion. A coil portion 11 having a diameter larger than that of the portion 5 and the fuel inlet tube portion 6 is provided, and a cushion / seal member 4 made of an elastic material such as rubber is mounted on the outer periphery of the base of the fuel injection portion 5, and the fuel inlet tube An O-ring 8 is attached to the seal groove 7 formed on the outer periphery of the portion 6.

  The coil portion 11 includes a coil 9 that surrounds the fixed core 14 of the fuel injection valve I, and a synthetic resin coating layer 10 that is molded so as to embed the coil 9. 10, a coupler 12 projecting to one side is integrally formed, and this coupler 12 accommodates and holds a current-carrying terminal 13 connected to the coil 9. An end surface of the coating layer 10 facing the fuel injection portion 5 side is a front annular shoulder portion 15, and an end surface facing the fuel inlet tube portion 6 side is a rear annular shoulder portion 16.

  The fuel injection portion 5 is fitted into the mounting hole 2 so that the cushion / seal member 4 is pushed into the annular recess 2a by the front annular shoulder 15 of the coating layer 10.

  A cushion ring 17 made of an elastic material such as rubber, which is fitted to the outer periphery of the base of the fuel inlet cylinder portion 6, is disposed in contact with the rear annular shoulder portion 16, and the fuel injection valve I is interposed through the cushion ring 17. A fuel supply cap 20 that presses and holds the fuel to the mounting hole 2 side and supplies fuel to the fuel inlet cylinder 6 is fitted into the fuel inlet cylinder 6. At this time, the O-ring 8 is in close contact with the inner peripheral surface of the fuel supply cap 20.

  The fuel supply cap 20 is made of synthetic resin and has a cylindrical shape. A support arm 21 is provided on one side of the fuel supply cap 20, and a fuel joint 22 is integrally provided on the other side. The support arm 21 is inserted into the bolt hole 23. The inserted bolt 24 is screwed and tightened into a screw hole 26 of a mounting boss 25 formed at a predetermined position of the intake pipe 1 to be fixed to the predetermined position of the intake pipe 1. At this time, a set load in the compression direction is applied to the cushion / seal member 4 and the cushion ring 17, whereby the fuel injection valve I is elastically supported between the intake pipe 1 and the fuel supply cap 20.

  A fuel conduit for guiding fuel discharged from a fuel pump (not shown) is connected to the fuel joint 22.

  As shown in FIG. 1 to FIG. 3A, the rear annular shoulder portion 16 includes a first semicircular shoulder portion 16a extending over one half circumference of the coil portion 11, and the first semicircular shoulder portion. A second semicircular shoulder portion 16b that is shifted forward with respect to 16a and extends over the other half circumference of the coil portion 11 is connected to the first and second semicircular shoulder portions 16a and 16b. The coupler 12 is disposed in the vicinity of the first semicircular shoulder 16a.

  On the other hand, the front end surface of the cushion ring 17, that is, the end surface on the side facing the rear annular shoulder portion 16, is in contact with the first and second semicircular shoulder portions 16a and 16b, respectively. The end surfaces 17a and 17b and a stopper surface 17c that rises so as to connect the semicircular end surfaces 17a and 17b. The rising wall 16c and the stopper surface 17c come into contact with each other, so that the fuel injection valve I and The relative rotation of the cushion ring 17 is prevented. Thus, the standing wall 16 c and the stopper surface 17 c serve as positioning means 27 for defining the relative position between the coupler 12 of the fuel injection valve I and a one-way seal portion 31 described later provided on the cushion ring 17.

  The cushion ring 17 has a superior arc shape between the cushion portion 30 that supports the clamping force between the rear annular shoulder portion 16 and the fuel supply cap 20, and an inferior arc shape between both peripheral ends of the cushion portion 30. The one-way seal portion 31 is integrally connected, and the one-way seal portion 31 is disposed in the region of the second semicircular end surface 17b opposite to the coupler 12.

  As clearly shown in FIGS. 2 and 4 (A), the one-way seal portion 31 is fitted to the outer periphery of the fuel inlet tube portion 6 and abuts against the second semicircular shoulder portion 16b. An arc-shaped seal base portion 31a having a thickness smaller than that of the cushion portion 30, and an arc-shaped and flexible shape that protrudes from the rear end of the seal base portion 31a toward the rear and expands toward the rear and is in close contact with the front end surface of the fuel supply cap 20. The sealing lip 31b. In other words, the seal lip 31b is formed to be inclined rearward and outward. The inside of the seal lip 31b communicates with the inside of the fuel supply cap 20, and the front opening 20a inside the fuel supply cap 20 is formed in a tapered shape so that the communication is smooth.

  4 (B) and 4 (C) show a modification of the one-way seal portion 31. In the figure, portions corresponding to the one-way seal portion 31 in FIG. A description of the configuration is omitted.

  Next, the operation of this embodiment will be described.

  In attaching the fuel injection valve I to the intake pipe 1, first, the fuel injection part 5 of the fuel injection valve I is fitted into the attachment hole 2 of the intake pipe 1 and the front annular shoulder 15 of the covering layer 10 cushions the The seal member 4 is pushed into the annular recess 2a to seal around the fuel injection part 5.

  Next, the cushion ring 17 is fitted to the outer periphery of the base of the fuel inlet cylinder portion 6, and the first and second semicircular end surfaces 28 a and 28 b are connected to the first and second semicircular shoulder portions 16 a of the coil portion 11. , 16b, and the rotation stopper surface 28c is opposed to the upright wall 16c. Thereafter, the fuel supply cap 20 is fitted on the outer periphery of the fuel inlet cylinder 6, and the inner peripheral surface of the fuel supply cap 20 is brought into close contact with the O-ring 8.

  The support arm 21 of the fuel supply cap 20 is attached to the mounting boss 25 of the intake pipe 1 with a bolt 24 while pressing the fuel supply cap 20 forward to apply a set load in the compression direction to the cushion / seal member 4 and the cushion ring 17. Secure with.

  After such assembly, air is pumped to the fuel supply cap 20 in order to check whether the O-ring 8 is forgotten to be attached to the fuel inlet cylinder 6 or whether the O-ring 8 is damaged. Thus, when the O-ring 8 is forgotten to be installed or the O-ring 8 is damaged, the air pressure fed to the fuel supply cap 20 leaks to the cushion ring 17 side along the inner peripheral surface of the fuel supply cap 20. Since the inner surface of the seal lip 31b of the one-way seal portion 31 is pressed, the seal lip 31b inclined rearward and outward is outward with the seal base portion 31a as a fulcrum as shown by a chain line in FIG. Bending away from the front end face of the fuel supply cap 20, the leaked air flows out from the distant place, and when the outflow is detected, it is determined that the O-ring 8 is forgotten to be installed or the O-ring 8 is damaged and reassembled. I do. If there is no air outflow from the seal lip 31b, it is determined that neither the O-ring 8 is forgotten nor the O-ring 8 is damaged. The outflow of air from the seal lip 31b is detected by a tactile sensation of a pressure sensor or an inspector. At the time of this inspection, since the arc-shaped seal base 31a of the one-way seal portion 31 is fitted to the outer periphery of the fuel inlet cylinder portion 6 together with the cushion portion 30, the displacement of the cushion ring 17 can be prevented.

  On the other hand, when cleaning water or dust is blown from the outside to the one-way seal portion 31 of the cushion ring 17 in a state where the intake pipe 1 is attached to the engine, the pressure of the cleaning water or dust is This acts on the seal lip 31b inclined outward and in the direction in which the front end surface of the fuel supply cap 20 is in close contact with the front end surface of the fuel supply cap 20, so that the seal lip 31b is kept closed and fuel supply such as cleaning water and dust is supplied. Intrusion into the cap 20 can be prevented. Therefore, the one-way seal part 31 has a function of a one-way valve that opens by an internal pressure and maintains a closed state by an external pressure.

  By the way, the cushion ring 17 is integrally connected to the cushion portion 30 which forms a superior arc shape and supports the clamping force between the rear annular shoulder portion 16 and the fuel supply cap 20 and an inferior arc shape. Since it is composed of the direction seal portion 31, the seal lip 31b is provided with flexibility suitable for a one-way valve function, and the cushion portion 30 is provided with rigidity suitable for elastic support of the fuel injection valve I. Accordingly, the cushion ring 17 can exhibit a stable elastic support function for the fuel injection valve I while having the one-way seal portion 31.

  Further, a positioning means 27 is provided between the fuel injection valve I and the cushion ring 17 so as to define the position of the one-way seal portion 31 in the fuel injection valve I at a predetermined position opposite to the coupler 12. The position of 31 can be immediately known on the basis of the coupler 12, and the outflow of air from the one-way seal portion 31 can be surely confirmed at the time of inspection, which improves the reliability of inspection and the work efficiency. Can contribute.

  Further, when the coating layer 10 of the coil part 11 is formed, the first semicircular shoulder part and the first semicircular shoulder part 16a are arranged so as to be shifted forward with respect to the rear annular shoulder part 16. Two semicircular shoulders 16b and an upstanding wall 16c standing so as to connect between the first and second semicircular shoulders 16a, 16b are formed. As the front end face, the first and second semicircular end faces 17a and 17b that are in contact with the first and second semicircular shoulder portions 16a and 16b, respectively, and the semicircular end faces 17a and 17b are erected so as to be connected. The stopper surface 17c is formed, and the standing wall 16c and the stopper surface 17c are in contact with each other to form a positioning means 27 that defines the relative position of the coupler 12 and the one-way seal portion 31, so that the positioning means 27 , Coating layer 10 Can be obtained with molding of fine cushion ring 17, requires without providing special positioning means, it is possible to suppress the cost increase.

  As mentioned above, although the Example of this invention was described, this invention is not limited to it, A various design change is possible in the range which does not deviate from the summary. For example, the mounting hole 2 can be provided in the intake pipe of the engine. The present invention can also be implemented for a multi-cylinder engine.

I ... Fuel injection valve 2 ... Mounting hole 5 ... Fuel injection part 6 ... Fuel inlet cylinder part 8 ... O-ring 10 ... Cover Layer 11 ... Coil part 12 ... Coupler 16 ... Ring shoulder (back ring shoulder)
16a ... first semicircular shoulder 16b ... second semicircular shoulder 16c ... standing wall 20 ... fuel supply cap 27 ... positioning means 30 ... cushion part 31 ··· One-way seal portion 31a ··· Seal base portion 31b ··· Seal lip

Claims (5)

A fuel injection valve (I) supporting structure having a fuel injection portion (5) at a front end, a fuel inlet tube portion (6) at a rear end, and a rearward annular shoulder portion (16) at an intermediate portion, the fuel inlet tube An O-ring (8) is mounted on the outer periphery of the portion (6), and a cushion ring (17) fitted to the outer periphery of the fuel inlet tube portion (6) is disposed in contact with the annular shoulder portion (16). The fuel injection part (5) is fitted into the mounting hole (2) of the engine, and a fuel supply cap is fitted to the outer periphery of the fuel inlet tube part (6). The inner periphery of the fuel supply cap (20) The O-ring (8) is brought into close contact with the surface, and the fuel injection valve (I) is supported by pressing the cushion ring (17) toward the mounting hole (2) on the front end surface of the fuel supply cap (20). In what I did,
A unidirectional seal portion (31) is formed on at least a part of the cushion ring (17) to enable pressure movement in only one direction from the inside of the fuel supply cap (20) to the outside of the cushion ring (17). A fuel injection valve support structure. The fuel injection valve support structure according to claim 1,
The cushion ring (17) is formed in a superior arc shape and a cushion portion (30) for supporting a clamping force between the annular shoulder portion (16) and the fuel supply cap (20), and the cushion portion is formed in an inferior arc shape. (30) The fuel injection valve support structure characterized by comprising the one-way seal portion (31) integrally connecting the two circumferential ends. In the fuel injection valve support structure according to claim 2,
The one-way seal portion (31) is fitted to the outer periphery of the fuel inlet tube portion (6) together with the cushion portion (30), and a seal base portion (31a) is brought into contact with the annular shoulder portion (16). A seal lip (31b) that protrudes from the rear end of the seal base (31a) so as to increase in diameter toward the rear is in contact with the front end surface of the fuel supply cap (20). A fuel injection valve support structure, wherein the pressure in the fuel supply cap (20) is released to the outside by bending outward with the seal base (31a) as a fulcrum. In the fuel injection valve support structure according to claim 2 or 3,
A positioning means (27) for regulating the position of the one-way seal portion (31) in the fuel injection valve (I) to be constant is provided between the fuel injection valve (I) and the cushion ring (17). The fuel injection valve support structure. The fuel injection valve support structure according to claim 4,
The annular shoulder portion (16) is formed in an intermediate portion of the fuel injection valve (I) and is covered with a synthetic resin coating layer (10), and a coil portion having a diameter larger than that of the fuel inlet tube portion (6). (11) Consists of the rear end, and the annular shoulder (16) is axially displaced with respect to the first semicircular shoulder (16a) and the first semicircular shoulder (16a). On the other hand, the second semicircular shoulder (16b) disposed and the upright wall (16c) standing up so as to connect the first and second semicircular shoulders (16a, 16b), First and second semicircular end surfaces (17a, 17b) that contact the front end surface of the cushion ring (17) with the first and second semicircular shoulder portions (16a, 16b), respectively, and these semicircular portions And a stopper surface (17c) standing so as to connect between the end faces (17a, 17b), and a fuel injection valve (I) The positioning means (27) is constituted by the upright wall (16c) and the stopper surface (17c) which are in contact with each other so as to prevent relative rotation of the cushion ring (17). Construction.

Images