JP2009103024A - Mounting structure of fuel injection valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mounting structure of a fuel injection valve facilitating the mounting operation of the fuel injection valve without requiring a special positioning member for positioning the turning of the fuel injection valve. <P>SOLUTION: In the mounting structure of the fuel injection valve I held by a holding part 10 integrally formed projecting from an intake pipe 2 or a cylinder head through a joint cap 30, the holding part 10 is a cylindrical holding part formed in cylindrical shape surrounding the side of a body of the fuel injection valve I by a cylindrical wall, and a part of the cylindrical wall of the cylindrical holding part 10 is provided with a lacking part 15 allowing an electric coupler Ic, projected to the side from the body of the fuel injection valve I, to be fittingly inserted and projected outside. The lacking part 15 is formed to be recessed in the generating line direction of the peripheral surface from an open end face 13s of the cylindrical wall. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel injection valve mounting structure for injecting and supplying fuel to an intake system of an internal combustion engine.

  There is an example in which a holding device that holds a fuel injection valve disposed in an intake passage of an internal combustion engine is formed integrally with an intake passage (see, for example, Patent Document 1).

JP 2003-49740 A

  The holding device disclosed in Patent Document 1 has a columnar bracket that protrudes from the vicinity of a mounting hole of an intake passage to which a tip portion having a fuel injection port of a fuel injection valve is fitted, and is formed at the tip of the bracket. A fixed holder that is formed in an annular shape and holds a base end portion having a fuel inlet of the fuel injection valve via a joint cap is provided.

  Therefore, the fuel injection valve has a distal end fitted into the mounting hole of the intake passage, a base end is held by a fixed holder at the distal end of the bracket via the joint cap, and most of the fuel injection valve excluding the distal end and the base end is An electrical coupler that is mounted in an exposed state and branches off from the exposed central portion of the fuel injection valve so as to obtain control power projects laterally.

  In this way, the fuel injection valve has an electric coupler projecting laterally from the main body thereof, and thus cannot pass through the annular fixed holder, so the side of the mounting space between the mounting hole and the fixed holder Since it is necessary to assemble from the side, it is not easy to assemble, and then the fuel injection valve is attached by engaging the joint cap with the fixed holder and covering the base end of the fuel injection valve.

Therefore, it is not easy to attach the fuel injection valve to the holding device.
Further, unless positioning of the rotation position about the axis of the fuel injection valve is particularly provided, the rotation is free, the fuel introduction port and the fuel introduction path of the joint cap do not coincide, and the orientation of the electrical coupler is not determined.

  Further, since the bracket for holding the fuel injection valve has a columnar shape, the bracket must be formed relatively thick in order to ensure the holding strength.

  The present invention has been made in view of the above points, and the object of the present invention is that the fuel injection valve can be easily attached and does not require a special positioning member for rotational positioning of the fuel injection valve. It is in providing a mounting structure.

  In order to achieve the above object, according to the first aspect of the present invention, there is provided a fuel injection side end portion of the fuel injection valve in a mounting hole formed in a predetermined portion of an intake pipe or a cylinder head for leading intake air to a combustion chamber of an internal combustion engine. A fuel that is inserted and held by a holding portion that is integrally formed on the intake pipe or the cylinder head via a joint cap that covers the fuel introduction side end of the fuel injection valve. In the mounting structure of the injection valve, the holding portion is a cylindrical holding portion formed in a cylindrical shape in which a cylindrical wall surrounds the side of the main body of the fuel injection valve, and one of the cylindrical walls of the cylindrical holding portion. A deficient portion that can be inserted into and protrudes outward from the main body of the fuel injection valve into the portion is protruded from the opening end surface of the cylindrical wall in the direction of the generatrix of the peripheral surface. A fuel injection valve mounting structure formed.

  According to a second aspect of the present invention, in the fuel injection valve mounting structure according to the first aspect of the present invention, a plurality of engaging claws are formed on the outer periphery of the joint cap so as to project radially, and are formed on the inner surface of the cylindrical wall of the cylindrical holder. A plurality of transverse grooves for engaging the engaging claws are formed in the circumferential direction, and the longitudinal grooves are opened from the end of the transverse groove toward the opening end face of the cylindrical wall to the opening end face. A plurality of circumferential surfaces are formed so as to be directed in the direction of the generatrix.

  According to a third aspect of the present invention, in the fuel injection valve mounting structure according to the second aspect, the deficient portion also serves as one of the longitudinal grooves.

  According to a fourth aspect of the present invention, in the fuel injection valve mounting structure according to the third aspect, the lateral groove is formed in communication with the deficient portion.

  According to a fifth aspect of the present invention, in the fuel injection valve mounting structure according to the fourth aspect of the present invention, the upper surface facing the lower side of the lateral groove has a plane perpendicular to the generatrix of the peripheral surface of the cylindrical holding portion. It is formed, and a part communicating with the defect portion forms an inclined surface inclined obliquely upward toward the outside.

  According to a sixth aspect of the present invention, in the fuel injection valve mounting structure according to any one of the second to fifth aspects, the joint cap has a flange portion formed above the engagement claw, and the When the joint cap is engaged and held by the cylindrical holding portion, an elastic member is interposed between the opening end surface of the cylindrical holding portion and the flange portion of the joint cap, and the joint cap is provided by the elastic member. Is biased upward with respect to the cylindrical holding portion.

  According to a seventh aspect of the present invention, in the fuel injection valve mounting structure according to the sixth aspect, the elastic member locked to the locking portion of the opening end surface of the cylindrical holding portion and the flange portion of the joint cap A concave portion and a convex portion are respectively formed in predetermined portions facing each other, and the joint cap is positioned at a predetermined rotational position with respect to the cylindrical holding portion by engagement of the concave portion and the convex portion, and is held in engagement. It is characterized by being.

  According to an eighth aspect of the present invention, in the fuel injection valve mounting structure according to the sixth or seventh aspect, the opening end surface of the cylindrical holding portion is entirely covered by the flange portion.

  The invention according to claim 9 is the fuel injection valve mounting structure according to any one of claims 1 to 8, wherein the joint cap is engaged and held by the cylindrical holding portion. The fuel introduction pipe protruding from the joint cap and connected to the fuel pipe is located above the opening end face of the cylindrical holding portion.

  A tenth aspect of the present invention is the fuel injection valve mounting structure according to any one of the first to ninth aspects, wherein the cylindrical holding portion is mounted on the intake pipe or the cylinder head. The water drainage hole is formed in the lowest position of the inclined cylindrical holding part.

  According to the mounting structure of the fuel injection valve according to claim 1, the holding portion is a cylindrical holding portion formed in a cylindrical shape in which a cylindrical wall surrounds the side of the main body of the fuel injection valve, and the cylindrical holding portion. A part of the cylindrical wall of which the electrical coupler protruding laterally from the main body of the fuel injection valve is inserted and protruded to the outside is a defect portion extending from the opening end surface of the cylindrical wall in the direction of the generatrix. Since it is formed so as to be recessed, it can be easily assembled by inserting the fuel injection valve in the axial direction with an electrical coupler corresponding to the missing part of the cylindrical holding part, and the installation work of the fuel injection valve To make it easier.

Since the electrical coupler is fitted into the missing portion of the cylindrical holding portion and positioned in the rotational direction together with the fuel injection valve, no special member is required for positioning.
Since the cylindrical holding portion surrounds the main body of the fuel injection valve, the fuel injection valve is sufficiently protected and the operating noise of the fuel injection valve can be blocked.
The holding portion protruding from the intake pipe forms a cylindrical shape in which the cylinder wall surrounds the main body of the fuel injection valve. Therefore, even if the cylindrical holding portion is a relatively thin cylindrical wall, it is strong and rigid. Can be secured, and the fuel injection valve can be compactly attached.

  According to the mounting structure of the fuel injection valve according to claim 2, a plurality of lateral grooves for engaging a plurality of engaging claws formed on the outer periphery of the joint cap on the inner surface of the cylindrical wall of the cylindrical holding portion. Since the vertical groove is formed in the direction of the generatrix of the peripheral surface by opening to the opening end surface of the cylindrical wall from the end of the horizontal groove toward the opening end surface of the cylindrical wall, The joint cap is inserted into the cylindrical holding portion in the axial direction so that the engaging claw of the joint cap is fitted into the vertical groove of the cylindrical holding portion, and then the engaging claw communicates with the vertical groove of the cylindrical holding portion. By rotating the joint cap with respect to the cylindrical holding portion so as to engage with the cylindrical holding portion, the joint cap can be easily engaged and held with the cylindrical holding portion.

The fuel injection valve can be attached more easily by inserting the fuel injection valve into the cylindrical holding portion and rotating and holding the joint cap in a state where the joint cap is pre-assembled with the fuel injection valve. .
The attachment of the fuel injection valve to the cylindrical holding portion does not require a fastening bolt or the like, facilitates the attachment work, and does not provide the fastening boss portion, so that the fuel injection valve can be held compactly.

  According to the fuel injection valve mounting structure of the third aspect, since the missing portion of the cylindrical holding portion also serves as one of the vertical grooves that guide the engaging claws of the joint cap, the shape of the cylindrical holding portion is simplified. And become compact.

  According to the fuel injection valve mounting structure of the fourth aspect, since the lateral groove is formed to communicate with the missing part, the lateral groove opens to the outer peripheral surface of the cylindrical holding part, and the opening communicates with the missing part. Therefore, when the cylindrical holding portion is molded together with the intake pipe, the lateral groove can be easily molded by the slide mold.

According to the fuel injection valve mounting structure according to claim 5, the upper surface of the lateral groove facing downwardly forms a plane perpendicular to the generatrix of the peripheral surface of the cylindrical holding portion. The engagement of the engagement claw of the joint cap to the tube can be ensured, and the cylindrical holding portion can securely hold the joint cap.
In addition, a part that communicates with the chipped portion of the upper surface of the lateral groove, which is mostly a plane perpendicular to the generatrix, forms an inclined surface that is inclined obliquely upward toward the outside. In doing so, the mold and the slide mold are smoothly combined, and the engaging claw of the joint cap can be easily engaged from the vertical groove (defect portion) to the horizontal groove, facilitating the assembling work.
It should be noted that the direction in which the fuel injection valve is inserted into the cylindrical holding portion is downward and the opposite is upward.

  According to the fuel injection valve mounting structure of claim 6, when the joint cap is engaged and held by the cylindrical holding portion, the elastic member is provided between the opening end surface of the cylindrical holding portion and the flange portion of the joint cap. Since the joint cap is urged upward with respect to the cylindrical holding portion by the elastic member, the joint claw urged upward has an engaging claw engaged with the lateral groove of the cylindrical holding portion. Since it is pressed against the upper surface of the lateral groove, the frictional resistance increases and the rotation of the joint cap is suppressed to stabilize the engagement.

  According to the fuel injection valve mounting structure of the seventh aspect, the concave portion and the convex portion are formed in the predetermined portions of the elastic member and the flange portion of the joint cap that are locked to the locking portion of the opening end surface of the cylindrical holding portion. Since the joint cap is positioned and engaged and held with respect to the cylindrical holding portion by fitting the concave portion and the convex portion to each other, the joint cap for the cylindrical holding portion is provided. Can be easily and reliably aligned to a predetermined rotational position.

  According to the fuel injection valve mounting structure of the eighth aspect, since the entire opening end surface of the cylindrical holding portion is covered by the flange portion, water or sand or the like is formed in the opening of the opening end surface of the cylindrical holding portion. In addition to preventing foreign matter from entering, the operating noise of the fuel injection valve can be more reliably blocked.

  According to the fuel injection valve mounting structure of the ninth aspect, the fuel introduction pipe protruding from the joint cap and connected to the fuel pipe in a state where the joint cap is engaged and held by the cylindrical holding portion has a cylindrical shape. Since it is located above the opening end surface of the holding part, the direction of the fuel introduction pipe of the joint cap can be freely set.

  According to the fuel injection valve mounting structure according to claim 10, the cylindrical holding portion is inclined in a state where it is attached to the intake pipe or the cylinder head, and a drain hole is provided at the lowest position of the inclined cylindrical holding portion. Therefore, the water that has entered the cylindrical holding portion can be discharged to the outside through the drain hole.

Hereinafter, an embodiment according to the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view of an intake pipe 2 connected to an intake port opening end portion of a cylinder head 91c of an internal combustion engine according to the present embodiment and the vicinity thereof.

The intake pipe 2 has a curved intake passage 2p, branches to the curved outer side, a cylindrical holding portion 10 projects, and a fuel injection valve I is fitted into the cylindrical holding portion 10 and is held via a joint cap 30. Is done.
A throttle body 3 is connected to the upstream end of the intake pipe 2.

The present intake pipe 2 is made of a PPS (polyphenylene sulfide) resin that is integrally injection-molded by a mold together with the cylindrical holding portion 10 and has excellent heat resistance and high rigidity.
The structure of the intake pipe 2 will be described below with reference to FIGS.

A mounting flange 21 is formed at the downstream end (cylinder head 1 side) of the curved intake passage 2p of the intake pipe 2, and a metal collar 4 is embedded in a pair of mounting bosses 2lb of the mounting flange 21. (See FIG. 9).
On the other hand, an opening end portion on the upstream side (throttle body 3 side) of the intake passage 2p of the intake pipe 2 is formed with a mounting flange 2u, and a metal female screw member 5 is embedded in a pair of mounting boss portions 2ub of the mounting flange 2u. (See FIG. 10).

Therefore, the intake pipe 2 is connected to the mounting seat at the downstream opening end of the intake port of the cylinder head 1 by connecting the downstream mounting flange 21 to the metal collar 4 of the mounting boss 2lb through the bolt 4B. Fastened and attached to the cylinder head 1 (see FIG. 1).
The load due to tightening of the bolt 4B is received by the metal collar 4, and the resin mounting boss 2lb itself is not subjected to fastening force and has no trouble such as breakage, and can be firmly tightened and fixed firmly.

Further, the downstream opening end of the throttle body 3 is connected to the upstream mounting flange 2u of the intake pipe 2, and the mounting boss 3b on the throttle body 3 side is aligned with the mounting boss 2ub of the mounting flange 2u. Then, the throttle body 3 is attached by passing the bolt 5B from the throttle body 3 side through the attachment boss 3b and screwing and fastening to the metal female screw member 5 of the attachment boss 2ub (see FIG. 1).
Since the bolt 5B is screwed into the metal female screw member 5 and tightened, the resin mounting boss portion 2ub itself is not applied with a fastening force and has no trouble such as breakage, and can be tightened and firmly tightened. .

As shown in FIG. 1, a throttle drum 3d for opening and closing a throttle valve in the intake passage is fitted to the throttle body 3 on a throttle rotating shaft 3a protruding sideways.
A throttle wire is wound around the throttle drum 3d, and when the throttle wire is pulled, the throttle valve rotates together with the throttle drum 3d to adjust the throttle valve opening.

The cylindrical holding portion 10 formed integrally with the intake pipe 2 has a lower cylindrical wall 11 whose diameter is reduced at the bottom of the central cylindrical wall 12 that is longest in the central axis direction (bus line direction). The upper cylindrical wall 13 has a flat upper cylindrical wall 13 with a larger outer diameter, the lower cylindrical wall 11 is integrated with the curved outer portion of the intake pipe 2, and the cylindrical holding portion 10 is formed to project from the intake pipe 2. ing.
The central axis C of the cylindrical holding portion 10 intersects the central curve of the intake passage 2p within the intake port of the cylinder head 1.

  Inside the cylindrical holding portion 10, the central cylindrical wall 12 and the upper cylindrical wall 13 are formed to have the same inner diameter. In the lower cylindrical wall 11, the middle diameter portion 11a on the central cylindrical wall 12 side and the small diameter portion 11b on the intake passage 2p side. The mounting hole is formed by reducing the diameter to two stages, and the mounting hole communicates with the intake passage 2p.

The cylindrical holding portion 10 has a notched portion 15 cut out at a part of the central cylindrical wall 12 and the upper cylindrical wall 13.
The deficient portion 15 is formed in a rectangular shape so as to protrude from the opening end surface 13 s of the upper cylindrical wall 13 to the central cylindrical wall 12 in the generatrix direction (center axis C direction) of the peripheral surface.

The missing portion 15 has a rectangular shape that has a width in the circumferential direction smaller than the inner diameters of the upper cylindrical wall 13 and the central cylindrical wall 12 and a length in the axial direction (central axis C) that covers the entire upper cylindrical wall 13 and the central cylindrical wall 12. Eggplant.
The circumferential width of the missing portion 15 is substantially equal to the width of the electrical coupler Ic protruding laterally from the main body Ib of the fuel injection valve I.

Two transverse grooves 17 and 18 are formed on the inner surface of the upper cylindrical wall 13 whose outer diameter of the cylindrical holding portion 10 is enlarged so as to be oriented in the circumferential direction.
In the cross-sectional view of FIG. 8, assuming a CP direction extending from the central axis C toward the center of the defect 15, one lateral groove 17 is short and one end communicates with the defect 15. 17s has a plane parallel to the CP direction and a partial arc surface on the back side (the side opposite to the defective portion 15).

The other lateral groove 18 is long and has one end communicating with the defect 15, and the inner side surface 18 s is composed of a plane parallel to the CP direction and a long arc surface facing the inner side surface 17 s. The arc surface of 18 s extends in the CP direction toward the lateral groove 17 and extends to the partition portion 19 between the lateral groove 17.
The partition portion 19 is formed in a direction rotated 135 degrees clockwise in the CP direction about the central axis C in FIG.

Referring to FIG. 6, upper surfaces 17u and 18u of lateral grooves 17 and 18 form a vertical surface with respect to central axis C, and lower surfaces 17l and 18l of lateral grooves 17 and 18 have portions corresponding to each other in the CP direction. It has an inclined surface that is slightly inclined downward.
Further, the end surfaces of the lateral grooves 17 and 18 that communicate with the missing portions 15 of the upper surfaces 17u and 18u form inclined surfaces 17ue and 18ue that are inclined upward in the CP direction.

The vertical groove 16 opens from the end of the circular groove 18 of the upper cylindrical wall 13 toward the opening end face 13s of the upper cylindrical wall 13 toward the opening end face 13s, and the vertical groove 16 is in the direction of the generatrix (center axis C direction). Therefore, the vertical groove 16 and the horizontal groove 18 are bent and communicated in an L shape.
The circumferential width of the longitudinal groove 16 is substantially the same as the circumferential width of the missing portion 15.
The defective portion 15 also serves as one of the vertical grooves, and the lateral grooves 17 communicate with each other so as to be bent in an L shape.
Note that the missing portion 15 communicates with the other lateral groove 18.

The lower part of the deficient portion 15 is somewhat cut in one circumferential direction (the one corresponding to the upper lateral groove 18) to form a drain hole 15w.
When the intake pipe 2 is attached to the cylinder head 1, the cylindrical holder 10 that branches off and protrudes from the intake pipe 2 has a central axis C slightly inclined from the vertical line, and the lowermost part of the inclined central cylindrical wall 12. The drain hole 15w is located at the position.
Therefore, the water that has entered the cylindrical holding portion 10 can be easily discharged to the outside from the drain hole 15w.

On the opening end face 13s of the upper cylindrical wall 13 of the cylindrical holding portion 10, shallow fitting recesses 13a and 13b having a rectangular bottom are formed at symmetrical positions with respect to the CP direction, and as shown in FIGS. In the fitting recesses 13a and 13b, spring members 20 and 21 which are elastic plates curved so as to bulge out at the center are fitted.
Concave portions 20a and 21a are formed at the curved uppermost portions of the spring members 20 and 21, and the concave portions 20a and 21a at the uppermost portions are upper portions when the spring members 20 and 21 are fitted into the fitted concave portions 13a and 13b. The cylindrical wall 13 protrudes upward from the opening end surface 13s.

The intake pipe 2 provided with the cylindrical holding portion 10 as described above is manufactured by injection-molding PPS resin into a mold.
The cylindrical holding portion 10 is formed by injection molding at a place where a slider die for forming the lateral grooves 17 and 18 is inserted and combined with the inner and outer molds from the defect portion 15 side.

  The two transverse grooves 17 and 18 communicate with the defect 15, and the upper surfaces 17 u and 18 u of the transverse grooves 17 and 18 are mostly end surfaces that are perpendicular to the central axis C and communicate with the defect 15. Are formed inclined surfaces 17ue and 18ue inclined upward in the CP direction, and the lower surfaces 17l and 18l are inclined surfaces in which the corresponding portions are slightly inclined downward in the CP direction. The slider mold can be smoothly inserted and combined with the inner and outer molds of the cylindrical holder 10 from the CP direction side, and the lateral grooves 17 and 18 can be easily formed by the slider mold.

Referring to FIG. 11, the fuel injection valve I inserted and held in the cylindrical holding portion 10 has a small diameter portion of the lower cylindrical wall 11 that extends downward from the main body Ib having an outer diameter slightly smaller than the inner diameter of the central cylindrical wall 12. A fuel injection side end Ie having an outer diameter substantially equal to the inner diameter of 11b is reduced in diameter and extended, and the diameter of the fuel injection side end Ii is extended upward from the main body Ib.
An electrical coupler Ic for branching from the main body Ib to obtain control power projects laterally.

A ring-shaped seal member 25 is fitted to the fuel injection side end Ie extending below the fuel injection valve I, and is fitted into a mounting hole formed by the middle diameter portion 11a and the small diameter portion 11b of the lower cylindrical wall 11 of the cylindrical holding portion 10. Insert.
The seal member 25 is fitted to the middle diameter portion 11a of the lower cylindrical wall 11 to seal between the small diameter portion 11b and the inside of the central cylindrical wall 12 (see FIG. 16).

  Further, an O-ring 26 is fitted in an annular groove in the vicinity of the upper end of the fuel introduction side end Ii extending above the fuel injection valve I, and a joint cap 30 is put on the upper end (FIGS. 11 and 11). 12).

  The joint cap 30 is made of a resin and is integrally formed with a cap portion 31 that covers the fuel introduction side end portion Ii of the fuel injection valve I and a fuel introduction pipe 32 that extends from the cap portion 31 in an elongated manner. .

The cap portion 31 has a bottomed cylindrical shape, and the inner diameter thereof is substantially equal to the outer diameter of the fuel introduction side end portion Ii extending above the fuel injection valve I.
The central portion of the upper wall of the cap portion 31 bulges upward to form a base end portion of the fuel introduction pipe 32. From the base end portion, the fuel introduction pipe 32 is perpendicular to the cylindrical central axis of the cap portion 31. It extends long.

The bottom end opening of the bottomed cylindrical cap portion 31 warps outward to form a skirt, and a pair of engaging claws 31a and 31b are formed so as to protrude symmetrically from each other in the radial direction.
One engaging claw 31b protrudes in the same direction as the fuel introduction pipe 32, and the other engaging claw 31a protrudes 180 degrees opposite to the engaging claw 31b and is in the same axial position.

The leading edges of the engaging claws 31a and 31b have the same circular arc surface, and the outer diameter thereof is substantially equal to the inner diameter of the lateral grooves 17 and 18 formed on the inner surface of the upper cylindrical wall 13 of the cylindrical holding portion 10.
The circumferential widths of the engaging claws 31a and 31b are slightly smaller than the circumferential widths of the missing portion 15 and the longitudinal groove 16, and the thickness is slightly smaller than the groove widths of the lateral grooves 17 and 18.

Further, like the engaging claws 31a and 31b at the lower part from the upper part of the cap part 31, flange parts 31p and 31q are formed so as to protrude at the same axial position.
The flange portion 31p has a substantially the same shape above the engaging claw 31a and has a slightly larger protruding amount, and the flange portion 31q has a substantially the same shape above the engaging claw 31b and has a slightly larger protruding amount. At the same time, the fuel introduction pipe 32 is partially fused and integrated.

The interval between the flange portion 31p and the engaging claw 31a and the interval between the flange portion 31q and the engaging claw 31b are the same, and the upper surfaces 17u and 18u of the lateral grooves 17 and 18 of the upper cylindrical wall 13 in the cylindrical holding portion 10 It is slightly larger than the vertical width between the open end face 13s of the upper cylindrical wall 13.
And on the lower surface of the engaging claws 31p, 31q, convex portions 31pa, 31qa which are long and narrow in the radial direction are formed at predetermined positions.

The joint cap 30 has the above-described structure, and the fuel injection valve I is attached to the cylindrical holding portion 10 in a state where the cap portion 31 is put on the fuel introduction side end Ii of the fuel injection valve I.
Hereinafter, a procedure for attaching the fuel injection valve I to the cylindrical holder 10 will be described with reference to FIGS.

  An O-ring 26 is fitted in an annular groove of the fuel introduction side end Ii extending above the fuel injection valve I (see FIG. 11), and the cap portion 31 of the joint cap 30 is fitted to the fuel introduction side end Ii. And put it in a pre-assembled state (see FIG. 12).

  The fuel introduction side end Ii of the fuel injection valve I is fitted into the bottomed cylindrical cap portion 31 of the joint cap 30 and sealed by the O-ring 26 (see FIG. 16). As shown in FIG. 12, initially, the engaging claw 31a and the flange portion 31p of the cap portion 31 of the joint cap 30 face in the direction in which the electric coupler Ic of the fuel injection valve I protrudes. In the opposite direction, the fuel injection valve I and the joint cap 30 are set and assembled in a rotating position so that the engaging claw 31b, the flange portion 31q, and the fuel introduction pipe 32 face.

  Next, the fuel injection valve I, which is covered with the joint cap 30 and thus assembled, is inserted into the cylindrical holding portion 10 that branches off from the intake pipe 2 and protrudes. At this time, the central axis C of the cylindrical holding portion 10 is inserted. The fuel injection valve I is inserted in the axial direction so that the center axis of the fuel injection valve I coincides with the electrical coupler Ic of the fuel injection valve I corresponding to the missing portion 15 of the cylindrical holder 10.

A ring-shaped seal member 25 is fitted in advance to the fuel injection side end Ie extending below the fuel injection valve I.
In addition, spring members 20 and 21 are fitted in the fitting recesses 13a and 13b of the opening end face 13s of the upper cylindrical wall 13 of the cylindrical holding part 10, respectively.

  Thus, when the fuel injection valve I is inserted into the cylindrical holding portion 10, the electrical coupler Ic that protrudes laterally from the main body Ib of the fuel injection valve I is inserted into the missing portion 15 of the cylindrical holding portion 10 so that the missing portion 15 is exposed to the outside. The engaging claw 31a of the joint cap 30 is inserted into the missing portion 15, the engaging claw 31b is inserted into the longitudinal groove 16 of the upper cylindrical wall 13, and the seal member 25 fitted to the fuel injection side end Ie is connected to the lower cylindrical wall. 11 is fitted into the middle diameter portion 11a and the distal end side of the fuel injection side end portion Ie is attached to the small diameter portion 11b, and the insertion state shown in FIG. 13 is obtained.

In this inserted state, the electrical coupler Ic is inserted into the missing portion 15 and protrudes outside, so that the rotation of the fuel injection valve I is restricted with respect to the cylindrical holding portion 10 and the rotational position is fixed. .
The engaging claws 31 a and 31 b of the joint cap 30 are aligned in the axial direction with the lateral grooves 17 and 18 of the upper cylindrical wall 13 of the cylindrical holding portion 10.

  Therefore, when only the joint cap 30 is rotated clockwise as viewed from above in the axial direction while the fuel injection valve I regulated with respect to the cylindrical holding portion 10 is left as it is, the engaging claw 31a of the joint cap 30 is attached to the upper cylindrical wall 13. The engaging claw 31b enters the lateral groove 18 into the lateral groove 17 on the inner surface of the inner surface, and the flange portions 31p and 31q simultaneously rotate along the open end surface 13s of the upper cylindrical wall 13.

  In the middle of the rotation of the joint cap 30 with respect to the cylindrical holding portion 10, a flange is formed at a portion protruding above the spring members 20 and 21 fitted in the fitting recesses 13a and 13b of the opening end surface 13s of the upper cylindrical wall 13, respectively. The lower surfaces of the portions 31p, 31q are in contact with each other, the flange portions 31p, 31q are pressed upward by the elastic force of the spring members 20, 21, the joint cap 30 is urged upward, and the engaging claws 31a, 31b are formed in the lateral grooves 17, 18 Are pressed against the upper surfaces 17u and 18u.

When the joint cap 30 is rotated about 90 degrees with respect to the cylindrical holding portion 10, the convex portions 31pa and 31qa on the lower surfaces of the flange portions 31p and 31q are respectively formed on the concave portions 20a and 21a of the uppermost portions of the spring members 20 and 21. Rotating positioning is performed by fitting (see FIG. 15).
Further, the engaging claw 31a of the joint cap 30 is regulated at a rotation position of about 90 degrees by the partition part 19 between the lateral grooves 17 and 18 of the cylindrical holding part 10.

  In this way, in the state shown in FIG. 14, the fuel injection valve I is inserted and attached to the cylindrical holding part 10 via the joint cap 30, and the fuel injection is made to the cylindrical holding part 10 that branches off from the intake pipe 2 and protrudes. The electrical coupler Ic provided on the main body Ib of the valve I and the fuel introduction pipe 32 of the joint cap 30 are projected in a predetermined direction with an opening angle of 90 degrees.

  A fuel pipe is connected to the fuel introduction pipe 32 of the joint cap 30, and fuel is supplied to the fuel injection valve I through the fuel introduction pipe 32, and a connector of the control wiring is joined to the electrical coupler Ic to connect the fuel injection valve I. Is controlled to open and close, and fuel can be injected from the fuel injection side end Ie into the intake passage 2p at the controlled timing.

Since the cylindrical holding portion 10 accommodates and surrounds the main body Ib of the fuel injection valve I, the fuel injection valve I is sufficiently protected and the operation sound of the fuel injection valve I can be cut off.
Since the cylindrical holding portion 10 protruding from the intake pipe 2 has a cylindrical shape in which the central cylindrical wall 12 and the upper cylindrical wall 13 surround the main body Ib of the fuel injection valve I, the cylindrical holding portion 10 is compared. Even if the cylinder wall is thin, strength and rigidity can be ensured, and the fuel injection valve I can be compactly attached.

  A deficient portion 15 into which an electrical coupler Ic protruding from the fuel injection valve I can be inserted is formed in the cylindrical holding portion 10, and an engagement claw of the joint cap 30 is formed on the inner peripheral surface of the upper cylindrical wall 13 of the cylindrical holding portion 10. Since the vertical groove 16 (deleted portion 15) and the horizontal groove 18 (17) engaged with 31b (31a) are formed in an L-shape, the fuel injection valve I is covered with a joint cap 30 and assembled in advance. In this state, the electric coupler Ic is made to correspond to the missing portion 15 and the fuel injection valve I is inserted into the cylindrical holding portion 10, and at the same time, the engaging claw 31 b (31 a) of the joint cap 30 is inserted into the vertical groove 16 (deletion) of the cylindrical holding portion 10. The joint cap 30 is inserted into the cylindrical holding portion 10 in the axial direction so as to be fitted into the portion 15), and the joint cap 30 is rotated to engage and hold the engaging claws 31a and 31b in the lateral grooves 17 and 18. The fuel injection valve I can be easily attached.

Since the electrical coupler Ic is fitted into the missing portion 15 of the cylindrical holding portion 10 and positioned in the rotational direction together with the fuel injection valve I, no special member is required for positioning.
The attachment of the fuel injection valve I to the cylindrical holding portion 10 does not require a fastening bolt or the like, facilitates the attachment work, and does not provide a fastening boss portion, so that the fuel injection valve I can be held compactly. .
Since the missing portion 15 of the cylindrical holding portion 10 also serves as one of the longitudinal grooves, the shape of the cylindrical holding portion 10 is simplified and the size becomes more compact.

  When the joint cap 30 is engaged and held by the cylindrical holding portion 10, spring members 20 and 21 are interposed between the open end surface 13s of the cylindrical holding portion 10 and the flange portions 31p and 31q of the joint cap 30, respectively. Since the joint cap 30 is biased upward with respect to the cylindrical holding portion 10 by the spring members 20 and 21, the joint cap 30 biased upward is engaged with the lateral grooves 17 and 18 of the cylindrical holding portion 10. Since the claws 31a and 31b are pressed against the upper surfaces 17u and 18u perpendicular to the axial direction of the lateral grooves 17 and 18, the frictional resistance increases and the rotation of the joint cap 30 is suppressed to stabilize the engagement.

  Further, the spring members 20 and 21 fitted and locked in the fitting recesses 13a and 13b of the opening end surface 13s of the cylindrical holding part 10 are formed with recesses 20a and 21a at the uppermost portion protruding from the opening end surface 13s, respectively. Convex portions 31pa and 31qa are formed on the lower surface of the flange portions 31p and 31q of 30, and the flange portion 31p is formed in the concave portions 20a and 21a at the uppermost portion of the spring members 20 and 21 by the rotation of the joint cap 30 with respect to the cylindrical holding portion 10. , 31q on the lower surface of 31q and 31qa are fitted and rotationally positioned, so that the joint cap 30 can be easily and reliably aligned with the cylindrical holding portion 10 at a predetermined rotational position.

  In addition, you may form a convex part in the spring members 20 and 21, and may form a recessed part in the lower surface of the flange parts 31p and 31q.

  In a state where the joint cap 30 is engaged and held with the cylindrical holding portion 10, the fuel introduction pipe 32 protruding from the joint cap 30 and connected to the fuel pipe is positioned above the opening end surface 13 s of the cylindrical holding portion 10. Therefore, the direction of the fuel introduction pipe 32 of the joint cap 30 can be set freely.

  A partial side view of a motorcycle 70 equipped with a power unit to which the fuel injection valve mounting structure according to the present embodiment is applied will be described with reference to FIG.

The body frame of the motorcycle 70 is inclined diagonally downward from the upper part of the head pipe 72 of the entire body, and one main frame 73 extends, and a pair of left and right pivot brackets 74, 74 is fixed so as to extend downward.
At the rear of the main frame 73, a pair of left and right seat rails 75, 75 extend obliquely upward from the front from the position where the pivot brackets 74, 74 are fixed, and bend substantially horizontally while reaching the rear end.
Middle frames 76 and 76 are interposed between the bent portions of the seat rails 75 and 75 and the pivot brackets 74 and 74.

Between the pair of left and right seat rails 75, 75 of the vehicle body frame as described above, the storage box 100 and the fuel tank 102 are installed in the front-rear direction, and the seat 78 covers the storage box 100 and the fuel tank 102 so as to be freely opened and closed.
A battery 101 is disposed below the storage box 100, and a fuel pump 103 is disposed at the front of the fuel tank.

A handlebar is provided above and supported by the head pipe 72 at the front of the vehicle body, and a front fork 80 extends downward and a front wheel 81 is pivotally supported at the lower end thereof.
A rear fork 83 is pivotally supported by a pivot shaft 82 at the center of the vehicle body by a pivot shaft 82 and extends rearward. A rear wheel 84 is pivotally supported at the rear end of the rear fork 83.
Rear cushions 85 and 85 are interposed between a rear fork 83 swinging up and down about the pivot shaft 82 and the seat rails 75 and 75.

The power unit 90 is suspended below the main frame 73 and in front of the pivot brackets 74 and 74.
The power unit 90 is configured integrally with the internal combustion engine 91 in the front half and the transmission 92 in the rear half, and a chain 94 is provided between the output shaft 93 of the transmission 92 and the rear axle of the rear wheel 84. It is passed over and the rotational power of the output shaft 93 is transmitted to the rear wheel 84 via the chain 94, so that the rear wheel 84 rotates and travels.

  The internal combustion engine 91 is a single-cylinder four-cycle internal combustion engine, and protrudes from the front surface of the unit case 91a with the cylinder block 91b, the cylinder head 91c, and the cylinder head cover 91d stacked in a posture that is largely inclined forward to a substantially horizontal state. Yes.

The main intake pipe 2 extends upward from the upper intake port of the forwardly inclined cylinder head 91c.
The intake pipe 2 has a downstream opening end coupled to the intake port opening of the cylinder head 91c, and curves upward while extending upward, and an upstream opening end is coupled to the throttle body 3.

  An air cleaner box 108 is suspended obliquely upward from the front of the throttle body 3, and is suspended from the main frame 73 via a bracket 109. The air cleaner box 108 and the throttle body 3 are connected by a connecting tube 107.

As described above, since the intake pipe 2 is attached to the cylinder head 91c tilted forward of the internal combustion engine 91, the cylindrical holding portion 10 branched from the intake pipe 2 protrudes obliquely upward and rearward.
Accordingly, the missing portion 15 of the cylindrical holding portion 10 faces the left side in the vehicle body width direction, and the electrical coupler Ic of the fuel injection valve I projects leftward from the missing portion 15.
The drain hole 15w is located at the lowest position of the cylindrical holding part 10 inclined rearward and upward, and the water that has entered the cylindrical holding part 10 can be discharged to the outside through the drain hole 15w.

The fuel introduction pipe 32 formed integrally with the joint cap 30 that covers the fuel injection valve I protrudes rearward.
A fuel tank 102 is mounted at the rear of the vehicle body, and a fuel pump 103 provided at the front of the fuel tank 102 and a fuel introduction pipe 32 protruding rearward of the joint cap 30 are connected by a fuel hose 104. .

The fuel hose 104 coupled at the rear end to the fuel pump 103 extends forward along the inner surface of the left seat rail 75 and further extends the left side surface of the rear half of the main frame 73 forward and covers the fuel injection valve I. A front end of the joint cap 30 is connected to a fuel introduction pipe 32 projecting rearward of the joint cap 30 via a connector 105.
Thus, the fuel introduction pipe 32 of the joint cap 30 is attached so as to face the fuel tank 102 on the rear side of the vehicle body, so that the fuel hose 104 can be shortened.

  Since the missing part 15 of the cylindrical holding part 10 is open in the lateral direction (left direction) of the vehicle body, the electrical coupler Ic is lateral to the vehicle body and does not interfere with the fuel hose 104 extending rearward of the vehicle body. The height of the part 10 can be suppressed, and as a result, the main frame 73 can be lowered, which contributes to the improvement of the straddling property.

In the above embodiment, the flange portions 31p, 31q are partially formed on the joint cap 30. However, another embodiment formed over the entire circumference is shown in FIGS. 18 and 19 and described. To do.
In the present embodiment, only the joint cap is different from the above embodiment, and therefore, other members are indicated by the same reference numerals as those in the above embodiment.

The cap 51 having a bottomed cylindrical shape, the lower engaging claws 51a and 51b, and the fuel introduction pipe 52 in the joint cap 50 have the same shape as the joint cap 30, but the flange 51f is formed on the cap 51. A disk part 51fa is formed on the entire upper part so as to extend beyond the outer peripheral edge of the upper cylindrical wall 13 of the cylindrical holding part 10, and the outer peripheral part of the disk part 51fa is bent downward. An annular portion 51fb is formed.
In addition, convex portions 51fc and 51fd are formed at predetermined positions on the lower surface of the disc portion 51fa in the same manner as the joint cap 30.

  Therefore, when the fuel injection valve I is inserted and attached to the cylindrical holding part 10 via the joint cap 50, the flange part 51f of the joint cap 50 covers the opening of the upper cylindrical wall 13 of the cylindrical holding part 10 over the entire surface. It is possible to prevent foreign matters such as water and sand from entering the cylindrical holder 10, and to more reliably block the operation sound of the fuel injection valve.

  In the above embodiment, the cylindrical holding portion 10 is integrally formed to protrude from the intake pipe 2, but the present invention may be such that the cylindrical holding portion protrudes integrally from the cylinder head.

1 is a perspective view of an intake pipe and its vicinity showing a fuel injection valve mounting structure according to an embodiment of the present invention. It is a perspective view of a cylindrical holding part formed integrally with an intake pipe. It is the same side view. FIG. 4 is a view as seen from an arrow IV in FIG. 3. It is the VV sectional view taken on the line of FIG. It is the VI-VI sectional view taken on the line of FIG. It is a VII arrow line view of FIG. It is the VIII-VIII sectional view taken on the line of FIG. It is the IX-IX sectional view taken on the line of FIG. It is the XX sectional view taken on the line of FIG. It is a disassembled perspective view, such as a cylinder holding part, a fuel injection valve, and a joint cap. It is a disassembled perspective view of a cylindrical holding | maintenance part, a small fuel injection valve, and a joint cap. It is a perspective view in the state where a small fuel injection valve and a joint cap were inserted in a cylindrical holding part. It is a perspective view of the state which completed the assembly | attachment of the fuel injection valve to the cylindrical holding part via the joint cap. It is the same side view. FIG. FIG. 3 is a side view of a motorcycle equipped with a power unit to which the fuel injection valve mounting structure is applied. It is a perspective view which shows the attachment structure of the fuel injection valve which concerns on another embodiment. FIG.

Explanation of symbols

E ... Internal combustion engine, I ... Fuel injection valve, Ib ... Main body, Ic ... Electrical component coupler,
DESCRIPTION OF SYMBOLS 1 ... Cylinder head, 2 ... Intake pipe, 3 ... Throttle body, 4 ... Metal collar, 5 ... Metal internal thread member,
DESCRIPTION OF SYMBOLS 10 ... Cylindrical holding part, 11 ... Lower cylindrical wall, 12 ... Center cylindrical wall, 13 ... Upper cylindrical wall, 13s ... Open end face, 15 ... Defect part, 15w ... Drain hole, 16 ... Vertical groove, 17 ... Horizontal groove, 17u ... upper surface, 18 ... transverse groove, 18u ... upper surface, 20, 21 ... spring member, 20a, 21a ... concave portion, 25 ... seal member, 26 ... O-ring,
30 ... Joint cap, 31 ... Cap part, 31a, 31b ... Engagement claw, 31p, 31q ... Flange part, 32 ... Fuel introduction pipe,
50 ... joint cap, 51a, 51b ... engaging claw, 51f ... flange, 52 ... fuel introduction pipe.

Claims (10)

A fuel injection side end portion of the fuel injection valve is fitted into a mounting hole formed at a predetermined position of an intake pipe or a cylinder head for leading intake air to the combustion chamber of the internal combustion engine, and the fuel introduction side end portion of the fuel injection valve is the same. In a fuel injection valve mounting structure that is held by a holding portion that is integrally formed on the intake pipe or the cylinder head via a joint cap that covers the end portion on the fuel introduction side.
The holding portion is a cylindrical holding portion formed in a cylindrical shape in which a cylindrical wall surrounds a side of a main body of the fuel injection valve,
A deficient portion that can be inserted into and protrude from the body of the fuel injection valve to a part of the cylindrical wall of the cylindrical holding portion is formed around the opening end surface of the cylindrical wall. A fuel injection valve mounting structure formed so as to be recessed in a direction of a generatrix of the surface. A plurality of engaging claws are formed in the radial direction on the outer periphery of the joint cap,
A plurality of lateral grooves for engaging the engaging claws are formed in the circumferential direction on the inner surface of the cylindrical wall of the cylindrical holding portion, and from the end of the horizontal groove to the opening end surface of the cylindrical wall. 2. The fuel injection valve mounting structure according to claim 1, wherein a plurality of vertical grooves are formed so as to face each other in the direction of the generatrix of the circumferential surface.   The fuel injection valve mounting structure according to claim 2, wherein the defective portion also serves as one of the longitudinal grooves.   The fuel injection valve mounting structure according to claim 3, wherein the lateral groove is formed so as to communicate with the defective portion.   The upper surface facing downward of the transverse groove forms a plane perpendicular to the generatrix of the peripheral surface of the cylindrical holding portion, and a part communicating with the defect portion is inclined obliquely upward toward the outside. 5. The fuel injection valve mounting structure according to claim 4, wherein the inclined surface is formed. The joint cap has a flange portion formed above the engaging claw,
When the joint cap is engaged and held by the cylindrical holding portion, an elastic member is interposed between the opening end surface of the cylindrical holding portion and the flange portion of the joint cap. 6. The fuel injection valve mounting structure according to claim 2, wherein the cap is biased upward with respect to the cylindrical holding portion.   A concave portion and a convex portion are respectively formed at predetermined portions of the elastic member and the flange portion of the joint cap that are locked to the locking portion of the opening end surface of the cylindrical holding portion. 7. The fuel injection valve mounting structure according to claim 6, wherein the joint cap is positioned and engaged and held with respect to the cylindrical holding portion by mutual fitting.   8. The fuel injection valve mounting structure according to claim 6, wherein the opening end surface of the cylindrical holding portion is entirely covered with the flange portion.   In a state where the joint cap is engaged and held by the cylindrical holding portion, a fuel introduction pipe protruding from the joint cap and connected to a fuel pipe is positioned above the opening end surface of the cylindrical holding portion. The fuel injection valve mounting structure according to any one of claims 1 to 8, wherein the fuel injection valve mounting structure is provided.   The cylindrical holding part is inclined while being attached to the intake pipe or the cylinder head, and a drain hole is formed at the lowest position of the inclined cylindrical holding part. The fuel injection valve mounting structure according to any one of claims 1 to 9.

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