JP2019085923A - engine - Google Patents

Abstract

To easily mount a fuel injection valve while securing positioning accuracy of the fuel injection valve.SOLUTION: An engine includes: an injector 30 having a fuel injection section 40 inserted into a cylinder head 21, a fuel introduction section 41 inserted into a fuel gallery 31, a valve body section 42 provided between the fuel injection section 40 and the fuel introduction section 41 and a connector section 43 extended outwards from the valve body section 42; and an injection valve holder 54 sandwiched between the fuel gallery 31 and the valve body section 42 and transmitting pressing force from the fuel gallery 31 to the injector 30. The injection valve holder 54 includes: a holder body 61 mounted to the valve body section 42 to constrain the connector section 43; and a positioning piece 62 extended from the holder body 61 toward one of the cylinder head 21 and the fuel gallery 31. A positioning groove 71 engaged with the positioning piece 62 is formed in one of the cylinder head 21 and the fuel gallery 31, and rigidity of the positioning piece 62 is lower than that of the holder body 61.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an engine provided with a fuel injection valve.

  The cylinder head of the engine is attached with a fuel injection valve that injects fuel into the combustion chamber and the intake port. As a mounting structure of the fuel injection valve, a structure in which a holder attached to the fuel injection valve is bolted and a structure in which the fuel injection valve is pressed by a fuel pipe are proposed (see Patent Documents 1 and 2).

Unexamined-Japanese-Patent No. 11-82241 gazette Japanese Patent Application Publication No. 2007-154679

  By the way, since the attachment structure described in patent documents 1 and 2 is a structure which combines a complicated part and attaches a fuel injection valve, the structure for attaching a fuel injection valve easily is called for. In addition, even in the case of simplifying the mounting structure of the fuel injection valve, the form of mixture of fuel and the state of fuel adhesion change, which affects the combustion, so that the positioning accuracy of the fuel injection valve with respect to the cylinder head is ensured. Is required.

  An object of the present invention is to simply attach a fuel injection valve while securing the positioning accuracy of the fuel injection valve.

  The engine according to the present invention is an engine provided with a cylinder head, and is attached to the cylinder head, and is inserted into the fuel gallery connected to the fuel pipe, a fuel injection unit inserted into the cylinder head, and the fuel gallery A fuel injection valve comprising: a fuel introduction portion; a valve main body portion provided between the fuel injection portion and the fuel introduction portion; and a connector portion extending outward from the valve main body portion; And an injection valve holder which is sandwiched between the valve body and transmits the pressing force from the fuel gallery to the fuel injection valve, and the injection valve holder is attached to the valve body and the connector And a positioning piece extending from the holder body toward one of the cylinder head and the fuel gallery. A positioning groove engaged with the positioning piece is formed in one of the fuel gallery and the fuel gallery, and the rigidity of the positioning piece against a force parallel to the center line of the fuel injection valve is the rigidity against the force parallel to the center line Lower than the rigidity of the holder body.

  According to the present invention, the injection valve holder includes the holder main body attached to the valve main body to restrain the connector, and the positioning piece extending from the holder main body toward one of the cylinder head and the fuel gallery. Further, a positioning groove engaged with the positioning piece is formed in one of the cylinder head and the fuel gallery. Thus, the fuel injection valve can be easily attached while securing the positioning accuracy of the fuel injection valve.

FIG. 1 is a schematic view showing an engine according to an embodiment of the present invention. It is a perspective view which shows a part of cylinder head from the arrow (alpha) direction of FIG. It is sectional drawing in alignment with the AA of FIG. It is an exploded view which shows the attachment process of the injector with respect to a cylinder head. It is a perspective view showing an example of an injection valve holder. (A) is a front view which shows an injection valve holder, (b) is a side view which shows an injection valve holder. It is the perspective view which showed the attachment hole of a cylinder head, and its vicinity. It is a perspective view which shows the positional relationship of a cylinder head and an injection valve holder. It is a top view which shows the positional relationship of a cylinder head, an injector, and an injection valve holder. (A) And (b) is an image figure which shows the front-end | tip shape of a positioning piece, and the cross-sectional shape of a positioning groove. (A) And (b) is sectional drawing which shows the attachment process of the injector in the engine which is other embodiment of this invention.

[Engine structure]
Hereinafter, embodiments of the present invention will be described in detail based on the drawings. FIG. 1 is a schematic view showing an engine 10 according to an embodiment of the present invention. As shown in FIG. 1, the engine 10 includes a cylinder block 11 provided in one cylinder bank, a cylinder block 12 provided in the other cylinder bank, and a crankshaft 13 supported by a pair of cylinder blocks 11 and 12 ,have. A piston 15 is accommodated in a cylinder bore 14 formed in each of the cylinder blocks 11 and 12, and a crankshaft 13 is connected to the piston 15 via a connecting rod 16.

  The cylinder heads 21 and 22 provided with the valve mechanism 20 are assembled to the respective cylinder blocks 11 and 12. Further, an intake port 24 communicating with the combustion chamber 23 is formed in each of the cylinder heads 21 and 22, and an intake valve 25 for opening and closing the intake port 24 is assembled. Further, an exhaust port 26 communicating with the combustion chamber 23 is formed in each of the cylinder heads 21 and 22, and an exhaust valve 27 for opening and closing the exhaust port 26 is assembled. An intake manifold (not shown) is connected to the intake port 24, and an exhaust manifold (not shown) is connected to the exhaust port 26.

  Further, an injector (fuel injection valve) 30 for injecting fuel to the combustion chamber 23 is attached to each of the cylinder heads 21 and 22. A fuel gallery 31 is connected to the injector 30, and a high pressure pump 33 is connected to the fuel gallery 31 via a fuel pipe 32. Thus, the fuel discharged from the high pressure pump 33 is supplied from the fuel pipe 32 to the fuel galleries 31 and distributed from the fuel gallery 31 to the injectors 30 of the cylinders. A low pressure pump (not shown) and a fuel tank are connected to the high pressure pump 33. The fuel gallery 31 for supplying fuel to the injectors 30 is also called a common rail, a delivery pipe or the like.

[Injector mounting structure]
FIG. 2 is a perspective view showing a part of the cylinder head 21 from the direction of arrow α in FIG. FIG. 3 is a cross-sectional view taken along the line AA of FIG. FIG. 4 is an exploded view showing the process of attaching the injector 30 to the cylinder head 21. As shown in FIG. In addition, the site | part similar to the site | part shown in FIG. 3 is shown by FIG. In the following description, although one cylinder head 21 is described, the other cylinder head 22 has the same structure as that of the cylinder head 21 and thus the description thereof is omitted.

  First, as shown in FIG. 4, the injector 30 having a stepped cylindrical shape has at one end the fuel injection portion 40 in which the injection hole 40a is formed, and the other fuel introduction portion 41 in which the introduction hole 41a is formed. Have at the end. Further, between the fuel injection portion 40 and the fuel introduction portion 41, there is provided a valve main portion 42 comprising a small diameter portion 42a and a large diameter portion 42b having a larger diameter than this. A solenoid for driving a needle valve (not shown) is incorporated in the valve body 42 of the injector 30. Further, the injector 30 is provided with a connector portion 43 for energizing a solenoid (not shown), and the connector portion 43 is formed so as to extend outward from the outer peripheral surface of the valve main body 42, that is, radially outward.

  As shown in FIGS. 3 and 4, the cylinder head 21 is formed with a mounting hole 50 communicating with the combustion chamber 23, and the fuel injection portion 40 of the injector 30 is inserted into the mounting hole 50. Further, a supply hole 51 communicating with the internal flow passage is formed in the fuel gallery 31, and the fuel introduction portion 41 of the injector 30 is inserted into the supply hole 51. As described above, the injector 30 is provided with the fuel injection unit 40 inserted into the cylinder head 21 and the fuel introduction unit 41 inserted into the fuel gallery 31. The fuel injection portion 40 is provided with a seal member 52 for preventing fuel leakage, and the fuel introduction portion 41 is provided with a seal member 53 for preventing fuel leakage.

  As shown by the white arrow in FIG. 4, when attaching the injector 30 to the cylinder head 21, the fuel injection portion 40 of the injector 30 is inserted into the mounting hole 50 of the cylinder head 21. Further, after the injection valve holder 54 is attached to the valve main body 42 of the injector 30, the fuel gallery 31 is attached to the fuel introduction part 41 of the injector 30. That is, the fuel introduction portion 41 of the injector 30 is inserted into the supply hole 51 of the fuel gallery 31. Then, as shown in FIG. 2, the mounting bosses 55 formed on the fuel gallery 31 and the mounting bosses 56 of the cylinder head 21 butted against the fuel gallery 31 are mutually fastened using the bolt members 57.

  As described above, by attaching the fuel gallery 31 to the cylinder head 21, the injection valve holder 54 is sandwiched and compressed between the fuel gallery 31 and the large diameter portion 42 b of the valve main body 42. As a result, the pressing force is transmitted from the fuel gallery 31 to the injector 30 through the injection valve holder 54. As will be described later, since the injection valve holder 54 is deformed by compression, the injector 30 can be held with an appropriate pressing force by the injection valve holder 54 even if dimensional variations occur in the respective parts. .

[Injection valve holder structure]
FIG. 5 is a perspective view showing an example of the injection valve holder 54. As shown in FIG. 6 (a) is a front view showing the injection valve holder 54, and FIG. 6 (b) is a side view showing the injection valve holder 54. As shown in FIG.

  As shown in FIGS. 5 and 6, the injection valve holder 54, which is a sheet metal part, has a substantially cylindrical holder main body 61 provided with an opening 60 in which a part of the outer periphery is notched, and positioning extending downward from the holder main body 61 And a piece 62. Further, the holder main body 61 of the injection valve holder 54 includes a first arc portion (first end) 63 curved in an arc shape and a second arc portion (second end) 64 curved in an arc shape. ing. That is, as shown in FIG. 3, the holder main body 61 includes the first arc portion 63 in contact with the fuel gallery 31 and the second arc portion 64 in contact with the large diameter portion 42 b of the valve main portion 42. . Further, as shown in FIGS. 5 and 6, the holder main body 61 is provided with four holder deformation portions (first deformation portions) 65 which connect the first arc portion 63 and the second arc portion 64 to each other. The holder deformation portion 65 protrudes outward and is bent in a hairpin shape, and the four holder deformation portions 65 are installed at substantially equal intervals in the circumferential direction of the holder main body 61.

  As shown in FIG. 5 and FIG. 6, the positioning piece 62 of the injection valve holder 54 is a positioning for connecting the substantially V-shaped tapered tip portion 66, the second arc portion 64 and the tip portion 66 to each other. And a deformation portion (second deformation portion) 67. The positioning deformation portion 67 protrudes outward and is bent into a hairpin shape. The rigidity of the positioning deformation portion 67 is set to be lower than the rigidity of the holder deformation portion 65 described above. That is, the rigidity of the positioning piece 62 for the force parallel to the center line Ca of the injector 30 is set to be lower than the rigidity of the holder main body 61 for the force parallel to the center line Ca. Further, as shown by an arrow X in FIG. 6B, the tip end portion 66 of the positioning piece 62 is disposed outside the outer peripheral surface 61a of the holder main body 61, that is, radially outward. That is, the tip end portion 66 of the positioning piece 62 is offset to the outer side than the outer peripheral surface 61 a of the holder main body 61.

[Positioning structure]
FIG. 7 is a perspective view showing the mounting hole 50 of the cylinder head 21 and the vicinity thereof. FIG. 8 is a perspective view showing the positional relationship between the cylinder head 21 and the injection valve holder 54. As shown in FIG. FIG. 9 is a plan view showing the positional relationship between the cylinder head 21, the injector 30 and the injection valve holder 54.

  As shown in FIG. 7, an annular wall 70 is formed in the cylinder head 21 so as to surround the mounting hole 50, and a substantially V-shaped positioning groove 71 is formed in the annular wall 70. . As shown in FIG. 8, the positioning piece 62 of the injection valve holder 54 mounted on the injector 30 is engaged with the positioning groove 71 of the cylinder head 21. In this manner, by engaging the positioning piece 62 with the positioning groove 71, the injection valve holder 54 can be positioned relative to the cylinder head 21 and the injector 30 can be positioned relative to the cylinder head 21.

  As shown in FIG. 9, a holder main body 61 of the injection valve holder 54 is attached to the valve main body 42 of the injector 30. Further, the connector portion 43 of the injector 30 is sandwiched in the opening 60 of the holder main body 61. Thus, since the injector 30 and the injection valve holder 54 are mutually restrained, the injector 30 can be positioned with respect to the cylinder head 21 by positioning the injection valve holder 54 and the cylinder head 21 to each other. That is, by engaging the positioning piece 62 with the positioning groove 71, the injector 30 is positioned in the rotational direction about the center line Ca. Thus, the positioning accuracy of the injector 30 for injecting the fuel into the combustion chamber 23 can be enhanced, and the fuel can be appropriately injected into the combustion chamber 23. Therefore, the mixture can be combusted well in the combustion chamber 23. be able to.

  As described above, since the positioning piece 62 is provided on the injection valve holder 54, the injector 30 can be easily positioned on the cylinder head 21 simply by attaching the injection valve holder 54 to the injector 30. Moreover, as described above, the rigidity of the positioning piece 62 for the force parallel to the center line Ca of the injector 30 is set lower than the rigidity of the holder main body 61 for the force parallel to the center line Ca. Thereby, when the fuel gallery 31 is tightened to the cylinder head 21, even if the positioning piece 62 is deformed by being pushed into the fuel gallery 31, no large repulsive force is generated from the positioning piece 62, The holder main body 61 can be appropriately deformed along with the pressing of the fuel gallery 31. That is, when the fuel gallery 31 is tightened to the cylinder head 21, the holder deformation portion 65 of the injection valve holder 54 can be appropriately deformed, and the injector 30 can be held with an appropriate pressing force.

  Further, as shown in FIG. 6B, the tip end portion 66 of the positioning piece 62 is disposed outside the outer peripheral surface 61 a of the holder main body 61. Thereby, when the fuel gallery 31 is tightened to the cylinder head 21, even when the positioning piece 62 is deformed by being pushed into the fuel gallery 31, the repulsive force from the positioning piece 62 is applied to the second arc portion 64. The holder main body 61 can be appropriately deformed along with the pressing of the fuel gallery 31 without directly acting on it. That is, when the positioning piece 62 and the second arc portion 64 are disposed on a straight line, the repulsive force from the positioning piece 62 is easily transmitted to the holder deformation portion 65, but this can be eliminated. The holder deformation portion 65 can be deformed appropriately. Thus, when the fuel gallery 31 is tightened to the cylinder head 21, the holder deformation portion 65 of the injection valve holder 54 can be appropriately deformed, and the injector 30 can be held with an appropriate pressing force.

  FIGS. 10A and 10B are image diagrams showing the tip shape of the positioning piece 62 and the cross-sectional shape of the positioning groove 71. FIG. As shown in FIG. 10A, the radius of curvature R1 at the tip end 72 of the positioning piece 62 is larger than the radius of curvature R2 at the bottom 73 of the positioning groove 71. Thus, as shown in FIG. 10B, a gap G is provided between the tip end 72 of the positioning piece 62 and the bottom 73 of the positioning groove 71 opposed thereto. By thus providing the gap G between the positioning piece 62 and the positioning groove 71, the inclined surface 62a of the positioning piece 62 and the inclined surface 71a of the positioning groove 71 can be brought into contact with each other. Thereby, the center Cb1 of the positioning piece 62 and the center Cb2 of the positioning groove 71 can be made to coincide with each other, and the positioning accuracy of the injection valve holder 54, that is, the injector 30 with respect to the cylinder head 21 can be improved. Since the positioning piece 62 is guided along the inclined surface 71a when inserting the positioning piece 62 into the positioning groove 71, the center Cb1 of the positioning piece 62 and the positioning groove 71 without visual observation by the operator. , Cb2 can be matched.

[Other embodiments]
Although the positioning groove 71 is formed in the cylinder head 21 in the above description, the invention is not limited thereto. The positioning groove 80 may be formed on the fuel gallery 31. FIGS. 11A and 11B are cross-sectional views showing the process of mounting the injector 30 in an engine according to another embodiment of the present invention. In addition, in FIG. 11, about the member and site | part similar to the member and site | part which were shown in FIG. 3, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 11A, in the vicinity of the supply hole 51 of the fuel gallery 31, a substantially V-shaped positioning groove 80 is formed. The injection valve holder 54 is attached to the valve main body 42 of the injector 30 with the positioning piece 62 directed to the fuel gallery 31 side. As a result, as shown in FIG. 11B, the positioning piece 62 of the injection valve holder 54 is engaged with the positioning groove 80 of the fuel gallery 31. As described above, since the injection valve holder 54 is positioned with respect to the fuel gallery 31, the injector 30 can be positioned with respect to the cylinder head 21.

  It is needless to say that the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention. Although the present invention is applied to the horizontally opposed engine 10 in the above description, the present invention is not limited to this, and may be applied to a series engine, a V-type engine, or the like. Further, although the injector 30 for injecting the fuel into the combustion chamber 23 is adopted in the above description, the invention is not limited to this, and an injector for injecting the fuel to the intake port 24 may be adopted.

  In the illustrated example, the positioning piece 62 is extended in parallel with the center line Ca of the holder main body 61, but the invention is not limited thereto. The positioning piece 62 may be inclined with respect to the center line Ca. Further, in the illustrated example, the holder deformation portion 65 and the positioning deformation portion 67 are bent into a hairpin shape, but the present invention is not limited to this, and holder deformation portions and positioning deformation portions of other shapes may be adopted. . Further, although two injectors 30 are connected to one fuel gallery 31 in the illustrated example, the invention is not limited thereto, and one injector 30 may be connected to one fuel gallery 31. Three or more injectors 30 may be connected to one fuel gallery 31.

DESCRIPTION OF SYMBOLS 10 engines 21 and 22 cylinder head 23 combustion chamber 30 injector (fuel injection valve)
31 fuel gallery 32 fuel piping 40 fuel injection portion 41 fuel introduction portion 42 valve main portion 43 connector portion 54 injection valve holder 61 holder main body 61 a outer peripheral surface 62 positioning piece 63 first arc portion (first end portion)
64 Second arc (second end)
65 Holder deformation part (1st deformation part)
66 Tip portion 67 Positioning deformation portion (second deformation portion)
71 Positioning groove 72 Tip 73 Bottom 80 Positioning groove G Clearance

Claims (7)

An engine comprising a cylinder head,
A fuel gallery attached to the cylinder head and connected to fuel piping;
A fuel injection portion inserted into the cylinder head, a fuel introduction portion inserted into the fuel gallery, a valve main portion provided between the fuel injection portion and the fuel introduction portion, and an outer side from the valve main portion A connector portion extending to the
An injection valve holder which is sandwiched between the fuel gallery and the valve main body and transmits a pressing force from the fuel gallery to the fuel injection valve;
Have
The injection valve holder includes a holder main body attached to the valve main body to restrain the connector, and a positioning piece extending from the holder main body toward one of the cylinder head and the fuel gallery.
A positioning groove engaged with the positioning piece is formed in one of the cylinder head and the fuel gallery.
The rigidity of the positioning piece for a force parallel to the center line of the fuel injection valve is lower than the rigidity of the holder body for a force parallel to the center line.
engine. In the engine according to claim 1,
The positioning piece is disposed outside the outer circumferential surface of the holder body.
engine. In the engine according to claim 1 or 2,
The holder body has a first end in contact with the fuel gallery, a second end in contact with the valve body, and a first deformation provided between the first end and the second end. With the department,
The positioning piece includes a tip portion engaged with the positioning groove, and a second deformation portion provided between one of the first end and the second end and the tip portion.
The rigidity of the second deformation portion to a force parallel to the center line of the fuel injection valve is lower than the rigidity of the first deformation portion to a force parallel to the center line.
engine. In the engine according to any one of claims 1 to 3,
By engaging the positioning piece with the positioning groove, the fuel injection valve is positioned in a rotational direction about the center line.
engine. In the engine according to any one of claims 1 to 4,
The fuel injection unit injects fuel into a combustion chamber of the cylinder head.
engine. In the engine according to any one of claims 1 to 5,
A gap is provided between the tip of the positioning piece and the bottom of the positioning groove opposite thereto.
engine. In the engine according to any one of claims 1 to 6,
The positioning groove is formed in the cylinder head.
engine.

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