JP2010185323A - Mounting structure for fuel injection valve and washer of fuel injection valve used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mounting structure for a fuel injection valve capable of improving the airtightness at the mounting hole while tolerating displacement of the axis of a mounting hole and the axis of the fuel injection valve at the mounting of a fuel injection valve to an engine. <P>SOLUTION: An engine 10 has a mounting hole 20 for mounting a fuel injection valve 30. A seat 24 is formed on the mounting hole 20. A level difference part 36 is formed in the fuel injection valve 30 facing the seat 24. A washer 40 is disposed between the seat 24 and the level difference part 36. The washer 40 has an upper contact part 42 contacted with the level difference part 36, and a lower contact part 43 contacted with the seat 24. An upper contact structure 50 is formed with the upper contact part 42 and the level difference part 36, and a lower contact structure 51 is formed with the lower contact part 43 and the seat 24. The upper contact structure 50 has an axis displacement absorbing structure comprising a spherical surface 36 and a conical surface 42. The lower contact structure 51 has an airtight structure comprising a projection part 43 and a flat surface 24. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a structure for mounting a fuel injection valve to an internal combustion engine (hereinafter simply referred to as an engine), and a washer for the fuel injection valve used for mounting the fuel injection valve.

  There is known a structure in which a fuel injection valve having an injection portion for injecting fuel at an end portion is attached to a mounting hole formed in an engine (see Patent Documents 1 to 3). The mounting structure described in Patent Document 1 has a structure in which a washer that supports the fuel injection valve is disposed between a seat portion of a mounting hole formed in the engine and a step portion formed in the fuel injection valve. Yes.

  In this structure, the washer is formed with a conical surface composed of a surface inclined toward the center of the washer, and the stepped portion of the fuel injection valve has a conical surface formed on the washer and is in contact with the conical surface over the entire circumference. A spherical surface made up of parts is formed.

  According to this structure, even if the axis of the fuel injection valve is inclined with respect to the axis of the attachment hole and the fuel injection valve is attached to the attachment hole, the above-described difference between the washer and the step portion of the fuel injection valve is as described above. The contact state can be maintained.

Japanese Patent No. 4034662

  Here, in the case of a so-called direct injection engine in which fuel is directly injected into the combustion chamber of the engine, there is a possibility that the combustion gas generated in the combustion chamber flows into the gap between the mounting hole and the fuel injection valve and leaks outside the engine. For this reason, it is necessary to further improve the sealing function between the mounting hole and the fuel injection valve.

  However, the washer in the technique described in Patent Document 1 has a function of maintaining the contact state between the washer and the stepped portion of the fuel injection valve even if the axis of the fuel injection valve and the mounting hole is displaced. However, the sealing performance is not sufficient.

  This is because, in the structure described in Patent Document 1, a portion of the washer that contacts the seat portion and the seat portion are flat, and the portion and the seat portion are in surface contact.

  For this reason, a contact pressure becomes scarce and the sealing performance between the said site | part and a seat part is low. Here, the contact pressure refers to the pressure per unit area at the contact portion. If the load acting on the contact portion is the same, the higher the contact pressure, the higher the sealing performance.

  The present invention has been made in view of the above-described problems, and its object is to allow a deviation between the axis of the mounting hole and the axis of the fuel injection valve when the fuel injection valve is attached to the internal combustion engine. It is another object of the present invention to provide a fuel injection valve mounting structure capable of improving the airtightness of the mounting hole.

  Another object of the present invention is to provide a fuel injection valve that can improve the airtightness in the mounting hole while allowing a shift between the shaft center of the mounting hole and the shaft center of the fuel injection valve when the fuel injection valve is attached to the internal combustion engine. To provide a washer.

The invention according to claim 1 is a fuel injection valve mounting structure in which a fuel injection valve having an injection portion for injecting fuel at an end is attached to a mounting hole formed in an internal combustion engine.
An annular seat portion that receives a load from the fuel injection valve in a state where the fuel injection valve is attached to the internal combustion engine is formed in the mounting hole, and an annular step portion that faces the seat portion in the insertion direction is formed on the fuel injection valve. An annular washer that supports the fuel injection valve having a first contact portion that contacts the step portion and a second contact portion that contacts the seat portion is disposed between the seat portion and the step portion. And
A first contact structure is formed by contacting the first contact portion and the stepped portion, and a second contact structure is formed by contacting the second contact portion and the seat portion,
The first contact structure is an axis misalignment absorbing structure capable of maintaining the contact state between the washer and the stepped portion of the fuel injection valve even when the axis of the fuel injection valve is deviated from the axis of the mounting hole. The second contact structure is a close contact structure in which the washer and the seat of the mounting hole are in close contact with each other.
The shaft misalignment absorbing structure is constituted by a conical surface formed by a surface inclined toward the shaft center of the washer or the fuel injection valve, and a spherical surface formed by a part of the surface of a sphere that contacts the conical surface over the entire circumference, The close contact structure is characterized by an annular protrusion and a receiving part that receives and contacts the protrusion.

The invention according to claim 2 is a fuel injection valve mounting structure in which a fuel injection valve having an injection portion for injecting fuel at an end portion is attached to a mounting hole formed in the internal combustion engine,
An annular seat portion that receives a load from the fuel injection valve in a state where the fuel injection valve is attached to the internal combustion engine is formed in the mounting hole, and an annular step portion that faces the seat portion in the insertion direction is formed on the fuel injection valve. An annular washer that supports the fuel injection valve having a first contact portion that contacts the step portion and a second contact portion that contacts the seat portion is disposed between the seat portion and the step portion. And
A first contact structure is formed by contact between the first contact portion and the stepped portion, and a second contact structure is formed by contact between the second contact portion and the seat portion,
The first contact structure is a close-contact structure in which the washer and the step portion of the fuel injection valve are in close contact with each other, and the second contact structure is not even when the axis of the fuel injection valve is displaced from the axis of the mounting hole. It has a misalignment absorbing structure that can maintain the contact state with the stepped portion of the injection valve,
The shaft misalignment absorbing structure is composed of a conical surface composed of a surface inclined toward the shaft center of the washer or the mounting hole, and a spherical surface composed of a part of the surface of a sphere contacting the conical surface over the entire circumference. However, it is characterized by comprising an annular projecting portion and a receiving portion that receives and contacts the projecting portion.

The invention according to claim 9 is formed in the internal combustion engine, and includes an attachment hole having an annular seat portion on the inner wall, an injection portion for injecting fuel at the end portion, and an annular portion facing the seat portion in the insertion direction on the side wall. In the washer of the fuel injection valve disposed between the fuel injection valve having the stepped portion and supporting the fuel injection valve,
An annularly formed main body part, a first contact part formed on the step part side of the main body part and forming a first contact structure by contacting the step part, and a seat part side of the main body part, A second contact portion that forms a second contact structure by contacting the portion,
The first contact structure is an axis misalignment absorbing structure capable of maintaining the contact state between the washer and the stepped portion of the fuel injection valve even when the axis of the fuel injection valve is deviated from the axis of the mounting hole. The second contact structure is a close contact structure in which the washer and the seat of the mounting hole are in close contact with each other.
The shaft misalignment absorbing structure is constituted by a conical surface formed by a surface inclined toward the shaft center of the washer or the fuel injection valve, and a spherical surface formed by a part of the surface of a sphere that contacts the conical surface over the entire circumference, The close-contact structure is composed of an annular projection and a receiving portion that receives and contacts the projection,
Either the conical surface or the spherical surface is formed on the first contact portion, and any one of the annular protrusion and the receiving portion is formed on the second contact portion.

Further, the invention according to claim 10 is formed in the internal combustion engine, and has a mounting hole having a seat portion on the inner wall, an injection portion for injecting fuel at the end portion, and a step portion facing the seat portion in the insertion direction on the side wall. In the washer of the fuel injection valve that is disposed between and supports the fuel injection valve,
An annularly formed main body part, a first contact part formed on the step part side of the main body part and forming a first contact structure by contacting the step part, and a seat part side of the main body part, A second contact portion that forms a second contact structure by contacting the portion,
The first contact structure is a close-contact structure in which the washer and the step portion of the fuel injection valve are in close contact with each other, and the second contact structure is not even when the axis of the fuel injection valve is displaced from the axis of the mounting hole. It has a misalignment absorbing structure that can maintain the contact state with the stepped portion of the injection valve,
The shaft misalignment absorbing structure is composed of a conical surface composed of a surface inclined toward the shaft center of the washer or the mounting hole, and a spherical surface composed of a part of the surface of a sphere contacting the conical surface over the entire circumference. Is composed of an annular projection and a receiving portion that receives and contacts the projection,
Either the annular protrusion or the receiving portion is formed on the first contact portion, and either the conical surface or the spherical surface is formed on the second contact portion.

  According to these inventions, the washer is disposed between the seat portion of the mounting hole and the step portion of the fuel injection valve. The first contact structure composed of a stepped portion that contacts the first contact portion of the washer is either an axis misalignment absorbing structure composed of a conical surface and a spherical surface, or a close contact structure composed of a projection and a receiving portion. It has become. Thereby, a 2nd contact structure turns into a structure different from the structure which a 1st contact structure takes among the said structures.

  According to the present invention, the conical surface is a surface inclined toward the axial center of the washer, the fuel injection valve or the mounting hole, and the spherical surface is a part of the surface of the sphere that contacts the conical surface over the entire circumference. It has become. The projecting portion is formed in an annular shape, and the receiving portion is formed so as to receive and contact the projecting portion formed in an annular shape.

  For example, when the first contact structure is an off-axis absorbing structure and the second contact structure is a close-contact structure, the first contact portion and the stepped portion of the washer in the first contact structure are configured by a conical surface and a spherical surface, The second contact portion and the seat portion of the washer in the second contact structure are constituted by the projection portion and the receiving portion.

  In this case, even if the fuel injection valve is inserted into the mounting hole in an inclined manner, the spherical cross section of the first contact structure is always circular, so that it always contacts the conical surface.

  For this reason, in the first contact structure, even if the shaft center of the fuel injection valve and the shaft center of the mounting hole are displaced, the close contact between the washer and the fuel injection valve can be maintained, and the fuel injection valve and the mounting hole Axis deviation can be allowed.

  According to this structure, since the contact between the spherical surface and the conical surface is a line contact, a relatively high contact pressure can be obtained, and the sealing performance can be improved.

  Moreover, since the 2nd contact structure is comprised by the cyclic | annular protrusion part and the receiving part which receives it, a contact pressure becomes higher than the conventional structure. Therefore, also in this structure, the sealing performance can be improved.

  According to the above-described configuration, it is possible to improve the sealing performance of the washer and the fuel injection valve, and the washer and the attachment hole, while allowing the axial deviation between the fuel injection valve and the attachment hole.

  In addition, even when the first contact structure is a close contact structure and the second contact structure is an axis deviation absorbing structure, the same operational effects as described above can be obtained, and the washer and the fuel injection valve, and the washer and the mounting hole can be obtained. Each sealing performance can be improved.

  Therefore, according to these inventions, the fuel injection valve mounting structure capable of improving the airtightness in the mounting hole while allowing the axial displacement between the fuel injection valve and the mounting hole, and the fuel injection valve used in this mounting structure. A washer can be provided.

  In the first, second, ninth and tenth aspects of the present invention, the shape formed on the first contact portion and the second contact portion of the washer is not particularly specified. Generally, when forming the surface of an article into a predetermined shape, a conical surface is easier to process than a spherical surface as described in the claims. Moreover, since the surface shape of an engine or a fuel injection valve is complicated, a desired shape cannot be obtained only by casting or forging. Therefore, in practice, after a rough shape is formed by casting or forging, a desired shape is obtained by performing a removal process or the like.

  On the other hand, the washer, which is a part having a smaller physique than the engine and the fuel injection valve as described in the claims, is relatively simple in structure as compared with the engine and the fuel injection valve. A shape is obtained. According to the press processing, since a processing is performed using a mold formed in a predetermined shape, a desired shape can be easily obtained.

  On the other hand, the invention according to claim 3 or 11 is characterized in that, when the first contact structure is an off-axis absorbing structure and the second contact structure is a close contact structure, the first contact portion is a spherical surface. Yes. The invention according to claim 4 or 12 is characterized in that when the first contact structure is an off-axis absorbing structure and the second contact structure is a close-contact structure, the second contact part is an annular protrusion. It is said. Further, the invention according to claim 5 or 13 is characterized in that, when the first contact structure is a close contact structure and the second contact structure is an axis deviation absorbing structure, the second contact portion is a spherical surface. The invention described in claim 6 or 14 is characterized in that, when the first contact structure is a close contact structure and the second contact structure is an axis deviation absorbing structure, the first contact portion is the annular protrusion. It is said.

  According to these inventions, the curved surface and the protruding portion having a relatively complicated shape are formed on the washer that is smaller in size than the engine and the fuel injection valve and can be created relatively easily. In addition, the overall manufacturing cost of the washer and the like can be suppressed.

  The invention according to claim 7 is characterized in that an annular seal member for filling a gap between the mounting hole and the fuel injection valve is attached to the injection portion.

  According to this invention, since the annular seal member that fills the gap between the mounting hole and the fuel injection valve is attached to the injection portion, the airtightness can be further improved.

  According to the eighth aspect of the present invention, the end of the mounting hole on the insertion direction side opens into a combustion chamber provided in the internal combustion engine, and the injection unit is disposed in the mounting hole so that fuel can be directly injected into the combustion chamber. It is characterized by having.

  According to the present invention, the structure according to any one of claims 1 to 7 is suitable for use in a direct-injection engine that further needs to ensure airtightness.

It is sectional drawing which shows the direct injection type gasoline engine to which the attachment structure of the fuel injection valve by 1st Embodiment of this invention is applied. It is sectional drawing which shows the principal part of the direct injection type gasoline engine to which the attachment structure of the fuel injection valve by 1st Embodiment of this invention is applied. FIG. 3 is a cross-sectional view showing a state where the fuel injection valve shown in FIG. 2 is attached to the attachment hole while the axis S1 of the fuel injection valve is displaced from the axis S2 of the attachment hole. It is sectional drawing which shows the principal part of the direct injection type engine to which the attachment structure of the fuel injection valve by 2nd Embodiment is applied. It is sectional drawing which shows the principal part of the direct injection type engine to which the attachment structure of the fuel injection valve by 3rd Embodiment is applied. It is sectional drawing which shows the principal part of the direct injection type engine to which the attachment structure of the fuel injection valve by 4th Embodiment is applied. It is sectional drawing which shows the principal part of the direct injection type engine to which the fuel injection valve attachment structure by 5th Embodiment is applied.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In addition, the overlapping description is abbreviate | omitted by attaching | subjecting the same code | symbol to the component corresponding in each embodiment.

(First embodiment)
(Basic configuration)
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the drawings. FIG. 1 shows a direct injection gasoline engine to which a fuel injection valve mounting structure according to a first embodiment of the present invention is applied. FIG. 2 shows a main part of FIG.

  The engine 10 includes a cylinder block 11 and a cylinder head 12. The cylinder block 11 and the cylinder head 12 are formed by casting from, for example, iron or aluminum alloy. As shown in FIG. 1, the cylinder head 12 is disposed at the upper end portion of the cylinder block 11.

  A cylindrical cylinder 13 is formed in the cylinder block 11. The cylinder 13 opens at the upper end of the cylinder block 11. The cylinder 13 supports the piston 14 so as to be able to reciprocate. A combustion chamber 15 is formed on the inner wall of the cylinder 13 that supports the piston 14, the end surface of the piston 14 on the cylinder head 12 side, and the end surface of the cylinder head 12 on the piston 14 side.

  An intake passage 16 and an exhaust passage 17 are formed in the cylinder head 12. The intake passage 16 and the exhaust passage 17 are formed so as to be separated from each other as the distance from the combustion chamber 15 increases. The intake passage 16 and the exhaust passage 17 are each connected to the combustion chamber 15. The end of the intake passage 16 on the combustion chamber 15 side is opened and closed by an intake valve 18. The end of the exhaust passage 17 on the combustion chamber 15 side is opened and closed by an exhaust valve 19.

  A mounting hole 20 is formed between the intake passage 16 and the exhaust passage 17 of the cylinder head 12 and penetrates in the thickness direction of the cylinder head 12. The fuel injection valve 30 is fixed to the engine 10 by inserting the fuel injection valve 30 into the attachment hole 20. Hereinafter, the direction of insertion of the fuel injection valve 30 into the mounting hole 20 when the fuel injection valve 30 is fixed to the engine 10 is defined as the direction of insertion of the fuel injection valve 30. The end of the mounting hole 20 in the insertion direction, that is, the end of the cylinder block 11 is open to the combustion chamber 15.

  As shown in FIG. 2, the mounting hole 20 has a large diameter portion 21, a medium diameter portion 22, and a small diameter portion 23 having different inner diameters. The small diameter portion 23, the medium diameter portion 22 and the large diameter portion 21 are arranged in this order from the combustion chamber 15 side in the axial direction. The inner diameter of the medium diameter portion 22 is smaller than the inner diameter of the large diameter portion 21 and larger than the inner diameter of the small diameter portion 23. A seat portion 24 is formed between the large diameter portion 21 and the medium diameter portion 22 so as to face the direction opposite to the insertion direction of the fuel injection valve 30, and the seat portion 24 is interposed between the medium diameter portion 22 and the small diameter portion 23. Similarly, an inclined portion 25 is formed that faces in the direction opposite to the insertion direction of the fuel injection valve 30.

  Here, the seat portion 24 forms an annular flat surface 24 that runs along a direction substantially perpendicular to the axis S2 of the mounting hole 20 and circulates around the axis S2.

  Here, FIG. 2 shows a state in which the fuel injection valve 30 is attached to the attachment hole 20. In FIG. 2, S1 indicated by a long broken line indicates the axis of the fuel injection valve 30, and S2 indicated by a two-dot broken line indicates attachment. S3 which shows the axial center of the hole 20, and shows with a dashed-dotted line has shown the axial center of the washer 40 formed cyclically | annularly mentioned later.

  FIG. 2 shows a state in which these axial centers S1 to S3 overlap each other. In FIG. 2, the axial centers S <b> 1 to S <b> 3 are described so as to be shifted in a direction orthogonal to the axial center in order to facilitate explanation.

  In order to make the flat surface 24 contact with a washer 40, which will be described later, in an annular manner, the surface needs to have a desired flatness. In the present embodiment, the flat surface 24 of the cylinder head 12 is formed by forming a rough shape by casting and then performing removal processing such as cutting or grinding.

  The fuel injection valve 30 directly injects fuel toward the combustion chamber 15. The fuel injection valve 30 includes an injection part 31, a main body part 32, a connector part 34, a fuel introduction part 35, and the like. The injection unit 31 is disposed in the mounting hole 20 so that fuel can be directly injected into the combustion chamber 15. The injection part 31 is formed closer to the combustion chamber 15 than the main body part 32. The injection part 31 is comprised from the injection hole, the valve body etc. which are accommodated in the inside and open and close an injection hole.

  An annular seal member 60 that fills a gap formed between the injection portion 31 and the small diameter portion 23 is attached to the injection portion 31. As a result, leakage of mixed gas or combustion gas from the combustion chamber 15 to the outside of the cylinder head 12 through the attachment hole 20 is suppressed. For example, the seal member 60 is formed of Teflon (registered trademark).

  The outer diameter of the injection part 31 is smaller than the outer diameter of the main body part 32. Further, the injection unit 31 is smaller than the inner diameter of the medium diameter part 22. A part of the jet part 31 and the main body part 32 is inserted into the mounting hole 20. The outer diameters of a part of the injection part 31 and the main body part 32 inserted into the attachment hole 20 are such that the axis S1 of the fuel injection valve 30 is in the attachment hole 20 in a state where the fuel injection valve 30 is inserted into the attachment hole 20. The diameter is such that a part of the injection part 31 and the main body part 32 does not contact the inner walls of the small diameter part 23, the medium diameter part 22, and the large diameter part 21 even if they are inserted offset from the axis S 2.

  Since the jet part 31 and the main body part 32 have different outer diameters, a step part 36 is formed between these elements 31 and 32. The step portion 36 is formed in an annular shape. In the present embodiment, the stepped portion 36 forms a spherical surface 36 made of a part of the surface (broken line) of a sphere having a radius R1 centered on the axis S1 of the fuel injection valve 30. The spherical surface 36 faces the flat surface 24 in a state where the fuel injection valve 30 is inserted into the mounting hole 20.

  FIG. 3 shows a state in which the fuel injection valve 30 is attached to the attachment hole 20 while the axis S1 of the fuel injection valve 30 is displaced from the axis S2 of the attachment hole 20. In the present embodiment, the axis S1 is inclined with respect to the axis S2 by an angle θ about the center point P0 of the seal member 60.

  An electromagnetic drive unit that drives the valve body is accommodated in the main body 32. The electromagnetic drive part has a coil etc. which generate | occur | produces the electromagnetic attraction force which drives a valve body by supplying with electricity. The coil is electrically connected to the connector portion 34. The connector portion 34 is further electrically connected to a control device (not shown).

  The connector 34 receives a pulse current from the control device and supplies this pulse current to the coil. Due to the pulse current supplied to the coil, an electromagnetic attractive force is generated intermittently in the coil, and the valve element reciprocates in the axial direction of the fuel injection valve 30 due to the generated electromagnetic attractive force. The nozzle hole is opened and closed by the reciprocating movement of the valve body.

  In this embodiment, the injection part 31 and the main-body part 32 have a metal body. The above-described valve body and electromagnetic drive unit are accommodated in the body. In the present embodiment, the body has the stepped portion 36 and the like as described above, and the surface shape is complicated. Therefore, to obtain a predetermined shape after forming a rough shape by forging or casting. It is formed by performing removal processing such as cutting and grinding on the surface of the body.

  The fuel introduction part 35 is disposed on the opposite side of the connector part 34 from the injection part 31. The fuel introduction part 35 is a part for introducing fuel from the outside. The fuel introduction unit 35 is connected to the fuel pipe 70, and fuel is introduced from the fuel pipe 70. The fuel pipe 70 communicates with a fuel tank (not shown), and has a fuel pump device that sucks fuel in the fuel tank and pressurizes it to discharge it toward the fuel injection valve 30. In the fuel pump device, the fuel is discharged up to about 20 MPa. An O-ring 73 that fills a gap formed between the fuel introduction part 35 and the fuel pipe 70 is attached to the fuel introduction part 35.

  As described above, when the fuel whose pressure has been increased flows through the fuel pipe 70 and this fuel pressure acts on the fuel introduction portion 35, a force in the insertion direction is generated at the fuel injection valve 30. The fuel pipe 70 is fixed to an intake manifold (not shown) connected to the engine 10 or the intake passage 16.

  A holding member 80 is mounted between an end 71 on the fuel injection valve 30 side in the fuel pipe 70 and an end 33 on the fuel pipe 70 side in the main body 32. The holding member 80 is inserted into the mounting hole 20 with the fuel injection valve 30 attached to the fuel pipe 70, and biases the fuel injection valve 30 in the insertion direction with the fuel pipe 70 fixed at a predetermined position. .

  The pressing member 80 is made of metal and includes a support portion 81, a biasing portion 82, a restricting portion 83, and the like. The support portion 81 is supported by the end portion 33 of the main body portion 32 and has a shape that sandwiches the side wall of the connector portion 34.

  The urging portion 82 has a shape like a cantilever, and one end portion is fixed to the support portion 81 and the other end portion is a free end. The other end of the biasing portion 82, which is a free end, is in contact with the end portion 71 of the bent fuel pipe 70 in a state where the fuel injection valve 30 and the fuel pipe 70 are connected.

  Thus, since the support part 81 and the urging | biasing part 82 are comprised, the fuel injection valve 30 is urged | biased by the restoring force of the urging | biasing part 82 toward the insertion direction. The restoring force of the urging unit 82 is such a force that the fuel injection valve 30 does not come out of the mounting hole 20 even if the pressure of the combustion gas in the combustion chamber 15 acts on the injection unit 31.

  The restricting portion 83 restricts relative rotation between the fuel injection valve 30 and the fuel pipe 70. The restricting portion 83 extends from the support portion 81 toward the fuel pipe 70 and is inserted into an insertion hole 72 formed in the fuel pipe 70. Thereby, the relative rotation of the fuel injection valve 30 and the fuel pipe 70 is restricted.

  As shown in FIG. 2, a washer 40 is disposed between the flat surface 24 of the mounting hole 20 and the spherical surface 36 of the fuel injection valve 30. The washer 40 is made of metal, for example, stainless steel, and is disposed between the mounting hole 20 and the fuel injection valve 30 in a state where the fuel injection valve 30 is inserted into the mounting hole 20. The fuel injection valve 30 is supported.

  The washer 40 is a component that is in close contact with the fuel injection valve 30 and also in close contact with the mounting hole 20 to ensure airtightness in the mounting hole 20. The washer 40 supports the fuel injection valve 30 and is resistant to vibrations from the engine 10, heat resistance enough to withstand heat from the engine 10, and deterioration resistance to mixed gas and combustion gas. Is required. In short, the material for forming the washer 40 may be any material that satisfies this condition. In addition to the above conditions, it is preferable that the material itself has a damping function.

  Next, the operation of the fuel injection valve 30 will be briefly described.

  When the driver starts the engine 10, the fuel pump device is driven. The fuel pump device sucks and pressurizes the fuel in the fuel tank. The fuel increased to a predetermined pressure is discharged from the fuel pump device. The fuel discharged from the fuel pump device passes through the fuel pipe 70 and is introduced into the fuel injection valve 30 from the fuel introduction part 35.

  When the connector portion 34 receives a current from the control device in a state where fuel is introduced into the fuel injection valve 30, the current is passed through the coil. When this current is supplied to the coil, an electromagnetic attractive force is generated. The valve body moves in the valve opening direction by this electromagnetic attractive force.

  Thereby, the injection hole is opened, and the fuel introduced into the fuel injection valve 30 is injected from the injection unit 31 toward the combustion chamber 15. The valve opening operation of the valve body continues for a period during which current is supplied to the connector section 34. When the supply of current to the connector portion 34 stops, the valve element moves in the valve closing direction and closes the nozzle hole. Thereby, the fuel injection from the injection part 31 stops.

(Characteristic part)
Next, the washer 40, which is a characteristic part of the present embodiment, will be described in detail with reference to FIGS.

  The washer 40 includes a main body portion 41, an upper contact portion 42 formed on the spherical surface 36 side of the main body portion 41, and a lower contact portion 43 formed on the flat surface 24 side of the main body portion 41.

  The main body 41 is formed in an annular shape. The upper contact portion 42 is formed over the entire circumference at a position facing the spherical surface 36. The upper contact portion 42 contacts the spherical surface 36 in a state where the fuel injection valve 30 is attached to the attachment hole 20. The upper contact portion 42 forms a conical surface 42 composed of a surface inclined toward the axis S3 of the washer 40. The conical surface 42 is rotated by rotating a line at a position away from the axis S3 such that the distance from the axis S3 becomes smaller toward the insertion direction of the fuel injection valve 30 about the axis S3 as a rotation axis. It is a surface to be obtained.

  The conical surface 42 formed in this way is in line contact with the surface of the spherical surface 36 over the entire circumference. This line contact is annular and is not interrupted. In the present embodiment, the upper contact structure 50 is formed by contacting the spherical surface 36 and the conical surface 42.

  The lower contact portion 43 is formed over the entire circumference at a position facing the flat surface 24. The lower contact portion 43 contacts the flat surface 24 in a state where the fuel injection valve 30 is attached to the attachment hole 20. The lower contact portion 43 protrudes toward the flat surface 24 and forms an annular protrusion 43 that contacts the flat surface 24. The area of the protrusion 43 in contact with the plane 24 is very small compared to the area of the plane 24.

  The plane 24 and the protrusion 43 are in contact with each other by line contact. This line contact is annular and is not interrupted. In the present embodiment, the lower contact structure 51 is formed by the contact between the flat surface 24 and the protrusion 43.

  Next, the operation of the washer 40 when the fuel injection valve 30 is attached to the attachment hole 20 will be described. Here, as shown in FIG. 3, when the fuel injection valve 30 is attached to the attachment hole 20 in a state where the axis S1 of the fuel injection valve 30 is inclined by the angle θ with respect to the axis S2 of the attachment hole 20. Let's take an example.

  When the axis S1 is inclined with respect to the axis S2 by the angle θ about the center point P0, the axis S1 is also inclined with respect to the axis S3 of the washer 40. Even in such a state, the upper contact structure 50 can maintain contact between the spherical surface 36 and the conical surface 42. This is because the shape of the spherical surface 36 is always circular regardless of the cross section.

  According to this, even if the axial center S1 of the fuel injection valve 30 is inclined with respect to the axial center S3 of the washer 40, the spherical surface 36 has the above-described properties, and thus the washer over the entire circumference. It contacts 40 conical surfaces 42. At this time, the washer 40 translates along the plane 24 in the direction in which the fuel injection valve 30 is inclined.

  According to the upper contact structure 50, even if the axis S1 of the fuel injection valve 30 and the axis S2 of the mounting hole 20 are displaced, the contact state between the washer 40 and the fuel injection valve 30 can be maintained, and the fuel injection An axial deviation between the valve 30 and the mounting hole 20 can be allowed. In the present embodiment, the contact between the spherical surface 36 and the conical surface 42 is a line contact, so that a relatively high contact pressure can be obtained and the sealing performance can be improved. In the present embodiment, as described above, the upper contact structure 50 is an axis misalignment absorbing structure that can allow the axis misalignment between the fuel injection valve 30 and the mounting hole 20.

  On the other hand, since the flat surface 24 is a surface along the moving direction of the washer 40, the contact state between the flat surface 24 and the protrusion 43 is maintained. Further, since the contact between the flat surface 24 and the protrusion 43 is a line contact, the close contact state between the washer 40 and the mounting hole 20 can be maintained. According to the lower contact structure 51, a relatively high contact pressure can be obtained as compared with the structure of the prior art, and the sealing performance can be improved. In the present embodiment, as described above, the lower contact structure 51 has a close contact structure that can ensure a close contact state between the washer 40 and the mounting hole 20.

  Therefore, according to the mounting structure of the fuel injection valve 30 having the shaft misalignment absorbing structure 50 and the close contact structure 51, the air tightness in the mounting hole 20 is improved while allowing the shaft misalignment between the fuel injection valve 30 and the mounting hole 20. Therefore, it is possible to provide the mounting structure of the fuel injection valve 30 and the washer 40 used therefor.

  Further, in the present embodiment, since the annular seal member 60 that fills the gap between the fuel injection valve 30 and the mounting hole 20 is attached to the injection unit 31, the airtightness in the mounting hole 20 is further improved.

  Here, in this embodiment, the end of the mounting hole 20 on the cylinder block 11 side opens into the combustion chamber 15 so that the fuel injected by the fuel injection valve 30 can be directly supplied to the combustion chamber 15. In the engine 10 of this type, it is important to ensure airtightness in the mounting hole 20 so that mixed gas and combustion gas do not leak to the outside.

  According to the mounting structure as in the present embodiment, airtightness in the mounting hole 20 can be ensured even in the washer 40, and thus is particularly effective for the engine 10 of the type as in the present embodiment.

  In the present embodiment, the spherical surface 36 is formed between the injection unit 31 and the main body 32, but this need not be the case. For example, the spherical surface 36 may be formed on the side wall portion of the injection unit 31, or may be formed on the side wall portion of the main body portion 32.

  In the present embodiment, the mounting hole 20 is formed in the cylinder head 12 so that the fuel injection valve 30 is arranged coaxially with the cylinder 13, but this need not be the case. For example, the mounting hole 20 may be formed in the cylinder block 11 or the cylinder head 12 at the side of the cylinder 13 so that the axis S1 of the fuel injection valve 30 and the axis of the cylinder 13 intersect.

  In the present embodiment, the upper contact structure 50 corresponds to the “first contact structure” recited in the claims, and the lower contact structure 51 corresponds to the “second contact structure” recited in the claims. Further, the upper contact structure 50 is an “axial misalignment absorbing structure” composed of “spherical surface” and “conical surface” recited in the claims. Further, the lower contact structure 51 is a “contact structure” composed of a “plane” and a “projection” described in the claims.

  Furthermore, in the present embodiment, the upper contact portion 42 corresponds to “first contact portion” and “conical surface” described in the claims, and the lower contact portion 43 corresponds to “second contact” described in the claims. Part "and" projection part ". Further, the stepped portion 36 corresponds to a “spherical surface” described in the claims, and the seat portion 24 corresponds to a “receiving portion” described in the claims.

  Next, a method for manufacturing the washer 40 of this embodiment will be briefly described.

  In the washer 40 of the present embodiment, the upper contact portion 42 is a conical surface 42, and the lower contact portion 43 is a protrusion 43.

  The washer 40 of this embodiment is created by press working. The washer 40 is created by placing a metal ring member as a material of the washer 40 between a pair of molds, and then sandwiching the ring member with a mold. A shape corresponding to the conical surface 42 and the protrusion 43 is formed on the inner wall of the mold. The conical surface 42 and the protrusion 43 can be formed on the annular main body 41 by a single operation of sandwiching the annular member between a pair of molds.

  Here, in general, when forming the surface of an article into a predetermined shape, it is easier to process the conical surface 42 and the flat surface 24 than the spherical surface 36 and the protrusion 43. Further, as described above, the body of the cylinder head 12 and the fuel injection valve 30 has a more complicated shape than the washer 40, and a complicated shape such as the spherical surface 36 cannot be obtained by casting or forging. For this reason, in order to form the spherical surface 36 and the protrusion 43 on the body of the cylinder head 12 and the fuel injection valve 30, it is necessary to adjust the shape by casting after forging or forging.

  On the other hand, the washer 40 has a relatively simple shape compared to the body of the cylinder head 12 and the fuel injection valve 30 called an annular member, so even if the washer 40 has the protrusion 43 on the surface shape, The protrusion 43 can be obtained only by pressing. Therefore, by forming the protrusion 43 on the washer 40, the overall manufacturing cost of the engine 10, the fuel injection valve 30, the washer 40, and the like can be reduced.

(Second Embodiment)
The second embodiment of the present invention is a modification of the first embodiment.

  In the second embodiment, as shown in FIG. 4, the step portion 36a of the fuel injection valve 30 forms a flat surface 36a. The step portion 36a corresponds to a “receiving portion” recited in the claims.

  Further, the seat portion 24a of the mounting hole 20 forms a spherical surface 24a. The spherical surface 24a is a spherical surface that protrudes on the opposite side to the insertion direction. The spherical surface 24a is composed of a part of the surface (broken line) of a sphere having a radius R2 centered on the axis S2 of the mounting hole 20.

  The upper contact portion 42a of the washer 40 forms a projection 42a, and the lower contact portion 43a forms a conical surface 43a. The conical surface 43a rotates about a line at a position away from the axis S3 such that the distance from the axis S3 of the washer 40 increases toward the insertion direction of the fuel injection valve 30, with the axis S3 as a rotation axis. It is a surface obtained by making it.

  In the present embodiment, the upper contact structure 50 is a close contact structure constituted by a flat surface 36a and a protrusion 42a, and the lower contact structure 51 is an axis deviation absorbing structure constituted by a conical surface 43a and a spherical surface 24a. ing.

  In this embodiment, the washer 40 is formed with the protrusion 42a having a relatively complicated shape, so that it is not necessary to form this shape on the engine 10 or the fuel injection valve 30. For this reason, the whole manufacturing cost of the engine 10, the fuel injection valve 30, the washer 40, etc. can be held down.

(Third embodiment)
The third embodiment of the present invention is a modification of the first embodiment.

  In the third embodiment, as shown in FIG. 5, the step portion 36b of the fuel injection valve 30 forms a flat surface 36b. The step portion 36b corresponds to a “receiving portion” described in the claims.

  Further, the seat portion 24b of the mounting hole 20 forms a conical surface 24b. The conical surface 24b has a line at a position away from the axis S2 such that the distance from the axis S2 of the mounting hole 20 becomes smaller toward the insertion direction of the fuel injection valve 30, and the axis S2 is the rotation axis. It is a surface obtained by rotating.

  And the upper contact part 42b of the washer 40 forms the projection part 42b, and the lower contact part 43b forms the spherical surface 43b. The spherical surface 43b is formed of a part of the surface (broken line) of a sphere having a radius R3 and having a center on the axis S3 of the washer 40.

  In the present embodiment, the upper contact structure 50 is a close contact structure constituted by a flat surface 36b and a protrusion 42b, and the lower contact structure 51 is an axis deviation absorbing structure constituted by a conical surface 24b and a spherical surface 43b. ing.

  In this embodiment, since the projection 42b and the spherical surface 43b having relatively complicated shapes are formed on the washer 40, it is not necessary to form these shapes on the engine 10 and the fuel injection valve 30. For this reason, the whole manufacturing cost of the engine 10, the fuel injection valve 30, the washer 40, etc. can be held down.

(Fourth embodiment)
The fourth embodiment of the present invention is a modification of the first embodiment.

  In the fourth embodiment, as shown in FIG. 6, the stepped portion 36c of the fuel injection valve 30 forms a conical surface 36c. The conical surface 36c is a line located at a position away from the axis S1 such that the distance from the axis S1 of the fuel injection valve 30 increases toward the insertion direction of the fuel injection valve 30, and the axis S1 is the axis of rotation. It is a surface obtained by rotating as.

  The upper contact portion 42c of the washer 40 forms a spherical surface 42c. The spherical surface 42c is a part of the surface (broken line) of a sphere having a radius R4 centered on the axis S3 of the washer 40.

  The seat portion 24c of the mounting hole 20 forms a flat surface 24c. The seat portion 24c corresponds to a “receiving portion” described in the claims. And the downward contact part 43c of the washer 40 forms the projection part 43c.

  In the present embodiment, the upper contact structure 50 is an axis misalignment absorbing structure composed of a spherical surface 42c and a conical surface 36c, and the lower contact structure 51 is a close contact structure composed of a flat surface 24c and a protrusion 43c. ing.

  In this embodiment, since the spherical surface 42c and the projection 43c having a relatively complicated shape are formed on the washer 40, it is not necessary to form these shapes on the engine 10 and the fuel injection valve 30. For this reason, the whole manufacturing cost of the engine 10, the fuel injection valve 30, the washer 40, etc. can be held down.

(Fifth embodiment)
The fifth embodiment of the present invention is a modification of the first embodiment.

  In the fifth embodiment, as shown in FIG. 7, the step portion 36d of the fuel injection valve 30 forms a spherical surface 36d, and the seat portion 24d of the mounting hole 20 forms a projection portion 24d. The upper contact portion 42d of the washer 40 forms a conical surface 42d, and the lower contact portion 43d forms a flat surface 43d. The lower contact portion 43d corresponds to a “receiving portion” described in the claims.

  Instead of forming the protrusion 24d on the washer 40 as in this embodiment, it may be formed on the seat 24d.

  In the present embodiment, the upper contact structure 50 is an axis misalignment absorbing structure composed of a spherical surface 36d and a conical surface 42d, and the lower contact structure 51 is a close contact structure composed of a flat surface 43d and a protrusion 24d. ing.

(Other embodiments)
In the above, a plurality of embodiments have been described.

  The present invention is not construed as being limited to the above-described embodiments, and can be applied to various embodiments without departing from the scope of the invention.

  As long as the mounting structure of the fuel injection valve 30 has an axis deviation absorbing structure and a close contact structure, which structure is adopted as the upper contact structure 50 and the lower contact structure 51 is free. Further, if the shaft misalignment absorbing structure has a conical surface and a spherical surface, and the close contact structure has a protrusion and a receiving part for receiving the protrusion, the step part 36 of the fuel injection valve 30, the seat part 24 of the mounting hole 20, Which shape is adopted for the upper contact portion 42 and the lower contact portion 43 of the washer 40 is also free.

  The fuel injection valve 30 may be employed in a port injection type gasoline engine. In this case, the attachment hole 20 is formed so as to open to the intake passage 16. Further, this mounting structure may be adopted not for a gasoline engine but for a diesel engine.

  10 Engine, 11 Cylinder block, 12 Cylinder head, 20 Mounting hole, 24 Seat part / plane (receiving part), 30 Fuel injection valve, 31 Injection part, 36 Step part / spherical surface, 40 Washer, 41 Body part, 42 Upper contact Part / conical surface (first contact part), 43 lower contact part / protrusion part (second contact part), 50 upper contact structure (axial displacement absorbing structure), 51 lower contact structure (adhesion structure), 60 seal member

Claims (14)

A fuel injection valve mounting structure for attaching a fuel injection valve having an injection portion for injecting fuel to an end portion in a mounting hole formed in an internal combustion engine,
An annular seat that receives a load from the fuel injection valve in a state in which the fuel injection valve is attached to the internal combustion engine is formed in the attachment hole,
The fuel injection valve is formed with an annular step portion facing the seat portion in the insertion direction,
Between the said seat part and the said level | step difference part, the cyclic | annular washer which has the 1st contact part which contacts the said level | step difference part, and the 2nd contact part which contacts the said seat part, and supports the said fuel injection valve is arrange | positioned. And
A first contact structure is formed by contacting the first contact portion and the stepped portion, and a second contact structure is formed by contacting the second contact portion and the seat portion,
The first contact structure can maintain the contact state between the washer and the step portion of the fuel injection valve even when the axis of the fuel injection valve is displaced from the axis of the mounting hole. Axis misalignment absorption structure
The second contact structure is a close contact structure in which the washer and the seat portion of the mounting hole are in close contact with each other,
The shaft misalignment absorbing structure is a conical surface composed of a surface inclined toward the shaft center of the washer or the fuel injection valve, and a spherical surface composed of a part of the surface of a sphere contacting the conical surface over the entire circumference. Configured
The fuel injection valve mounting structure, wherein the close contact structure includes an annular protrusion and a receiving part that receives and contacts the protrusion. A fuel injection valve mounting structure for attaching a fuel injection valve having an injection portion for injecting fuel to an end portion in a mounting hole formed in an internal combustion engine,
An annular seat that receives a load from the fuel injection valve in a state in which the fuel injection valve is attached to the internal combustion engine is formed in the attachment hole,
The fuel injection valve is formed with an annular step portion facing the seat portion in the insertion direction,
Between the said seat part and the said level | step difference part, the cyclic | annular washer which has the 1st contact part which contacts the said level | step difference part, and the 2nd contact part which contacts the said seat part, and supports the said fuel injection valve is arrange | positioned. And
A first contact structure is formed by contacting the first contact part and the stepped part, and a second contact structure is formed by contacting the second contact part and the seat part,
The first contact structure is a close contact structure in which the washer and the step portion of the fuel injection valve are in close contact with each other,
The second contact structure can maintain the contact state between the washer and the step portion of the fuel injection valve even when the axis of the fuel injection valve is displaced from the axis of the mounting hole. It has an off-axis absorption structure,
The shaft misalignment absorbing structure is composed of a conical surface made of a surface inclined toward the axial center of the washer or the mounting hole, and a spherical surface made of a part of the surface of a sphere contacting the conical surface over the entire circumference. And
The fuel injection valve mounting structure, wherein the close contact structure includes an annular protrusion and a receiving part that receives and contacts the protrusion.   The fuel injection valve mounting structure according to claim 1, wherein the first contact portion is the spherical surface.   The fuel injection valve mounting structure according to claim 1, wherein the second contact portion is the annular protrusion.   The fuel injection valve mounting structure according to claim 2, wherein the second contact portion is the spherical surface.   The fuel injection valve mounting structure according to claim 2, wherein the first contact portion is the annular protrusion.   The fuel injection valve according to any one of claims 1 to 6, wherein an annular seal member that fills a gap between the attachment hole and the fuel injection valve is attached to the injection portion. Mounting structure. An end of the mounting hole on the insertion direction side opens to a combustion chamber provided in the internal combustion engine,
The fuel injection valve mounting structure according to any one of claims 1 to 7, wherein the injection section is disposed in the mounting hole so that fuel can be directly injected into the combustion chamber. Between an attachment hole formed in an internal combustion engine and having an annular seat on the inner wall, an injection part for injecting fuel at the end, and a fuel injection valve having an annular step on the side wall facing the seat in the insertion direction In the washer of the fuel injection valve that is disposed at and supports the fuel injection valve
A body portion formed in an annular shape;
A first contact portion that is formed on the step portion side of the main body portion and forms a first contact structure by contacting the step portion;
A second contact portion formed on the seat portion side of the main body portion and forming a second contact structure by contacting the seat portion;
The first contact structure can maintain the contact state between the washer and the step portion of the fuel injection valve even when the axis of the fuel injection valve is displaced from the axis of the mounting hole. Axis misalignment absorption structure
The second contact structure is a close contact structure in which the washer and the seat portion of the mounting hole are in close contact with each other,
The shaft misalignment absorbing structure is a conical surface composed of a surface inclined toward the shaft center of the washer or the fuel injection valve, and a spherical surface composed of a part of the surface of a sphere contacting the conical surface over the entire circumference. Configured
The close contact structure is composed of an annular protrusion and a receiving part that receives and contacts the protrusion,
One of the conical surface and the spherical surface is formed on the first contact portion, and one of the annular protrusion and the receiving portion is formed on the second contact portion. The washer of the injection valve. Formed in the internal combustion engine, disposed between a mounting hole having a seat portion on an inner wall, an injection portion for injecting fuel to an end portion, and a fuel injection valve having a step portion facing the seat portion in the insertion direction on a side wall; In the washer of the fuel injection valve that supports the fuel injection valve,
A body portion formed in an annular shape;
A first contact portion that is formed on the step portion side of the main body portion and forms a first contact structure by contacting the step portion;
A second contact portion formed on the seat portion side of the main body portion and forming a second contact structure by contacting the seat portion;
The first contact structure is a close contact structure in which the washer and the step portion of the fuel injection valve are in close contact with each other,
The second contact structure can maintain the contact state between the washer and the step portion of the fuel injection valve even when the axis of the fuel injection valve is displaced from the axis of the mounting hole. It has an off-axis absorption structure,
The shaft misalignment absorbing structure is composed of a conical surface made of a surface inclined toward the axial center of the washer or the mounting hole, and a spherical surface made of a part of the surface of a sphere contacting the conical surface over the entire circumference. And
The close contact structure is composed of an annular protrusion and a receiving part that receives and contacts the protrusion,
One of the annular protrusion and the receiving portion is formed on the first contact portion, and one of the conical surface and the spherical surface is formed on the second contact portion. The washer of the injection valve.   The washer for a fuel injection valve according to claim 9, wherein the first contact portion is the spherical surface.   The washer for a fuel injection valve according to claim 9 or 11, wherein the second contact portion is the annular protrusion.   The washer of a fuel injection valve according to claim 10, wherein the second contact portion is the spherical surface.   The washer for a fuel injection valve according to claim 10 or 13, wherein the first contact portion is the annular protrusion.

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