JP5093123B2 - Mounting structure of fuel injection valve - Google Patents

Description

  The present invention relates to a mounting structure for a fuel injection valve (injector) for injecting fuel into a cylinder head of an engine.

  Conventionally, a fuel injection valve mounting structure is known in Patent Document 1 and the like. In this structure, as shown in FIG. 8, an elastic member 4c serving as an intermediate ring is sandwiched between two rigid rings 4a and 4b.

  That is, this structure functions as a compensation element for the fuel injection valve 1 that can be inserted into the mounting hole 3 provided in the cylinder head 2 of the engine. And it has the rigid 1st ring 4a which can contact | abut in the radial direction of the inclination part 17 of the fuel injection valve 1. FIG.

  A rigid second ring 4 b is inserted into the mounting hole 3. An elastic drum-shaped intermediate ring 4c disposed between the rigid first and second rings 4a and 4b is non-detachably coupled to the first ring 4a and the second ring 4b. .

JP-T-2004-506136

  In the case of this prior art, when the elastic member 4c receives vibration or pressure, the elastic member 4c bulges and deforms in the radial direction, and sometimes protrudes outside the ring toward the gap in the radial direction as indicated by a broken line in FIG. . In this case, the damping force is reduced due to a reduction in the thickness of the elastic member 4c in the axial direction (vertical direction in FIG. 8). Or, in an extreme case, there is a problem of aged deterioration in which the vibration damping effect is affected by the metal contact between the first ring 4a and the second ring 4b.

  The present invention has been made paying attention to such problems existing in the prior art, and its purpose is to prevent the elastic member from protruding and to prevent the first ring 4a and the second ring 4b from protruding. It is an object of the present invention to provide a fuel injection valve mounting structure capable of maintaining the vibration damping action of a corresponding shaft deviation absorbing washer over a long period of time.

In order to achieve the above object, the present invention employs the following technical means. That is, in the invention described in claim 1, the fuel injection valve (1) having the inclined portion (17) between the housing portions having different outer diameters is mounted on the cylinder head (2) of the engine. In the mounting structure of the fuel injection valve that is inserted into and fixed to the hole (3), the shaft misalignment absorbing washer (4) is in contact with the inclined portion (17), and the mounting hole (3) is the shaft misalignment absorbing washer (4). Receiving the shaft misalignment absorbing washer (4) so as to be slidable in the radial direction. The shaft misalignment absorbing washer (4) includes a concave ring (4a) having a recess (4a1) and The ring-shaped elastic member (4c) is inserted into the concave portion (4a1) of the concave ring (4a). The convex ring (4b) is connected to the concave ring (4a). Formed separately and fitted with concave ring (4a) Inserted protrusion in a concave ring (4a) of which encloses the recessed ring (4a) and the convex ring (4b) and de elastic member (4c), a convex-shaped ring (4b) and (4b1) is hemispherical It is characterized by any one of a shape, a trapezoidal shape, and a triangular shape .

According to the first aspect of the present invention, vibrations from the fuel injection valve (1) to the cylinder head (2) are attenuated by the elastic member (4c) by enclosing the elastic member (4c). . In addition, the elastic member (4c) can be prevented from protruding in the radial direction, and deterioration over time can be reduced. Further, since the convex portion (4b1) is any one of a hemispherical shape, a trapezoidal shape, and a triangular shape with a sharp tip, the elastic member (4c) is easily elastically deformed and vibration absorption can be easily performed.

  Next, in the invention described in claim 2, the portion that becomes the contact point (18, 19) with respect to the inclined portion (17) of the axial deviation absorbing washer (4) is any of a tapered portion, a curved surface portion, and a hemispherical portion. It is characterized by being formed by.

  According to the second aspect of the present invention, the portion that contacts the inclined portion (17) is formed by any one of the tapered portion, the curved surface portion, and the hemispherical portion of the shaft misalignment absorbing washer (4). When the injection valve (1) is mounted with shaft misalignment, the shaft misalignment absorbing washer (4) moves in the radial direction on the washer receiving portion (16) so that the pressure applied to the fuel injection valve is less biased. Can be received at the contact points (18, 19) of the shaft displacement absorbing washer (4).

Next, the invention described in claim 3 is characterized in that the cross section of the elastic member (4c) inserted into the concave ring (4a) is triangular.

According to the third aspect of the invention, the axial dimension of the off-axis absorbing washer (4) can be reduced by the elastic member (4c) having a triangular cross section, and a low height structure can be obtained. .

Next, in the invention according to claim 4 , the elastic member (4c) is enclosed by the concave ring (4a) and the convex ring (4b), and the entire elastic member (4c) is buried in the concave portion (4a1). It is characterized by being.

According to the fourth aspect of the present invention, since the entire elastic member (4c) is buried in the recess (4a1), it is possible to completely prevent the elastic member (4c) from protruding.

Next, in the invention according to claim 5 , the fuel injection valve (1) having the inclined portion (17) between the housing portions having different outer diameters is formed in the cylinder head (2) of the engine. In the fuel injection valve mounting structure that is inserted into and fixed to the mounting hole (3), the shaft displacement absorbing washer (4) is in contact with the inclined portion (17), and the mounting hole (3) is connected to the shaft displacement absorbing washer (4). ) And a step portion (15) for supporting the axial displacement absorbing washer (4) so as to be slidable in the radial direction. The axial deviation absorbing washer (4) has a concave ring (4a) having a concave portion (4a1). And a convex ring (4b), and a ring-shaped elastic member (4c) is inserted into the concave portion (4a1) of the concave ring (4a). The convex ring (4b) is a concave ring (4a). And is formed as a separate body and fitted with the concave ring (4a) Type ring (4a) and which encloses an elastic member (4c) out with convex ring (4b), the convex portion of the convex ring (4b) (4b1) has been inserted inside the elastic member (4c) The convex ring (4b) is connected to the concave ring (4a) only through the elastic member (4c).

According to the fifth aspect of the present invention, since the convex ring (4b) is connected to the concave ring (4a) only through the elastic member (4c), the fuel injection valve (1) to the cylinder head ( The elastic member (4c) can be surely interposed in the vibration and heat path toward 2), and the vibration and heat blocking effect is excellent.

  In addition, the code | symbol in the parenthesis as described in a claim and said each means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

1 is a partial cross-sectional view of a fuel injection valve mainly showing a state in which a fuel injection valve according to a first embodiment of the present invention is correctly attached to an attachment hole of a cylinder head. FIG. 3 is a partial cross-sectional view of mainly a shaft misalignment absorbing member portion that is a main part in the first embodiment. It is a partial cross section figure of the axis gap absorption washer used for a 2nd embodiment. It is a partial cross section figure of the axis gap absorption washer used for a 3rd embodiment. It is a partial cross section figure of the axis shift absorption washer used for a 4th embodiment. It is a partial cross section figure of the axis gap absorption washer used for a 5th embodiment. It is a partial cross section figure of the axis shift absorption washer used for a 6th embodiment. It is a partial sectional view mainly of a shaft displacement absorbing washer portion in a conventional mounting structure.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2. FIG. 1 is a partial cross-sectional view of the fuel injection valve 1 mainly showing a state in which the fuel injection valve 1 is correctly mounted in the mounting hole 3 of the cylinder head 2 of the engine. FIG. It is a partially expanded sectional view of 4 parts.

  In FIG. 1, the upper portion of the fuel injection valve 1 is press-fitted through a fuel rail formed of a metal fuel pipe 5 via an O-ring 6. The O-ring 6 is shown in a state before being press-fitted and deformed. When the fuel pipe 5 is completely attached, the position of the fuel pipe 5 is lowered to the position of the two-dot chain line 5a in FIG. An electric signal is introduced into the fuel injection valve 1 via the connector 7.

  By this electric signal, the needle inside the fuel injection valve 1 moves in the vertical direction by the action of a magnetic circuit and a spring that form a drive circuit (not shown). As a result, a valve body (not shown) at the lower end of the fuel injection valve 1 is opened and closed. As this valve element opens and closes, vibration or noise that cannot be ignored occurs. This vibration adversely affects other engine sensors, particularly knock sensors.

  An electromagnetic coil (not shown) constituting the magnetic circuit is housed in a housing 9 that forms the large diameter portion 8. The large-diameter portion 8 serves as a magnetic flux passage (yoke) that flows by excitation of the electromagnetic coil.

  A valve body (not shown) is accommodated in a nozzle portion that forms the small diameter portion 10. A medium diameter portion 11 is provided between the small diameter portion 10 and the large diameter portion 8.

  The fuel injection valve 1 is mounted in the mounting hole 3 of the cylinder head 2 via a shaft deviation absorbing member 4. The shaft misalignment absorbing member 4 is composed of a ring-shaped shaft misalignment absorbing washer. As shown in an enlarged view in FIG. 2, the shaft misalignment absorbing washer 4 is divided into a ring-shaped inclined portion side member 4a, a ring-shaped step portion side member 4b, and an elastic member 4c serving as an intermediate ring. . In the first embodiment, the inclined portion side member 4a is composed of a concave ring (hereinafter referred to as a concave ring 4a) having a concave portion 4a1 on the lower side. Further, the step portion side member 4b includes a convex ring (hereinafter referred to as a convex ring 4b) having a convex portion 4b1 on the upper side (fuel pipe 5 side).

  An elastic member 4c made of fluorine-based rubber is inserted into the concave portion 4a1 of the concave ring 4a. The elastic member 4c constitutes an intermediate ring provided between the concave ring 4a and the convex ring 4b having high rigidity, and is made of a material that is more elastically deformed than the concave ring 4a and the convex ring 4b, for example, an elastomer. It is configured.

  The convex ring 4b is formed separately from the concave ring 4a and is fitted to the concave ring 4a. And it is comprised so that the elastic member 4c may be enclosed by the concave ring 4a and the convex ring 4b. In addition, it is separable between the concave ring 4a and the elastic member 4c, and between the convex ring 4b and the elastic member 4c.

  The elastic member 4c is a convex portion 4b1 of the convex ring 4b and is elastically deformed by being pressed in the concave portion 4a1. When the fuel injection valve 1 injects fuel into the cylinder head 2, when the fuel pulsation or the vibration of the fuel injection valve 1 is transmitted to the cylinder head 2 through the shaft misalignment absorbing washer 4, the elastic member 4 c attenuates the vibration. .

  Since the elastic member 4c is surrounded by the concave portion 4a1 and the convex portion 4b1 of the shaft misalignment absorbing washer 4, even if it receives a compressive force, it does not protrude to the outside and suppresses a decrease in the damping force after aging. it can. Further, as described above, the concave ring 4a and the elastic member 4c can be separated from each other, and the convex ring 4b and the elastic member 4c can be separated from each other, and there is no particular need for adhesion between these layers.

  The fuel injection valve 1 is pressurized against the mounting hole 3 by the pressure of the fuel, and receives the applied pressure by the shaft displacement absorbing washer 4. For this purpose, the step portion 15 on the inner periphery of the attachment hole 3 has a washer receiving portion 16 for receiving the axial deviation absorbing washer 4. The washer receiving portion 16 has a substantially flat portion so that the shaft misalignment absorbing washer 4 can slide in a direction orthogonal to the axis J1 (FIG. 2) of the fuel injection valve 1.

  The inclined portion 17 of the fuel injection valve 1 and the contact points 18 and 19 provided on the upper side (on the side opposite to the cylinder head 2) of the shaft displacement absorbing washer 4 come into contact with each other, so that the fuel injection valve 1 is inclined to the mounting hole 3. When attached, the shaft misalignment absorbing washer 4 slides on the washer receiving portion 16 of the step portion 15 facing the inclined portion 17.

  The contact points 18 and 19 of the shaft misalignment absorbing washer 4 are formed on the upper surface of the concave ring 4a, and the upper surface including the contact points 18 and 19 that contact the inclined portion 17 has a curved surface portion or inclined portion 4e. (Hereinafter simply referred to as the curved surface portion 4e).

  The upper end surface of the convex portion 4b1 inserted into the concave ring 4a is configured as a flat surface. The cross section of the axial displacement absorbing washer 4 has a curved surface portion 4e that contacts the inclined portion 17, a linear slip portion 4f, and an orthogonal wall portion 4g that is orthogonal to the slip portion 4f.

  A gap 20 is provided between the lower end peripheral portion 4h of the concave ring 4a and the flange portion 4i of the convex ring, and vibration absorption by elastic deformation of the elastic member 4c is possible. Further, the gap 20 reduces the propagation of heat and vibration. Therefore, harmful effects caused by vibration and heat can be suppressed.

  Clearances 25 a and 25 b are provided between the orthogonal wall portion 4 g of the shaft displacement absorbing washer 4 and the inner wall 3 a of the mounting hole 3. Since the clearances 25a and 25b are present, the axial displacement absorbing washer 4 slides in the radial direction (left and right direction in FIG. 2) when the fuel injection valve 1 is tilted, thereby biasing the applied pressure. You can take it without.

  A gas seal member 27, for example, tetrafluoroethylene resin (PTFE), is attached to the tip portion 26 of the fuel injection valve 1 in FIG. 1, and the gas seal member 27 has a small diameter between the fuel injection valve 1 and the mounting hole 3. When the fuel injection valve 1 is press-fitted between the hole 28 and the fuel injection valve 1 is inclined, the fuel injection valve 1 is inclined with the gas seal member 27 as a center point.

  And when it inclines, the inclination part 17 near the center of the fuel injection valve 1 slides relatively on the contact points 18 and 19 in FIG. 2 of the axial deviation absorbing washer 4.

  The inclined portion 17 is ideally a hemispherical surface on which automatic alignment is performed, but is a tapered portion for convenience of processing.

  The mounting hole 3 formed in the cylinder head 2 of the engine has a small-diameter hole 28, a medium-diameter hole 29, and a large-diameter hole 30 as shown in FIG. A first inclined surface 31 and a second inclined surface 32 exist between the small-diameter hole portion 28 and the medium-diameter hole portion 29. Further, the step portion 15 exists between the medium diameter hole portion 29 and the large diameter hole portion 30 as described above.

  In the case of FIG. 1 in which the fuel injection valve 1 is correctly attached, the left and right clearances 25a and 25b are provided uniformly on the left and right. However, when the fuel injection valve 1 is attached at an inclination, one of the clearances 25a and 25b is provided. Is smaller than the other. This is because the axial deviation absorbing washer 4 slides linearly in the radial direction.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. FIG. 3 is a partial cross-sectional view of a portion corresponding to the left side of FIG. 2 of the axial deviation absorbing washer 4 used in the second embodiment. In the following embodiments, the same components as those in the first embodiment described above are denoted by the same reference numerals, description thereof is omitted, and different configurations and features are mainly described. In addition, FIG.1 and FIG.2 is used.

  In FIG. 3, the shaft misalignment absorbing washer 4 is divided into two parts, an inclined portion side member 4a and a step portion side member 4b. In the second embodiment, the inclined portion side member 4a is configured as a concave ring 4a having a concave portion 4a1 on the lower side. The step portion side member 4b includes a convex ring 4b having a hemispherical convex portion 4b1 on the upper side (fuel pipe 5 side).

  The elastic member 4c is inserted into the concave portion 4a1 of the concave ring 4a. The convex ring 4b is formed separately from the concave ring 4a, and is fitted to the concave ring 4a so as to be convex with the concave ring 4a. The elastic member 4c is surrounded by the ring 4b.

  The elastic member 4c is made of rubber and is a hemispherical convex portion 4b1 of the convex ring 4b and is elastically deformed by being pressed in the concave portion 4a1. When the fuel injection valve 1 injects fuel into the cylinder head 2 (FIG. 1), when the fuel pulsation or the vibration of the fuel injection valve 1 is transmitted to the cylinder head 2 through the misalignment absorbing washer 4, the elastic member 4c Dampens vibrations.

  Further, the fuel injection valve 1 receives a pressure in the direction of the cylinder head 2 due to the high pressure of the fuel. Since the elastic member 4c is surrounded by the concave portion 4a1 and the convex portion 4b1 of the shaft misalignment absorbing washer 4, it does not protrude to the outside even if it receives the applied pressure, and can suppress a decrease in damping force after aging. .

  When the pressure is applied, the elastic member 4c is easily deformed by the hemispherical convex portion 4b1, and the end of the elastic member 4c enters the gap 4a2 in the concave portion, and the concave ring 4a is moved by the convex ring 4b. It can be firmly supported.

  Similarly to the first embodiment, the concave ring 4a and the convex ring 4b of the axial deviation absorbing washer 4 are made of metal. The entire cross section of the shaft misalignment absorbing washer 4 is orthogonal to the curved surface portion 4e that contacts the inclined portion 17 in FIG. 2, the linear sliding portion 4f that slides on the washer receiving portion 16, and the sliding portion 4f. It has an orthogonal wall 4g. And a clearance 25b (FIG. 2) equivalent part is provided between the orthogonal wall part 4g and the inner peripheral wall of the attachment hole 3 of FIG.

(Third embodiment)
Next, a third embodiment of the present invention will be described. FIG. 4 is a partial cross-sectional view of a portion corresponding to the left side of FIG. 2 of the axial deviation absorbing washer 4 used in the third embodiment. Features that are different from the embodiment described above will be mainly described. In the third embodiment, the cross section of the convex portion 4b1 at the tip portion inserted into the concave ring 4a of the convex ring 4b is trapezoidal. Therefore, processing is easier than in the second embodiment.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. FIG. 5 is a partial cross-sectional view of a portion corresponding to the left side of FIG. 2 of the shaft misalignment washer 4 used in the fourth embodiment. Features that are different from the embodiment described above will be mainly described. In the fourth embodiment, the cross section of the convex portion 4b1 inserted into the concave ring 4a of the convex ring 4b is an inclined surface. The inclined surface is inclined upward so that the left direction in FIG. 5, that is, the radial direction is the lower side of the inclined surface, and the right direction in the drawing is the upper side of the inclined surface. On the contrary, the structure inclined to the left upward may be sufficient.

  FIG. 5 shows a state before the pressure is applied. When the fuel injection valve 1 is mounted in the mounting hole 3 and the pressure is applied, the rubber that becomes the elastic member 4c is a convex ring. It is easily deformed by being pushed by the inclined surface of the convex portion 4b1 of 4b. As a result, the convex portion 4b1 bites into the elastic member 4c, and the gap 20 is reduced.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described. FIG. 6 is a partial cross-sectional view showing a pressurized state of the axial deviation absorbing washer 4 used in the fifth embodiment. Features that are different from the embodiment described above will be mainly described. In the fifth embodiment, the cross section of the tip portion inserted into the concave ring 4a of the convex ring 4b is a flat surface. Moreover, the compressed cross-sectional shape of the elastic member 4c is triangular.

  The elastic member 4c has a ring shape as a whole, and the longitudinal section of the left end portion of the ring-shaped rubber has a triangular shape as shown in FIG. The concave portion 4a1 in the concave ring 4a that wraps around the elastic member 4c is also triangular. The elastic member 4c has a substantially triangular cross section before being compressed, but has a longer axial height than after the compression.

  According to this configuration, it is possible to reduce the vertical dimension (height in the vertical direction in the drawing) along the axial direction of the entire axial displacement absorbing washer 4 including three parts.

(Sixth embodiment)
Next, a sixth embodiment of the present invention will be described. FIG. 7 is a partial cross-sectional view showing a pressurized state of the shaft misalignment absorbing washer 4 used in the sixth embodiment. Features that are different from the embodiment described above will be mainly described. In the sixth embodiment, the convex portion 4b1 of the convex ring 4b is inserted into the elastic member 4c, and the convex ring 4b is connected to the concave ring 4a only through the elastic member 4c.

  According to this configuration, since the convex ring 4b is connected to the concave ring 4a only through the elastic member 4c, in FIG. 1, in the vibration and heat path from the fuel injection valve 1 toward the cylinder head 2. The elastic member 4c of FIG. 7 can be surely interposed, and the effect of blocking vibration and heat is excellent. The concept of the sixth embodiment can also be applied to the structures of the respective embodiments shown in FIGS.

(Other embodiments)
The present invention is not limited to the above-described embodiments, and can be modified or expanded as follows. For example, in each of the embodiments described above, a ring-shaped rubber is used as the elastic member 4c. However, the elastic member 4c may be a spring or a leaf spring (e.g., a ring shape as a whole and a U-shaped section lying sideways). (Character shape) may be used.

  Further, although the rubber constituting the elastic member 4c and the concave ring 4a and between the rubber and the convex ring 4b (interlayer) are separable, they may be coupled by rubber vulcanization or adhesion. good.

  Further, the elastic member 4c may have a drum shape (the same shape as the conventional intermediate ring in FIG. 8) having a constricted central portion instead of a rectangular cross section. In this case, pressure is applied and the central portion expands.

  Further, in each of the embodiments described above, the shaft misalignment absorbing washer 4 has the inclined portion side member 4a as a concave ring and the stepped portion side member 4b as a convex ring, but conversely, the inclined portion side member 4a is a convex ring. The step portion side member 4b may be a concave ring.

DESCRIPTION OF SYMBOLS 1 ... Fuel injection valve 2 ... Engine cylinder head 3 ... Mounting hole 4 ... Axial deviation absorption washer 4a ... Concave ring 4b ... Convex ring 4a1 ... Concave part 4b1 ... Convex part 4c ... Elastic member 4e ... Slope part or curved surface part 5 ... Fuel pipe 8 ... Large diameter part 10 ... Small diameter part 11 ... Medium diameter part 15 ... Step part 16 ... Washer receiving part 17 ... Inclined part 18, 19 ... Contact part 25a, 25b ... Clearance

Claims (5)

Fuel injection in which a fuel injection valve (1) having an inclined part (17) between housing parts having different outer diameters is inserted and fixed in a mounting hole (3) formed in a cylinder head (2) of the engine. In the valve mounting structure,
A shaft displacement absorbing washer (4) is in contact with the inclined portion (17),
The mounting hole (3) has a step portion (15) that receives the shaft misalignment absorbing washer (4) and supports the shaft misalignment absorbing washer (4) so as to be slidable in the radial direction,
The off-axis absorbing washer (4) comprises a concave ring (4a) having a concave portion (4a1) and a convex ring (4b),
A ring-shaped elastic member (4c) is inserted into the concave portion (4a1) of the concave ring (4a),
The convex ring (4b) is formed separately from the concave ring (4a), and is fitted to the concave ring (4a) to form the concave ring (4a) and the convex ring (4b). Enclosing the elastic member (4c) ,
The fuel injection valve mounting structure , wherein the convex portion (4b1) inserted into the concave ring (4a) of the convex ring (4b) is hemispherical, trapezoidal, or triangular .   A portion that is a contact point (18, 19) of the shaft displacement absorbing washer (4) with respect to the inclined portion (17) is formed by any one of a tapered portion, a curved surface portion, and a hemispherical portion. The fuel injection valve mounting structure according to claim 1. The fuel injection valve mounting structure according to claim 1 or 2, wherein the elastic member (4c) inserted into the concave ring (4a) has a triangular cross section . The concave ring (4a) and the convex ring (4b) surround the elastic member (4c), and the entire elastic member (4c) is buried in the concave portion (4a1). Item 4. The fuel injection valve mounting structure according to any one of Items 1 to 3 . Fuel injection in which a fuel injection valve (1) having an inclined part (17) between housing parts having different outer diameters is inserted and fixed in a mounting hole (3) formed in a cylinder head (2) of the engine. In the valve mounting structure,
A shaft displacement absorbing washer (4) is in contact with the inclined portion (17),
The mounting hole (3) has a step portion (15) that receives the shaft misalignment absorbing washer (4) and supports the shaft misalignment absorbing washer (4) so as to be slidable in the radial direction,
The off-axis absorbing washer (4) comprises a concave ring (4a) having a concave portion (4a1) and a convex ring (4b),
A ring-shaped elastic member (4c) is inserted into the concave portion (4a1) of the concave ring (4a),
The convex ring (4b) is formed separately from the concave ring (4a), and is fitted to the concave ring (4a) to form the concave ring (4a) and the convex ring (4b). Enclosing the elastic member (4c),
The convex part (4b1) of the convex ring (4b) is inserted into the elastic member (4c), and the convex ring (4b) is inserted into the concave ring only through the elastic member (4c). mounting structure for fuel injection valve you characterized in that it is connected with (4a).

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