JP5845231B2 - Soundproof structure of internal combustion engine - Google Patents

Description

  The present invention relates to a soundproof structure for an internal combustion engine having a cover body and a foamed sound insulation member.

  As a soundproof structure for an internal combustion engine, for example, Patent Document 1 discloses a sound insulation cover that covers a range extending from above the cylinder head cover of the engine to above the fuel injection pump in front of the vehicle body. The sound insulation cover includes a resin outer cover member and a urethane inner sound insulation member fixed to the inside of the outer cover member.

  The soundproof structure disclosed in Patent Document 1 covers the upper side of a high-pressure pipe such as a common rail with a sound insulation cover, one end side of the inner sound insulation member abuts on the cooling water pipe, and the other end side of the inner sound insulation member serves as a cylinder head cover. It is comprised so that it may contact | abut.

Japanese Patent No. 4284780

  However, the soundproof structure disclosed in Patent Document 1 does not employ, for example, a structure that surrounds and completely seals an injector that generates fuel ejection noise and a fuel piping system that transmits vibration. For this reason, for example, there is a possibility that the fuel ejection sound leaks to the outside through a gap formed between the common rail and the head cover.

  In this case, it is conceivable that the gap formed between the common rail and the head cover is closed with, for example, a sound insulation member configured separately from the inner sound insulation member. However, an attachment member for attaching the sound insulation member is required, and the assembly process increases and the assembly operation becomes complicated.

  The present invention has been made in view of the above points, and an object thereof is to provide a soundproof structure for an internal combustion engine that can effectively suppress vibration and noise and can easily perform an assembly operation. And

In order to achieve the above-mentioned object, the present invention provides a cover body that is disposed outside the internal combustion engine body and covers at least a part of the internal combustion engine body, and a surface of the cover body that faces the internal combustion engine body. A soundproof structure for an internal combustion engine having a foamed sound insulation member made of a foamed material attached thereto, wherein the cover body is disposed at a position covering at least a high-pressure fuel injection device provided on the internal combustion engine body at a predetermined interval. Provided, at least one end side of the foamed sound insulation member with respect to the high pressure fuel injection device is provided in contact with the internal combustion engine main body, and the other end side of the foam sound insulation member with respect to the high pressure fuel injection device is provided via a high pressure fuel pipe. A high pressure fuel supply unit that supplies fuel to the high pressure fuel injection device, and a gap is provided between the high pressure fuel supply unit and the internal combustion engine body. Vignetting in the gap, the cover body and the other blowing sound insulating member made of another body is clamped, wherein the other blowing sound insulating member, a through hole is formed, the in the through hole, the high pressure fuel supply fastening members for fixing the section to the internal combustion engine body and said Rukoto is inserted.

  According to the present invention, the high-pressure fuel injection device and the high-pressure fuel supply part, which are relatively large in vibration and noise among the components of the internal combustion engine, are sound-insulated by covering the upper portion with the foam sound-insulating member, and from the high-pressure fuel injection device. By closing the gap between the high pressure fuel supply part to which vibration is transmitted via the high pressure fuel pipe and the internal combustion engine body with another foamed sound insulation member, the high pressure fuel supply part which is a vibration generation source can be enclosed. it can. As a result, according to the present invention, it is possible to avoid vibrations from being transmitted to the passenger compartment, and to effectively prevent sound leakage to the outside.

  Moreover, according to this invention, it can fix simply by pinching | interposing another foam sound-insulation member between a high pressure fuel supply part and an internal combustion engine main body. For this reason, it is possible to suppress an increase in the number of parts because a separate mounting member or the like is unnecessary, and it is possible to efficiently dispose of the components, and it is possible to improve the assembly workability with an inexpensive configuration.

Further, according to the present invention, the fastening member for fastening the high-pressure fuel supply part to the internal combustion engine body is inserted into the through-hole of the other foamed sound insulation member, so that it can be adjusted in accordance with the assembly process of the high-pressure fuel supply part. These foam sound insulation members can be assembled and fixed substantially simultaneously. For this reason, the assembly workability can be improved, other foam sound insulation members can be easily attached and detached, and replacement of new other foam sound insulation members can be easily performed. In addition, since the other foaming sound insulation member can be easily attached and detached, there is little possibility of damaging the other foamed sound insulation member during the attachment and detachment work, and it can be effectively reused.

The present invention further includes a cover body that is disposed outside the internal combustion engine body and covers at least a part of the internal combustion engine body, and a foam material attached to a surface of the cover body that faces the internal combustion engine body. A soundproof structure for an internal combustion engine having a foam sound insulation member, wherein the cover main body is disposed at a position that covers at least a high-pressure fuel injection device provided in the internal combustion engine main body at a predetermined interval, and the high-pressure fuel injection At least one end side of the foamed sound insulation member with respect to the apparatus is provided so as to contact the internal combustion engine body, and the other end side of the foamed sound insulation member with respect to the high pressure fuel injection device is connected to the high pressure fuel injection device via a high pressure fuel pipe. A high-pressure fuel supply unit that supplies fuel, and a gap is provided between the high-pressure fuel supply unit and the internal combustion engine main body; The other blowing sound insulating member consisting of the cover main body and another body is clamped, wherein the other blowing sound insulating member is cut portion is formed, the cut portion, the high pressure fuel supply to the internal combustion engine body A fastening member for fixing is inserted.

  According to the present invention, the other foamed sound insulation member can be assembled and fixed by pushing the fastening member for fastening the high pressure fuel supply part to the internal combustion engine main body along the notch formed in the other foamed sound insulation member. it can. For this reason, other foamed sound insulation members can be easily attached and detached without removing the high-pressure fuel supply section. Further, since the other foamed sound insulation member has elasticity, it can be prevented from being detached by its elastic force when the internal combustion engine is driven, and the quietness in the vehicle compartment can be ensured.

  Furthermore, according to the present invention, a projection having a locking portion at the top is provided on a surface of the cover body facing the internal combustion engine body, and a slit is formed in the foamed sound insulation member at a position corresponding to the projection. The foam sound insulation member is attached to the cover body by press-fitting the protrusion of the cover body into the slit of the foam sound insulation member.

  According to the present invention, since the foamed sound insulation member can be locked and fixed at the locking portion of the cover body, the assembly workability can be improved. Further, when the cover body is mounted on the internal combustion engine, the foamed sound insulation member is held in contact with a part of the internal combustion engine body, so that the foam sound insulation member is difficult to come off from the cover body, and the foam sound insulation member has a simple configuration. Can be securely and stably held on the cover body.

  Furthermore, the present invention has a fastened member fastened to the internal combustion engine body via a fastening member, and at least one end side of the foamed sound insulating member with respect to the high pressure fuel injection device is in contact with the fastened member It is characterized by being.

  According to the present invention, since the fastened member fastened and fixed to the internal combustion engine body via the fastening member has fastening rigidity, the fastened member itself can function as a sound insulating wall and improve sound insulation performance. The “fastened member” here corresponds to, for example, the breather chamber 28 in the embodiment of the present invention.

  Furthermore, the present invention is characterized in that the internal combustion engine book with which at least one end side of the foamed sound insulation member abuts is a breather chamber having a gas-liquid separation chamber.

  According to the present invention, the one end side of the foamed sound insulation member attached to the cover main body comes into contact with the breather chamber having the gas-liquid separation chamber, so that the cover main body can be arranged as close as possible to the internal combustion engine main body. And downsizing of the internal combustion engine body can be achieved. Further, when the gas-liquid separation chamber is extended along the crankshaft direction of the internal combustion engine body in order to ensure a predetermined capacity (volume), the contact area of the cover body can be increased and stably fixed. . Furthermore, when one end of the foamed sound insulation member comes into contact with the gas-liquid separation chamber formed with a hollow inside, for example, vibration generated in the high-pressure fuel injection device is transmitted to the gas-liquid separation chamber and resonates. It can suppress and can improve a noise suppression effect and a vibration suppression effect, respectively.

Furthermore, the present invention provides other end of the foam sound insulation member for the previous SL high-pressure fuel injection apparatus, the mounted so as to compress the high-pressure fuel supply portion abuts, the foam sound insulation abutting the high pressure fuel supply unit the side end position of the foam sound insulation member except the other end of the member surrounding the high-pressure fuel injection system, the foamed sound insulating member relative to the workpieces to be fastened to the internal combustion engine body via said fastening member compressed into abutment to said and Turkey.

  According to the present invention, the foamed sound insulation member can more reliably prevent noise from the high pressure fuel injection device from leaking to the outside, and further, by adopting a structure that surrounds the high pressure fuel injection device serving as a sound source. Further, it is possible to prevent noise and vibration leaking from the clearance between the foamed sound insulation member and the internal combustion engine body from being transmitted to the vehicle compartment side.

Further, according to the present invention, that abuts to compress the foamed sound insulating member relative to the workpieces to be fastened to the internal combustion engine main body side end position of the foamed sound insulating member, transmitted from the internal combustion engine when the internal combustion engine operation Therefore, the quietness of the entire vehicle can be improved.

  Furthermore, according to the present invention, the foamed sound insulation member itself is compressed and brought into contact with a fastened member that is fastened and fixed to the internal combustion engine body via the fastening member, so that the vibration is temporarily caused by vibration during operation of the internal combustion engine. In addition, it is possible to improve the sound insulation performance by avoiding the occurrence of a clearance between the foamed sound insulation member and the internal combustion engine body.

  It should be noted that “fastened to the internal combustion engine body via a fastening member at a side end position of the foamed sound insulation member that surrounds the high pressure fuel injection device except for the other end side of the foamed sound insulation member that is in contact with the high pressure fuel supply unit. The “fastened member” corresponds to, for example, the cylinder head 12, the cylinder head cover 14, the chain cover 16, and the like in the embodiment of the present invention.

  According to the present invention, it is possible to obtain a soundproof structure for an internal combustion engine that can effectively suppress vibration and noise and can easily perform an assembling operation.

1 is a schematic top perspective view of an internal combustion engine to which a soundproof structure according to an embodiment of the invention is applied. FIG. 2 is a schematic cross-sectional view along the longitudinal direction of the vehicle body on the upper side of the internal combustion engine shown in FIG. 1. (A) is a partially broken plan view of the engine cover as viewed from the foam sound insulation member side, (b) is a perspective view showing a protrusion provided on the cover body, and (c) is formed on the foam sound insulation member. FIG. It is a perspective view of a spacer. It is a top view of the spacer shown in FIG. It is a perspective view of the spacer concerning a modification. It is a top view of the spacer shown in FIG. It is a partial top view which shows the state by which the spacer was interposed between the common rail and the cylinder head cover. It is a fragmentary top view which shows the state in which the spacer was fixed with the stud bolt. It is a longitudinal cross-sectional view along the XX line of FIG. FIG. 10 is a longitudinal sectional view taken along line XI-XI in FIG. 9. It is a schematic cross section along the vehicle body longitudinal direction on the upper side of an internal combustion engine to which a soundproof structure according to another embodiment of the present invention is applied. It is a top view which shows the state in which the rear cover for fuel piping protection was attached via the 2nd spacer. It is a longitudinal cross-sectional view along the XIV-XIV line of FIG.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 is a top transparent schematic perspective view of an internal combustion engine to which a soundproof structure according to an embodiment of the present invention is applied, and FIG. 2 is a schematic cross-sectional view along the longitudinal direction of the vehicle body on the upper side of the internal combustion engine shown in FIG. is there. Note that “front and rear” and “up and down” indicated by arrows in each figure indicate the front and rear direction and the vertical direction of the vehicle body, and “left and right” indicate the left and right directions viewed from the driver's seat, respectively.

  The internal combustion engine 10 to which the soundproof structure according to the embodiment of the present invention is applied includes, for example, a multi-cylinder direct injection type diesel engine, and is disposed horizontally in a power plant room in the front portion of the vehicle (not shown). The internal combustion engine 10 is not limited to a diesel engine, and includes, for example, a direct injection gasoline engine.

  As shown in FIG. 1, the internal combustion engine 10 includes a cylinder head 12 coupled to an upper surface of a cylinder block (not shown), a cylinder head cover 14 (see FIG. 2) coupled to the upper surface of the cylinder head 12, a cylinder block, And a chain cover 16 coupled to the side walls of the cylinder head 12 and the cylinder head cover 14.

  These cylinder block, cylinder head 12, cylinder head cover 14 and chain cover 16 constitute an internal combustion engine body 18 as a whole. As shown in FIGS. 1 and 2, an engine cover 20 that covers a part of the upper surface of the internal combustion engine body 18 is disposed at the top of the internal combustion engine body 18. The engine cover 20 has a substantially rectangular shape in plan view, and is detachably held on the internal combustion engine body 18 by a grommet (not shown).

  As shown in FIG. 2, on the upper surface of the cylinder head 12, a plurality of injectors (high pressure fuel injection devices) 22 for injecting high pressure fuel into each cylinder (not shown), and a high pressure for each injector 22. A single common rail (high pressure fuel supply unit) 24 for supplying fuel and a fuel pipe (high pressure fuel pipe) 26 branched from the common rail 24 and connected to each injector 28 are provided.

  Further, a breather chamber 28 is disposed on the upper surface of the cylinder head cover 14 and is located on the vehicle front side that is spaced apart from the injector 22 by a predetermined distance and protrudes upward on the engine cover 20 side. The breather chamber 28 is formed of a hollow hollow body extending in the vehicle width direction, and a gas-liquid separation chamber 30 is provided therein. In the present embodiment, the breather chamber 28 and the cylinder head 12 are configured separately, but the present invention is not limited to this, and the breather chamber 28 and the cylinder head 12 may be integrally formed. Good.

  As shown in FIG. 1, the common rail 24 is formed of a substantially cylindrical column made of metal extending in the vehicle width direction, and both ends along the axial direction are cylinder heads via a pair of holders (not shown). 12 is fixed to the upper surface. Further, the common rail 24 is located on the vehicle rear side of the cylinder head 12 close to the passenger compartment in plan view.

  The engine cover 20 is made of a resin body disposed outside the internal combustion engine body 18, and covers at least a part of the internal combustion engine body 18. The internal combustion engine body 18 of the cover body 32 is formed by an inner wall of the cover body 32. And a foamed sound insulation member 34 made of a foamed material attached to a surface facing the surface.

  3A is a partially broken plan view of the engine cover as seen from the foam sound insulation member side, FIG. 3B is a perspective view showing a protrusion provided on the cover body, and FIG. It is a perspective view which shows the slit formed in the foam sound-insulation member.

  As shown in FIG. 3B, a protrusion (protrusion) 36 is integrally provided on a surface 33 (see FIG. 2) of the cover main body 32 that faces the internal combustion engine main body 18. The projecting portion 36 protrudes in a direction away from the surface 33 facing the internal combustion engine body 18, and extends in a direction orthogonal to the axis of the shaft portion 36 a provided at the top of the shaft portion 36 a. It is comprised from the meniscus-shaped latching | locking part 36b.

  On the other hand, as shown in FIG. 3C, the foamed sound insulation member 34 is formed with a linear slit 38 at a position corresponding to the protrusion 36 via a substantially circular recess 37. In this case, the foamed sound insulating member 34 is integrally attached to the cover main body 32 by press-fitting the protrusion 36 provided on the cover main body 32 into the slit 38 of the foamed sound insulating member 34 (FIG. 3A). )reference). The locking portion 36b penetrating the slit 38 locks the opposite surface 34a of the foam sound insulating member 34 facing the cover main body 32, thereby preventing the foam sound insulating member 34 from being detached from the cover main body 32. Yes. Further, as shown in FIG. 3A, the engine can be changed by changing the extending direction (direction) of the locking portions 36 of some of the plurality of protrusions 36 provided on the cover body 32. The protrusion 36 can be reliably prevented from being detached from the slit 38 due to vibration during operation.

  As shown in FIG. 2, the cover main body 32 includes a flat plate portion 32 a that is formed in a substantially flat plate shape, and a bent portion 32 b that is bent (inclined) so as to continue to the flat plate portion 32 a and fall on the vehicle rear side. And a hanging wall portion 32c that continues to the bent portion 32b and hangs downward in the vertical direction. The cover main body 32 (flat plate portion 32a) is located above the injector 22, and is provided so as to cover the upper portion of the injector 22 with a predetermined distance from the injector 22 in the vertical direction.

  Corresponding to the shape of the cover main body 32 as described above, the foamed sound insulation member 34 includes a flat plate portion 34a, a bent portion 34b, and a hanging wall portion 34c.

  One end side of the foamed sound insulation member 34 with respect to the injector 22 (the vehicle front side of the flat plate portion 34a) is provided so as to come into contact with a breather chamber 28 in which a gas-liquid separation chamber 30 is formed. Further, the other end side (lower end of the hanging wall portion 34 c) of the foamed sound insulation member 34 with respect to the injector 22 is in contact with the upper surface portion of the common rail 24 that supplies high-pressure fuel to the injector 22 through the fuel pipe 26. Is provided.

  A gap 40 is provided between the lower side of the common rail 24 and the upper surface of the cylinder head cover 14. A spacer (another foamed sound insulation member, first spacer) 42 formed separately from the cover main body 32 and the foamed sound insulation member 34 is sandwiched in the gap 40. The spacer 42 is integrally formed of the same foam material as the foamed sound insulation member 34 and is disposed so as to extend substantially parallel to the central axis of the common rail 24. In this embodiment, the spacer 42 is formed of the same foam material as that of the foamed sound insulation member 34, but may be formed of a foam material different from that of the foamed sound insulation member 34 as long as the sound insulation performance and durability are the same.

  4 is a perspective view of the spacer, FIG. 5 is a plan view of the spacer shown in FIG. 4, FIG. 6 is a perspective view of the spacer according to the modification, FIG. 7 is a plan view of the spacer shown in FIG. Is a partial plan view showing a state in which a spacer is interposed between the common rail and the cylinder head cover, FIG. 9 is a partial plan view showing a state in which the spacer is fixed with a stud bolt, and FIG. FIG. 11 is a longitudinal sectional view taken along line XI-XI in FIG. 9.

  As shown in FIGS. 4 and 5, the spacer 42 is formed with a pair of through holes 44 that penetrate substantially along the vertical direction and a plurality of curved recesses 46 that function as escapes for the fuel pipe 26 and the like. . A stud bolt (fastening member) 48 for fixing the common rail 24 to the upper surface of the cylinder head cover 14 is inserted into the through hole 44. Specifically, as shown in FIGS. 8 to 11, the fastening boss 50 attached to the common rail 24 is mounted in the through hole 44 of the spacer 42, and the screw of the stud bolt 48 passing through the fastening boss 50. The common rail 24 and the spacer 42 can be attached to the cylinder head cover 14 substantially simultaneously by screwing the portion 48 a into the screw hole 14 a of the cylinder head cover 14. In addition, the stud bolt 48 is shown as an example of a fastening member, and is not limited to this.

  The spacer 42 attached to the cylinder head cover 14 is clamped in a gap 40 formed between the cylinder head cover 14 and the common rail 24 (see FIGS. 10 and 11). Note that a curved contact surface 51 that contacts a part of the outer peripheral surface of the common rail 24 is formed on the side wall of the spacer 42 (see FIGS. 4 and 5).

  As shown in FIGS. 6 and 7, the spacer 42 a according to the modification is characterized in that a slit-like cut portion 54 that communicates from the side wall 52 of the spacer 42 a to the through hole 44 is formed. The spacer 42 a is pressed from the lateral direction, and the stud bolt 48 is pushed along the notch 54, whereby the spacer 42 a is held in the gap 40 between the common rail 24 and the cylinder head cover 14.

  The internal combustion engine 10 to which the soundproof structure according to the present embodiment is applied is basically configured as described above. Next, the function and effect will be described.

  In the present embodiment, the components 22 of the internal combustion engine 10 are insulated by covering the injector 22 and the common rail 24, which have relatively large vibration and noise, with the foamed sound insulation member 34 attached to the cover body 32, and By closing the gap 40 between the common rail 24 to which vibration is transmitted from the injector 22 via the fuel pipe 26 and the cylinder head cover 14 with a spacer 42 (spacer 42a) made of the same foam material as the foam sound insulation member 34, The common rail 24 that is a vibration generation source can be enclosed. As a result, in the present embodiment, vibrations can be prevented from being transmitted to the vehicle interior, and sound leakage to the outside can be effectively prevented.

  Moreover, in this embodiment, it can fix simply by inserting the spacer 42 (spacer 42a) between the common rail 24 and the cylinder head cover 14. FIG. For this reason, it is possible to suppress an increase in the number of parts because a separate mounting member or the like is unnecessary, and it is possible to efficiently dispose of the components, and it is possible to improve the assembly workability with an inexpensive configuration.

  Furthermore, in the present embodiment, the stud 42 is inserted into the through hole 44 formed in the spacer 42 to insert the stud bolt 48 that fastens the common rail 24 to the cylinder head cover 14, so that the spacer 42 is substantially omitted according to the assembly process of the common rail 24. It can be assembled and fixed at the same time. For this reason, the assembly workability can be improved, and the spacer 42 can be easily attached and detached via the stud bolt 48, so that a new spacer replacement work can be easily performed. Moreover, since the attaching / detaching operation of the spacer 42 is easy, the spacer 42 is less likely to be damaged during the attaching / detaching operation, and can be effectively reused.

  Furthermore, in this embodiment, the spacer 42a can be assembled and fixed by pushing the stud bolt 48 that fastens the common rail 24 to the cylinder head cover 14 along the notch 54 formed in the spacer 42a. For this reason, the spacer 42a itself can be easily attached and detached without removing the common rail 24. Further, since the spacer 42a is made of a foam material and has elasticity, it can be prevented from being detached by the elastic force when the internal combustion engine is driven, and the quietness in the vehicle compartment can be secured.

  Furthermore, in this embodiment, since the foamed sound insulation member 34 can be locked by the locking portion 36b provided in the cover body 32 and can be simply fixed, the assembly workability can be improved. Further, when the engine cover 20 is mounted on the internal combustion engine body 18, the flat plate portion 34 a on one end side and the hanging wall portion 34 c on the other end side of the foamed sound insulation member 34 are part of the internal combustion engine body 18 (the breather chamber 28 and the common rail). 24), the foamed sound insulation member 34 is not easily detached from the cover body 32, and the foamed sound insulation member 34 can be reliably and stably held on the cover body 32 with a simple configuration.

  Furthermore, in this embodiment, one end side of the foamed sound insulation member 34 attached to the cover main body 32 abuts on the breather chamber 28 having the gas-liquid separation chamber 30, so that the cover main body 32 is attached to the internal combustion engine main body 18. As a result, the internal combustion engine body 18 can be reduced in size. Further, when the gas-liquid separation chamber 30 is extended along the axial direction (crankshaft direction) of a crankshaft (not shown) of the internal combustion engine body 18 in order to ensure a predetermined capacity (volume), the contact area of the cover body 32 is increased. Can be stably fixed. Furthermore, when one end side of the foamed sound insulation member 34 comes into contact with the gas-liquid separation chamber 30 formed with a hollow inside, for example, vibration generated in the injector 22 is transmitted to the gas-liquid separation chamber 28 and resonates. And the noise suppression effect and vibration suppression effect can be improved.

  Furthermore, in this embodiment, for example, the breather chamber 28 (fastened member) fastened and fixed to the internal combustion engine body 18 via a fastening member such as a stud bolt has a fastening rigidity with respect to the internal combustion engine body 18. The breather chamber 28 itself can function as a sound insulation wall to improve sound insulation performance.

  By the way, in the present embodiment, sound leakage mainly from the periphery of the common rail 24 is achieved by the foamed sound insulation member 34 attached to the engine cover body 32 and the spacer 42 sandwiched by the gap 40 between the common rail 24 and the upper surface of the cylinder head cover 14. Adopts a structure to prevent this.

  In addition, in this embodiment, noise from the injector 22 is covered by covering the injector 22 that is a sound source and the entire common rail 24 that supplies high-pressure fuel to the injector 22 with the foamed sound insulating member 34 attached to the cover body 32. In addition to preventing leakage to the outside, it is also possible to prevent noise and vibration leaking from the clearance between the foamed sound insulation member 34 and the internal combustion engine body 18 from being transmitted to the passenger compartment side.

  Below, the enclosure structure of the injector 22 by the foam sound-insulation member 34 other than a contact position with the common rail 24 is demonstrated.

  As shown in FIG. 2, the other end side of the foamed sound insulation member 34 with respect to the injector 22 is in contact with the common rail 24, and one end side of the foamed sound insulation member 34 with respect to the injector 22 is connected to the internal combustion engine body 18 via a fastening member (not shown). The breather chamber 28 is attached to the breather chamber 28. Further, as shown in FIG. 1, a portion (side end position) corresponding to the right side surface of the internal combustion engine body 18 of the foamed sound insulation member 34 attached to the cover body 32 is compressed into a chain case (fastened member) 16. It is preferable to make it contact.

  With this configuration, it is possible to more reliably prevent noise from the injector 22 from leaking to the outside, and to further reduce vibration and noise from the chain case (chain cover 16) during engine operation. Therefore, the quietness of the entire vehicle can be improved.

  Further, on the left side surface (side end position) of the internal combustion engine main body 18 shown in FIG. 1, the cylinder head 12 (fastened member) 14 or the cylinder head 12 itself (fastened member) or the cylinder head 12 via the fastening member. It is preferable to form the foamed sound insulating member 34 so as to come into contact with another member to be fastened and fastened (for example, a shock absorbing member).

  As described above, the foamed sound insulation member 34 is formed separately from the cover main body 32 and can be easily formed according to the shape of various internal combustion engines 10 (engines). In order to fill (seal) the clearance between the engine and the internal combustion engine body 18, the sound insulation performance can be improved as compared with the conventional case.

  In addition, by enclosing the injector 22 serving as a sound source with the foamed sound insulation member 34, it is possible to prevent foreign matters such as sludge and water from entering the periphery of the injector 22, thereby improving the durability of the injector 22. be able to.

  Further, the foamed sound insulating member 34 itself is compressed and brought into contact with a member to be fastened and fixed to the internal combustion engine main body 18 via a fastening member such as a studless bolt, so that it is temporarily caused by vibration during engine operation. It is possible to improve the sound insulation performance by avoiding a clearance between the foam sound insulation member 34 and the internal combustion engine body 18.

  Next, FIG. 12 shows an internal combustion engine 10a to which a soundproof structure according to another embodiment of the present invention is applied. FIG. 12 is a schematic cross-sectional view along the longitudinal direction of the vehicle body on the upper side of an internal combustion engine to which a soundproof structure according to another embodiment of the present invention is applied. In the embodiment described below, the same components as those in the embodiment shown in FIGS. 1 to 11 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 12, in the internal combustion engine 10a to which the soundproof structure according to another embodiment is applied, the lower wall portion 32c of the cover main body 32 provided on the vehicle rear side of the engine cover 20 and the foaming in the embodiment. The difference is that the lower wall part 34c of the sound insulation member 34 is separated and configured separately, and the engine cover 20 is composed of an engine top cover 60 and an engine rear cover 62.

  By making the engine top cover 60 and the engine rear cover 62 into a divided structure, it is possible to improve vehicle mounting properties for various internal combustion engines 10 having different layouts. The mating surface 64 of the foamed sound insulation member 34b attached to the engine top cover 60 and the foamed sound insulation member 34c attached to the engine rear cover 62 is, for example, to prevent sound leakage due to manufacturing errors or assembly errors. A labyrinth structure in which the concave surface and the convex surface are integrally combined is preferable.

FIG. 13 is a plan view showing a state where the fuel pipe protecting rear cover is attached via the second spacer, and FIG. 14 is a longitudinal sectional view taken along line XIV-XIV in FIG.
As shown in FIGS. 13 and 14, a resin fuel pipe protecting rear cover 70 is provided, and a fuel supply pipe 27 (see FIG. 13) for supplying high-pressure fuel to the common rail 24 from a high-pressure pump (not shown); A second spacer 72 formed of the same foam material as that of the first spacer 42 and separate from the first spacer 42 may be interposed between the rear cover 70 for protecting the fuel pipe.

  In this way, the fuel supply pipe 27 can be protected by the second spacer 72, and the common rail 24 can be surrounded by the second spacer 72 coming into contact with the common rail 24, thereby further improving sound insulation. Can do.

  The cover body 32 itself is not fastened and fixed to the engine like the mating surface 64 of the foam sound insulation member 34b attached to the engine top cover 60 and the foam sound insulation member 34c attached to the engine rear cover 62. When both of the sound insulating members 34b and 34c have elastic force like an elastic member, if they are in contact with each other, there is no clearance even when the engine is operated. Can be improved.

10, 10a Internal combustion engine 16 Chain cover (fastened member)
18 Internal combustion engine body 20 Engine cover 22 Injector (high pressure fuel injection device)
24 common rail (high pressure fuel supply part)
26 Fuel piping 28 Breather chamber (fastened member)
30 Gas-liquid separation chamber 32 Cover body 34 Foam sound insulation member 36 Protrusion (protrusion)
36b Locking part 38 Slit 40 Gap 42, 42a Spacer (other foam sound insulation member)
44 Through hole 48 Stud bolt (fastening member)
54 Notch

Claims (6)

A cover body disposed outside the internal combustion engine body and covering at least a part of the internal combustion engine body; and a foam sound insulation member made of a foam material attached to a surface of the cover body facing the internal combustion engine body. A soundproof structure for an internal combustion engine,
The cover body is disposed at a position covering at least a high-pressure fuel injection device provided in the internal combustion engine body at a predetermined interval,
At least one end side of the foamed sound insulation member with respect to the high pressure fuel injection device is provided so as to contact the internal combustion engine body;
The other end side of the foamed sound insulation member with respect to the high pressure fuel injection device is provided so as to contact a high pressure fuel supply unit that supplies fuel to the high pressure fuel injection device via a high pressure fuel pipe,
A gap is provided between the high pressure fuel supply unit and the internal combustion engine body,
In the gap, another foamed sound insulation member formed separately from the cover body is sandwiched ,
In the other foamed sound insulation member, a through hole is formed,
Wherein the through hole is soundproof structure for an internal combustion engine, characterized in Rukoto fastening member is inserted for fixing the high pressure fuel supply to the internal combustion engine main body. A cover body disposed outside the internal combustion engine body and covering at least a part of the internal combustion engine body; and a foam sound insulation member made of a foam material attached to a surface of the cover body facing the internal combustion engine body. A soundproof structure for an internal combustion engine,
The cover body is disposed at a position covering at least a high-pressure fuel injection device provided in the internal combustion engine body at a predetermined interval,
At least one end side of the foamed sound insulation member with respect to the high pressure fuel injection device is provided so as to contact the internal combustion engine body;
The other end side of the foamed sound insulation member with respect to the high pressure fuel injection device is provided so as to contact a high pressure fuel supply unit that supplies fuel to the high pressure fuel injection device via a high pressure fuel pipe,
A gap is provided between the high pressure fuel supply unit and the internal combustion engine body,
In the gap, another foamed sound insulation member formed separately from the cover body is sandwiched,
The other foamed sound insulation member is formed with a cut portion,
A soundproof structure for an internal combustion engine, wherein a fastening member for fixing the high-pressure fuel supply unit to the internal combustion engine body is inserted into the cut portion. The soundproof structure for an internal combustion engine according to claim 1 or 2 ,
The surface of the cover body that faces the internal combustion engine body is provided with a protrusion having a locking portion at the top,
In the foamed sound insulation member, a slit is formed at a position corresponding to the protrusion,
The soundproof structure for an internal combustion engine, wherein the foamed sound insulation member is attached to the cover body by press-fitting the protrusion of the cover body into the slit of the foamed sound insulation member. The soundproof structure for an internal combustion engine according to claim 1 or 2 ,
A fastened member fastened to the internal combustion engine body via a fastening member;
The soundproof structure for an internal combustion engine, wherein at least one end side of the foamed sound insulation member with respect to the high pressure fuel injection device is in contact with the fastened member. The soundproof structure for an internal combustion engine according to claim 1 or 2 ,
The soundproof structure for an internal combustion engine, wherein the internal combustion engine body with which at least one end of the foamed sound insulation member abuts is a breather chamber having a gas-liquid separation chamber. The soundproof structure for an internal combustion engine according to claim 1 or 2,
The high end side of the foam sound insulation member for the fuel injection device is mounted so as to abut and compressed in the high pressure fuel supply,
The side end position of the foamed sound insulating member surrounding the foam sound insulation the high-pressure fuel injection device except for the other end of the member abuts on the high-pressure fuel supply portion, is fastened to the internal combustion engine body via said fastening member soundproof structure for an internal combustion engine wherein the foamed sound insulating member relative to the fastened member, wherein the benzalkonium be abutting and compressed.

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