Soundproof structure of internal combustion engine

Abstract

To provide a soundproof structure of an internal combustion engine capable of reducing noise emitted from a cylinder head to the outside and improving the assembling workability of a soundproof cover.SOLUTION: A soundproof cover 11 includes a soundproof material 12 covering a peripheral part of a head side opening part in a wall part of an end part in a cylinder-row direction in a cylinder head, and a cover member 13 attached to an 4A of the wall part so as to cover the soundproof material 12 from the outside. The cover member 13 is formed integrally with the case member 10. The case member 10 has a case-side flange part 10C surrounding the outer periphery of the case-side opening part, and a plurality of mounting parts arranged at predetermined intervals in the circumferential direction of the case-side flange part 10C, and the cover member 13 is fixed to the cylinder head only by the plurality of mounting parts.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a soundproof structure for an internal combustion engine. [Background technology]

[0002] Patent Document 1 discloses that a soundproof cover is attached to the outer surface of the internal combustion engine body in order to reduce noise emitted to the outside from the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-218890 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, an opening for allowing cooling water to flow in and out is arranged in the wall portion at the end of the cylinder row direction of the cylinder head of an internal combustion engine, and a case member having a cooling water passage formed therein and accommodating a thermostat may be attached to this opening.

[0005] However, in the conventional technology described in Patent Document 1, when the periphery of the case member is covered with a soundproof cover to reduce noise radiated from the cylinder head to the outside, an opening must be provided in the soundproof cover to allow the case member to pass through, which creates the risk of noise leaking to the outside through a gap between the case member and the soundproof cover.In addition, the mounting portion for attaching the case member and the mounting portion for attaching the soundproof cover must be located on the wall of the cylinder head, where space is limited, which creates the problem of poor workability in assembling the soundproof cover.

[0006] The present invention has been made in light of the above-mentioned circumstances, and aims to provide a soundproofing structure for an internal combustion engine that can reduce noise emitted from a cylinder head to the outside and improve the ease of assembling a soundproofing cover. [Means for solving the problem]

[0007] The present invention provides a soundproofing structure for an internal combustion engine, comprising: a head-side opening that communicates with a water jacket formed inside a cylinder head and opens into a wall portion at an end of the cylinder head in the cylinder row direction; and a case member that is fixed to the wall portion and has a case-side opening and a coolant passage portion that communicates with the head-side opening, the soundproofing structure comprising: a soundproofing cover that has soundproofing material that covers the periphery of the head-side opening in the wall portion; and a cover member that is attached to the wall portion so as to cover the soundproofing material from the outside, and the cover member is formed integrally with the case member. [Effects of the Invention]

[0008] As described above, according to the present invention, it is possible to provide a soundproofing structure for an internal combustion engine that can reduce noise radiated from the cylinder head to the outside and improve the ease of assembling the soundproofing cover. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of an internal combustion engine equipped with a soundproofing structure for an internal combustion engine according to one embodiment of the present invention. [Figure 2] FIG. 2 is a rear view of a cylinder head of an internal combustion engine equipped with a soundproof structure for an internal combustion engine according to one embodiment of the present invention. [Figure 3] FIG. 3 is a rear view of a case member of an internal combustion engine equipped with a soundproof structure for an internal combustion engine according to one embodiment of the present invention. [Figure 4] FIG. 4 is a plan view of a case member of an internal combustion engine equipped with a soundproof structure for an internal combustion engine according to one embodiment of the present invention. [Figure 5]FIG. 5 is a front view of a case member of an internal combustion engine equipped with a soundproof structure for an internal combustion engine according to one embodiment of the present invention. [Figure 6] FIG. 6 is a perspective view of a case member of an internal combustion engine equipped with a soundproofing structure for an internal combustion engine according to one embodiment of the present invention. [Figure 7] 7 is a cross-sectional view taken along the arrows VII-VII of the internal combustion engine equipped with the soundproofing structure for an internal combustion engine shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] According to one embodiment of the present invention, there is provided a soundproofing structure for an internal combustion engine, the soundproofing structure including: a water jacket formed inside the cylinder head; a head-side opening communicating with the water jacket and opening into a wall portion of the cylinder head at an end in the direction of cylinder alignment; a case member fixed to the wall portion, the case member having a case-side opening communicating with the head-side opening and a coolant passage; and a soundproofing cover including a soundproofing material covering a periphery of the head-side opening in the wall portion; and a cover member attached to the wall portion so as to cover the soundproofing material from the outside, the cover member being formed integrally with the case member. As a result, the soundproofing structure for an internal combustion engine according to the one embodiment of the present invention can reduce noise radiated from the cylinder head to the outside and can improve the ease of assembling the soundproofing cover. [Example]

[0011] A soundproofing structure for an internal combustion engine according to one embodiment of the present invention will be described below with reference to the drawings. Figures 1 to 7 are views showing a soundproofing structure for an internal combustion engine according to one embodiment of the present invention. In Figures 1 to 7, the up / down, front / rear, left / right directions refer to the front / rear direction of the vehicle, the left / right direction of the vehicle (vehicle width direction) and the up / down direction of the vehicle (vehicle height direction).

[0012] First, the configuration will be explained. In Fig. 1, an internal combustion engine 1 has an internal combustion engine body 2. The internal combustion engine body 2 has a cylinder block 5, a cylinder head 4 arranged on top of the cylinder block 5, and a head cover 3 arranged on top of the cylinder head 4. The internal combustion engine body 2 also has an oil pan (not shown) that stores oil, and the oil pan is arranged below the cylinder block 5.

[0013] In Fig. 1, a wall portion 4A is provided at the end of the cylinder head 4 in the cylinder row direction (front-rear direction). The wall portion 4A forms a side wall surface at the rear end of the cylinder head 4. In Fig. 7, a water jacket 4G through which cooling water flows is formed inside the cylinder head 4.

[0014] 2, a head-side opening 4E is formed in the wall portion 4A. The head-side opening 4E communicates with a water jacket 4G (see FIG. 7) formed inside the cylinder head 4.

[0015] 1 and 3, a case member 10 is fixed to a wall portion 4A of the cylinder head 4. In FIG. 5, a case-side opening 10A that communicates with a head-side opening 4E is formed in the case member 10. In FIG. 6, a coolant passage portion 10B is formed in the case member 10. Coolant in the cylinder head 4 flows in and out through the coolant passage portion 10 of the case member 10. A thermostat (not shown) is housed in the coolant passage portion 10B.

[0016] 1 and 4, the internal combustion engine 1 is provided with a soundproof cover 11. The soundproof cover 11 has a soundproof material 12 that covers the periphery of the head-side opening 4E in the wall portion 4A, and a cover member 13 that is attached to the wall portion 4A so as to cover the soundproof material 12 from the outside.

[0017] The cover member 13 functions as a covering that covers the soundproofing material 12 from the outside so that the soundproofing material 12 is in close contact with the wall portion 4A of the cylinder head 4. The cover member 13 is formed integrally with the case member 10. More specifically, the case member 10 and the cover member 13 are formed integrally from resin. The soundproofing material 12 is fixed to the cover member 13 by a method such as adhesion.

[0018] 5, the case member 10 has a case flange 10C that surrounds the outer periphery of the case opening 10A, and a plurality of mounting portions 10D that are arranged at predetermined intervals around the circumferential direction of the case flange 10C. The case flange 10C is provided on the inner surface of the case member 10 (the surface facing the wall 4A of the cylinder head 4). The cover member 13 is fixed to the cylinder head 4 only by the plurality of mounting portions 10D.

[0019] In other words, the cover member 13 does not have a dedicated attachment portion for fixing the cover member 13 to the cylinder head 4, but is fixed to the cylinder head 4 only by the attachment portion 10D of the case member 10 formed integrally with the cover member 13. Therefore, when the case member 10 is fixed to the cylinder head 4, the cover member 13 is also fixed to the cylinder head 4.

[0020] 1 and 6, the cylinder head 4 has an exhaust side wall 4B that extends in a direction (front-rear direction) intersecting the wall portion 4A and to which the exhaust device 6 is attached. This exhaust side wall 4B is a wall portion on the left side surface of the cylinder head 4. The exhaust device 6 consists of an exhaust pipe and a heat insulating cover.

[0021] The cover member 13 has a planar rear wall 13A that extends parallel to the wall 4A. The rear wall 13A is continuous with the case member 10. A bent portion 13B is formed at the edge of the cover member 13 on the side (left side) adjacent to the exhaust side wall 4B, and is bent toward the wall 4A to cover the outer periphery of the soundproofing material 12. The bent portion 13B is provided at the left edge of the rear wall 13A and extends forward from this edge.

[0022] A bottom wall 13C is provided below the rear wall 13A of the cover member 13. The bottom wall 13C extends toward the wall portion 4A (forward) so as to approach the rear wall 13A as it extends downward. The bottom wall 13C also covers the outer periphery of the soundproofing material 12. Therefore, the left end of the soundproofing material 12 is covered by the folded portion 13B of the cover member 13, and the bottom end of the soundproofing material 12 is covered by the bottom wall 13C of the cover member 13.

[0023] A recess 13E is formed in the upper part of the rear wall 13A of the cover member 13. The recess 13E is formed to avoid interference with a pipe (not shown) connected to the case member 10.

[0024] In Fig. 2, the cylinder head 4 has a head-side flange 4C that is joined to the case-side flange 10C. The head-side flange 4C surrounds the outer periphery of a head-side opening 4E. The cylinder head 4 has a plurality of mounting portions 4D that are arranged at predetermined intervals around the circumferential direction of the head-side flange 4C. As shown in Fig. 3, bolts 10E inserted into the mounting portions 10D of the case member 10 are screwed into these mounting portions 4D.

[0025] 7, the cylinder head 4 has a recess 4F. The recess 4F is a recessed portion along the outer periphery of the head-side flange 4C (FIG. 2). On the other hand, the soundproofing material 12 has a protrusion 12A that is inserted into the recess 4F.

[0026] As described above, this embodiment is provided with a soundproof cover 11 having soundproof material 12 that covers the peripheral portion of the head-side opening 4E in the wall portion 4A and a cover member 13 that is attached to the wall portion 4A so as to cover the soundproof material 12 from the outside, and the cover member 13 is formed integrally with the case member 10.

[0027] As a result, by integrating the soundproof cover 11 with the case member 10 having the coolant passage portion 10B, no gap is created between the soundproof cover 11 and the case member 10, thereby reducing noise radiated to the outside from the cylinder head 4. Furthermore, by fixing the case member 10 to the wall portion 4A of the cylinder head 4, the soundproof cover 11 integrated with the case member 10 can be attached to the cylinder head 4 via the case member 10. This reduces the number of fixing points of the soundproof cover 11 to the cylinder head 4, improving the ease of assembling the soundproof cover 11. As a result, noise radiated to the outside from the cylinder head 4 can be reduced, and the ease of assembling the soundproof cover 11 can be improved.

[0028] In addition, in this embodiment, the case member 10 has a case side flange portion 10C that surrounds the outer periphery of the case side opening 10A and a plurality of mounting portions 10D that are arranged at predetermined intervals around the circumferential direction of the case side flange portion 10C, and the cover member 13 is fixed to the cylinder head 4 only by the plurality of mounting portions 10D.

[0029] As a result, the only place where the integrally formed case member 10 and cover member 13 are attached to the cylinder head 4 is the attachment portion 10D, and no attachment portion other than the attachment portion 10D is required, thereby improving the ease of assembling the case member 10 and cover member 13 to the wall portion 4A.

[0030] In addition, in this embodiment, the cylinder head 4 has an exhaust side wall 4B that extends in a direction intersecting the wall portion 4A and to which the exhaust device 6 is attached, and a folded portion 13B is formed at the edge of the cover member 13 on the side adjacent to the exhaust side wall 4B, which is folded toward the wall portion 4A and covers the outer periphery of the soundproofing material 12.

[0031] As a result, the soundproofing material 12 can be protected from the heat of the exhaust device 6 by the bent portion 13B of the cover member 13.

[0032] In addition, in this embodiment, the cylinder head 4 has a head side flange portion 4C that is joined to the case side flange portion 10C, and a recess 4F that is a recess along the outer periphery of the head side flange portion 4C, and the soundproofing material 12 has a protrusion 12A that is inserted into the recess 4F.

[0033] As a result, the walls of the recess 4F are cooled by the cooling water flowing through the water jacket 4G, and therefore, by inserting the protrusion 12A of the soundproofing material 12 into this recess 4F, heat from the soundproofing material 12 can be released, thereby suppressing excessive temperature rise of the soundproofing material 12. Furthermore, by inserting the protrusion 12A of the soundproofing material 12 into the recess 4F of the cylinder head 4, it is possible to suppress the occurrence of a gap between the cylinder head 4 and the soundproofing material 12, thereby improving soundproofing performance.

[0034] While an embodiment of the present invention has been disclosed, it will be apparent to one skilled in the art that modifications may be made thereto without departing from the scope of the present invention, and it is intended that all such modifications and equivalents be included in the following claims. [Explanation of symbols]

[0035] 1. Internal combustion engine 2 Internal combustion engine body 4. Cylinder head 4A Wall 4B Exhaust side wall 4C Head flange 4E Head side opening 4F Recess 4G Water Jacket 6. Exhaust system 10 Case material 10A Case side opening 10B Cooling water passage section 10C Case side flange 10D Mounting part 11 Soundproof cover 12 Soundproofing materials 12A Convex part 13 Cover member 13B Bending part

Claims

1. a head-side opening communicating with a water jacket formed inside the cylinder head and opening in a wall portion at an end of the cylinder head in the cylinder row direction; a case member fixed to the wall portion, the case member having a case-side opening communicating with the head-side opening and a coolant passage portion, a soundproof cover including a soundproof material that covers a peripheral portion of the head-side opening in the wall portion, and a cover member that is attached to the wall portion so as to cover the soundproof material from the outside, 10. A soundproofing structure for an internal combustion engine, wherein the cover member is formed integrally with the case member.

2. the case member has a case-side flange portion surrounding an outer periphery of the case-side opening, and a plurality of attachment portions arranged at predetermined intervals in a circumferential direction of the case-side flange portion, 2. The soundproofing structure for an internal combustion engine according to claim 1, wherein the cover member is fixed to the cylinder head only by the plurality of mounting portions.

3. the cylinder head has an exhaust side wall extending in a direction intersecting the wall portion and to which an exhaust device is attached, 3. A soundproofing structure for an internal combustion engine according to claim 1, wherein a bent portion is formed at the edge of the cover member adjacent to the exhaust side wall so as to approach the wall portion and cover the outer periphery of the soundproofing material.

4. the cylinder head has a head-side flange portion joined to the case-side flange portion, and a recess formed by recessing a portion along the outer periphery of the head-side flange portion, 3. The soundproof structure for an internal combustion engine according to claim 2, wherein the soundproof material has a protrusion that is inserted into the recess.

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