Sound insulation cover structure for internal combustion engines

Abstract

This invention provides a sound-insulating cover structure for an internal combustion engine that allows for easy visual inspection of lubricating oil dripping from an opening. [Solution] In the sound insulation cover structure for an internal combustion engine according to the present invention, the sound insulation cover 5 is provided with a first groove 53 that is recessed vertically upward, spaced vertically away from the flange portion 4, on the vertically lower side of the pressure sensor insertion hole 150 which serves as an opening. As a result, lubricating oil that drips from the pressure sensor insertion hole 150 passes through the gap between the sound insulation cover 5 and the cylinder block 1, between the first groove 53 and the flange portion 4, and faces the outside of the sound insulation cover 5. This makes it easy to visually inspect and wipe away the lubricating oil that drips from the pressure sensor insertion hole 150.

Description

Technical Field

[0001] The present invention relates to a sound insulation cover structure for an internal combustion engine.

Background Art

[0002] As a conventional sound insulation cover structure for an internal combustion engine, for example, the one described in Patent Document 1 below is known.

[0003] In the conventional sound insulation cover structure for an internal combustion engine, a sound insulation cover capable of shielding vibrations (sound vibrations) emitted from the internal combustion engine is provided on the side of the internal combustion engine. This sound insulation cover is configured such that the upper part of the sound insulation cover contacts the cylinder head so that lubricating oil dripping from an opening (lubricating oil injection port) provided in the cylinder head cover does not flow between the outer surface of the cylinder head cover and the inner surface of the sound insulation cover (gap).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, according to the conventional sound insulation cover structure for an internal combustion engine, there is a possibility that the lubricating oil dripping from the opening (lubricating oil injection port) may enter the space (gap) between the inner surface of the sound insulation cover and the outer surface of the cylinder block. And when the lubricating oil dripping from the opening (lubricating oil injection port) enters the space (gap) between the inner surface of the sound insulation cover and the outer surface of the cylinder block, this lubricating oil is covered by the sound insulation cover, and there is still room for improvement in that the oil dripping (oil leakage) of the lubricating oil cannot be visually confirmed.

[0006] Therefore, the present invention was devised in view of the technical problems related to the conventional sound insulation cover structure for internal combustion engines, and aims to provide a sound insulation cover structure for internal combustion engines that allows for easy visual confirmation of lubricating oil dripping from the opening. [Means for solving the problem]

[0007] In one aspect, the present invention includes: an opening that opens to the outer surface of the housing of an internal combustion engine and communicates with a lubricating oil passage provided inside the housing; a sound-insulating cover attached to the outer surface of the housing and formed to avoid the opening; a flange portion provided vertically below the sound-insulating cover and at the vertical lower end of the housing, projecting laterally toward the housing; and a first groove portion provided vertically below the opening and at the vertical lower end of the sound-insulating cover, recessed vertically upward away from the flange portion and opening toward the flange portion. [Effects of the Invention]

[0008] According to the present invention, lubricating oil that drips from the opening will accumulate between the first groove and the flange through the gap between the sound insulation cover and the housing. This makes it easy to visually inspect and wipe away the lubricating oil that drips from the opening. Moreover, since the lubricating oil that drips onto the flange is wiped away, there is no risk of load being applied to the sound insulation cover, and damage to the sound insulation cover associated with the lubricating oil wiping process can be suppressed.

[0009] Furthermore, if lubricating oil drips from an opening during the manufacturing process or maintenance of an internal combustion engine, removing the lubricating oil that accumulates on the flange allows for the rapid identification of the cause of the oil dripping by investigating factors other than the manufacturing or maintenance work mentioned above, i.e., structural problems of the internal combustion engine, if an oil accumulation is subsequently discovered. [Brief explanation of the drawing]

[0010] [Figure 1]This is a perspective view of the cylinder block of the internal combustion engine according to the present invention, viewed from diagonally above the front first side. [Figure 2] This is a side view of the cylinder block of the internal combustion engine according to the present invention, as seen from the first side. [Figure 3] This is a cross-sectional view along line AA in Figure 2. [Figure 4] Figure 2 is a bottom view of the sound insulation cover, showing the inner surface of the sound insulation cover. [Figure 5] Figure 4 is a perspective view of the soundproofing cover shown, viewed from the inside and diagonally downwards. [Figure 6] This is a perspective cross-sectional view taken along line BB in Figure 2. [Modes for carrying out the invention]

[0011] The following describes in detail an embodiment of the sound-insulating cover structure for an internal combustion engine according to the present invention, based on the drawings. In this embodiment, as with the conventional, an example is given in which the sound-insulating cover structure for an internal combustion engine is applied to the cylinder block 1 of an automobile engine (spark-ignition internal combustion engine). In the description of each figure, the direction parallel to the line connecting the centers of each cylinder of the cylinder block 1 is defined as the "cylinder row direction," the direction parallel to the central axis of each cylinder is defined as the "height direction," and the direction perpendicular to the cylinder row direction and the height direction is defined as the "width direction." The top dead center side is defined as "up," and the bottom dead center side is defined as "down."

[0012] (Cylinder block configuration) Figure 1 shows a perspective view of the cylinder block 1 of the internal combustion engine according to this embodiment, viewed from diagonally above the front first side surface 13.

[0013] As shown in Figure 1, the cylinder block 1 of the internal combustion engine according to this embodiment is formed by casting a metal such as aluminum alloy or cast iron, and integrally comprises a cylinder section 2 in which a piston (not shown) is slidably housed, and a crankcase section 3 provided below the cylinder section 2 in which the upper half of a crankshaft (not shown) is rotatably housed. The cylinder section 2 has a plurality of cylinders 20 (three in this embodiment) arranged in series. The crankcase section 3 has a so-called half-skirt structure, and a plurality of bearing sections 31 that support the upper half (upper half-circumference) of the crankshaft (not shown) are provided along the cylinder row direction, which is the axial direction of the crankshaft (not shown).

[0014] Furthermore, a ladder frame (not shown), which serves as a bearing member and integrally includes multiple bearing parts that support the lower half (lower half-circumference) of the crankshaft (not shown), is attached to the lower part of the crankcase section 3. In other words, the crankcase section 3, together with the ladder frame (not shown), constitutes a single crankcase and works in cooperation with the ladder frame (not shown) to rotatably support the crankshaft (not shown). In addition, an oil pan (not shown) for storing lubricating oil (engine oil) is attached to the lower part of the ladder frame (not shown).

[0015] Furthermore, a front cover (not shown) is attached to the front end surface 11 of the cylinder block 1 to house, for example, a cam and chain (not shown), and a pulley and belt (not shown). On the other hand, a gear case (not shown) is attached to the rear end surface 12 of the cylinder block 1 to house, for example, a plurality of gear elements (not shown) that reduce and transmit the engine's output.

[0016] Furthermore, a cylinder head (not shown) is mounted on top of the cylinder block 1. An intake manifold (not shown) is connected to the first side surface 13 of the cylinder block 1 shown in Figure 2, and an exhaust pipe (not shown) is connected to the second side surface 14 of the cylinder block 1, opposite to the first side surface 13.

[0017] Also, on a first side edge portion 131 which is a lower end portion of a first side surface 13 of the cylinder block 1, a flange portion 4 in the shape of a flange protruding outward in the lateral width direction extends along the cylinder row direction along the first side edge portion 131. The flange portion 4 is configured to protrude significantly outward in the width direction beyond at least end surfaces of a pressure sensor mounting portion 15 and a knock sensor mounting portion 17 described later and also beyond a sound insulation cover 5 in the width direction. Further, a first screw insertion hole 40 penetrating perpendicularly to the flange portion 4 is provided in the flange portion 4, and by fastening a screw (not shown) inserted through the first screw insertion hole 40 to a female screw hole (not shown) provided in a ladder frame (not shown), the ladder frame (not shown) is fixed to the cylinder block 1. When adopting a configuration in which a crankshaft (not shown) is supported by a plurality of bearing members, for example, a plurality of bearing caps, the oil pan (not shown) is fixed to a lower end portion of the cylinder block 1 by fastening the screw (not shown) inserted through the first screw insertion hole 40 to a female screw hole provided in the oil pan (not shown).

[0018] Also, on the first side surface 13 of the cylinder block 1, a pressure sensor mounting portion 15 formed in a cylindrical boss shape protruding substantially perpendicularly sideward from the first side surface 13 is provided at a predetermined position on the lower end side. A pressure sensor insertion hole 150 which is an opening is provided in the pressure sensor mounting portion 15 in a penetrating state. The pressure sensor insertion hole 150 communicates with a lubricating oil passage 16 (see FIG. 3) formed inside the cylinder block 1, and a well-known hydraulic pressure sensor (not shown) is inserted into the pressure sensor insertion hole 150. This hydraulic pressure sensor (not shown) detects the pressure of the lubricating oil flowing through the lubricating oil passage 16 of the cylinder block 1.

[0019] Further, on the first side surface 13 of the cylinder block 1, a knock sensor mounting portion 17 formed in a cylindrical boss shape that protrudes substantially vertically sideward from the first side surface 13 is provided at a predetermined position on the upper end side. A knock sensor fastening hole 170, which is an opening, is provided in the knock sensor mounting portion 17 in a penetrating state. The knock sensor fastening hole 170 has an internal thread portion (not shown), and a cylindrical knock sensor 6 is attached via a bolt 72 screwed into the internal thread portion. The knock sensor 6 is a vibration sensor that detects knocking generated in the engine, has a connector 60 extending in the radial direction, and is electrically connected to an in-vehicle engine controller (not shown) via this connector 60.

[0020] Further, except for the pressure sensor mounting portion 15 and the knock sensor mounting portion 17, the first side surface 13 of the cylinder block 1 has a cover mounting portion 18 (see FIGS. 3 and 6) that is recessed in a concave shape with respect to the end surfaces of the respective sensor mounting portions 15 and 17 in a predetermined region including the peripheral portions of the pressure sensor mounting portion 15 and the knock sensor mounting portion 17. A sound insulation cover 5 capable of suppressing the vibration (acoustic vibration) of the cylinder block 1 is fitted into the cover mounting portion 18. The sound insulation cover 5 is fixed by a plurality of bolts 71 screwed into the respective internal thread holes (not shown) in a cylindrical boss shape provided in the cover mounting portion 18.

[0021] (Configuration of the sound insulation cover) FIG. 2 shows a side view seen from the side of the first side surface 13 of the cylinder block 1. FIG. 3 shows a cross-sectional view taken along the line A-A in FIG. 2. FIG. 4 shows a bottom view of the sound insulation cover 5 seen from the inside of the sound insulation cover 5 shown in FIG. 2. FIG. 5 shows a perspective view of the sound insulation cover 5 seen from the inside obliquely downward of the sound insulation cover 5 shown in FIG. 4. FIG. 6 shows a perspective cross-sectional view taken along the line B-B in FIG. 2.

[0022] For example, as shown in Figures 2 to 6, the sound insulation cover 5 is formed in a block shape using a resin material such as urethane, having a thickness corresponding to the depth of the cover mounting portion 18. The sound insulation cover 5 also has bolt insertion portions 50 formed at positions corresponding to each female screw hole (not shown), and is fixed to the cylinder block 1 via bolts 71 inserted through these bolt insertion portions 50. The outer edge of the bolt insertion portion 50 is configured as a bolt housing portion 500 recessed in a circular shape from the outer surface of the sound insulation cover 5, and the head 710 of the bolt 71 can be accommodated within this bolt housing portion 500.

[0023] Furthermore, the sound insulation cover 5 has a generally circular first notch 51 located slightly below the center and corresponding to the pressure sensor mounting portion 15, which allows the pressure sensor mounting portion 15 to face outwards. Similarly, the sound insulation cover 5 has a generally arc-shaped second notch 52 located near the upper end and corresponding to the knock sensor mounting portion 17, which allows the knock sensor mounting portion 17 to face outwards. In this way, the sound insulation cover 5 is formed (shaped) to avoid at least the pressure sensor mounting portion 15 and is attached to the outer surface of the cylinder block 1.

[0024] Furthermore, the sound insulation cover 5 is provided with a first groove 53 at its vertical lower end facing the flange portion 4 when attached to the cylinder block 1, and located vertically below the first notch 51. The groove 53 is recessed vertically upward, away from the flange portion 4. The first groove 53 functions as a window that allows lubricating oil to be seen and wiped away when, for example, lubricating oil that has dripped from the pressure sensor insertion hole 150 during the removal of the pressure sensor (not shown) during engine manufacturing or maintenance passes through the gap between the inner surface of the sound insulation cover 5 and the outer surface of the cover mounting portion 18 and reaches the flange portion 4. The first groove 53 only needs to be recessed vertically toward the side away from the flange portion 4, and its specific shape can be any shape, such as an arc shape or a rectangle shape.

[0025] Furthermore, the sound insulation cover 5 is provided with a second groove 54 that, when attached to the cylinder block 1, faces the vertical lower end of the pressure sensor mounting portion 15 and is recessed vertically downward on the side away from the pressure sensor mounting portion 15. The second groove 54 functions as a collection groove that collects lubricating oil that drips out from the pressure sensor insertion hole 150 when the pressure sensor (not shown) is removed, for example, during engine manufacturing or maintenance. The second groove 54 only needs to be recessed vertically on the side away from the pressure sensor mounting portion 15, and its specific shape can be any shape, such as an arc shape or a rectangle shape.

[0026] Here, instead of providing the second groove 54 in the sound insulation cover 5, it is also conceivable to cut out a straight line along the vertical direction from the lower vertical end of the pressure sensor mounting portion 15, so that the lower vertical end of the pressure sensor mounting portion 15 faces directly toward the flange portion 4. However, by cutting out the lower vertical end of the pressure sensor mounting portion 15 and removing the sound insulation cover 5 in this way, the sound insulation performance of the sound insulation cover 5 is reduced, and the rigidity of the sound insulation cover 5 is reduced by cutting out and separating the lower vertical end of the pressure sensor mounting portion 15, which is undesirable.

[0027] Furthermore, it is desirable that the second groove 54 is formed horizontally, approximately perpendicular to the bottom surface of the cover mounting portion 18. By forming the second groove 54 horizontally in this way, it becomes possible to collect the lubricating oil that drips from the pressure sensor insertion hole 150 in the second groove 54, which has the advantage of making it easier to visually inspect and wipe away the lubricating oil.

[0028] In addition, the second groove 54 may be formed in an inclined shape that slopes downward in the vertical direction toward the cylinder block 1 (cover mounting portion 18). By forming the second groove 54 in an inclined shape toward the cylinder block 1 (cover mounting portion 18), the lubricating oil that drips from the pressure sensor insertion hole 150 and is collected in the second groove 54 can be guided through the gap between the outer surface of the cylinder block 1 (cover mounting portion 18) and the inner surface of the sound insulation cover 5 toward the flange portion 4, which has a larger protrusion than the second groove 54. This makes it possible to accumulate more lubricating oil and has the advantage of making it easier to visually inspect and wipe away the lubricating oil through the first groove 53.

[0029] Furthermore, a third groove 55 is provided on the inner surface of the sound insulation cover 5, connecting the first groove 53 and the second groove 54. Specifically, the third groove 55 is a concave groove that is recessed in an arc shape toward the side away from the cylinder block 1 (cover mounting portion 18) and opens toward the cylinder block 1 (cover mounting portion 18), and is formed in a straight line along the vertical direction. In this way, because the third groove 55 is recessed in a concave shape relative to the cylinder block 1 (cover mounting portion 18), a connecting passage 550 with a substantially arc-shaped cross-section is formed between it and the cylinder block 1 (cover mounting portion 18), as shown in Figure 3. As a result, lubricating oil that drips from the pressure sensor insertion hole 150, or lubricating oil collected in the second groove 54, is guided to the first groove 53 via the connecting passage 550 formed by the third groove 55.

[0030] Furthermore, the sound insulation cover 5 is provided with a fourth groove 56 located on the outer peripheral edge of the knock sensor mounting portion 17. This groove is recessed in a substantially rectangular concave shape in plan view toward the side away from the knock sensor mounting portion 17 in the cylinder row direction, and recessed in a substantially rectangular concave shape in cross-section toward the side approaching the cylinder block 1 (cover mounting portion 18) in the width direction. The fourth groove 56 extends linearly in a direction perpendicular to the central axis of the knock sensor fastening hole 170, that is, along the arrangement direction of the connector 60 from which the connector 60 of the knock sensor 6 attached to the cylinder block 1 extends, and accommodates a portion of the lower end of the connector 60 of the knock sensor 6 that faces the sound insulation cover 5.

[0031] Thus, as shown in Figure 6 in particular, the fourth groove 56 is provided in the direction in which the connector 60 of the knock sensor 6 extends, that is, along the orientation of the connector 60 of the knock sensor 6 attached to the cylinder block 1, thereby enabling the person installing the knock sensor 6 to understand the orientation of the connector 60 during the installation of the knock sensor 6. Furthermore, the fourth groove 56 is recessed in a concave shape on the side approaching the cylinder block 1 (cover mounting portion 18) and accommodates a part of the lower end of the connector 60, thereby suppressing the amount of protrusion of the connector 60 that protrudes from the sound insulation cover 5.

[0032] Furthermore, the fourth groove 56 faces the vertical lower end of the knock sensor mounting portion 17 when attached to the cylinder block 1, and the vertical lower end side wall 562 facing the knock sensor mounting portion 17 is formed to rise approximately vertically from the bottom wall 561 of the fourth groove 56. This allows the lubricating oil that drips from the knock sensor fastening hole 170 to accumulate in the vertical lower end side wall 562 of the fourth groove 56, which has the advantage of making it easier to visually inspect and wipe away the lubricating oil. In addition, a bolt housing portion 500 is provided adjacent to the vertical lower end side of the fourth groove 56. This allows the lubricating oil that drips from the knock sensor fastening hole 170 to accumulate in the bolt housing portion 500 via the fourth groove 56, which has the advantage of making it easier to visually inspect and wipe away the lubricating oil.

[0033] (Effects of this embodiment) As described above, according to the sound insulation cover structure of the internal combustion engine of this embodiment, the sound insulation cover 5 is provided with a first groove 53 that is recessed vertically upward, spaced vertically below the pressure sensor insertion hole 150 which serves as an opening, and spaced vertically away from the flange portion 4. Therefore, lubricating oil that drips from the pressure sensor insertion hole 150 passes through the gap between the sound insulation cover 5 and the cylinder block 1 (cover mounting portion 18) and into the space between the first groove 53 and the flange portion 4, and faces the outside of the sound insulation cover 5. This makes it easy to visually inspect and wipe away the lubricating oil that drips from the pressure sensor insertion hole 150.

[0034] Furthermore, in this configuration, since the lubricating oil that drips onto the flange portion 4 is wiped away, there is no risk of load (pressure when wiping away the lubricating oil) being applied to the sound insulation cover 5, and damage to the sound insulation cover 5 associated with the lubricating oil wiping work can be suppressed.

[0035] Furthermore, if lubricating oil drips from the pressure sensor insertion hole 150 during the engine manufacturing process or maintenance work, removing the lubricating oil that accumulates on the flange portion 4 allows for relatively quick identification of the cause of the oil dripping by investigating factors other than the engine manufacturing or maintenance work, i.e., structural problems with the engine, if an oil accumulation is subsequently discovered.

[0036] Furthermore, in this embodiment, since the flange portion 4 protrudes more than the sound insulation cover 5 in the width direction, the allowable amount of lubricating oil that has dripped onto the flange portion 4 is increased, and the dripping of lubricating oil can be suppressed.

[0037] Furthermore, in this embodiment, the sound insulation cover 5 is provided with a second groove 54 that is recessed vertically downward at a position facing the pressure sensor insertion hole 150, which serves as an opening. This makes it possible to collect and capture lubricating oil that drips from the pressure sensor insertion hole 150 in the second groove 54. As a result, the lubricating oil that drips from the pressure sensor insertion hole 150 can be effectively visually inspected and wiped away in the second groove 54.

[0038] Furthermore, in this embodiment, a third groove 55 is provided on the inner surface of the sound insulation cover 5 facing the cylinder block 1 (cover mounting portion 18), connecting the first groove 53 and the second groove 54. This makes it possible to guide the lubricating oil that has flowed from the second groove 54 into the inside of the sound insulation cover 5 to the first groove 53. As a result, the lubricating oil that has flowed down onto the second groove 54 can flow down to the first groove 53 through the third groove 55, and the lubricating oil in the first groove 53 can be visually inspected and properly disposed of.

[0039] Furthermore, in this embodiment, the opening of the cylinder block 1 is configured as a pressure sensor insertion hole 150. Since the pressure sensor (not shown) requires insertion and removal during the manufacturing process, lubricating oil tends to drip from the pressure sensor insertion hole 150. However, by providing the first groove 53 and the second groove 54, the dripped lubricating oil can be properly disposed of.

[0040] Furthermore, in this embodiment, as described above, the pressure sensor insertion hole 150 is exemplified as the opening of the cylinder block 1. However, if the opening of the cylinder block 1 is a lubricating oil inlet, lubricating oil is likely to drip from the inlet. In this case as well, the first groove 53 and the second groove 54 are provided in the sound insulation cover 5, so that the dripping lubricating oil can be properly disposed of.

[0041] Furthermore, in this embodiment, the sound insulation cover 5 is provided with a fourth groove 56 that extends along the direction in which the connector 60 of the knock sensor 6 is facing. Therefore, the fourth groove 56 makes it possible for the person installing the knock sensor 6 to easily understand the orientation of the connector 60 during the installation of the knock sensor 6. This makes it possible to install the knock sensor 6 easily and appropriately.

[0042] Furthermore, in this embodiment, a knock sensor 6 is attached to the cylinder block 1, and the sound insulation cover 5 is provided with a fourth groove 56 that is sandwiched between the connector 60 of the knock sensor 6 and the cylinder block 1 (cover mounting portion 18), and extends along the direction pointed to by the connector 60. As a result, the orientation in which the knock sensor 6 is attached to the cylinder block 1 is specified, and the fourth groove 56 makes it possible to easily and appropriately attach the knock sensor 6, thereby improving the workability of attaching the knock sensor 6.

[0043] The present invention is not limited to the configurations illustrated in the above embodiments, and can be freely modified according to, for example, the specifications of the internal combustion engine to which the present invention is applied.

[0044] In the above embodiment, the opening according to the present invention was exemplified as a pressure sensor insertion hole 150 provided in the cylinder block 1. However, the opening according to the present invention may be, for example, a sensor insertion hole other than the pressure sensor shown, or a lubricating oil inlet. [Explanation of symbols]

[0045] 1…Cylinder block (housing) 13…First side (outer side) 150... Pressure sensor insertion hole (opening) 16...Lubricating oil passage 2...Cylinder section 3…Crankcase section 4…Flange section 5…Soundproof cover 53...First trench section 54...Second trench section 55...Third groove 56... Fourth groove 6… Knock sensor (sensor component) 60… Connector

Claims

1. An opening is provided on the outer surface of the housing of an internal combustion engine, and communicates with a lubricating oil passage located inside the housing, A sound-insulating cover is attached to the outer surface of the housing and is formed to avoid the opening, A flange portion is provided vertically below the sound insulation cover and at the vertical lower end of the housing, and protrudes laterally from the housing, A first groove is provided at the vertical lower end of the sound insulation cover, located vertically below the opening, and is recessed vertically upward, spaced apart from the flange portion, and opening toward the flange portion. A sound-insulating cover structure for an internal combustion engine.

2. A sound-insulating cover structure for an internal combustion engine according to claim 1, The flange portion protrudes more than the sound-insulating cover toward the side of the housing. Sound insulation cover structure for internal combustion engines.

3. A sound-insulating cover structure for an internal combustion engine according to claim 1 or 2, The sound-insulating cover is provided so as to face the vertical lower end of the opening and has a second groove that is recessed vertically downward away from the opening and opens toward the opening. Sound insulation cover structure for internal combustion engines.

4. A sound-insulating cover structure for an internal combustion engine according to claim 3, The sound-insulating cover is provided on the inner surface facing the housing, recessed in the vertical direction toward the side away from the housing, and has a third groove connecting the first groove and the second groove. Sound insulation cover structure for internal combustion engines.

5. A sound-insulating cover structure for an internal combustion engine according to claim 3, The aforementioned opening is an insertion hole for a pressure sensor. Sound insulation cover structure for internal combustion engines.

6. A sound-insulating cover structure for an internal combustion engine according to claim 3, The aforementioned opening is a lubricating oil inlet. Sound insulation cover structure for internal combustion engines.

7. A sound-insulating cover structure for an internal combustion engine according to claim 1, A sensor member having a connector extending along the side of the housing is attached to the housing. The sound-insulating cover is sandwiched between the connector and the housing and has a fourth groove that extends along the direction pointed by the connector. Sound insulation cover structure for internal combustion engines.

8. A sound-insulating cover structure for an internal combustion engine according to claim 7, The aforementioned sensor member is a knock sensor. Sound insulation cover structure for internal combustion engines.

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