Internal combustion engine

Abstract

To suppress noise from an internal combustion engine having a cover that covers a damper.SOLUTION: A damper cover 5 of an internal combustion engine 1 has a cup portion 10 having an inner diameter corresponding to a diameter of a damper. The cup portion 10 has: an air inlet 21 for introducing air into a space within the cup portion 10; and an air outlet 22 for discharging warm air from the space within the cup portion 10 to the outside. The air outlet 22 has: a peripheral wall first opening 24 formed by cutting out a part of a peripheral wall 12 of the cup portion 10 in a window shape; and an end wall first opening 25 formed by cutting out a part of an end wall 13 of the cup portion 10 in a window shape so as to be continuous with the peripheral wall first opening 24.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an internal combustion engine having an end face covered with a cover. [Background technology]

[0002] For example, Patent Document 1 discloses an internal combustion engine in which an air inlet and an air outlet are formed in a cover that covers a disk-shaped damper attached to the crankshaft, and air is introduced into the space within the cover and exhausted from the space within the cover to cool the damper. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2022 / 219693 Summary of the Invention [Problem to be solved by the invention]

[0004] However, Patent Document 1 focuses on cooling the damper and does not take noise into consideration.

[0005] That is, in an internal combustion engine having a cover that covers a damper attached to a crankshaft, there is room for further improvement in terms of noise suppression. [Means for solving the problem]

[0006] The internal combustion engine of the present invention is provided with a cover that covers a damper, the cover having an air inlet for directing air into a space within the cover and an air outlet for discharging air from the space, the air outlet opening toward the front of the vehicle. Effect of the Invention

[0007] In the internal combustion engine of the present invention, noise leaking from the air outlet of the cover is less likely to remain behind the vehicle, and an effect of reducing noise to the outside of the vehicle can be obtained. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view of a front end portion of an internal combustion engine according to the present invention. [Diagram 2] FIG. [Diagram 3] Front view of the damper cover. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of the present invention will be described in detail below with reference to the drawings. In each drawing, the X-axis indicates an axis along the front-rear direction of the internal combustion engine 1 (an axis parallel to the central axis of the crankshaft 2 of the internal combustion engine 1), the Y-axis indicates an axis along the left-right direction (width direction of the internal combustion engine) of the internal combustion engine 1, and the Z-axis indicates an axis along the up-down direction of the internal combustion engine 1. In other words, the X-axis is an axis along the direction in which the cylinders of the internal combustion engine 1 are aligned. The Y-axis is an axis along the width direction of the internal combustion engine 1. The Z-axis is an axis along the up-down direction of the internal combustion engine 1.

[0010] 1 is a cross-sectional view of a front end portion of an internal combustion engine 1 according to the present invention. The internal combustion engine 1 is mounted, for example, in an engine room at the front of a vehicle in a so-called "horizontal" manner, with the axial direction of the crankshaft 2 perpendicular to the front-rear direction of the vehicle. In addition, the cylinder center axis of the internal combustion engine 1 is generally aligned along the vertical direction of the vehicle, and the Z axis described above is generally aligned along the vertical direction of the vehicle.

[0011] The internal combustion engine 1 has a metal chain cover 3 attached to the front end surface of a cylinder block (not shown), a disk-shaped damper 4 attached to the front end of a crankshaft 2 that passes through the chain cover 3, and a damper cover 5 attached to the front surface of the chain cover 3. The crankshaft 2 corresponds to the "rotating shaft" in the claims.

[0012] The chain cover 3 covers a valve train chain chamber (not shown) on the front end face of the cylinder block and is attached to the cylinder block with multiple bolts (not shown). In this embodiment, the cylinder block and the chain cover 3 correspond to the "engine body" in the claims.

[0013] The damper 4 has an inner peripheral member 7 fixed to the center of the front end of the crankshaft 2 with a bolt 6, a cylindrical outer peripheral member 8 having a mass required for damping action, and a cylindrical elastic member, such as a rubber member 9, interposed between the inner peripheral member 7 and the outer peripheral member 8. The damper 4 suppresses torsional vibration of the crankshaft 2.

[0014] The inner peripheral member 7 has a central boss 7a and a cylindrical rim 7b, and a rubber member 9 is firmly bonded to the outer peripheral surface of the rim 7b and the inner peripheral surface of the outer peripheral member 8.

[0015] The damper cover 5 corresponds to the "cover" in the claims, and is made of a synthetic resin material with excellent damping properties, also serving as a sound insulation cover for insulating sounds from the timing chain and the like from inside the internal combustion engine 1. The damper cover 5 is attached to the chain cover 3 in a so-called co-fastening manner by bolts for fixing the chain cover 3 to the cylinder block, for example.

[0016] As shown in Figs. 1 to 3, the damper cover 5 has a cup-shaped portion, i.e., a cup portion 10, having an inner diameter corresponding to the diameter of the damper 4, and a flat portion 11 that is placed on the outer surface of the chain cover 3 around the cup portion 10. Fig. 2 is a perspective view of the damper cover 5 alone. The cup portion 10 has a cylindrical peripheral wall portion 12 that covers the peripheral surface of the damper 4, and a flat end wall portion 13 that covers the front end surface of the damper 4. The space inside the cup portion 10 of the damper cover 5 forms a space that surrounds the entire circumference of the damper 4. The cup portion 10 has a truncated cone shape with a relatively small diameter on the end wall portion 13 side, and the inner peripheral surface 12a of the peripheral wall portion 12 that faces the peripheral surface of the damper 4 forms a tapered surface that is inclined so that the end wall portion 13 side has a relatively small diameter.

[0017] The peripheral wall 12 of the cup portion 10 molded as part of the damper cover 5 is not strictly continuous over 360°, and the lower surface side 10a of the cup portion 10 is molded to be open. In other words, when viewed from the front as shown in Fig. 3, the cup portion 10 has a horseshoe-like shape, and the lower surface side 10a does not have the peripheral wall 12. Fig. 3 is a front view of the damper cover 5.

[0018] As shown in Figures 2 and 3, the damper cover 5 has both sides of the underside 10a of the cup portion 10 formed in a stepped shape by a protruding wall portion 14 perpendicular to the flat portion 11 and a front wall portion 15 perpendicular to the protruding wall portion 14.

[0019] The chain cover 3 is formed at its lower end with a box-shaped oil tank portion 16 that protrudes forward of the internal combustion engine 1. The oil tank portion 16 forms an oil reservoir in which the space inside (on the cylinder block side) (not shown) becomes part of the chain chamber, and has a flat ceiling wall 3b that protrudes forward from the plate-shaped portion 3a of the chain cover 3, and a front wall 3c that constitutes the front surface of the oil tank portion 16. In addition to the ceiling wall 3b and the front wall 3c, the oil tank portion 16 also has a bottom wall that protrudes forward like the ceiling wall 3b, and two side walls on both sides, although these are not shown. The front wall 3c connects the bottom wall, the two side walls, and the front edges of the ceiling wall 3b.

[0020] Here, the upper surface of the ceiling wall 3b of the oil tank portion 16 is formed into a flat surface along a plane parallel to the axial direction of the crankshaft 2. The damper cover 5 has the chain cover 3 attached along the upper surface of this ceiling wall 3b.

[0021] The surface (outer surface) of the front wall 3 c of the oil tank portion 16 is formed into a flat surface along a plane perpendicular to the axial direction of the crankshaft 2 .

[0022] When the damper cover 5 is combined with the oil tank portion 16, the space inside the cup portion 10 is open to the outside through an air inlet 21 formed between the underside 10a of the cup portion 10 and the front wall 3c of the oil tank portion 16, an air outlet 22 formed by cutting out a part of the cup portion 10, and a second air outlet 23 formed by cutting out a part of the cup portion 10.

[0023] The air inlet 21 is provided to take in cooling air from the outside into the space within the cup portion 10 by utilizing a pumping action that accompanies the rotation of the damper 4 (clockwise rotation in FIG. 3).

[0024] The air outlet 22 and the second air outlet 23 are provided to exhaust warm air from the space within the cup portion 10 to the outside.

[0025] In the internal combustion engine 1, a low-pressure region is generated near the center of the damper 4 due to centrifugal force caused by the high-speed rotation of the damper 4, and air flows into the cup portion 10 from the air inlet 21. The air flowing in from the air inlet 21 is forced by the rotation of the damper 4 and swirls along the inner circumferential surface 12a of the peripheral wall portion 12 of the cup portion 10.

[0026] Here, the ease with which the air in the cup portion 10 is discharged is more influenced by the tangential force of the air flow swirling in the cup portion 10 than by the radial force of the air flow. Therefore, the air in the cup portion 10 is easily discharged in the tangential direction of the air flow.

[0027] The air inlet 21 is formed on the lower surface side 10a of the horseshoe-shaped cup portion 10, and is located outside the peripheral wall portion 12 in the radial direction of the cup portion 10. In other words, the air inlet 21 does not open in the tangential direction of the air flow (swirling flow) formed in the cup portion 10. The air outlet 22 and the second air outlet 23 are formed by cutting out a part of the cup portion 10, and open in the tangential direction of the air flow (swirling flow) formed in the cup portion 10. Therefore, when a low-pressure area occurs in the cup portion 10, air flows in from the air inlet 21, which is not open in the tangential direction of the air flow and therefore from which it is relatively difficult to discharge air, and air is discharged from the air outlet 22 and the second air outlet 23, which are open in the tangential direction of the air flow and therefore from which it is relatively easy to discharge air.

[0028] As shown in Figs. 1 to 3, the air outlet 22 has a peripheral wall first opening 24 formed by cutting out a part of the peripheral wall 12 of the cup portion 10 in the shape of a window, and an end wall first opening 25 formed by cutting out a part of the end wall 13 of the cup portion 10 in the shape of a window so as to be continuous with the peripheral wall first opening 24. In other words, the air outlet 22 is an opening that is continuous from the peripheral wall 12 to the end wall 13. The peripheral wall first opening 24 corresponds to the "front opening" in the claims, and opens toward the front of the vehicle when mounted on the vehicle. The end wall first opening 25 corresponds to the "side opening" in the claims, and opens toward the side of the vehicle when mounted on the vehicle.

[0029] As shown in FIG. 3, the air outlet 22 is formed along the 2 o'clock direction when viewed from the center position C of the cup portion 10.

[0030] 3, the air outlet 22 is formed (set) at the height of a cross member 26 and a side member 27 of the vehicle, and is entirely covered by the cross member 26 and the side member 27. That is, the peripheral wall first opening 24 is formed (set) at the height of the cross member 26, and is covered by the opposing cross member 26. The end wall first opening 25 is formed (set) at the height of the side member 27, and is covered by the opposing side member 27.

[0031] The cross member 26 corresponds to the "vehicle body component" and the "front side member" in the claims, and is, for example, a front suspension member. The cross member 26 is a member extending along the width direction of the vehicle, and is disposed in front of the internal combustion engine 1 in the vehicle front-rear direction.

[0032] In other words, the cross member 26 is a vehicle body side component other than an outer panel of the vehicle whose outer surface is exposed to the outside of the vehicle.

[0033] The side member 27 corresponds to the "vehicle body side component" in the claims. The side member 27 is a member extending along the front-rear direction of the vehicle, and is disposed on the side of the vehicle. The side member 27 is not a panel member that constitutes the outer surface of the vehicle, but a framework member that is located inside the vehicle.

[0034] In other words, the side member 27 is a vehicle body side component other than an outer panel of the vehicle whose outer surface is exposed to the outside of the vehicle.

[0035] 1 to 3, the second air outlet 23 has a second peripheral wall opening 28 formed by cutting out a part of the peripheral wall 12 of the cup part 10 in a window shape, and a second end wall opening 29 formed by cutting out a part of the end wall part 13 of the cup part 10 in a window shape so as to be continuous with the second peripheral wall opening 28. In other words, the second air outlet 23 is an opening that is continuous from the peripheral wall part 12 to the end wall part 13.

[0036] 3, the second air outlet 23 is formed along the 3 o'clock direction when viewed from the center position C of the cup part 10. In other words, the second air outlet 23 is formed at a position obtained by rotating the air outlet 22 a predetermined amount clockwise around the center position C of the cup part 10.

[0037] In the internal combustion engine 1 of the embodiment described above, the damper cover 5 has the peripheral wall first opening 24 that opens toward the front of the vehicle.

[0038] Therefore, in the internal combustion engine 1, noise leaking from the air outlet 22 of the damper cover 5 is less likely to remain behind the vehicle, and an effect of reducing noise to the outside of the vehicle can be obtained.

[0039] In addition, since the internal combustion engine 1 is mounted at the front of the vehicle on which it is mounted, noise leaking from the air outlet 22 of the damper cover 5 is not directed directly into the vehicle interior located behind the internal combustion engine 1, so that a noise reduction effect can be obtained even within the vehicle interior.

[0040] In the internal combustion engine 1, the positional relationship in the height direction (Z-axis direction) between the air outlet 22 of the damper cover 5 and the cross member 26 and the side member 27 coincides, so that noise leaking from the air outlet 22 of the damper cover 5 is blocked by the cross member 26 and the side member 27. In other words, the internal combustion engine 1 can obtain a noise reduction effect for the outside of the vehicle by blocking the noise leaking from the air outlet 22 of the damper cover 5 with the cross member 26 and the side member 27.

[0041] Although specific embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

[0042] For example, the damper cover 5 may be formed without the second air outlet 23. However, by providing the damper cover 5 with the second air outlet 23 in addition to the air outlet 22, the internal combustion engine 1 can allow a larger amount of cooling air to flow in from the air inlet 21.

[0043] For example, the air outlet 22 of the damper cover 5 may omit the peripheral wall first opening 24 and have only the end wall first opening 25 .

[0044] For example, the air outlet 22 of the damper cover 5 may omit the end wall first opening 25 and have only the peripheral wall first opening 24 .

[0045] For example, the air outlet 22 may be formed so as to be covered by a part of an outer peripheral wall 31 constituting an arch of a wheel house of the vehicle, as shown by a two-dot chain line in Fig. 3. In more detail, the air outlet 22 may be formed at a position where the end wall first opening 25 overlaps with the outer peripheral wall in a side view of the vehicle. The outer peripheral wall 31 has an arc shape in a side view of the vehicle. In this case, the internal combustion engine 1 can obtain an effect of reducing noise to the outside of the vehicle by covering the air outlet 22 with the outer peripheral wall 31. [Explanation of symbols]

[0046] 1. Internal combustion engine 2…Crankshaft 3…Chain cover 4…Damper 5…Damper cover 6…Bolt 7…Inner circumference side member 8...Outer periphery member 9...Rubber material 10…Cup section 10a…Bottom side 11...Flat area 12...Peripheral wall part 13...End wall 21…Air inlet 22...Air outlet 23…Second air outlet 24...Peripheral wall first opening 25…First opening in end wall 26…Cross member 27...Side member

Claims

1. In an internal combustion engine, a disk-shaped damper is attached to a rotating shaft protruding from an end face of an engine body, and a cover is provided to cover the damper. the cover has an air inlet for introducing air into a space within the cover by a pump action accompanying rotation of the damper, and an air outlet for discharging air from the space, The internal combustion engine, wherein the air outlet opens toward the front of the vehicle.

2. 2. The internal combustion engine according to claim 1, wherein the air outlet is set at a height position of a vehicle body component and is covered by the vehicle body component.

3. 3. The internal combustion engine according to claim 2, wherein the vehicle body component is a side member of a vehicle, and the air outlet is formed at a height position of the side member.

4. 4. The internal combustion engine according to claim 2, wherein the vehicle body component is a front member located on the vehicle front side with respect to the internal combustion engine, and the air outlet is formed at a height position of the front member.

5. the air outlet has a front opening that opens toward a front of the vehicle and a side opening that is continuous with the front opening and opens toward a side of the vehicle, the front opening is formed at a height position of a front member serving as the vehicle body component located on the vehicle front side with respect to the internal combustion engine, and is covered by the front member; 3. The internal combustion engine according to claim 2, wherein the side opening is formed at a height position of a side member of the vehicle and is covered by the side member.

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