Internal combustion engine

Abstract

The engine-side attachment bracket (6) is attached to the engine body (8) so as not to come into contact with the front cover (5) in the cylinder row direction of the engine body (8). A boss part through hole (13) of the front cover (5) is penetrated by a bolt boss part (32) of the internal combustion engine side mounting bracket (6). The second bolt boss part (32b) penetrates the boss part through hole (13a) in the front cover (5) in a manner that the outer peripheral surface does not contact with the inner peripheral surface of the boss part through hole (13a). The fifth bolt boss portion (32e) penetrates the boss portion through hole (13b) in the front cover (5) in a manner that the outer peripheral surface does not contact with the inner peripheral surface of the boss portion through hole (13b).

Description

Technical Field

[0001] The present invention relates to an internal combustion engine mounted on a vehicle. Background Art

[0002] For example, Patent Document 1 discloses a structure in which a mounting base of an engine mounting bracket is provided on an end cover that is located on one end side of an engine body and covers a camshaft drive mechanism.

[0003] However, since the vibration of the vehicle body is transmitted to the end cap of Patent Document 1 via the above-mentioned mounting base, there is a possibility that the membrane vibration will occur.

[0004] That is, the end cap of Patent Document 1 does not fully consider how to attenuate the membrane vibration itself, and there is room for further improvement in terms of attenuation of the membrane vibration.

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 7-259578 Summary of the invention

[0006] The internal combustion engine of the present invention comprises: a resin front cover which covers the end surface of one end side of the internal combustion engine body in the cylinder row direction; and a metal mounting bracket which is located at one end side of the internal combustion engine body in the cylinder row direction and mounts the internal combustion engine body to a vehicle. The mounting bracket overlaps with the front cover in the cylinder row direction of the internal combustion engine body in a manner that covers a portion of the outer surface of the front cover with a predetermined gap, and has a boss portion which penetrates a through hole formed in the front cover and is fixed to the end surface of one end side of the internal combustion engine body in the cylinder row direction. A gap is provided between the through hole and the boss portion so that the two do not contact each other.

[0007] The internal combustion engine of the present invention does not allow the engine-side mounting bracket and the front cover to contact each other, so vibration from the vehicle side (body side) is not transmitted from the engine-side mounting bracket to the front cover, and membrane vibration generated in the front cover can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is an explanatory diagram schematically showing the general structure of an internal combustion engine to which the present invention is applied.

[0009] Figure 2 This is an explanatory diagram schematically showing one end side in the cylinder bank direction of an internal combustion engine to which the present invention is applied.

[0010] Figure 3 It is a front view of the front cover.

[0011] Figure 4 It is a front view of the internal combustion engine with the internal combustion engine side mounting bracket installed.

[0012] Figure 5It is an exploded oblique view of the front cover and the mounting bracket on the internal combustion engine side.

[0013] Figure 6 This is a perspective view of the internal combustion engine side mounting bracket viewed from the back side.

[0014] Figure 7 It is an explanatory diagram schematically showing the main parts of the internal combustion engine according to the present invention. DETAILED DESCRIPTION

[0015] Hereinafter, one embodiment of the present invention will be described in detail based on the accompanying drawings. In addition, the X-axis in each figure represents the axis along the front-rear direction of the internal combustion engine 1 (the axis parallel to the central axis of the crankshaft 19 of the internal combustion engine 1), the Y-axis represents the axis along the left-right direction of the internal combustion engine 1 (the width direction of the internal combustion engine), and the Z-axis represents the axis along the up-down direction of the internal combustion engine 1 (the axis parallel to the cylinder axis A of the internal combustion engine 1). That is, the X-axis is the axis along the cylinder row direction of the internal combustion engine 1 or the internal combustion engine body 8 (described later). In addition, the Y-axis is the axis along the width direction of the internal combustion engine body 8.

[0016] Figure 1 It is an explanatory diagram schematically showing the general structure of an internal combustion engine 1 to which the present invention is applied.

[0017] The internal combustion engine 1 is, for example, a multi-cylinder internal combustion engine in series, and comprises: a cylinder head 2; a cylinder block 3 mounted on the lower portion of the cylinder head 2; a cam bracket 4 mounted on the upper portion of the cylinder head 2; a front cover 5 covering the front surface of the internal combustion engine body 8; and a metal internal combustion engine side mounting bracket 6 located on the front surface of the front cover 5. In addition, Figure 1 Reference numeral 7 in the figure is a vehicle body side mounting bracket fixed to the vehicle body side. The cylinder head 2, the cylinder block 3 and the cam carrier 4 constitute the internal combustion engine body 8. Therefore, the front cover 5 covers the end surface of the internal combustion engine body 8 on one end side in the cylinder bank direction.

[0018] The cylinder head 2 is a casting made of a metal material such as aluminum alloy, and is formed with an intake port (not shown) for supplying intake air to a combustion chamber (not shown) and an exhaust port (not shown) for discharging exhaust gas from the combustion chamber (not shown).

[0019] The cylinder block 3 is a cast product made of a metal material such as an aluminum alloy, and is formed with cylinder blocks (not shown) whose number corresponds to the number of cylinders.

[0020] The cam carrier 4 is made of a metal material such as aluminum alloy, and has a cam shaft 10 (see Figure 2 ) is supported together with the cylinder head 2 so as to be rotatable.

[0021] The front cover 5 is made of a synthetic resin material such as polyamide, and is installed in a liquid-tight manner on the internal combustion engine body 8 in such a manner as to cover the front surface of the internal combustion engine body 8. Specifically, the front cover 5 is installed on the front surface of the cylinder block 3, the front surface of the cylinder head 2, and the front surface of the cam carrier 4, etc., by bolts not shown. In other words, the front cover 5 is installed on the internal combustion engine body 8 in such a manner as to cover the end surface of the cylinder block 3 and the cylinder head 2 on one end side in the crankshaft axis direction, that is, the end surface of the internal combustion engine body 8 on one end side in the cylinder row direction.

[0022] like Figure 2 As shown, the front cover 5 has a shallow dish shape and forms a space 9 between the front cover 5 and the end surface of the engine body 8 at one end side in the cylinder bank direction, that is, the front surface of the engine body 8 . Figure 2 The diagram schematically shows one end side of the cylinder row direction of the internal combustion engine 1 in a top view. Figure 4 ) of the crankshaft sprocket (not shown), and a cam sprocket 11 fixed to the front end of the camshaft 10. A timing chain (not shown) for rotating power transmission is hung around the crankshaft sprocket and the cam sprocket 11.

[0023] An intake cam sprocket 11a and a phase variable mechanism (variable valve mechanism) 12 are mounted on the front end of the intake camshaft 10a. The phase variable mechanism 12 changes the phase of the intake valve lift center angle to change the intake valve timing. An exhaust cam sprocket 11b is mounted on the front end of the exhaust camshaft 10b.

[0024] like Figure 3 and Figure 4 As shown, the front cover 5 is formed with a boss portion through hole 13 , a crankshaft through hole 14 , a first bolt through hole 15 , and a second bolt through hole 16 . Figure 3 It is a front view of the front cover 5. Figure 4 It is a front view of the internal combustion engine 1 to which the internal combustion engine side mounting bracket 6 is mounted.

[0025] The boss through hole 13 is provided with a bolt boss 32 (see Figure 5 ) are formed at two locations in the central part of the front cover 5 in the width direction of the internal combustion engine body 8. The outer peripheral edge of the boss through hole 13 forms an annular (cylindrical) through hole peripheral edge portion (bolt through hole peripheral edge portion) 17. The through hole peripheral edge portion 17 is pressed against the end surface of one end side of the cylinder row direction of the internal combustion engine body 8 on the back side of the front cover 5 and contacts it, supporting the central part of the front cover 5 on the internal combustion engine body 8. A sealing material 18 (refer to Figure 7 ) is sealed liquid-tightly.

[0026] The boss through hole 13a is provided with a second bolt boss 32b (see Figure 5) is penetrated. A through hole peripheral edge portion 17a is formed around the boss through hole 13a. The through hole peripheral edge portion 17a is pressed against the cylinder head 2 on the back side of the front cover 5.

[0027] The boss through hole 13b is located below the boss through hole 13a and is provided for the fifth bolt boss 32e (see Figure 5 ) is penetrated. A through hole peripheral edge portion 17b is formed around the boss through hole 13b. The through hole peripheral edge portion 17b is pressed against the cylinder block 3 on the back side of the front cover 5.

[0028] The crankshaft through-hole 14 is for the crankshaft 19 to pass through, and is formed below the boss through-hole 13 .

[0029] The first bolt through holes 15 are for allowing bolts (not shown) for fixing the front cover 5 to the engine body 8 to pass therethrough, and a plurality (a plurality) of the first bolt through holes 15 are formed on the outer peripheral edge of the front cover 5 .

[0030] The second bolt through holes 16 are provided with fixing bolts 20 (see Figure 7 ) is formed on the front cover boss portion 21 adjacent to the through hole peripheral portion 17. That is, the front cover boss portion 21 is fixed to the back side of the front cover 5 in a state where its front end surface is pressed against the end surface of one end side of the cylinder row direction of the internal combustion engine body 8.

[0031] The front cover boss portion 21a is fixed to the rear side of the front cover 5 with its front end surface pressed against the cylinder head 2. The front cover boss portion 21b is fixed to the rear side of the front cover 5 with its front end surface pressed against the cylinder block 3.

[0032] The front cover boss portion 21a is formed to be continuous adjacent to the through hole peripheral portion 17a. The second bolt through hole 16a is formed in the front cover boss portion 21a. The front cover boss portion 21b is formed to be continuous adjacent to the through hole peripheral portion 17b. The second bolt through hole 16b is formed in the front cover boss portion 21b.

[0033] A crank pulley 22 is mounted on the front end of the crankshaft 19. An auxiliary machine driving belt (not shown) is wound around the crank pulley 22. The crank pulley 22 is located outside the front cover 5 and drives auxiliary machines (not shown) such as a water pump via the auxiliary machine driving belt.

[0034] The internal combustion engine side mounting bracket 6 corresponds to a mounting bracket and is mounted on an end surface of one end of the internal combustion engine body 8 in the cylinder row direction in a manner not to contact the front cover 5. The internal combustion engine side mounting bracket 6 is a casting made of a metal material such as an aluminum alloy. Figure 5 and Figure 6As shown, the engine-side mounting bracket 6 is mounted to the cylinder head 2 and the end surface of one end of the cylinder block 3 by six bolts 31, namely, the first bolt 31a to the sixth bolt 31f. The bolts 31 penetrate the bolt bosses 32 of the engine-side mounting bracket 6.

[0035] Figure 5 It is an exploded perspective view of the front cover 5 and the internal combustion engine side mounting bracket 6 mounted on the internal combustion engine body 8. Figure 6 This is a perspective view of the internal combustion engine side mounting bracket 6 as viewed from the back side (rear side).

[0036] The internal combustion engine side mounting bracket 6 is formed so that the length along the width direction of the internal combustion engine body 8 is longer than the front cover 5. Figure 2 and Figure 4 As shown, the internal combustion engine side mounting bracket 6 overlaps with the front cover 5 in the cylinder row direction of the internal combustion engine body 8 in a manner that covers a portion of the outer surface of the front cover 5 with a predetermined gap, and is mounted on the internal combustion engine body 8. That is, the internal combustion engine side mounting bracket 6 is mounted on the internal combustion engine body 8 in a manner that does not contact the front cover 5 in the cylinder row direction of the internal combustion engine body 8.

[0037] like Figures 4 to 6 As shown, the engine-side mounting bracket 6 has six bolt bosses 32, namely, the first to sixth bolt bosses 32a to 32f. The engine-side mounting bracket 6 does not contact the front cover 5, and the six bolt bosses 32 do not contact the front cover 5.

[0038] The first bolt 31a fixes the upper portion of one end side of the internal combustion engine width direction of the internal combustion engine side mounting bracket 6 to the cylinder head 2 on the outside of the front cover 5. The first bolt 31a penetrates the first bolt boss portion 32a of the internal combustion engine side mounting bracket 6. The first bolt boss portion 32a is formed on one end side of the internal combustion engine side mounting bracket 6 in the width direction of the internal combustion engine body 8.

[0039] The second bolt 31b penetrates the front cover 5 and fixes the upper portion of the engine-side mounting bracket 6, which is substantially in the center in the engine width direction, to the cylinder head 2. The second bolt 31b penetrates the second bolt boss portion 32b of the engine-side mounting bracket 6. The second bolt boss portion 32b is formed in the center portion of the engine-side mounting bracket 6 in the width direction of the engine body 8.

[0040] like Figure 7 As shown, the second bolt boss portion 32 b penetrates the boss portion through hole 13 a of the front cover 5 so that the outer peripheral surface thereof does not contact the inner peripheral surface of the boss portion through hole 13 a . Figure 71 is a cross-sectional view schematically showing the periphery of the boss through-hole 13. The front end portion of the second bolt boss portion 32b on the back side of the front cover 5 is pressed against the cylinder head 2. In addition, the portion of the through-hole peripheral edge portion 17a formed with the boss through-hole 13a, which is located on the back side of the front cover 5, is pressed against the cylinder head 2. The through-hole peripheral edge portion 17a is sealed liquid-tightly between the back side of the front cover 5 and the cylinder head 2 by an annular sealing material 18a. In addition, the front cover boss portion 21a adjacent to the boss through-hole 13a is fixed to the cylinder head 2 by the fixing bolts 20a.

[0041] The third bolt 31c fixes the upper portion of the other end side of the internal combustion engine width direction of the internal combustion engine side mounting bracket 6 to the cylinder head 2 on the outside of the front cover 5. The third bolt 31c penetrates the third bolt boss portion 32c of the internal combustion engine side mounting bracket 6. The third bolt boss portion 32c is formed on the other end side of the internal combustion engine side mounting bracket 6 in the width direction of the internal combustion engine body 8.

[0042] The fourth bolt 31d fixes the lower portion of one end side of the internal combustion engine width direction of the internal combustion engine side mounting bracket 6 to the cylinder block 3 on the outside of the front cover 5. The fourth bolt 31d penetrates the fourth bolt boss portion 32d of the internal combustion engine side mounting bracket 6. The fourth bolt boss portion 32d is formed on one end side of the internal combustion engine side mounting bracket 6 in the width direction of the internal combustion engine body 8.

[0043] The fifth bolt 31e penetrates the front cover 5 and fixes the lower portion of the engine-side mounting bracket 6, which is substantially in the center in the engine width direction, to the cylinder block 3. The fifth bolt 31e penetrates the fifth bolt boss portion 32e of the engine-side mounting bracket 6. The fifth bolt boss portion 32e is formed at the center portion of the engine-side mounting bracket 6 in the width direction of the engine body 8.

[0044] like Figure 7 As shown in FIG. 1 , the fifth bolt boss 32e penetrates the boss through hole 13b in a manner that the outer peripheral surface does not contact the inner peripheral surface of the boss through hole 13b of the front cover 5. The front end portion of the fifth bolt boss 32e on the back side of the front cover 5 is pressed against the cylinder block 3. In addition, the portion of the through hole peripheral edge portion 17b formed with the boss through hole 13b, which is located on the back side of the front cover 5, is pressed against the cylinder block 3. The through hole peripheral edge portion 17b is sealed liquid-tightly between the back side of the front cover 5 and the cylinder block 3 by an annular sealing material 18b. In addition, the front cover boss 21b adjacent to the boss through hole 13b is fixed to the cylinder block 3 by the fixing bolt 20b.

[0045] The sixth bolt 31f fixes the lower portion of the other end side of the internal combustion engine width direction of the internal combustion engine side mounting bracket 6 to the cylinder block 3 on the outside of the front cover 5. The sixth bolt 31f penetrates the sixth bolt boss portion 32f of the internal combustion engine side mounting bracket 6. The sixth bolt boss portion 32f is formed on the other end side of the internal combustion engine side mounting bracket 6 in the width direction of the internal combustion engine body 8.

[0046] like Figure 3 and Figure 4 As shown, the internal combustion engine side mounting bracket 6 has a plurality of (three) mounting portions 33. The mounting portion 33 is used to mount the internal combustion engine 1 on the vehicle body, and the upper end surface 34 is fixed to the vehicle body side mounting bracket 7 by bolts (not shown). The mounting portion 33 is formed to extend in the up-down direction, and the up-down direction is along the cylinder axis A of the internal combustion engine 1. That is, the mounting portion 33 is elongated in the up-down direction, and the upper end surface 34 thereof is fixed to the vehicle body side mounting bracket 7. The upper end surface 34 is formed to remain horizontal when the internal combustion engine 1 is mounted on the vehicle body.

[0047] The mounting portion 33 provided on the internal combustion engine side mounting bracket 6 is a first mounting portion 33a located at one end side of the internal combustion engine side mounting bracket 6 in the internal combustion engine width direction, a second mounting portion 33b located at the other end side of the internal combustion engine side mounting bracket 6 in the internal combustion engine width direction, and a third mounting portion 33c located at the center of the internal combustion engine side mounting bracket 6 in the internal combustion engine width direction. The upper end surface 34a of the first mounting portion 33a is fixed to the vehicle body side mounting bracket 7. The upper end surface 34b of the second mounting portion 33b is fixed to the vehicle body side mounting bracket 7. The upper end surface 34c of the third mounting portion 33c is fixed to the vehicle body side mounting bracket 7.

[0048] The internal combustion engine 1 of the above-mentioned embodiment has a gap provided in an annular shape over the entire circumference between the inner circumferential surface of the boss through hole 13a and the outer circumferential surface of the second bolt boss 32b so that the two (the boss through hole 13a and the second bolt boss 32b) do not contact each other. In addition, the internal combustion engine 1 has a gap provided in an annular shape over the entire circumference between the inner circumferential surface of the boss through hole 13b and the outer circumferential surface of the fifth bolt boss 32e so that the two (the boss through hole 13b and the fifth bolt boss 32e) do not contact each other. Therefore, the front cover 5 is mounted on the internal combustion engine body 8 in a state where it does not contact the internal combustion engine side mounting bracket 6 as a whole.

[0049] Thus, regarding the internal combustion engine 1 , the internal combustion engine side mounting bracket 6 and the front cover 5 do not contact each other, so that vibration from the vehicle side (body side) is not transmitted from the internal combustion engine side mounting bracket 6 to the front cover 5 , and membrane vibration generated in the front cover 5 can be suppressed.

[0050] In particular, the internal combustion engine 1 has gaps between the second bolt boss portion 32b of the internal combustion engine side mounting bracket 6 and the boss portion through hole 13a of the front cover 5, and between the fifth bolt boss portion 32e of the internal combustion engine side mounting bracket 6 and the boss portion through hole 13b of the front cover 5 so that they do not contact each other, thereby being able to suppress membrane vibration generated around the boss portion through hole 13 of the front cover 5.

[0051] The engine-side mounting bracket 6 is mounted to the engine body 8 at both ends in the width direction of the engine body 8 on the outside of the front cover 5. In addition, the second bolt boss portion 32b and the fifth bolt boss portion 32e are located approximately in the center between the two ends of the engine-side mounting bracket 6 in the width direction of the engine body 8. That is, the engine-side mounting bracket 6 is fixed to the engine body 8 at both end portions and the center portion thereof along the width direction of the engine body 8.

[0052] Therefore, the internal combustion engine 1 can stabilize the support of the internal combustion engine 1 to the vehicle.

[0053] In the internal combustion engine 1, the center portion of the front cover 5 is supported by the engine body 8 via the second bolt boss portion 32b and the fifth bolt boss portion 32e, so that the membrane vibration generated in the center of the front cover 5 (the center in the engine width direction) can be suppressed.

[0054] The internal combustion engine 1 is fixed to the internal combustion engine body 8 by the fixing bolts 20 in a state where the front cover boss portion 21 is pressed against an end surface on one end side of the internal combustion engine body 8 in the cylinder bank direction.

[0055] That is, the internal combustion engine 1 will reliably press the front cover boss portion 21 that is continuous with respect to the through hole peripheral portion 17 against the end face of one end side of the cylinder row direction of the internal combustion engine body 8, so that the sealing material 18 is reliably sandwiched between the through hole peripheral portion 17 and the end face of one end side of the cylinder row direction of the internal combustion engine body 8, thereby being able to improve the sealing performance between the through hole peripheral portion 17 and the internal combustion engine body 8.

[0056] In addition, the internal combustion engine 1 has the front cover boss portion 21 at the center of the front cover 5, so that the rigidity of the front cover 5 can be improved and the membrane vibration of the front cover 5 can be suppressed by pressing the front cover boss portion 21 against the end surface of the internal combustion engine body 8 on one end in the cylinder bank direction.

Claims

1. An internal combustion engine, wherein: The internal combustion engine has: a resin front cover that covers an end surface of the internal combustion engine body on one end side in the cylinder bank direction; and a metal mounting bracket, which is located at one end side of the cylinder row direction of the internal combustion engine body, overlaps with the front cover in the cylinder row direction of the internal combustion engine body with a predetermined gap and covers a part of the outer surface of the front cover, and mounts the internal combustion engine body to the vehicle, The mounting bracket has a boss portion that penetrates a through hole formed in the front cover and is fixed to an end surface of one end side of the internal combustion engine body in the cylinder row direction. A gap is provided between the through hole and the boss portion so that the two do not contact each other.

2. The internal combustion engine according to claim 1, wherein: The mounting bracket is formed so that the length along the width direction of the internal combustion engine body is longer than the front cover. Both ends of the mounting bracket in the width direction of the internal combustion engine body are mounted to the internal combustion engine body outside the front cover. The boss portion is located between both ends of the mounting bracket in the width direction of the internal combustion engine body.

3. The internal combustion engine according to claim 1 or 2, wherein: The front cover has an annular through-hole peripheral edge portion formed around the through-hole and pressed against an end surface on one end side of the cylinder bank direction of the internal combustion engine body. A seal is formed between the peripheral edge of the through hole and an end surface of the engine body at one end in the cylinder bank direction by an annular seal material.

4. The internal combustion engine according to claim 3, wherein: The front cover has a front cover boss portion that supports a central portion of the front cover in the width direction of the internal combustion engine body to an end surface on one end side of the cylinder row direction of the internal combustion engine body. The front cover boss portion is fixed to an end surface of the engine body at one end in the cylinder bank direction and is formed to be continuous adjacent to the peripheral edge portion of the through hole.

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