JP2015140729A - Internal combustion engine - Google Patents

Abstract

An internal combustion engine capable of maintaining the effect of suppressing noise (radiated sound) caused by vibration of an internal combustion engine body over a long period of time.
An engine 100 (internal combustion engine) is arranged on a side opposite to an engine body 10 of a TCC 20 and a timing chain cover (TCC) 20 attached to an engine body 10 having a crankshaft 40, and an oil seal 5 is provided. And an aluminum alloy retainer 50 for fixing. The TCC 20 is provided in a circumferential shape so as to surround the region S in which the retainer 50 and the TCC 20 overlap each other when viewed from the X direction in which the crankshaft 40 extends, and the retainer 50 and the TCC 20 protrude in the direction of the arrow X2 facing each other. A wall 26 is included.
[Selection] Figure 2

Description

  The present invention relates to an internal combustion engine, and more particularly, to an internal combustion engine including a cover member attached to an internal combustion engine body and an oil seal fixing member for fixing an oil seal attached to a crankshaft.

  2. Description of the Related Art Conventionally, an internal combustion engine including a cover member attached to an internal combustion engine main body and an oil seal fixing member for fixing an oil seal attached to a crankshaft is known (for example, see Patent Document 1).

  Patent Document 1 discloses an engine (internal combustion engine) including a cam chain cover (cover member) attached to a cylinder block (internal combustion engine body) and a vibration control plate attached to the front surface of the cam chain cover. ing. In the engine described in Patent Document 1, the damping plate is crimped by rivets in a state where three thin steel plates having a predetermined thickness are stacked. And the damping plate with which the three steel plates were integrated is being fixed to the cam chain cover via the sealing material. As a result, when the vibration of the engine body is transmitted to the cam chain cover, the vibration energy of the cam chain cover is converted into friction energy (thermal energy) at the contact surface between the steel plates in the vibration control plate, so that the cam chain cover Is configured to be damped. Further, since the vibration of the cam chain cover is attenuated by the vibration control plate, the radiated sound caused by the vibration of the engine body from the cam chain cover is also suppressed.

JP 2008-106809 A

  However, in the engine (internal combustion engine) described in Patent Document 1, vibration energy on the cam chain cover side is converted into friction energy (thermal energy) using friction between steel plates in the vibration control plate. May be used over a long period of time, the friction surface between the steel plates may be worn or the steel plates may be welded due to frictional heat. If such mechanical alteration occurs in the damping plate over time, the conversion efficiency from vibration energy to friction (thermal) energy will decrease, and the performance inherent in the damping plate (reducing vibration of the cam chain cover) Effect) decreases. In addition, since the performance deterioration progresses in the direction in which the vibration reduction effect decreases, noise (radiated sound) from the cam chain cover (cover member) that vibrates together with the engine body (internal combustion engine body) without vibration being reduced is less likely to be suppressed. . For this reason, there exists a problem that the suppression effect of the noise resulting from the vibration of an internal combustion engine main body cannot be maintained over a long period of time.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to maintain the effect of suppressing noise (radiated sound) caused by vibration of the internal combustion engine body over a long period of time. It is an object of the present invention to provide an internal combustion engine.

  In order to achieve the above object, an internal combustion engine according to one aspect of the present invention is disposed on a side of an internal combustion engine body having a crankshaft, which is attached to the side of the internal combustion engine body, and on the opposite side of the internal combustion engine body of the cover member. An oil seal fixing member for fixing an oil seal mounted on the crankshaft, and at least one of the oil seal fixing member and the cover member is provided with an oil seal fixing member and a cover member when viewed from the direction in which the crankshaft extends. A circumferential wall is provided so as to surround regions that overlap each other, and includes a circumferential wall that protrudes in a first direction in which the oil seal fixing member and the cover member face each other.

  In the internal combustion engine according to one aspect of the present invention, as described above, at least one of the oil seal fixing member and the cover member surrounds a region where the oil seal fixing member and the cover member overlap each other when viewed from the direction in which the crankshaft extends. A circumferential shape surrounding the region where the oil seal fixing member and the cover member overlap each other by providing circumferential walls that protrude in the first direction opposite to each other and are provided circumferentially. Noise caused by vibration of the internal combustion engine body that is caused by the turning operation of the crankshaft due to the wall, especially noise caused by vibration of the valve timing system inside the cover member and in the vicinity of the crankshaft ( (Such as the operation sound during the meshing operation of the timing chain and sprocket) It is possible to enclose the inside of Jo wall. That is, the circumferential wall provided in the circumferential shape can prevent the noise (radiated sound) of the internal combustion engine body from leaking out (difficult to diffuse) to the outside. In this case, for example, unlike the case where the vibration energy of the cover member that vibrates together with the internal combustion engine body is converted into friction energy (thermal energy) to reduce the vibration of the cover member and the associated noise, Since a configuration is used in which the noise of the internal combustion engine body is enclosed inside the peripheral wall using a peripheral wall that does not cause mechanical deterioration over time, the noise reduction effect deteriorates (decreases) over time. There is nothing. As a result, the effect of suppressing noise caused by the vibration of the internal combustion engine body can be maintained for a long time.

  In the internal combustion engine according to the above aspect, the rigidity of the oil seal fixing member and the cover member can be improved by providing a circumferential wall on at least one of the oil seal fixing member and the cover member. The vibration of the internal combustion engine body can be suppressed from being significantly transmitted to the oil seal fixing member and the cover member. This also prevents noise (radiated sound) from diffusing from the internal combustion engine body due to the vibration of the oil seal fixing member and the cover member accompanying the vibration of the internal combustion engine body without being affected by the long-term use of the internal combustion engine. ) The level itself can be reduced.

  In the internal combustion engine according to the above aspect, preferably, the space between the oil seal fixing member and the cover member surrounded by the circumferential wall constitutes a Helmholtz resonance portion, and the tip of the circumferential wall and the circumferential wall By adjusting the size of the gap between at least one of the opposing surfaces of the oil seal fixing member and the cover member, which are opposed to each other, the predetermined resonance frequency is set. If comprised in this way, the space used as a Helmholtz resonance part can be easily formed between an oil seal fixing member and a cover member by surrounding a surrounding wall. Then, the size of the gap (circumferential wall) at the entrance of the space as the Helmholtz resonance part so that the Helmholtz resonance part has a resonance frequency (for example, a frequency at which the radiated sound has a maximum value and its vicinity) that exhibits a silencing effect. Space between the oil seal fixing member and the cover member surrounded by the circumferential wall (Helmholtz resonance). Part) can effectively cancel out a specific frequency band (frequency at which the radiated sound is the maximum value and its vicinity) among the noise (radiated sound) resulting from the vibration of the internal combustion engine body. At this time, since the tip of the circumferential wall is not in contact with the opposing surface through a gap, there is no friction between the oil seal fixing member and the cover member (circumferential wall), and the spatial shape as the Helmholtz resonance part Is maintained. As a result, in addition to reducing noise by converting the vibration energy of the internal combustion engine body into friction energy, etc., in addition to the effect of suppressing the continuous diffusion of noise due to the peripheral wall that does not cause mechanical deterioration over time, Even with the space that continues to function as the Helmholtz resonance unit, the noise (radiated sound) level itself caused by the vibration of the internal combustion engine body can be effectively reduced. In the present invention, “the size of the gap” means the tip of the circumferential wall and the oil seal fixing member or the cover facing the tip of the circumferential wall in one section in a state where the oil seal fixing member and the cover member are arranged to face each other. Not only the gap length with the opposing surface of the member, but also this gap length has a wide meaning extending to the circumference when surrounding the space (Helmholtz resonance part) circumferentially along the circumferential wall. That is, the volume between the tip of the circumferential wall and the facing surface facing it (the product of the tip wall width, the facing interval (gap length) and the circumference), and the spatial volume (the Helmholtz resonance part). This is because Helmholtz resonance occurs based on the ratio to the volume.

  In the internal combustion engine according to the above aspect, the circumferential wall preferably has a first circumferential wall extending from the oil seal fixing member toward the cover member, and a first direction in which the crankshaft extends with respect to the first circumferential wall. And a second circumferential wall that is disposed so as to be opposed to each other with a predetermined interval in a second direction perpendicular to the first wall and extends from the cover member toward the oil seal fixing member. With this configuration, it is possible to form a circumferential wall in which either the first circumferential wall or the second circumferential wall surrounds the other from the outside in a plan view. That is, by the circumferential wall having at least a double structure of the first circumferential wall extending from the oil seal fixing member toward the cover member and the second circumferential wall extending from the cover member toward the oil seal fixing member, A maze structure (sound insulation structure) can be formed in a circumferential shape in a region near the outer edge of the space between the oil seal fixing member and the cover member. Thereby, it is possible to further suppress leakage of noise generated inside the cover member due to vibration of the internal combustion engine body to the outside of the internal combustion engine body.

  The internal combustion engine according to the one aspect described above preferably further includes a sound absorbing material provided in a space between the oil seal fixing member and the cover member surrounded by the circumferential wall. If comprised in this way, the noise (radiated sound) accompanying the vibration of the internal combustion engine main body can be absorbed also by the sound absorbing material in the space between the oil seal fixing member and the cover member surrounded by the circumferential wall. . Accordingly, in this case as well, in addition to the continuous noise suppression effect by the peripheral wall that does not cause mechanical deterioration over time, the noise reduction effect can be continuously obtained by the sound absorbing material that absorbs noise. . As a result, noise (radiated sound) resulting from the vibration of the internal combustion engine body can be more effectively suppressed.

  In the internal combustion engine according to the above aspect, the internal combustion engine body preferably includes a timing chain and a sprocket, and is disposed between the oil seal fixing member and the cover member surrounded by the circumferential wall when viewed from the direction in which the crankshaft extends. The space is arranged so as to overlap the meshing portion between the timing chain and the sprocket. If comprised in this way, the meshing part with which the timing chain and sprocket which become one of the noise sources of an internal combustion engine main body mesh | engage easily is surrounded by the surrounding wall provided in the periphery seeing from the direction where a crankshaft is extended. be able to. Therefore, it is possible to effectively suppress the noise radiated (diffused) from the meshing portion from passing through the space where the cover member and the oil seal fixing member overlap and diffusing outside.

  In the internal combustion engine according to the above aspect, at least one of the cover member and the oil seal fixing member is preferably made of resin. If comprised in this way, by making at least any one of a cover member and an oil seal fixing member into a resin member, it becomes easy to improve the sound absorption property with respect to the noise diffused from an internal combustion engine main body compared with a metal member etc. it can.

  In the present application, the following configuration is also conceivable in the internal combustion engine according to the above aspect.

(Additional item 1)
That is, in the internal combustion engine according to the first aspect, the cover member is made of resin, and the oil seal fixing member is made of metal. With this configuration, the cover member is made of resin for the purpose of reducing the weight of the internal combustion engine, and the oil seal fixing member is made of metal for the purpose of attaching the oil seal to the crankshaft with high accuracy. Even if it exists, the noise reduction effect (continuous reduction effect of the radiated sound resulting from the vibration of an internal combustion engine main body) in an internal combustion engine main body can be effectively and easily acquired by the circumferential wall provided in the periphery.

(Appendix 2)
In the internal combustion engine according to the above aspect, the circumferential wall is provided so as to surround the crankshaft and the oil seal when viewed from the direction in which the crankshaft extends. With this configuration, even if the crankshaft end extends from the portion where the oil seal is mounted to the outside of the cover member, the circumferential wall is provided so as to surround the crankshaft and the oil seal. It is possible to effectively suppress the noise of the engine body from diffusing from the vicinity of the penetration portion of the cover member to the outside.

  ADVANTAGE OF THE INVENTION According to this invention, the internal combustion engine which can maintain the suppression effect of the noise (radiation sound) resulting from the vibration of an internal combustion engine main body over a long period of time as mentioned above can be provided.

1 is a perspective view showing a schematic configuration of an engine according to a first embodiment of the present invention. It is the side view which looked at the engine by a 1st embodiment of the present invention from the front end side of a crankshaft. It is the top view which looked at the chain cover single-piece | unit in the engine by 1st Embodiment of this invention from the outer side. In the engine by a 1st embodiment of the present invention, it is a top view which looked at the retainer holding an oil seal from the back side (side attached to an engine body). FIG. 5 is a cross-sectional view taken along line 150-150 in FIG. In the engine by 2nd Embodiment of this invention, it is the top view which looked at the retainer holding an oil seal from the back surface side (side attached to an engine main body). In the engine by 2nd Embodiment of this invention, it is sectional drawing which showed the state with which the timing chain cover and the retainer were assembled | attached to the engine main body. In the engine by 3rd Embodiment of this invention, it is sectional drawing which showed the state with which the timing chain cover and the retainer were assembled | attached to the engine main body. In the engine by 3rd Embodiment of this invention, it is a side view for demonstrating the arrangement | positioning state of the sound-absorbing material between a timing chain cover and a retainer. In the engine by 4th Embodiment of this invention, it is sectional drawing which showed the state with which the timing chain cover and the retainer were assembled | attached to the engine main body. In the engine by 4th Embodiment of this invention, it is a side view for demonstrating the arrangement | positioning state of the sound-absorbing material between a timing chain cover and a retainer.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
First, the configuration of the engine 100 according to the first embodiment of the present invention will be described with reference to FIGS. In the following description, the direction in which the crankshaft 40 extends in the engine 100 is defined as the X direction, the direction perpendicular to the crankshaft 40 in the horizontal plane is defined as the Y direction, and the vertical direction in which the cylinder 2a extends is defined as the Z direction. The engine 100 is an example of the “internal combustion engine” in the present invention.

  As shown in FIG. 1, an automobile engine 100 according to a first embodiment of the present invention includes an engine body 10 including an aluminum alloy cylinder head 1, a cylinder block 2, and a crankcase 3. An engine 100 made of a gasoline engine is assembled with a side end portion (edge portion 2b) on the X2 side of the engine body 10 and a resin timing chain cover 20 (hereinafter referred to as TCC 20) covering the timing chain 4. And a head cover 30 assembled on the upper side (Z1 side) of the cylinder head 1. The engine body 10 is an example of the “internal combustion engine body” in the present invention. The timing chain cover (TCC) 20 is an example of the “cover member” in the present invention.

  Inside the cylinder head 1, a camshaft 45 (shown by a broken line) and a valve mechanism (details not shown) constituting a valve operating timing member are arranged. A cylinder 2a (shown by a broken line) in which a piston 11 (shown by a broken line) reciprocates in the Z direction is formed inside the cylinder block 2 connected to the lower side (Z2 side) of the cylinder head 1. The cylinder head 1 is connected to an intake device (not shown) that introduces intake air into each of a plurality (four) of cylinders 2 a formed in the cylinder block 2.

  A crank chamber 3 a is formed at the inner bottom of the engine body 10 by the cylinder block 2 and the crankcase 3 connected to the lower side (Z2 side) of the cylinder block 2. A crankshaft 40 that is rotatably connected via a piston 11 and a connecting rod (not shown) is disposed in the crank chamber 3a. In FIG. 1, the crankshaft 40 is illustrated in a substantially rod shape. However, in actuality, the crankshaft 40 has a balance between the crankpin with the rotating shaft being eccentric and the crankpin sandwiched immediately below each cylinder 2a. A weight is connected to the crank journal.

  An oil reservoir 3b for accumulating engine oil (hereinafter simply referred to as oil) is provided at the lower portion (Z2 side) of the crank chamber 3a. The oil is pumped up from the oil reservoir 3b to the upper part in the engine body 10 by an oil pump (not shown) and supplied to a sliding part such as a valve timing system including the camshaft 45 and the outer peripheral surface of the piston 11. Then, it is dropped (dropped) by its own weight and returned to the oil reservoir 3b.

  As shown in FIG. 2, the TCC 20 has a planar shape that overlaps the side cross-sectional shape on the X2 side of the engine body 10 (see FIG. 1). Further, the TCC 20 has a main body portion 21 that swells toward the front side of the paper (in the direction of the arrow X2), and a boss portion that has a through hole 22a on the lower side (Z2 side) of the main body portion 21 and in the vicinity of the center portion in the Y direction. 22 (see FIG. 3) is formed. The through hole 22a penetrates the main body portion 21 in the thickness direction, and is configured such that the front end portion 40a (see FIG. 1) of the crankshaft 40 is inserted into the through hole 22a.

  Further, the TCC 20 has a pair of end portions 23 arranged in opposite directions (arrow Y1 direction and arrow Y2 direction) around the through hole 22a. Further, each end portion 23 formed in a flange shape is formed with a boss portion 24 having a through hole 24a penetrating in the thickness direction. Note that FIG. 2 shows a planar state when a retainer 50 described later is disposed with respect to the TCC 20, and the illustration of the cylinder block 2 existing behind (the back side of the drawing) is omitted.

  Further, as shown in FIG. 3, the TCC 20 has a groove 21a formed on the back side (seal surface side) of the end 23 attached to the cylinder head 1 and the cylinder block 2 (see FIG. 1). The groove portion 21a extends in the Z direction on the inner side of the through hole 22a, and is configured such that a later-described seal member 7 (see FIG. 5) is fitted into the groove portion 21a. Further, as shown in FIG. 1, the TCC 20 has a side portion of the engine body 10 (an edge portion 2b of the cylinder head 1 and the cylinder block 2) in a state where the front end portion 40a on the X2 side of the crankshaft 40 is inserted into the through hole 22a. ) Using bolts 90.

  Here, as shown in FIG. 5, the crankshaft 40 is provided with the oil seal 5 at a portion corresponding to the through hole 22 a of the TCC 20. Further, the oil seal 5 is not directly held in the inner peripheral surface of the through hole 22a of the TCC 20 and held by the TCC 20, but is held by a retainer 50 made of aluminum alloy. The retainer 50 has a predetermined mounting structure and is mounted on the engine body 10 side so that the oil seal 5 is mounted in the vicinity of the TCC 20 of the crankshaft 40. Further, the oil seal 5 prevents the oil in the crankcase 3 (see FIG. 1) from leaking around the crankshaft 40 to the outside of the engine body 10 (see FIG. 1). The retainer 50 is an example of the “oil seal fixing member” in the present invention.

  As shown in FIGS. 1 and 4, the retainer 50 is formed with a boss portion 52 having a through hole 52 a in the center portion along the X direction of the main body portion 51. The through hole 52a passes through the main body 51 in the thickness direction, and is configured such that the front end portion 40a (see FIG. 1) of the crankshaft 40 is inserted through the through hole 52a. As shown in FIG. 5, the retainer 50 has a cross-sectional structure, as shown in FIG. 5, on the inner peripheral surface of the through hole 52 a of the boss portion 52, there is an annular retaining portion 52 b protruding so as to reduce the inner diameter along the Y direction. Is formed. Further, the oil seal 5 is press-fitted and fixed in the through hole 52a from the outside (X2 side) to the inside (X1 side). The press-fitted oil seal 5 is prevented from excessively moving to the cylinder block 2 side (X1 side) by the retaining portion 52b.

  When the retainer 50 is viewed from the back side (the inner surface 50b side), the retainer 50 has a pair of end portions 53 as shown in FIG. The end 53 is formed at the tip of an arm 51a that extends in the longitudinal direction (Y1 direction and Y2 direction) around the through hole 52a. Further, each end portion 53 has a mounting hole 54a into which a later-described knock pin 11 is fitted and a boss portion 55 having a mounting hole 55a into which a later-described bolt 90 is inserted adjacent to each other in the Z direction. Is provided. In this case, the Y1 side end portion 53 is provided with one mounting hole 54a and one boss portion 55 (mounting hole 55a), and the Y2 side end portion 53 has one mounting hole 54a and one mounting hole. A pair of boss portions 55 (mounting holes 55a) are provided so as to sandwich 54a from above and below (Z direction). Further, the mounting hole 54a and the mounting hole 55a penetrate the end portion 53 in the thickness direction. The inner surface 50b is an example of the “facing surface” in the present invention.

  Further, as shown in FIG. 5, the knock pin 11 is fixed to the edge 2 b of the cylinder block 2 corresponding to the end 53 of the retainer 50 so that a part thereof protrudes in the direction of the arrow X <b> 2. The metal knock pin 11 is press-fitted into the fixing hole 2c provided in each of the Y1 side edge 2b and the Y2 side edge 2b of the cylinder block 2 by a predetermined depth. The outer diameter of the knock pin 11 is only slightly smaller than the inner diameter of the mounting hole 54a of the retainer 50. Thereby, in a state where the retainer 50 is put on the outer surface 20a from the outside of the TCC 20, the mounting hole 54a of the end portion 53 on the Y1 side is fitted to the knock pin 11 (see FIG. 1) corresponding to the Y1 side, And the attachment hole 54a of the edge part 53 by the side of Y2 is fitted by the knock pin 11 corresponding to the Y2 side. In this state, the bolts 90 are respectively inserted into the mounting holes 55a of the three boss portions 55, and the lower surface of the boss portion 55 is directly fixed to the fixing holes 2d of the edge portion 2b of the cylinder block 2. Yes.

  Thus, when the retainer 50 is assembled to the cylinder block 2 so as to straddle the TCC 20 in the Y direction, the retainer 50 is positioned in the mounting surface (YZ plane) with respect to the cylinder block 2. Yes. Further, the metal retainer 50 is accurately assembled to the metal cylinder block 2 by fitting the knock pin 11 and the mounting hole 54a, so that the center of the through hole 52a is aligned with the axis of the crankshaft 40. Accurately aligned. Thereby, the oil seal 5 is press-fitted into the crankshaft 40 with high accuracy.

  As shown in FIG. 3, the TCC 20 has an annular groove 21b around the boss 22 on the outer surface 20a on the X2 side. As shown in FIG. 5, an annular seal member 6 made of an elastic material is fitted in the groove 21b. The seal member 6 is in contact with a portion of the inner surface 50b around the boss portion 52 of the retainer 50 facing the TCC 20 through a portion exposed on the outer surface 20a from the groove portion 21b. That is, the seal member 6 is disposed between the retainer 50 (the boss portion 52) and the TCC 20 (the boss portion 22), and the seal member 6 is crushed in the direction of the arrow X1 and the TCC 20 (the boss portion 22). ) Of the outer surface 20a corresponding to the vicinity of the seal member 6 and the inner surface 50b of the retainer 50 (boss portion 52).

  Further, as shown in FIG. 5, a seal member 7 made of an elastic material is fitted in a groove portion 21 a formed on the back surface side (the inner surface 20 b side that is the X1 side) of the end portion 23 in the TCC 20. . The seal member 7 is in contact with the edge 2b facing the TCC 20 of the cylinder block 2 via a portion exposed on the inner surface 20b from the groove 21a. That is, the seal member 7 is disposed between the cylinder block 2 (the edge 2b) and the TCC 20 (the X1 side surface of the end 23), and the seal member 7 is crushed in the direction of the arrow X1. The cylinder block 2 is in close contact with the edge 2b and the X1-side surface of the end 23 of the TCC 20. As a result, the TCC 20 has a predetermined separation distance (about 0.5 mm or more from the cylinder block 2 in the direction of the arrow X2 by the seal member 7 being sandwiched between the end 23 formed in a flange shape and the edge 2b. 3mm or less) and is fixed in a floating state.

  Therefore, in the engine 100, as shown in FIG. 1, the TCC 20 interposes the seal member 7 along the edge 2b on the side (X2 side) of the engine body 10 (the cylinder head 1 and the cylinder block 2), and the bolt 90 Is attached in the direction of arrow X1. In this state, the retainer 50 is placed on the front side (X2 side) with the seal member 6 interposed so as to straddle the outer surface 20a of the portion of the TCC 20 corresponding to the crankshaft 40 protruding outward from the through hole 22a in the Y direction. ). Thereby, as shown in FIG. 2, the TCC 20 has a region S in which the retainer 50 is overlapped with the TCC 20. The region S is an example of the “region in which the oil seal fixing member and the cover member overlap each other” in the present invention.

  Here, in the first embodiment, as shown in FIG. 3, the resin-made TCC 20 is formed with a circumferential wall 26 extending in the direction of the arrow X <b> 2 (the front side in the drawing) away from the outer surface 20 a. The circumferential wall 26 is seamlessly formed in a predetermined region of the outer surface 20a, and a region 20c surrounded by the circumferential wall 26 is provided on the outer surface 20a. A boss portion 22 is disposed at the center of the region 20c. As shown in FIG. 5, when the TCC 20 and the retainer 50 are attached to the cylinder block 2 (engine body 10) in this order, the retainer 50 and the TCC 20 overlap each other by the circumferential wall 26 (see FIG. 2). Is configured to be surrounded. The arrow X2 direction is an example of the “first direction” in the present invention.

  That is, the engine 100 is configured such that a space 101 surrounded by the circumferential wall 26 is formed between the retainer 50 and the TCC 20 by the circumferential wall 26 provided circumferentially on the outer surface 20 a of the TCC 20. Yes. In other words, the space constituting the space 101 by the peripheral wall 26, the region 20c of the outer surface 20a of the TCC 20, and the flat inner surface 50b of the retainer 50 facing the region 20c in the direction of the arrow X2. A structure is configured. A space 101 between the retainer 50 and the TCC 20 constitutes a Helmholtz resonance section.

  Further, in the first embodiment, the circumferential wall 26 forming the space 101 serving as the Helmholtz resonance part in the region S (see FIG. 2) has a flat inner surface 50b of the retainer 50 whose tip 26a faces in the arrow X1 direction. The gap T is formed so as to have a gap T between them. That is, the tip 26a is not in contact with the inner surface 50b. Further, the entrance (opening) of the space 101 having the gap T is formed in a circumferential shape in plan view. And the clearance gap T connected cyclically | annularly in the circumferential direction is adjusted to the predetermined | prescribed magnitude | size so that the space 101 as a Helmholtz resonance part may have the resonance frequency which exhibits a silencing effect. Accordingly, the volume of the gap T connected in an annular shape is obtained by the product of the width of the tip 26a, the facing interval (size of the gap), and the peripheral length of the tip 26a. The gap T depends on the shape of the space 101, and noise generated due to vibration of the engine body 10, which is caused by the turning operation of the crankshaft 40, particularly inside the TCC 20 and in the vicinity of the crankshaft 40. Set to a magnitude that cancels out the frequency corresponding to the maximum value of the noise accompanying the vibration of the valve system timing member (such as the operation sound in the meshing operation of the timing chain 4 and the crankshaft timing sprocket 41) and the value in the vicinity thereof. Has been. The crankshaft timing sprocket 41 is an example of the “sprocket” in the present invention.

  As a result, in the engine 100, the circumferential wall 26 provided circumferentially on the outer surface 20 a of the TCC 20 causes the turning motion of the crankshaft 40 to be generated inside the TCC 20 due to the vibration of the engine main body 10 that is a source of generation. The generated noise (radiated sound) is configured to be difficult to diffuse outside the engine body 10. That is, the Helmholtz resonance is adjusted based on the ratio between the volume of the gap T and the volume of the space 101. Further, since the tip 26a of the circumferential wall 26 is not in contact with the inner surface 50b of the retainer 50 through the gap T, there is no friction between the retainer 50 and the circumferential wall 26 (TCC20), and the Helmholtz resonance portion is formed. The shape of the space 101 is maintained, and the peripheral wall 26 is not mechanically altered (deformed). Due to the space 101 in which the spatial shape as the Helmholtz resonance portion is maintained, a specific frequency band (frequency at which the radiated sound is at the maximum value and its vicinity) among the noise (radiated sound) caused by the vibration of the engine body 10. ) Is canceled regardless of the usage time of the engine 100.

  In the first embodiment, as shown in FIGS. 2 and 5, the space 101 between the retainer 50 and the TCC 20 surrounded by the circumferential wall 26 is an engagement portion between the timing chain 4 and the crankshaft timing sprocket 41. It arrange | positions so that it may overlap with 41a. Therefore, the meshing portion 41a where the timing chain 4 and the crankshaft timing sprocket 41 that are one of the noise sources of the engine body 10 mesh with each other is formed by the circumferential wall 26 that is circumferentially viewed from the direction in which the crankshaft 40 extends. Surrounded.

  Further, as shown in FIG. 4, the end portion 53 of the retainer 50 protrudes at a portion of the main body portion 51 closer to the inside than the boss portion 55 with a predetermined protrusion height in the arrow X1 direction (front side of the paper). A contact portion 56 is provided. Further, the contact portion 56 is formed continuously from the end portion on the Z1 side of the main body portion 51 to the end portion on the Z2 side. As a result, as shown in FIG. 5, the portion of the outer surface 20a corresponding to the vicinity of the seal member 6 of the TCC 20 is disposed with a gap with respect to the inner surface 50b of the retainer 50. The contact portion 56 is configured to contact the X2 side surface of the end portion 23 in the vicinity of the seal member 7 and from the side opposite to the side where the seal member 7 is provided.

  Further, the TCC 20 has a flange-shaped end portion 25a in which a cross section of the main body portion 21 is opened to the head cover 30 side (Z1 side), and a flange shape in which a cross section of the main body portion 21 is opened to the crankcase 3 side (Z2 side). End portion 25b. The TCC 20 and the head cover 30 are coupled using bolts (not shown) with the end 25a facing the mounting portion 30a of the head cover 30 from below, and the end 25b is connected to the mounting portion of the crankcase 3. The TCC 20 and the crankcase 3 are coupled using bolts (not shown) in a state of facing the 3c from above. A seal member (not shown) is sandwiched between the end portion 25a and the attachment portion 30a and between the end portion 25b and the attachment portion 3c.

  Further, as shown in FIG. 1, in the TCC 20, the crankshaft timing sprocket 41 and the camshaft timing sprocket 42 for driving the camshaft 45 incorporated in the cylinder head 1 are connected by the timing chain 4. It is. Further, outside the TCC 20, a crank pulley (not shown) is attached to the front end portion 40a of the crankshaft 40. Auxiliaries such as a cooling water circulation water pump and a vehicle air conditioning compressor attached to the engine 100 are driven by a belt hung on a crank pulley. Further, the rear end portion 40b of the crankshaft 40 is connected to a power transmission unit (not shown) including a transmission or the like. The engine 100 in the first embodiment is configured as described above.

  In the first embodiment, the following effects can be obtained.

  That is, in the first embodiment, as described above, the retainer 50 and the TCC (timein chain cover) 20 are provided in a circumferential shape so as to surround the overlapping region S when viewed from the direction in which the crankshaft 40 extends (X direction). In addition, the peripheral wall 26 protruding in the direction of the arrow X2 facing each other of the retainer 50 and the TCC 20 is provided on the outer surface 20a of the TCC 20, whereby the peripheral wall 26 provided circumferentially on the outer surface 20a of the TCC 20 The noise generated due to the vibration of the engine body 10 that is the source of the turning operation of the motor 40, and particularly the noise accompanying the vibration of the valve timing system inside the TCC 20 and in the vicinity of the crankshaft 40 (timing chain 4 And the crankshaft timing sprocket 41 You can enclose a kick like operation sound) to the inside (area 20c) of the circumferential wall 26. That is, it is possible to make it difficult for the noise (radiated sound) of the engine body 10 to leak to the outside by the circumferential wall 26 provided in a circumferential shape. In this case, for example, unlike the case where the vibration energy of the TCC 20 that vibrates together with the engine body 10 is converted into friction energy (thermal energy) to reduce the vibration of the TCC 20 and the noise reduction associated therewith, the engine 100 passes over time. In addition, since the configuration in which the noise of the engine body 10 is enclosed inside the peripheral wall 26 (region 20c) using the peripheral wall 26 that does not cause mechanical deterioration, the noise reduction effect is deteriorated with time. There will be no (decrease). As a result, the effect of suppressing noise (radiated sound) resulting from the vibration of the engine body 10 can be maintained over a long period of time.

  Moreover, in 1st Embodiment, since the rigidity of resin-made TCC20 can be improved by providing the surrounding circumferential wall 26 in the outer surface 20a of TCC20, the vibration of the engine main body 10 is made from resin-made TCC20. Can be suppressed from being noticed. This also reduces the noise (radiated sound) level itself diffused from the engine body 10 due to the vibration of the TCC 20 accompanying the vibration of the engine body 10 without being affected by the long-term use of the engine 100. be able to.

  In the first embodiment, the space 101 between the retainer 50 and the TCC 20 surrounded by the circumferential wall 26 constitutes a Helmholtz resonance part, and the distal end 26 a of the circumferential wall 26 and the distal end of the circumferential wall 26. By adjusting the size of the gap T between the inner surface 50b of the retainer 50 opposed to 26a, the resonance frequency is set so that the radiated sound has a maximum value and a frequency in the vicinity thereof. Thereby, the space 101 which becomes a Helmholtz resonance part can be easily formed between the retainer 50 and the TCC 20 by surrounding the circumferential wall 26. And the gap T of the entrance part (opening part) of the space 101 as the Helmholtz resonance part is set so that the Helmholtz resonance part has a resonance frequency (for example, a frequency at which the radiated sound has a maximum value and its vicinity) that exhibits a silencing effect. Since the size (the size of the gap T between the tip 26a of the circumferential wall 26 and the inner surface 50b of the retainer 50) is adjusted, the space 101 between the retainer 50 and the TCC 20 surrounded by the circumferential wall 26 is adjusted. A specific frequency band of noise (radiated sound) caused by vibration of the engine body 10 can be effectively canceled by the (Helmholtz resonance unit). At this time, the distal end 26a of the circumferential wall 26 is not in contact with the inner surface 50b of the retainer 50 through the gap T, so that friction between the retainer 50 and the circumferential wall 26 (TCC20) does not occur, and the Helmholtz resonance. The shape of the space 101 as a part is maintained. As a result, unlike the case where noise is reduced by converting vibration energy of the engine body 10 into friction energy, etc., in addition to the effect of suppressing the continuous diffusion of noise due to the circumferential wall 26 that does not cause mechanical deterioration over time. Thus, even with the space 101 that continues to function as the Helmholtz resonance part, the noise (radiated sound) level itself caused by the vibration of the engine body 10 can be effectively reduced.

  Further, in the first embodiment, the engine body 10 includes the timing chain 4 and the crankshaft timing sprocket 41, and between the retainer 50 and the TCC 20 surrounded by the circumferential wall 26 when viewed from the direction in which the crankshaft 40 extends. The space 101 is arranged so as to overlap the meshing portion 41 a between the timing chain 4 and the crankshaft timing sprocket 41. As a result, the circumferential wall 26 provided circumferentially as seen from the extending direction of the crankshaft 40 has a meshing portion 41a in which the timing chain 4 and the crankshaft timing sprocket 41 that are one of the noise sources of the engine body 10 mesh. Can be easily surrounded by. Therefore, it is possible to effectively suppress the noise radiated (diffused) from the meshing portion 41a from penetrating to the outside through the portion (region 20c) corresponding to the space 101 where the TCC 20 and the retainer 50 overlap in the direction of the arrow X2. can do.

  In the first embodiment, the TCC 20 is made of resin, and the retainer 50 is made of an aluminum alloy. Accordingly, even when the TCC 20 is made of resin for the purpose of reducing the weight of the engine 100 and the retainer 50 is made of aluminum alloy for the purpose of attaching the oil seal 5 to the crankshaft 40 with high accuracy, The circumferential wall 26 provided in the circumferential shape can effectively and easily obtain the noise reduction effect in the engine body 10 (continuous reduction effect of radiated sound caused by the vibration of the engine body 10). Further, by making the TCC 20 assembled to the side end portion of the engine body 10 made of resin, it is possible to make it easier to improve the sound absorption of noise diffusing from the engine body 10 than when the TCC 20 is made of a metal member. it can.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS. In the second embodiment, an example in which the peripheral wall 257 is formed on the retainer 250 in addition to the peripheral wall 26 on the TCC 20 side will be described. The circumferential wall 257 is an example of the “first circumferential wall” in the present invention, and the circumferential wall 26 is an example of the “second circumferential wall” in the present invention. The retainer 250 is an example of the “oil seal fixing member” in the present invention. In the drawing, the same reference numerals as those in the first embodiment are attached to the same components as those in the first embodiment.

  The engine 200 according to the second embodiment of the present invention is configured to hold the oil seal 5 using an aluminum alloy retainer 250 as shown in FIG. Here, when the retainer 250 is viewed from the back side, as shown in FIG. 6, a circumferential wall 257 is formed that extends in the direction of arrow X <b> 1 (the front side in the drawing) away from the inner surface 250 b of the main body 51. The circumferential wall 257 is circumferentially seamlessly formed on the inner surface 250b in the circumferential direction, and a region 250c surrounded by the circumferential wall 257 is provided on the inner surface 250b. The engine 200 is an example of the “internal combustion engine” in the present invention. The inner surface 250b is an example of the “opposing surface” in the present invention.

  As shown in FIG. 7, in a state where the TCC 20 and the retainer 250 are attached in this order to the cylinder block 2 (engine body 10), the region S where the retainer 250 and the TCC 20 overlap each other by the circumferential wall 26 and the circumferential wall 257. (See FIG. 6) is surrounded. In this case, a space 201 (region 250 c) surrounded by the circumferential wall 257 is formed between the retainer 250 and the TCC 20 by the circumferential wall 257 provided circumferentially on the inner surface 250 b of the inner retainer 250. .

  Moreover, in 2nd Embodiment, as shown in FIG. 7, the surrounding wall 257 is formed so that the front-end | tip 257a may have the clearance gap T between the outer surface 20a of TCC20 which opposes arrow X1 direction. That is, in addition to the tip 26 a, the tip 257 a is not in contact with the outer surface 20 a of the TCC 20. The gap T is formed in a circumferential shape in plan view. Also in the second embodiment, the gap T is adjusted to a predetermined size so that the space 201 as the Helmholtz resonance part has a resonance frequency that exhibits a silencing effect. Thereby, in the engine 200, the Helmholtz resonance part is comprised by the space 201 between the retainer 250 and TCC20. The outer surface 20a is an example of the “opposing surface” in the present invention.

  Therefore, in the engine 200, the turning operation of the crankshaft 40 is performed by the circumferential wall 26 circumferentially provided on the outer surface 20a of the TCC 20 and the circumferential wall 257 circumferentially provided on the inner surface 250b of the retainer 250. The noise generated inside the TCC 20 due to the vibration of the engine body 10 as a generation source is difficult to diffuse outside the engine body 10. In addition, a specific frequency of noise (radiated sound) caused by vibration of the engine body 10 due to the space 201 (Helmholtz resonance part) between the retainer 250 and the TCC 20 surrounded by the circumferential wall 26 and the circumferential wall 257. The band (frequency at which the radiated sound is the maximum value and its vicinity) is canceled out. The outer surface 20a is an example of the “opposing surface” in the present invention. The direction of arrow X1 is an example of the “first direction” in the present invention.

  In the second embodiment, the inner circumferential wall 257 and the outer circumferential wall 26 have a predetermined interval in a direction (Y direction and Z direction) perpendicular to the arrow X2 direction in which the crankshaft 40 extends. It is facing away. That is, as shown in FIG. 7, a sound path 202 is formed between the circumferential wall 257 and the circumferential wall 26 so as to be intertwined like a maze with a predetermined interval. The sound path 202 is formed in a circumferential shape along the circumferential wall 257 (circumferential wall 26) as viewed in a plan view.

  Thereby, in the region S where the TCC 20 and the retainer 250 overlap (see FIG. 6), the region 250c that is inside the circumferential wall 257 and the region S that is outside the region 250c (outside the circumferential wall 26). The area) is connected only by the sound path 202 where the TCC 20 and the retainer 250 do not contact each other (do not rub against each other). Further, the resonance frequency of the space 201 in which the space shape as the Helmholtz resonance portion is maintained by the sound path 202 is set to a predetermined value. At the same time, a structure in which the sound insulation effect is further enhanced is formed in the region S by the circumferential wall (the circumferential wall 257 and the circumferential wall 26) having the sound path 202 and having a double structure. ing. In addition, the other structure of the engine 200 by 2nd Embodiment is the same as that of the said 1st Embodiment.

  In the second embodiment, the following effects can be obtained.

  In the second embodiment, the circumferential wall 26 extending in the direction of the arrow X2 toward the retainer 250 is provided in the TCC 20, and the direction orthogonal to the direction of the arrow X2 in which the crankshaft 40 extends with respect to the circumferential wall 26 (Y direction). And the Z-direction) are arranged so as to face each other with a gap T therebetween, and a circumferential wall 257 extending in the direction of the arrow X1 toward the TCC 20 is provided in the retainer 250. Accordingly, it is possible to form a circumferential wall in which the circumferential wall 26 surrounds the circumferential wall 257 from the outside in a plan view. In other words, a circumferential wall (a circumferential wall 26 and a circumferential wall 257) having a double structure of a circumferential wall 26 extending from the TCC 20 toward the retainer 250 and a circumferential wall 257 extending from the retainer 250 toward the TCC 20. Thus, a maze structure (sound insulation structure) composed of the sound path 202 can be formed in a circumferential shape in a region near the outer edge portion of the space 201 between the retainer 250 and the TCC 20. Thereby, it is possible to further suppress leakage of noise generated inside the TCC 20 due to vibration of the engine body 10 to the outside of the engine body 10.

  In the second embodiment, the space 201 between the retainer 250 and the TCC 20 surrounded by the circumferential wall 257 constitutes a Helmholtz resonance part, and the distal end 26 a of the circumferential wall 26 and the distal end 26 a of the circumferential wall 26. The size of the gap T between the inner surface 250b of the retainer 250 opposite to each other and the size of the gap T between the tip 257a of the circumferential wall 257 and the outer surface 20a of the TCC 20 opposite to the tip 257a of the circumferential wall 257 Then, by adjusting the size of the gap T between the circumferential wall 257 and the circumferential wall 26, respectively, a predetermined resonance frequency is set. Thereby, the space 201 used as the Helmholtz resonance part can be easily formed between the retainer 250 and the TCC 20 by surrounding the circumferential wall (the circumferential wall 257 and the circumferential wall 26) having a double structure. . Then, the size of the gap T of the sound path 202 serving as the entrance portion of the space 201 as the Helmholtz resonance portion (the distal end 26a of the circumferential wall 26 and the retainer 250 so that the Helmholtz resonance portion has a resonance frequency exhibiting a silencing effect). The size of the gap T between the inner surface 250b of the TCC 20 and the size of the gap T between the tip 257a of the circumferential wall 257 and the outer surface 20a of the TCC 20 facing the tip 257a of the circumferential wall 257, The size of the gap T between the wall 257 and the circumferential wall 26 is adjusted together, and the space 201 (Helmholtz resonance portion) surrounded by the inner circumferential wall 257 is caused by the vibration of the engine body 10. It is possible to effectively cancel a specific frequency band of noise (radiated sound).

  At this time, the tip 26a of the circumferential wall 26 is not in contact with the inner surface 250b of the retainer 250 via the gap T, and the tip 257a of the circumferential wall 257 is outside the TCC 20 via the gap T. Since the surface 20a is not in contact with each other, the retainer 250 (circumferential wall 257) and the TCC 20 (circumferential wall 26) do not rub against each other, and the shape of the space 201 as the Helmholtz resonance portion is maintained. As a result, in addition to the continuous noise suppression effect by the circumferential wall (circumferential wall 257 and circumferential wall 26) having a double structure, the space 201 that continues to function as the Helmholtz resonance part also provides the engine body. The noise (radiated sound) level itself due to the vibration of 10 can be further and continuously reduced.

  Further, in the second embodiment, in addition to providing the circumferential circumferential wall 26 in the resin-made TCC 20, the TCC 20 and the retainer 250 are also provided in the metallic retainer 250 by providing the circumferential circumferential wall 257. Therefore, it is possible to suppress the vibration of the engine body 10 from being noticeably transmitted to the TCC 20 and the retainer 250. Also by this, the noise (radiated sound) level itself diffused from the engine body 10 due to the vibration of the TCC 20 and the retainer 250 due to the vibration of the engine body 10 without being affected by the long-term use of the engine 200 itself. Can be reduced. The remaining effects of the second embodiment are similar to those of the aforementioned first embodiment.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG. 5, FIG. 8, and FIG. In the third embodiment, an example in which a sound absorbing material 301 is provided in a space 101 (see FIG. 5) between the retainer 50 and the TCC 20 formed by the circumferential wall 26 on the TCC 20 side will be described. In the figure, components similar to those in the first embodiment are denoted by the same reference numerals as those in the first embodiment.

  In the engine 300 according to the third embodiment of the present invention, as shown in FIG. 8, the oil seal 5 is installed using the retainer 50 in a state where the TCC 20 is attached to the engine body 10 (the cylinder head 1 and the cylinder block 2). Configured to hold. In the third embodiment, a sound absorbing material 301 made of a material having a sound absorbing effect is further arranged in a space 101 (see FIG. 5) between the retainer 50 and the TCC 20 formed by the circumferential wall 26 on the TCC 20 side. ing. 8 is a cross-sectional view taken along the line 350-350 (dashed line) in FIG. The engine 300 is an example of the “internal combustion engine” in the present invention.

  Here, the sound absorbing material 301 may be configured using a foamed material (foamed rubber material) such as a urethane material, or the sound absorbing material 301 may be configured using a fiber material such as glass wool. Also, a vinyl sound-absorbing material containing bubbles can be applied. That is, the sound absorbing material 301 is preferably configured using a porous material including an air layer.

  Further, as shown in FIG. 9, the sound absorbing material 301 is spread in the space 101 so as to surround the crankshaft 40 and the oil seal 5 when viewed from the direction in which the crankshaft 40 extends. Therefore, the sound absorbing material 301 is disposed so as to overlap the meshing portion 41a (see FIG. 8) between the timing chain 4 and the crankshaft timing sprocket 41. As a result, in the third embodiment, the noise of the engine body 10 passes through the portion (region 20c) corresponding to the space 101 (see FIG. 5) where the TCC 20 and the retainer 50 overlap with each other in the direction of the arrow X2. This effectively suppresses diffusion outside.

  As shown in FIG. 8, even when the sound absorbing material 301 is spread, a slight gap remains in the space 101 (see FIG. 5) where the TCC 20 and the retainer 50 overlap. For example, a gap T is left between the tip 26 a of the circumferential wall 26 and the portion of the inner surface 50 b of the retainer 50. Thereby, even if the sound absorbing material 301 is provided, the tip 26a does not contact the inner surface 50b circumferentially, and the retainer 50 and the circumferential wall 26 (TCC20) are not rubbed. In addition, the other structure of the engine 300 by 3rd Embodiment is the same as that of the said 1st Embodiment.

  In the third embodiment, the following effects can be obtained.

  In the third embodiment, as described above, the sound absorbing material 301 is provided in the space 101 between the retainer 50 and the TCC 20 surrounded by the circumferential wall 26. Thereby, the noise (radiated sound) accompanying the vibration of the engine body 10 can be absorbed by the sound absorbing material 301 in the space 101 between the retainer 50 and the TCC 20 surrounded by the circumferential wall 26. Therefore, in this case as well, the engine 300 is different from the configuration in which the vibration energy of the engine body 10 is converted into friction energy to reduce noise, so that the noise generated by the circumferential wall 26 that does not cause mechanical deterioration over time is not obtained. In addition to the continuous diffusion suppression effect, the noise reduction effect can be continuously obtained by the sound absorbing material 301 that absorbs noise. As a result, noise (radiated sound) resulting from the vibration of the engine body 10 can be more effectively suppressed. The remaining effects of the third embodiment are similar to those of the aforementioned first embodiment.

(Fourth embodiment)
Next, a fourth embodiment will be described with reference to FIGS. 5, 8, 10, and 11. In the fourth embodiment, unlike the third embodiment in which the sound absorbing material 301 (see FIG. 8) is arranged almost in the space 101 (see FIG. 5), the sound absorbing material 401 is partially provided in the space 101. An example will be described. In the figure, components similar to those in the third embodiment are denoted by the same reference numerals as those in the third embodiment.

  In the engine 400 according to the fourth embodiment of the present invention, as shown in FIG. 11, the space 101 between the retainer 50 and the TCC 20 formed by the circumferential wall 26 on the TCC 20 side is made of a material having a sound absorbing effect. A sound absorbing material 401 is arranged. The engine 400 is an example of the “internal combustion engine” in the present invention.

  Here, in the fourth embodiment, as shown in FIGS. 10 and 11, the sound absorbing material 401 is partially filled in the space 101. That is, the space 101 includes a region filled (arranged) with the sound absorbing material 401 and a region composed of an air layer not filled (arranged) with the sound absorbing material 401. Therefore, in a state where the sound absorbing material 401 is partially disposed in the space 101, the space structure (the peripheral wall 26, the region 20c (outer surface 20a) of the TCC 20), and the region 20c that constitute the space 101 are opposed to each other. A space structure formed by the inner surface 50b of the retainer 50) has a resonance frequency that exhibits a silencing effect, and between the tip 26a of the circumferential wall 26 and the inner surface 50b of the retainer 50 that the tip 26a faces. The size of the gap T is adjusted. 10 is a cross-sectional view taken along the line 450-450 (dashed line) in FIG.

  Further, as shown in FIG. 11, the sound absorbing material 401 is disposed in the space 101 so as to surround the crankshaft 40 and the oil seal 5. Further, the sound absorbing material 401 is disposed so as to overlap the meshing portion 41 a between the timing chain 4 and the crankshaft timing sprocket 41. In addition, the other structure of the engine 400 by 4th Embodiment is the same as that of the said 1st Embodiment.

  In the fourth embodiment, the following effects can be obtained.

  In the fourth embodiment, as described above, by partially filling the space 101 with the sound absorbing material 401, the space 101 is filled (arranged) with the sound absorbing material 401, and the sound absorbing material 401 is filled (arranged). And a region composed of a non-air layer. Thereby, even in a state where the sound absorbing material 401 is arranged in the space 101, the spatial structure constituting the space 101 can function as a Helmholtz resonance unit that exhibits a silencing effect in a specific frequency band. Therefore, in the engine 400, in addition to the sound absorbing effect by the sound absorbing material 401, the noise (radiated sound) level itself due to the vibration of the engine body 10 is also reduced by the spatial structure constituting the space 101 that continues to function as the Helmholtz resonance unit. Can continue to reduce.

  In the fourth embodiment, the sound absorbing material 401 is disposed in the space 101 so as to surround the crankshaft 40 and the oil seal 5 and to overlap with the meshing portion 41 a between the timing chain 4 and the crankshaft timing sprocket 41. Thereby, in the engine 400, even when the sound absorbing material 401 is partially arranged in the space 101, the noise of the engine body 10 including the noise radiated from the meshing portion 41a overlaps the TCC 20 and the retainer 50. It is possible to effectively suppress the portion (region 20c) corresponding to the space 101 from penetrating in the direction of the arrow X2 and diffusing outside. The remaining effects of the fourth embodiment are similar to those of the aforementioned third embodiment.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the first embodiment, the example in which the space 101 is formed by forming the circumferential wall 26 extending toward the inner surface 50b of the retainer 50 on the outer surface 20a of the TCC 20 has been described. Not limited. That is, as shown in the second embodiment, only the peripheral wall 257 extending toward the outer surface 20a of the TCC 20 is formed on the inner surface 250b of the retainer 250, and the peripheral wall 26 is not formed. The “space” may be configured.

  In the first embodiment, the example is shown in which the space 101 is formed by forming the circumferential wall 26 extending toward the flat inner surface 50b of the retainer 50 on the outer surface 20a of the TCC 20. Is not limited to this. That is, a circumferential wall that protrudes from each of the outer surface 20a of the TCC 20 and the inner surface 50b of the retainer 50 so as to be opposed to each other in the X direction (first direction) at a predetermined interval is provided. You may comprise the "space" of this invention. Even when configured as in this modification, the “space” of the present invention can be provided between the TCC 20 and the retainer 50, and this space can function as a Helmholtz resonance section.

  In the second embodiment, the example in which the circumferential wall 26 is formed in the TCC 20 and the circumferential wall 257 is formed in the retainer 250 to configure the “circumferential wall” of the present invention in a double structure is shown. The present invention is not limited to this. For example, the “circumferential wall” of the present invention may be further formed in a single or double manner inside the peripheral wall 257. In this way, by continuously forming the “circumferential wall” of the present invention, the continuous sound insulation effect against the noise of the engine body 10 is further enhanced by using the region S where the TCC 20 and the retainer 250 overlap. Can do.

  In the above first to fourth embodiments, the “circumferential wall” of the present invention is shown as an example of being circumferentially formed along the outer shape of the main body 51 in the retainer 50 (250). Is not limited to this. The planar shape of the “circumferential wall” of the present invention may be other than the above. For example, the “circumferential wall” of the present invention may be formed to have a circular shape or an elliptical shape (long hole shape) so as to surround the crankshaft 40 and the oil seal 5. However, it is preferable that the space between the retainer 50 constituted by the circumferential wall and the TCC 20 overlaps the meshing portion 41a between the timing chain 4 and the crankshaft timing sprocket 41 or is located on the outer side.

  Moreover, in the said 1st-4th embodiment, although the example which formed the circumferential wall 26 (257) in the circumferential shape seamlessly was shown, this invention is not limited to this. That is, as long as the retainer 50 (250) and the TCC 20 are provided in a circumferential shape so as to surround the overlapping region S, a circumferential wall in which a part of the wall is notched may be provided. Further, in this case, the end portion of the peripheral wall of the notched portion and the vicinity thereof are configured to face (overlap) each other with a predetermined interval in the second direction (Y direction or Z direction). May be.

  Moreover, although the said 3rd Embodiment showed the example which has arrange | positioned the sound-absorbing material 301 substantially in the space 101, this invention is not limited to this. For example, “sound absorbing material” that is divided into a plurality of pieces may be arranged in an island shape in the space 101.

  In the second embodiment, only the example in which the circumferential wall 26 is formed in the TCC 20 and the circumferential wall 257 is formed in the retainer 250 to configure the “circumferential wall” of the present invention in a double structure is shown. However, the present invention is not limited to this. That is, the sound absorbing material 301 shown in the third embodiment may be spread in the space 201 inside the circumferential wall having a double structure, or the sound absorbing material formed in the shape shown in the fourth embodiment. 401 may be arranged in a space 201 inside the circumferential wall having a double structure while leaving a part of the space 201 (existing).

  Moreover, in the said 1st-4th embodiment, the contact part which protrudes to the main-body part 51 of the retainer 50 (250) to X1 direction, and contact | abuts to the X2 side surface of the edge part 23 corresponding to the vicinity of the seal member 7 of TCC20. Although an example in which 56 is provided is shown, the present invention is not limited to this. For example, a contact portion that does not protrude from the retainer 50 may be provided. In this case, in the vicinity of the seal member 7, the flat back side (inner surface 50 b) of the retainer 50 may be brought into contact with the X2 side surface of the flat end portion 23 of the TCC 20, or A convex portion protruding in the X2 direction (retainer 50 side) may be provided, and the flat back side (inner surface 50b) portion of the retainer 50 may be brought into contact with the convex portion.

  Moreover, although the said 1st-4th embodiment showed about the example which comprised the retainer 50 (250) using the aluminum alloy, this invention is not limited to this. That is, you may comprise the "oil seal fixing member" of this invention using metal materials other than an aluminum alloy. Alternatively, the “oil seal fixing member” of the present invention may be configured using a resin material that ensures a predetermined rigidity. In this case, both the “cover member” and the “oil seal fixing member” of the present invention may be made of resin.

  Moreover, although the said 1st-4th embodiment showed about the example comprised so that TCC20 might consist of resin, this invention is not limited to this. That is, you may comprise the "cover member" of this invention using metal materials, such as aluminum alloy other than resin material, for example. Further, in this case, an internal combustion engine may be configured by attaching a resin “oil seal fixing member” ensuring a predetermined rigidity to a metal “cover member”.

  Moreover, although the said 1st-4th embodiment showed about the example which applied this invention to the engine 100 (200, 300, 400) for motor vehicles consisting of a gasoline engine, this invention is not limited to this. That is, in the case of an internal combustion engine having a crankshaft, the present invention relates to an assembly structure of a cover member and an oil seal fixing member relating to noise countermeasures in a gas engine other than a gasoline engine (internal combustion engines such as a diesel engine and a gas engine). May be applied. Further, the present invention may be applied to an assembly structure of a cover member and an oil seal fixing member relating to noise countermeasures of an internal combustion engine that is mounted as a drive source (power source) of equipment other than for automobiles, for example. .

DESCRIPTION OF SYMBOLS 1 Cylinder head 2 Cylinder block 3 Crankcase 4 Timing chain 5 Oil seal 10 Engine body (internal combustion engine body)
20 Timing chain cover (TCC) (Cover member)
20a Outer surface (opposite surface)
20c, 250c region 26 circumferential wall (second circumferential wall)
26a, 257a Tip 40 Crankshaft 41 Crankshaft timing sprocket (sprocket)
41a Mating portion 50, 250 Retainer (oil seal fixing member)
50b, 250b Inner surface (opposite surface)
100, 200, 300, 400 engine (internal combustion engine)
101, 201 space 257 circumferential wall (first circumferential wall)
301, 401 Sound absorbing material S region (region where oil seal fixing member and cover member overlap each other)
T clearance

Claims (6)

A cover member attached to a side of an internal combustion engine body having a crankshaft;
An oil seal fixing member that is disposed on the opposite side of the cover member from the internal combustion engine body and that fixes an oil seal attached to the crankshaft;
At least one of the oil seal fixing member and the cover member is provided in a circumferential shape so as to surround a region where the oil seal fixing member and the cover member overlap each other when viewed from the direction in which the crankshaft extends. An internal combustion engine comprising a fixed member and a circumferential wall projecting in a first direction facing each other of the cover member.   A space between the oil seal fixing member and the cover member surrounded by the circumferential wall constitutes a Helmholtz resonance part, and the tip of the circumferential wall and the tip of the circumferential wall face each other. 2. The internal combustion engine according to claim 1, wherein the internal combustion engine is set to have a predetermined resonance frequency by adjusting a size of a gap between at least one opposing surface of the seal fixing member and the cover member.   The circumferential wall includes a first circumferential wall extending from the oil seal fixing member toward the cover member, and a first direction perpendicular to the first direction in which the crankshaft extends with respect to the first circumferential wall. 3. The internal combustion engine according to claim 1, further comprising a second circumferential wall that is disposed to face each other at a predetermined interval in two directions and extends from the cover member toward the oil seal fixing member.   The internal combustion engine according to claim 1, further comprising a sound absorbing material provided in a space between the oil seal fixing member and the cover member surrounded by the peripheral wall. The internal combustion engine body includes a timing chain and a sprocket,
A space between the oil seal fixing member and the cover member surrounded by the peripheral wall as viewed from the extending direction of the crankshaft is disposed so as to overlap the meshing portion of the timing chain and the sprocket. The internal combustion engine according to any one of claims 1 to 4.   The internal combustion engine according to any one of claims 1 to 5, wherein at least one of the cover member and the oil seal fixing member is made of a resin.

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