Belt cover structure for internal combustion engine

Abstract

Provided is a belt cover which is for an internal combustion engine and has easy attachability and sealability.　This belt cover structure for an internal combustion engine has: an oil pump case OP and a lower cover 9 which cover a timing belt TB; and a side mount bracket 8 which is adjacent to an upper side of the lower cover 9 and is held by a cylinder block CB. The lower cover 9 and the side mount bracket 8 respectively have therein mating surfaces 96c, 86c which mate each other. A lower seal member 41 is disposed on the mating surface 96c, and the mating surface 86c is configured to cover the mating surface 96c from outside. The lower cover 9 and the side mount bracket 8 are fixed in a state in which the mating surface 86c of the side mount bracket 8 is pressed against the mating surface 96c of the lower cover 9, with the seal member 41 therebetween.

Description

[Technical field]

[0001] The present invention relates to a belt cover structure for an internal combustion engine, for protecting a timing belt attached to the internal combustion engine. [Background technology]

[0002] Some internal combustion engines mounted on vehicles use a timing belt (or a transmission belt such as a timing chain) to transmit the rotational power of the crankshaft to the camshaft in conjunction with the engine. In order to protect the timing belt from water and dust, a belt cover that covers the timing belt is placed on the cylinder block of the internal combustion engine. The belt cover needs to be detached from the cylinder block as necessary to inspect and replace the timing belt, etc.

[0003] In Patent Document 1, the timing belt cover is composed of three members, an upper cover and two lower covers, which are attached to the internal combustion engine body. The two lower covers engage with each other through a labyrinth structure formed on their mating surfaces. This structure allows one of the lower covers to be removed after removing the upper cover, and allows maintenance of the accessories attached to the cylinder block with the other lower cover still attached. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 61-179351 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the two lower covers are assembled in a labyrinth structure. When assembling in a labyrinth structure, there is little problem with ease of attachment and detachment when assembling in one direction, but when there are a large number of parts or the belt cover is configured three-dimensionally, it may be necessary to move the parts in multiple directions when attaching or detaching the parts. In this case, ease of attachment and detachment may become an issue. In addition to ease of attachment and detachment, the belt cover is required to have a sealing property for waterproofing and dustproofing.

[0006] The present invention has been made to solve the above problems, and has an object to provide a belt cover for an internal combustion engine that is easy to attach and detach and has sealing properties. [Means for solving the problem]

[0007] In order to achieve this object, the invention according to claim 1 provides a belt cover structure for an internal combustion engine (1), which is disposed on one side of an internal combustion engine body (a cylinder block CB in an embodiment (hereinafter the same in this section)) and accommodates at least a part of a timing belt (TB) that transmits power between a crankshaft (10) and a camshaft (11, 12, 13, 14), and which has an inner cover member (oil pump case OP) that covers the timing belt on a side closer to the internal combustion engine than the timing belt, and an outer cover member (lower cover 9) that covers the timing belt on a side farther from the internal combustion engine than the timing belt, and the outer cover member is a lower outer cover member (lower cover 9) that covers at least a periphery of the crankshaft. The lower outer cover member has a cover 9, and a side mount bracket (8) held by the internal combustion engine body is disposed adjacent to the upper part of the lower outer cover member, and the lower outer cover member and the side mount bracket each have a mating surface (96c, 86c) that mates with each other. A lower seal member (41) that seals the lower outer cover member and the side mount bracket is disposed on the mating surface (96c) of the lower outer cover member, and the mating surface (86c) of the side mount bracket is configured to cover the mating surface of the lower outer cover member from the outside, and the lower outer cover member and the side mount bracket are fixed in a state in which the mating surface of the side mount bracket is pressed against the mating surface of the lower outer cover member via the lower seal member. a water pump case (WP) is disposed on the one side surface of the internal combustion engine body, and the side mount bracket is configured such that an end (8a) on one side in a width direction, which is a direction perpendicular to the axial direction of the crankshaft, covers the water pump case and an end (8b) on the other side in the width direction is fixed to an outer surface (37) of the water pump case, and when the side mount bracket is attached, the side mount bracket is moved to the other side, and when the side mount bracket is removed, the side mount bracket is moved to the one side. It is characterized by the above.

[0008] In this way, the mating surface of the side mount bracket is configured to cover the mating surface of the lower outer cover member from the outside, so that the side mount bracket and the lower outer cover member, which are adjacent in the vertical direction, are fixed in a direction intersecting the vertical direction. As a result, when the side mount bracket is removed from the lower outer cover member, it can be removed in a direction intersecting the vertical direction. In this case, for example, even if it is difficult to remove the side mount bracket in the upward direction because another cover is arranged above the side mount bracket, the side mount bracket can be easily removed. In addition, the lower outer cover member and the side mount bracket are fixed in a state of being pressed against each other via the lower seal member. Thus, it is possible to provide a belt cover for an internal combustion engine that is easy to attach and detach and has a sealability.

[0010] Also In a configuration in which the side mount bracket is moved to one side when removed and to the other side when installed, the other end of the side mount bracket is fixed to the outer surface of the water pump case. This reduces the amount of axial movement of the other end of the side mount bracket when attaching or detaching the side mount bracket compared to when the other end covers the water pump case like the one end. This makes it possible to easily attach and detach the side mount bracket.

[0011] The invention according to claim 3 is a belt cover structure for an internal combustion engine (1) that is arranged on one side of an internal combustion engine body (cylinder block CB) and that houses at least a part of a timing belt (TB) that transmits power between a crankshaft and a camshaft, the belt cover structure having an inner cover member (front inner cover 2) that covers the timing belt on a side closer to the internal combustion engine than the timing belt, and an outer cover member (front outer cover 6) that covers the timing belt on a side farther from the internal combustion engine than the timing belt, the inner cover member having at least an upper inner cover member (front inner cover 2) that covers the periphery of the camshaft, the outer cover member having at least an upper outer cover member (front outer cover 6) that covers the periphery of the camshaft, a water pump case (WP) is arranged adjacent to and below the upper inner cover member, a side mount bracket (8) is arranged to cover the water pump case on a side farther from the internal combustion engine than the water pump case, the upper outer cover member is fixed above the side mount bracket via a first seal member (first upper seal member 51) provided on the side mount bracket, the upper inner cover member is fixed above the side mount bracket and above the water pump case via a second seal member (second upper seal member 52) provided on the side mount bracket, and an end (51a) of the first seal member and an end (52a) of the second seal member are arranged so as to be pressed against each other.

[0012] In this way, the first seal member that seals between the upper outer cover member and the side mount bracket, and the second seal member that seals between the upper inner cover member and the side mount bracket are arranged so that their ends are pressed against each other. This ensures sealing between the first seal member and the second seal member. In addition, since the water pump case is covered by the side mount bracket, maintenance of the water pump can be performed by removing the side mount bracket, making it easy to attach and detach. Thus, it is possible to provide a belt cover for an internal combustion engine that is easy to attach and detach and has sealing properties.

[0013] The invention of claim 4 is a belt cover structure for an internal combustion engine as described in claim 3, wherein the side mount bracket and the water pump case are formed to communicate with each other with a bolt boss portion (62) for inserting a fastening bolt (61), the side mount bracket has a mating surface (81) near the bolt boss portion that is mated across the upper inner cover member and the upper outer cover member, and a step shape (81a) is formed on the mating surface so that an end of the first seal member and an end of the second seal member are pressed against each other by the fastening force of the fastening bolt.

[0014] In this way, a step shape is formed on the mating surface of the side mount bracket such that the end of the first seal member and the end of the second seal member are pressed against each other by the fastening force of the fastening bolt. As a result, by inserting the fastening bolt through the bolt boss portion and fastening it, the first seal member and the second seal member are pressed against each other, ensuring sealing performance. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a diagram showing a timing belt and a belt cover disposed inside the timing belt in an internal combustion engine. [Diagram 2] FIG. 2 is a diagram showing a belt cover disposed on the outside of a timing belt in an internal combustion engine. [Diagram 3] FIG. 2 is a side view of the internal combustion engine showing a state in which the belt cover is assembled. [Figure 4] FIG. 4 is a perspective view of the lower cover as seen from the outside. [Diagram 5] 11 is a perspective view showing a state in which a side mount bracket is attached to a lower cover. FIG. [Figure 6] 13 is a bottom view of the side mount bracket removed from the water pump case. FIG. [Figure 7] FIG. 13 is a perspective view illustrating a configuration in which a side mount bracket is attached to an upper member. [Figure 8] FIG. 11 is a perspective view illustrating the arrangement of a seal member above a side mount bracket. [Figure 9] 4 is a cross-sectional view illustrating a sealing configuration and a fastening configuration above a side mount bracket 8. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] A preferred embodiment of the belt cover structure for an internal combustion engine 1 of the present invention will be described in detail below with reference to the drawings. In this embodiment, the internal combustion engine 1 is described as being vertically mounted. The direction in which the crankshaft 10 and camshafts 11, 12, 13, and 14 of the internal combustion engine 1 extend is referred to as the axial direction, the vertical upward and downward directions are referred to as the up-down direction, and the front-to-rear direction of a vehicle in which the internal combustion engine 1 is vertically mounted is referred to as the front-to-rear direction.

[0017] An outline of the structure of a timing belt TB of an internal combustion engine 1 and the structure of a belt cover of the internal combustion engine 1 will be described with reference to Figures 1 and 2. Figure 1 is a diagram showing the timing belt TB and a belt cover arranged on the inside of the timing belt TB in the internal combustion engine 1. Figure 2 is a diagram showing a belt cover arranged on the outside of the timing belt TB in the internal combustion engine 1. Note that the inside and outside here refer to the side of the timing belt TB that is closer to the cylinder head CH, CH or cylinder block CB of the internal combustion engine 1 as the inside, and the opposite side as the outside.

[0018] As shown in Fig. 1, a crankshaft 10 and camshafts 11, 12, 13, and 14 are disposed to protrude from cylinder heads CH, CH and cylinder block CB on one side of the internal combustion engine 1. The crankshaft 10 and the camshafts 11, 12, 13, and 14 are connected to drive pulleys 15, 16, 17, 18, and 19, respectively. A timing belt TB is stretched around the drive pulleys 15, 16, 17, 18, and 19 and the other pulleys. This causes the crankshaft 10 and the camshafts 11, 12, 13, and 14 to rotate in conjunction with each other.

[0019] As shown in Fig. 1 and Fig. 2, the timing belt TB is protected by a belt cover. The belt cover is attached to one side of the internal combustion engine body and houses the timing belt TB. The belt cover of this embodiment has a front inner cover 2, a rear inner cover 3, an upper outer cover 4, a lower outer cover 5, a rear outer cover 7, a side mount bracket 8, and a lower cover 9. The gaps between the covers are sealed by disposing a seal member or the like. As the gaps between the covers are sealed by disposing a seal member or the like, the belt cover as a whole houses the timing belt TB in a liquid-tight state.

[0020] The procedure for assembling the belt cover of this embodiment will be described with reference to Figures 1 and 2. First, as a premise, as shown in Figure 1, the front inner cover 2 and the rear inner cover 3 are assembled to the cylinder heads CH, CH before the timing belt TB is assembled to the internal combustion engine 1. In addition, the oil pump case OP and the water pump case WP are assembled to one side of the cylinder block CB.

[0021] As shown in FIG. 2, the lower cover 9 is attached so as to cover the periphery of the crankshaft 10, and the side mount bracket 8 is attached so as to be adjacent to the upper side of the lower cover 9. Then, the rear outer cover 7 is attached so as to cover the outside of the drive pulleys 18, 19 of the camshafts 13, 14 and to be adjacent to the upper side of the side mount bracket 8. In addition, the lower outer cover 5 is attached so as to be adjacent to the upper side of the side mount bracket 8, and the upper outer cover 4 is attached so as to be adjacent to the upper side of the lower outer cover 5. Here, the upper outer cover 4 and the lower outer cover 5 together constitute the front outer cover 6 that covers the outside of the drive pulleys 16, 17 of the camshafts 11, 12. The front outer cover 6 is disposed forward of the rear outer cover 7.

[0022] Fig. 3 is a side view of the internal combustion engine 1 showing a state in which the belt cover is attached. As shown in Fig. 3, in a state in which the belt cover is attached, a crank pulley 20 is connected to the crankshaft 10, a pipe 21 is arranged on the outside of the front outer cover 6 and the rear outer cover 7, and a pipe 22 is arranged on the outside of the side mount bracket 8.

[0023] Next, in the belt cover structure of the internal combustion engine 1 of this embodiment, the assembly of the side mount bracket 8 and the lower cover 9 will be described. Fig. 4 is a perspective view of the lower cover 9 as seen from the outside. Fig. 5 is a perspective view showing the state in which the side mount bracket 8 is assembled to the lower cover 9.

[0024] As shown in FIG. 4, a side mount bracket 8 is attached to the outer peripheral surface of the upper end of the lower cover 9 so as to surround the oil pump case OP. and A mating surface 96c is formed between the lower cover 9 and the side mount bracket 8. A lower seal member 41 that seals between the lower cover 9 and the side mount bracket 8 is disposed on the mating surface 96c. In addition, the upper end of the side wall of the lower cover 9 has a protruding portion 94b that protrudes toward the internal combustion engine 1.

[0025] A plurality of vibration suppressing ribs are arranged on the outer surface of the lower cover 9 to increase the rigidity of the lower cover 9 and suppress vibration of the lower cover 9. Four first convex ribs 99b in a fan shape are formed radially on the outer surface of the lower cover 9, centered on the opening 99a of the crankshaft 10. Five second I-shaped convex ribs 99c are arranged on the outer surface of the lower cover 9 so as to be adjacent to the first convex ribs 99b in the circumferential direction. The protruding height of the second convex ribs 99c is formed to be lower than that of the first convex ribs 99b. The second convex ribs 99c provided between these first convex ribs 99b increase the rigidity of the lower cover 9, suppressing the membrane vibration of the lower cover 9 caused by the drive of the crankshaft 10 and the timing belt TB, and suppressing the vibration of the mating surface 96c. Therefore, the sealing property of the mating surface 96c can be maintained without fastening with a separate fastening bolt or the like, and deterioration due to vibration of the lower seal member 41 can also be reduced. The number of each rib is not limited to that of the present embodiment.

[0026] 5, a mating surface 96c of the lower cover 9 is formed on the outer peripheral surface of the upper end of the lower cover 9 so as to surround the oil pump case OP in a direction intersecting the up-down direction (the axial direction away from the internal combustion engine 1 and the front-rear direction). c is , and is fitted to the side mount bracket 8. A lower seal member 41 that seals between the lower cover 9 and the side mount bracket 8 is disposed on the mating surface 96c. The lower seal member 41 is fitted into a recessed groove formed in the mating surface 96c of the lower cover 9.

[0027] The side mount bracket 8 is adjacent to and above the lower cover 9 and is held by the cylinder block CB. The side mount bracket 8 is formed with a mating surface 86c of the side mount bracket 8 that is aligned with a mating surface 96c of the lower cover 9. The mating surface 86c of the side mount bracket 8 is formed on the inner surface of the lower end of the side mount bracket 8. The mating surface 86c of the side mount bracket 8 is configured to cover the mating surface 96c of the lower cover 9 from the outside. In addition, a groove is formed at the upper end of the side mount bracket 8 in which the first upper seal member 51 and a part of the second upper seal member 52 are disposed. The first upper seal member 51 and the second upper seal member 52 will be described later.

[0028] With this configuration, when the side mount bracket 8 is assembled to the lower cover 9, the mating surface 86c of the side mount bracket 8 is fixed in a state in which it is pressed against the mating surface 96c of the lower cover 9 via the lower seal member 41. This fixing is performed by a fastening member such as a fastening bolt (not shown). The lower seal member 41 is made of an elastic member. In this way, the side mount bracket 8 is pressed and fixed against the lower cover 9 in the axial direction, and covers the lower cover 9 from the axial direction and from the left-right direction (front-rear direction) in the figure that intersects with the axial direction.

[0029] The relationship between the side mount bracket 8 and the water pump case WP is shown using Figure 6. Figure 6 is a view from below showing the side mount bracket removed from the water pump case. The water pump case WP is provided with a drive pulley 31 that drives the water pump.

[0030] The side mount bracket 8 is configured so that an end 8a on one side (front) in a width direction (front-rear direction) of the side mount bracket 8, which is a direction perpendicular to the axial direction of the crankshaft 10, covers the water pump case WP. The side mount bracket 8 is configured so that an end 8b on the other side (rear) in the width direction is fixed to an outer surface 37 of the water pump case WP. In this embodiment, a fastening bolt 38 is inserted into a bolt boss portion that passes from the side mount bracket 8 through the water pump case WP to the cylinder block CB, thereby fastening and fixing the side mount bracket 8 and the water pump case WP. However, the fixing method is not limited to this.

[0031] The side mount bracket 8 is moved in the front-to-rear direction when it is attached to or detached from the water pump case WP. Specifically, when attaching the side mount bracket 8 to the water pump case WP, the side mount bracket 8 is moved from the front to the rear and then fixed to the water pump case WP. On the other hand, when removing the side mount bracket 8 from the water pump case WP, the side mount bracket 8 is released from its fixed state and then moved from the rear to the front.

[0032] The difference in axial height (length based on the inner end of the end 8a) of the side mount bracket 8 will now be described. The height H1 of the front end 8a of the side mount bracket 8 is set to a height that covers the front and outer side of the front end 36 of the water pump case WP. On the other hand, the height H2 of the rear end 8b of the side mount bracket 8 is set to the same height as the height H3 of the rear outer surface 37 of the water pump case WP.

[0033] As described above, the rear end 8b of the side mount bracket 8 is fastened and fixed to the rear outer surface 37 of the water pump case WP. Therefore, by increasing the height H3 of the rear outer surface 37 of the water pump case WP, the axial length L1 of the rear end 8b of the side mount bracket 8 can be shortened. Here, the piping 22 is arranged on the outside of the side mount bracket 8 from above to the rear of the side mount bracket 8 ( Figure 3 For this reason, by shortening the axial length L1, the amount of axial movement when attaching and detaching the side mount bracket 8 can be reduced, and the ease of attaching and detaching the side mount bracket 8 can be further improved.

[0034] The assembly configuration above the side mount bracket 8 will be described with reference to Fig. 7. Fig. 7 is a perspective view illustrating the assembly configuration of the side mount bracket 8 to the upper member. Only the front assembly configuration of the side mount bracket 8 and the front outer cover 6, etc. will be described in detail below. However, the rear assembly configuration of the side mount bracket 8 and the rear outer cover 7, rear inner cover 3, etc. is similar in that it is related to the side mount bracket 8, the water pump case WP, and the cylinder block CB.

[0035] A front inner cover 2 that covers the timing belt TB on a side closer to the internal combustion engine 1 than the timing belt TB, and a front outer cover 6 that covers the timing belt TB on a side farther from the internal combustion engine 1 than the timing belt TB are disposed above the side mount bracket 8. In this embodiment, the side mount bracket 8 is fixed to a lower outer cover 5 of the front outer cover 6.

[0036] The front inner cover 2 covers the inside of the camshafts 11, 12 and the drive pulleys 16, 17. The front outer cover 6 covers the periphery of the camshafts 11, 12 and the drive pulleys 16, 17. A water pump case WP is disposed on one axial side surface of the cylinder block CB so as to be adjacent to and below the front inner cover 2. The side mount bracket 8 is disposed on the side farther from the internal combustion engine 1 (outer side) than the water pump case WP so as to cover the water pump case WP.

[0037] The sealing configuration above the side mount bracket 8 will be described with reference to Figures 8 and 9. Figure 8 is a perspective view illustrating the arrangement of seal members 51, 52 above the side mount bracket 8. Figure 9 is a cross-sectional view illustrating the sealing configuration and fastening configuration above the side mount bracket 8. As above, only the configuration above the front side will be described, but the configuration above the rear side is similar.

[0038] 8 and 9, the side mount bracket 8 has a first upper seal member 51 and a part of the second upper seal member 52 disposed on a mating surface 81 at its upper end. A groove is formed in the mating surface 81 for fitting the first upper seal member 51 and a part of the second upper seal member 52. The first upper seal member 51 is a member that seals between the front outer cover 6 and the side mount bracket 8, and the second upper seal member 52 is a member that seals between the front inner cover 2 and the water pump case WP and the inner end of the side mount bracket 8. The first upper seal member 51 and the second upper seal member 52 are made of elastic members.

[0039] The end 51a of the first upper seal member 51 and the end 52a of the second upper seal member 52 are arranged so as to be pressed against each other. Specifically, the second upper seal member 52 is configured to rise upward from a position lower than the height of the first upper seal member 51 along a step shape 81a formed on the upper mating surface 81 of the side mount bracket 8. The step shape 81a is configured so that the position where the first upper seal member 51 is arranged is higher than the position where the second upper seal member 52 is arranged in the portion where the step is formed. As a result, the end 51a of the first upper seal member 51 comes into contact with the end 52a of the second upper seal member 52. In addition, the end 51a of the first upper seal member 51 and the end 52a of the second upper seal member 52 are fastened and fixed by the fastening bolt 61 in the direction in which they abut (front-rear direction). Due to the fastening force of the fastening bolt 61, the end 51a of the first upper seal member 51 is pressed against the end 52a of the second upper seal member 52, and the end 51a of the first upper seal member 51 and the end 52a of the second upper seal member 52 are pressed against each other.

[0040] 9, the side mount bracket 8, the water pump case WP, and the cylinder block CB are formed with communicating bolt boss portions 62 for inserting fastening bolts 61. The mating surface 81 of the side mount bracket 8 is formed at the upper end portion near the bolt boss portions 62, and is formed across the front inner cover 2 and the front outer cover 6. This allows the end portion 51a of the first upper seal member 51 that seals the front outer cover 6 to be adjacent to the end portion 52a of the second upper seal member 52 that seals the front inner cover 2.

[0041] Furthermore, because the mating surface 81 is formed in the vicinity of the bolt boss portion 62, the step shape 81a formed on the mating surface 81 is located above the position where the first upper seal member 51 is disposed relative to the position where the second upper seal member 52 is disposed. Here, the bolt boss portion 62 through which the fastening bolt 61 is inserted is formed below the position of the step shape 81a, so that the length L2 from the bolt boss portion 62 to the upper end of the side mount bracket 8 can be configured to be longer than the length from the bolt boss portion 62 to the water pump case WP. Because the fastening bolt 61 is inserted from the side mount bracket 8, the rigidity of the side mount bracket 8 at the fastening portion can be ensured.

[0042] As described above, according to the present embodiment, the mating surface 86c of the side mount bracket 8 is configured to cover the mating surface 96c of the lower cover 9 from the outside, and the side mount bracket 8 and the lower cover 9 adjacent in the vertical direction are fixed in a direction intersecting the vertical direction. As a result, when removing the side mount bracket 8 from the lower cover 9, it can be removed in a direction intersecting the vertical direction. In this case, even if it is difficult to remove the side mount bracket 8 in the upward direction because another cover (front outer cover 6 or rear outer cover 7) is arranged above the side mount bracket 8, the side mount bracket 8 can be easily removed. In addition, the lower cover 9 and the side mount bracket 8 are fixed in a state of being pressed against each other via the lower seal member 41. Thus, it is possible to provide a belt cover for an internal combustion engine 1 that is easy to attach and detach and has a sealability.

[0043] Furthermore, according to this embodiment, in a configuration in which the side mount bracket 8 is moved rearward during installation and moved forward during removal, the rear end 8b of the side mount bracket 8 is fixed to the outer surface 37 of the water pump case WP. As a result, when the side mount bracket 8 is attached or detached, the rear end 8b of the side mount bracket 8 moves less in the axial direction compared to when the rear end 8b covers the water pump case WP like the front end 8a. This makes it possible to easily attach and detach the side mount bracket 8.

[0044] According to this embodiment, the first upper seal member 51 that seals between the front outer cover 6 and the side mount bracket 8 and the second upper seal member 52 that seals between the front inner cover 2 and the side mount bracket 8 are arranged so as to be pressed against each other at their ends 51a, 52a. This ensures sealing between the first upper seal member 51 and the second upper seal member 52. The water pump case WP is also covered by the side mount bracket 8. This allows the water pump to be easily attached and detached during maintenance by removing the side mount bracket 8 without removing the lower cover 9. This makes it possible to provide a belt cover for an internal combustion engine 1 that is easy to attach and detach and has sealing properties.

[0045] Furthermore, according to this embodiment, a step shape 81a is formed on the mating surface 81 of the side mount bracket 8 such that the end 51a of the first upper seal member 51 and the end 52a of the second upper seal member 52 are pressed against each other by the fastening force of the fastening bolt 61. As a result, by inserting the fastening bolt 61 through the bolt boss portion 62 and fastening it, the first upper seal member 51 and the second upper seal member 52 are pressed against each other, ensuring sealing performance.

[0046] The present invention is not limited to the embodiment described above, and can be embodied in various forms. In the above embodiment, the timing belt TB is used as a transmission belt for transmitting drive from the crankshaft 10 to the camshafts 11, 12, 13, and 14, but the present invention is not limited to this. For example, as an example of the transmission structure of the internal combustion engine 1, a chain transmission mechanism may be used in which a transmission belt made of a timing chain is stretched between a crankshaft driving wheel and a camshaft driven wheel made of a sprocket. [Explanation of symbols]

[0047] 1. Internal combustion engine 2...Front inner cover (upper inner cover part) 6...Front outer cover (outer cover member, upper outer cover member) 8…Side mount bracket 8a, 8b...ends 9...Lower cover (outer cover member, lower outer cover member) 41...Lower seal member 51...First upper seal member (first seal member) 52...Second upper seal member (second seal member) 51a, 52a...ends 61... Fastening bolt 62...Bolt boss part 81…Mating surface 81a…Step shape 86c…Mating surface 96c…Mating surface CB: Cylinder block (internal combustion engine body) OP…Oil pump case (inner cover material) TB…Timing belt WP…Water pump case

Claims

1. A belt cover structure for an internal combustion engine, which is disposed on one side of an internal combustion engine body and accommodates at least a part of a timing belt that transmits power between a crankshaft and a camshaft, an inner cover member that covers the timing belt on a side closer to the internal combustion engine than the timing belt; an outer cover member that covers the timing belt on a side farther from the internal combustion engine than the timing belt, The outer cover member has at least a lower outer cover member that covers the periphery of the crankshaft, a side mount bracket held by the internal combustion engine body is disposed adjacent to and above the lower outer cover member; The lower outer cover member and the side mount bracket each have a mating surface that can be mated with each other, a lower seal member that seals the lower outer cover member and the side mount bracket is disposed on a mating surface of the lower outer cover member; a mating surface of the side mount bracket is configured to cover a mating surface of the lower outer cover member from the outside, the lower outer cover member and the side mount bracket are fixed in a state in which a mating surface of the side mount bracket is pressed against a mating surface of the lower outer cover member via the lower seal member, A water pump case is disposed on the one side surface of the internal combustion engine body, the side mount bracket is configured such that one end in a width direction perpendicular to an axial direction of the crankshaft covers the water pump case, and the other end in the width direction is fixed to an outer surface of the water pump case, a side mount bracket disposed on one side of the belt cover and disposed on the other side of the belt cover, the side mount bracket being moved to the other side when the side mount bracket is attached, and the side mount bracket being moved to the one side when the side mount bracket is removed.

2. A belt cover structure for an internal combustion engine, which is disposed on one side of an internal combustion engine body and accommodates at least a part of a timing belt that transmits power between a crankshaft and a camshaft, an inner cover member that covers the timing belt on a side closer to the internal combustion engine than the timing belt; an outer cover member that covers the timing belt on a side farther from the internal combustion engine than the timing belt, The inner cover member has at least an upper inner cover member that covers the periphery of the camshaft, The outer cover member has at least an upper outer cover member that covers the periphery of the camshaft, a water pump case is disposed on the one side surface of the internal combustion engine body so as to be adjacent to and below the upper inner cover member, a side mount bracket for covering the water pump case is disposed on a side farther from the internal combustion engine than the water pump case; the upper outer cover member is fixed to the upper part of the side mount bracket via a first seal member provided on the side mount bracket, the upper inner cover member is fixed to an upper portion of the side mount bracket and an upper portion of the water pump case via a second seal member provided on the side mount bracket, A belt cover structure for an internal combustion engine, characterized in that an end portion of the first seal member and an end portion of the second seal member are arranged so as to be in pressure contact with each other.

3. The side mount bracket and the water pump case are formed with bolt bosses for inserting fastening bolts therethrough so as to communicate with each other, the side mount bracket has a mating surface that is mated across the upper inner cover member and the upper outer cover member in the vicinity of the bolt boss portion, 3. The belt cover structure for an internal combustion engine as described in claim 2, characterized in that the mating surface is formed in a stepped shape so that the end of the first seal member and the end of the second seal member are pressed against each other by the fastening force of the fastening bolt.

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