Cooling water drainage structure

Abstract

To suppress a deterioration in engine appearance due to attachment of deposits from cooling water.SOLUTION: A cooling water drainage structure is provided with: an engine cover (42) attached to a crank case (31); and a water pump (43) attached to the engine cover. The water pump is mounted with a seal member (56) for sealing a pump chamber (55), and has a water drain hole (65) for draining cooling water leaked from the seal member formed therein. In the engine cover, there are formed a drain passage (66) for guiding the cooling water to a lower surface of the engine cover from the water drain hole and a cover part (71) for covering a lower space of an outlet (67) of the drain passage by extending from the lower surface of the engine cover. The cover part has: a side wall (72) covering the lower space from an outside in a vehicle width direction; and a bottom wall (73) covering the lower space from a lower side.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a drainage structure for cooling water. [Background technology]

[0002] Water-cooled engines generally have a circulation flow path through which coolant from a water pump returns to the water pump via a water jacket in the cylinder and a radiator. While a mechanical seal is installed in the water pump, it is difficult to completely prevent water leakage from the water pump using only a mechanical seal. For this reason, water pumps are provided with a drainage structure for coolant that leaks from the mechanical seal (see, for example, Patent Document 1). The pump case of the water pump described in Patent Document 1 has a drainage hole, through which coolant that leaks from the mechanical seal is discharged to the outside of the case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3558164 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the water pump described in Patent Document 1 has a problem in that the coolant discharged from the drain hole adheres to the engine case and cover, and deposits of the coolant deteriorate the appearance of the engine.

[0005] The present invention has been made in view of the above points, and has as its object to provide a cooling water drainage structure that can prevent deterioration of the engine appearance due to the adhesion of cooling water deposits. [Means for solving the problem]

[0006] One aspect of the present invention provides a cooling water drainage structure comprising an engine cover attached to a crankcase and a water pump attached to the engine cover, wherein the water pump is fitted with a sealing member that seals a pump chamber and has a drain hole formed therein to discharge cooling water that leaks from the sealing member, and the engine cover is formed with a drain passage that directs cooling water from the drain hole to the underside of the engine cover, and a covering portion that extends from the underside of the engine cover and covers the space below the outlet of the drain passage, and the covering portion has side walls that cover the lower space from the outside in the vehicle width direction and a bottom wall that covers the lower space from below, thereby solving the above-mentioned problem. [Effects of the Invention]

[0007] According to one aspect of the coolant drainage structure of the present invention, when a leak occurs in the seal member of the water pump, the coolant is guided from the drain hole of the water pump to the outlet of the drain passage. The coolant is discharged from the outlet of the drain passage, but is received by the side walls and bottom wall of the covering portion, preventing the coolant from spreading along the outside of the engine cover. When the engine is running, the heat of the engine makes it easy for the coolant in the covering portion to evaporate. Therefore, even if the water pump is attached to the engine cover, water leakage from the water pump is hidden by the covering portion, preventing a deterioration in the appearance of the engine. Furthermore, because the covering portion extends from the underside of the engine cover, the covering portion is less noticeable and coolant is less likely to adhere to other components. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a right side view of the saddle-ride type vehicle of the present embodiment. [Figure 2] FIG. 2 is a right side view of the engine of the present embodiment. [Figure 3] FIG. 2 is a front view of the engine of the present embodiment. [Figure 4] FIG. 3 is a cross-sectional view of the engine of FIG. 2 taken along line AA. [Figure 5] FIG. 4 is a cross-sectional view of the engine of FIG. 3 taken along line BB. [Figure 6] FIG. 2 is an enlarged view of the periphery of a covering portion of the present embodiment. [Figure 7] FIG. 2 is an explanatory diagram of a drainage path in this embodiment. [Figure 8] FIG. 10 is a diagram showing a cooling water drainage structure of a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0009] In one aspect of the present invention, an engine includes an engine cover attached to a crankcase, and a water pump attached to the engine cover. In a coolant drainage structure, a seal is attached to the water pump to seal a pump chamber, and coolant leaking from the seal is discharged through a drain hole in the water pump. A drain passage in the engine cover guides the coolant from the drain hole to the underside of the engine cover, and a covering portion extending from the underside of the engine cover covers a space below the outlet of the drain passage. The side walls of the covering portion cover the lower space from the outside in the vehicle width direction, and the bottom wall of the covering portion covers the lower space from below. When water leaks from the seal of the water pump, the coolant is guided from the drain hole in the water pump to the outlet of the drain passage. The coolant is discharged from the drain passage outlet, but is caught by the side walls and bottom wall of the covering portion, preventing the coolant from spreading along the outside of the engine cover. During engine operation, the heat of the engine easily evaporates the coolant in the covering portion. Therefore, even if a water pump is attached to the engine cover, water leakage from the water pump will be hidden by the covering portion, and the appearance of the engine will not be impaired. Also, because the covering portion extends from the underside of the engine cover, the covering portion is less noticeable and cooling water is less likely to adhere to other parts. [Example]

[0010] A saddle-ride type vehicle provided with a cooling water drainage structure of this embodiment will be described below with reference to the accompanying drawings. Fig. 1 is a right side view of the saddle-ride type vehicle of this embodiment. In the following drawings, arrow FR indicates the front of the vehicle, arrow RE indicates the rear of the vehicle, arrow L indicates the left side of the vehicle, and arrow R indicates the right side of the vehicle.

[0011] As shown in Fig. 1, a saddle-type vehicle 1 is configured by mounting various parts such as an engine 30 and an electrical system on a body frame 10. A pair of main frames 12 extend diagonally downward and rearward from a head pipe (not shown) of the body frame 10, and the rear portions of the pair of main frames 12 bend downward to form a pair of body frames 13. In addition, down frames 14 extend downward from the head pipe, and under loops 15 bent rearward are connected to the lower portions of the down frames 14. The rear ends of the pair of under loops 15 are connected to the lower portions of the pair of body frames 13, and the body frame 10 is formed into a cradle shape.

[0012] A front fork 17 is supported on the head pipe via a steering shaft (not shown) so as to be steerable. Handlebars 18 are provided on the upper part of the front fork 17, and a front wheel 19 is rotatably supported on the lower part of the front fork 17. A fuel tank 21 is placed on the upper part of the pair of main frames 12, and the main frames 12 and fuel tank 21 are covered from the sides by front side covers 22. A seat 23 is installed behind the fuel tank 21, and a seat frame (not shown) that supports the seat 23 from below is covered from the sides by rear side covers 24.

[0013] A swing arm 25 is swingably supported by the body frame 13. The swing arm 25 extends rearward from the body frame 13, and a rear wheel 26 is rotatably supported at the rear end of the swing arm 25. The engine 30 is a four-stroke single-cylinder engine, and is suspended inside the body frame 10 via multiple suspension brackets. A cylinder assembly, which is made up of a stacked cylinder 32, a cylinder head 33, and a cylinder head cover 34, is attached to the top of a crankcase 31 of the engine 30. An air cleaner 35 is installed behind the cylinder head 33.

[0014] An exhaust pipe 36 extends downward from the left front side of the cylinder head 33, passes along the right side of the cylinder 32 and connects to a muffler 37 at the rear of the vehicle. Left and right radiators (not shown) are attached to the front of the cylinder head 33. A clutch cover 42 is attached to the right side of the crankcase 31, and a water pump 43 is attached to the outer surface of the clutch cover 42. Cooling water is sent from the water pump 43 to a cooling passage in the crankcase 31 and returned to the water pump 43 via the cylinder 32, water jackets in the cylinder head 33, and the radiator.

[0015] In a typical water pump, the pump chamber is sealed with a mechanical seal, but it is difficult to completely prevent water leakage using a mechanical seal alone. Therefore, a drain hole is formed in the water pump, and a drain passage connected to the drain hole is formed in the clutch cover. If cooling water leaks from the water pump's mechanical seal, the cooling water enters the drain passage in the clutch cover through the water pump's drain hole and is discharged to the outside of the clutch cover through the drain passage's outlet. However, if the cooling water runs down the outside of the clutch cover, deposits from the cooling water will adhere to the clutch cover, deteriorating the engine's appearance.

[0016] In this case, it is possible to attach a nipple to the outlet of the drain passage and extend a hose from the nipple to below the engine, but the need for nipples and hoses increases the number of parts and costs. Also, depending on the configuration of the engine and frame, there is a risk that the nipple may interfere with the frame when the engine is installed and be damaged, or that it may be damaged by flying stones. To prevent damage to the nipple, it is possible to configure the tip of the nipple to point inward in the vehicle width direction from the clutch cover, but this would require bending the drain passage inside the clutch cover, increasing the number of processing steps and the need for blind plugs, which would increase costs.

[0017] Therefore, in the water pump 43 of this embodiment, instead of providing a nipple at the outlet of the drain passage, a covering portion 71 (see FIG. 2) extends from the clutch cover 42 so as to cover the space below the outlet of the drain passage. Coolant is discharged from the outlet of the drain passage inside the clutch cover 42 to the inside of the covering portion 71, and even if the amount of coolant is small, it is collected inside the covering portion 71 and evaporated by the heat of the engine 30. Therefore, even if the water pump 43 is attached to the clutch cover 42, the coolant is less likely to spread along the outside of the clutch cover 42, and the appearance of the engine is not impaired by coolant deposits or the like.

[0018] The engine of this embodiment will be described with reference to Figures 2 to 5. Figure 2 is a right side view of the engine of this embodiment. Figure 3 is a front view of the engine of this embodiment. Figure 4 is a cross-sectional view of the engine of Figure 2 taken along line AA. Figure 5 is a cross-sectional view of the engine of Figure 3 taken along line BB.

[0019] 2 and 3, the engine 30 has a crankcase 31 with a split structure consisting of a pair of left and right case halves. A cylinder 32 is attached to the top surface of the crankcase 31, a cylinder head 33 is attached to the top surface of the cylinder 32, and a cylinder head cover 34 is attached to the top surface of the cylinder head 33. A starter motor 38 is also attached to the top surface of the crankcase 31, behind the cylinder 32. A magneto cover 41 is attached to the left side of the crankcase 31, and a clutch cover (engine cover) 42 is attached to the right side of the crankcase 31.

[0020] The rear half of the clutch cover 42 bulges outward in the vehicle width direction, forming a cylindrical shape, while the front half of the clutch cover 42 has a vertical dimension that decreases toward the front. The upper surface of the front half of the clutch cover 42 slopes downward toward the front, while the lower surface of the front half of the clutch cover 42 slopes upward toward the front. An oil filter cover 44 and a water pump 43 are attached to the outer surface of the front half of the clutch cover 42. Below the water pump 43, the lower surface of the clutch cover 42 slopes, and a covering portion 71, described below, extends downward from the slope of this clutch cover 42.

[0021] 4 and 5, a pump case 51 of the water pump 43 is fixed in a mounting hole 45 of the clutch cover 42. A cylindrical portion 52 of the pump case 51 fits inside the clutch cover 42, and a flange portion 53 of the pump case 51 is located outside the clutch cover 42. A pump cover 54 of the water pump 43 is attached to the flange portion 53 of the pump case 51, and a pump chamber 55 through which cooling water flows is formed by the pump cover 54 and the flange portion 53. A mechanical seal (sealing member) 56 is attached to the outer side of the cylindrical portion 52 of the pump case 51 in the vehicle width direction, and the pump chamber 55 is sealed by the mechanical seal 56.

[0022] A pair of bearings 57, 58 are provided on the inner side in the vehicle width direction of the cylindrical portion 52 of the pump case 51, and an impeller shaft 61 is rotatably supported by the pair of bearings 57, 58. An oil seal 59 is attached to the middle part in the vehicle width direction of the cylindrical portion 52 of the pump case 51, and the oil seal 59 seals the gap between the impeller shaft 61 and the cylindrical portion 52. The impeller shaft 61 passes inside the mechanical seal 56 and extends from inside the crankcase 31 into the pump chamber 55. An impeller 62 is fixed to one end of the impeller shaft 61 inside the pump chamber 55, and a gear 63 is fixed to the other end of the impeller shaft 61 inside the crankcase 31.

[0023] A space 64 is provided between the mechanical seal 56 and the oil seal 59, and cooling water that leaks from the mechanical seal 56 is received in the space 64. The cooling water leaks only to a trickle as long as the mechanical seal 56 is not damaged. A drain hole 65 that communicates with the space 64 is formed in the lower part of the cylindrical portion 52 of the pump case 51, and the cooling water is discharged through the drain hole 65, preventing the cooling water from mixing with the oil. The impeller shaft 61 is positioned at approximately the same height as the crankshaft 39, and the clutch cover 42 is formed with a drain passage 66 that guides the cooling water from the drain hole 65 below the impeller shaft 61 to the underside of the clutch cover 42.

[0024] An outlet 67 of the drain passage 66 opens on the underside of the clutch cover 42, and a covering portion 71 extends from the underside of the clutch cover 42 to cover the space below the outlet 67 of the drain passage 66. The cooling water is caught by the covering portion 71, making it less likely for the cooling water to spread down the clutch cover 42. The covering portion 71 has side walls 72 that cover the lower space from the outside in the vehicle width direction, a bottom wall 73 that covers the lower space from below, a front wall 74 that covers the lower space from the front side, and a rear wall 75 that covers the lower space from the rear side. The covering portion 71 is formed into a box shape with an open inner surface on the inside in the vehicle width direction by the underside of the clutch cover 42, the side walls 72, the bottom wall 73, the front wall 74, and the rear wall 75.

[0025] Clutch cover 42 is attached to crankcase 31 via gasket 77, and the opening on the inner surface of covering portion 71 is blocked by gasket 77 between clutch cover 42 and crankcase 31. In this case, a pressing portion 80 for gasket 77 is formed in the lower part of crankcase 31 in correspondence with covering portion 71, and gasket 77 is pressed against covering portion 71 by pressing portion 80 so that the lower space is blocked from the inside in the vehicle width direction by gasket 77. Cooling water is received by side walls 72, bottom wall 73, front wall 74, rear wall 75, and gasket 77 of covering portion 71, making it difficult for the cooling water to spread along the outside of clutch cover 42.

[0026] A drain hole 76 is formed in the bottom wall 73 of the covering portion 71, and the outlet 67 of the drain passage 66 and the drain hole 76 are positioned in a straight line. If the mechanical seal 56 leaks only a small amount of coolant, the leak is received by the covering portion 71, but if the mechanical seal 56 is damaged and a large amount of water leaks, the water is drained through the drain hole 76. A malfunction of the mechanical seal 56 can be detected by the amount of coolant drained through the drain hole 76. Furthermore, the outlet 67 of the drain passage 66 and the drain hole 76 being positioned in a straight line allows for smooth drainage. Furthermore, the drain passage 66 and the drain hole 76 can be easily machined when manufacturing the clutch cover 42.

[0027] The cooling water drainage structure will be described with reference to Figures 6 and 7. Figure 6 is an enlarged view of the periphery of the covering portion of this embodiment, and Figure 7 is an explanatory view of the drainage path of this embodiment.

[0028] 6 and 7, the underside of the clutch cover 42 slopes higher toward the front below the water pump 43. A drain passage 66 extends linearly from a drain hole 65 in the water pump 43 to the underside of the clutch cover 42, and a covering portion 71 protrudes from the underside of the clutch cover 42 in the extension direction of the drain passage 66. A front wall 74 and a rear wall 75 of the covering portion 71 protrude perpendicularly from the underside of the clutch cover 42, and the distance between the front wall 74 and the rear wall 75 is formed to be larger than the diameter of the outlet 67 of the drain passage 66. The covering portion 71 widely covers the space below the outlet 67 of the drain passage 66, making it easy to conceal water leaks.

[0029] The covering portion 71 extends in the vehicle width direction, and an end face 78 on the inner side in the vehicle width direction of the covering portion 71 is formed flush with a mating surface 79 of the clutch cover 42 that fits against the crankcase 31. Cooling water dripping from the outlet 67 of the drain passage 66 is received by the covering portion 71, making it difficult for the cooling water to spread along the outside of the clutch cover 42. A bottom wall 73 of the covering portion 71 is parallel to the underside of the clutch cover 42 and is inclined so that the bottom wall 73 becomes higher toward the front. A drain hole 76 that is larger than the outlet 67 of the drain passage 66 is formed in the bottom wall 73 of the covering portion 71. The drain hole 76 is positioned on an extension of the drain passage 66 and faces the outlet 67 of the drain passage 66.

[0030] When the underside of clutch cover 42, which forms the upper wall of covering portion 71, is divided into a high side and a low side, outlet 67 of drain passage 66 opens in the front half of the underside of clutch cover 42, which is the high side. Furthermore, when bottom wall 73 of covering portion 71 is divided into a high side and a low side, drain hole 76 opens in the front half of bottom wall 73, which is the high side of bottom wall 73. The rear half of covering portion 71, which is the low side of bottom wall 73, functions as a water receiver, and if there is only a small amount of water leakage from mechanical seal 56, cooling water will accumulate in the rear half of covering portion 71, forming pool 81. When the engine is running, the heat of the engine causes the cooling water to evaporate, making it difficult for the cooling water to be discharged to the underside of clutch cover 42.

[0031] In this embodiment, the water pump 43 and clutch cover 42 are located on the right side of the vehicle body, and the side stand 27 (see FIG. 1), which tilts the vehicle body to support it, is located on the left side of the vehicle body. In other words, the covering portion 71 formed on the clutch cover 42 is located on the opposite side of the vehicle width from the side stand 27. Because the vehicle body is tilted to the left when parking, the covering portion 71 on the right side of the vehicle body is positioned higher, making it difficult for coolant to drain from the drain hole 76. Because the covering portion 71 is provided on the lower part of the clutch cover 42, even if the vehicle body is tilted on the side stand 27 and the clutch cover 42 side is raised, the covering portion 71 is less noticeable, improving the appearance.

[0032] In this type of coolant drainage structure, as shown by arrow A, when coolant seeps through mechanical seal 56 of water pump 43, the coolant enters drain passage 66 from space 64 between mechanical seal 56 and oil seal 59 through drain hole 65. From outlet 67 of drain passage 66, the coolant flows down the underside of clutch cover 42 and into the inside of covering portion 71, then flows down side wall 72, rear wall 75, and wall surface of gasket 77 of covering portion 71, and accumulates in the rear half of covering portion 71. Because the amount of water leakage from mechanical seal 56 is small, a liquid pool 81 is formed without being drained from drain hole 76 even if the inclination of bottom wall 73 is shallow.

[0033] As shown by arrow B, when the mechanical seal 56 is damaged and a large amount of cooling water is discharged, the cooling water flows from the space 64 between the mechanical seal 56 and the oil seal 59 through the drain hole 65 into the drain passage 66. The cooling water flows into the inside of the covering portion 71 from the outlet 67 of the drain passage 66, and a large amount of cooling water is discharged from the drain hole 76 through the inside of the covering portion 71. At this time, the outlet 67 of the drain passage 66 and the drain hole 76 are arranged in a straight line, and the drain hole 76 is larger than the outlet 67 of the drain passage 66, so the cooling water is discharged smoothly from the drain hole 76. The large amount of discharged cooling water can be detected as a malfunction of the mechanical seal 56.

[0034] As described above, according to the coolant drainage structure of this embodiment, if water leaks from the mechanical seal 56 of the water pump 43, the coolant will enter the drain passage 66 through the drain hole 65 of the water pump 43. The coolant is discharged from the outlet 67 of the drain passage 66, but is caught by the covering portion 71, preventing the coolant from spreading along the outside of the clutch cover 42. When the engine is running, the heat of the engine 30 causes the coolant in the covering portion 71 to evaporate easily. Therefore, even if the water pump 43 is attached to the clutch cover 42, water leakage from the water pump 43 is hidden by the covering portion 71, preventing a deterioration in the appearance of the engine 30. Furthermore, because the covering portion 71 extends from the underside of the clutch cover 42, the covering portion 71 is less noticeable and the coolant is less likely to adhere to other components.

[0035] 8, the gasket 77 may be folded to form a partition wall 82 that separates the inside of the covering portion 71 into upper and lower sections, and the outlet 67 of the drain passage 66 may be covered from below by the partition wall 82 of the gasket 77. The cooling water dripping from the outlet 67 of the drain passage 66 is received by the partition wall 82 of the gasket 77, and a simple labyrinth structure is formed inside the covering portion 71, making it difficult for the cooling water to be discharged along the outside of the clutch cover 42.

[0036] Furthermore, in this embodiment, the covering portion is formed in a box shape, but the covering portion may have any shape as long as it can cover the space below the outlet of the drain passage.

[0037] Furthermore, in this embodiment, the outlet of the drain passage and the drain hole are arranged on a straight line, but the outlet of the drain passage and the center of the drain hole may be offset.

[0038] In this embodiment, the side shape of the pressing portion may or may not match the side shape of the covering portion. The pressing portion may be formed so as to be able to press the gasket against the covering portion, and may be formed, for example, in a rib shape.

[0039] The cooling water drainage structure of this embodiment is not limited to the saddle-ride type vehicle described above, and may be adopted in other types of saddle-ride type vehicles. Note that the saddle-ride type vehicle is not limited to all vehicles in which the rider sits astride on the seat, but also includes scooter-type vehicles in which the rider does not sit astride on the seat.

[0040] As described above, the first aspect is a cooling water drainage structure including an engine cover (clutch cover 42) attached to the crankcase (31) and a water pump (43) attached to the engine cover, in which the water pump is fitted with a sealing member (mechanical seal 56) that seals a pump chamber (55) and has a drain hole (65) for discharging cooling water leaking from the sealing member, and the engine cover is formed with a drain passage (66) that directs cooling water from the drain hole to the underside of the engine cover and a covering portion (71) that extends from the underside of the engine cover and covers a space below an outlet (67) of the drain passage, the covering portion having a side wall (72) that covers the lower space from the outside in the vehicle width direction and a bottom wall (73) that covers the lower space from below. With this configuration, if water leaks from the sealing member of the water pump, cooling water will enter the drain passage through the drain hole of the water pump. Coolant discharged from the drain passage outlet is captured by the side and bottom walls of the covering, preventing it from spreading along the outside of the engine cover. When the engine is running, the heat from the engine makes it easier for the coolant inside the covering to evaporate. Therefore, even if a water pump is attached to the engine cover, water leakage from the water pump is hidden by the covering, preventing the engine's appearance from being impaired. Furthermore, because the covering extends from the underside of the engine cover, the covering is less noticeable and coolant is less likely to adhere to other components.

[0041] In the second aspect, the covering portion of the first aspect has a front wall (74) that covers the lower space from the front side and a rear wall (75) that covers the lower space from the rear side, and the distance between the front and rear walls of the covering portion is formed larger than the diameter of the outlet of the drain passage. With this configuration, the covering portion widely covers the space below the outlet of the drain passage, making it easy to conceal water leakage. In addition, the cooling water is received by the front and rear walls of the covering portion, making it difficult for the cooling water to spread along the outside of the engine cover.

[0042] In a third aspect, in the first or second aspect, the covering portion extends in the vehicle width direction and is formed so that the inner end face of the covering portion in the vehicle width direction is flush with the mating surface of the engine cover against the crankcase. With this configuration, the cooling water dripping from the outlet of the drain passage is received by the bottom wall of the covering portion, making it difficult for the cooling water to spread along the outside of the engine cover.

[0043] In a fourth aspect, in any one of the first to third aspects, an engine cover is attached to the crankcase via a gasket (77), and the gasket is pressed against the covering portion so that the lower space is blocked from the inside in the vehicle width direction by the gasket. With this configuration, the cooling water dripping from the outlet of the drain passage is received by the gasket, and the cooling water is less likely to spread along the outside of the engine cover.

[0044] A fifth aspect is any one of the first to fourth aspects, in which a drain hole is formed in the bottom wall of the covering portion, and the outlet of the drain passage and the drain hole are aligned in a straight line. With this configuration, if the seal member is damaged and a large amount of water leaks, the water is drained through the drain hole, and a malfunction of the seal member can be detected based on the amount of coolant drained from the drain hole. In addition, since the outlet of the drain passage and the drain hole are aligned in a straight line, water can be drained smoothly. Furthermore, the drain passage and the drain hole can be easily machined when manufacturing the engine cover.

[0045] In a sixth aspect, when the bottom wall of the covering part is divided into a high side and a low side in the fifth aspect, the drain hole opens on the high side of the bottom wall of the covering part. With this configuration, the cooling water is easily accumulated inside the covering part, and the cooling water inside the covering part is less likely to evaporate due to the heat of the engine when the engine is running, and is less likely to be discharged into the engine cover.

[0046] In a seventh aspect, in any one of the first to sixth aspects, the covering portion is located on the opposite side of the vehicle width direction from the side stand (27) that tilts the vehicle body to support it. With this configuration, cooling water is less likely to leak from the covering portion when parked. Because the covering portion is provided under the engine cover, even if the vehicle body is tilted on the side stand and the engine cover side becomes higher, the covering portion is less noticeable, improving the appearance.

[0047] An eighth aspect is any one of the first to seventh aspects, in which the engine cover is attached to the crankcase via a gasket, the gasket is folded to form a partition wall (82) that separates the inside of the covering portion into upper and lower sections, and the outlet of the drain passage is covered from below by the partition wall of the gasket. With this configuration, cooling water dripping from the outlet of the drain passage is received by the partition wall of the gasket, and a simple labyrinth structure is formed inside the covering portion, making it difficult for the cooling water to be discharged to the outside of the engine cover.

[0048] Although the present embodiment has been described, other embodiments may be made by combining the above-described embodiments and modifications in whole or in part.

[0049] Furthermore, the technology of the present invention is not limited to the above-described embodiments, and various changes, substitutions, and modifications may be made without departing from the spirit of the technical idea. Furthermore, if the technical idea can be realized in a different way due to technological advances or other derived technologies, it may be implemented using that method. Therefore, the claims cover all embodiments that may fall within the scope of the technical idea. [Explanation of symbols]

[0050] 31: Crankcase 42: Clutch cover (engine cover) 43: Water pump 55: Pump room 56: Mechanical seal (sealing material) 65: Drain hole 66: Drain passage 67: Drain passage exit 71: Covering part 72: Side wall 73: Bottom wall 74: Front wall 75: Back wall 76: Drain hole 77: Gasket 78: End face 79:Mating surface 82: Bulkhead

Claims

1. A cooling water drainage structure including an engine cover attached to a crankcase and a water pump attached to the engine cover, The water pump is fitted with a seal member that seals a pump chamber, and is formed with a drain hole that discharges cooling water that leaks from the seal member. The engine cover is formed with a drain passage that guides cooling water from the drain hole to the underside of the engine cover, and a covering portion that extends from the underside of the engine cover and covers a space below an outlet of the drain passage, The cooling water drainage structure, characterized in that the covering portion has a side wall that covers the lower space from the outside in the vehicle width direction, and a bottom wall that covers the lower space from below.

2. the covering portion has a front wall that covers the lower space from a front side and a rear wall that covers the lower space from a rear side, 2. The cooling water drainage structure according to claim 1, wherein the distance between the front wall and the rear wall of the covering portion is formed larger than the diameter of the outlet of the drain passage.

3. 3. A cooling water drainage structure as described in claim 1 or claim 2, characterized in that the covering portion extends in the vehicle width direction, and the end face of the covering portion on the inner side in the vehicle width direction is formed so as to be flush with the mating surface of the engine cover against the crankcase.

4. The engine cover is attached to the crankcase via a gasket, 3. The cooling water drainage structure according to claim 1, wherein the gasket is pressed against the covering portion so that the lower space is closed by the gasket from the inside in the vehicle width direction.

5. 3. The cooling water drainage structure according to claim 1, wherein a drain hole is formed in the bottom wall of the covering portion, and the outlet of the drain passage and the drain hole are arranged on a straight line.

6. 6. The cooling water drainage structure according to claim 5, wherein when the bottom wall of the covering portion is divided into a higher side and a lower side, the drain hole opens to the higher side of the bottom wall of the covering portion.

7. 3. The cooling water drainage structure according to claim 1, wherein the covering portion is located on the opposite side in the vehicle width direction to a side stand that tilts the vehicle body and allows it to stand upright.

8. The engine cover is attached to the crankcase via a gasket, 3. A cooling water drainage structure as described in claim 1 or claim 2, characterized in that the gasket is folded to form a partition wall that divides the inside of the covering portion into upper and lower sections, and the outlet of the drain passage is covered from below by the partition wall of the gasket.

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