This application is related to and claims priority to Japanese Patent Application No. 2007-063068, filed on Mar. 13, 2007, the entire contents of which is incorporated herein by reference in its entirety.
The present invention relates generally to an internal combustion engine and a vehicle including the internal combustion engine, and more specifically to an internal combustion engine including a pump part and a vehicle including the internal combustion engine.
Conventionally, motorcycles (or other types of vehicles) provided with an engine (internal combustion engine) including a coolant pump (pump part) are known. For example, Japanese Patent Document JP-B-3820970 discloses a lubricant cooling structure for an engine including: an oil pump drive gear (first gear) and a primary drive gear (second gear) that rotate together with a crankshaft; an oil pump idler gear meshed with the oil pump drive gear to rotate as the oil pump drive gear rotates; and a coolant pump gear (pump gear) meshed with the primary drive gear to rotate as the primary drive gear rotates. In this engine, the oil pump idler gear and the coolant pump gear are disposed inside a crankcase so as not to overlap each other as viewed from the extending direction of the crankshaft (from a side).
However, for this engine, because the oil pump idler gear and the coolant pump gear (pump gear) are disposed inside the crankcase so as not to overlap each other as viewed from the extending direction of the crankshaft (from a side), it is necessary to secure a space to be occupied by the oil pump idler gear and the coolant pump gear, which are respectively meshed with the oil pump drive gear (first gear) and the primary drive gear (second gear) which rotate together with the crankshaft inside the crankcase, in the direction perpendicular to the extending direction of the crankshaft. Therefore, the size of the engine (internal combustion engine) is increased in the direction perpendicular to the extending direction of the crankshaft. That is, the size of the internal combustion engine is increased as viewed from an end of the crankshaft.
The present invention, in accordance with one or more embodiments, addresses the foregoing problem, and therefore for an embodiment provides an internal combustion engine that is not increased in size as viewed from an end of the crankshaft and a vehicle including the internal combustion engine.
In accordance with an embodiment, a first aspect of the present invention is directed to an internal combustion engine including: a crankcase; a crankshaft accommodated in the crankcase; a first gear and a second gear disposed inside the crankcase to rotate about the crankshaft; a third gear meshed with the first gear to rotate as the first gear rotates; and a pump part having a pump gear, in which the pump gear is meshed with the second gear to rotate as the second gear rotates; and the third gear and the pump gear are disposed to overlap each other as viewed from an end of the crankshaft.
According to the first aspect in accordance with an embodiment, the third gear and the pump gear are disposed to overlap each other as viewed from an end of the crankshaft as described above. Therefore, it is possible to reduce the space to be occupied by the third gear and the pump gear as viewed from an end of the crankshaft, unlike the case where the third gear and the pump gear are disposed so as not to overlap each other as viewed from an end of the crankshaft. This makes it possible to restrain an increase in the size of the internal combustion engine as viewed from an end of the crankshaft.
In the internal combustion engine according to the first aspect, in accordance with an embodiment, the pump part further includes a water pump unit having a coolant flow-in port and a coolant flow-out port. According to this configuration, coolant can be easily circulated by the coolant flow-in port and the coolant flow-out port.
In the internal combustion engine according to the first aspect, in accordance with an embodiment, the pump part further includes: a first rotary shaft that rotates together with the pump gear; and an impeller attached to the first rotary shaft, with the pump gear disposed between the impeller and the third gear. According to this configuration, the pump gear is disposed to overlap the third gear and the impeller as viewed from an end of the crankshaft, making it possible to restrain an increase in the size of the internal combustion engine as viewed from an end of the crankshaft.
In the internal combustion engine according to the first aspect, in accordance with an embodiment, the pump part further includes: a first rotary shaft that rotates together with the pump gear; and a first restriction member for restraining axial movement of the first rotary shaft. According to this configuration, the first restriction member can easily restrain axial movement of the first rotary shaft even if the first rotary shaft is applied with axial force.
In the internal combustion engine in which the pump part includes the first rotary shaft and the first restriction member, in accordance with an embodiment, the first rotary shaft includes a first outer peripheral groove formed in an outer peripheral surface of the first rotary shaft, with the first restriction member including an engagement part to be engaged with the first outer peripheral groove of the first rotary shaft. According to this configuration, the first restriction member can be easily engaged with the first rotary shaft.
In this case, in accordance with an embodiment, the engagement part of the first restriction member includes: an engagement hole to be engaged with the first outer peripheral groove of the first rotary shaft; and an insertion hole formed to be continuous with the engagement hole and having a hole diameter larger than a diameter of the first rotary shaft. According to this configuration, the first restriction member can be further easily engaged with the first rotary shaft by inserting the first rotary shaft into the insertion hole of the engagement part and having the first outer peripheral groove of the first rotary shaft engaged with the engagement hole which is continuous with the insertion hole.
The internal combustion engine in which the pump part includes the first rotary shaft and the first restriction member, in accordance with an embodiment, further includes: a first bearing member disposed on a side of the crankcase; and a second rotary shaft that rotates together with the third gear, with the first bearing member configured to rotatably support the second rotary shaft of the third gear, and with the pump part further including a second bearing member for rotatably supporting the first rotary shaft of the pump gear. According to this configuration, the first bearing member disposed on a side of the crankcase allows the second rotary shaft to rotate stably, allowing the balancer gear to rotate stably. Also, the second bearing member of the pump part allows the first rotary shaft to rotate stably, allowing the pump gear to rotate stably.
In the internal combustion engine in which the pump part includes the first rotary shaft and the first restriction member, in accordance with an embodiment, the pump part further includes a second restriction member for restraining the pump gear from slipping off from the first rotary shaft, with the first rotary shaft further including a second outer peripheral groove formed in an outer peripheral surface of the first rotary shaft to be engaged with the second restriction member. According to this configuration, the second restriction member and the second outer peripheral groove can easily restrain the pump gear from slipping off from the first rotary shaft.
In the internal combustion engine according to the first aspect, in accordance with an embodiment, the pump gear and the third gear are configured to be positioned higher than an oil surface of oil reserved inside the crankcase. According to this configuration, it is possible to restrain the third gear and the pump gear from contacting the oil reserved in the oil pan, and thus to further restrain a loss of driving force due to such contact.
The internal combustion engine according to the first aspect, in accordance with an embodiment, further includes a crankcase cover provided to cover at least a part of a surface of the crankcase, with the pump part attached to the crankcase cover. According to this configuration, the pump gear included in the pump part can be easily disposed to overlap the third gear disposed inside the crankcase as viewed from an end of the crankshaft.
The internal combustion engine according to the first aspect, in accordance with an embodiment, further includes a second rotary shaft that rotates together with the third gear, with the third gear including a balancer gear, with an extension of the second rotary shaft of the balancer gear disposed within a radius of the pump gear, and with an extension of the first rotary shaft of the pump gear disposed within a radius of the balancer gear. According to this configuration, the balancer gear and the pump gear may be disposed to overlap each other to a greater extent as viewed from an end of the crankshaft, and thus the space to be occupied by the balancer gear and the pump gear may be reduced as viewed from an end of the crankshaft.
In the internal combustion engine according to the first aspect, in accordance with an embodiment, the second gear is formed such that a diameter of the second gear is smaller than that of the first gear. According to this configuration, the rotational speed of the pump gear can be reduced while restraining an increase in the size of the pump gear which is engaged with the second gear.
In accordance with an embodiment, a second aspect of the present invention is directed to a vehicle including the internal combustion engine with any one of the configurations described above. According to this configuration, it is possible to easily obtain a vehicle provided with an internal combustion engine that is not increased in size as viewed from an end of the crankshaft.
The scope of the invention is defined by the claims, which are incorporated into this section by reference. A more complete understanding of embodiments of the present invention will be afforded to those skilled in the art, as well as a realization of additional advantages thereof, by a consideration of the following detailed description of one or more embodiments. Reference will be made to the appended sheets of drawings that will first be described briefly.
The description of various reference numerals and symbols in the drawings may be set forth in accordance with one or more embodiments, for example, as follows: 1: motorcycle, 15: engine (internal combustion engine), 22: crankcase, 31: crankshaft (crankshaft), 32: first crank gear (first gear), 33: second crank gear (second gear), 34: balancer shaft (second rotary shaft), 35: balancer gear (third gear), 43: bearing (first bearing member), 53: crankcase cover, 54: water pump part (pump part), 55: water pump shaft (first rotary shaft), 55b: engagement groove (second outer peripheral groove), 55c: engagement groove (first outer peripheral groove), 56: water pump gear (pump gear), 57: impeller, 59: bearing (second bearing member), 60: plate member (first restriction member), 60a: engagement part, 60b: engagement hole, 60c: insertion hole, 62: circlip (second restriction member), 63a: coolant flow-in port, 63b: coolant flow-out port, and 64: water pump unit.
Embodiments of the present invention and their advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures.
In the motorcycle 1 provided with the engine (internal combustion engine) 15 in accordance with the embodiment of the present invention, as shown in
Handlebars 6 are rotatably attached to the top of the head pipe 2. A pair of front forks 7 having a suspension for absorbing vertical shock is disposed below the handlebars 6. A front wheel 8 is rotatably mounted at the lower end of the front forks 7. A front fender 9 is disposed above the front wheel 8. A radiator 10 is disposed at the rear of the front fork 7.
The front end of a swing arm 11 is attached to the rear end of the main frame 3 via a pivot shaft 3c. A rear wheel 12 is rotatably mounted at the rear end of the swing arm 11. A driven sprocket 13 is attached to the rear wheel 12 so as to rotate together with the rear wheel 12. A drive chain 14 is meshed with the driven sprocket 13. The drive chain 14 is configured to be driven by a drive sprocket 48 of the engine 15 to be discussed later. The engine 15 is mounted as interposed between the upper frame 3a and the lower frame 3b of the main frame 3. The engine 15 is an example of the “internal combustion engine” in accordance with an embodiment of the present invention. A muffler 16 is connected to the engine 15. A fuel tank 17 is disposed on top of the main frame 3. A seat 18 is disposed on top of the seat rail 4.
As shown in
The cylinder head cover 21 is disposed on top of the cylinder head 20. The cylinder head cover 21 is attached to the cylinder head 20 so as to cover a pair of camshafts 29. The camshafts 29 are each provided with a cam 29a for actuating the intake valve 25 and the exhaust valve 26, respectively. As shown in
As shown in
The other end of the connecting rod 24 is rotatably attached to the crankshaft 31. In other words, the crankshaft 31 is configured to rotate as the piston 23 slides relative to the cylinder 19. As shown in
A generation device 40 is attached to the other end of the crankshaft 31 (in the direction of the arrow L). The generation device 40 is configured to generate electricity along with the rotation of the crankshaft 31. A starter gear 41 is fixed to the crankshaft 31 adjacent to the generation device 40 in the direction of the arrow R. The starter gear 41 is connected to a starter motor 42 (see
In accordance with an embodiment, as shown in
The driven gear 37 is meshed with the second crank gear 33. The driven gear 37 is configured to have a larger diameter than that of the second crank gear 33. That is, the driven gear 37 is configured such that the rotational speed of the driven gear 37 is lower than that of the second crank gear 33. The driving force transmitted to the driven gear 37 is transmitted to the main shaft 36 via the clutch mechanism 38. As shown in
As shown in
In accordance with an embodiment, as shown in
In accordance with an embodiment, as shown in
The water pump shaft 55 in accordance with an embodiment is inserted into an insertion hole 53a of the crankcase cover 53. The water pump gear 56 is attached to a side of the water pump shaft 55 in the direction of the arrow L. Specifically, as shown in
In accordance with an embodiment, as shown in
In accordance with an embodiment, as shown in
In accordance with an embodiment, as shown in
As shown in
A cover member 63 is attached at an outer side of the impeller 57 (in the direction of the arrow R) by a screw member 72. A coolant flow-in port 63a is formed in the cover member 63. The water pump part 54 is configured to take coolant cooled by the radiator 10 (see
In accordance with an embodiment, as shown in
In accordance with an embodiment, the diameter of the second crank gear 33 is smaller than that of the first crank gear 32 as described above, and therefore the rotational speed of the water pump gear 56 can be reduced while restraining an increase in the diameter of the water pump gear 56. By restraining an increase in the diameter of the water pump gear 56, it is possible to restrain the lower end of the water pump gear 56 from being positioned in the lower area of the crankcase 22.
In accordance with an embodiment, as shown in
In accordance with an embodiment, the balancer gear 35 and the water pump gear 56 are disposed to overlap each other as viewed from an end of the crankshaft 31 as described above. Therefore, it is possible to reduce the space to be occupied by the balancer gear 35 and the water pump gear 56 as viewed from an end of the crankshaft 31, and thus to restrain an increase in the size of the engine 15 as viewed from an end of the crankshaft 31, unlike the case where the balancer gear 35 and the water pump gear 56 are disposed so as not to overlap each other as viewed from an end of the crankshaft 31.
In accordance with an embodiment, the water pump part 54 is provided with the water pump shaft 55 that rotates together with the water pump gear 56, and the plate member 60 for restraining axial movement of the water pump shaft 55 (in the direction of the arrow L and the arrow R). The plate member 60 can easily restrain axial movement of the water pump shaft 55 (in the direction of the arrow L and the arrow R) even if the water pump shaft 55 is applied with axial force (in the direction of the arrow L and the arrow R).
In accordance with an embodiment, the engagement groove 55c is formed in the outer peripheral surface of the water pump shaft 55, and the plate member 60 is provided with the engagement part 60a for engagement with the engagement groove 55c of the water pump shaft 55. The plate member 60 can be easily engaged with the water pump shaft 55, further restraining axial movement of the water pump shaft 55.
In accordance with an embodiment, the engagement part 60a of the plate member 60 is formed with the engagement hole 60b for engagement with the engagement groove 55c of the water pump shaft 55, and the insertion hole 60c formed to be continuous with the engagement hole 60b and having a hole diameter larger than the diameter of the water pump shaft 55. Therefore, the plate member 60 can be further easily engaged with the water pump shaft 55 by inserting the water pump shaft 55 into the engagement part 60a and having the engagement groove 55c of the water pump shaft 55 engaged with the engagement hole 60b which is continuous with the insertion hole 60c.
In accordance with an embodiment, the water pump part 54 is provided with the circlip 62 for restraining the water pump gear 56 from slipping off from the water pump shaft 55, and the engagement groove 55b for engagement with the circlip 62 is formed in the outer peripheral surface of the water pump shaft 55 in the vicinity of one end thereof (in the direction of the arrow L). The circlip 62 and the engagement groove 55b can easily restrain the water pump gear from slipping off from the water pump shaft 55.
In accordance with an embodiment, an extension of the balancer shaft 34 of the balancer gear 35 is disposed within the radius of the water pump gear 56, and an extension of the water pump shaft 55 of the water pump gear 56 is disposed within the radius of the balancer gear 35. Therefore, the balancer gear 35 and the water pump gear 56 can be disposed to overlap each other to a greater extent as viewed from an end of the crankshaft 31, and thus the space to be occupied by the balancer gear 35 and the water pump gear 56 can be reduced as viewed from an end of the crankshaft 31.
It should be understood that the embodiments disclosed herein are construed to be illustrative in all respects rather than restrictive. The scope of the present invention is defined by the scope of the claims rather than by the description of the above embodiments, and includes all modifications falling within the scope of the claims and equivalents thereof.
For example, in an above embodiment, a motorcycle is described as an example of the vehicle including an internal combustion engine. However, the present invention is not limited thereto, and may be applied to vehicles provided with an internal combustion engine other than motorcycles, such as bicycles, tricycles, and ATVs (all terrain vehicles).
In an above embodiment, the balancer gear is disposed to overlap the water pump gear as viewed from an end of the crankshaft. However, the present invention is not limited thereto, and any gear other than the balancer gear may be disposed in an overlapping manner.
In an above embodiment, an extension of the balancer shaft is disposed within the radius of the water pump gear, and an extension of the water pump shaft is disposed within the radius of the balancer gear. However, the present invention is not limited thereto, and an extension of the balancer shaft may not be disposed within the radius of the water pump gear, or an extension of the water pump shaft may not be disposed within the radius of the balancer gear.
In an above embodiment, the circlip (C-ring) is provided to restrain the water pump gear from slipping off from the water pump shaft. However, the present invention is not limited thereto, and any member other than the circlip such as a nut may be used to restrain the water pump gear from slipping off from the water pump shaft.
Embodiments described above illustrate but do not limit the invention. It should also be understood that numerous modifications and variations are possible in accordance with the principles of the present invention. Accordingly, the scope of the invention is defined only by the following claims.
Number | Date | Country | Kind |
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2007-063068 | Mar 2007 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
5564518 | Ishii et al. | Oct 1996 | A |
6170597 | Fukuda | Jan 2001 | B1 |
6601474 | Ishimaru et al. | Aug 2003 | B2 |
7475617 | Gleasman et al. | Jan 2009 | B2 |
Number | Date | Country |
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2003-161133 | Jun 2003 | JP |
Number | Date | Country | |
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20080227578 A1 | Sep 2008 | US |