Title of Invention

STARTER OF INTERNAL COMBUSTION ENGINE FOR MOTORCYCLE

Abstract

[Problem] To shorten a size of a crank shaft and make a starter and an internal combustion engine compact in size in a starter of the internal combustion engine for a motorcycle comprising a rear wheel shaft fixed to a side of the rear wheel and a crank shaft in parallel with the rear wheel shaft. [Solving Means] This starter is constituted by an ACG rotor integrally arranged with said crank shaft at one end of the crank shaft in opposition to said rear wheel, a cooling fan arranged at an outside part of said ACG rotor, a scroll cover for sending cooling air generated at said cooling fan to a high temperature part such as an outer circumference part of a cylinder block, a starter motor rotated at a rotating shaft in parallel with said crank shaft, provided with a gear protruded toward the rotating shaft and fixed to a crank case, and a driven gear arranged at an outer circumferential surface of said ACG rotor and engaged with a protruding gear of said starter motor, the gear protruding part of said starter motor is arranged near the terminal end in said scroll cover. [Selected Drawing]

Full Text

[Document's Name] Specification [Title of the Invention] Starter of Internal Combustion Engine for Motorcycle [Technical Field] [0001] The present invention relates to a starter of an internal combustion engine for a motorcycle and more particularly to a starter of an internal combustion engine comprising a forced air-cooling fan and a scroll cover becoming an air passage. [Background Art] [0002] The prior art starter of an internal combustion engine for a motorcycle is constituted in general by a starter motor, a solenoid, a starter driving gear arranged at the starter motor shaft, a starter driven gear arranged at the crank shaft and a series of gears installed between the aforesaid driving gear and the starter driven gear (refer to patent document 1 and patent document 2, for example) [3] In addition, the starter driven gear is arranged at one end of the crank shaft as described above and ACG (Alternating Current Generator) or a forced air cooling fan or an air flow passage cover was arranged at the other end of the crank shaft (refer to patent document 2, for example), so that no relation of utilization could be confirmed among the starter, ACG and the air flow passage. [4] [Patent document 1] Gazette of Patent Laid-open No. 25570/2000 (Fig. 1) [5] [Patent document 2] Gazette of Utility Model Laid-open No. 42431/1995 (Fig. 4) [Disclosure of the Invention] [Problem to be Solved by the Invention] [6] In the prior art starter, the starter driven gear was directly arranged at the crank shaft, a length of the crank shaft was apt to be extended. In addition, the starter motor and the crank shaft were spaced apart at a certain installing location of the starter motor and further when a diameter of the starter driven gear was small, it was necessary to arrange a series of gears for deceleration between the starter driving gear and the starter driven gear. [7] It is an object of the present invention to reduce a crank shaft size and sizes of the starter and the internal combustion engine by arranging the starter using an outer circumference part and an inside space of the air flow path cover. [Problem to be Solved by the Invention] [8] The present invention has solved the aforesaid problem and the present invention described in claim 1 relates to a starter of an internal combustion engine for a motorcycle comprising a rear wheel shaft fixed to a side part of a rear wheel and a crank shaft in parallel with said rear wheel shaft so as to rotationally drive the rear wheel characterized in that the same is constituted by an ACG rotor integrally arranged with said crank shaft at one end of the crank shaft in opposition to said rear wheel, a cooling fan arranged at an outside part of said ACG rotor, a scroll cover for sending cooling air generated at said cooling fan to a high temperature part such as an outer circumference part of a cylinder block, a starter motor rotated at a rotating shaft in parallel with said crank shaft, provided with a gear protruded toward the rotating shaft and fixed to a crank case, and a driven gear arranged at an outer circumferential surface of said ACG rotor and engaged with a protruding gear of said starter motor, the gear protruding part of said starter motor is arranged near the terminal end in said scroll cover. [Effect of the Invention] [9] The present invention enables a crank shaft size to be reduced and a compact size of the starter and the internal combustion engine to be attained. [Best Mode for Carrying Out the Invention] [10] Fig. 1 is a development view in section including each of the rotating shafts of the four-stroke cycle type internal combustion engine for a motorcycle in accordance with one preferred embodiment of the present invention, and its section is seen from above under a state in which the internal combustion engine is installed on a motorcycle. In this figure, an outer shell of this internal combustion engine is constituted by a left crank case 1, a right crank case 2, a left crank case cover A 3, a right crank case cover 4, a cylinder block 5, a cylinder head 6 and a cylinder head cover 7 . The crank shaft 8 is comprised of right and left portions, and they are integrally assembled with a crank pin 9. The crank shaft 8 is rotatably supported by each of the left crank case 1 and the right crank case 2 through each of the main bearings 10, 11. A piston 13 is connected to the crank pin 9 through the connecting rod 12. The piston 13 reciprocates within the cylinder block 5 in an axial direction of the cylinder. A combustion chamber 14 is formed at the lower surface of the cylinder head 6. A spark plug 15 is installed at the cylinder head 6 and its extremity end is present near the aforesaid combustion chamber 14 . A cam shaft 16 of a moving valve mechanism is rotatably supported in the cylinder head 6. [0011] A cam chain chamber 17 extending from a left end space of the cam shaft 16 to the left end space of the crank shaft 8 is arranged at the left side of the internal combustion engine assembled as described above. A driving sprocket 18 is fitted to the left side portion of the crank shaft 8, a driven sprocket 19 is fixed to the left end of the cam shaft 16, and a cam chain 20 is applied over both sprockets. With this arrangement above, a rotational driving force of the crank shaft 8 is transmitted to the cam shaft 16 and then an intake valve or an exhaust valve arranged at the cylinder head 6 can be driven by a cam formed at the cam shaft 16 under a predetermined timing. A main shaft 21 and a counter-shaft 22 of a transmission are arranged below the crank shaft. The main shaft 21 is rotatably supported at each of the left crank case 1 and the right crank case 2 through bearings. A primary deceleration driving gear 23 is fixed to the left end of the crank shaft 8, and a primary deceleration driven gear 24 engaged with the driving gear 23 is rotatably arranged at the left end of the main shaft 21. The primary deceleration driven gear 24 is connected to a clutch outer 26 of a clutch 25. A clutch inner 27 of the clutch 25 is fixed to the main shaft 21. The counter shaft 22 is an output shaft of the internal combustion engine and a wheel 28 is directly fixed to the left end of the counter shaft 22. [0013] Four driving gears Ml to M4 are arranged at the main shaft 21 in an order of a diameter size and each of them is fixed to the main shaft. Four driven gears CI to C4 always engaged with the four gears Ml to M4 of the aforesaid main shaft are installed at the counter shaft 22 in such a way that they can freely rotate in respect to the counter shaft 22. A large diameter part 22a of the counter shaft 22 having the driven gears CI to C4 installed therein is formed with a central hole 3 0 having one end released at the center part, and four axial slits 32 communicating the central hole 30 with the outer circumference of the thick-walled cylinder part 31 are equally spaced apart and cut in a circumferential direction at the thick-walled cylindrical part 31 around it. A slit of cross-shaped section is formed by the aforesaid central hole 30 and the four slits 32. A pawl connecting shaft 33 and a cross-shaped pawl (a gear rotation engagement claw) 34 fixed to the extremity end of the pawl connecting shaft are installed at the central hole and the slit of cross-shaped section of the aforesaid counter shaft 22 in such a way that they can be axialy slid. Inner circumferential portions of the driven gears CI to C4 are formed with axial engagement parts 35 engaged with the aforesaid cross-shaped pawl 34. When a driver moves the pawl connecting shaft 33 by an operating device not shown and selects any one of the driven gears CI to C4, each of the extremity ends of the cross-shaped pawl 34 fixed to the extremity end of the pawl connecting shaft 33 is engaged with the selected engagement portion 3 5 of the driven gear so as to stop the free rotation of the gear against the counter shaft. With this operation, a speed change corresponding to a gear ratio between the driven gear fixed to the counter shaft 22 and the driving gear placed at the main shaft 21 engaged with the former gear is carried out, rotation of the crank shaft 8 is transmitted to the counter shaft 22 through the main shaft 21 and the wheel 28 is driven. The right end of the crank shaft 8 is provided with the ACG (Alternating Current Generator) 40. ACG 40 is constituted by an ACG stator 41 fixed to the right crank case 2 and an ACG rotor 42 fixed to the crank shaft 8 and rotated at the outer circumference of the ACG stator as the crank shaft 8 is rotated. A centrifugal fan 43 is fixed to the right side surface of the aforesaid ACG rotor 42 and the central fan 43 is rotated together with the ACG rotor 42. Air flow flowed through many air intake holes 44 arranged at the right crank case cover 4 and swirled by the centrifugal fan 43 flows through the inner side of the right crank case cover 4, is transmitted to the outer circumferences of the cylinder block 5 or the cylinder head 16 to cool them. A starter driven gear 53 to be engaged with the pinion of a shift type starter described later is integrally arranged on an outer circumference of the ACG rotor 42. [0016] Fig. 2 is a view for showing a longitudinal section of a part of the internal combustion engine from the right side. The internal combustion engine shown in Fig. 2 is illustrated under an attitude in which it is installed on the vehicle. An arrow F indicates a front side and an arrow U indicates an upper side. In this figure, there are seen at the right half part a cylinder block 5, a piston 13, a cylinder head 6, an intake port 45, an exhaust port 46, an intake valve 47 and an exhaust valve 48. At the left half part of the figure are seen a left crank case 1, a crank shaft 8 and a crank pin 9. A scroll cover 54 integrally communicated with the right crank case cover 4 is arranged at the outer circumference of the crank chamber. This is an air passage having its sectional area gradually enlarged while it turns from the lower part of the figure to the left side and reaches to the upper part and this is also an air flow passage generated by the centrifugal fan 43. A cylindrical cover 55 integrally communicated with the right crank case cover 4 and the scroll cover 54 is arranged at the outer circumferences of the cylinder block 5 and the cylinder head 6. Since the terminal end of the scroll cover 54 and the starting end of the cylindrical cover 55 are smoothly connected to each other, it is vague which location is an interface part and a part corresponding to the interface between the crank case 1 and the cylinder block 5 is assumed to be an interface part. The air flow passed through the scroll cover 54 enters into the cylindrical cover 55 to cool the cylinder block 5 or the cylinder head 6. The air flow flows out of an air outlet not shown. [17] There is provided a starter motor 50 having a rotating shaft in parallel with the crank shaft 8 near the terminal end of the scroll cover 54. There is provided a solenoid 51 having a center line in parallel with the rotating shaft of the starter motor 50 adjacent to the starter motor 50. The rotating shaft of the starter motor 50 is installed with a pinion 52. This pinion is a small diameter gear that can be engaged with the starter driven gear 53 fixed to the outer circumference of the ACG rotor 42, and also this is a starter driving gear. In this figure, only a pitch circle of each of the pinion 52 and the starter driven gear 53 is illustrated. [18] Fig. 3 is a sectional view taken along line III-III of Fig. 2. The starter motor 50 and a solenoid 51 are arranged above the crank cases 1, 2. A rotating shaft 50a of the starter motor 50 and the center line 51a of the solenoid 51 are in parallel with the center line of the crank shaft 8. The AC rotor 42 is fixed to the crank shaft 8 and rotated together with the crank shaft 8. A starter driven gear 53 is fixed to the outer circumference of the ACG rotor 42. [19] A pinion 52 is installed at the rotating shaft 50a of the starter motor 50 through a pinion holding device 56. The pinion holding device 56 is a device for rotating the pinion 52 through rotation of the starter motor 50 and holding the pinion 52 in such a way that it can move toward the rotating shaft 50a. When the starter switch is turned on by the pinion protruding mechanism not shown, it is protruded in an axial direction, it is engaged with the starter driven gear 53 and when the starter switch is turned off, it returns to the original position and the aforesaid engagement is released. [20] The pinion protrusion mechanism comprises the aforesaid pinion holding device 56, a shift lever not shown and installed between the solenoid 51 and the starter motor 50 and a return spring installed at the shift lever. One end of the shift lever is placed at such a position as one where it can be absorbed by the solenoid 51 and the other end of the shift lever is present at a location where it is engaged with the pinion holding device 56. The pinion 52, a part of the pinion holding device 56 and the pinion protrusion cover 57 covering these portions are arranged in the flow passage near the terminal end of the scroll cover 54. [0021] A starting position of the internal combustion engine for a motorcycle in the preferred embodiment of the present invention is constituted by arranging the starter motor 50, solenoid 51, pinion 52, starter driven gear 53, pinion holding device 56, pinion protrusion mechanism, and electronic component parts such as battery and starter switch or the like [0022] When the starter switch is turned on in this starter, the solenoid is electrically energized to generate a suction force, the plunger is moved, the pinion 52 is pushed out through the shift lever and the pinion holding device 56 and it is engaged with the starter driven gear 53. A main contact point is closed by motion of the plunger, a current flows from the battery to the starter motor, a torque of the starter motor 50 is transmitted to the starter driven gear 53 through the pinion 52, the crank shaft 8 starts to rotate through the ACG rotor 42 and then the internal combustion engine starts to operate. After starting the engine, if the starter switch is turned off, an attracting force acting on the plunger diminishes, the pinion is removed from the starter driven gear 53 with a recovering force of the returning spring installed at the shift lever and returns to the original position. Further, in the shift type starter of the present invention, the engaged state between the pinion and the starter driven gear 53 is not released as long as the starter switch is not turned off even after the internal combustion engine starts to operate, so that there is provided one-way clutch (not shown) for preventing damage or burn-loss. [0023] As described above in detail, the starting device of the preferred embodiment of the present invention has no direct arrangement of the starter driven gear with the crank shaft, but it is mounted using the outer circumference of the ACG rotor, so that it is possible to shorten a size of the crank shaft. In addition, a sufficient large diameter of the starter driven gear can be realized with the aforesaid structure, so that it is not necessary to arrange another gear for speed reduction between the pinion of the starter and the starter driven gear, resulting in that a small-sized starter can be attained. Since a part of the starter is mounted in the scroll cover, a small-sized formation of the internal combustion engine can further be realized. [Brief Description of the Drawings] [24] [Fig. 1] This is a development view in section including each of the rotating shafts in a four-stroke cycle type internal combustion engine for a motorcycle in accordance with one preferred embodiment of the present invention. [Fig. 2] This is a view seen from the right side of a longitudinal section of a part of the internal combustion engine. [Fig. 3] This is a sectional view taken along line III-III of Fig. 2. [Description of Reference Numerals] [25] Ml, M2, M3 and M4 : transmission driving gear fixed to the main shaft CI, C2, C3, C4: transmission driven gear freely fitted to a counter shaft 1: left crank case 2: right crank case 3: left crank case cover 4: right crank case cover 5: cylinder block 6: cylinder head 7: cylinder head cover 8: crankshaft 9: crank pin 10 : main bearing 11: main bearing 12: connecting rod 13: piston 14: combustion chamber 15: sparkplug 16: camshaft 17: cam chain chamber 18: driving sprocket 19: driven sprocket 20: cam chain 21: main shaft 22: counter shaft 22a: large diameter part of the counter shaft 23: primary deceleration driving gear 24: primary deceleration driven gear 25: clutch 26: clutch outer 27: clutch inner 28: wheel 30: central hole 31: thick wall cylinder part 32: axial slit 33: pawl connecting shaft 34: cross-shaped pole 35: engagement part 40: ACG (Alternating Current Generator) 41: ACG stator 42: ACG rotor 43: centrifugal fan 44: air intake hole 45: intake port 46: exhaust port 47: intake valve 48: exhaust valve 50: starter motor 51: solenoid 52: pinion 53: starter driven gear 54: scroll cover 55: cylindrical cover 56: pinion holding device 57 : cover at pinion protruded part We claim: 1. A starter of an internal combustion engine for a motorcycle comprising a rear wheel shaft fixed to a side part of a rear wheel and a crank shaft in parallel with said rear wheel shaft so as to rotationally drive the rear wheel, characterized in that: the same is constituted by an ACG rotor integrally arranged with said crank shaft at one end of the crank shaft in opposition to said rear wheel, a cooling fan arranged at an outside part of said ACG rotor, a scroll cover for sending cooling air generated at said cooling fan to a high temperature part such as an outer circumference part of a cylinder block, a starter motor rotated at a rotating shaft in parallel with said crank shaft, provided with a gear protruded toward the rotating shaft and fixed to a crank case, and a driven gear arranged at an outer circumferential surface of said ACG rotor and engaged with a protruding gear of said starter motor, the gear protruding part of said starter motor is arranged near the terminal end in said scroll cover.

Documents:

180-CHE-2005 AMENDED PAGES OF SPECIFICATION 08-12-2011.pdf

180-CHE-2005 AMENDED CLAIMS 08-12-2011.pdf

180-CHE-2005 EXAMINATION REPORT REPLY RECEIVED 08-12-2011.pdf

180-CHE-2005 FORM-3 08-12-2011.pdf

180-CHE-2005 POWER OF ATTORNEY 08-12-2011.pdf

180-CHE-2005 CORRESPONDENCE PO.pdf

180-CHE-2005 ABSTRACT.pdf

180-CHE-2005 CLAIMS.pdf

180-CHE-2005 CORRESPONDENCE OTHERS.pdf

180-CHE-2005 DESCRIPTION (COMPLETE).pdf

180-CHE-2005 DRAWINGS.pdf

180-CHE-2005 FORM 1.pdf

180-CHE-2005 FORM 18.pdf

180-CHE-2005 FORM 3.pdf

180-CHE-2005 FORM 5.pdf