Title of Invention

"COOLING DEVICE FOR A VEHICULAR POWER UNIT"

Abstract

[Object] To provide a vehicular power unit composed of a power portion and a power transmitting portion, wherein the heat generated on the power portion is effectively escaped, thus improving the cooling efficiency. [Construction] In a vehicular power unit including a power portion 2 containing a power generating means, and a power transmitting portion 3 for transmitting a power of the power generating means, the power portion 2 being mounted on the power transmitting portion 3, a space 62 is formed between the power portion 2 and the power transmitting portion 3 and a wind exhaust port 63 is provided for escaping a cooling wind passing through the space 62. [Selective Drawing]

Full Text

The present invention relates to a cooling device for a vehicular power unit. In some small sized vehicles such as a motor-bicycle and a cycle car, a power portion such as an engine and motor is connected to a power transmitting portion such as a transmission, and they are mounted on a vehicular body as a power unit. In such a power unit, a vibration absorbing member is provided between the power portion and the power transmitting portion for preventing the noise and vibration generated on the power portion side from being transmitted to the power transmitting portion (for example, unexamined Japanese Utility Model Publication No. SHO62-24030). The above-described prior art power unit, however, has an inconvenience that, since the vibration absorbing member is provided between the power portion and the power transmitting portion, the heat generated on the power portion side is difficult to be escaped, leading to the reduction in the cooling efficiency. According to the present invention, there is provided a cooling device for a vehicular power unit including a power portion for containing a power generating means and a power transmitting portion for transmitting a power of said power generating means, said power portion being mounted to said power transmitting portion, wherein a space is formed between said power portion and said power transmitting portion, and a wind exhaust port is provided for escaping a cooling wind passing through said space; characterized in that said transmitting portion is combined with the power portion by a bolt; a drive pulley and a drive pulley is connected by the transmission portion of inside transmitting case and a belt is hung between the driven pulley and the drive pulley thereby preventing heat conduction to the belt inside the power portion and improving durability. Since a space is formed between the power portion and the power transmitting portion a cooling wind is made to pass through the space, which is effective to certainly escape the heat on the power portion side, resulting in the improved cooling efficiency. Moreover, since a wind exhaust port is provided, the cooling wind is made to be easily flow, thus improving the cooling efficiency. Hereinafter, one preferred embodiment of the present invention will be described with reference to the accompanying drawings. [Fig. 1] A side view of a motor-bicycle.[Fig. 2] A left side view, partly in cross-section, of a power unit. [Fig. 3] A sectional view taken along line 3-3 of Fig. 2. [Fig. 4] A view, similar To Fiy. 2, showing another embodiment. [Explanation of Symbols] 2: power portion, 3: power transmitting portion, 62: space, 63: wind exhaust port. Fig. 1 shows a small-sized motor-bicycle (scooter type) mounted with a vehicular power unit of the present invention. In the figure, reference numeral 1 designates a power unit; 2 is an engine as a power portion; 3 is a power transmitting portion; 4 is an exhaust pipe extending from the engine; and 5 is a muffler mounted on the rear'portion of the exhaust pipe. [0007] Fly. 2 is a loft side view, partly in cross-section, of the power unit; and Fig. 3 is a sectional view taken along line 3-3 of Fig. 2. The engine 2 includes a cylinder 10, a crank case 11 and the like. The crank case 11 is formed of right and left halves lla and l1b joined to each other. The cylinder 10 is mounted on the crank case 11. A cylinder head 13 is mounted on the upper portion of the cylinder 10, and an ignition plug 14 is provided on the cylinder head 13. A piston 16 is slidably disposed in the cylinder 10, and it is connected to a crank shaft 17 by means of a connecting rod 18. [0008] The engine 2 is supported by a transmitting case 20 of a power transmitting portion 3. The transmitting case 20 is formed of a left case 21 and a right case 22. The left case is formed of a first case 23 and a second case 24. The first •'-' *': case 23 is formed of a front case 23a and a rear case 23b. [0009] As shown in Fig. 2, a plurality of insertion holes 25 — are formed in the crank case 11 to be spaced at equal intervals. As shown in Fig. 3, insertion holes 21b and 22b corresponding to the insertion holes 25 are respectively formed in a wall portion 2la of the left case 21 and a wall portion 22a of the right case 22. Bolts Bl are made to pass through these insertion holes 25, 21b and 22b. Both the ends of the bolts Bl are supported by the wall portions 2la and 22a by way of rubber bushes 27 as vibration absorbing members and collars 28. The engine 2 is thus supported in a floating manner on the transmitting case 20 side. In this embodiment, the engine 2 is supported in a floating manner at three points (a), (b) and (c) in Fig. 2. However, since the insertion holes 25 are provided at the three points or more, the angle of the engine 2 relative to the transmitting case 20 can be changed by removing the bolts t i Bl, Bl and Bl, rotating the engine 2 forward or rearward, and fastening the engine 2 by the bolts Bl, Bl and Bl again. [0010] As shown in Fig. 3, an ACG 32 is disposed near the end portion of the crank shaft 17, and fans 35... are provided outside the ACG 32. Case pieces 50 and 51 are integrally formed on the left case 21 and the right case 22, respectively. A case 53 is connected to the case pieces 50 and 51. An outer case 54 is connected to the outside of the case 53. An elastic member 55 is disposed between the case 53 and the outer case 54. [0011] A transmitting mechanism 35 of this embodiment, which is provided within the transmitting case 20, will be described below. A crank shaft 17 projects within .the, transmitting case 20. A drive pulley 37 is provided at the portion, facing to the interior of the case 20, of the crank shaft 17. The drive pulley 37 includes a dish-like fixed face 37a fitted to the end of the crank shaft 17, and a dish-like movable face 37b provided on the crank shaft 17 so as to face to the fixed face 37a and to be slidable in the axial direction. [0012] On the other hand, an input shaft 40, an intermediate shaft 41 and an axle 42 are rotatably .disposed in the rear portion of the transmitting case 20. A driven pulley 43 is provided on the input shaft 40. The driven pulley 43 is formed of a dish-like fixed face 43a fixed on the input shaft 40, and a movable face 43b rotatably provided on the input shaft 40 so as to be slidable along the input shaft 40. A V belt 44 is hung between the driven pulley 43 and the drive pulley 37. [0013] A gear 45 is provided on the end portion of the input shaft 40, and it is screwed with a gear 46 provided on an intermediate shaft 41. A gear 47 provided on the intermediate shaft 41 is screwed with a gear 48 provided on the axle 42. The rotation of the crank shaft 17 is thus transmitted from the drive pulley 37 to the input shaft 40 by way of the V belt 44. The rotation is then transmitted to the intermediate . '• shaft 41 by way of the gears 45 and 46, and is further transmitted to the axle 42 by way of the gears 47 and 48, thus rotating a rear wheel W. [0014] As shown in Fig. 2, a mounting portion 49 is formed on the lower surface of the transmitting case 22. The rear end side of a rocking link 50 whose front end is pivotably supported by a vehicular frame is pivotably supported by the mounting portion 49, as shown in Fig. 1.A bracket 60 is, as shown in Fig. 2, mounted on the front portion of a muffler 5, and a flange 61 is provided on the right case 22 of the transmitting case 20. The flange 61 and the bracket 5 are fastened with each other by means of a bolt B7. The muffler 5 is thus supported by the transmitting case 20. [0015] In this embodiment, as shown in Figs. 2 and 3, a space 62 is formed between the crank case 11 and the transmitting case 20, and a wind exhaust port 63 is formed between the left case 21 and the right case 22. As the fans 35 are rotated, a cooling -wind is made to flow in the direction of the arrow in Figs. 2 and 3. The cooling wind passes through the space 62 between the crank case 11 and the transmitting case 20, and is exhausted to the outside, as shown by the arrow, through the wind exhaust port 63. In this way, the crank case 11 is cooled by the cooling wind passing through the space 62, and accordingly, the heat generated within the crank case 11 can be positively escaped, resulting in the improved cooling efficiency. In this embodiment, the wind exhaust port 63 is further provided, so that the cooling wind is made to positively flow, thus further improving the cooling efficiency. Additionally, even when water, sands and the like permeate in the space 62 between the crank case 11 and the transmitting case 20, they can be exhausted to the outside through the wind exhaust port [0016] The power generating means of the present invention may be a motor, and a cooling wind is not one generated by the engine cooling fan but may be running wind. Fig. 4 shows another embodiment. In this embodiment, an oil pump 70 is provided in the front portion of the transmitting case 20. The oil pump 70 is connected to the crank case 17 by means of the connecting shaft 71, and the gear 72 formed at the front end of the transmitting case 20 is meshed with the crank case 17. The connecting shaft 71 is inserted in an opening 73 formed at the front end of the transmitting case 20. According to the structure of this embodiment, a cooling wind can be escaped from the opening 73 to-the outside. [0018] [Effect of the Invention] As described above, according to the present invention, since a space is formed between a power portion and a power transmitting portion, a cooling wind is made to flow through the space, which certainly escapes the heat on the power portion side, thus improving the cooling efficiency. Moreover, since a wind exhaust port is provided, the cooling wind is made to easily flow, thus further improving the cooling efficiency. Additionally, since the wind exhaust port is provided, even when sands and the like permeate in the space, they can be discharged to the outside through the wind exhaust port. WE CLAIM:- 1. A cooling device for a vehicular power unit including a power portion for containing a power generating means and a power transmitting portion for transmitting a power of said power generating means, said power portion being mounted to said power transmitting portion, wherein a space is formed between said power portion and said power transmitting portion, and a wind exhaust port is provided for escaping a cooling wind passing through said space; characterized in that said transmitting portion is combined with the power portion by a bolt; a drive pulley and a driven pulley is connected by the transmission portion of inside transmitting case and a belt is hung between the driven pulley and the drive pulley thereby preventing heat conduction to the belt inside the power portion and improving durability. 2. A cooling device for a vehicular power unit as claimed in claim 1 wherein said power generating means is constituted of an air cooling engine, and said cooling wind is generated by a cooling fan of said engine. 3. A cooling device for a vehicular power unit substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Documents:

1483-del-1994-abstract.pdf

1483-del-1994-claims.pdf

1483-del-1994-correspondence-others.pdf

1483-del-1994-correspondence-po.pdf

1483-del-1994-description (complete).pdf

1483-del-1994-drawings.pdf

1483-del-1994-form-1.pdf

1483-del-1994-form-13.pdf

1483-del-1994-form-2.pdf

1483-del-1994-form-4.pdf

1483-del-1994-form-9.pdf

1483-del-1994-gpa.pdf

1483-del-1994-petition-others.pdf

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