Title of Invention

RADIATOR COVER STRUCTURE OF SMALL-SIZED VEHICLE

Abstract To provide a radiator cover structure of a small-sized vehicle which can miniaturize the radiator cover structure while maintaining the reduction of weight as much as possible can ensure a sufficient tank capacity and, at the same time, can simplify surface finishing of an aesthetic appearance of the radiator cover structure. [Means for Resolution] In a radiator cover structure of a small-sized vehicle in which a radiator 110 is constituted of a heat-radiation-use radiator core portion 111 and a pair of synthetic-resin-made radiator tank portions 112, 113 which is connected to the radiator core portion 111 and performs supplying and discharging of cooling water, a synthetic-resin-made first radiator cover 120 in which a cooling wind passage is formed in a state that the cooling wind passage faces the radiator core portion 111 in an opposed manner covers the radiator 110, and a metal-made second radiator cover 130 covers the radiator tank portion 112 in cooperation with the first radiator cover 120.
Full Text [Designation of Document] specification
[Title of the Invention] RADIATOR COVER STRUCTURE OF
SMALL-SIZED VEHICLE
[Technical Field]
[0001]
The present invention relates to a radiator device of a small-sized vehicle such as a motorcycle and a three-wheeled vehicle, and more particularly to a cover structure of a radiator which is mounted on a side surface of a vehicle body. [Background Art] [0002]
With respect to a radiator device which is mounted on a side surface of a vehicle body, there has been known an example which is described in the patent application (patent document 1) filed by the same applicant of this application prior to this application.
[patent document 1] JP-A-2002-129960 [0003]
In the patent document 1, a radiator device is mounted on a right side surface of an internal combustion engine which is arranged in front of a swing-type power unit which is mounted on a motorcycle.
An AC generator is mounted on a right end of a crankshaft of the internal combustion engine which is directed in the laterally horizontal direction, and a radiator is arranged

close to a radiator fan which is integrally formed on a rotor
of the AC generator.
[0004]
The radiator is covered with a radiator cover from the outside.
The radiator cover forms a louver for introducing air from the outside on an outside surface thereof, and a peripheral wall which covers a periphery of the radiator having a rectangular shape covers upper and lower radiator tanks.
The radiator cover is made of a synthetic resin and hence, the reduction of weight of the radiator cover is realized. [Disclosure of the Invention] [Problems that the Invention is to solve] [0005]
To realize the above-mentioned reduction of weight of a radiator body, an attempt has been made to form a radiator tank portion except for a radiator core portion which constitutes a heat radiation area using a synthetic resin. However, a thickness of the tank portion is increased to ensure strength of the radiator tank portion and hence, it becomes difficult to ensure a capacity in the inside of the tank. [0006]
The invention has been made under such circumstances and it is an object of the invention to provide a radiator cover structure of a small-sized vehicle which can miniaturize the

radiator cover structure while maintaining the reduction of weight as much as possible and can ensure a sufficient tank capacity and, at the same time, can simplify surface finishing of an aesthetic appearance of the radiator cover structure. [Means for Solving the Problem] [0007]
To achieve the above-mentioned object, the invention according to claim 1 is directed to a radiator cover structure of a small-sized vehicle in which a radiator is constituted of a heat-radiation-use radiator core portion and a pair of synthetic-resin-made radiator tank portions which is connected to the radiator core portion and performs supplying and discharging of cooling water, wherein a synthetic-resin-made first radiator cover in which a cooling wind passage is formed in a state that the cooling wind passage faces the radiator core portion in an opposed manner covers the radiator, and a metal-made second radiator cover covers the radiator tank portion in cooperation with the first radiator cover. [0008]
The invention described in claim 2 is, in the radiator cover structure of the small-sized vehicle described in claim 1, characterized in that the first radiator cover covers the second radiator cover. [0009]

The invention described in claim 3 is, in the radiator cover structure of the small-sized vehicle described in claim
2, characterized in that the second radiator cover covers the radiator tank portion and, at the same time, the second radiator cover is fastened to the radiator together with the radiator tank portion.
[0010]
The invention described in claim 4 is, in the radiator cover structure of the small-sized vehicle described in claim
3, characterized in that the radiator arranges the radiator tank portions at upper and lower portions thereof, the second radiator cover covers only the upper radiator tank portion, and an exhaust pipe is arranged below the lower radiator tank portion.
[0011]
The invention described in claim 5 is, in the radiator cover structure of the small-sized vehicle described in claim 3, characterized in that the second radiator cover is constituted by integrally joining a cover body portion which is formed of an outer wall and a peripheral wall having the substantially same profile as the radiator tank portion and a strip-like stay portion which forms mounting holes in both end portions thereof to each other. [Advantage of the Invention] [0012]

According to the radiator cover structure of the small-sized vehicle described in claim 1, in the radiator which has the radiator tank portion made of the synthetic resin thus realizing the reduction of weight, the synthetic-resin-made first radiator cover and the metal-made second radiator cover cover the radiator tank portion in a cooperative manner and hence, while allowing the radiator cover to ensure a sufficient strength, a thickness of the synthetic-resin-made radiator tank portion can be decreased thus ensuring the tank portion capacity.
Further, since the first radiator cover which covers the radiator is made of the synthetic resin, it is possible to simplify surface finishing of an aesthetic appearance of the second radiator cover. [0013]
According to the radiator cover structure of the small-sized vehicle described in claim 2, since the synthetic-resin-made first radiator cover covers the metal-made second radiator cover, it is possible to further simplify the surface finishing of the aesthetic appearance of the second radiator cover thus realizing the reduction of cost. [0014]
According to the radiator cover structure of the small-sized vehicle described in claim 3, since the metal-made second radiator cover covers the radiator tank portion and,

at the same time, the second radiator cover is fastened to the radiator together with the radiator tank portion, it is possible to decrease man-hours for assembling. [0015]
According to the radiator cover structure of the small-sized vehicle described in claim 4, since the metal-made second radiator cover covers only the upper radiator tank portion, the reduction of weight can be maintained as much as possible and, at the same time, since the upper radiator tank portion is covered with the metal-made second radiator cover and the first radiator cover in a duplicate manner and the exhaust pipe is arranged below the lower radiator tank portion and hence, it is possible to effectively protect the radiator. [0016]
According to the radiator cover structure of the small-sized vehicle described in claim 5, the second radiator cover is-constituted by integrally joining the cover body portion which is formed of the outer wall and the peripheral wall having the substantially same profile as the radiator tank portion and the strip-like stay portion which forms mounting holes in both end portions thereof to each other and hence, the cover body portion can be easily formed by drawing thus enhancing the accuracy of dimensions of the mounting hole formed in the stay portion. [Best Mode for Carrying out the Invention]

[0017]
Hereinafter, an embodiment according to the invention is explained in conjunction with Fig. 1 to Fig. 10.
Fig. 1 is a side view of a scooter-type motorcycle 1 according to an embodiment to which the invention is applied.
[0018]
In this embodiment, the directions of front, rear, left, and right are determined with reference to the directions in a state that a rider faces the advancing direction of a vehicle. A vehicle front portion 1f and a vehicle rear portion 1r are connected to each other by way of a low floor portion lc, and a vehicle body frame which constitutes a skeleton of the vehicle body is substantially constituted of a down tube 3 and a main pipe 4.
[0019]
That is, the down tube 3 extends downwardly from a head pipe 2 of the vehicle body front portion 1f, the down tube 3 has a lower end thereof bent in the horizontal direction and extends rearwardly below the floor portion 1c, and a pair of left and right main pipes 4 is connected to a rear end of the down tube 3. Here, the main pipes 4 rise in the obliquely and rearward direction from the connection portion and is bent in the horizontal direction at a predetermined height, and the main pipes 4 extend rearwardly.
[0020]

A fuel tank 5 and the like are supported on the main pipe 4 and a seat 6 is arranged above the fuel tank 5 and the like.
On the other hand, in the vehicle body front portion 1f, a handle 11 is arranged above the vehicle body front portion 1f in a state that the handle 11 is supported on the head pipe 2, a front fork 12 extends below the vehicle body front portion 1f, and a front wheel 13 is pivotally supported on a lower end of the front fork 12. [0021]
A bracket 15 is mounted on a lower end of a rising portion of the main pipe 4 in a projecting manner, and a swing unit 17 is connected to and supported on the bracket 15 by way of a link member 16 in a rockable manner. [0022]
A single-cylinder four-stroke-cycle internal combustion engine 30 is mounted on a front portion of the swing unit 17 in a state that the internal combustion engine 30 has a cylinder block 32 thereof largely inclined frontwardly close to a substantially horizontal posture, and an end portion of a hanger bracket 18 which projects frontwardly from a lower end of a portion which corresponds to a crankcase of a unit swing case 31 is connected to the link member 16 by way of a pivot shaft 19. [0023]
A belt-type continuously variable transmission 35 is

arranged in a state that the transmission 35 extends rearwardly from the internal combustion engine 30 and a rear wheel 21 is pivotally supported on a speed reduction mechanism 38 which is mounted on a rear portion of the belt-type continuously variable transmission 35.
A rear cushion 22 is interposed between an upper end of the speed reduction mechanism 38 and the upper bent portion of the main pipe 4. [0024]
On an upper portion of the swing unit 17, a carburetor 24 which is connected to an intake pipe 23 which extends from an upper portion of the cylinder head 33 of the internal combustion engine 30 and an air cleaner 25 which is connected to the carburetor 24 are arranged. [0025]
On the other hand, an exhaust pipe 2 6 which extends from a lower portion of the cylinder head 33 extends downwardly while being offset to a right side and is curved rearwardly in a state that the exhaust pipe 2 6 wraps around the right-side hanger bracket 18. The exhaust pipe 26 extends rearwardly below a radiator 110 which is mounted on a right side of a portion corresponding to the crankcase described later, and is connected to the muffler 27.
The muffler 27 is mounted on the unit swing case 31 in a suspended manner using a bracket 28 and is arranged on a right

side of the rear wheel 21. [0026]
The vehicle body front portion 1f is covered with a front cover 9a and a leg shield 9b from a front side and a rear side thereof and is covered with a front lower cover 9c from left and right sides thereof, and a center portion of the handle 11 is covered with a handle cover 9d.
The floor portion 1c is covered with a side cover 9e and a vehicle body rear portion lr is covered with a body cover 10 from left and right sides thereof. [0027]
Fig. 2 is a longitudinally cross-sectional view of the swing unit 17.
The unit swing case 31 is formed by joining a left unit case 31L and a right unit case 31R which are split in the lateral direction, wherein the right unit case 31R constitutes a half body of the crankcase portion, and the left unit case 31L is constituted of a longitudinally elongated crankcase portion 31a which is arranged at a front portion of the left unit case 31L , a power transmission case portion 31b which is arranged at a center portion of the left unit case 31L and a speed-reduction gear case portion 31c which is arranged at a rear portion of the left unit case 31L. [0028]
A left-side open surface of the left unit case 31L is

covered with a power transmission case cover 36 which constitutes a portion of a power transmission case, the belt-type continuously variable transmission 35 is housed in the inside of the left unit case 31L. Further, a right-side open surface of a rear speed reduction gear case portion 31c is covered with a speed-reduction gear case 37 and a speed reduction mechanism 38 is housed in the inside of the rear speed reduction gear case portion 31c. [0029]
In the inside of the crankcase portion 31a and the right unit case 31R, that is, in the inside of the crankcase, a crankshaft 40 is rotatably supported on left and right main bearings 41, 41, an AC generator 60 is mounted on a right extending portion out of extending portions which extend in the laterally horizontal direction, and a cam chain drive sprocket wheel 55 and a belt drive pulley 76 of the belt-type continuously variable transmission 35 are mounted on the left extending portion. [0030]
In the internal combustion engine 30, a piston 42 which reciprocates in the inside of a cylinder liner 44 of the cylinder block 32 and a crank pin 40a of the crankshaft 40 are connected to each other using a connecting rod 43. [0031]
The four-cycle internal combustion engine 30 of the

invention adopts an SOHC-type valve system. Here, a valve operating mechanism 50 is provided in the inside of the cylinder head cover 34 . A cam chain 51 which transmits a driving power to the valve operating mechanism 50 is extended between a cam shaft 53 and the crankshaft 40, while a cam chain chamber 52 for the cam chain 51 is provided in a state that the cam chain
52 is communicable with the crankcase portion 31a, the cylinder block 32 and the cylinder head 33.
[0032]
That is, the cam chain 51 is extended between a driven sprocket wheel 54 which is fitted on a left end of the cam shaft
53 directed in the laterally horizontal direction and the drive sprocket wheel 55 which is fitted on the crankshaft 40 while passing through the inside of the cam chain chamber 52.
In the cylinder head 33, an ignition plug 45 is fitted in a combustion chamber from a side (right side) opposite to the cam chain chamber 52.
[0033]
As shown in Fig. 3, the valve operating mechanism 50 which is provided in the inside of the cylinder head cover 34 has a cylinder thereof largely inclined frontwardly to a substantially horizontal state and hence, an intake valve 56 and an exhaust valve 57 are arranged above and below the cam shaft 53, and rocker arms 59, 59 are pivotally mounted on upper and lower rocker shafts 58, 58 respectively in a rockable manner.

Here, the rocker arms 59, 59 are rocked due to the rotation of the cam of the cam shaft 53 and allow the intake valve 56 and the exhaust valve 57 to perform open/close operations at predetermined timings. [0034]
To further explain in conjunction with Fig. 2, in the crankcase portion 31a of the unit swing case 31, the cam chain chamber 52 is formed in a state that the cam chain chamber 52 is partitioned from the crank chamber by the main bearing 41, and a left-side wall of the cam chain chamber 52 constitutes a partition wall 71 which divides a belt-type continuously variable transmission chamber 70 which is arranged at a further left side of the cam chain chamber 52 and the cam chain chamber 52. Here, a circular penetration hole 71a having a large-diameter flattened cylindrical shape into which the crankshaft 40 penetrates is formed in the partition wall 71, a circular annular seal member 72 is press-fitted in the penetration hole 71a and the crankshaft 40 penetrates a hollow portion of the circular annular seal member 72. [0035]
The drive sprocket wheel 55 is fitted on the crankshaft 40 which is arranged between the seal member 72 and the main bearing 41 and the cam chain 51 is wrapped around the drive sprocket wheel 55.
The belt-type continuously variable transmission

chamber 70 is water-tightly separated from the cam chain chamber 52 using the seal member 72 and hence, it is possible to prevent oil from leaking into the belt-type continuously variable transmission chamber 70. [0036]
A belt drive pulley 76 is mounted on the crankshaft 40 which penetrates the seal member 72 and extends in a state that the belt drive pulley 76 can be rotated together with the crankshaft 40. [0037]
The belt drive pulley 76 is constituted of a fixed-side pulley half body 77 and a movable-side pulley half body 78. Here, the fixed-side pulley half body 77 is fixedly secured to the crankshaft 40 in a state that a boss 79 is sandwiched between the fixed-side pulley half body 77 and a left end portion of the crankshaft 40, while the movable-side pulley half body 7 8" is supported on the crankshaft 40 by way a boss 79 in a right side of the fixed-side pulley half body 77 . The movable-side pulley half body 78 is rotatable together with the crankshaft 40 and is slidable in the axial direction of the crankshaft 40 to approach or move away from the fixed-side pulley half body 77, and a V belt 75 is wrapped around and is sandwiched between both pulley half bodies 77, 78. [0038]
A cam plate 80 is arranged at a fixed position in the

vicinity of the annular-shaped seal member 72 on a right side of the movable-side pulley half body 78. Here, a slide piece 80a which is mounted on an outer peripheral end of the cam plate 80 is slidably engaged with a cam plate sliding boss portion 78a which is formed on an outer peripheral end of the movable-side pulley half body 78 in the axial direction.
A side surface of the movable-side pulley half body 78 on the cam plate 80 side is tapered toward the cam plate 80 side and a dry weight roller 81 is housed in a state that the dry weight roller 81 is sandwiched between the cam plate 80 and an inner surface side of the tapered surface. [0039]
Accordingly, when a rotational speed of the crankshaft 40 is increased, the dry weight roller 81 which is arranged between the movable-side pulley half body 78 and the cam plate 80 and is rotated together with the movable-side pulley half body 78 and the cam plate 80 moves in the centrifugal direction due to a centrifugal force. Then, the movable-side pulley half body 78 is pushed by the dry weight roller 81 and is moved leftwardly to approach the fixed-side pulley half body 77 so as to allow the V belt 75 which is sandwiched between both pulley half bodies 77, 78 to move in the centrifugal direction thus increasing a wrapping diameter of the V belt. [0040]
In a rear-side belt driven pulley 86 which corresponds

to the above-mentioned belt drive pulley 76, a fixed-side pulley half body 87 is fitted on an inner sleeve 89 which is relatively rotatably supported on a speed reduction gear input shaft 92 of the speed reduction mechanism 38, while a movable-side pulley half body 88 is fitted on an outer sleeve
90 which is slidably supported on the inner sleeve 89 in the axial direction on a left side of the fixed-side pulley half body 87. That is, the belt driven pulley 86 is constituted of both pulley half bodies 87, 88.
The above-mentioned V belt 75 is sandwiched between both pulley half bodies 87, 88. [0041]
A centrifugal clutch 91 is provided to left portions of the speed reduction gear input shaft 92 and the inner sleeve 89. Here, the power which is transmitted to the inner sleeve 89 by way of the V belt 75 is, and when the rotational speed of the inner sleeve 89 is increased, the centrifugal clutch
91 is joined to the speed reduction gear input shaft 92 and hence, the power is transmitted to the speed reduction gear input shaft 92.
[0042]
In the speed reduction mechanism 38, the power which is transmitted to the speed reduction gear input shaft 92 is transmitted to an output shaft 94 by way of an intermediate shaft 93 in deceleration due to meshing of gears, and the output

shaft 94 constitutes a rear axle, that is, an axle of the rear wheel 21 which rotates the rear wheel 21.
A drum brake 95 is mounted on a hub portion of the rear wheel 21. [0043]
On the other hand, in the AC generator 60 which is mounted on the right-side surface of the right unit case 31R, a bowl-shaped outer rotor 62 is fixedly secured to an end portion of the crankshaft 40 which projects from a center cylindrical portion 31d of the right unit case 31R by way of an ACG boss 61, a stator 64 around which a stator coil 65 is wrapped is fixed to the center cylindrical portion 31d inside of magnets 63 which are mounted on an inner peripheral surface of the outer rotor 62 along the circumferential direction. [0044]
A radiator fan 66 is mounted on a right side surface of the outer rotor 62, and a fan cover 100 surrounds an outer periphery of the radiator fan 66.
Further, a radiator 110 is arranged close to a side of the radiator fan 66, and the radiator 110 is covered with a first radiator cover 120 in cooperation with a second radiator cover 130 from a right side. [0045]
A state that a fan cover 100 is mounted on the right-side surface of the right unit case 31R is shown in Fig. 3.

The fan cover 100 is constituted such that a flange wall 102 which is arranged close to the left end surface of a flattened-cylindrical-shaped peripheral wall 101 which surrounds the outer periphery of the radiator fan 66 on the right unit case 31R side slightly extends toward a center axis and a large circular opening 103 is formed in a center of the fan cover 100. [0046]
A center of the circular opening 103 is the axis of the crankshaft and also is the center of rotation of the radiator fan 66, and an outer diameter of the radiator fan 66 is made slightly small than an inner diameter of the circular opening 103. [0047]
The peripheral wall 101 which surrounds an outer periphery of the radiator fan 66 is formed in a vortex shape in which a distance (radius) between the center of the crankshaft and the peripheral wall 101 is gradually increased from an upper portion of the small diameter of the peripheral wall 101 to a lower portion of the peripheral wall 101 in the rotational direction (in Fig. 3, the clockwise direction) of the radiator fan 66, wherein at the lower portion of the peripheral wall 101, the distance becomes largest.
Here, a cutout portion l0lx is formed by partially cutting out a front portion of the peripheral wall 101.

[0048]
Further, a lower rear portion 102a of the flange wall 102 which is arranged close to the left end surface on the right unit case 31R side partially bulges close to a right end surface on an outside (radiator 110 side), and a stepped portion 102b is formed in an obliquely inclined manner on a boundary
(substantially undermost position) between the flange wall 102 arranged close to the left end surface and the lower rear portion 102a arranged close to the right end surface,
[0049]
An exhaust port 105 is formed in the stepped portion 102b and, further, a plurality of exhaust ports 106 are formed in a rear portion of the peripheral wall 101 of the fan cover 100.
[0050]
In an outer periphery of the peripheral wall 101 of the fan cover 100, boss portions 107 for mounting the fan cover 100 orr the right unit case 31R are formed in four places, and the fan cover 100 is fastened to the right unit case 31R by allowing bolts 107b to penetrate mounting hol.es of the boss portions 107 (see, Fig. 3).
[0051]
Further, brackets 108 which respectively project in the substantially vertical direction from four corners, that is, upper, lower, front and rear corners are formed on the fan cover 100 . In distal ends of the brackets 108, female threaded holes

108a tor mounting tne radiator 110 on the ran cover 100 are formed. Further, in distal end portions of brackets 109 which respectively project in the substantially longitudinal direction from two upper front and rear portions and one lower front portion, female threaded holes 109a for mounting a first radiator cover 120 on the fan cover 100 are formed. [0052]
The radiator 110 which is mounted on the fan cover 100 fastened to the right unit case 31R is, as shown in Fig. 7 (see Fig. 5, Fig. 6), configured such that a radiator core portion 111 having a rectangular shape is sandwiched between the upper radiator tank portion 112 and the lower radiator tank portion 113. Here, although the heat-radiation-use radiator core portion 111 is made of metal (aluminum), the upper radiator tank portion 112 and the lower radiator tank portion 113 are made of a synthetic resin thus realizing the reduction of weight of the radiator 110. [0053]
In the upper radiator tank portion 112, a replenishing port 112a of the cooling water extends upwardly and an opening thereof is closed by a filler cap 115, and a cooling water introducing port 112b projects backwardly (left side) (see Fig. 5) .
Here, mounting brackets 112c which are respectively mounted on front and rear ends of the longitudinally-elongated

upper radiator tank portion 112 are formed while including mounting holes 112d. [0054]
On the other hand, in the lower radiator tank portion 113, a drain cock 113a is mounted on the right-side surface of the lower radiator tank portion 113 and is arranged close to a rear side of the right side surface, and a cooling water lead-out port 113b projects forwardly.
Further, mounting brackets 113c which include mounting holes 113d are mounted on the right side surface of the lower radiator tank portion 113 such that the mounting brackets 113c are respectively arranged close to a front portion and an a rear end portion of the lower radiator tank portion 113. [0055]
The upper radiator tank portion 112 of the radiator 110 is covered with a metal-made second radiator cover 130 from a right side of the vehicle body (in Fig. 5, left side) (see Fig. 5, Fig, 6).
The second radiator cover 130 is, as shown in Fig. 8 and Fig. 9, constituted of a cover body portion 131 which is formed of an outer wall 131a having the substantially same profile as the upper radiator tank portion 112 and a peripheral wall 131b and a strip-like stay portion 132 which forms mounting brackets 132a on both front and rear end portions thereof in a state that the mounting brackets 132a include mounting holes

132b. [0056]
The cover body portion 131 has the outer wall 131a thereof formed in conformity with the right side surface of the upper radiator tank portion 112 and has the peripheral wall 131b formed in conformity with the upper surface to the front and rear side surfaces of the upper radiator tank portion 112. [0057]
Accordingly, the cover body portion 131 has a portion of an upper side of the peripheral wall 131b thereof cut out while avoiding the replenishing port 112a and has a lower portion thereof bulged outwardly, wherein front and rear sides of the lower portion are particularly largely bulged to form a cutout space above the front and rear sides. [0058]
The cover body portion 131 according to the above-mentioned embodiment covers the longitudinally elongated upper radiator tank portion 112 from a right side and hence, the cover body portion 131 can cover a substantially right half side of the upper radiator tank portion 112.
At a middle height position above the lower bulged portion of the outer wall 131a of the cover body portion 131, a strip-like shallow groove 131c is formed in the longitudinal direction. [0059]

On the other hand, the stay portion 132 is bent in a U-shape to be fitted in the groove 131c of the cover body portion
131 and sandwich the cover body portion 131 from front and rear sides. Further, the mounting brackets 132a arranged on both end portions of front and rear portions of the stay portion
132 are bent in the frontward and rearward directions and are extended vertically downwardly.
Here, portions of lower ends of the front and rear mounting brackets 132a are bent rightwardly to form welding members 132c. [0060]
When the stay portion 132 is fitted in the groove 131c of the cover body portion 131 and sandwiches the cover body portion 131 from the front and rear sides, the mounting brackets 132a formed on the front and rear both ends of the stay portion 132 are positioned in spaces above the front and rear bulged portions formed on the lower portion of the cover body portion 131, and the welding members 132c are brought into contact with upper surfaces of the bulged portions. Accordingly, by welding the contact portions and by also welding the stay portion 132 which is brought into contact with the groove 131c of the cover body portion 131, the cover body portion 131 and the stay portion 132 are integrally joined to each other thus forming the second radiator cover 130. [0061]

The second radiator cover 130 is formed by joining the cover body portion 131 and the stay portion 132 to each other and hence, the cover body portion 131 can be easily formed by drawing thus maintaining a high accuracy of dimensions of the mounting holes 132b of the mounting brackets 132a formed on the front and rear both ends of the stay portion 132. [0062]
Further, the stay portion 132 is fitted in and welded to the groove 131c arranged at the middle height position of the cover body portion 131 and hence, the middle height position of the second radiator cover 130 forms the duplicate structure in which the cover body portion 131 and the stay portion 132 are overlapped to each other thus enhancing strength of the second radiator cover 130. [0063]
The above-mentioned second radiator cover 130 is mounted on the fan cover 100 along with the mounting of the radiator 110. [0064]
That is, when the radiator 110 is overlapped to the fan cover 100 at a predetermined position so as to cover the radiator fan 66, mounting holes 112d, 113d formed in the mounting brackets 112c, 113c which are arranged at four corners of the radiator 110 are aligned with the four radiator-mounting-use female threaded holes 108a formed in the

fanrcover 100. Further, when the upper radiator tank portion 112 of the radiator 110 is covered with the second radiator cover 130 from a right side, the mounting holes 132b formed in of the front and rear end brackets 132a which are formed on the stay portion 132 of the second radiator cover 130 are aligned with the mounting holes 112d formed in the mounting brackets 112c arranged at front and rear sides of the upper radiator tank portion 112. [0065]
Accordingly, by allowing flange bolts 140 to penetrate the front and rear mounting holes 112d of the upper radiator tank portion 112 and the front and rear mounting holes 132b of the second radiator cover 130 which are aligned with the two radiator-mounting-use female threaded holes 108a arranged on the upper side of the fan cover 100, and by engaging the flange bolts 140 with the female threaded holes 108a for fastening and,at the same time, by allowing flange bolts 141 to penetrate the front and rear mounting holes 113d of the lower radiator tank portion 113 which are aligned with two radiator-mounting-use female threaded holes 108a formed in the lower side of the fan cover 100, and by engaging the flange bolts 141 with the female threaded holes 108a by fastening, as shown in Fig. 4, the radiator 110 is mounted on the fan cover 100 together with the second radiator cover 130. [0066]

The second radiator cover 130 is fastened to the fan cover 100 together with the radiator 100 and hence, it is possible to decrease man-hours for assembling.
The synthetic-resin-made upper radiator tank portion 112 of the radiator 110 is covered with the metal-made second radiator cover 130 and hence, the synthetic-resin-made upper radiator tank portion can be protected easily. [0067]
The right unit case 31R mounts a water pump 150 thereon in front of the AC generator 60 and a thermostat 151 is mounted along a right side surface of the water pump 150 in a projecting manner, and a portion of the thermostat 151 is positioned so as to compensate for the cutout portion 101X of the peripheral wall 101 of the fan cover 100. [0068]
To further explain in conjunction with Fig. 4, the cooling water which is cooled by the radiator 110 is introduced into the above-mentioned thermostat 151 from the lower radiator tank portion 113 through a connection hose 152 (see Fig. 7) .
A water passage in which cooling water is supplied to the cylinder bock 32 of the internal combustion engine 30 through a connection pipe 153 using the water pump 150 and passes through the cylinder block 32 is formed from the thermostat 151, and a water passage in which the cooling water introduced to the cylinder head 33 from the cylinder block 32

returns to the upper radiator tank portion 112 of the radiator
110 through a connection hose 154 is formed.
[0069]
A bypass hose 155 is branched or bifurcated from a middle portion of the connection hose 154, and the bypass hose 155 is connected to the thermostat 151 thus forming a water passage which detours without passing through the radiator 110. [0070]
In the idling of the internal combustion engine 30 which is performed when the engine 3 0 is not yet warmed, the thermostat 151 closes the water passage through which the cooling water from the radiator 110 flows and opens the water passage which is bypassed from the cylinder head 33 so as to accelerate the idling using the water passage which does not allow the cooling water to pass through the radiator 100 . When the idling is finished and the normal operation starts, the thermostat 151 closes the water passage which is bypassed from the cylinder head 33 and opens the water passage through which the cooling water from the radiator 110 flows so as to circulate the cooling water cooled by the radiator 110 to the cylinder head 33 from the cylinder block 32 thus cooling the cylinder head 33. [0071]
The radiator 110 which constitutes the above-mentioned cooling system constitution and is mounted together with the

second radiator cover 130 is covered with the synthetic-resin-made first radiator cover 120 from a right side. [0072]
The first radiator cover 120 is, as shown in Fig. 10 (see Fig. 5, Fig. 6), constituted of a core cover portion 121 in which a louver 122 which covers the radiator core portion 111 of the radiator 110 from a right side is supported on an annular portion 121a, an upper tank cover portion 123 which is arranged above the core cover portion 121 and covers portions from a right-side surface and an upper surface to front and rear surfaces of the upper radiator tank portion 112, a lower tank cover portion 124 which is arranged below the core cover portion 121 and covers portions from a right side surface and a lower surface to the front and rear surfaces of the lower radiator tank portion 113, and an extending cover portion 125 which covers the thermostat 151 frontwardly from the core cover portion 121. [0073]
The mounting boss portions 12 0a is mounted on three positions (two positions of the front and rear positions at the upper side and one position of the front position at the lower side) arranged on an outer periphery of the annular portion 121a of the core cover portion 121 while including the mounting holes 120b.

When the radiator 110 which is mounted on the fan cover 100 together with the second radiator cover 130 is covered with the first radiator cover 120 from a right side, whole radiator
110 is covered, the mounting holes 120b of the mounting boss portions 120a arranged at the three positions of the first radiator cover 120 are aligned with the female threaded holes 109a of the brackets 109 arranged on the three positions of the fan cover 100. Accordingly, by allowing the bolts 142 to penetrate the mounting holes 120b and by engaging the bolts 142 with the female threaded holes 109a for fastening, as shown in Fig. 1, the first radiator cover 120 can be mounted on the radiator 110 in a state that the first radiator cover 120 is overlapped to the radiator 110.
[0074]
When the radiator fan 66 is rotated along with the rotation of the crankshaft 40 of the internal combustion engine 30/ air is introduced from the louver 122 of the first radiator cover 120 arranged on the right side of the vehicle body, and the introduced air passes through the radiator core portion
111 of the radiator 110 thus cooling the cooling water which flows in the radiator core portion 111.
[0075]
What appears on an appearance of the cover which covers the radiator 110 is the synthetic-resin-made first radiator cover 120 and hence, it is possible to simplify the surface

finishing of the second radiator cover 130 thus realizing the
reduction of cost.
[0076]
As shown in Fig. 1, below the lower tank cover portion 124 of the synthetic-resin-made first radiator cover 120 which covers the longitudinally elongated lower radiator tank portion 113 of the radiator 110, the exhaust pipe 26 is arranged in a state that the exhaust pipe 26 is directed in the longitudinal direction and hence, the lower radiator tank portion 113 can be protected from an external force such as flying pebbles and the like using the exhaust pipe 26 together with the first radiator cover 120. [0077]
The upper radiator tank portion 112 of the radiator 110 is covered with the first radiator cover 120 and the metal-made second radiator cover 130 in a duplicate manner and hence, the upper radiator tank portion 112 can be protected from an external force specifically using the metal-made second radiator cover 130. [0078]
Further, since the upper radiator tank portion 112 is a tank to which the cooling water which becomes high temperature after cooling the cylinder head 33 and the like returns by circulation, the temperature of the tank per se becomes high. However, first of all, the upper radiator tank portion 112 is

covered with the metal-made second radiator cover 130 and, thereafter, the outside of the second radiator cover 130 is covered with the first radiator cover 120 and hence, the metal-made second radiator cover 130 is interposed whereby it is possible to reduce the influence of heat to the synthetic-resin-made first radiator cover 120. [0079]
The reduction of the weight of the radiator 110 is realized by forming the upper radiator tank portion 112 and the lower radiator tank portion 113 using the synthetic resin except for the radiator core portion 111. Here, with respect to the covers which protect the radiator 110, only the second radiator cover 130 which covers only the synthetic-resin-made upper radiator tank portion 112 is made of metal, and the first radiator cover 120 which covers the substantially whole radiator 110 is made of the synthetic resin and hence, the reduction of weight of the radiator 110 can be "maintained as much as possible. [0080]
Further, the exhaust pipe 26 is arranged below the synthetic-resin-made lower radiator tank portion 113 and hence, it is possible to effectively protect the radiator 110 while maintaining the reduction of weight. [Brief Description of the Drawings] [0081]

[Fig . 1 ] A whole side view of a scooter-type motorcycle according to an embodiment of the invention.
[Fig. 2] A longitudinally cross-sectional view of a swing unit.
[Fig. 3] A right side view with a part in cross section of a swing unit in a state that a fan cover is mounted on a front half portion of the swing unit.
[Fig. 4] A right side view of the front half portion of the swing unit in a state that a radiator and the like are mounted on the front half portion of the swing unit.
[Fig. 5] An exploded front view of the radiator, a second radiator cover and a first radiator cover.
[Fig. 6] An exploded plan view of the radiator, the second radiator cover and the first radiator cover.
[Fig. 7] A right side view of the radiator.
[Fig. 8] A right side view of the second radiator cover.
[Fig. 9] An exploded perspective view of the second radiator cover.
[Fig. 10] A right side view of the first radiator cover. [Description of Reference Numerals and Signs] [0082]
1: scooter-type motorcycle 17: swing unit 26: exhaust pipe 27: muffler

30: internal combustion engine
31: unit swing case
32: cylinder block
33: cylinder head
34: cylinder head cover
40: crankshaft
60: AC generator
66: radiator fan
100: fan cover
101: peripheral wall
102: flange wall
103: circular opening
107: mounting boss portion
108: bracket
108a: female threaded hole
109: bracket
109a: female threaded hole
110: radiator
111: radiator core portion
112: upper radiator tank portion
113: lower radiator tank portion
120: first radiator cover
120a: mounting boss portion
120b: mounting hole
121: core cover portion

122: louver
123: upper tank cover portion
124: lower tank cover portion
125: extending cover portion
130: second radiator cover
131: cover body portion
132: stay portion



[Designation of Document] Claims [Claim 1]
A radiator cover structure of a small-sized vehicle in which a radiator is constituted of a heat-radiation-use radiator core portion and a pair of synthetic-resin-made radiator tank portions which is connected to the radiator core portion and performs supplying and discharging of cooling water, wherein
a synthetic-resin-made first radiator cover in which a cooling wind passage is formed in a state that the cooling wind passage faces the radiator core portion in an opposed manner covers the radiator, and
a metal-made second radiator cover covers the radiator tank portion in cooperation with the first radiator cover. [Claim 2]
A radiator cover structure of a small-sized vehicle according to claim 1, wherein the first radiator cover covers the second radiator cover. [Claim 3]
A radiator cover structure of a small-sized vehicle according to claim 2, wherein the second radiator cover covers the radiator tank portion and, at the same time, the second radiator cover is fastened to the radiator together with the radiator tank portion. [Claim 4]

A radiator cover structure of a small-sized vehicle according to claim 3, wherein the radiator arranges the radiator tank portions at upper and lower portions thereof, the second radiator cover covers only the upper radiator tank portion, and an exhaust pipe is arranged below the lower radiator tank portion. [Claim 5]
A radiator cover structure of a small-sized vehicle according to claim 3, wherein the second radiator cover is constituted by integrally joining a cover body portion which is formed of an outer wall and a peripheral wall having the substantially same profile as the radiator tank portion and a strip-like stay portion which forms mounting holes in both end portions thereof to each other.
Dated this 1 day of November 2006

Documents:

2007-che-2006-abstract.image.jpg

2007-che-2006-abstract.pdf

2007-che-2006-claims.pdf

2007-che-2006-correspondnece-others.pdf

2007-che-2006-description(complete).pdf

2007-che-2006-drawings.pdf

2007-che-2006-form 1.pdf

2007-che-2006-form 26.pdf

2007-che-2006-form 3.pdf

2007-che-2006-form 5.pdf

EXAMINATION REPORT REPLY.PDF


Patent Number 238266
Indian Patent Application Number 2007/CHE/2006
PG Journal Number 6/2010
Publication Date 05-Feb-2010
Grant Date 28-Jan-2010
Date of Filing 01-Nov-2006
Name of Patentee HONDA MOTOR CO., LTD
Applicant Address 1-1, MINAMI-AOYAMA 2-CHOME, MINATO-KU, TOKYO 107-8556.
Inventors:
# Inventor's Name Inventor's Address
1 IKEDA, TSUGIO C/O HONDA R&D CO., LTD, 4-1, CHUO 1-CHOME, WAKO-SHI, SAITAMA 351-0193.
PCT International Classification Number F01P11/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2005-318455 2005-11-01 Japan