JP2008050006A - Heat shielding structure of fuel tank for scooter type vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily manufacture heat shielding plates for a fuel tank at a low cost. <P>SOLUTION: A scooter type vehicle with a low floor including a radiator arranged on a vehicle front part of a vehicle body frame and the fuel tank arranged in the vicinity of the radiator is provided with down tubes hung down obliquely downwardly from a head pipe of the vehicle body frame and with upper tubes extended rearwardly at a gradient gentler than that of the down tube. The fuel tank is a container integrated by superposing a tank lower half of a front lower half and a tank upper half of a rear upper half and jointing flange portions. The line of the flange portion passes through the approximately intermediate position between the inclination line of the down tube and the inclination line of the upper tube in side view. The fuel tank is provided with the heat shielding plates arranged along the bottom face inclination of the tank lower half. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat shield structure for a fuel tank for a scooter type vehicle.

  Scooter type vehicles include a relatively large vehicle equipped with a water-cooled engine, an engine cooling radiator, and a large-capacity fuel tank. In such a scooter type vehicle, in order to increase the cooling efficiency of the radiator, a layout in which the radiator is arranged at the front part of the vehicle body and the engine is arranged behind the radiator is widely adopted. Furthermore, a large fuel tank may be placed close to the radiator or engine due to the arrangement space. In such an arrangement relationship, the fuel tank is affected by heat from the radiator and the engine, and thus countermeasures are required. For example, Patent Document 1 is known as a technique for preventing the influence of heat from an engine or a radiator. (Hereafter referred to as “conventional technology”.)

  In the prior art, as shown in FIG. 2 of the publication, a radiator 26 (the number is cited in the publication, the same applies hereinafter) is arranged at the front part of the vehicle body, and the engine 20 is arranged at the rear part of the vehicle body. The present invention also relates to a motorcycle in which a fuel tank 30 is disposed between the radiator 26 and the engine 20.

Furthermore, as shown in FIGS. 2 to 4 of the above publication, the above-mentioned conventional technique covers a fuel tank 30 from above with a cylindrical fuel tank cover 40 whose upper surface is closed. In this state, the fuel tank 30 is attached to the vehicle body frame. It is to attach. By doing so, the fuel tank cover 40 can prevent the thermal effect exerted on the fuel tank 30 from the engine 20 and the radiator 26. The fuel tank cover 40 is an integrally molded product of a soft resin.
Japanese Unexamined Patent Publication No. 2000-229593 (FIGS. 2 to 4)

  However, the conventional fuel tank cover 40 is a large member because it covers the fuel tank 30. In order to integrally mold such a large cover, a large molding die is required, which increases the manufacturing cost. Moreover, it is not always easy to manufacture the fuel tank cover 40 having a complicated shape that matches the shape of the fuel tank 30.

  An object of the present invention is to provide a technique capable of easily and inexpensively manufacturing a heat shield plate for a fuel tank.

  The invention according to claim 1 is a scooter type vehicle having a low floor type floor in which a radiator is disposed at a vehicle body front portion of a vehicle body frame and a fuel tank is disposed in the vicinity of the radiator, and is inclined from a head pipe of the vehicle body frame. The fuel tank is provided with a down tube that hangs downward and an upper tube that extends rearward with a gentler inclination than the down tube. The fuel tank has a flange portion that overlaps the lower half of the tank in the front lower half and the upper half of the tank in the rear upper half. The flange part line passes through the middle of the down tube inclination line and the upper tube inclination line in a side view, and is arranged along the bottom inclination of the bottom half of the tank. A heat shield is provided.

  The invention according to claim 2 is characterized in that the upper end of the heat shield plate is curved toward the upper side of the radiator, and the lower end thereof is a hard resin sheet extending to at least the lower portion of the radiator.

  The invention according to claim 3 is characterized in that the heat shield plate is detachably attached to a cross member connecting the left and right down tubes.

  The invention according to claim 4 includes a down tube that hangs downward from the head pipe, and a left and right floor support stay that is bolted to the front and rear brackets that are formed in a horizontal portion of the down tube and supports the low floor type floor. The tank and the radiator are arranged between the left and right floor support stays.

  In the invention according to claim 5, the upper bracket is spanned between the left and right stays provided at the upper portions of the left and right down tubes, the lower bracket is provided at the lower portions of the left and right down tubes, and the upper portion of the flange of the fuel tank is attached to the upper bracket. The fuel tank is detachably attached to the vehicle body frame by bolting and bolting the lower part of the flange to the lower bracket.

  The invention according to claim 6 is characterized in that a water-cooled engine is provided, which is tilted forward with respect to the cylinder head and arranged substantially horizontally after the fuel tank.

  In the invention according to claim 7, the return pipe for returning the coolant from the engine to the radiator extends along the horizontal portion of one of the down tubes, and is connected to the left and right sides of the radiator to supply the coolant from the radiator to the engine. The supply pipe extends from the other side of the radiator along the horizontal portion of the other down tube and is connected to the liquid inlet of the engine, and the return pipe and the supply pipe are arranged in the vicinity of both ends of the heat shield plate. To do.

  The invention according to claim 8 is provided with a supply port on the inclined upper surface of the fuel tank and a tray covering the periphery of the supply port, one end of the fuel discharge hose is connected to the tray, and the other end is released to the atmosphere. The tray is sandwiched between the upper surface of the fuel tank and the vehicle body cover.

  In the invention according to claim 1, the fuel tank is a container integrated by overlapping the lower half of the tank in the front lower half and the upper half of the tank in the rear upper half and joining the flange parts, and the line of the flange parts Is equipped with a heat shield that passes through the middle of the inclined line of the down tube and the inclined line of the upper tube in side view and is arranged along the bottom inclined surface of the lower half of the tank. Thus, while ensuring the tank capacity, the fuel tank can be arranged so that the flange does not interfere with the frame, and the fuel tank can be effectively shielded from heat.

  In the invention according to claim 2, since the upper end of the heat shield plate is curved toward the upper side of the radiator and the lower end is a hard resin sheet extending at least to the lower portion of the radiator, the heat shield plate is simple and effective for radiator heat. It can be made into a shape that can shield heat.

  In the invention which concerns on Claim 3, since a heat shield is detachably attached to the cross member which connects a right and left down tube, attachment of a heat shield becomes easy.

  The invention according to claim 4 includes a down tube that hangs downward from the head pipe, and left and right floor support stays that are bolted to the front and rear brackets that are formed in the horizontal portion of the down tube and support the low floor type floor. Since the tank and the radiator are disposed between the left and right floor support stays, the fuel tank and the radiator can be effectively protected.

  In the invention according to claim 5, the upper bracket is spanned between the left and right stays provided at the upper portions of the left and right down tubes, the lower bracket is provided at the lower portions of the left and right down tubes, and the upper portion of the flange of the fuel tank is attached to the upper bracket. Since the fuel tank is detachably attached to the vehicle body frame by bolting and fixing the lower part of the flange to the lower bracket, the large-capacity fuel tank can be firmly fixed.

  In the invention according to claim 6, since the water-cooled engine with the cylinder head inclined forward and disposed substantially horizontally is provided after the fuel tank, the cylinder is effectively arranged while the large-capacity fuel tank is mounted. be able to.

  In the invention according to claim 7, the return pipe for returning the coolant from the engine to the radiator extends along the horizontal portion of one of the down tubes, is connected to one of the left and right sides of the radiator, and supplies the coolant from the radiator to the engine. The supply pipe extends from the left and right other sides of the radiator along the horizontal portion of the other down tube and is connected to the liquid inlet of the engine, and the return pipe and the supply pipe are disposed near both ends of the heat shield plate. It is possible to arrange the heat shield plate in consideration of the above.

  In the invention according to claim 8, the fuel tank is provided with a supply port and a tray covering the periphery of the supply port on the inclined upper surface of the fuel tank, one end of the fuel discharge hose is connected to the tray, and the other end is released to the atmosphere. Since the tray is sandwiched between the upper surface of the fuel tank and the vehicle body cover, bolts or the like for mounting the tray are not necessary, and mounting is easy.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. Note that “front”, “rear”, “left”, “right”, “upper”, and “lower” follow the direction seen from the driver. The drawings are to be viewed in the direction of the reference numerals.
FIG. 1 is a left external view of a motorcycle according to the present invention, and shows that the motorcycle 10 is a scooter type vehicle having a low floor type floor 25.

  A body cover 20 that covers the entire body frame of the motorcycle 10 includes a front cowl 21 that covers a front portion of the body frame and an upper portion of the front wheel, which will be described later, an upper cover 22 that covers an upper opening of the front cowl 21, and a rear portion of the front cowl 21. An inner cover 23 that covers the vehicle body, a center cover 24 that extends rearward from the rear end of the inner cover 23 to cover the longitudinal center of the vehicle body frame, and a low-floor type that extends outward from the lower edge of the center cover 24 and rests the driver's feet. A floor 25, a floor skirt 26 extending downward from the outer edge of the low floor type floor 25, a rear side cover 27 extending rearward from the center cover 24 and covering the rear side of the vehicle body frame, and rearward from the rear end of the rear side cover 27 And a rear cover 28 covering the rear part of the extended body frame.

The front cowl 21 includes a transparent wind screen 31 at the top. The inner cover 23 includes a leg shield 91 that covers the front part of the driver's legs.
The motorcycle 10 further includes a handle 203 at the front of the vehicle body and a seat 208 and a step holder 300 at the rear of the vehicle body.

  The handle 203 has a shape in which the grips 203a and 203a are made relatively high and pulled backward. The handle 203 was covered with the handle cover 101. The handle cover 101 includes a lower handle cover 102 that covers the left and right lower portions of the handle 203 and an upper handle cover 103 that covers the upper portion of the handle 203.

The seat 208 is a double seat composed of a seat front portion 208a where a driver sits and a seat rear portion 208b where an occupant sits. The step holder 300 is disposed adjacent to the rear portion of the center cover 24, and is provided with a pillion step (passenger step) 310 on which a rider puts his / her foot so as to be stored and exposed.
In the figure, 261 is a headlamp, 262 is a blinker, 263 and 263 are mirrors, 264 is a front fender, 265 is a seat lock lock, 266 is a rear air spoiler, 267 is a tail lamp, 268 is a rear fender, 269 is a sub stand, 320 Is the main stand.
Reference numerals 271 and 272 denote master cylinders, which generate braking hydraulic pressure by operating the brake levers 273 and 274.

FIG. 2 is a right external view of the motorcycle according to the present invention, and shows that a meter panel 92 is provided at the upper part of the front cowl 21 and at the rear of the wind screen 31. As is clear from the above description, the wind screen 31, the leg shield 91, and the meter panel 92 can be provided at the front of the vehicle body.
Furthermore, this figure shows that the step holder 300 including the pillion step 310 is also arranged on the right side of the motorcycle 10. Reference numeral 275 denotes an exhaust silencer.

FIG. 3 is a side sectional view of the motorcycle according to the present invention, and the motorcycle 10 is viewed from the left side.
The motorcycle 10 includes a body frame 110, a front fork 201 attached to the head pipe 111 of the body frame 110 so as to be able to swing left and right, a front wheel 202 attached to the front fork 201, the handle 203 connected to the front fork 201, An engine 211 attached to the rear part of the body frame 110, a power transmission mechanism 212 that can swing up and down around the crankshaft of the engine 211 independently of the engine 211, and a rear wheel 205 attached to the rear part of the power transmission mechanism 212, The rear cushion unit 206 in which the rear end portion of the power transmission mechanism 212 is suspended from the vehicle body frame 110, the storage box 207 attached to the rear upper part of the vehicle body frame 110, and the above-described arrangement that is disposed on the storage box 207 and can be opened and closed. The seat 208 is a main component. Over a data-type vehicle.

The front fork 201 is a gate-type fork arranged below the head pipe 111. The upper portion of the front fork 201 and the head pipe 111 are covered with the front cowl 21.
The engine 211 is a water-cooled two-cylinder engine in which the two left and right cylinder heads 215 are slightly inclined toward the front upper direction and are arranged substantially horizontally.
The power transmission mechanism 212 is a belt converter continuously variable transmission with a centrifugal clutch that transmits the power of the engine 211 to the rear wheel 205.

The storage box 207 is a box elongated in the front-rear direction of the vehicle body so that two helmets Hf and Hr can be stored in the front and rear, and the upper box 207b superimposed on the rear upper part of the lower box 207a and the lower box 207a. It consists of.
In the figure, 281 is an air cleaner disposed on the side of the storage box 207, 282 is a connecting tube, 283 is an air chamber disposed in front of the storage box 207, 284 is a throttle valve, 285 is an inlet pipe, and 286 is a battery. is there.

  FIG. 4 is a perspective view of the vehicle body frame according to the present invention. The vehicle body frame 110 includes a front frame 112 connected to the head pipe 111 and a pair of left and right rear frames 115 and 115 extending rearward from the rear portion of the front frame 112. It is a double cradle type integrated frame joined by welding. The head pipe 111 includes a cowl stay bracket 111a.

  The front frame 112 hangs a pair of left and right upper frames 113, 113 rearward and downward from the head pipe 111, and a pair of left and right down tubes 114, 114 downward from the head pipe 111 below the pair of upper frames 113, 113. The lower ends of the pair of down tubes 114 and 114 are extended rearward to be coupled to the lower ends of the pair of upper frames 113 and 113, and further extended rearward and upward. Since the front frame 112 has such a configuration, it is possible to provide a space portion Sp1 that is surrounded by the pair of upper frames 113 and 113 and the pair of down tubes 114 and 114 and has a substantially triangular shape in side view.

  Between the front end of the left rear frame 115 and the front end of the right rear frame 115, a front-view type first cross member 121 is spanned, and the lower end of the left upper frame 113 and the lower end of the right upper frame 113 are The second cross member 122 is spanned between the two, and the engine first bracket 123 is coupled to the center position of the second cross member 122 in the vehicle width direction.

  A third cross member 124 is bridged between the rear end portion of the horizontal portion of the left down tube 114 and the rear end portion of the horizontal portion of the right down tube 114, and the vehicle width center position of the third cross member 124 is determined. In addition, the second bracket for engine 125 is coupled, and the left and right third engine brackets 126, 126 are coupled to the rear ends of the left and right down tubes 114, 114, respectively.

  The pair of left and right rear frames 115 and 115 is a member having a vertically long cross-sectional shape in which one end is coupled to the middle of the pair of left and right upper frames 113 and 113 and the other end extends rearward. Here, the “longitudinal cross-sectional shape” means a cross-sectional shape having a vertical dimension larger than the horizontal dimension. Specifically, the rear frames 115 and 115 are formed of square pipes having a vertically long rectangular cross section.

The present invention is characterized in that three cross members 131 to 133 are detachably spanned between a pair of left and right rear frames 115, 115. Specifically, a front rear cross member 131, a middle rear cross member 132, and a rear rear cross member 133 are spanned in this order from the front between the left and right rear frames 115, 115.
These three cross members 131 to 133 are overlapped with the upper surfaces of the rear frames 115 and 115 and bolted. Since the rear frames 115 and 115 are square pipes, it is easy to mount the three cross members 131 to 133 in a mounted state.

  The front rear cross member 131 is a frontal portal-type member, and extends a rear opening U-shaped stay 131a in a plan view from the left and right standing parts, and a seat hinge support portion at the front end of the U-shaped stay 131a. In addition to coupling 131b, an extension member 131c extends forward from the front end of the U-shaped stay 131a, and the first cross member 121 is bolted to the front end of the extension member 131c. The middle rear cross member 132 is a bar-shaped member, and the rear rear cross member 133 is a front-open U-shaped member in plan view.

  Further, left and right cushion brackets 134, 134 are coupled to the rear portions of the left and right rear frames 115, 115, and a rear lower rear cross member 135 having a substantially U-shape in front view is interposed between the rear portions of the left and right rear frames 115, 115. After that, the left and right transport hooks 136 and 136 are coupled to the lower rear cross member 135.

In this figure, a pair of left and right floor support stays 141 and 141 and an underframe 143 are detachably attached to the vehicle body frame 110, and a plurality of headed pins 144 (... indicates a plurality, the same applies hereinafter). It shows that.
More specifically, the left and right floor support stays 141 and 141 are members that support the low floor type floor 25 (see FIG. 1), and are bolted to the brackets 145, 145, 146, and 146 of the left and right down tubes 114 and 114, respectively. It is a member to be stopped.
The right floor support stay 141 is a member in which an engine ignition coil 226 is detachably attached to the lower portion of the front end via a stay 142 with bolts 227 and 227. The ignition coil 226 attached to the lower part of the down tube 114 is disposed below the low floor type floor 25.

The underframe 143 is a member suspended so as to be hung between the horizontal portions of the left and right down tubes 114 and 114 and is bolted to the brackets 146, 146, 147 and 147 of the down tubes 114 and 114. .
Such an underframe 143 includes left and right side members 143a, 143a extending along the horizontal portion of the down tubes 114, 114, and a central cross member 143b spanned between the longitudinal center portions of the side members 143a, 143a, It consists of a rear cross member 143c spanned between the rear ends of the side members 143a and 143a. Reference numeral 148 denotes a hook that holds a heat shield plate for a fuel tank, which will be described later.

  The headed pins 144 are members for holding a heat shield for a fuel tank, which will be described later. The left and right upper frames 113, 113, the outer portions of the left and right down tubes 114, 114, and the front left and right of the first cross member 121. A total of six are provided. In the figure, 151 is a front cross member, and 152, 152, and 153 are stays.

  FIG. 5 is a left side view of the vehicle body frame, engine, power transmission mechanism, and seat according to the present invention. The engine 211 and the power transmission mechanism 212 are disposed behind the front frame 112 and below the pair of rear frames 115, 115. It shows that the engine 211 is mounted in the vicinity of the connection portion between the front frame 112 and the left and right rear frames 115, 115 (only shown on the left in the figure, the same applies hereinafter).

  Specifically, a space portion Sp2 having a substantially triangular shape in side view is provided at the rear portion of the front frame 112 and surrounded by the pair of upper frames 113 and 113, the pair of down tubes 114 and 114, and the pair of rear frames 115 and 115. The cylinder head 215 and the head cover 216 of the engine 211 are disposed in the space Sp2, the front lower portion of the engine 211 is attached to the first bracket 123 for the engine, and the rear lower portion of the engine 211 is attached to the second bracket 125 for the engine. The rear upper part of the engine 211 is attached to the third brackets 126, 126 for the engine. The front and middle rear cross members 131 and 132 are disposed above the engine 211.

  Further, (1) the rear end of the power transmission mechanism 212 is suspended from the left and right cushion brackets 134, 134 via the left and right rear cushion units 206, 206, and (2) the front rear cross member 131. Indicates that it also serves as a member that supports the seat hinge 208c of the openable seat 208. In this way, the rear cushion units 206 and 206 and the seat 208 can be supported by the rear frames 115 and 115.

FIG. 6 is a side sectional view of the front lower portion of the motorcycle according to the present invention, as seen from the left side of the motorcycle 10, and the engine 211 is installed at the rear of the low floor type floor 25 shown by an imaginary line. The engine cooling radiator 221 is disposed at the front portion of the floor 25, the ignition coil 226 is disposed at the lower front portion of the floor 25, and the fuel tank 230 is disposed between the engine 211 and the radiator 221. .
In other words, the radiator 221 is disposed in front of the engine 211 and in front of the left and right down tubes 114 and 114 (shown only on the left in the figure, the same applies hereinafter).

  The return pipe 222 that returns the coolant from the engine 211 to the radiator 221 is a hose that passes from the center of the vehicle width to the left (front side in the figure). Specifically, the return pipe 222 connected to the liquid return port of the engine 211 extends along the horizontal portion of the left down tube 114 and the drooping portion of the front portion thereof, and is connected to the upper header 221a of the radiator 221.

  On the other hand, the supply pipe 223 that supplies the coolant from the radiator 221 to the engine 211 is a hose that passes from the center of the vehicle width to the right (the side in the figure). Specifically, the supply pipe 223 connected to the lower header 221b of the radiator 221 extends rearward along the horizontal portion of the right down tube 114 (the side facing the drawing) and is connected to the liquid inlet of the engine 211. Reference numeral 224 denotes a radiator fan.

The ignition coil 226 is characterized in that it is disposed at the right position (the opposite side in the drawing) opposite to the return pipe 222 with respect to the vehicle width center and in front of the radiator 221.
In this way, the ignition coil 226 is placed at a position where (1) it is not affected by the heat from the engine 211, (2) at a position where it is not affected by the heat of the exhaust air from the radiator 221, and (3) from the return pipe 222. It can be arranged at a position not affected by heat.

The fuel tank 230 is disposed in a substantially triangular space Sp1 surrounded by a pair of left and right upper frames 113 and 113 and a pair of left and right down tubes 114 and 114 in a side view. Such a fuel tank 230 is arranged along the upper frames 113 and 113 and the down tubes 114 and 114 when viewed from the side of the vehicle body as shown in FIG. It is a container that is tapered forward. Furthermore, in order to increase the capacity of the fuel tank 230, the lower part extends below the down tubes 114, 114. By covering the lower part of the fuel tank 230 extending downward from the down tubes 114 and 114 with a detachable underframe 143, the fuel tank 230 can be protected.
The underframe 143 is attached to the body frame 110 after the fuel tank 230 is inserted and attached to the space Sp <b> 1 from below the body frame 110.

FIG. 7 is a perspective view around the fuel tank in the present invention.
The fuel tank 230 is a container integrated by overlapping the lower half portion 231 of the front lower half and the upper half portion 232 of the rear upper half and joining the flange 233 portion, and fuel is supplied to the inclined upper surface 230a. A port 234, a breather sub-tank 235, and a fuel supply pump 236 are provided. Specifically, the breather sub-tank 235, the fuel filler port 234, and the fuel supply pump 236 are arranged in this order from the upper front to the lower rear in the upper part of the fuel tank 230.

  The flange 233 has one mounting hole 233a in the upper center portion, and two mounting holes 233b (only one on the left is shown in this figure) on the left and right sides of the lower portion. The oil filler port 234 includes a sealed cap 237. The breather sub-tank 235 is a small container that communicates with the fuel tank 230.

In the present invention, four heat shield plates denoted by reference numerals 241, 242, 243, and 243 are provided for preventing thermal effects from the engine 211, the radiator 221, the return pipe 222, and the supply pipe 223 (see FIG. 6). The heat insulating plates 241, 242, 243, and 243 are divided into members and arranged on the front surface, rear surface, left surface, and right surface of the fuel tank 230.
Since the divided heat shield plates 241, 242, 243, and 243 are taken into consideration, the degree of thermal influence from the engine 211 and the radiator 221 is taken into account, and the size is arbitrarily and minimally adapted to the shape of each surface of the fuel tank 230. Can be stopped. As a result, each of the heat shield plates 241, 242, 243, and 243 is relatively small and can be manufactured very easily. In addition, the molding die can be small and the material can be small, so that it can be manufactured at low cost.

  The front heat shield 241 that covers the front surface of the fuel tank 230 is a resin sheet such as a hard resin that has a substantially rectangular shape when viewed from the front. The front heat shield 241 made of a resin sheet has a very simple shape and can be manufactured at a lower cost.

The rear heat shield 242 that covers the rear surface of the fuel tank 230 is a generally rectangular rubber sheet, and has two left and right hooking holes 242a and 242a in the upper part and one hooking hole 242b in the lower part. Have.
The left and right heat shield plates 243 and 243 covering the lower half of the left surface and the lower half of the right surface of the fuel tank 230 are rubber sheets having two hooking holes 243a and 243a in the upper part. The left and right heat shield plates 243 and 243 are disposed between the fuel tank 230, the return pipe 222, and the supply pipe 223 (see FIG. 6). In this way, the heat of the return pipe 222 and the supply pipe 223 is prevented from being transmitted to the fuel tank 230.
As described above, the rear heat shield plate 242 and the left and right heat shield plates 243 and 243 can be freely deformed because they are rubber sheets, and can be freely arranged according to the space around the fuel tank 230. In addition, the narrow space around the fuel tank 230 can be used effectively and can be arranged easily. Furthermore, since the rear heat shield 242 and the left and right heat shields 243 and 243 are made of a sheet, the shape is extremely simple, and it can be manufactured at a lower cost.

Here, returning to FIG.
The front heat shield 241 is disposed between the down tube 114 and the fuel tank 230 that hangs downward from the head pipe 111 and is detachably attached to the front cross member 151 so that it also serves as a wind guide for the radiator 221. It is a member. For this reason, the upper end of the front heat shield plate 241 curves to the upper side of the radiator 221, and the lower end of the front heat shield plate 241 extends to below the radiator 221.
Thus, since the front heat shield 241 is disposed between the down tube 114 and the fuel tank 230, the front heat shield 241 can be easily attached to the down tube 230. Therefore, the mounting workability of the front heat shield 241 is good.

The rear heat shield plate 242 can be detachably attached to the vehicle body frame 110 by hooking the upper part to the headed pin 144 and hooking the lower part to the hook 148.
Further, the left and right heat shield plates 243 and 243 (only shown on the left in this figure) can be detachably attached to the vehicle body frame 110 by hooking the upper portions thereof with the headed pins 144.

  As is clear from the above description, since the heat shield plates 241, 242, 243, 243 are divided, the heat shield plates 241, 242, 243, 243 are mounted after the fuel tank 230 is attached to the vehicle body frame 110 (vehicle body). Can be freely attached to the vehicle body frame 110, and the attachment workability is good.

This figure shows that the front of the radiator 221 is covered with the front lower cover 93 and the underside of the radiator 221 and the fuel tank 230 is covered with the under cover 94.
The front lower cover 93 extends to the front end of the under cover 94 and includes a plurality of radiator air guide ports 93a.
The under cover 94 includes an exhaust port 94a below the fan 224 in order to exhaust the exhaust air from the radiator 221 to the outside. The air exhaust port 94a includes a large number of louvers (rectifying plates) 94b.

  Further, this figure shows a refueling lid 330 that is opened when fuel is supplied to the fuel tank 230 through the refueling port 234, and an inspection lid 360 that is opened when the ignition plug (not shown) of the engine 211 is inspected. The cover 20 is provided.

FIG. 8 is a view taken in the direction of arrow 8 in FIG. 6 and shows a structure in which a fuel tank 230 is attached to the vehicle body frame 110.
The body frame 110 has an upper bracket 154 spanned between left and right stays 152 and 152 and lower brackets 155 and 155 attached to the left and right down tubes 114 and 114. The upper part of the flange 233 of the fuel tank 230 is bolted to the upper bracket 154, and the lower part of the flange 233 is bolted to the lower brackets 155 and 155, so that the fuel tank 230 can be detachably attached to the vehicle body frame 110. . Note that the upper part of the flange 233 is a bolt fastened to the upper bracket 154.

  FIG. 9 is a cross-sectional view taken along line 9-9 of FIG. 8 and shows that the lower bracket 155 is rubber-mounted by attaching the lower part of the flange 233 via a rubber bush 156 with bolts and nuts 157. Reference numeral 158 denotes a color.

  FIG. 10 is a front sectional view of the motorcycle. (1) The vehicle body frame 110 and the fuel tank 230 are covered with a center cover 24, left and right floors 25, 25, left and right floor skirts 26, 26, and an under cover 94. And (2) the floors 25, 25 are bolted to the left and right down tubes 114, 114 via the floor support stays 141, 141.

As described above, the left and right heat shields 243 and 243 suspended on the headed pins 144 are suspended along the side of the fuel tank 230, and the side surface of the fuel tank 230 and the down tubes 114 and 114 are Extending through the gaps between them. As described above, since the upper portions of the left and right heat shield plates 243 and 243 are only hooked on the vehicle body frame 110, the mounting is simple.
Upper portions of the left and right heat shield plates 243 and 243 are attached to the outer surfaces of the upper frames 113 and 113, and lower portions thereof are disposed inside the down tubes 114 and 114, the return pipe 222, and the supply pipe 223. Therefore, the heat of the return pipe 222 and the supply pipe 223 can be prevented from reaching the fuel tank 230.

  FIG. 11 is an operational view around the radiator according to the present invention. A fan 224 behind the radiator 221 sucks wind from the front of the radiator 221. Therefore, the outside air becomes cooling air (including traveling air during vehicle travel) Fc and enters the radiator air guide port 93a, enters the radiator 221 through the cooling air passage.

Hot air (exhaust wind hot air) Fh passing through the radiator 221 is discharged from the fan 224, guided by a front heat shield 241 that also serves as a wind guide, and changes its flow downward, from the exhaust port 94a of the under cover 94 to the outside. leak.
Since the direction of the hot air Fh that has passed through the radiator 221 is changed by the front heat shield plate 241, the influence of the hot air Fh on the engine 211 and the fuel tank 230 behind the radiator 221 can be prevented. Further, since the front heat shield 241 also serves as a wind guide, there is no need to provide a different wind guide.

FIG. 12 is a schematic diagram of a fuel tank according to the present invention. The fuel tank 230 is provided with a tray 251 that surrounds the fuel filler port 234, and one end 252 a of a fuel discharge hose (drain hose) 252 is connected to the tray 251. The other end 252b of the fuel discharge hose 252 is opened to the atmosphere.
As described above, the breather sub-tank 235 communicates with the fuel tank 230. One end 253a of the breather hose 253 is connected to the breather sub tank 235, and the other end of the breather hose 253 is bifurcated. Reference numeral 254 denotes a T joint that branches the other end of the breather hose 253.

  FIG. 13 is a rear cross-sectional view around the fuel filler opening of the fuel tank according to the present invention, and the tray 251 is a fuel tray in which a cylindrical portion 251b penetrating vertically is formed integrally with a flat bottom 251a. The tray 251 is attached by inserting the cylindrical portion 251b into the fuel filler opening 234 and sandwiching the upper and lower surfaces of the bottom 251a between the bottom 24b of the recess 24a provided in the fueling portion of the center cover 24 and the upper surface 230a of the fuel tank 230. Can do. Therefore, a member such as a bolt for attaching the tray 251 is not required, and attachment is easy. Reference numeral 24c denotes a fuel filler through hole.

FIG. 14 is a right side external view of the vehicle body frame and the fuel tank according to the present invention. The tray 251 includes a discharge port 251c extending rearward and downward. One end 252a of the fuel discharge hose 252 is connected to the discharge port 251c, the fuel discharge hose 252 is suspended along the right upper frame 113, extends to the rear right end portion of the under cover 94, and the other end 252b. Turn down.
While the fuel tank 230 is being refueled, the fuel spilled around the refueling port 234 can be received by the tray 251 and discharged outside via the fuel discharge hose 252. Therefore, there is no concern that the outer surface of the fuel tank gets wet with spilled fuel.

On the other hand, the breather sub-tank 235 includes a breather port 235a extending rightward. One end 253a of the breather hose 253 is connected to the breather port 235a, and the breather hose 253 is hung downward and downward along the right side surface of the fuel tank 230.
That is, after the breather hose 253 extends along the fuel tank 230 between the upper frame 113 and the down tube 114 to the right end portion of the rear cover 94 when the fuel tank 230 is viewed from the front. Branch into a bifurcated shape.
One branched other end 253b extends to the rear left end portion of the under cover 94 and is opened to the atmosphere, and the other branched other end 253c once extends upward along the rear surface of the fuel tank 230. It extends rearward along the left upper frame 113 and opens to the atmosphere. Therefore, even if one of the two other ends 253b and 253c is clogged, the breather function can be secured by the other one.

In the above-described embodiment of the present invention, the ignition coil 226 may be disposed at a position opposite to the return pipe 222 with respect to the vehicle width center. For example, the return pipe 222 is passed to the right from the vehicle width center. In this case, it may be arranged on the left side.
Moreover, what is necessary is just to arrange | position the divided heat-shielding board to the front surface and the rear surface of the fuel tank 230 at least.

  The heat shield structure of the fuel tank for a scooter type vehicle of the present invention is suitable for a scooter type vehicle.

Left side view of motorcycle according to the present invention Right side external view of motorcycle according to the present invention Side sectional view of a motorcycle according to the present invention. The perspective view of the body frame concerning the present invention Left side view of body frame, engine, power transmission mechanism and seat according to the present invention Side sectional view of the lower front portion of the motorcycle according to the present invention. The perspective view around the fuel tank in the present invention 8 arrow view of FIG. Sectional view taken along line 9-9 in FIG. Front sectional view of motorcycle Action diagram around the radiator according to the present invention Schematic diagram of a fuel tank according to the present invention Cross-sectional view of the back of the fuel tank and its surroundings of the fuel tank according to the present invention Right external view of body frame and fuel tank according to the present invention

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Scooter type vehicle (motorcycle), 25 ... Low floor type floor, 110 ... Body frame, 111 ... Head pipe, 114 ... Down tube, 211 ... Engine, 221 ... Radiator, 230 ... Fuel tank, 241-243 ... Blocking Heat plate (front heat shield, rear heat shield, left / right heat shield).

Claims (8)

A scooter-type vehicle having a low floor type floor in which a radiator is disposed at a vehicle body front portion of a body frame and a fuel tank is disposed in proximity to the radiator,
A down tube that hangs obliquely downward from the head pipe of the vehicle body frame, and an upper tube that extends rearward with a gentler inclination than the down tube,
The fuel tank is a container integrated by overlapping the lower half of the tank in the front lower half and the upper half of the tank in the rear upper half and joining the flange portions,
The flange portion line includes a heat shield plate that is disposed along the bottom slope of the lower half of the tank, passing through substantially the middle of the inclined line of the down tube and the inclined line of the upper tube in a side view. A heat shield structure for a fuel tank for a scooter type vehicle.   2. The scooter type fuel tank for a scooter type vehicle according to claim 1, wherein an upper end of the heat shield plate is curved toward an upper side of the radiator, and a lower end thereof is a hard resin sheet extending to at least a lower portion of the radiator. Thermal structure.   2. The heat shield structure for a scooter type vehicle fuel tank according to claim 1, wherein the heat shield plate is detachably attached to a cross member connecting the left and right down tubes.   The fuel tank and the radiator are provided with a down tube that hangs downward from the head pipe, and left and right floor support stays that are bolted to front and rear brackets that are formed in a horizontal portion of the down tube and support the low floor type floor. The scooter type vehicle fuel tank heat insulating structure according to claim 1, characterized in that is disposed between the left and right floor support stays.   The upper bracket is bridged between the left and right stays provided at the upper part of the left and right down tubes, the lower bracket is provided at the lower part of the left and right down tubes, the upper part of the flange of the fuel tank is bolted to the upper bracket, and the lower bracket is attached. 2. The heat insulation structure for a fuel tank for a scooter type vehicle according to claim 1, wherein the fuel tank is detachably attached to the vehicle body frame by bolting a lower portion of the flange.   2. The heat insulation structure for a scooter type fuel tank for a scooter type vehicle according to claim 1, further comprising a water-cooled engine having a cylinder head inclined forward and disposed substantially horizontally after the fuel tank.   A return pipe for returning the coolant from the engine to the radiator extends along the horizontal portion of one of the down tubes and is connected to one of the left and right sides of the radiator. A supply pipe for supplying the coolant from the radiator to the engine is provided on the left and right sides of the radiator. 2. The pipe according to claim 1, wherein the return pipe and the supply pipe are arranged in the vicinity of both ends of the heat shield plate, extending from the other side along the horizontal portion of the other down tube and connected to the liquid inlet of the engine. Heat insulation structure for scooter type vehicle fuel tank.   The fuel tank is provided with a supply port on the inclined upper surface of the fuel tank and a tray covering the supply port, and one end of a fuel discharge hose is connected to the tray and the other end is released to the atmosphere. The heat insulating structure for a fuel tank for a scooter type vehicle according to claim 1, wherein the structure is sandwiched between the vehicle body cover and the vehicle body cover.

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