Seat rail structure in scooter type vehicle

Abstract: To ensure the detachability of a tank disposed below a seat and increase the capacity of the tank. A seat frame 62 is detachably fixed by bolts 65 and 66 to the upper portion of a rear frame 61, and a seat 16 is supported to the upper portion of the seat rail 62. An oil tank 67 and a fuel tank 68 are disposed in the space surrounded by the rear frame 61 and the seat rail 62. A projection 68 3 is formed on each side surface of the fuel tank 68 so as to project between the rear frame 61 and the seat rail 62, thereby increasing the capacity of the fuel tank 68. When the seat rail 62 is removed from the rear frame 61, the tanks 67 and 68 can be mounted and removed without interference with the seat rail 62.

Description: The present invention relates to a scooter type vehicle comprising a seat rail provided on an upper portion of a frame to support a seat, and a tank formed of synthetic resin and located in a space surrounded by the frame and the seat rail, In such a scooter type vehicle, it is necessary that a fuel tank and an oil tank have complicated shapes, so as to avoid interference with other accessories or the like and ensure the capacity of each tank. To this end, each tank is sometimes formed by blow molding of synthetic resin. Such a tank formed of synthetic resin is less strong than a tank formed of metal, so that a seat cannot be supported directly on the upper surface of the synthetic resin tank. Conventionally, the seat is supported on a seat rail provided on a frame, and the tank is located in a space surrounded by the frame and the seat rail. However, in such an arrangement that the tank is located in the space surrounded by the frame and the seat rail, it must be considered that the tank does not interfere with the seat rail in mounting or removing the tank for assembly or maintenance. As a result, the shape and size of the tank are limited to cause a problem that a sufficient capacity of the tank cannot be ensured in some case. It is accordingly an object of the present invention to ensure the detachability of a tank disposed below a seat and increase the capacity of the tank in a scooter type vehicle with the seat supported to an upper portion of a seat rail. To achieve the above object, the invention as defined in the preamble of claim 1 is characterized in that said seat rail is detachable from said frame. According to the invention as defined in claim 1, the tank formed of synthetic resin and disposed in the space surrounded by the frame and the seat rail can be easily mounted and removed without interference with the seat rail by removing the seat rail from the frame. As a result, the degree of freedom of designing the shape and size of the tank can be increased to thereby ensure an enough capacity of the tank. The particular embodiment of the invention as defined in claim 2 inclusive of the configuration of claim 1 is characterized in that the seat rail is formed in a U-shape as viewed in plan so as to cover a front surface and right and left side surfaces of the tank. According to the configuration of claim 2, the tank can be protected by the seat rail covering the front surface and the right and left side surfaces of the tank. The invention as defined in claim 3 inclusive of the configuration of claim 1 is characterized in that a projection is formed on each side surface of the tank so as to project between the frame and the seat rail both extending along each side surface of the tank. According to the invention as defined in claim 3, the projection is formed on each side surface of the tank so as to project between the frame and the seat rail both extending along each side surface of the tank. Accordingly, the dead space between the frame and the seat rail can be utilized to allow an increase in capacity of the tank. A preferred embodiment of the present invention will now be described with reference to the drawings. FIGS. 1 to 8 show a preferred embodiment of the present invention, in which FIG. 1 is a left side view of a motorcycle; FIG. 2 is an enlarged view of an essential part in FIG. 1; FIG. 3 is an enlarged view of an essential part of the motorcycle as viewed from the right side thereof; FIG. 4 is an enlarged cross section taken along the line 4-4 in FIG. 2; FIG. 5 is an enlarged view of an essential part in FIG. 2; FIG. 6 is a cross section taken along the line 6-6 in FIG. 5; FIG. 7 is a cross section taken along the line 7-7 in FIG. 5; and FIG. 8 is a cross section taken along the line 8-8 in FIG. 2. As shown in FIG. 1, a scooter type motorcycle V includes a front wheel Wf and a rear wheel Wr at the front and rear portions of a vehicle body. The front wheel Wf is rotatably supported through an axle to the lower ends of a front fork 2 adapted to be turned to the right or the left by a steering handle 1. The upper side of the front wheel Wf is covered with a front fender 3. The steering handle 1 is provided with a headlight 4 and a rearview mirror 5. A swing unit S is vertically swingably supported to the vehicle body and is suspended by a pair of right and left cushions 6. The swing unit S includes at its front portion an engine E and at its rear portion a transmission case 7. The rear wheel Wr is rotatably supported through an axle to the rear end of the transmission case 7. An air cleaner 8 is provided on the left side of the swing unit S, and a muffler 9 is provided on the right side of the swing unit S. Supported to a vehicle frame F are a leg shield 10 for covering the front side of rider's legs, a floor panel 11 for supporting rider's feet, a rear cover 12 for covering the rear portion of the vehicle body, and a rear fender 13 for covering the upper side of the rear wheel Wr. A front carrier 14 and a front pocket 15 are provided on the front surface and the rear surface of the leg shield 10, respectively. A seat 16 and a rear carrier 17 are provided on the upper surface of the rear cover 12 at its front portion and rear portion, respectively. A main stand 18 is provided at the lower portion of the vehicle frame F. The structure of the swing unit S will now be described with reference to FIGS. 2 to 4. The engine E includes a left crankcase half 23 and a right crankcase half 24 for supporting both end portions of a crankshaft 21 through a pair of ball bearings 22. A transmission case body 25 for storing a belt type continuously variable transmission T is formed integrally with the rear portion of the left crankcase half 23. A transmission case cover 26 is corrected to a left open end of the transmission case body 25, and a speed reducer cover 27 is connected to the right side surface of the transmission case body 25 at its rear portion. The belt type continuously variable transmission T stored in the space defined by the transmission case body 25 and the transmission case cover 26 includes a drive pulley 28 mounted on the left end of the crankshaft 21 as an input shaft and having a groove whose width is variable by a centrifugal force, an output shaft 30 supported through a pair of ball bearings 29 to the transmission case body 25 and the speed reducer cover 27, a driven pulley 31 mounted on the output shaft 30 so as to be rotatable relative thereto, an automatic centrifugal clutch 32 mounted on the output shaft 30 and capable of connecting the driven pulley 31 to the output shaft 30, and an endless belt 33 wrapped between the drive pulley 28 and the driven pulley 31. The transmission case cover 26 is provided with a kick starter 35 having a kick pedal 34. An axle 37 of the rear wheel Wr is supported through a pair of ball bearings 36 to the transmission case body 25 and the speed reducer cover 27. The axle 37 is connected through a speed reducer 38 to the output shaft 30. The speed reducer 38 is stored in the space defined between the transmission case body 25 and the speed reducer cover 27, and includes a first gear 39 mounted on the output shaft 30, a second gear 41 and a third gear 42 both mounted on an intermediate shaft 40, and a fourth gear 43 mounted on the axle 37. A wheel 44 of the rear wheel Wr is splined to a portion of the axle 37 projecting rightward from the speed reducer cover 27. The transmission case 7 is disposed on the left side of a laterally central plane of the vehicle body, that is, on the left side of an axially central plane of the rear wheel Wr, and a swing arm 45 is disposed on the right side of the laterally central plane of the vehicle body. The swing arm 45 is a substantially triangular platelike member integrally formed by aluminum die casting. The swing arm 45 is connected at its front portion relatively wide in the vertical direction to the right crankcase half 24 of the engine E by a pair of upper and lower bolts 46 and 47. The axle 37 is supported at its right end through a ball bearing 48 to the rear portion of the swing arm 45. The swing arm 45 is formed with three openings 45 1 , 45 2 , and 45 3 arranged in the longitudinal direction. The three openings 45 1 to 45 3 are isolated from each other by two columns 45 4 and 45 5 inclined frontward at their upper portions. The front opening 451 has a substantially triangular shape, and the central and rear openings 45 2 and 45 3 have a substantially parallelogrammic shape. The swing unit S has a highly rigid box structure formed by the engine E on the front side, the axle 37 on the rear side, the transmission case 7 on the left side, and the swing arm 45 on the right side. The front end of the swing unit S is pivotably supported through a link 49 to the vehicle frame F, and the rear end of the swing unit S is suspended from the vehicle frame F through the left cushion 6 connected to a cushion boss 25 1 formed at the rear portion of the transmission case body 25 and the right cushion 6 connected to a cushion boss 45 6 formed at the rear portion of the swing arm 45. The muffler 9 is connected at its front end to the rear end of an exhaust pipe 50 extending from the engine E to the right side of the vehicle body. A triangular mounting stay 51 is welded to the front portion of the muffler 9. The mounting stay 51 is secured to the engine E by the two bolts 46 and 47 connecting the swing arm 45 to the engine E. Thus, the muffler 9 can be supported with a reduced number of parts. The mounting stay 51 is formed with a triangular opening 51 1 . As mentioned above, the swing arm 45 and the mounting stay 51 both disposed along the right side surface of the transmission case 7 have the openings 45 1 to 45 3 and 51 1 , respectively. Accordingly, there hardly occurs the resonance of engine noise and vehicle running noise in the space surrounded by the transmission case 7 and the swing arm 45, thereby reducing noises due to the resonance. Furthermore, the front end of the swing arm 45 is connected to the engine E by the two, upper and lower bolts 46 and 47, thereby enough ensuring the rigidity against a vertical load input from the rear wheel Wr. In addition, the swing arm 45 has a ladder-like configuration formed by the three openings 45 1 to 45 3 and the two columns 45 4 and 45 5 , thereby reducing the weight of the swing arm 45 owing to the lightening effect by the openings 45 1 to 45 3 and simultaneously obtaining high rigidity of the swing arm 45. In FIG. 2, reference numeral 52 denotes a carburetor disposed between the air cleaner 8 and the engine E, and reference numeral 53 denotes a duct for introducing a cooling air from the inside of the vehicle frame F to the inside of the transmission case 7. The structure of the rear portion of the vehicle body will now be described with reference to FIGS. 5 to 8. The vehicle frame F has a pair of right and left rear frames 61 rising on the front side of the swing unit S and extending rearward. A seat rail 62 is composed of a seat supporting portion 63 having a U-shape as viewed in plan and a pair of right and left leg portions 64 extending downward from the seat supporting portion 63. The right and left, rear ends of the seat supporting portion 63 is detachably connected by two bolts 65 to two brackets 61 1 provided on the two rear frames 61, and the lower ends of the two leg portions 64 are detachably connected by two bolts 66 to two brackets 61 2 provided on the two rear frames 61. An oil tank 67 formed of synthetic resin and a fuel tank 68 formed of synthetic resin are disposed in tandem in the space surrounded by the rear frames 61 and the seat rail 62. A bracket 67 1 integrally formed with and projecting from the lower surface of the oil tank 67 is fixed by a bolt 73 to a bracket 72 of a cross member 71 connecting the right and left rear frames 61. A platelike tray 74 is substantially horizontally disposed so as to cover an upper opening of the rear cover 12. The tray 74 is formed with an opening 74 1 from which a cap 75 for openably closing an oil filler opening of the oil tank 67 is exposed to project upward. On the other hand, a pair of right and left brackets 68 1 integrally formed with and projecting from the right and left side surfaces of the fuel tank 68 at its front portion are fixed by two bolts 77 through two rubber bushings 76 to two brackets 61 3 provided on the two rear frames 61. Further, a pair of right and left brackets 68 2 integrally formed with and projecting from the rear surface of the fuel tank 68 are fixed by two bolts 79 through two rubber bushings 78 to a bracket 61 4 extending between the two rear frames 61. A fuel level sensor 80 and a cap 81 for openably closing a fuel filler opening of the fuel tank 68 project upward from the upper surface of the fuel tank 68. The fuel level sensor 80 is fitted within a hollow projection 74 2 formed on the upper surface of the tray 74, and the cap 81 is exposed to project from an opening 74 3 formed through the tray 74. The right and left side walls of the fuel tank 68 are formed with right and left projections 68 3 projecting rightward and leftward of the vehicle body, respectively. As apparent from FIG. 6, the projections 68 3 of the fuel tank 68 overlap the rear frames 61 and the seat rail 62 as viewed in plan. That is, the projections 68 3 project sideward of the vehicle body so as to be fitted within the right and left spaces between the rear frames 61 and the seat supporting portion 63 of the seat rail 62, thereby allowing an increase in capacity of the fuel tank 68. With this arrangement, when the detachable seat rail 62 is removed from the rear frames 61, the fuel tank 68 having the projections 68 3 can be mounted to and removed from the rear frames 61 without interference with the seat rail 62. As a result, the degree of freedom of designing the shapes and sizes of the oil tank 67 and the fuel tank 68 disposed inside the seat rail 62 can be greatly increased to ensure the capacities of the oil tank 67 and the fuel tank 68 to the maximum. Furthermore, the side portions of the oil tank 67 and the fuel tank 68 are supported by the seat rail 62, and the rear portion of the fuel tank 68 is supported by a cross member 82 extending between the right and left rear frames 61, thereby protecting both the tanks 67 and 68. The seat 16 is composed of a bottom plate 91, a cushion member 92, and a skin 93. The seat 16 is vertically pivotably supported through a seat hinge 95 to a bracket 94 provided at the front end of the seat rail 62. A U-shaped striker 96 is fixed to the lower surface of the bottom plate 91, and a lock mechanism 97 engageable with the striker 96 is provided on the rear portion of the tray 74. The lock mechanism 97 is linked through a Bowden wire 99 to a cylinder lock 98 provided at the rear end of the tray 74, thereby restricting the opening and closing of the seat 16 due to mischief. A closed antitheft tool 100 is stored in the space defined between the upper surface of the tray 74 and the lower surface of the bottom plate 91 of the seat 16. The antitheft tool 100 is composed of a U-shaped body portion 101 and a rodlike detachable portion 102 lockable to both ends of the body portion 101 by key operation. For example, the body portion 101 is passed through any one openings of the wheel 44 of the rear wheel Wr, and in this condition the detachable portion 102 is locked to the body portion 101. Alternatively, the body portion 101 is passed through any one openings of the wheel 44 of the rear wheel Wr and is engaged with a fixed structure such as a guide rail post, and in this condition the detachable portion 102 is locked to the body portion 101. Thus, a theft of the motorcycle V can be prevented. As apparent from FIG. 7, the cap 75 of the oil tank 67, the cap 81 of the fuel tank 68, the projection 74 2 within which the fuel level sensor 80 of the fuel tank 68 is fitted, and the lock mechanism 97 project upward from the upper surface of the tray 74. The antitheft tool 100 is placed on the upper surface of the tray 74 so that the cap 81, the projection 74 2 , and the lock mechanism 97 are disposed in the space surrounded by the body portion 101 and the detachable portion 102 of the antitheft tool 100. As mentioned above, there is necessarily defined the space between the upper surface of the tray 74 and the bottom plate 91 of the seat 16 because of the presence of various projecting objects including the cap 75 of the oil tank 67, the cap 81 of the fuel tank 68, the projection 74 2 within which the fuel level sensor 80 of the fuel tank 68 is fitted, and the lock mechanism 97. This space can be effectively used as a space for storing the antitheft tool 100. Furthermore, since the cap 81, the fuel level sensor 80, and the lock mechanism 97 are arranged in the longitudinal direction of the vehicle body, and the closed antitheft tool 100 is disposed so as to surround these projecting objects, various antitheft tools different in length and width as the antitheft tool 100 can be stored in the above space. A lock lever supporting member 103 is provided on the lower surface of the bracket 61 4 supporting the rear portion of the fuel tank 68, and a stand lock lever 105 is horizontally pivotably supported through a pivot 104 to the lock lever supporting member 103. On the other hand, the main stand 18 is vertically swingably supported through a pin 107 to a stand stay 106 provided at the lower portion of the vehicle frame F. The main stand 18 is designed to stably hold either a standing position shown in FIG. 8 or a retracted position obtained by rearward and upward swing from the standing position, by the elastic force of a toggle spring 108. A cam plate 110 is horizontally pivotably supported through a pivot 109 to the stand stay 106. The cam plate 110 is linked through a Bowden wire 111 to the stand lock lever 105, and is biased counterclockwise as viewed in FIG. 8 by a spring 112. A stopper plate 113 integral with the main stand 18 is formed with a slit 113 1 with which the cam plate 110 is engageable. Accordingly, when the stand lock lever 105 is operated from a phantom line position to a solid line position shown in FIG. 8 in the standing condition of the main stand 18, the cam plate 110 is pulled by the Bowden wire 111 to rotate clockwise about the pivot 109 against the spring 112 and come into engagement with the slit 113 1 of the stopper plate 113 integral with the main stand 18, thereby locking the main stand 18 in the standing position. As apparent from FIG. 7, the stand lock lever 105 is disposed below the detachable portion 102 of the antitheft tool 100. Accordingly, when the seat 16 is opened to take out the antitheft tool 100 in the rest condition of the motorcycle V, the stand lock lever 105 having been disposed below the antitheft tool 100 naturally comes into rider's view, thereby eliminating the possibility that the rider may forget about locking the main stand 18. Having thus described the specific embodiment of the present invention, it should be noted that various design modifications may be made without departing from the scope of the present invention as defined by the claims. For example, although both the oil tank 67 and the fuel tank 68 are disposed in the space surrounded by the rear frames 61 and the seat rail 62 in the above preferred embodiment, only one of the oil tank 67 and the fuel tank 68 may be disposed in this space. The present invention seeks to ensure the detachability of a tank disposed below a seat and increase the capacity of the tank. A seat frame 62 is detachably fixed by bolts 65 and 66 to the upper portion of a rear frame 61, and a seat 16 is supported to the upper portion of the seat rail 62. An oil tank 67 and a fuel tank 68 are disposed in the space surrounded by the rear frame 61 and the seat rail 62. A projection 68 3 is formed on each side surface of the fuel tank 68 so as to project between the rear frame 61 and the seat rail 62, thereby increasing the capacity of the fuel tank 68. When the seat rail 62 is removed from the rear frame 61, the tanks 67 and 68 can be mounted and removed without interference with the seat rail 62.

Claims: A scooter type vehicle comprising a seat rail (62) provided on an upper portion of a frame (61) to support a seat (16), and a tank (67, 68) formed of synthetic resin and located in a space surrounded by said frame (61) and said seat rail (62) the vehicle being characterized in that said seat rail (62) is detachable from said frame (61). A scooter type vehicle according to claim 1, characterised in that said seat rail (62) is formed in a U-shape as viewed in plan so as to cover a front surface and right and left side surfaces of said tank (67, 68). A scooter type vehicle according to claim 1, characterised in that a projection (68 3 ) is formed on each side surface of said tank (68) so as to project between said frame (61) and said seat rail (62) both extending along each side surface of said tank (68).

Inventors: SAKO HIROYUKI, SUZUKI MASAAKI, SAKO, HIROYUKI, SUZUKI, MASAAKI, Sako, Hiroyuki, K.K. Honda Gijutsu Kenkyusho, Suzuki, Masaaki, K.K. Honda Gijutsu Kenkyusho
Applicants: HONDA MOTOR CO LTD, HONDA GIKEN KOGYO KABUSHIKI KAISHA
Application year: 1996
Main classification: B62K11
IPC codes: B62J35, F02B61, B62J1, B62H5, B62K11, B62M7