Fuel battery mounted motorcycle

Abstract: The invention provides a fuel battery mounted motorcycle (10) intended to lower the center of gravity of the motorcycle (10) by disposing a reformer (32) for generating hydrogen, together with a fuel battery (33) and a secondary battery (36), in a lower portion of a floor (27). The center of gravity of the motorcycle (10) can be lowered and the floor (27) can be effectively utilized for the purpose other than the original purpose of the floor (27).

Description: The present invention relates to a motorcycle with a fuel battery mounted thereon. A fuel battery mounted vehicle including a low level floor, wherein the battery is disposed in a lower portion of said floor is known from JP-A-05 260611. Fuel battery mounted motorcycles are known, for example, from Japanese Patent Laid-open No. Hei 3-109126 entitled "Fuel Battery Mounted Motorcycle". As shown in FIG. 1 of the above document, the above technique discloses an electric motorcar 1 using a fuel battery 13 as an energy source, wherein the fuel battery 13 is disposed in a lower central portion of a vehicular body 2 (note: reference numerals are cited from the document). In the case of using the fuel battery 13 as an energy source, as will be described later, the motorcycle 1 must be provided with, in addition to the fuel battery 13, a fuel tank for storing methanol, a reformer for generating hydrogen, a secondary battery for storing an electric power generated by the fuel battery 13, and the like. Further, in the case of mounting a fuel battery like the fuel battery 13 on a motorcycle, the layout of the fuel battery, reformer, secondary battery, and the like becomes important. The principle of power generation by a fuel battery and one example of a fuel battery system will be hereinafter described. FIGS. 15(a) and 15(b) are diagrams illustrating the principle of power generation by a fuel battery, wherein FIG. 15(a) shows the principle of electrolysis of water, and FIG. 15(b) shows the principle of power generation by the fuel battery. Referring to FIG. 15(a), the electrolytic process of water (H 2 O) is performed by filling a water tank 101 with water (H 2 O) in which an electrolyte such as sulfuric acid (H 2 SO 4 ) has been dissolved; setting electrodes 102 and 103, each of which is typically made from platinum, in the water tank 101; covering the electrodes 102 and 103 with containers 104 and 105, respectively; and applying a current, from a DC power source 106, between the electrodes 102 and 103, whereby oxygen gas (O 2 ) is generated on the electrode 102 side taken as the plus side and hydrogen gas (H 2 ) is generated on the electrode 103 side taken as the minus side. In the figure, an arrow (e - ) designates the flow of electrons and an arrow (H + ) designates the flow of hydrogen ions. Referring to FIG. 15(b), the power generation process is performed in accordance with steps reversed to those shown in FIG. 15(a), that is, by filling the container 104 with oxygen gas (O 2 ) and the container 105 with hydrogen gas (H 2 ); connecting a load 107 between the electrodes 102 and 103; and making the oxygen gas (O 2 ) and hydrogen gas (H 2 ) electrochemically react with each other in water (H 2 O) in which sulfuric acid (H 2 SO 4 ) as an electrolyte has been dissolved, whereby a current flows in the load 107, and the oxygen gas (O 2 ) is bonded to the hydrogen gas (H 2 ) to produce water (H 2 O). In this way, as shown in FIG. 5(b), the process of power generation of a fuel battery is reversed to the process of electrolysis of water shown in FIG. 5(a). The fuel battery system will be described with reference to FIG. 16. FIG. 16 is a block diagram showing one example of the fuel battery system. A fuel battery system 110 includes a fuel tank 111 for storing methanol; a reformer 112 for generating hydrogen from methanol and water; a fuel battery 113 for making hydrogen generated by the reformer 112 electrochemically react with oxygen in air; a first pump 115 for supplying outside air to the fuel battery 113 via an air cleaner 114; a second pump 116 for supplying hydrogen from the reformer 112 to the fuel battery 113; a catalyzer 117 for receiving water vapor from the fuel battery 113 and carbon dioxide gas from the reformer 112 via the fuel battery 113 and for reducing the amount of carbon dioxide gas; a water tank 118 for receiving water from the catalyzer 117; a secondary battery 119 for storing an electric power generated by the fuel battery 113; and a motor 122 connected to the secondary battery 119 via a control unit 121. In addition, the secondary battery 119 also functions to store an electric power generated by the motor 122. In the figure, a hollow arrow (CH 3 OH) designates the flow of methanol; a hollow arrow (H 2 ) is the flow of hydrogen gas; a hollow arrow (O 2 ) is the flow of oxygen gas; a hollow arrow (H 2 O + CO 2 ) is the flow of water vapor and carbon dioxide gas; and a hollow arrow (H 2 O) is the flow of water. As described above, in the case of using the fuel battery 113 as an energy source of a motorcycle (not shown), it is required to provide, in addition to the fuel battery 113, the fuel tank 111 for storing methanol, the reformer 112 for generating hydrogen, the secondary battery 119 for storing an electric power generated by the fuel battery 113, and the like; and in the case of actually mounting these fuel battery 113, fuel tank 111, reformer 112, and the like on a motorcycle, it is required to examine the layout of the fuel battery system 110 including the fuel battery 113, fuel tank 111, reformer 112, and the like from the viewpoint of various factors such as the weight balance, maintenance, and design. An object of the present invention is to provide a technique of mounting a fuel battery on a motorcycle, which is capable of optimally arranging the fuel battery, a secondary battery, and the like. This object is achieved by a motorcycle comprising a fuel battery according to claim 1. A fuel battery mounted motorcycle includes a low level floor, wherein at least one of a fuel battery and a reformer for generating hydrogen is disposed in a lower portion of the floor. With this configuration, since at least one of the fuel battery and the reformer for generating hydrogen is disposed in a lower portion of the floor, it is possible to lower the center of gravity of the motorcycle. The reformer for generating hydrogen can be disposed, together with the fuel battery, in a lower portion of the floor. With this configuration, since the reformer for generating hydrogen is disposed, together with the fuel battery, in the lower portion of the floor, it is possible to further lower the center of gravity of the motorcycle, and also to shorten pipes for connecting the fuel battery to the reformer. Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a side view of a comparative fuel battery mounted motorcycle. FIG. 2 is a plan diagram showing the layout of a fuel battery system of the comparative fuel battery mounted motorcycle. FIG. 3 is a diagram illustrating the operation of the fuel battery system of the comparative fuel battery mounted motorcycle. FIG. 4 is a plan diagram showing the layout of a first modification of the fuel battery system of the comparative fuel battery mounted motorcycle. FIG. 5 is a plan diagram showing the layout of a second modification of the fuel battery system of the comparative fuel battery mounted motorcycle. FIG. 6 is a front diagram showing the layout of a third modification of the fuel battery system of the comparative fuel battery mounted motorcycle. FIG. 7 is a front diagram showing the layout of a fourth modification of the fuel battery system of the comparative fuel battery mounted motorcycle. FIG. 8 is front diagram showing the layout of a fifth modification of the fuel battery system of the comparative fuel battery mounted motorcycle. FIG. 9 is a side view of a further embodiment of the comparative fuel battery mounted motorcycle. FIG. 10 is a side view of a further embodiment of the comparative fuel battery mounted motorcycle. FIG. 11 is a side view of a first embodiment of the fuel battery mounted motorcycle according to the present invention. FIG. 12 is a side view of a second embodiment of the fuel battery mounted motorcycle according to the present invention. FIG. 13 is a side view of a further embodiment of the comparative fuel battery mounted motorcycle. FIG. 14 is a side view of a further embodiment of the comparative fuel battery mounted motorcycle. FIGS. 15(a) and 15(b) are diagrams illustrating the power generation principle of a fuel battery. FIG. 16 is a block diagram showing one example of a fuel battery system. In the drawings, the "front", "rear", "left", "right", "upper", "lower" sides are based on the line of view of the driver riding on a motorcycle to which the present invention is applied, and characters "Fr", "Rr", L", and "R" designate the front, rear, left, and right sides, respectively. Additionally, the drawings should be viewed in the direction of characters. FIG. 1 is a side view of a first embodiment of a comparative fuel battery mounted motorcycle. Referring to this figure, there is shown a fuel battery mounted motorcycle 10 (hereinafter, referred to simply as "motorcycle 10"), which is configured, according to this embodiment, as a scooter-type motorcycle including a low level floor. The motorcycle 10 mainly includes a front fork 13 mounted to a head pipe 12 of a body frame 11; a front wheel 14 mounted to the front fork 13; a handlebar 15 connected to the front fork 13; a swing unit 16 mounted to an upper rear portion of the body frame 11; a rear wheel 17 mounted to a rear portion of the swing unit 16: a seat 18 disposed on an upper rear portion of the body frame 11; a fuel battery system 30 with its main portion disposed under the body frame 11; and a power unit 45 driven by the fuel battery system 30. In the figure, reference numeral 19 designates a helmet box, and 21 is a rear suspension. The body frame 11 includes a down tube 22 extending rearwardly from the head pipe 12, and a center tube 23 extending rearwardly from the down tube 22. A pair of right and left rear pipes 24 (only one is shown in the figure) extend from a mid point of the center tube 23. A front stay 25 extends downwardly from a mid point of the down tube 22 and a rear stay 26 extends downwardly from the rear end of the center tube 23. A low level type floor 27 is provided in such a manner as to connect the lower ends of the front and rear stays 25 and 26 to each other. FIG. 2 is a plan diagram showing the layout of the fuel battery system of the comparative fuel battery mounted motorcycle. The fuel battery system 30 includes a fuel tank 31 for storing methanol; a reformer 32 for generating hydrogen from methanol supplied from the fuel tank 31 and water; a fuel battery 33 for making hydrogen generated by the reformer 32 electrochemically react with oxygen in air; a catalyzer 34 for receiving water from the fuel battery 33 and carbon dioxide from the reformer 32 via the fuel battery 33 and reducing the amount of carbon dioxide; a water tank 35 for receiving water from the catalyzer 34; and a plurality of secondary batteries 36 for storing an electric power generated by the fuel battery 33 and also storing an electric power generated by the power unit 45. In the figure, character C designates the center plane of a vehicular body of the motorcycle 10. The fuel battery 33 includes a radiator 38 for cooling the fuel battery 33; a first pump 39 for supplying hydrogen from the reformer 32 to the fuel battery 33; and a second pump 42 for supplying oxygen in air to the fuel battery 33 via an air cleaner 41. The water tank 35 includes an exhaust pipe 43 for discharging water vapor. The power unit 45 includes a motor 46 driven by the secondary batteries 36 and the fuel battery 33; a belt-type automatic transmission 47 connected to the motor 46; and a control unit 48 for controlling these belt-type automatic transmission 47 and the motor 46. In the figure, reference numeral 47a designates a case of the belt-type automatic transmission 47. As shown in FIG. 2, the motorcycle 10 including the low level floor 27 is configured such that at least one of the fuel battery 33 and the reformer 32 is disposed in a lower portion of the floor 27. As a result, the center of gravity of the motorcycle 10 can be lowered and the floor 27 is effectively utilized for the purpose other than the original purpose of the floor 27. The motorcycle 10 is also configured such that the reformer 32 for generating hydrogen is disposed, together with the fuel battery 33, in a lower portion of the floor 27. As a result, the center of gravity of the motorcycle 10 can be further lowered and pipes used for connecting the reformer 32 to the fuel battery 33 can be shortened. The motorcycle 10 is further configured such that the secondary batteries 36 are disposed, together with the fuel battery 33, in a lower portion of the floor 27. As a result, the center of gravity of the motorcycle 10 can be lowered. That is to say, since the heavy secondary batteries 36 and fuel battery 33 are disposed in the lower portion of the floor 27, the center of gravity of the motorcycle 10 can be further lowered. The motorcycle 10 is further configured such that the reformer 32 for generating hydrogen is disposed, together with the fuel battery 33 and the secondary batteries 36, in a lower portion of the floor 27. As a result, the center of gravity of the motorcycle 10 can be further lowered and the floor 27 can be effectively utilized for the purpose other than the original purpose of the floor 27. Further, the system using the reformer 32, fuel battery 33, and secondary batteries 36 can be centralized, and wires or pipes for electrically or fluidly connecting the reformer 32, fuel battery 33, and secondary batteries 36 to each other can be shortened. As shown in FIG. 2, the motorcycle 10 including the fuel battery 33, secondary batteries 36, motor 46, and belt-type automatic transmission 47 according to this embodiment is configured such that the belt-type automatic transmission 47 is disposed on one side with respect to the center plane C of the vehicular body and the secondary batteries 36 is disposed on the other side with respect to the center plane C of the vehicular body. As a result, the weights on the right and left sides of the motorcycle 10 can be kept in balance The operation of the above-described fuel battery system 30 will be described below. FIG. 3 is a diagram illustrating the operation of the fuel battery system of the comparative fuel battery mounted motorcycle. In this figure, methanol, oxygen, hydrogen, and water flow in respective directions shown by arrows (1) to (6). In the fuel battery system 30, methanol is supplied from the fuel tank 31 to the reformer 32 as shown by the arrow (1) and water is supplied from the water tank 35 to the reformer 32 as shown by the arrow (2), and hydrogen produced by the reforming in the reformer 32 is supplied to the fuel battery 33 along the direction arrow (3) and oxygen in air is supplied to the fuel battery 33 via the air cleaner 41 as shown by the arrow (4) by the second pump 42, to generate an electric power in the fuel battery 33. Water vapor and carbon dioxide are discharged from the fuel battery 33 to the catalyzer 34 as shown by the arrow (5) to reduce the amount of carbon dioxide, and part of water vapor is discharged to atmospheric air from the exhaust pipe 43 as shown by the arrow (6) and the residue of water vapor is stored in the water tank 35 to be circulated to the reformer 32 as described. FIG. 4 is a plan diagram showing the layout of a first modification of the fuel battery system of the comparative fuel battery mounted motorcycle. In this figure showing a fuel battery system 51, for the sake of clarity, parts corresponding to those of the above-described fuel battery system 30 are designated by the same reference numerals. That is to say, reference numeral 27 designates a floor; 32 is a reformer; 33 is a fuel battery; 34 is a catalyzer; 35 is a water tank; 36 is a secondary battery; 38 is a radiator; 39 is a first pump; 41 is an air cleaner; 42 is a second pump; and 43 is an exhaust pipe. As shown in this figure, the fuel battery system 51 is configured such that the heavy secondary battery 36 is disposed on the front side of a lower portion of the floor 27. In the motorcycle 10 (see FIG. 1) having the above-described fuel system 51, since the secondary battery 36 is disposed on the front side of the lower portion of the floor 27 and the fuel battery 33 is disposed on the rear side of the lower portion of the floor 27, it is possible to easily perform the maintenance of the secondary battery 36, and to increase a load distributed on the front wheel 14 (see FIG. 1) of the motorcycle 10 and thereby keep the weight of the front wheel 14 in balance against the weight of the rear wheel 17. FIG. 5 is a plan diagram showing the layout of a second modification of the fuel battery system of the comparative fuel battery mounted motorcycle. In this figure showing a fuel battery system 52, for the sake of clarity, parts corresponding to those of the above-described fuel battery system 30 are designated by the same reference numerals. That is to say, reference numeral 27 designates a floor; 32 is a reformer; 33 is a fuel battery; 34 is a catalyzer; 35 is a water tank; 36 is a secondary battery; 38 is a radiator; 39 is a first pump; 41 is an air cleaner; 42 is a second pump; and 43 is an exhaust pipe. As shown in this figure, the fuel battery system 52 is configured such that the heavy secondary battery 36 is disposed on the rear side of a lower portion of the floor 27. As a result, it is possible to improve the effect of cooling the reformer 32 and the fuel battery 33. FIG. 6 is a front diagram showing the layout of a third modification of the fuel battery system of the comparative fuel battery mounted motorcycle. In this figure showing a fuel battery system 53, for the sake of clarity, parts corresponding to those of the above-described fuel battery system 30 are designated by the same reference numerals. That is to say, reference numeral 27 designates a floor; 32 is a reformer; 33 is a fuel battery; and 36 is a secondary battery. As shown in this figure, the fuel battery system 53 is configured such that the fuel battery 33 and the reformer 32 are disposed in a lower portion of the floor 27 and the secondary battery 36 is disposed on these fuel battery 33 and the reformer 32. In the motorcycle 10 (see FIG. 1) including the above fuel system 53, since the secondary battery 36 and the fuel battery 33 are stacked to each other in the vertical direction, it is possible to easily change the capacity of the secondary battery 36. FIG. 7 is a front diagram showing the layout of a fourth modification of the fuel battery system of the comparative fuel battery mounted motorcycle. In this figure showing a fuel battery system 54, for the sake of clarity, parts corresponding to those of the above-described fuel battery system 30 are designated by the same reference numerals. That is to say, reference numeral 27 designates a floor; 32 is a reformer; 33 is a fuel battery; and 36 is a secondary battery. As shown in this figure, the fuel battery system 54 is configured such that the secondary battery 36 is disposed in a lower portion of the floor 27 and the fuel battery 33 and the reformer 32 are disposed on the secondary battery 36. In the motorcycle 10 (see FIG. 1) including the fuel system 54, since the secondary battery 36 and the fuel battery 33 are stacked to each other in the vertical direction, it is possible to lower the center of gravity of the motorcycle 10 by disposing the secondary battery 36 under the fuel battery 33. FIG. 8 is front diagram showing the layout of a fifth modification of the fuel-battery system of the comparative fuel battery mounted motorcycle. In this figure showing a fuel battery system 55, for the sake of clarity, parts corresponding to those of the above-described fuel battery system 30 are designated by the same reference numerals. That is to say, reference numeral 27 designates a floor; 32 is a reformer; 33 is a fuel battery; and 36 is a secondary battery. As shown in this figure, the fuel battery system 55 is configured such that the fuel battery 33 is disposed in a lower portion of the floor 27, and the secondary battery 36 and the reformer 32 are disposed on the fuel battery 33 in such a manner as to be located on the front and rear sides, respectively. As a result, it is possible to easily perform the maintenance of the secondary battery 36 and the reformer 32. FIG. 9 is a side view of a further embodiment of the comparative fuel battery mounted motorcycle. In this figure, reference numeral 61 designates a body frame; 62 is a front frame made from aluminum by die-casting, which constitutes part of the body frame 61; 63 is a rear frame made from aluminum by die-casting, which constitutes part of the body frame 61; 64 is a front suspension; 65 is a handlebar; 66 is a swing unit; 67 is a rear suspension; 68 is a seat; 69 is a helmet box; 71 is a front wheel; 72 is a rear wheel; and 73 is a drive unit composed of a transmission and a motor. As shown in this figure, a fuel battery mounted motorcycle 60 (hereinafter, referred to as "motorcycle 60") is configured such that a power generation unit 76 mainly including a fuel battery, a reformer, and a secondary battery is mounted in a lower portion of a floor 62a of the die-cast front frame 62, and a fuel tank 77 for storing methanol is mounted to the die-cast rear frame 63. In the motorcycle 60, the body frame 62 is divided into the die-cast front frame 62 and the die cast rear frame 63, and the respective components are mounted to the frames 62 and 63. As a result, it is possible to easily assemble the motorcycle 60 and hence to reduce the assembling cost. FIG. 10 is a side view of a further embodiment of the fuel battery mounted motorcycle. A fuel battery mounted motorcycle 83 (hereinafter, referred to as "motorcycle 83") is configured such that a plurality of secondary batteries 83c are disposed in a lower portion of a floor 83b of a body frame 83a, and a fuel battery 83e, a reformer 83f for generating hydrogen, and a fuel tank 83g for storing methanol are disposed on the secondary batteries 83c in this order from the front side. In this figure, reference numeral 83h designates a radiator provided on the fuel battery 83e; 83i is a seat; and 83j is a helmet box. With this configuration, since the secondary batteries 83c and the fuel battery 83e are disposed in the lower portion of the floor 83b of the body frame 83a, it is possible to lower the center of gravity of the motorcycle 83. Fig. 11 is a side view of a first embodiment of the fuel battery mounted motorcycle according to the present invention. A fuel battery mounted motorcycle 84 (hereinafter, referred to as "motorcycle 84") is configured such that a fuel battery 84e, a reformer 84f, and a fuel tank 84g are disposed in a lower portion of the floor 84b of a body frame 84a, and a plurality of secondary batteries 84c are disposed on a rear portion of the body frame 84a. In this figure, reference numeral 84h designates a radiator provided on the fuel battery 84e; 84i is a seat; and 84j is a helmet box. With this configuration, since the secondary batteries 84c are disposed on the rear portion of the body frame 84a, it is possible to enlarge an inner space of the floor 84b of the motorcycle 84. FIG. 12 is a side view of a second embodiment of the fuel battery mounted motorcycle according to the present invention. A fuel battery mounted motorcycle 85 (hereinafter, referred to as "motorcycle 85") is configured such that a fuel battery 85e, a reformer 85f, and an L-shaped fuel tank 85g are disposed in a lower portion of a floor 85b of a body frame 85a, and a plurality of secondary batteries 85c are disposed on a rear portion of the body frame 85a. In this figure, reference numeral 85h designates a radiator provided on the fuel battery 85e; 85i is a seat; and 85j is a helmet box. In addition, the motorcycle 85 is intended to directly drive a rear wheel 85k by a motor 85n with a transmission. With this configuration, since the L-shaped fuel tank 85g is disposed in the lower portion of the floor 85b of the body frame 85a, it is possible to easily supply fuel to the motorcycle 85. FIG. 13 is a side view of a further embodiment of the comparative fuel battery mounted motorcycle. A fuel battery mounted motorcycle 86 (hereinafter, referred to as "motorcycle 86") is configured such that a fuel battery 86e is disposed under a front portion of a seat 86i, and secondary batteries 86c and 86d, a fuel tank 86g for storing methanol, and a reformer 86f for generating hydrogen are disposed in a lower portion of a floor 86b of a body frame 86a. This layout is suitable for a large-sized scooter type motorcycle. In the figure, reference numeral 86j designates a helmet box. According to the motorcycle 86, since the fuel battery 86e is disposed under the front portion of the seat 86i, it is possible to enlarge an inner space of the floor 86b. FIG. 14 is a side view of a further embodiment of.the comparative fuel battery mounted motorcycle. In this figure, reference numeral 87a designates a body frame; 87b is a floor; 87c and 87d are secondary batteries, 87g is a fuel tank; 87f is a reformer, and 87j is a helmet box. A fuel battery mounted motorcycle 87 (hereinafter, referred to as "motorcycle 87") is configured such that the fuel battery 87e is disposed under a rear portion of the seat 87i. According to the motorcycle 87, since the fuel battery 87e is disposed under the rear portion of the seat 87i, it is possible to enlarge an inner space of the floor 87b. According to the first comparative embodiment, the fuel tank 31 is provided on the body frame 11 as shown in FIG. 1; however, this embodiment is not limited thereto. For example, the fuel tank 31 may be provided, together with the fuel battery 33, reformer 32, and secondary batteries 36 (see FIG. 2), in the lower portion of the floor 27. Further, according to the first comparative embodiment, the secondary battery 36 is disposed on the front side and the reformer 32 is disposed on the rear side; however, this embodiment is not limited thereto but may be configured such that the secondary battery 36 be disposed on the rear side and the reformer 32 is disposed on the front side.

Claims: A motorcycle with a fuel battery mounted thereon, said motorcycle including a body frame (84a) with a low level floor (84b), wherein said fuel battery (84e) is disposed in a lower portion of said floor (84b) as an energy source, characterized in that the body frame (84a) is provided with a rear portion for supporting a seat (84i) and in that a secondary battery (84c) is disposed on said rear portion of said body frame (84a). The motorcycle according to claim 1, wherein said motorcycle includes a helmet box (84j) disposed, together with said secondary battery (84c), under said seat (84i).

Inventors: HIRAYAMA SHUUJI, IGARASHI MASASHI, ISENO MITSURU, TORIYAMA MASAYUKI, YAMASHITA NOBORU, HIRAYAMA, SHUUJI, IGARASHI, MASASHI, ISENO, MITSURU, TORIYAMA, MASAYUKI, YAMASHITA, NOBORU, Hirayama, Shuuji, K.K. Honda Gijutsu Kenkyusho, Igarashi, Masashi, K.K. Honda Gijutsu Kenkyusho, ISENO, MITSURU, K.K. HONDA GIJUTSU KENKYUSHO, Toriyama, Masayuki, K.K. Honda Gijutsu Kenkyusho, Yamashita, Noboru, K.K. Honda Gijutsu Kenkyusho
Applicants: HONDA MOTOR CO LTD, HONDA GIKEN KOGYO KABUSHIKI KAISHA
Application year: 2001
Main classification: B60L11
IPC codes: B62J9, B60K8, B60L11, H01M8, B62K11, B62J11, B62M7