Electric vehicles

Abstract

To provide an electric vehicle capable of charging a sub-battery while the vehicle is running, and switching from the main battery to the sub-battery when the main battery becomes low, thereby continuing the running. [Solution] The electric vehicle of the present invention comprises a drive motor that rotates the drive wheels, a generator motor that generates electricity through the rotation of the driven wheels, a main battery that supplies power to the drive motor, a sub-battery that can store the power generated by the generator motor, a battery status detection unit that measures the remaining power of the main battery and the sub-battery, a change-over switch that switches the power supply to the drive motor between the main battery and the sub-battery, and a cut-off switch that cuts off charging to the sub-battery.When the power of the main battery falls below a threshold value due to the vehicle being driven, the cut-off switch cuts off charging to the sub-battery and the change-over switch switches from the main battery to the sub-battery.

Description

[Technical Field]

[0001] The present invention relates to an electric vehicle, and more particularly to an electric vehicle that has a power generating motor on the front wheels to exclusively charge a sub-battery, and when the storage capacity of the main battery becomes low, switches to the sub-battery to continue traveling. [Background technology]

[0002] Patent Document 1 shows a structure in which power packs 120A and 120B are provided to drive the vehicle's motor, and when the remaining capacity of one power pack decreases, the power pack is switched to the other power pack to extend the driving distance. However, Patent Document 1 does not mention charging the power packs 120A and 120B while the vehicle is running.

[0003] Patent Document 2 shows a structure in which multiple batteries are provided to supply power to a motor that drives the rear wheels, and when the motor is ready to supply regenerative power, the regenerative power is supplied to the battery with the least remaining charge among the multiple batteries to charge it. This control is excellent in terms of recovering regenerative power, but it is complicated to detect the conditions for recovering regenerative power when there is no need to drive the rear wheels by the motor and to switch the power supply path. Furthermore, it does not show how the rotational energy of the wheels is converted into electrical energy and stored. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-359032 [Patent Document 2] Japanese Patent Publication No. 2022-149725 Summary of the Invention [Problem to be solved by the invention]

[0005] To provide an electric vehicle that converts the rotational energy of wheels into electricity and stores it in a sub-battery while the vehicle is running, and when the main battery that drives the wheels becomes low, switches from the main battery to the sub-battery to run the vehicle. [Means for solving the problem]

[0006] The electric vehicle according to the present invention is an electric vehicle in which one of the front wheels and the rear wheels is a drive wheel and the other is a driven wheel, and is equipped with a drive motor that rotates the drive wheels, a generator motor that generates electricity through the rotation of the driven wheels, a main battery that supplies power to the drive motor, a sub-battery that can store the electricity generated by the generator motor, battery status detection units that are provided in the main battery and the sub-battery and measure the remaining charge, a change-over switch that switches the power supply to the drive motor between the main battery and the sub-battery, and a cut-off switch that cuts off charging from the generator motor to the sub-battery, and is characterized in that when the power of the main battery falls below a threshold value due to the vehicle being driven, the cut-off switch cuts off charging to the sub-battery and the change-over switch switches from the main battery to the sub-battery.

[0007] In addition, the present invention is characterized in that a large-diameter drive wheel is attached to the driven wheel so as to rotate coaxially, a small-diameter driven wheel is attached to the rotating shaft of the generator motor, and the drive wheel and the driven wheel are connected by a transmission belt.

[0008] Furthermore, the main battery and the sub-battery can be charged externally via charging terminals. [Effects of the Invention]

[0009] The electric vehicle of the present invention is equipped with two batteries: a main battery and a sub-battery. The generator motor converts the rotational energy of the wheels into electrical energy that is stored in the sub-battery. Therefore, when the remaining charge in the main battery becomes low, the sub-battery can be used to supply power to the drive motor, allowing the vehicle to continue running.

[0010] A large diameter wheel is attached to the driven wheel so that they rotate coaxially, and a small diameter wheel is attached to the rotating shaft of the generator motor, and the two are connected by a transmission belt, so the rotor of the generator motor can rotate at a higher rotation speed (rpm) than the rotation speed (rpm) of the driven wheel, which allows for the generation of large amounts of electricity.

[0011] The main battery and sub-battery can be charged externally via the charging terminals, so for example, (1) if the main battery becomes empty, the vehicle can be driven again by charging it externally. (2) The sub-battery can also be charged and driven. This ensures a driving distance equal to the combined electric capacity of the main battery and sub-battery. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a structural diagram of an electric vehicle according to the present invention; [Figure 2] FIG. 2 is a block diagram showing the battery configuration of the electric vehicle. [Figure 3] This is a diagram showing that a large diameter drive wheel provided on the front wheel and a small diameter driven wheel provided on the generator motor are connected by a belt. [Figure 4] FIG. 2 is a diagram illustrating the relationship between a battery and a drive motor while the vehicle is running. [Figure 5] 10 is a flowchart showing switching between the main battery and the sub-battery while the vehicle is running. [Figure 6] FIG. 10 is an explanatory diagram showing how the main battery and the sub-battery 7 are charged by an external charger. [Figure 7]This is an explanatory diagram showing how the vehicle alternates between driving the drive motor with the main battery and charging the sub-battery with the generator motor, and driving the drive motor with the sub-battery and charging the main battery with the generator motor. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of an electric vehicle 100 according to the present invention will be described with reference to the drawings.

[0014] FIG. 1 is a structural diagram of an electric vehicle 100 according to the present invention. The electric vehicle 100 of this embodiment is an electric two-wheeler. However, the present invention is not limited to this, and can also be applied to electric tricycles, power-assisted bicycles with pedals, and the like. The electric vehicle 100 is equipped with a main body 3, a front wheel 1 that is rotated by a handlebar, and a rear wheel 2 that is driven by a three-phase AC drive motor 5. A three-phase AC generator motor 4 is attached to the front wheel 1. Electric power generated by the generator motor 4 is stored in the sub-battery 7 when the sub-battery 7 is not fully charged. The drive motor 5 rotates by receiving power from the main battery 6 or the sub-battery 7. A warning lamp 22 that indicates when the power of the main battery 6 drops below a threshold, and a warning lamp 23 that indicates when the power of the sub-battery 7 drops below a threshold, are provided above the handlebars.

[0015] 2 is a block diagram showing the battery configuration of the electric vehicle 100. The battery consists of a main battery 6 and a sub-battery 7. The main battery 6, drive motor 5, and rear wheels 2 form the drive system, while the sub-battery 7, generator motor 4, and front wheels 1 form the driven system, and a switching system is provided to switch between the main battery 6 and the sub-battery 7. In this configuration, the rear wheels 2 are drive wheels, and the front wheels 1 are driven wheels.

[0016] When the electric vehicle 100 is driven by power from the main battery 6, power is supplied from the main battery 6 to the drive motor 5 via the selector switch 13, causing the drive motor 5 to rotate, and the rotation is transmitted to the rear wheels 2. When the rear wheels 2 rotate, the front wheels 1, which are driven wheels, rotate, causing the electric vehicle 100 to move. The main battery 6 has a charging terminal and is a battery that can be charged externally.

[0017] The sub-battery 7 is charged by the generator motor 4, which generates electricity through the rotation of the front wheels 1. Because the generator motor 4 is a three-phase AC motor, the AC is converted to DC by a converter 17 and sent to the sub-battery 7 via the cut-off switch 12. When the sub-battery 7 is fully charged, the cut-off switch 12 is cut off by the switching control unit 8, and charging is stopped. The sub-battery 7 is provided with a sub-battery state detection unit 14B that detects the state of charge (measures voltage to determine whether there is power), and the state of the sub-battery 7 is sent to the switching control unit 8 via a detection signal. Like the main battery 6, the sub-battery 7 also has a charging terminal and can be charged externally.

[0018] The changeover switch 13 switches between the main battery 6 and the sub-battery 7 as the power source for supplying power to the drive motor 5. The main battery 6 is provided with a main battery state detection unit 14A that detects the charge state, and the state of the main battery 6 is sent to the switching control unit 8 via an output signal from the main battery state detection unit 14A. For example, if the power of the main battery 6 falls below a threshold value, the switching control unit 8 switches the changeover switch 13 from the main battery 6 to the sub-battery 7.

[0019] FIG. 3 shows that a large-diameter drive wheel 9 attached to the front wheel 1 and a small-diameter driven wheel 10 attached to the generator motor 4 are connected by a belt 16. The drive wheel 9 is attached to the shaft 15 of the front wheel 1, and the driven wheel 10 is attached to the rotating shaft 11 of the generator motor 4. With this configuration, because the small-diameter driven wheel 10 is connected to the large-diameter drive wheel 9, the number of rotations per unit time of the rotor of the generator motor 4 can be made larger than the number of rotations of the front wheel 1, allowing for large amounts of power to be generated. When going downhill, the front wheel 1 rotates at high speed, which also allows for efficient charging of electricity into the sub-battery 7.

[0020] Figure 4 shows the relationship between the battery and the drive motor while the vehicle is running. (A) shows that the drive motor 5 is driven by the main battery 6, causing the electric vehicle 100 to run. At this time, the rotational energy of the front wheels 1 is converted into electricity by the generator motor 4 and stored in the sub-battery 7. (B) shows that the drive motor 5 is driven by the sub-battery 7, causing the electric vehicle 100 to run. At this time, the connection between the generator motor 4 and the sub-battery 7 is cut off by the cutoff switch 12, so the sub-battery 7 is not charged by the generator motor 4.

[0021] FIG. 5 is a flowchart showing switching between the main battery 6 and the sub-battery 7 while the vehicle is running. When a command to run is issued using a lever on the handlebars of the electric vehicle 100, the drive motor 5 is driven by power from the main battery 6 and the vehicle starts running (S10). This causes the rear wheels 2 to rotate and the electric vehicle 100 starts running (S11). It is assumed that the main battery 6 is charged externally before running. After the electric vehicle 100 has run a certain distance, the power of the main battery 6 decreases, and the switching control unit 8 checks whether the power of the main battery 6 has fallen below a threshold value (S12).

[0022] If the power of the main battery 6 is lower than the threshold value, the warning lamp 22 (see FIG. 1) on the top of the handle is illuminated (S13). Then, the changeover switch 13 is switched from the main battery 6 to the sub-battery 7 (S14). Charging of the sub-battery 7 by the generator motor 4 is stopped (S15). Charging of the sub-battery 7 is stopped by turning off the cutoff switch 12. Since power is supplied to the drive motor 5 from the sub-battery 7, the electric vehicle 100 can continue to run (S16).

[0023] When the electric vehicle 100 has traveled a certain distance, the power of the sub-battery 7 decreases, so the switching control unit 8 checks whether the sub-battery 7 has fallen below a threshold value (S17). If the sub-battery 7 is below the threshold value, the warning lamp 23 (see FIG. 1) turns on (S19). Since the vehicle cannot travel any further, the process ends here.

[0024] Returning to the determination in S12, if there is remaining power in the main battery 6, it is checked whether the sub-battery 7 is fully charged (S20). If the sub-battery 7 is not fully charged, the power generator motor 4 charges the sub-battery 7 (S22). If the sub-battery 7 is fully charged, charging of the sub-battery 7 by the power generator motor 4 is stopped (S21). This is done by turning on the cutoff switch 12.

[0025] FIG. 6 is an explanatory diagram illustrating external charging of the main battery 6 and sub-battery 7. The main battery 6 and sub-battery 7 of the electric vehicle 100 have charging terminals 19, 19, and are charged by connecting cables 21, 21 from external chargers 20, 20. Alternatively, the main battery 6 and sub-battery 7 may be removed from the main body 3 and charged. When driving the electric vehicle 100 long distances, the main battery 6 and sub-battery 7 are charged in advance. This allows the vehicle to travel a distance equivalent to the power of the main battery 6 and sub-battery 7. This allows the vehicle to travel a longer distance than if only the main battery 6 were charged and the sub-battery 7 were empty. When the main battery 6 and sub-battery 7 are charged and the electric vehicle 100 is driven, the drive motor 5 is initially driven by the power of the sub-battery 7. When the power of the sub-battery 7 falls below a threshold, the vehicle switches to the main battery 6 for driving. At this time, the sub-battery 7 is charged by the generator motor 4. Therefore, when the power of the main battery 6 falls below the threshold, the vehicle can continue traveling using the power stored in the sub-battery 7. In this embodiment, the sub-battery 7 can have a smaller capacity than the main battery 6 because it cannot store more power than the main battery 6.

[0026] In this embodiment, the configuration in which the generator motor 4 is connected to the sub-battery 7 via the cutoff switch 12 has been described. However, it is also possible to configure the generator motor 4 to be connected to the main battery 6 when the cutoff switch 12 cuts off the connection between the generator motor 4 and the sub-battery 7. As shown in FIG. 2, this can be achieved by providing a line 24 that connects the generator motor 4 and the main battery 6 via the cutoff switch 12. This allows the main battery 6 to be charged by the generator motor 4. As shown in FIG. 7, it is possible to alternate between driving the traction motor 5 with the main battery 6 and charging the sub-battery 7 with the generator motor 4, and driving the traction motor 5 with the sub-battery 7 and charging the main battery 6 with the generator motor 4. [Industrial Applicability]

[0027] The electric vehicle of the present invention is equipped with a main battery 6 and a sub-battery 7, and the sub-battery 7 is charged by a power generating motor 4 that generates electricity through the rotation of the front wheel, making it suitable for electric motorcycles and the like. [Explanation of symbols]

[0028] 1 Front wheels (driven wheels) 2 rear wheels (drive wheels) 3 Main unit 4. Generator motor 5. Drive motor 6 Main battery 7 Sub-battery 8 Switching control section 9 Drive Wheels 10 driven wheel 11 Rotation axis 12. Isolation switch 13 Changeover switch 14A Main battery status detector 14B Sub-battery status detection unit 15 Front wheel axle 16 Belt 17 Converter 18 Inverter 19 Charging terminal 20 External charger 21 Cable 22 Warning lamp A 23 Warning lamp B 24 lines 100 Electric Vehicles

Claims

1. An electric vehicle consisting of an electric two-wheeled vehicle with front wheels as driven wheels and rear wheels as drive wheels, a drive motor that rotates the drive wheels; a power generating motor that generates electricity by rotation of the driven wheel; a main battery that supplies power to the drive motor; a sub-battery having a smaller capacity than the main battery and capable of storing the electric power generated by the power generation motor; a battery state detection unit provided in each of the main battery and the sub-battery, for measuring a remaining charge; a changeover switch that switches the power supply to the drive motor between the main battery and the sub-battery; a cutoff switch that cuts off charging from the power generating motor to the sub-battery, When the main battery and the sub-battery are charged externally to run the electric vehicle, the electric vehicle first runs by driving the drive motor with the power of the sub-battery, and when the power of the sub-battery falls below a threshold, the electric vehicle switches to the main battery and runs while charging the sub-battery with the power generating motor driven by the driven wheels, and when the power of the main battery falls below a threshold, the electric vehicle switches to the sub-battery and runs.

2. 2. The electric vehicle according to claim 1, wherein a large-diameter drive wheel is attached to the driven wheel so as to rotate coaxially, a small-diameter driven wheel is attached to the rotating shaft of the generator motor, and the drive wheel and the driven wheel are connected by a transmission belt.

3. 2. The electric vehicle according to claim 1, wherein the main battery and the sub-battery are externally chargeable via charging terminals.

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