Braking device for saddle-type electric vehicle and saddle-type electric vehicle
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-02-04
- Publication Date
- 2026-08-13
Smart Images
Figure JP2026003919_13082026_PF_FP_ABST
Abstract
Description
Braking Device for Straddle-Type Electric Vehicle and Straddle-Type Electric Vehicle Cross-Reference to Related Applications
[0001] This application is based on Japanese Application No. 2025-019766 filed on February 10, 2025, the contents of which are incorporated herein by reference.
[0002] The present disclosure relates to a braking device for a straddle-type electric vehicle and a straddle-type electric vehicle.
[0003] Conventionally, a technique using regenerative braking force in a straddle-type electric vehicle is known. For example, the vehicle control system disclosed in Patent Document 1 generates regenerative braking force and / or frictional braking force on a drive wheel (rear wheel) and then generates a driving force when there is a driving instruction from a driver of a motorcycle. By increasing the vertical load on the drive wheel by the braking force, the acceleration performance is improved.
[0004] In the regenerative control system of an electric vehicle disclosed in Patent Document 2, an adjustment lever capable of adjusting the regenerative braking force is provided near the left grip separately from the accelerator grip and the brake lever provided on the right side of the handle. Thereby, the mechanical braking force by the brake mechanism and the regenerative braking force by the power generation of the electric motor can be adjusted separately.
[0005] Japanese Patent Application Laid-Open No. 2004-143508 Japanese Patent No. 5478739
[0006] In the drive wheels of the straddle-type electric vehicles in Patent Documents 1 and 2, a friction braking mechanism is provided, and further, braking can also be performed by the regenerative braking force. Therefore, a friction braking mechanism and wiring from the control unit to the friction braking mechanism are required, which increases the component weight and leads to a decrease in electricity cost. In addition, component costs and wiring work costs are incurred.
[0007] An object of the present disclosure is to provide a braking device for a straddle-type electric vehicle that realizes weight reduction and improvement of electricity cost, and a straddle-type electric vehicle equipped with the same.
[0008] The braking system for a saddle-type electric vehicle according to this disclosure is applicable to a partially-wheel-drive saddle-type electric vehicle or a fully-wheel-drive saddle-type electric vehicle. A partially-wheel-drive saddle-type electric vehicle has one or more drive wheels driven by the drive torque of the main motor, and one or more non-drive wheels other than the drive wheels. A fully-wheel-drive saddle-type electric vehicle has two or more wheels, all of which are drive wheels.
[0009] In vehicles with partial wheel drive, at least some of the drive wheels, or in vehicles with all-wheel drive, any of the drive wheels, known as "specific drive wheels," are not equipped with a friction braking mechanism that brakes the wheels using frictional force generated in response to the driver's operation.
[0010] The braking system of this saddle-type electric vehicle includes a drive wheel braking control unit that controls the braking of the drive wheels. The drive wheel braking control unit controls the main motor to brake a specific drive wheel by generating a torque in the opposite direction to the drive torque in the main motor.
[0011] The saddle-type electric vehicle according to this disclosure is equipped with the braking device described above. The main motor is controlled to brake a specific drive wheel by generating a torque in the opposite direction to the drive torque in the main motor.
[0012] This disclosure describes how a specific drive wheel, which does not have a friction braking mechanism, can be braked by generating a torque in the opposite direction to the drive torque in the main motor. By eliminating the friction braking mechanism for the specific drive wheel, it is possible to reduce the weight of the vehicle and improve energy efficiency. It also leads to a reduction in parts costs and wiring costs.
[0013] The above-mentioned and other purposes, features, and benefits of this disclosure will be further clarified by the detailed description below, with reference to the attached drawings. Figure 1 shows the braking pattern of a partially-wheel-drive saddle-type electric vehicle according to this embodiment; Figure 2 shows the braking pattern of a fully-wheel-drive saddle-type electric vehicle according to this embodiment; Figure 3 is a right side view of a partially-wheel (rear-wheel)-drive saddle-type electric vehicle; Figure 4 shows an example of the configuration of the operating means; Figure 5 is a schematic cross-sectional view of a mechatronic integrated motor; Figure 6 is a circuit configuration diagram of two main motor drive circuits and the main motor; Figure 7 is a functional arrangement diagram of the drive control unit of the first embodiment; Figure 8 is a functional arrangement diagram of the drive control unit of the second embodiment; Figure 9 is a functional arrangement diagram of the drive control unit of the third embodiment; Figure 10 is a diagram of an embodiment in which this embodiment is applied to a vehicle with front-wheel hydraulic brakes; Figure 11 is a diagram of an embodiment in which a vibration actuator is installed on the handle grip; and Figure 12 is a diagram of an eccentric motor which is an example of the configuration of a vibration actuator.
[0014] Braking devices for saddle-type electric vehicles and several embodiments of saddle-type electric vehicles will be described based on the drawings. The first to third embodiments described below relate to the functional arrangement of the drive control unit into which the braking device is built, and these are collectively referred to as "this embodiment." Saddle-type electric vehicles are so-called electric motorcycles, including electric two-wheeled vehicles and electric three-wheeled vehicles.
[0015] In this specification, "vehicle" means a saddle-type electric vehicle. All saddle-type electric vehicles are equipped with one or more drive wheels driven by the drive torque of the main motor. In addition, "partially wheel-driven" saddle-type electric vehicles are equipped with one or more non-driven wheels other than the drive wheels. In "all-wheel-driven" saddle-type electric vehicles, all two or more wheels are drive wheels.
[0016] Regarding the braking means for each wheel, in conventional saddle-type electric vehicles, both the drive wheels and non-drive wheels are braked using friction brakes. Friction brakes (friction braking mechanisms) brake the wheels using the frictional force generated in response to the driver's operation, and include non-by-wire (hydraulic piping) hydraulic brakes, as well as by-wire electric brakes and hydraulic brakes. In addition, there is a conventional technology that utilizes regenerative braking force for the drive wheels, but this is premised on the combined use of friction braking force from friction brakes and regenerative braking force. As a result, the weight of the components increases, leading to a decrease in energy efficiency, and the costs of components and wiring work have been a challenge.
[0017] In contrast, in this embodiment, the friction brake is eliminated for the "specific drive wheel" among the drive wheels, and braking is performed by generating a torque in the opposite direction to the drive torque in the main motor. Here, the energy generated by the torque in the opposite direction to the drive torque is often used to regenerate power into the battery through the generation of power by the main motor, so in the following description of the embodiment, "braking by torque in the opposite direction to the drive torque" will be simply described as "regenerative braking". However, strictly speaking, there is a possibility that the energy generated by the torque in the opposite direction to the drive torque may be used for purposes other than regenerative power, so the above expression is used for greater accuracy.
[0018] Referring to Figures 1 and 2, the braking patterns of each wheel in partially-wheel-drive and fully-wheel-drive electric two-wheeled and electric three-wheeled vehicles are explained. In the diagrams, driven wheels are shown with thick lines, and non-driven wheels with thin rectangles. Wheels that are regeneratedly braked are indicated with a backward-pointing arrow, and wheels that are frictionally braked are indicated with horizontal hatching. In addition, for both electric two-wheeled and electric three-wheeled vehicles, the designation for the front wheels is "91" and the designation for the rear wheels is "92," with "d" added to the end of the designation for driven wheels and "n" for non-driven wheels. In electric three-wheeled vehicles, the left and right pairs of wheels are of the same specifications.
[0019] Figure 1 shows rear-wheel drive vehicles 901-903 and front-wheel drive vehicles 904-906 as partially wheel-drive saddle-type electric vehicles. Vehicle 901 is a typical electric two-wheeler in which the front wheel 91n is a non-driven wheel and the rear wheel 92d is a driven wheel. Vehicle 902 is an electric three-wheeler equipped with one non-driven front wheel 91n and two driven rear wheels 92d. Vehicle 903 is an electric three-wheeler equipped with two non-driven front wheels 91n and one driven rear wheel 92d.
[0020] Vehicle 904 is an electric two-wheeled vehicle in which the front wheels 91d are driven wheels and the rear wheels 92n are non-driven wheels. Vehicle 905 is an electric three-wheeled vehicle equipped with one driven front wheel 91d and two non-driven rear wheels 92n. Vehicle 906 is an electric three-wheeled vehicle equipped with two driven front wheels 91d and one non-driven rear wheel 92n.
[0021] In the partially driven vehicles 901-906, at least some of the drive wheels, i.e., one or two drive wheels, become "specific drive wheels" and are subjected to regenerative braking. On the other hand, one or two non-drive wheels are subjected to friction braking by friction brakes.
[0022] Figure 2 shows the all-wheel-drive saddle-type electric vehicles 991-996. The configuration of each vehicle 991-996 is the same as that of the partially-wheel-drive vehicles 901-906, with the non-driven wheels replaced by driven wheels, as indicated by the third digit of the designation. Therefore, a detailed explanation of the individual configurations is omitted. In the all-wheel-drive vehicles 991-996, some of the driven wheels become "specific driven wheels," and the other driven wheels are friction-braked. In other words, in vehicle 991-993, where the rear wheel 92d is a specific driven wheel and is regeneratedly braked, the front wheel 91d is friction-braked, and in vehicle 994-996, where the front wheel 91d is a specific driven wheel and is regeneratedly braked, the rear wheel 92d is friction-braked.
[0023] However, even for drive wheels that are subjected to friction braking, regenerative braking may be used in conjunction with friction braking to decelerate the vehicle before bringing it to a complete stop. During braking, the load shifts to the front wheels, so by applying regenerative braking to both the front wheels 91d and the rear wheels 92d, it becomes possible to generate a greater braking force and decelerate the vehicle, thereby efficiently recovering energy through regeneration. For example, after decelerating to a predetermined vehicle speed or below, friction braking of "non-specific drive wheels" other than the specific drive wheels enables a complete stop with minimal friction loss.
[0024] In both partial-wheel drive and all-wheel drive systems, friction brakes are not provided on specific drive wheels. By eliminating friction brakes on one specific drive wheel in electric two-wheeled vehicles, and on one or two specific drive wheels in electric three-wheeled vehicles, it is possible to reduce vehicle weight and improve energy efficiency. This also leads to a reduction in parts costs and wiring costs.
[0025] Next, with reference to Figures 3 and 4, the specific configuration of the saddle-type electric vehicle of this embodiment will be described. Figure 3 shows a rear-wheel-drive electric motorcycle 901 in which the front wheels 91n are non-driven wheels and the rear wheels 92d are driven wheels. The rear wheels 92d are driven by the driving torque of the main motor 50. The electric motorcycle 901 is equipped with a handle 80 operated by the driver, a right foot (brake) pedal 86, etc.
[0026] In this embodiment, the drive control unit 20 that controls the drive of the main motor 50 is integrated with the main motor 50, forming a mechatronic integrated motor 10 (see Figure 5). By adopting a mechatronic integrated structure, miniaturization and reduction of wiring losses are greatly improved. The mounting position of the mechatronic integrated motor 10 is not limited to the position below the handle 80 as illustrated in Figure 3, but may also be mounted in the space under the seat, for example.
[0027] The braking system according to this embodiment is built into the drive control unit 20 and includes a drive wheel braking control unit 25, a non-drive wheel braking control unit 26 (see Figures 4, 7, etc.), etc. When the driver performs a braking operation, the drive wheel braking control unit 25 controls the main motor 50 to brake the rear wheels 92d by generating a torque in the opposite direction to the drive torque in the main motor 50. The non-drive wheel braking control unit 26 brakes the front wheels 91n by driving an electric brake motor, for example, in a by-wire system, to generate a pressing force on the friction brake 61.
[0028] Referring to Figure 4, an example of braking operation will be explained. The handlebars 80 are equipped with a left-hand grip 81, a right-hand grip 82, a left-hand lever 83, and a right-hand lever 84. Accelerator operation is mainly performed using the right-hand grip 82. Brake operation means include a brake lever, a brake pedal, or both, and the following combinations are for example.
[0029] (a) Front wheel: Right hand lever 84, Rear wheel: Left hand lever 83 (b) Front wheel: Right hand lever 84, Rear wheel: Right foot pedal 86 (c) Right hand lever 84 and left hand lever 83, regardless of front or rear wheel
[0030] In (a), a rear wheel brake signal from the left hand lever 83 is input to the drive wheel braking control unit 25 of the drive control unit 20, and in (b), a rear wheel brake signal from the right foot pedal 86 is input to the drive wheel braking control unit 25. In (a) and (b), a front wheel brake signal from the right hand lever 84 is input to the non-drive wheel braking control unit 26 of the drive control unit 20. In (c), brake signals from the left hand lever 83 and the right hand lever 84 are input to both the drive wheel braking control unit 25 and the non-drive wheel braking control unit 26, for example, and the drive wheel braking control unit 25 and the non-drive wheel braking control unit 26 work together to perform braking control.
[0031] Next, referring to Figure 5, the configuration of the electromechanical integrated motor 10, in which the main motor 50 and the drive control unit 20 are integrated, will be described. The housing 11 includes a cylindrical motor housing section 111 and a roughly rectangular parallelepiped unit housing section 112. The main motor 50 is housed in the motor housing section 111. The circuit board 21 of the drive control unit 20 is housed in the space formed by the unit housing section 112 and the cover 12. For example, a connector 13 into which power and signal lines are input is provided on one side of the unit housing section 112.
[0032] The main motor 50 is, for example, a three-phase brushless motor and includes a stator 54, a rotor 55, and a shaft 56. The stator 54 is fixed to the inner circumferential wall of the motor housing 111 of the housing 11. Two sets of three-phase windings 501 and 502 are wound around the stator 54, and the ends of each set of windings are connected to the circuit board 21. In addition, if we include the case of multi-phase motors other than three-phase, the term "three-phase winding" is generally used to refer to "multi-phase winding".
[0033] The rotor 55 is located radially inward of the stator 54 and has permanent magnets (not shown) embedded in it. The shaft 56 is fitted along the axis of the rotor 55. When the three-phase windings 501 and 502 are energized, the rotor 55 and shaft 56 rotate together due to the rotating magnetic field formed in the stator 54.
[0034] A sensor magnet 571 is provided at the end of the shaft 56 opposite to the output end 58. A rotation detection element 572 mounted on the circuit board 21 detects the rotation of the rotor 55 by detecting changes in the magnetic field of the sensor magnet 571. The pair of the sensor magnet 571 and the rotation detection element 572 constitutes a rotation angle sensor 57. The output end 58 of the shaft 56 is engaged with a transmission gear 59, and the rotation of the shaft 56 is transmitted to the drive wheel (rear wheel 92d) via the transmission gear 59. The main motor 50, rotation angle sensor 57, and transmission gear 59 together are called the mechanical unit 150.
[0035] Next, referring to Figure 6, the circuit configuration of the two main motor drive circuits 451 and 452 and the main motor 50 will be described. The main motor 50 is a three-phase brushless motor having two sets of three-phase windings 501 and 502. The first winding 501 consists of a U-phase winding 511, a V-phase winding 512, and a W-phase winding 513. The second winding 502 consists of a U-phase winding 521, a V-phase winding 522, and a W-phase winding 523.
[0036] The two main motor drive circuits 451 and 452 are provided in correspondence with the three-phase windings 501 and 502, and convert the DC power supplied from the high-voltage battery 40 into three-phase AC power and supply it to the three-phase windings 501 and 502. The main motor drive circuits 451 and 452 are composed of three-phase inverters in which six switching elements such as MOSFETs are bridge-connected between a high-potential line Lp and a low-potential line Lg.
[0037] A capacitor 44 is connected in parallel with the high-voltage battery 40 to the input side of the main motor drive circuits 451 and 452. In addition, current sensors 471 and 472, which detect the three-phase currents Iu1, Iv1, Iw1, Iu2, Iv2, and Iw2 of each system and output them to the main motor control unit 35, are provided, for example, on the low-potential side of the lower arm switching element.
[0038] The main motor control unit 35 acquires the three-phase currents Iu1, Iv1, Iw1, Iu2, Iv2, and Iw2 from the current sensors 471 and 472, and also acquires the motor rotation angle θ from the rotation angle sensor 87 provided on the main motor 50. In addition, a torque command is input to the main motor control unit 35 from a higher-level control circuit (not shown). Based on this information, the main motor control unit 35 calculates a voltage command.
[0039] The main motor drive circuits 451 and 452 drive the main motor 50 by switching according to the voltage commands calculated by the main motor control unit 35. When the driver operates the accelerator, the main motor 50 outputs drive torque to the drive wheels (rear wheels 92d) through powering. On the other hand, when the driver operates the brake, the main motor 50 outputs torque in the opposite direction to the drive torque to the drive wheels (rear wheels 92d) through regenerative braking.
[0040] As described above, in the electromechanically integrated motor 10 of this embodiment, the three-phase windings 501 and 502 of the main motor 50 and the main motor drive circuits 451 and 452 are configured in a redundant two-system configuration. By using a parallel circuit compared to a single system, the effect of suppressing element current and heat generation can be obtained. In addition, since braking force can be secured by the other functioning system when one system fails, reliability is ensured even if friction brakes are eliminated. In other embodiments, a redundant configuration of three or more systems may be used. Hereinafter, configurations of two systems and three or more systems will be referred to as "configurations of two or more systems".
[0041] Next, the functions of the drive control unit 20 will be described. In this embodiment, the drive control unit 20 performs control related to the braking and driving of at least the drive wheels with a single unit, and in some embodiments, it also performs control related to the braking of the non-drive wheels. Therefore, compared to a configuration in which separate units communicate with each other, communication delay is reduced and vehicle controllability is improved.
[0042] The drive control unit 20 is configured as an ECU mainly including, for example, a microcomputer. Inside the drive control unit 20, there are a CPU, a ROM, a RAM, an I / O, and bus lines connecting these components, which are not shown in the figure. The drive control unit 20 executes control by software processing in which a program stored in advance is executed by the CPU and by hardware processing using a dedicated electronic circuit.
[0043] Referring to FIGS. 7 to 9, the first to third embodiments regarding the functional arrangement of the drive control unit 20 applied to a rear-wheel drive electric two-wheeler 901 will be described. The reference numerals of the drive control units in the first, second, and third embodiments are 201, 202, and 203, respectively. Commonly in the first to third embodiments, the drive control units 201-203 include a low-voltage part 310 and a high-voltage part 410 that are insulated from each other.
[0044] The circuit board 21 (see FIG. 5) constituting the drive control units 201-203 may be divided into a plurality of sheets. For example, the low-voltage part 310 and the high-voltage part 410 may be mounted on different substrates. The connector 13 (see FIG. 5) may preferably separate the high-voltage power connector and the low-voltage signal connector. Also, in a configuration of two or more systems, the connectors may be separated for each system.
[0045] For example, a voltage of 96 [V] is supplied from the high-voltage battery 40 to the high-voltage part 410. Also, the voltage of the high-voltage battery 40 is stepped down to, for example, 12 [V] by the step-down power supply 42 and supplied to the low-voltage part 310. Thereby, the low-voltage battery becomes unnecessary, and the mounting space, wiring, etc. can be reduced. However, in other embodiments, a low-voltage battery may be mounted. The voltage stepped down by the step-down power supply 42 may be supplied to other ECUs. The step-down power supply 42 may be provided outside instead of being built into the drive control units 201-203.
[0046] The drive control units 201 - 203 include a CAN circuit 32, sensor signal receivers 331, 332, 333, and an inertial sensor 34 as the configuration of the input system of the low - voltage section 310. Information such as from a meter is input to the CAN circuit 32. The sensor signal receivers 331, 332, 333 receive one or more types of sensor signals detected for the driver's operation or vehicle behavior. The sensor signal receiver 331 receives the sensor signal of the accelerator grip. The sensor signal receiver 332 receives the sensor signal of the brake lever or brake pedal. The sensor signal receiver 333 receives the wheel speed sensor signal of the front wheel 91n. The wheel speed of the rear wheel 92d can be substituted with a value converted from the rotation speed of the main motor 50 detected by the rotation angle sensor 57.
[0047] In common with the first to third embodiments, the drive wheel braking control unit 25 is constituted by the main motor control unit 35 provided in the low - voltage section 310 and the main motor drive circuit 45 provided in the high - voltage section 410. The drive wheel braking control unit 25 controls the braking of the drive wheels based on the sensor signals received by the sensor signal receivers 331, 332, 333. Specifically, the drive wheel braking control unit 25 functions as a "drive wheel drive - braking control unit" including both driving and braking, but in this embodiment, a name focusing on the braking function is used from the perspective of the braking device.
[0048] In a configuration of two or more systems, the main motor drive circuit 45 is configured for each system (see FIG. 6). The main motor drive circuit 45 supplies power to the main motor 50 to drive it. In the mechanical unit 150, the rotation speed of the main motor 50 is detected by the rotation angle sensor 57 and fed back to the main motor control unit 35. The output of the main motor 50 is transmitted to the drive wheels via the transmission gear 59.
[0049] Paying particular attention to regenerative braking, the output of the main motor 50 is transmitted to a specific drive wheel via the transmission gear 59. Thus, the main motor 50 is controlled so as to brake a specific drive wheel (the rear wheel 92d) by generating a torque opposite to the driving torque in the main motor 50 in the vehicle 901.
[0050] Furthermore, the braking device built into the drive control units 201-203 of the first to third embodiments has a vehicle control unit 29 in the low-pressure section 310. The vehicle control unit 29 controls the driving force and braking force of the vehicle 901 based on sensor signals received by the sensor signal receiving units 331, 332, and 333. For example, the vehicle control unit 29 may control the driving force and braking force using sensor signals such as an acceleration sensor or a gyro sensor.
[0051] Furthermore, the braking devices built into the drive control units 202 and 203 of the second and third embodiments include non-drive wheel braking control units 262 and 263. In this case, the braking device is assumed to be applied to a partially wheel-driven vehicle equipped with non-drive wheels. The non-drive wheel braking control units 262 and 263 control the braking of the non-drive wheels based on sensor signals received by the sensor signal receiving units 331, 332, and 333. For example, if the friction brake of the non-drive wheel (front wheel 91n) is a non-by-wire (hydraulic piping) hydraulic brake, it is assumed that ABS control will be performed based on sensor signals such as wheel speed sensors and hydraulic pressure sensors.
[0052] Furthermore, it is conceivable that the friction brakes on the non-driven wheels (front wheels 91n) are either by-wire electric brakes or hydraulic brakes. For example, in electric brakes (EMB), the rotational motion of the front wheel brake motor 60 is converted into linear motion, generating pad pressure on the brake caliper. In hydraulic brakes, the front wheel brake motor 60 rotates a hydraulic pump, generating braking hydraulic pressure. By controlling both the rear wheels 92d and the front wheels 91n using a by-wire system, the effects of communication delays can be suppressed, enabling more advanced vehicle control.
[0053] When applied to a vehicle equipped with an electric parking brake (EPB) 64, the non-drive wheel braking control units 262 and 263 may incorporate a drive circuit for the actuator (motor, electric cylinder, solenoid, etc.) of the parking brake 64.
[0054] The non-drive wheel braking control unit 262 of the second embodiment consists of an auxiliary actuator control unit 36 and an auxiliary actuator drive circuit 366 provided in the low-pressure section 310. In Figure 8, the auxiliary actuator is denoted as "Auxiliary Act". For example, the auxiliary actuator drive circuit 366 is composed of an H-bridge circuit that can switch the direction of the current during braking and release to rotate the DC motor in forward and reverse directions.
[0055] The non-drive wheel braking control unit 262 of the third embodiment consists of an auxiliary actuator control unit 36 provided in the low-pressure section 310, and an auxiliary actuator drive circuit 46 provided in the high-pressure section 410 in conjunction with the main motor drive circuit 45. In Figure 9, the auxiliary actuator is denoted as "Auxiliary Act".
[0056] For example, Japanese Patent Publication No. 7226390 discloses a technique in which a portion of the legs of an inverter circuit for a three-phase AC motor and an H-bridge circuit for a DC motor are shared. By utilizing this technique, the total number of switching elements in the main motor drive circuit 45 and the auxiliary actuator drive circuit 46 can be reduced, enabling miniaturization.
[0057] Furthermore, for example, if both the regenerative braking of the rear wheels 92d and the electric brakes of the front wheels 91n are controlled by a drive-by-wire system, the drive wheel braking control unit 25 and the non-drive wheel braking control units 262 and 263 work together to enable integrated braking control without the driver having to be aware of the distinction between the front and rear wheels. In other words, it becomes possible to operate the brakes with the same feel as a four-wheeled vehicle.
[0058] When applied to all-wheel drive vehicles, the term "non-drive wheel braking control unit" may be interpreted as "non-specific drive wheel braking control unit" which applies to non-specific drive wheels. For example, in an all-wheel drive electric motorcycle 991 (see Figure 2), when regenerative braking is performed on both the front wheel 91d and the rear wheel 92d, and then friction braking is performed on the front wheel 91d, the "specific drive wheel braking control unit" and the "non-specific drive wheel braking control unit" work together to smoothly execute a series of braking actions.
[0059] Furthermore, focusing on the drive control function of the main motor 50 by the drive wheel braking control unit 25, when the brakes and accelerator of the drive wheels are operated simultaneously, the drive wheel braking control unit 25 can control the output of the main motor 50 to be the difference between the required driving force and the required braking force. The drive wheel braking control unit 25 may also calculate the output of the main motor 50 by changing the weighting of braking and driving based on vehicle information such as vehicle speed.
[0060] The drive control units 201-203 can also be equipped with drive functions for the vibration actuator 68 (see Figure 11), which will be described later, and for lighting fixtures such as brake lights and hazard lights. In configurations with two or more systems, by separating the functions of driving the vibration actuator 68 and auxiliary equipment / lighting fixtures for each system, it is possible to ensure redundancy in the driving and braking of the main motor 50, as well as further enhance safety during vehicle operation.
[0061] Next, referring to Figure 10, an example in which this embodiment is applied to a vehicle 901 in which the front wheels 91n are equipped with hydraulic brakes will be described. The hydraulic brakes on the front wheels 91n are mainly operated by the right grip. As a comparative example, if hydraulic brakes are also used on the rear wheels 92d, it is necessary to place the ABS unit 66 at the rear of the vehicle and run hydraulic piping from the front to the rear of the vehicle, as shown by the dashed line.
[0062] In this embodiment, by eliminating the hydraulic brake on the rear wheel 92d, a compact ABS unit 66 for one front wheel 91n can be placed at the front of the vehicle, as shown by the solid line, eliminating the need to route hydraulic piping to the rear. Therefore, the cargo space under the seat and other layout possibilities are improved.
[0063] Next, with reference to Figures 11 and 12, an embodiment will be described in which a vibration actuator 70 that signals an abnormality is provided in the operating unit operated by the driver. As shown in Figure 11, for example, the vibration actuator 70 is built into the left hand grip 81 and the right hand grip 82 of the steering wheel 80. In other embodiments, the vibration actuator 70 may be provided in the right foot pedal 86 instead of or in addition to the grips 81 and 82.
[0064] The drive control unit 20 further includes a vibration actuator drive circuit 27. When a brake abnormality is detected, the vibration actuator drive circuit 27 vibrates the vibration actuator 70 to notify the driver of the abnormality. For example, when it is detected that the maximum braking force of the friction brake of a non-driven wheel (front wheel 91n) has decreased from the normal value, the vibration actuator 70 vibrates the grips 81 and 82 to inform the driver of the abnormality and prompts them to release the accelerator and operate the rear wheel brake. Alternatively, after the vibration actuator 70 notifies the driver of the abnormality, it may automatically reduce the driving force and activate the brakes of the normal wheels without waiting for the driver's operation.
[0065] Even if it is not an abnormality, if the braking force reaches its upper limit during braking and no further braking force can be obtained, the vibration actuator 70 may also provide notification. Notification by the vibration actuator 70 may be used in conjunction with notification by a meter or other display.
[0066] The vibration actuator 70 is composed of an eccentric motor in which an eccentric weight 72 is attached to one side of the motor shaft 71, as shown in Figure 12, for example. Alternatively, the vibration actuator 70 may be composed using a piezoelectric element. The vibration actuator drive circuit 27 may be controlled to vibrate only the part corresponding to the detected abnormality or the reaching of the upper limit. This makes it possible for the driver to intuitively understand where the abnormality has occurred.
[0067] (Other embodiments) (a) The structure is not limited to the integrated electromechanical motor 10, but may also be a structure in which the drive control unit 20 and the main motor 50 are separated.
[0068] (b) The drive control unit 20 does not have all of the drive wheel braking control unit 25, non-drive wheel braking control unit 26, and vehicle control unit 29, and some functions may be configured in separate units. Also, sensor signal receiving units 331, 332, and 333 may be provided separately from the drive control unit 20, and sensor signals may be communicated to the drive control unit 20.
[0069] (c) The main motor 50 and the main motor drive circuit 45 are not limited to a redundant configuration of two or more systems, but may be configured as a single system.
[0070] The present disclosure is not limited to these embodiments and can be implemented in various forms without departing from its spirit.
[0071] (Disclosure of Technical Ideas) This specification discloses several technical ideas as described in the following paragraphs. Some paragraphs are written in a multiple dependent form, where subsequent paragraphs optionally refer to preceding paragraphs. Furthermore, some paragraphs are written in a multiple dependent form, where they refer to other multiple dependent forms. These paragraphs written in multiple dependent forms define several technical ideas.
[0072] (Technical Concept 1) A brake device for a saddle-type electric vehicle, comprising a partially-wheel-drive saddle-type electric vehicle (901-906) having one or more drive wheels (92d, 91d) driven by the driving torque of a main motor (50), and one or more non-drive wheels (91n, 92n) other than the drive wheels, or a fully-wheel-drive saddle-type electric vehicle (991-996) in which two or more wheels are drive wheels, wherein a friction braking mechanism that brakes the wheels by frictional force generated in response to the driver's operation is not provided for specific drive wheels, which are at least some of the drive wheels in the partially-wheel-drive vehicle, or any of the drive wheels in the fully-wheel-drive vehicle, and comprising a drive wheel braking control unit (25) that controls the braking of the drive wheels, wherein the drive wheel braking control unit controls the main motor so as to brake the specific drive wheels by generating a torque in the opposite direction to the driving torque of the main motor. (Technical Concept 2) A braking device for a saddle-type electric vehicle according to Technical Concept 1, wherein the multiphase windings (501, 502) wound around the stator (54) of the main motor, and the main motor drive circuits (451, 452) that supply power to the multiphase windings, are configured in a redundant configuration of two or more systems. (Technical Concept 3) A braking device for a saddle-type electric vehicle according to Technical Concept 1 or 2, comprising a drive control unit (201, 202, 203) that controls the drive of the main motor, and a sensor signal receiving unit (331, 332, 333) that receives one or more sensor signals detecting driver operations or vehicle behavior, and a drive wheel braking control unit, wherein the drive wheel braking control unit controls the braking of the drive wheels based on the sensor signals. (Technical Concept 4) A braking device for a saddle-type electric vehicle according to any one of Technical Concepts 1 to 3, comprising: a drive control unit (202, 203) that controls the drive of the main motor, which has a sensor signal receiving unit (331, 332, 333) built into it that receives one or more sensor signals that detect the driver's operation or the vehicle's behavior; and a non-drive wheel braking control unit (26, 262, 263) that controls the braking of the non-drive wheels based on the sensor signals.(Technical Concept 5) A braking device for a saddle-type electric vehicle according to any one of Technical Concepts 1 to 4, comprising: a drive control unit (201, 202, 203) that controls the drive of the main motor, and a sensor signal receiving unit (331, 332, 333) that receives one or more sensor signals detecting the driver's operation or vehicle behavior, and a vehicle control unit (29) that controls the driving force and braking force of the vehicle based on the sensor signals. (Technical Concept 6) A braking device for a saddle-type electric vehicle according to any one of Technical Concepts 1 to 5, wherein the drive control unit (20) that controls the drive of the main motor is configured integrally with the main motor. (Technical Concept 7) A saddle-type electric vehicle equipped with a braking device for a saddle-type electric vehicle according to any one of Technical Concepts 1 to 6, wherein the main motor is controlled to brake a specific drive wheel by generating a torque in the opposite direction to the driving torque in the main motor.
[0073] The control units (drive wheel braking control unit, non-drive wheel braking control unit, vehicle control unit) and methods described herein may be implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. Alternatively, the control units and methods described herein may be implemented by a dedicated computer provided by configuring a processor by one or more dedicated hardware logic circuits. Alternatively, the control units and methods described herein may be implemented by one or more dedicated computers configured by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by the computer on a computer-readable non-transitional tangible recording medium.
[0074] This disclosure is described in accordance with embodiments. However, this disclosure is not limited to such embodiments and structures. This disclosure also includes various modifications and variations within the scope of equivalents. Furthermore, various combinations and forms, as well as other combinations and forms that include only one, more, or fewer elements, fall within the scope and idea of this disclosure.
Claims
1. A braking device for a saddle-type electric vehicle, comprising a partially-wheel-drive saddle-type electric vehicle (901-906) having one or more drive wheels (92d, 91d) driven by the driving torque of a main motor (50), and one or more non-drive wheels (91n, 92n) other than the drive wheels, or a fully-wheel-drive saddle-type electric vehicle (991-996) in which two or more wheels are drive wheels, wherein a friction braking mechanism that brakes the wheels by frictional force generated in response to the driver's operation is not provided for specific drive wheels, which are at least some of the drive wheels in the partially-wheel-drive vehicle, or any of the drive wheels in the fully-wheel-drive vehicle, and comprising a drive wheel braking control unit (25) that controls the braking of the drive wheels, wherein the drive wheel braking control unit controls the main motor so as to brake the specific drive wheels by generating a torque in the opposite direction to the driving torque of the main motor.
2. The braking device for a saddle-type electric vehicle according to claim 1, wherein the multiphase windings (501, 502) wound around the stator (54) of the main motor, and the main motor drive circuits (451, 452) that supply power to the multiphase windings, are configured in a redundant configuration of two or more systems.
3. A braking device for a saddle-type electric vehicle according to claim 1, comprising: a drive control unit (201, 202, 203) that controls the drive of the main motor, and a sensor signal receiving unit (331, 332, 333) that receives one or more sensor signals that detect the driver's operation or vehicle behavior, and a drive wheel braking control unit, wherein the drive wheel braking control unit controls the braking of the drive wheels based on the sensor signals.
4. A braking device for a saddle-type electric vehicle according to claim 1, comprising: a sensor signal receiving unit (331, 332, 333) built into a drive control unit (202, 203) that controls the drive of the main motor, which receives one or more sensor signals that detect the driver's operation or the vehicle's behavior; and a non-drive wheel braking control unit (26, 262, 263) that controls the braking of the non-drive wheels based on the sensor signals.
5. A braking device for a saddle-type electric vehicle according to claim 1, comprising: a drive control unit (201, 202, 203) that controls the drive of the main motor, and a sensor signal receiving unit (331, 332, 333) that receives one or more sensor signals that detect the driver's operation or the vehicle's behavior, and a vehicle control unit (29) that controls the driving force and braking force of the vehicle based on the sensor signals.
6. The braking device for a saddle-type electric vehicle according to claim 1, wherein the drive control unit (20) that controls the drive of the main motor is configured integrally with the main motor.
7. A saddle-type electric vehicle equipped with a braking device according to any one of claims 1 to 6, wherein the main motor is controlled to brake the specific drive wheel by generating a torque in the same direction as the drive torque in the main motor.