Brake systems and saddle-type vehicles

Abstract

The purpose of the present invention is to provide a brake system and saddle-riding type vehicle whereby it is possible to improve safety during braking. A brake system 100 includes a front-wheel braking unit 20 that brakes a front wheel 3, a rear-wheel braking unit 40 that brakes a rear wheel 4, and an operation element 11 operated by a rider. The front-wheel braking unit 20 includes a friction-type front-wheel braking mechanism 21a that is connected to the operation element 11 by hydraulic pressure and that brakes the front wheel 3 by using frictional force corresponding to the hydraulic pressure. The rear-wheel braking unit 40 includes a regenerative braking mechanism 5 that causes the rear wheel 4 to generate a regenerative braking force corresponding to rotation of the rear wheel 4, and a by-wire friction-type rear-wheel braking mechanism 21b that is not connected to the operation element 11 by hydraulic pressure and that brakes the rear wheel 4 by using a frictional force corresponding to control of actuators 35b, 38b, and 73.

Description

Technical Field

[0001] The present invention relates to a braking system for a saddle-type vehicle and a saddle-type vehicle equipped with the braking system.

Background Art

[0002] Conventionally, as a braking system for a saddle-type vehicle, for example, there is a braking system for a motorcycle in which the rear wheel is driven by an electric motor, and a regenerative braking mechanism that applies regenerative torque generated by causing the electric motor to function as a generator by the rotation of the rear wheel to the rear wheel for braking, and a friction braking mechanism that generates frictional force on the front wheel for braking in response to an operation of a brake lever by a rider (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a braking system configured as described in Patent Document 1, the regenerative braking mechanism functions as a generator by inputting the rotational force of the rear wheel to the rotation shaft of the electric motor, and brakes the rear wheel of the saddle-type vehicle by the regenerative torque generated during power generation. Therefore, for example, when the rotational speed of the rear wheel to which the electric motor is connected is low, or when the rotation of the rear wheel has stopped, the regenerative braking force that can be generated by the regenerative braking mechanism may be insufficient with respect to the target value. Further, for example, when the generated power cannot be stored by a storage battery and the electric motor cannot function as a generator, the regenerative braking force may not be generated, and there is a risk that the saddle-type vehicle cannot be stopped from a running state or maintained in a stopped state.

[0005] This invention was made against the backdrop of the above-mentioned problems, and aims to provide a brake system for a saddle-type vehicle that can improve safety during braking. It also aims to provide a saddle-type vehicle equipped with such a brake system. [Means for solving the problem]

[0006] The brake system according to the present invention is a brake system for a rear-wheel drive saddle-type vehicle, and includes a front wheel braking unit for braking the front wheel of the saddle-type vehicle, a rear wheel braking unit for braking the rear wheel of the saddle-type vehicle, and an operator operated by the rider of the saddle-type vehicle, wherein the front wheel braking unit includes a friction-type front wheel braking mechanism that is hydraulically connected to the operator and brakes the front wheel with a frictional force corresponding to the hydraulic pressure, the rear wheel braking unit includes a regenerative braking mechanism that generates a regenerative braking force on the rear wheel corresponding to the rotation of the rear wheel, and the rear wheel braking unit further includes a by-wire type friction-type rear wheel braking mechanism that is not hydraulically connected to the operator and brakes the rear wheel with a frictional force corresponding to the control of the actuator.

[0007] The saddle-type vehicle according to the present invention is configured to include the brake system described above.

[0008] With this configuration, the rear wheel braking unit is equipped with a regenerative braking mechanism and a drive-by-wire friction-type rear wheel braking mechanism that is not hydraulically connected to the actuator but brakes the rear wheel with frictional force corresponding to the actuator's control. By controlling the actuator, a predetermined frictional force corresponding to that control can be applied to the rear wheel, thereby improving safety during braking. [Brief explanation of the drawing]

[0009] [Figure 1] This is a diagram illustrating the saddle-type vehicle according to Embodiment 1. [Figure 2] This is a diagram illustrating the brake system according to Embodiment 1. [Figure 3] This is a diagram illustrating the hydraulic pressure adjustment unit according to Embodiment 1. [Figure 4] This is a diagram illustrating the system configuration of the brake system according to Embodiment 1. [Figure 5] This is a diagram illustrating the brake system according to Embodiment 2. [Figure 6] This is a diagram illustrating the actuator according to Embodiment 2. [Figure 7] This is a diagram illustrating the system configuration of the brake system according to Embodiment 2. [Modes for carrying out the invention]

[0010] Embodiments for implementing the brake system according to the present invention and a saddle-type vehicle equipped with the brake system will be described below with reference to the drawings. In the embodiments, the case in which the brake system according to the present invention is applied to a motorcycle as a saddle-type vehicle will be described. Note that the brake system according to the present invention may be applied to other types of motorcycles besides motorcycles. Motorcycles include three-wheeled vehicles. Motorcycles and three-wheeled vehicles include motorcycles, scooters, electric scooters, etc.

[0011] The configurations and operations described in the embodiments are examples only, and the brake system and saddle-type vehicle according to the present invention are not limited to such configurations and operations. In addition, in each figure, the same or similar members or parts may be denoted by the same reference numeral, or the reference numeral may be omitted. Furthermore, detailed structural information may be simplified or omitted as appropriate. In addition, redundant or similar descriptions may be simplified or omitted as appropriate.

[0012] <Embodiment 1> Embodiment 1 of the brake system according to the present invention and a saddle-type vehicle equipped with the brake system will be described with reference to the drawings.

[0013] Figure 1 is a diagram illustrating a saddle-type vehicle equipped with the brake system according to Embodiment 1. Figure 2 is a diagram illustrating the brake system according to Embodiment 1. Figure 3 is a diagram illustrating the hydraulic pressure adjustment unit of the brake system according to Embodiment 1. Figure 4 is a diagram illustrating the system configuration of the brake system according to Embodiment 1.

[0014] <About saddle-type vehicles> As shown in Figure 1, the motorcycle 10, which is a saddle-type vehicle, includes a body 1, a handle 2 that is rotatably held on the body 1, a front wheel 3 that is rotatably held on the body 1 together with the handle 2, a rear wheel 4 that is rotatably held on the body 1, an electric motor 5 (see Figure 2) that serves as a drive source for driving the rear wheel 4, a power supply unit 6 (see Figure 2) that supplies power to the electric motor 5, and a brake system 100 that brakes the front wheel 3 and the rear wheel 4.

[0015] The electric motor 5 is an electric motor (e.g., an AC motor, a brushless DC motor, a synchronous motor, an induction motor, etc.) that receives power from the power supply unit to generate rotational torque, and uses that rotational torque to drive the rear wheels 4 via a power transmission mechanism (not shown) including a transmission. The electric motor 5 can also function as a generator and can generate electricity using the rotational force of the rear wheels 4. Alternatively, the electric motor may be configured such that the rotation shaft of the electric motor 5 and the rotation shaft of the rear wheels 4 are directly connected to drive the rear wheels 4 (e.g., a wheel-in motor).

[0016] The power supply unit 6 includes a power storage device (e.g., a storage battery, a capacitor, etc., not shown) that can temporarily store the input power within a predetermined capacity range and supply the stored power to the electric motor 5. The power supply unit 6 can function as a drive source of the motorcycle 10 by controlling the rotational torque acting as an accelerating force for accelerating the rotation of the electric motor 5 by controlling the power supplied from the power storage device to the electric motor 5. Further, when the power supply unit 6 functions as a generator by rotating the rotating shaft of the electric motor 5 by the rotational force of the rear wheel 4, the power supply unit 6 controls the power for charging, for example, the power storage device that becomes an electric load for the electric motor 5, thereby controlling the power generated by the electric motor 5 and controlling the regenerative torque that occurs due to power generation and acts as a rotational resistance on the rotation mechanism of the electric motor 5. The regenerative torque acts as a regenerative braking force generated on the rear wheel 4 by the braking system 100 described later.

[0017] As described above, the motorcycle 10 of the present embodiment is a rear-wheel drive saddle-type vehicle in which the rear wheel 4 is driven by an electric motor 5 that operates by receiving power supply from the power supply unit 6.

[0018] Note that the power supply unit 6 may be configured to supply power to the electric motor 5 via a power converter (e.g., an inverter, a voltage converter, etc.) from the power supply unit 6, or may be configured to supply power to the electric motor 5 from the power supply unit without passing through a power converter. Further, the power supply unit may include, for example, a power generation device (e.g., a fuel cell, a power generation device driven by an internal combustion engine to generate power, etc.) together with the power storage device, and may be configured to supply power to the electric motor 5 from the power storage device and the power generation device, or may be configured to include an internal combustion engine as a drive source of the rear wheel, for example.

[0019] <Regarding the braking system> As shown in FIGS. 1 to 3, the braking system 100 includes one operator 11 operated by the rider of the motorcycle 10, a front-wheel braking unit 20 that brakes the front wheel 3, a rear-wheel braking unit 40 that brakes the rear wheel 4, and a control device (ECU) 60 (see FIG. 4) that controls the braking force for braking the front wheel 3 and the rear wheel 4.

[0020] The operating element 11 is configured as a brake lever provided on the handle 2 and is operated by the rider's hand. A master cylinder 23 to which the movement of the operating element 11 is transmitted is provided on the operating element 11. The master cylinder 23 and the front-wheel braking unit 20 are connected by a brake fluid pipe 25a filled with brake fluid, and the operating element 11 is hydraulically connected to the front-wheel braking unit 20. Hydraulic pressure corresponding to the operation of the operating element 11 by the rider is generated from the master cylinder 23 and transmitted to the front-wheel braking unit 20 via the brake fluid pipe 25a.

[0021] The front-wheel braking unit 20 includes a friction-type front-wheel braking mechanism 21a that applies a frictional force to the front wheel 3 to generate a frictional braking force. The friction-type front-wheel braking mechanism 21a includes a friction application device 22a, a master cylinder 23, a reservoir 24a, liquid paths 25a to 25e, a wheel cylinder 27a, and a hydraulic pressure adjustment unit 30.

[0022] The friction-type front-wheel braking mechanism 21a presses a friction material (not shown) of the friction application device 22a held by the body 1 against a disk rotor 3a that rotates with the front wheel 3, and applies a frictional force corresponding to the operation amount of the operating element 11 to the front wheel 3, thereby generating and increasing the frictional braking force acting on the front wheel 3. On the other hand, the friction material (not shown) is separated from the disk rotor 3a, and the frictional force applied to the front wheel 3 is decreased and eliminated, thereby decreasing and eliminating the frictional braking force acting on the front wheel 3.

[0023] The friction-generating device 22a is hydraulically connected to the operator 11 and contains a wheel cylinder 27a to which the hydraulic pressure of brake fluid generated by the master cylinder 23 is input in response to the motion transmitted from the operator 11. The friction-generating device 22a is configured such that when the hydraulic pressure of the brake fluid inside the wheel cylinder 27a increases, the friction material is pressed against the disc rotor 3a in accordance with the increase in hydraulic pressure, while when the hydraulic pressure of the brake fluid inside the wheel cylinder 27a decreases, the friction material is moved away from the disc rotor 3a in accordance with the decrease in hydraulic pressure. In this way, the friction-generating device 22a generates, increases, decreases, and eliminates friction force on the disc rotor 3a in accordance with the amount of operation of the operator 11, thereby applying braking force to the front wheel 3. Note that the friction-generating device 22a may have other structures. For example, the friction-generating device 22a may be configured to press the friction material of the brake shoe held in the body 1 against the brake drum which rotates together with the front wheel 3, thereby generating friction force in accordance with the amount of operation of the operator 11.

[0024] The friction-type front wheel braking mechanism 21a includes a master cylinder 23 to which the motion of the operator 11 is transmitted, a reservoir 24a attached to the master cylinder 23, a wheel cylinder 27a built into the friction-applying device 22a and communicating with the master cylinder 23 via fluid passages 25a to 25e filled with brake fluid, a brake fluid pipe 25a which forms part of the fluid passages 25a to 25e and has one end connected to the master cylinder 23, a brake fluid pipe 25b which forms part of the fluid passages 25a to 25e and has one end connected to the wheel cylinder 27a, and a hydraulic pressure adjustment unit 30 connected to the other end of the brake fluid pipe 25a and the other end of the brake fluid pipe 25b. Note that the brake fluid pipe 25a may not be used and the hydraulic pressure adjustment unit 30 may be directly connected to the master cylinder 23, or the brake fluid pipe 25b may not be used and the hydraulic pressure adjustment unit 30 may be directly connected to the wheel cylinder 27a. Furthermore, the hydraulic pressure adjustment unit 30 may be integrated into a single unit with the master cylinder 23 or the wheel cylinder 27a.

[0025] As shown in Figures 2 and 3, the hydraulic pressure adjustment unit 30 includes a base body 31. The base body 31 is provided with a master cylinder port MP to which a brake fluid pipe 25a is connected and hydraulic pressure from the master cylinder 23 is input, and a wheel cylinder port WP to which a brake fluid pipe 25b is connected and hydraulic pressure is output to the wheel cylinder 27a. Inside the base body 31, an internal fluid passage is formed connecting the master cylinder port MP and the wheel cylinder port WP. The internal fluid passage includes a main fluid passage 25c connecting the master cylinder port MP and the wheel cylinder port WP, and a secondary fluid passage 25d that bypasses the main fluid passage 25c.

[0026] A suction valve 32 is provided in the middle of the main fluid passage 25c. The upstream end of the secondary fluid passage 25d is connected to the part of the main fluid passage 25c that is closer to the wheel cylinder port WP than the suction valve 32, and the downstream end of the secondary fluid passage 25d is connected to the main fluid passage 25c that is closer to the master cylinder port MP than the suction valve 32. The secondary fluid passage 25d is also provided with, in order from the upstream side, a release valve 33, an accumulator 34 for storing brake fluid, and a pump 35a.

[0027] Pump 35a is driven by motor 36. The filling valve 32, release valve 33, accumulator 34, pump 35a, and motor 36 are assembled on a base 31. A housing 37 for housing at least a portion of the control device 60 is attached to the base 31.

[0028] The suction valve 32 is a solenoid valve that, for example, switches the flow of brake fluid at its installation location from open to closed when the control device 60 switches from a non-energized state to an energized state. The release valve 33 is a solenoid valve that, for example, switches the flow of brake fluid toward the pump 35a via its installation location from closed to open when the control device 60 switches from a non-energized state to an energized state.

[0029] In the hydraulic pressure adjustment unit 30, the loading valve 32 and the release valve 33 are controlled to be energized. This causes the loading valve 32 to close, blocking the fluid passage that supplies brake fluid pressure from the master cylinder 23 to the wheel cylinder 27a, while the release valve 33 opens, creating a fluid passage through which brake fluid pressure moves from the wheel cylinder 27a to the accumulator 34 of the sub-fluid passage 25d. As a result, the brake fluid pressure in the wheel cylinder 27a is released to the accumulator 34, reducing the brake fluid pressure in the wheel cylinder 27a. Furthermore, in the hydraulic pressure adjustment unit 30, the pump 35a can be driven while the switching valve 38a (described later) is controlled to be de-energized, allowing the brake fluid pressure in the accumulator 34 to be returned to the master cylinder 23 and reservoir 24a.

[0030] Furthermore, the base 31 has an internal fluid passage, which is a pressure-boosting fluid passage 25e connecting the accumulator 34 and the pump 35a in the sub-fluid passage 25d, on the master cylinder port MP side of the main fluid passage 25c and the downstream end of the sub-fluid passage 25d. A switching valve 38a is provided between the junction of the main fluid passage 25c and the pressure-boosting fluid passage 25e and the junction with the downstream end of the sub-fluid passage 25d, and a pressure-boosting valve 39 is provided in the middle of the pressure-boosting fluid passage 25e.

[0031] The switching valve 38a is a solenoid valve that, for example, switches the flow of brake fluid at its installation location from open to closed when the control device 60 changes from a non-energized state to an energized state. The pressure boosting valve 39 is a solenoid valve that, for example, switches the flow of brake fluid toward the pump 35 via its installation location from closed to open when the control device 60 changes from a non-energized state to an energized state.

[0032] In the hydraulic pressure adjustment unit 30, the filling valve 32 and the release valve 33 are controlled to be de-energized, and the switching valve 38a and the pressure boosting valve 39 are controlled to be energized. As a result, the release valve 33 and the switching valve 38a are closed, blocking the fluid passage through which the hydraulic pressure of brake fluid returns from the master cylinder 23 to the wheel cylinder 27a via these valves. At the same time, the filling valve 32 and the pressure boosting valve 39 are opened, forming a fluid passage through which the hydraulic pressure of brake fluid is transferred from the reservoir 24a to the wheel cylinder 27a via these valves and the pump 35a. When the pump 35a is controlled to be driven, the hydraulic pressure of brake fluid is transferred from the reservoir 24a to the wheel cylinder 27a, increasing the hydraulic pressure in the wheel cylinder 27a. The hydraulic pressure adjustment unit 30 increases the hydraulic pressure of the wheel cylinder 27a using the pump 35a, thereby making the hydraulic pressure of the wheel cylinder 27a higher than the hydraulic pressure corresponding to the amount of operation of the control element 11 by the rider's operation.

[0033] In the hydraulic pressure adjustment unit 30, a first brake fluid pressure sensor 82 is provided in the region of the main fluid passage 25c on the master cylinder 23 side of the switching valve 38a to detect the fluid pressure of the brake fluid in the master cylinder 23, and a second brake fluid pressure sensor 83 is provided in the region of the main fluid passage 25c on the wheel cylinder 27a side of the filling valve 32 to detect the fluid pressure of the brake fluid in the wheel cylinder 27a.

[0034] The friction-applying device 22a, master cylinder 23, reservoir 24a, fluid passage 25, wheel cylinder 27a, and hydraulic pressure adjustment unit 30 correspond to the friction-type front wheel braking mechanism of the present invention, which brakes the front wheels with a frictional force corresponding to the hydraulic pressure.

[0035] The rear wheel braking unit 40 includes a friction-type rear wheel braking mechanism 21b that applies frictional force to the rear wheels 4 to generate frictional braking force, and a regenerative braking mechanism that generates regenerative braking force to the rear wheels 4. The friction-type rear wheel braking mechanism 21b includes a friction-applying device 22b, a reservoir 24b, fluid passages 26a to 26e, a wheel cylinder 27b, and a hydraulic pressure adjustment unit 30, while the regenerative braking mechanism includes an electric motor 5 that functions as a generator.

[0036] The friction-type rear wheel braking mechanism 21b generates and increases frictional braking force acting on the rear wheel 4 by pressing the friction material (not shown) of the friction-applying device 22b, which is held in the body 1, against the disc rotor 4a, which rotates together with the rear wheel 4, and applying frictional force to the rear wheel 4 in accordance with the control of the pump 35b and relief valve 38b, which will be described later, acting as actuators. On the other hand, by moving the friction material (not shown) away from the disc rotor 4a and reducing and eliminating the frictional force applied to the rear wheel 4 in accordance with the control of the actuator, the frictional braking force acting on the rear wheel 4 is reduced and eliminated.

[0037] The friction-applying device 22b is not hydraulically connected to the operator 11, and incorporates a wheel cylinder 27b to which the hydraulic pressure of the brake fluid, which is generated and increased in accordance with the control of the pump 35b acting as an actuator, is input. The friction-applying device 22b is configured such that as the hydraulic pressure of the brake fluid inside the wheel cylinder 27b increases, the friction material is pressed against the disc rotor 4a in accordance with the increase in hydraulic pressure, while the hydraulic pressure of the brake fluid is released from the wheel cylinder 27b in accordance with the control of the relief valve 38b, and as the hydraulic pressure of the brake fluid inside the wheel cylinder 27b decreases in accordance with the control of the relief valve 38b, the friction material is moved away from the disc rotor 4a in accordance with the decrease in hydraulic pressure. In this way, the friction-applying device 22b generates, increases, decreases, and eliminates friction force on the disc rotor 4a in accordance with the control of the pump 35b acting as an actuator, regardless of the amount of operation of the operator 11, thereby applying braking force to the rear wheel 4. Note that the friction-applying device 22b may have other structures. For example, the friction-applying device 22b may be configured to press the friction material of the brake shoe held by the body 1 against the brake drum which rotates together with the rear wheel 4, thereby generating a frictional force in accordance with the control of the actuator.

[0038] The friction-type rear wheel braking mechanism 21b includes a reservoir 24b for storing brake fluid, a wheel cylinder 27b built into the friction-applying device 22b, brake fluid pipes 26a and 26e which form part of the fluid passages 26a to 26e into which brake fluid is filled, with one end connected to the reservoir 24b, a brake fluid pipe 26b which forms part of the fluid passages 26a to 26e, with one end connected to the wheel cylinder 27b, and a hydraulic pressure adjustment unit 30 connected to the other end of brake fluid pipe 26a and the other end of brake fluid pipe 26b. Note that the brake fluid pipes 26a and 26e may be omitted, and the hydraulic pressure adjustment unit 30 may be directly connected to the reservoir 24b, or the brake fluid pipe 26b may be omitted, and the hydraulic pressure adjustment unit 30 may be directly connected to the wheel cylinder 27b. Furthermore, the hydraulic pressure adjustment unit 30 may be unitized together with the reservoir 24b or the wheel cylinder 27b.

[0039] As shown in Figures 2 and 3, the base body 31 described above is provided with a release port RP to which the brake fluid pipe 26a is connected, a wheel cylinder port WP to which the brake fluid pipe 26b is connected, and an input port IP to which the brake fluid pipe 26e is connected. Furthermore, an internal fluid passage is formed inside the base body 31 that connects the release port RP, the wheel cylinder port WP, and the input port IP. The internal fluid passage consists of a main fluid passage 26c that connects the release port RP and the wheel cylinder port WP, and a secondary fluid passage 26d that branches off from the main fluid passage 26c and connects the main fluid passage 26c and the input port IP.

[0040] A relief valve 38b is provided in the middle of the main fluid passage 26c. The upstream end of the secondary fluid passage 26d is connected to the input port IP, and the downstream end of the secondary fluid passage 26d is connected to the main fluid passage 26c between the relief valve 38b and the wheel cylinder port WP. A pump 35b is provided in the middle of the secondary fluid passage 26d.

[0041] Pump 35b is driven by the same motor 36 as pump 35a described above. Pump 35b and relief valve 38b are assembled to the base 31. Alternatively, pump 35b on the rear wheel 4 side and pump 35a on the front wheel 3 side may each be driven by their own dedicated motors.

[0042] The relief valve 38b is a solenoid valve that, for example, switches the flow of brake fluid at its installation location from open to closed when the control device 60 changes from a non-energized state to an energized state.

[0043] In the hydraulic pressure adjustment unit 30, the relief valve 38b is controlled to be energized, which closes the relief valve 38b and blocks the fluid passage through which the brake fluid pressure is released from the wheel cylinder 27b to the reservoir 24b. This creates a fluid passage through which the brake fluid pressure is moved from the reservoir 24b to the wheel cylinder 27b via the sub-fluid passage 26d and the pump 35b. As a result, the pump 35b drives the brake fluid pressure from the reservoir 24b to the wheel cylinder 27a, increasing the brake fluid pressure in the wheel cylinder 27b.

[0044] Furthermore, when the relief valve 38b is controlled to be de-energized, the relief valve 38b is opened, forming a fluid passage through which the brake fluid pressure is released from the wheel cylinder 27b to the reservoir 24b. As a result, the brake fluid pressure in the wheel cylinder 27b is released to the reservoir 24b, and the brake fluid pressure in the wheel cylinder 27b decreases.

[0045] As a result, the friction-applying device 22b is not connected to the operator 11 by hydraulic pressure, and the actuator (pump 35b and relief valve 38b) and the control device 60 are connected by an electrical control signal, i.e., a so-called by-wire system. This allows the hydraulic pressure of the wheel cylinder 27b of the friction-applying device 22b to be increased and decreased in accordance with the control of the pump 35b and relief valve 38b acting as actuators, thereby generating, increasing, decreasing, and eliminating the friction force that the friction-applying device 22b applies to the rear wheel 4. The friction-applying device 22b, reservoir 24b, fluid passages 26a to 26e, wheel cylinder 27b, and hydraulic pressure adjustment unit 30 correspond to a by-wire friction-type rear wheel braking mechanism that brakes the rear wheel 4 with a friction force corresponding to the control of the actuator of the present invention.

[0046] The friction-type rear wheel braking mechanism 21b includes an electric motor 5 as a regenerative braking mechanism. The electric motor 5 is configured to apply regenerative torque generated when it operates as a generator due to the rotational force of the rear wheel 4 to the rear wheel 4, thereby generating a regenerative braking force that brakes the rear wheel 4 with this regenerative torque. When the rotation shaft of the electric motor 5 is rotated by the rotational force of the rear wheel 4, an induced electromotive force is generated, and a regenerative torque corresponding to the current flowing to the energy storage device due to the induced electromotive force is generated in the opposite direction to the rotation of the rear wheel 4, acting to decelerate the rotation of the rear wheel 4. By utilizing this action, the electric motor 5 functions as part of the brake system 100, enabling the rear wheel 4 to be braked without the need for a friction-type braking mechanism that generates friction braking force. The electric motor 5, which functions as a generator, corresponds to the regenerative braking mechanism that generates regenerative braking force on the rear wheel according to the present invention.

[0047] As shown in Figure 4, the control device 60 includes a first control unit 61 that controls the operation of the inlet valve 32, release valve 33, switching valve 38a, pressure boosting valve 39, and motor 36 of the front wheel braking unit 20; a second control unit 62 that controls the operation of the relief valve 38b and the electric motor 5 as a generator of the rear wheel braking unit 40; an acquisition unit 63 that acquires abnormal information regarding abnormalities in the front wheel braking unit 20; and an execution unit 64 that controls the relief valve 38b and pump 35b as actuators based on the abnormal information. The first control unit 61 and the second control unit 62 may be combined into one unit or divided into multiple units. Parts or all of each of the first control unit 61 and the second control unit 62 may be composed of, for example, a microcontroller, a microprocessor unit, etc., or may be composed of updatable firmware, etc., or may be a program module executed by commands from a CPU, etc.

[0048] The control device 60 receives output signals from, for example, the front wheel rotation speed sensor 81, the first brake fluid pressure sensor 82, the second brake fluid pressure sensor 83, the rear wheel rotation speed sensor 91, the remaining battery charge sensor 92, and the surrounding environment sensor 93, either via wired or wireless input. Output signals from other sensors may also be input to the control device 60. Based on these sensor output signals, the control device 60 derives target braking forces to be generated for the front wheel 3 and the rear wheel 4, respectively. The first control unit 61 outputs command signals corresponding to the target braking force to be generated for the front wheel 3 to the fill valve 32, the release valve 33, the switching valve 38a, the pressure boosting valve 39, and the motor 36 driver, either via wired or wireless input. The second control unit 62 also outputs command signals corresponding to the target braking force to be generated for the rear wheel 4 to the relief valve 38b, the motor 36 driver, and the control device that controls the power to charge the battery.

[0049] The front wheel rotation speed sensor 81 detects the rotation speed of the front wheel 3. The front wheel rotation speed sensor 81 is held, for example, by the fuselage 1. The front wheel rotation speed sensor 81 may also detect other physical quantities that can be substantially converted to the rotation speed of the front wheel 3.

[0050] The first brake fluid pressure sensor 82 detects the fluid pressure of the brake fluid in the master cylinder 23. The first brake fluid pressure sensor 82 is located in the area of ​​the main fluid passage 25c on the front wheel 3 side that is closer to the master cylinder 23 than the switching valve 38a (see Figure 2). The first brake fluid pressure sensor 82 may also detect other physical quantities that can be substantially converted into the fluid pressure of the brake fluid in the master cylinder 23 (for example, the amount of operation of the operator 11, the displacement of the operator 11, the displacement of the piston in the master cylinder 23, etc.).

[0051] The second brake fluid pressure sensor 83 detects the fluid pressure of the brake fluid in the wheel cylinder 27a. The second brake fluid pressure sensor 83 is located in the area of ​​the main fluid passage 25c on the front wheel 3 side that is closer to the wheel cylinder 27a than the suction valve 32 (see Figure 2). The second brake fluid pressure sensor 83 may also detect other physical quantities that can be substantially converted into the fluid pressure of the brake fluid in the wheel cylinder 27a (for example, the displacement of the friction material in the friction device 22a).

[0052] The rear wheel rotation speed sensor 91 detects the rotation speed of the rear wheel 4. The rear wheel rotation speed sensor 91 is held, for example, by the fuselage 1. The rear wheel rotation speed sensor 91 may also detect other physical quantities that are substantially convertible to the rotation speed of the rear wheel 4.

[0053] The remaining energy sensor 92 detects the remaining amount of energy stored in the energy storage device provided by the power supply unit 6. The remaining energy sensor 92 can be any type of sensor that detects a physical quantity that reflects the amount of energy stored in the energy storage device or the available capacity that can store power in the energy storage device (for example, the voltage value of the battery provided in the energy storage device, the current value input and output to the energy storage device, etc.).

[0054] The surrounding environment sensor 93 detects the environment around the motorcycle 10 (for example, the road surface conditions in the direction of travel of the motorcycle 10, other vehicles, etc.). The surrounding environment sensor 93 can be any device that detects information reflecting the environment around the motorcycle 10 (for example, a camera, ultrasonic sensor, radar device, external communication device, etc.).

[0055] In this embodiment, the hydraulic pressure adjustment unit 30 is configured to include a first brake fluid pressure sensor 82 for detecting the hydraulic pressure of the brake fluid in the master cylinder 23, and a second brake fluid pressure sensor 83 for detecting the hydraulic pressure of the brake fluid in the wheel cylinder 27a. However, the hydraulic pressure adjustment unit 30 may also be configured to include only one of the first brake fluid pressure sensor 82 or the second brake fluid pressure sensor 83. For example, the hydraulic pressure adjustment unit 30 may be configured to include only the first brake fluid pressure sensor 82 and estimate the hydraulic pressure of the brake fluid in the wheel cylinder 27a based on the hydraulic pressure detected by the first brake fluid pressure sensor 82 or other physical quantities that can be substantially converted to the hydraulic pressure of the brake fluid in the master cylinder 23. For example, the hydraulic pressure adjustment unit 30 may be configured to include only the second brake fluid pressure sensor 83 and estimate the hydraulic pressure of the brake fluid in the master cylinder 23 based on the hydraulic pressure detected by the second brake fluid pressure sensor 83 or other physical quantities that can be substantially converted to the hydraulic pressure of the brake fluid in the wheel cylinder 27a. Alternatively, the hydraulic pressure adjustment unit 30 may not include both the first brake fluid pressure sensor 82 and the second brake fluid pressure sensor 83, and may be configured to estimate the hydraulic pressure of the brake fluid in the wheel cylinder 27a based on other physical quantities that can be substantially converted to the hydraulic pressure of the brake fluid in the master cylinder 23, and to estimate the hydraulic pressure of the brake fluid in the master cylinder 23 based on other physical quantities that can be substantially converted to the hydraulic pressure of the brake fluid in the wheel cylinder 27a.

[0056] The first control unit 61 and the second control unit 62 are housed within the housing 37 of the hydraulic pressure adjustment unit 30 and are unitized together with the hydraulic pressure adjustment mechanism (e.g., a suction valve 32, a release valve 33, a motor 36, a switching valve 38a, a pressure boosting valve 39, etc.). This configuration allows for the common sealing structure of the first control unit 61 and the second control unit 62, thereby improving the cost-effectiveness of the brake system 100.

[0057] The second control unit 62 may be integrated into a single unit with the electric motor 5 and the power supply unit 6. This configuration allows for the separate management of the front wheel braking unit 20 and the rear wheel braking unit 40, thereby improving the maintainability and retrofitability of the brake system 100.

[0058] When the motorcycle 10 is stopped, or when the motorcycle 10 is running without slippage exceeding a standard value in the front wheel 3 and rear wheel 4, and the rider operates the control element 11, that is, during normal braking, the first control unit 61 controls the load valve 32, release valve 33, switching valve 38a and pressure boosting valve 39 to a non-energized state, and also controls the motor 36 to a non-driving state. In this state, when the rider operates the control element 11, the piston (not shown) of the master cylinder 23 is pushed in according to the movement of the control element 11, increasing the hydraulic pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction device 22a is pressed against the disc rotor 3a, generating or increasing the frictional braking force applied to the front wheel 3. Furthermore, when the rider releases the operator 11, the piston (not shown) of the master cylinder 23 is returned in accordance with the movement of the operator 11, reducing the hydraulic pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction device 22a is separated from the disc rotor 3a, reducing or eliminating the frictional braking force applied to the front wheel 3. In other words, in the front wheel braking unit 20, during normal braking, the frictional braking force applied to the front wheel 3 by the friction device 22a changes in accordance with the change in hydraulic pressure of the brake fluid in the master cylinder 23 in accordance with the movement of the operator 11.

[0059] When the operator 11 is operated by the rider, the control device 60 performs linked braking control, which includes applying frictional braking force to the front wheel 3 by the front wheel braking unit 20, and applying regenerative braking force to the rear wheel 4 by the rear wheel braking unit 40.

[0060] In linked brake control, the control device 60 acquires, for example, the braking force requested by the rider based on the amount of operation of the operator 11 (hereinafter sometimes referred to as the requested braking force), driving information regarding the driving state of the motorcycle 10 (for example, speed, body tilt, etc.), and capacity information regarding the remaining capacity that can be stored in the power storage device of the power supply unit 6. Then, based on the driving information and capacity information, it acquires the regenerative braking force that can be generated by the electric motor 5, which is a regenerative braking mechanism, and compares this regenerative braking force with the requested braking force. If it is determined that the requested braking force exceeds the regenerative braking force, the control device 60 performs control to generate the amount of braking force that the requested braking force exceeds the regenerative braking force as friction braking force by the friction-type front wheel braking mechanism 21a, and also performs control to generate regenerative braking force by the electric motor 5.

[0061] Furthermore, in linked brake control, the target braking force of the front wheel braking unit 20 and the target braking force of the rear wheel braking unit 40 are obtained, respectively, when the required braking force is distributed in a predetermined ratio (for example, the ratio of braking force at the front wheel 3 and braking force at the rear wheel 4 that does not reduce the driving stability of the motorcycle 10) based on the driving state of the motorcycle 10.

[0062] The first control unit 61 then acquires information regarding the regenerative braking force that can be generated based on the power storage status of the power supply unit 6, and compares the target braking force of the rear wheel braking unit 40 with the regenerative braking force that can be generated by the rear wheel braking unit 40. If the target braking force of the rear wheel braking unit 40 is within the range of the regenerative braking force that can be generated by the rear wheel braking unit 40, the first control unit 61 performs friction braking force control to generate the target braking force of the front wheel braking unit 20 as the friction braking force of the friction braking mechanism. On the other hand, if the target braking force of the rear wheel braking unit 40 exceeds the range of regenerative braking force that can be generated by the rear wheel braking unit 40, the first control unit 61 performs friction braking force control so that, in addition to the target braking force of the front wheel braking unit 20, it generates a braking force equal to the difference between the target braking force of the rear wheel braking unit 40 and the regenerative braking force that can be generated by the rear wheel braking unit 40 (hereinafter sometimes referred to as insufficient braking force) as friction braking force of the friction-type front wheel braking mechanism 21a.

[0063] Specifically, in friction braking force control, for example, the loading valve 32, release valve 33, and switching valve 38a are controlled to be energized, the pressure boosting valve 39 is controlled to be de-energized, and the motor 36 is controlled to be driven. Through such control, the hydraulic pressure of the brake fluid supplied from the master cylinder 23 to the wheel cylinder 27a is released within a predetermined range by the movement of the operator 11, reducing the master cylinder 23 to a predetermined value, and generating the target braking force of the front wheel braking unit 20 and the aforementioned insufficient braking force as friction braking force of the friction applying device 22a. In other words, in the front wheel braking unit 20, when interlocking brake control is executed, friction braking force is generated by the friction applying device 22a in accordance with the movement of the operator 11 and applied to the front wheel 3.

[0064] In response to this, the second control unit 62 controls the power to charge the energy storage device within a range that can be generated based on the driving conditions of the motorcycle 10 (e.g., speed, inclination, etc.) and the energy storage status, and within a range up to the target braking force of the rear wheel braking unit 40, thereby controlling the regenerative braking force to be generated by the regenerative braking mechanism.

[0065] Furthermore, in friction braking control, when it is necessary to increase the friction braking force applied to the front wheel 3, for example, when the regenerative braking force that can be generated by the rear wheel braking unit 40 decreases during the execution of friction braking control, the first control unit 61 controls the engagement valve 32 and release valve 33 to a de-energized state, controls the switching valve 38a and pressure boosting valve 39 to an energized state, and drives the motor 36 with a drive amount corresponding to the output signal of the second brake fluid pressure sensor 83. By increasing the fluid pressure of the brake fluid in the wheel cylinder 27a through such control, the friction braking force provided by the friction-applying device 22a is increased, thereby compensating for the decrease in regenerative braking force. In other words, in the front wheel braking unit 20, when interlocking brake control is executed, the friction braking force applied to the front wheel 3 by the friction-applying device 22a increases regardless of the movement of the operator 11.

[0066] Furthermore, in friction braking control, when it is necessary to reduce the friction braking force applied to the front wheel 3, for example, when the regenerative braking force generated by the rear wheel braking unit 40 increases during the execution of friction braking control, the first control unit 61 controls the engagement valve 32 and release valve 33 to an energized state, and also drives the motor 36 with a drive amount corresponding to the output signals of the first brake fluid pressure sensor 82 and the second brake fluid pressure sensor 83. By reducing the fluid pressure of the brake fluid in the wheel cylinder 27a through such control, the friction braking force applied by the friction device 22a is reduced. In other words, in the front wheel braking unit 20, when interlocking brake control is executed, the friction braking force applied to the front wheel 3 by the friction device 22a is reduced regardless of the movement of the operator 11.

[0067] These controls ensure that the total braking force generated by the brake system 100, i.e., the sum of the frictional braking force from the front wheel braking unit 20 and the regenerative braking force from the rear wheel braking unit 40, equals the braking force required by the rider.

[0068] The control device 60 may perform the lock control operation, slip control operation, stop support control operation, and emergency braking control operation described later while performing the interlocking brake control.

[0069] If the motorcycle 10 is traveling with the front wheel 3 and rear wheel 4 locked or in a state where locking is likely to occur, the control device 60 performs a lock control operation to suppress locking. The lock control operation includes the operation of anti-lock brake control for each wheel. When performing the lock control operation, the control device 60 may control other systems mounted on the motorcycle 10 in addition to the brake system 100. The control device 60 performs the lock control operation regardless of the movement of the operator 11.

[0070] Furthermore, the locking of the front wheel 3 and rear wheel 4 of the motorcycle 10, and the possibility of locking, can be determined by a well-known method using the output signals of the front wheel rotation speed sensor 81 and the rear wheel rotation speed sensor 91.

[0071] When performing a lock control operation, if it is necessary to reduce the frictional braking force applied to the front wheel 3, the first control unit 61 controls the engagement valve 32 and release valve 33 to an energized state, and also drives the motor 36 with a drive amount corresponding to the output signals of the first brake fluid pressure sensor 82 and the second brake fluid pressure sensor 83. Such control reduces the hydraulic pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction device 22a is separated from the disc rotor 3a. In other words, in the front wheel braking unit 20, when performing a lock control operation, the frictional braking force applied to the front wheel 3 by the friction device 22a changes regardless of the movement of the operator 11 due to the control of the engagement valve 32, release valve 33, and motor 36 by the control device 60. Alternatively, instead of the output signals of the first brake fluid pressure sensor 82 and the second brake fluid pressure sensor 83, command signals to the drivers of the engagement valve 32, release valve 33, and motor 36 transmitted by the first control unit 61 immediately before may be used.

[0072] When performing a lock control operation, if it is necessary to reduce the regenerative braking force applied to the rear wheel 4, the second control unit 62 reduces the power supplied to charge the energy storage device of the power supply unit 6. This control reduces the electrical load on the electric motor 5, which functions as a generator, thereby reducing the regenerative braking force generated by the electric motor 5. In other words, in the rear wheel braking unit 40, when performing a lock control operation, the regenerative braking force applied to the rear wheel 4 by the electric motor 5 changes regardless of the movement of the operator 11 by controlling the power supplied to charge the energy storage device.

[0073] When the lock control operation is performed, if the regenerative braking force applied to the rear wheel 4 causes the rear wheel 4 to lock or there is a possibility of locking, the first control unit 61 controls the ignition valve 32 and the release valve 33 to a de-energized state, controls the switching valve 38a and the pressure boosting valve 39 to an energized state, and drives the motor 36 with a drive amount corresponding to the output signal of the second brake fluid pressure sensor 83. Such control increases the fluid pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction device 22a is pressed against the disc rotor 3a. In other words, in the front wheel braking unit 20, when the lock control operation is performed, the friction braking force applied to the front wheel 3 by the friction device 22a is generated or increased by the control device 60's control of the ignition valve 32, release valve 33, switching valve 38a, pressure boosting valve 39, and motor 36, regardless of the movement of the operator 11. This allows the regenerative braking force to be compensated for by the increased frictional braking force at the front wheels when the rear four wheels lock up, thus reducing the regenerative braking force.

[0074] If the motorcycle 10 is traveling in a state where the front wheel 3 and rear wheel 4 are slipping beyond a standard value or where there is a possibility of slipping, the control device 60 will perform a slip control operation to suppress the slip. Slip control operations include, for example, operations that perform anti-lock brake control on each wheel, operations that perform wheelspin suppression control on each wheel, and operations that perform sideslip suppression control on each wheel. When performing a slip control operation, the control device 60 may control other systems mounted on the motorcycle 10 in addition to the brake system 100. The control device 60 performs the slip control operation regardless of the movement of the operator 11.

[0075] Furthermore, the slippage occurring in the front wheel 3 and rear wheel 4 of the motorcycle 10, as well as the possibility of slippage, can be determined using a well-known method that utilizes the output signals of the front wheel rotation speed sensor 81 and the rear wheel rotation speed sensor 91.

[0076] When slip control is performed and it is necessary to reduce the frictional braking force applied to the front wheel 3, the first control unit 61 controls the engagement valve 32 and release valve 33 to an energized state, and also drives the motor 36 with a drive amount corresponding to the output signals of the first brake fluid pressure sensor 82 and the second brake fluid pressure sensor 83. Such control reduces the fluid pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction-applying device 22a is separated from the disc rotor 3a. In other words, in the front wheel braking unit 20, when slip control is performed, the frictional braking force applied to the front wheel 3 by the friction-applying device 22a changes regardless of the movement of the operator 11, due to the control of the engagement valve 32, release valve 33, and motor 36 by the control device 60. Alternatively, instead of the output signals from the first brake fluid pressure sensor 82 and the second brake fluid pressure sensor 83, the command signals transmitted by the first control unit 61 immediately beforehand to the drivers of the ignition valve 32, the release valve 33, and the motor 36 may be used.

[0077] When slip control is performed, if it is necessary to reduce the regenerative braking force applied to the rear wheels 4, the second control unit 62 reduces the power supplied to charge the energy storage device of the power supply unit 6. This control reduces the electrical load on the electric motor 5, which functions as a generator, thereby lowering the regenerative braking force generated by the electric motor 5. In other words, in the rear wheel braking unit 40, when slip control is performed, the regenerative braking force applied to the rear wheels 4 by the electric motor 5 changes regardless of the movement of the operator 11 by controlling the power supplied to charge the energy storage device.

[0078] When slip control is performed, if it is necessary to generate or increase the frictional braking force applied to the front wheel 3 (for example, when slip occurs in the rear wheel 4 due to regenerative braking force during cornering of the motorcycle 10, or when there is a possibility of slip), the first control unit 61 controls the load valve 32 and release valve 33 to a de-energized state, controls the switching valve 38a and pressure boosting valve 39 to an energized state, and drives the motor 36 with a drive amount corresponding to the output signal of the second brake fluid pressure sensor 83. Such control increases the fluid pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction device 22a is pressed against the disc rotor 3a. In other words, in the front wheel braking unit 20, when slip control operation is performed, the friction braking force applied to the front wheel 3 by the friction-applying device 22a is generated and increased independently of the movement of the operator 11 by the control device 60's control of the saturation valve 32, release valve 33, switching valve 38a, pressure boosting valve 39, and motor 36. This allows the reduction in regenerative braking force due to slip of the rear wheel 4 to be compensated for by the increase in friction braking force at the front wheel. Alternatively, instead of the output signal of the second brake fluid pressure sensor 83, the command signals to the drivers of the saturation valve 32, release valve 33, switching valve 38a, pressure boosting valve 39, and motor 36 transmitted by the first control unit 61 immediately before the output signal may be used.

[0079] When it is necessary to increase the regenerative braking force applied to the rear wheels 4 during lock control or slip control, the second control unit 62 increases the power supply to charge the energy storage device of the power supply unit 6. Such control increases the electrical load on the electric motor 5, which functions as a generator, thereby increasing the regenerative braking force generated by the electric motor 5. In other words, in the rear wheel braking unit 40, when slip control is performed, the regenerative braking force applied to the rear wheels 4 by the electric motor 5 changes regardless of the movement of the operator 11 by controlling the power supply to charge the energy storage device.

[0080] When the motorcycle 10 is coming to a stop, or when the motorcycle 10 is stopped and the rider is operating the control device 11, the control device 60 performs a stop support control operation to generate braking force on at least the front wheel 3 to assist in the transition to and maintenance of the motorcycle 10 in a stopped state. When performing the stop support control operation, the control device 60 may control other systems mounted on the motorcycle 10 in addition to the brake system 100. The stop support operation is released, for example, when it is determined that the rider's hand has been released from the control device 11 and the operation has ended.

[0081] When performing a stop support control operation, if it is necessary to increase the frictional force applied to the front wheel 3 (for example, when the braking force based on the amount of operation of the operator 11 is less than the braking force required to maintain the stopped state of the motorcycle 10), the first control unit 61 controls the loading valve 32 and the release valve 33 to a de-energized state, controls the switching valve 38a and the pressure boosting valve 39 to an energized state, and drives the motor 36 with a drive amount corresponding to the output signal of the second brake fluid pressure sensor 83. Such control increases the fluid pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction-applying device 22a is pressed against the disc rotor 3a. In other words, in the front wheel braking unit 20, when performing a stop support control operation, the frictional braking force applied to the front wheel 3 by the friction-applying device 22a changes regardless of the movement of the operator 11 due to the control of the loading valve 32, the release valve 33, the switching valve 38a, the pressure boosting valve 39, and the motor 36 by the control device 60. Alternatively, instead of the output signal from the second brake fluid pressure sensor 83, the command signals transmitted by the first control unit 61 immediately beforehand to the drivers of the ignition valve 32, release valve 33, switching valve 38a, pressure boosting valve 39, and motor 36 may be used. Furthermore, for example, when the stop support control operation is performed, the regenerative braking force applied to the rear wheels 4 may be increased.

[0082] Based on information regarding the state of the surrounding environment of the motorcycle 10 detected by the surrounding environment sensor 93, if it is necessary to urgently decelerate or stop the motorcycle 10, the control device 60 performs an emergency braking control operation that generates frictional braking force on at least the front wheel 3. When performing the emergency braking control operation, the control device 60 may control other systems mounted on the motorcycle 10 in addition to the brake system 100. Alternatively, the control device 60 may perform the above-described interlocking brake control to distribute the braking force necessary to urgently decelerate or stop the motorcycle 10 to the target braking force of the front wheel braking unit 20 and the target braking force of the rear wheel braking unit 40 to generate braking force.

[0083] When an emergency braking control operation is performed and it is necessary to increase the frictional braking force applied to the front wheel 3, the first control unit 61 controls the loading valve 32 and the release valve 33 to a de-energized state, controls the switching valve 38a and the pressure boosting valve 39 to an energized state, and drives the motor 36 with a drive amount corresponding to the output signal of the second brake fluid pressure sensor 83. Such control increases the fluid pressure of the brake fluid in the wheel cylinder 27a, and the friction material (not shown) of the friction-applying device 22a is pressed against the disc rotor 3a. In other words, in the front wheel braking unit 20, when an emergency braking control operation is performed, the frictional braking force applied to the front wheel 3 by the friction-applying device 22a changes regardless of the movement of the operator 11 due to the control of the loading valve 32, the release valve 33, the switching valve 38a, the pressure boosting valve 39, and the motor 36 by the control device 60. Alternatively, instead of the output signal from the second brake fluid pressure sensor 83, the command signals transmitted by the first control unit 61 immediately beforehand to the drivers of the suction valve 32, release valve 33, switching valve 38a, pressure boosting valve 39, and motor 36 may be used.

[0084] Furthermore, when an emergency braking control operation is performed and it is necessary to increase the regenerative braking force applied to the rear wheels 4, the second control unit 62 increases the power to charge the energy storage device of the power supply unit 6. Such control increases the electrical load on the electric motor 5, which functions as a generator, and increases the regenerative braking force generated by the electric motor 5. In other words, in the rear wheel braking unit 40, when a slip control operation is performed, the regenerative braking force applied to the rear wheels 4 by the electric motor 5 changes regardless of the movement of the operator 11, due to the control of the power to charge the energy storage device of the power supply unit 6 by the control device 60.

[0085] The control device 60 may be configured to distribute part or all of the target braking force of the front wheel braking unit 20 and the rear wheel braking unit 40 to the friction braking force of the friction-type rear wheel braking mechanism 21b in the above-mentioned interlocking brake control, lock control operation, slip control operation, stop support control operation, emergency braking control operation, etc.

[0086] The control device 60 includes an acquisition unit 63 that acquires abnormal information regarding the abnormality of the front wheel braking unit 20, and an execution unit 64 that controls the relief valve 38b and the pump 35b as actuators based on the abnormal information.

[0087] The acquisition unit 63 monitors, for example, the output of the rear wheel rotation speed sensor 91 and the remaining charge sensor 92, and determines at predetermined intervals whether the electric motor 5, which serves as the regenerative braking mechanism, can function as a generator to generate regenerative braking force based on the outputs of these sensors. If it is determined that the regenerative braking mechanism can generate regenerative braking force, it sets regenerative information indicating that regenerative braking force can be generated in the storage means of the control device 60 and continues monitoring and determination. On the other hand, if it is determined that regenerative braking force cannot be generated (for example, if the rotation speed of the rear wheels 4 is lower than the reference value for generating power, or if there is insufficient available capacity in the energy storage device), it sets regenerative information indicating that regenerative braking force cannot be generated in the storage means of the control device 60.

[0088] Furthermore, the acquisition unit 63 monitors, for example, the output history of the front wheel rotation speed sensor 81, the first brake fluid pressure sensor 82, and the second brake fluid pressure sensor 83, as well as the operation of the first control unit 61 and the second control unit 62, and determines at predetermined intervals whether or not the front wheel braking unit 20 is functioning normally. If it is determined that the front wheel braking unit 20 is functioning normally, it sets abnormality information indicating that there is no abnormality in the front wheel braking unit 20 into the storage means of the control device 60 and continues monitoring and determination. On the other hand, if it is determined that the front wheel braking unit 20 is not functioning properly (for example, if the actual braking force output by the front wheel braking unit 20 is less than the target braking force of the front wheel braking unit 20, or if the output values ​​of the first brake fluid pressure sensor 82 and the second brake fluid pressure sensor 83 fall below predetermined reference values ​​at a predetermined timing, and there is a risk that the braking force provided by the front wheel braking unit 20 will not meet the target braking force), then abnormal information indicating that there is an abnormality in the front wheel braking unit 20 is set in the storage means of the control device 60.

[0089] In response to this, if the execution unit 64 determines, based on the regenerative information set in the control device 60 storage means, that it is not possible to generate regenerative braking force, it operates the pump 35b and the relief valve 38b as actuators to perform control that generates, increases, decreases, and eliminates friction braking force by the friction-type rear wheel braking mechanism 21b based on, for example, the driving state of the motorcycle 10, the operating state of the control element 11, etc.

[0090] Furthermore, if the execution unit 64 determines that an abnormality has occurred in the front wheel braking unit 20 based on abnormality information set in the control device 60 storage means, it activates the pump 35b and the relief valve 38b as actuators to perform control that generates, increases, decreases, and eliminates friction braking force by the friction-type rear wheel braking mechanism 21b based on, for example, the driving state of the motorcycle 10, the operating state of the control element 11, etc.

[0091] As described above, the brake system 100 of this embodiment is a brake system for a rear-wheel drive motorcycle 10, and includes a front wheel braking unit 20 that brakes the front wheel 3 of the motorcycle 10, a rear wheel braking unit 40 that brakes the rear wheel 4 of the motorcycle 10, and an operating element 11 operated by the rider of the motorcycle 10. The front wheel braking unit 20 includes a friction-type front wheel braking mechanism 21a that is hydraulically connected to the operating element 11 and brakes the front wheel 3 with a frictional force corresponding to the hydraulic pressure. The rear wheel braking unit 40 includes a regenerative braking mechanism 5 that generates a regenerative braking force on the rear wheel 4 in accordance with the rotation of the rear wheel 4, and a drive-by-wire type friction-type rear wheel braking mechanism 21b that is not hydraulically connected to the operating element 11 and brakes the rear wheel 4 with a frictional force corresponding to the control of a rear-wheel side pump 35b and a relief valve 38b acting as actuators.

[0092] Furthermore, the brake system 100 of this embodiment is a brake system for a motorcycle 10 as a rear-wheel drive saddle-type vehicle, and comprises a front wheel braking unit 20 that brakes the front wheel 3 of the motorcycle 10, a rear wheel braking unit 40 that brakes the rear wheel 4 of the motorcycle 10, and an operating element 11 operated by the rider of the motorcycle 10. The front wheel braking unit 20 is equipped with a friction-type front wheel braking mechanism 21a (composed of a friction-applying device 22a, a master cylinder 23, a reservoir 24a, a fluid passage 25, a wheel cylinder 27a, a hydraulic pressure adjustment unit 30, a control device 60, etc.) that generates friction braking force only on the front wheel 3, and can generate friction braking force in accordance with the movement of the operating element 11 during normal braking, for example. The rear wheel braking unit 40 is equipped with an electric motor 5 that functions as a generator and generates regenerative torque that acts as regenerative braking force, as a regenerative braking mechanism that generates regenerative braking force on the rear wheel 4. Furthermore, the front wheel braking unit 20 is configured to increase and decrease the frictional braking force provided by the friction-type front wheel braking mechanism 21a (composed of a friction-applying device 22a, a master cylinder 23, a reservoir 24a, a fluid passage 25, a wheel cylinder 27a, a hydraulic pressure adjustment unit 30, etc.) regardless of the movement of the operator 11, for example, in linked brake control, lock control operation, slip control operation, stop support control operation, emergency brake control operation, etc., performed by the control device 60.

[0093] Furthermore, the brake system 100 of this embodiment is equipped with a single control element 11 common to both the front wheel braking unit 20 and the rear wheel braking unit 40. The control device 60 performs interlocking brake control, distributing the braking force requested by the rider, obtained based on the amount of operation of the control element 11, to the target braking force of the front wheel braking unit 20 and the target braking force of the rear wheel braking unit 40, thereby generating braking force from the front wheel braking mechanism and the rear wheel braking mechanism.

[0094] Furthermore, the brake system 100 of this embodiment is configured to include a single control element 11 common to both the front wheel braking section 20 and the rear wheel braking section 40, which is operated by the rider's hand.

[0095] In this embodiment, the brake system 100 is configured to include an operating element 11 that is operated by the rider's hand. However, the brake system may also be configured to include an operating element that is operated by something other than the rider's hand, such as the rider's foot.

[0096] <Regarding the effectiveness of the braking system> Conventionally, as a braking system for rear-wheel-drive saddle-type vehicles in which the rear wheels are driven by an electric motor, there are configurations that include a regenerative braking mechanism that applies regenerative torque generated by the rotation of the rear wheels to the rear wheels, thereby braking them, and a friction brake mechanism that generates frictional force on the front wheels in response to the rider's operation of the brake lever. In such a braking system, the regenerative braking mechanism functions as a generator by inputting rotational force to the shaft of the electric motor, and the regenerative torque generated during power generation brakes the wheels of the saddle-type vehicle. Therefore, for example, when the rotational speed of the rear wheel to which the electric motor is connected is low, or when the rotation of the rear wheel is stopped, or when the electric motor cannot generate power, the braking force that the regenerative braking mechanism can generate may be insufficient to meet the target value, or it may not be able to generate any braking force at all, which may make it impossible to stop the motorcycle from a moving state or to maintain a stopped state.

[0097] In contrast, the motorcycle 10 of this embodiment is a rear-wheel drive type saddle-type vehicle in which the rear wheel 4 is driven by an electric motor 5, and the brake system 100 of the motorcycle 10 is a brake system for a rear-wheel drive motorcycle 10 and includes a front wheel braking unit 20 that brakes the front wheel 3 of the motorcycle 10, a rear wheel braking unit 40 that brakes the rear wheel 4 of the motorcycle 10, and at least one operator 11 that is operated by the rider of the motorcycle 10, the front wheel braking unit 20 is operated by the operator 11 The rear wheel braking section 40 includes a friction-type front wheel braking mechanism 21a that is hydraulically connected to the rear wheel 3 and brakes the front wheel 3 with a frictional force corresponding to the hydraulic pressure, and a regenerative braking mechanism (electric motor 5) that generates a regenerative braking force on the rear wheel 4 in accordance with the rotation of the rear wheel 4, and a drive-by-wire friction-type rear wheel braking mechanism 21b that is not hydraulically connected to the operator 11 and brakes the rear wheel 4 with a frictional force corresponding to the control of the rear wheel side pump 35b and relief valve 38b, which are actuators that operate in response to the input of an electrical control signal.

[0098] With this configuration, the rear wheel braking unit 40 is equipped with a regenerative braking mechanism and is not hydraulically connected to the operator 11. It is equipped with a drive-by-wire friction-type rear wheel braking mechanism 21b that brakes the rear wheel 4 with a frictional force corresponding to the control of the rear wheel pump 35b and relief valve 38b. By controlling the pump 35b and relief valve 38b as actuators, a predetermined frictional force corresponding to that control can be applied to the rear wheel 4 by the friction-type rear wheel braking mechanism 21b, thereby generating braking force on the rear wheel 4. This increases the braking force that can be generated by the brake system 100 and improves the safety of the motorcycle 10 during braking. Furthermore, since the rear wheel braking unit 40 is equipped with a friction-type rear wheel braking mechanism 21b that is different from the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20, for example, even if a malfunction occurs in the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20 and the front wheel braking unit 20 is unable to brake the front wheel 3, the rear wheel braking unit 40 can still brake the rear wheel 4, thereby improving the safety of the motorcycle 10 during braking.

[0099] The friction-type rear wheel braking mechanism 21b of this embodiment includes a wheel cylinder 27b to which the hydraulic pressure of brake fluid is input, a friction-applying device 22b that applies a friction force to the rear wheel 4 in accordance with the hydraulic pressure of the wheel cylinder 27b, a pump 35b that moves brake fluid to the wheel cylinder 27b and increases the hydraulic pressure of the wheel cylinder 27b, and a relief valve 38b that releases brake fluid from the wheel cylinder 27b. When generating and increasing the friction force applied to the rear wheel 4, the pump 35b is driven as an actuator to move brake fluid to the wheel cylinder 27b and increase the hydraulic pressure. When decreasing and eliminating the friction force applied to the rear wheel 4, the relief valve 38b is controlled as an actuator to be in an open state, causing brake fluid to flow out of the wheel cylinder 27b and reducing the hydraulic pressure.

[0100] With this configuration, the friction-type rear wheel braking mechanism 21b brakes the rear wheel 4 with a frictional force corresponding to the control of the rear wheel pump 35b and relief valve 38b. Therefore, by using the pump 35b and relief valve 38b as actuators that operate in response to the input of an electrical control signal, the friction-type rear wheel braking mechanism 21b can be implemented in a by-wire manner, making it easier to mount the brake system 100 onto the motorcycle 10.

[0101] In the brake system 100 of this embodiment, the fluid passages 25c to 25e, the loading valve 32, the release valve 33, the accumulator 34, the pump 35a, the motor 36, the switching valve 38a, and the pressure boosting valve 39 of the friction-type front wheel braking mechanism 21a are provided on the base 31, and the fluid passages 26c and 26d, the pump 35b, and the relief valve 38b of the friction-type rear wheel braking mechanism 21b are provided on the base 31. In other words, at least a part of the friction-type front wheel braking mechanism 21a and at least a part of the friction-type rear wheel braking mechanism 21b are provided on a common base 31.

[0102] With this configuration, at least a portion of the friction-type front wheel braking mechanism 21a and at least a portion of the friction-type rear wheel braking mechanism 21b are provided on a common base 31, making it easy to attach the friction-type front wheel braking mechanism 21a and the friction-type rear wheel braking mechanism 21b to the motorcycle 10.

[0103] The brake system 100 of this embodiment includes an operator 11 operated by the rider. For example, in the linked brake control performed by the control device 60, the required braking force based on the amount of operation of the operator 11 is distributed and generated between the regenerative braking force of the rear wheel braking unit 40 and the braking force of the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20. Thus, the operator 11 is common to both the front wheel braking unit 20 and the rear wheel braking unit 40.

[0104] With this configuration, the rider can operate the front wheel braking unit 20 and the rear wheel braking unit 40 by operating the control element 11, thereby improving the operability of the brake system 100.

[0105] The brake system 100 of this embodiment is configured to include one operator 11 that is hydraulically connected to the friction-type front wheel braking mechanism 21a of the front wheel braking section 20, as an operator operated by the rider.

[0106] With this configuration, the rider can operate the brake system 100 by operating a single control element 11, thereby improving the operability of the brake system 100.

[0107] In the brake system 100 of this embodiment, the operator 11 operated by the rider is configured as a brake lever provided on the handlebar 2, and is operated by the rider's hand.

[0108] With this configuration, the rider can operate the brake system 100 by operating the control element 11 with their hand. This allows for more precise control compared to, for example, operating with the foot, thus improving the operability of the brake system 100.

[0109] In this embodiment, the brake system 100 is configured to include one operator 11 that is hydraulically connected to the friction-type front wheel braking mechanism 21a. However, the brake system may also include a first operator and a second operator different from the first operator, wherein the friction-type front wheel braking mechanism 21a and the regenerative braking mechanism 5 are operated by the first operator and the friction-type rear wheel braking mechanism 21b is operated by the second operator; or the friction-type front wheel braking mechanism 21a is operated by the first operator and the friction-type rear wheel braking mechanism 21b and the regenerative braking mechanism 5 are operated by the second operator; or the friction-type front wheel braking mechanism 21a and the friction-type rear wheel braking mechanism 21b are operated by the first operator and the regenerative braking mechanism 5 is operated by the second operator. With these configurations, the first and second operators control the corresponding friction-type front wheel braking mechanism 21a, friction-type rear wheel braking mechanism 21b, and regenerative braking mechanism 5. Therefore, the rider can select either the first or second operator to use the friction-type front wheel braking mechanism 21a, friction-type rear wheel braking mechanism 21b, and regenerative braking mechanism 5, thereby improving the operability of the brake system 100.

[0110] The brake system 100 of this embodiment includes a control device 60 that controls the braking force of the rear wheel braking unit 40. The control device 60 is configured to, for example, in linked brake control, distribute the braking force requested by the rider based on the movement of the operator 11 (requested braking force) to the braking force of the friction-type front wheel braking mechanism 21a and the braking force of the regenerative braking mechanism 5, and to generate and increase the respective braking forces.

[0111] With this configuration, the control device 60 distributes the required braking force based on the movement of the operator 11 to the braking force of the friction-type front wheel braking mechanism 21a and the braking force of the regenerative braking mechanism 5, thereby generating braking force on the front wheel 3 and rear wheel 4, and improving the stability of the motorcycle 10 during braking.

[0112] Furthermore, the control device 60 may be configured to distribute the required braking force to the braking force provided by the friction-type rear wheel braking mechanism 21b and the braking force provided by the regenerative braking mechanism 5, and to control the generation and increase of each braking force. With such a configuration, the required braking force can be generated on the rear wheels 4.

[0113] The brake system 100 of this embodiment includes a control device 60 that controls the braking force provided by the front wheel braking unit 20 and the rear wheel braking unit 40. The control device 60 is configured to, for example, when a lock control operation is being performed and the front wheel 3 is locked or there is a possibility of locking, reduce the braking force provided by the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20, while increasing the braking force provided by the friction-type rear wheel braking mechanism 21b of the rear wheel braking unit 40.

[0114] With this configuration, when the front wheel 3 locks up or there is a possibility of locking up, the braking force of the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20 can be reduced, thereby releasing or avoiding locking at the front wheel 3. At the same time, the braking force of the friction-type rear wheel braking mechanism 21b of the rear wheel braking unit 40 can be increased, thereby compensating for the reduced braking force at the front wheel 3 at the rear wheel 4.

[0115] The brake system 100 of this embodiment includes a control device 60 that controls the braking force provided by the front wheel braking unit 20 and the rear wheel braking unit 40. The control device 60 is configured to, for example, when slip occurs or is likely to occur in the front wheel 3 during cornering while performing a slip control operation, reduce the braking force provided by the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20, while increasing the braking force provided by the friction-type rear wheel braking mechanism 21b of the rear wheel braking unit 40.

[0116] With this configuration, when slippage occurs or is likely to occur in the front wheel 3, the braking force of the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20 can be reduced, thereby releasing or avoiding the slippage in the front wheel 3. At the same time, the braking force of the friction-type rear wheel braking mechanism 21b of the rear wheel braking unit 40 can be increased, thereby compensating for the reduced braking force on the front wheel 3 side with the rear wheel 4 side.

[0117] The brake system 100 of this embodiment includes a control device 60 that controls the braking force of the friction-type rear wheel braking mechanism 21b. The control device 60 is configured to include an acquisition unit 63 that acquires regenerative information relating to the regenerative braking mechanism 5, and an execution unit 64 that, when it is determined based on the regenerative information that the regenerative braking mechanism 5 is unable to generate regenerative braking force, acts as an actuator to activate the pump 35b and relief valve 38b of the friction-type rear wheel braking mechanism 21b, thereby executing control to generate and increase braking force on the rear wheels 4 using the friction-type rear wheel braking mechanism 21b.

[0118] With this configuration, the execution unit 64 of the control device 60 determines that the regenerative braking mechanism 5 cannot generate regenerative braking force (for example, if the available capacity of the power storage device of the power supply unit 6 is insufficient and the motor 5 cannot generate power, or if there is a malfunction in the motor 5 and it cannot generate power, etc.), and activates the pump 35b and the relief valve 38b to generate and increase braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b. As a result, the braking force that is not generated by the regenerative braking mechanism 5 can be compensated for by generating braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b, thereby improving the safety of the motorcycle 10.

[0119] The brake system 100 of this embodiment includes a control device 60 that controls the braking force of the friction-type rear wheel braking mechanism 21b. The control device 60 is configured to include an acquisition unit 63 that acquires abnormal information regarding an abnormality in the front wheel braking unit 20, and an execution unit 64 that, when it is determined that an abnormality has occurred in the front wheel braking unit 20 based on the abnormal information, acts as an actuator to activate the pump 35b and relief valve 38b of the friction-type rear wheel braking mechanism 21b, thereby executing control to generate and increase braking force on the rear wheels 4 using the friction-type rear wheel braking mechanism 21b.

[0120] With this configuration, when the execution unit 64 of the control device 60 determines that there is an abnormality in the front wheel braking unit 20, it activates the pump 35b and the relief valve 38b to generate and increase braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b. As a result, the braking force that is not generated in the front wheel braking unit 20 due to the abnormality can be compensated for by generating braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b, thereby improving the safety of the motorcycle 10.

[0121] <Embodiment 2> Embodiment 2 of the brake system and saddle-type vehicle equipped with the brake system according to the present invention will be described with reference to the drawings. Note that the configuration of the saddle-type vehicle and brake system in this embodiment includes the same configuration as that of Embodiment 1 described above; therefore, the differences will be described here primarily. Configurations identical to those in Embodiment 1 may be omitted from the description.

[0122] In Embodiment 1, the brake system 100 includes a hydraulic unit consisting of a friction-type rear wheel braking mechanism 21b, a by-wire type that generates friction braking force on the rear wheel 4 in the rear wheel braking section 40, and a friction-type rear wheel braking mechanism 21b, which consists of a friction-applying device 22b, a reservoir 24b, fluid passages 26a to 26e, a wheel cylinder 27b, a hydraulic pressure adjustment unit 30, etc., and in this configuration, the friction material of the friction-applying device 22b is moved in accordance with the hydraulic pressure of the brake fluid supplied to the wheel cylinder 27a of the friction-applying device 22b, thereby applying friction braking force to the rear wheel 4. However, in Embodiment 2, the brake system 100 includes a friction-applying unit 70 that applies friction force to the rear wheel 4 in accordance with the movement of friction materials 71a and 71b by a moving device 73 acting as an actuator based on a control signal from the control device 60.

[0123] A saddle-type vehicle equipped with the brake system of Embodiment 2 will be described with reference to Figures 5 to 7.

[0124] Figure 5 is a diagram illustrating the brake system according to Embodiment 2. Figure 6 is a diagram illustrating the friction-applying unit of the brake system according to Embodiment 2. Figure 7 is a diagram illustrating the system configuration of the brake system according to Embodiment 2.

[0125] <About the braking system> As shown in Figure 5, the brake system 100 comprises a single control element 11 operated by the rider of the motorcycle 10, a front wheel braking unit 20 for braking the front wheel 3, a rear wheel braking unit 40 for braking the rear wheel 4, and a control device 60 for controlling the braking force of the front wheel 3 and the rear wheel 4, and is mounted on the motorcycle 10 as a saddle-type vehicle. The friction-type rear wheel braking mechanism 21b of the rear wheel braking unit 40 includes a friction-applying unit 70 controlled by the control device 60.

[0126] As shown in Figure 6, the friction-applying unit 70 is configured as a floating caliper and includes friction materials 71a and 71b, a spindle 72 for adjusting the distance of the friction materials 71a and 71b from the rear wheel disc rotor 4a, and a moving device 73 for generating linear motion in the spindle 72.

[0127] The friction materials 71a and 71b consist of a pair of friction materials 71a and 71b that sandwich the rear wheel disc rotor 4a, and frictional force is generated when the opposing surfaces of the friction materials 71a and 71b that face the disc rotor 4a are pressed against the disc rotor 4a.

[0128] The spindle 72 is connected to the moving device 73 and is capable of linear motion, adjusting the distance of the friction materials 71a and 71b from the disc rotor 4a through this linear motion. The linear motion of the spindle 72 may be transmitted to the friction materials 71a and 71b via an elastic member, or via a fluid such as a working fluid. Hereinafter, among the directions of linear motion of the spindle 72, the direction that decreases the distance of the friction materials 71a and 71b from the disc rotor 4a, that is, the direction that brings the friction materials 71a and 71b closer to and presses against the disc rotor 4a, may be referred to as the first direction, and the direction opposite to the first direction, that is, the direction that moves the friction materials 71a and 71b away from the disc rotor 4a, may be referred to as the second direction.

[0129] The moving device 73 is, for example, a motor, which operates in response to a control signal from the control device 60 to generate linear motion in the spindle 72, thereby adjusting the distance between the friction materials 71a, 71b and the spindle 72. The moving device 73 is mounted on the outside of the friction-applying unit 70 and is unitized together with the friction-applying unit 70. The friction-applying unit 70 may have other structures. For example, the friction-applying unit 70 may be configured as an opposing caliper. Alternatively, the moving device 73 may be built into the friction-applying unit 70.

[0130] In the friction-applying unit 70, the spindle 72 is moved in a first direction by the moving device 73, reducing the distance of the friction materials 71a and 71b from the disc rotor 4a, and the friction braking force increases as the friction materials 71a and 71b are pressed against the disc rotor 4a. On the other hand, the spindle 72 is moved in a second direction by the moving device 73, increasing the distance of the friction materials 71a and 71b from the disc rotor 4a, and the friction braking force decreases as the friction materials 71a and 71b are moved away from the disc rotor 4a.

[0131] As shown in Figure 7, the control device 60 includes a first control unit 61 that controls the operation of the moving device 73 of the friction-applying unit 70 of the front wheel braking unit 20, and a second control unit 62 that controls the operation of the electric motor 5 of the rear wheel braking unit 40 as a generator.

[0132] The control device 60 receives output signals from, for example, the front wheel rotation speed sensor 81, the friction material motion sensor 85, the rear wheel rotation speed sensor 91, the remaining battery charge sensor 92, and the surrounding environment sensor 93, either via wired or wireless connection. Output signals from other sensors may also be input to the control device 60. Based on these sensor output signals, the control device 60 derives target braking forces to be generated on the front wheels 3 and rear wheels 4, respectively, as in Embodiment 1 described above. The first control unit 61 outputs a command signal corresponding to the target braking force to be generated on the front wheels 3 to the driver of the mobile device 73 via wired or wireless connection. The second control unit 62 also outputs a command signal corresponding to the target braking force to be generated on the rear wheels 4 to the control device that controls the power to charge the battery charger, either via wired or wireless connection.

[0133] The friction material motion sensor 85 detects the motion of the friction materials 71a and 71b of the friction-applying unit 70. The friction material motion sensor 85 is held, for example, by the friction-applying unit 70. The friction material motion sensor 85 can be any type of sensor that detects a physical quantity that reflects the braking force generated on the front wheel 3 by the friction-applying unit 70. For example, the friction material motion sensor 85 may detect the amount of drive of the moving device 73, or it may detect the reaction force acting on the spindle 72. The friction material motion sensor 85 may also detect other physical quantities that are substantially convertible to the amount of drive of the moving device 73 or the reaction force acting on the spindle 72.

[0134] The first control unit 61 and the second control unit 62 are housed, for example, within the housing of the friction-applying unit 70. The first control unit 61 and the second control unit 62 are unitized together with the friction materials 71a and 71b, the spindle 72, and the moving device 73. The second control unit 62 may also be unitized together with the electric motor 5.

[0135] The control device 60, for example, in the linked brake control, lock control operation, slip control operation, stop support control operation, emergency brake control operation, etc., distributes part or all of the target braking force of the front wheel braking unit 20 and the rear wheel braking unit 40 to the friction braking force of the friction-type rear wheel braking mechanism 21b. At this time, the control device 60 drives the moving device 73 to move the friction materials 71a and 71b so that the distance of the friction materials 71a and 71b from the disc rotor 4a is a distance corresponding to the friction braking force to be distributed to the friction-type rear wheel braking mechanism 21b.

[0136] The control device 60 includes an acquisition unit 63 that acquires abnormal information regarding the abnormality of the front wheel braking unit 20, and an execution unit 64 that performs control of the moving device 73 as an actuator based on the abnormal information.

[0137] The acquisition unit 63 monitors, for example, the output of the rear wheel rotation speed sensor 91 and the remaining charge sensor 92, and if it determines that the regenerative braking mechanism cannot generate regenerative braking force (for example, if the rotation speed of the rear wheels 4 is lower than the reference value for generating power, or if there is insufficient available capacity in the energy storage device), it sets regenerative information indicating that regenerative braking force cannot be generated in the storage means of the control device 60.

[0138] Furthermore, the acquisition unit 63 monitors, for example, the output history of the front wheel rotation speed sensor 81, the first brake fluid pressure sensor 82, and the second brake fluid pressure sensor 83, as well as the operation of the first control unit 61 and the second control unit 62, and if it determines that the front wheel braking unit 20 is not functioning normally, it sets abnormality information indicating that there is an abnormality in the front wheel braking unit 20 into the storage means of the control device 60.

[0139] In response to this, if the execution unit 64 determines, based on the regenerative information set in the control device 60 storage means, that it is not possible to generate regenerative braking force, it activates the moving device 73 as an actuator to perform control to generate, increase, decrease, and eliminate friction braking force by the friction-type rear wheel braking mechanism 21b based on, for example, the driving state of the motorcycle 10, the operating state of the operator 11, etc.

[0140] Furthermore, if the execution unit 64 determines that an abnormality has occurred in the front wheel braking unit 20 based on abnormality information set in the control device 60 storage means, it activates the moving device 73 as an actuator to perform control that generates, increases, decreases, and eliminates the friction braking force of the friction-type rear wheel braking mechanism 21b by the friction-applying unit 70, based on, for example, the driving state of the motorcycle 10, the operating state of the operator 11, etc.

[0141] As described above, the rear wheel braking unit 40 of this embodiment is configured such that the friction-type rear wheel braking mechanism 21b includes a friction-applying unit 70, and can generate frictional braking force on the rear wheels 4 in accordance with the control of the moving device 73, which acts as an actuator.

[0142] <Effects of the braking system> The motorcycle 10 of this embodiment is a rear-wheel drive type saddle-type vehicle in which the rear wheel 4 is driven by an electric motor 5, and the brake system 100 of the motorcycle 10 is a brake system for a rear-wheel drive motorcycle 10 and includes a front wheel braking unit 20 that brakes the front wheel 3 of the motorcycle 10, a rear wheel braking unit 40 that brakes the rear wheel 4 of the motorcycle 10, and an operating element 11 that is operated by the rider of the motorcycle 10, and the front wheel braking unit 20 is connected to the operating element 11 The rear wheel braking section 40 includes a friction-type front wheel braking mechanism 21a that is connected by hydraulic pressure and brakes the front wheel 3 with a frictional force corresponding to the hydraulic pressure, and a regenerative braking mechanism (electric motor 5) that generates a regenerative braking force on the rear wheel 4 in accordance with the rotation of the rear wheel 4, and a by-wire type friction-type rear wheel braking mechanism 21b that is not connected by hydraulic pressure to the operator 11 and brakes the rear wheel 4 with a frictional force corresponding to the control of a moving device 73 which acts as an actuator and operates in response to the input of an electrical control signal.

[0143] With this configuration, the rear wheel braking unit 40 is equipped with a regenerative braking mechanism and a drive-by-wire friction-type rear wheel braking mechanism 21b that is not hydraulically connected to the operator 11 and brakes the rear wheel 4 with frictional force corresponding to the control of the moving device 73 as an actuator. As a result, the friction-type rear wheel braking mechanism 21b can generate frictional force on the rear wheel 4 and brake it, increasing the braking force that can be generated by the brake system 100 and improving the safety of the motorcycle 10 when braking. Furthermore, since the rear wheel braking unit 40 is equipped with a friction-type rear wheel braking mechanism 21b that is different from the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20, even if, for example, a malfunction occurs in the friction-type front wheel braking mechanism 21a of the front wheel braking unit 20 and the front wheel braking unit 20 is unable to brake the front wheel 3, the rear wheel braking unit 40 can brake the rear wheel 4, improving the safety of the motorcycle 10 when braking.

[0144] In the brake system 100 of this embodiment, the drive-by-wire friction rear wheel braking mechanism 21b provided in the rear wheel braking unit 40 includes a friction application unit 70 that applies a friction force to the rear wheel 4 in accordance with the movement of the friction materials 71a, 71b, and a moving device 73 that moves the friction materials 71a, 71b as an actuator controlled by the control device 60. When generating and increasing the friction force applied to the rear wheel 4, the moving device 73 is controlled to move the friction materials 71a, 71b in a direction that presses them against the disc rotor 4a of the rear wheel 4. When decreasing and eliminating the friction force applied to the rear wheel 4, the moving device 73 is controlled to move the friction materials 71a, 71b in a direction that moves them away from the disc rotor 4a of the rear wheel 4.

[0145] With this configuration, in the brake system 100, the friction-type rear wheel braking mechanism 21b moves the friction materials 71a and 71b by controlling the moving device 73 with the control device 60, and applies a friction force to the rear wheel 4 corresponding to that movement. Therefore, the braking force of the rear wheel 4 can be increased and decreased regardless of the movement of the operator 11. Furthermore, since the friction-type rear wheel braking mechanism 21b is configured to increase and decrease the friction braking force by controlling the moving device 73 with the control device 60, and is configured to generate friction braking force only on the rear wheel 4, it is sufficient to arrange the control wires connecting the control device 60 and the moving device 73 in a narrower area, thus improving the mountability of the friction-type rear wheel braking mechanism 21b.

[0146] The brake system 100 of this embodiment includes a control device 60 that controls the braking force of the friction-type rear wheel braking mechanism 21b. The control device 60 is configured to include an acquisition unit 63 that acquires abnormality information regarding an abnormality in the front wheel braking unit 20, and an execution unit 64 that, when it is determined that an abnormality has occurred in the front wheel braking unit 20 based on the abnormality information, acts as an actuator to activate the moving device 73 of the friction-type rear wheel braking mechanism 21b and executes control to generate and increase braking force on the rear wheels 4 using the friction-type rear wheel braking mechanism 21b.

[0147] With this configuration, the execution unit 64 of the control device 60, when it determines that there is an abnormality in the front wheel braking unit 20, activates the moving device 73 to generate and increase braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b. As a result, the braking force that is not generated in the front wheel braking unit 20 due to the abnormality can be compensated for by generating braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b, thereby improving the safety of the motorcycle 10.

[0148] The brake system 100 of this embodiment includes a control device 60 that controls the braking force of the friction-type rear wheel braking mechanism 21b. The control device 60 is configured to include an acquisition unit 63 that acquires regenerative information relating to the regenerative braking mechanism 5, and an execution unit 64 that, when it is determined based on the regenerative information that the regenerative braking mechanism 5 is unable to generate regenerative braking force, acts as an actuator to activate the moving device 73 of the friction-type rear wheel braking mechanism 21b, thereby executing control to generate and increase braking force on the rear wheels 4 using the friction-type rear wheel braking mechanism 21b.

[0149] With this configuration, the execution unit 64 of the control device 60 determines that the regenerative braking mechanism 5 cannot generate regenerative braking force (for example, if the available capacity of the power storage device of the power supply unit 6 is insufficient and the motor 5 cannot generate power, or if there is a malfunction in the motor 5 and it cannot generate power, etc.), and activates the moving device 73 to generate and increase braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b. As a result, the braking force that is not generated by the regenerative braking mechanism 5 can be compensated for by generating braking force on the rear wheel 4 using the friction-type rear wheel braking mechanism 21b, thereby improving the safety of the motorcycle 10.

[0150] Although a brake system according to an embodiment has been described above, the brake system according to the present invention is not limited to the embodiments described. For example, only a part of the embodiment may be implemented. [Explanation of Symbols]

[0151] 1 Body, 2 Handle, 3 Front wheel, 4 Rear wheel, 5 Electric motor, 6 Power unit, 10 Motorcycle, 11 Controls, 20 Front wheel braking unit, 21a Friction-type front wheel braking mechanism, 21b Friction-type rear wheel braking mechanism, 22a Friction-applying device, 22b Friction-applying device, 23 Master cylinder, 24a Reservoir, 24b Reservoir, 25a~25e Fluid passage, 26a~26e Fluid passage, 27a Wheel cylinder, 27b Wheel cylinder, 30 Hydraulic pressure adjustment unit, 31 Base, 32 Load valve, 33 Release valve, 34 Accumulator, 35a Pump, 35b Pump (actuator), 36 Motor, 37 Housing, 38a Switching valve, 38b Relief valve (actuator), 39 Pressure boosting valve, 40 Rear wheel braking unit, 60 Control device, 61 First control unit, 62 Second control unit, 70 Friction application unit, 71a Friction material, 71b Friction material, 72 Spindle, 73 Moving device (actuator), 81 Front wheel rotation speed sensor, 82 First brake fluid pressure sensor, 83 Second brake fluid pressure sensor, 85 Friction material motion sensor, 91 Rear wheel rotation speed sensor, 92 Battery level sensor, 93 Surround environment sensor, 100 Brake system

Claims

1. A brake system (100) for a rear-wheel-drive saddle-type vehicle (10), A front wheel braking unit (20) that brakes the front wheel (3) of the aforementioned saddle-type vehicle (10), A rear wheel braking unit (40) that brakes the rear wheels (4) of the aforementioned saddle-type vehicle (10), At least one operator (11) operated by the rider of the aforementioned saddle-type vehicle (10), Includes, The front wheel braking unit (20) includes a friction-type front wheel braking mechanism (21a) that is hydraulically connected to the operator (11) and brakes the front wheel (3) with a frictional force corresponding to the hydraulic pressure. The rear wheel braking unit (40) includes a regenerative braking mechanism (5) that generates a regenerative braking force on the rear wheel (4) in accordance with the rotation of the rear wheel (4). The rear wheel braking unit (40) further includes a drive-by-wire friction rear wheel braking mechanism (21b) that is not hydraulically connected to the operating element (11) and brakes the rear wheel (4) with a frictional force corresponding to the control of the actuators (35b, 38b, 73). The friction-type front wheel braking mechanism (21a) and the friction-type rear wheel braking mechanism (21b) are operated by the first operator (11), The regenerative braking mechanism (5) is operated by a second operator (11) which is different from the first operator. Brake system.

2. The friction-type rear wheel braking mechanism (21b) is, A friction device (22b) is provided which includes a wheel cylinder (27b) to which the hydraulic pressure of brake fluid is input, and which applies a friction force to the rear wheel (4) in accordance with the hydraulic pressure of the wheel cylinder (27b), The actuator includes a pump (35b) that moves brake fluid to the wheel cylinder (27b), The actuator includes a relief valve (38b) that releases brake fluid from the wheel cylinder (27b), Includes, When generating and increasing the frictional force applied to the rear wheel (4), the pump (35b) is driven, which increases the hydraulic pressure of the wheel cylinder (27b). When the frictional force applied to the rear wheel (4) is reduced and eliminated, the relief valve (38b) is opened, thereby reducing the hydraulic pressure of the wheel cylinder (27b). The brake system according to claim 1.

3. At least a portion of the friction-type front wheel braking mechanism (21a) and at least a portion of the friction-type rear wheel braking mechanism (21b) are provided on a common base (31). The brake system according to claim 2.

4. The friction-type rear wheel braking mechanism (21b) is, A friction-applying device (70) that applies a frictional force to the rear wheel (4) in accordance with the movement of the friction material (71a, 71b), The actuator includes a moving device (73) for moving the friction materials (71a, 71b), Includes, When generating and increasing the frictional force applied to the rear wheel (4), the moving device (73) is controlled to move the friction material (71a, 71b) in a direction that presses it against the rear wheel (4). When reducing and eliminating the frictional force applied to the rear wheel (4), the moving device (73) is controlled to move the friction material (71a, 71b) away from the rear wheel (4). The brake system according to claim 1.

5. The operator (11) includes an operator operated by the rider's hand, The brake system according to any one of claims 1 to 4.

6. The operator operated by the rider's hand is a brake lever. The brake system according to claim 5.

7. The operator (11) includes an operator operated by the rider's foot, The brake system according to any one of claims 1 to 4.

8. The aforementioned brake system (100) Includes a control device (60) that controls the braking force from the front wheel braking unit (20) and the rear wheel braking unit (40), The control device (60) is When the front wheel (3) locks up or there is a possibility of locking up, or when the saddle-type vehicle (10) slips or there is a possibility of slipping while turning, the braking force of the friction-type front wheel braking mechanism (21a) is reduced while the braking force of the friction-type rear wheel braking mechanism (21b) is increased. The brake system according to any one of claims 1 to 4.

9. The aforementioned brake system (100) The system includes a control device (60) that controls the braking force provided by the friction-type rear wheel braking mechanism (21b), The control device (60) is An acquisition unit (63) that acquires regenerative information relating to the regenerative braking mechanism (5), If it is determined that the regenerative braking mechanism (5) cannot generate regenerative braking force based on the regenerative information, the execution unit (64) performs control to activate the actuators (35b, 38b, 73) to generate and increase the braking force of the friction-type rear wheel braking mechanism (21b), Equipped with The brake system according to any one of claims 1 to 4.

10. The aforementioned brake system (100) The system includes a control device (60) that controls the braking force provided by the friction-type rear wheel braking mechanism (21b), The control device (60) is An acquisition unit (63) acquires abnormal information regarding an abnormality in the front wheel braking unit (20), If it is determined that an abnormality has occurred in the front wheel braking unit (20) based on the abnormality information, the execution unit (64) executes control to activate the actuators (35b, 38b, 73) to generate and increase braking force, Equipped with The brake system according to any one of claims 1 to 4.

11. A saddle-type vehicle (10) equipped with a brake system (100) according to any one of claims 1 to 4.

Images