Brake fluid pressure control device and saddle-type vehicle

Abstract

Provided is a brake fluid pressure control device that can reduce the torque required to drive a pump when a motor is running. A brake fluid pressure control device 10 that controls the brake fluid pressure of a brake system 100 mounted on a motorcycle 1 comprises: a base body 60 in which is formed a first liquid passage 23, which is a liquid passage for a brake fluid; a first pump 27 that pressure-feeds the brake fluid in the first liquid passage 23; a motor 50 that drives the first pump 27; and a control board 70 that controls the operating state of the motor 50. The first pump 27 comprises: an eccentric body 52 that rotates while being eccentric with respect to the rotation center of an output shaft 51 of the motor 50; and a plunger 27e that reciprocates by being pressed by the eccentric body 52, the plunger 27e including a thermoplastic resin, and at least some of the thermoplastic resin configured to transition to a rubber state when the motor 50 is running.

Description

[0001] [Document name] Statement

[0002] [Title of invention] Brake fluid pressure control device and saddle-type vehicle

[0003] [Technical Field]

[0004]

[001] The present invention relates to a brake fluid pressure control device that controls the hydraulic pressure of brake fluid in a saddle-ride type vehicle, and to a saddle-ride type vehicle equipped with the brake fluid pressure control device.

[0005] [Background technology]

[0006]

[002] Conventionally, some straddle-type vehicles (e.g., motorcycles, etc.) are equipped with brake fluid pressure control devices that control the hydraulic pressure of brake fluid in a brake system that brakes the wheels. One such brake fluid pressure control device is, for example, one that is driven by an electric motor and includes a pump that pressure-feeds brake fluid (see, for example, Patent Document 1).

[0007] [Prior art documents]

[0008] [Patent documents]

[0009]

〇 0 0 3

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2023-131756

[0011] Summary of the Invention

[0012] [Problem to be solved by the invention]

[0013]

[0004] A brake fluid pressure control device such as that described in Patent Document 1 includes a pump that is driven to rotate by an electric motor. When power is applied to the electric motor, the electric motor generates heat, causing its temperature to rise. As the temperature of the magnets included in the electric motor rises, the magnetic flux density tends to decrease, and the output torque of the electric motor decreases as the temperature of the electric motor increases. When the electric motor is in a driven state, the increase in temperature can cause the output torque of the electric motor to fall below the torque required to continue driving the pump to rotate. In such a case, the pump may stop rotating, making it difficult for the brake fluid pressure control device to control the brake fluid pressure.

[0014]

[0005] The present invention has been made against the background of the above-mentioned problems, and aims to provide a brake fluid pressure control device that can reduce the torque required to drive the pump when the motor is driven.

[0015] [Means for solving the problem]

[0016]

[0006] The brake fluid pressure control device according to the present invention is a brake fluid pressure control device that controls the hydraulic pressure of brake fluid in a brake system mounted on a saddle-ride type vehicle, and comprises: a base body in which a fluid path for brake fluid is formed; a pump that pressurizes the brake fluid in the fluid path; an electric motor that drives the pump; and a control board that controls the operating state of the electric motor; the electric motor comprises: an output shaft; and an eccentric body that is provided on the output shaft and rotates eccentrically about the center of rotation of the output shaft; the pump comprises: a plunger that is pressed by the eccentric body and moves reciprocally; and a spring that presses the plunger against the eccentric body; the plunger includes a thermoplastic resin, and at least a part of the thermoplastic resin is transformed into a rubber state when the electric motor is in a driving state.

[0017] [0 0 0 7] According to this configuration, the plunger of the pump contains thermoplastic resin, and when the electric motor is in a driving state, at least a part of the thermoplastic resin is transformed into a rubbery state. Therefore, the plunger that has transformed into a rubbery state is compressed by being pressed by the eccentric and the spring and by being exposed to the hydraulic pressure of the brake fluid, and its dimensions are reduced. By utilizing this fact, the stroke length of the reciprocating motion of the plunger can be shortened, and the torque required to drive the pump can be reduced.

[0018]

[0008] A straddle-type vehicle according to the present invention is configured to include the above-described brake fluid pressure control device. With this configuration, the straddle-type vehicle can achieve the same effects as the above-described brake fluid pressure control device.

[0019] 〇

[0020]

[0009] The present invention may have only the specific features of the invention set forth in the claims, or may have both the specific features of the invention and features other than the specific features of the invention.

[0021] [Brief explanation of the drawings]

[0022] [ 0 0 1 0 ]

[0023] [Figure 1] A diagram for explaining a motorcycle on which a brake fluid pressure control device of the first embodiment is installed.

[0024] [Figure 2] A diagram for explaining the brake system of a motorcycle controlled by a brake fluid pressure control device.

[0025] [Figure 3] A diagram for explaining a brake fluid pressure control device.

[0026] [Figure 4] A diagram for explaining a brake fluid pressure control device.

[0027] [Figure 5] A diagram for explaining the pump of the brake fluid pressure control device.

[0028] FIG. 6 is a diagram for explaining a pump of a brake fluid pressure control device of a second embodiment.

[0029] [Mode for Carrying Out the Invention]

[0030]

[0011] Embodiments of a brake fluid pressure control device according to the present invention and a saddle-type vehicle equipped with the brake fluid pressure control device will be described with reference to the drawings. In the embodiments, an example will be described in which the brake fluid pressure control device is mounted on a motorcycle as a saddle-type vehicle, but the brake fluid pressure control device according to the present invention may be mounted on saddle-type vehicles other than motorcycles. A saddle-type vehicle refers to any vehicle on which a rider straddles and rides. Examples of saddle-type vehicles include motor cycles, buggies, and bicycles. Motor cycles include motor cycles and motor tricycles that use an engine or an electric motor as a propulsion source, and include, for example, motorcycles, scooters, and electric scooters. A bicycle refers to any vehicle that can be propelled by the rider's pedaling force applied to the pedals. Examples of bicycles include standard bicycles, electrically assisted bicycles, and electric bicycles.

[0031]

[0012] In addition, in the embodiment, an example of a configuration in which the brake fluid pressure control device has two fluid pressure circuits and two pumps will be described, but the brake fluid pressure control device may have a configuration in which only one fluid pressure circuit is provided, or a configuration in which three or four or more fluid pressure circuits are provided, or a configuration in which only one pump is provided, or a configuration in which three or four or more pumps are provided. In addition, in the present embodiment, a case in which the brake fluid pressure control device is applied to a brake system that brakes the front and rear wheels of a motorcycle will be described, but the brake fluid pressure control device may also be applied to a brake system that brakes only one of the front and rear wheels.

[0032]

[0013] Furthermore, the configurations, operations, etc. of the brake fluid pressure control device described in the embodiments are merely examples, and the brake fluid pressure control device according to the present invention is not limited to such configurations, operations, etc. Furthermore, in each drawing, the same or similar members or parts may be denoted by the same reference numerals or may not be denoted by the reference numerals. Furthermore, detailed structures may be simplified or omitted from the illustration as appropriate.

[0033] [ 0 0 1 4 ]

[0034] <First Embodiment> A brake fluid pressure control device according to this embodiment will be described with reference to Figs. 1 to 5. Fig. 1 is a diagram for explaining a motorcycle on which the brake fluid pressure control device of this embodiment is mounted. Fig. 2 is a diagram for explaining a brake system controlled by the brake fluid pressure control device. Figs. 3 and 4 are diagrams for explaining the brake fluid pressure control device. Fig. 5 is a diagram for explaining a pump provided in the brake fluid pressure control device.

[0015]

[0035] <Regarding the saddle-type vehicle and brake system> The motorcycle 1 as a saddle-type vehicle equipped with the brake fluid pressure control device 100, and the brake system 100 of the motorcycle 1 controlled by the brake fluid pressure control device 100 will be described with reference to Figures 1 and 2.

[0036]

[0016] As shown in FIG. 1, a motorcycle 1 includes a body 2, a handlebar 3 rotatably mounted on the body 2, a front wheel 4 rotatably mounted on the body 2 together with the handlebar 3, a rear wheel 5 rotatably mounted on the body 2 and driven by a drive source (not shown, for example, an engine or an electric motor), a front wheel disc rotor 4a that rotates with the front wheel 4, a rear wheel disc rotor 5a that rotates with the rear wheel 5, a brake system 100 that brakes the front wheel 4 and the rear wheel 5, and a brake fluid pressure control device io that controls the brake system 100.

[0037]

[0017] As shown in FIG. 2, the brake system 100 includes a first operator 6 and a second operator 7 operated by a rider, a front wheel braking mechanism 20 that brakes the front wheel 4, a rear wheel braking mechanism 30 that brakes the rear wheel 5, a front wheel friction member 25 that generates a friction force on the front wheel disc rotor 4a, a rear wheel friction member 35 that generates a friction force on the rear wheel disc rotor 5a, and a brake fluid pressure control device io.

[0038] In this embodiment, the first operator 6 may be, for example, a brake lever provided on the handlebar 3 and operated by the rider's hand. The second operator 7 may be, for example, a brake pedal provided below the body 2 and operated by the rider's foot.

[0039]

[0019] As shown in FIG. 2, the front wheel braking mechanism 20 is made up of a first master cylinder 21 to which the movement of the first operating element 6 is transmitted, a first brake fluid reservoir 22 attached to the first master cylinder 21, a first wheel cylinder 24 connected to the first master cylinder 21 via a first fluid path 23 filled with brake fluid, a front wheel friction member 25 pressed against the front wheel disc rotor 4a by the hydraulic pressure of the brake fluid in the first wheel cylinder 24, and a brake fluid pressure control device 10 described below. The rear wheel braking mechanism 30 is composed of a second master cylinder 31 to which the motion of the second operating element 7 is transmitted, a second reservoir 32 of brake fluid attached to the second master cylinder 31, a second wheel cylinder 34 connected to the second master cylinder 31 via a second fluid path 33 filled with brake fluid, a rear wheel friction member 35 pressed against a rear wheel disc rotor 5a by the hydraulic pressure of the brake fluid in the second wheel cylinder 34, and a brake fluid pressure control device 10. As will be described later, the first fluid path 23 and portions 23b, 23c, 33b, and 33c of the second fluid path 33 are formed as internal fluid paths in a base 60 of the brake fluid pressure control device 10. The brake fluid pressure control device 10 is disposed, for example, in the body 2 of the motorcycle 1 (see FIG. 1).

[0040]

[0020] The front wheel braking mechanism 20 is configured to press a front wheel friction member 25 against a front wheel disc rotor 4a in accordance with the amount of operation of a first operating element 6 to generate a frictional force, thereby generating a braking force on the front wheels 4 in accordance with the amount of operation of the first operating element 6. The rear wheel braking mechanism 30 is configured to press a rear wheel friction member 35 against a rear wheel disc rotor 5a in accordance with the amount of operation of a second operating element 7 to generate a frictional force, thereby generating a braking force on the rear wheels 5 in accordance with the amount of operation of the second operating element 7.

[0041]

[0021] In this embodiment, the brake system 100 is configured to include a brake lever as the first operator 6 and a brake pedal as the second operator 7, but the brake system is not limited to this example. For example, the brake system may be configured to include a brake pedal as the first operator and a brake lever as the second operator, or may be configured to include one or more brake levers as the first operator and the second operator, or may be configured to include one or more brake pedals as the first operator and the second operator.

[0042]

[0022] In this embodiment, the front wheel braking mechanism 20 and the rear wheel braking mechanism 30 are configured to generate frictional force by pressing a friction member against the disc rotor, but the front wheel braking mechanism and the rear wheel braking mechanism may be configured to generate frictional force by, for example, pressing a friction member of a brake shoe against a brake drum that rotates together with the wheel, or may be configured to generate frictional force by pressing a friction member against the disc rotor or brake drum using an actuator that is electrically connected to an operator and operated in response to operation of the operator. Also, the brake system may be configured to have only one of the front wheel braking mechanism or the rear wheel braking mechanism.

[0043] [ 0 0 2 3 ]

[0044] <Regarding the Brake Fluid Pressure Control Device> The brake fluid pressure control device 100 will be described with reference to Figures 2 to 5. The brake fluid pressure control device 100 is equipped with first to fourth solenoid valves 40a to 40d, a first pump 27, a second pump 37, and a motor 50 as a fluid pressure control mechanism that controls the fluid pressure of the brake fluid in the brake system 100. The first to fourth solenoid valves 40a to 40d and the motor 50 as the fluid pressure control mechanism are controlled between energized and de-energized states by a control board 70, and by controlling their operation, the fluid pressure of the brake fluid in the brake system 100 is controlled. The brake hydraulic pressure control device 10 controls the operation of the hydraulic control mechanism using the control board 70, thereby controlling the anti-lock operation of the front wheel 4 and rear wheel 5 of the motorcycle 1, as described below.

[0045]

[0024] As shown in FIG. 2, the brake fluid pressure control device 10 includes a first main fluid line 23b connecting a first master cylinder 21 and a first wheel cylinder 24, a first solenoid valve 40a arranged in the first main fluid line 23b, a first sub-fluid line 23c branched from a region of the first main fluid line 23b closer to the first wheel cylinder 24 than the first solenoid valve 40a and connected to a region of the first main fluid line 23b closer to the first master cylinder 21 than the first solenoid valve 40a, a second solenoid valve 40b arranged in the first sub-fluid line 23c, and a second solenoid valve 40b arranged in the first sub-fluid line 23c. The first sub-fluid passage 23c includes a first accumulator 26 that is disposed in an area closer to the first master cylinder 21 than the first accumulator 26 and temporarily stores brake fluid, and a first pump 27 that is disposed in an area of ​​the first sub-fluid passage 23c that is closer to the first master cylinder 21 than the first accumulator 26. The first main fluid passage 23b and the first sub-fluid passage 23c form part of the above-mentioned first fluid passage 23.

[0046]

[0025] The brake fluid pressure control device 10 also includes a second main fluid path 33b connecting the second master cylinder 31 and the second wheel cylinder 34, and a third solenoid valve 4 arranged in the second main fluid path 33b. a second sub-fluid path 33c branching from a region of the second main fluid path 33b closer to the second wheel cylinder 34 than the third solenoid valve 40c and connected to a region of the second main fluid path 33b closer to the second master cylinder 31 than the third solenoid valve 40c; a fourth solenoid valve 40d arranged in the second sub-fluid path 33c; a second accumulator 36 arranged in a region of the second sub-fluid path 33c closer to the second master cylinder 31 than the fourth solenoid valve 40d and for temporarily storing brake fluid; and a second pump 37 arranged in a region of the second sub-fluid path 33c closer to the second master cylinder 31 than the second accumulator 36. The second main liquid path 33b and the second sub-liquid path 33c constitute part of the second liquid path 33 described above.

[0047]

[0026] The first to fourth solenoid valves 40a to 40d are controlled by a control board 70 such that the first to fourth coils 42a to 42d (see Figure 4) corresponding to each solenoid valve are energized or de-energized, and the operation of the first to fourth valve bodies 41a to 41d corresponding to each coil is controlled so that each liquid path is opened or closed.

[0048]

[0027] The first pump 27 pumps up the brake fluid stored in the first accumulator 26 and outputs it toward the first main fluid path 23b. The second pump 37 pumps up the brake fluid stored in the second accumulator 36 and outputs it toward the second main fluid path 33b. The first pump 27 and the second pump 37 are driven by a common electric motor 50. The motor 50 has its operation (stopped state and rotating state) controlled by a control board 70, which controls its energized and de-energized states. Hereinafter, the first to fourth solenoid valves 40a to 40d, the first pump 27, the second pump 37, and the motor 50 may be referred to as a hydraulic pressure control mechanism that controls the hydraulic pressure of the brake fluid.

[0049]

[0028] The control board 70 of the brake hydraulic pressure control device 10 is equipped with a controller 71, which executes predetermined programs to control the hydraulic control mechanisms 40a-40d, 27, 37, 50, etc. The controller 71 may be a single unit or may be divided into multiple units. Some or all of the controller 71 may be composed of, for example, a microcomputer, microprocessor unit, etc., or may be configured to be updatable by software such as firmware, or may be a program module executed by commands from a CPU, etc. Furthermore, the controller 71 may be provided on one control board 70, or may be provided on multiple control boards.

[0050]

[0029] The controller 71 also includes an acquisition unit 71a that acquires the detection results of various sensors (e.g., a hydraulic pressure sensor that detects the hydraulic pressure of the brake fluid, a wheel speed sensor that detects the rotational speed of the wheels, an acceleration sensor that detects the acceleration in the roll, pitch, and yaw directions of the motorcycle 1, etc.), and an execution unit 71b that controls the operation of the brake system 100 (e.g., normal operation, pressure reduction operation, etc., described below) based on the various information acquired by the acquisition unit 71a (see Figure 4).

[0051]

[0030] For example, during normal operation, the control board 70 controls the first solenoid valve 40a and the third solenoid valve 40c to an open state, and controls the second solenoid valve 40a and the fourth solenoid valve 40d to a closed state. When the rider operates the first operating element 6 in this state, the piston (not shown) of the first master cylinder 21 is pressed in accordance with the amount of operation of the first operating element 6, causing the brake fluid pressure in the first master cylinder 21 to increase. The increased fluid pressure is then supplied to the first wheel cylinder 24 via the first main fluid path 23b, causing the brake fluid pressure in the first wheel cylinder 24 to increase. The front wheel friction member 25 is then pressed against the front wheel disc rotor 4a in accordance with the hydraulic pressure in the first wheel cylinder 24, generating a frictional force that brakes the front wheel 4. When the rider operates the second operating element 7, the piston (not shown) of the second master cylinder 31 is pressed in accordance with the amount of operation of the second operating element 7, increasing the hydraulic pressure of the brake fluid in the second master cylinder 31. The increased hydraulic pressure is supplied to the second wheel cylinder 34 via the second main hydraulic path 33b, increasing the hydraulic pressure of the brake fluid in the second wheel cylinder 34. The rear wheel friction member 35 is then pressed against the rear wheel disc rotor 5a in accordance with the hydraulic pressure in the second wheel cylinder 34, generating a frictional force that brakes the rear wheel 5.

[0052]

[0031] Furthermore, for example, as control of the antilock brake operation of the front wheels, when it is determined based on the detection results of various sensors that the rotation of the front wheels 4 is locked or there is a possibility that the rotation of the front wheels 4 may lock, the control board 70 executes a pressure reducing operation to reduce the hydraulic pressure of the brake fluid in the first wheel cylinder 24. During the pressure reducing operation of the first wheel cylinder 24, the controller 71 controls the first solenoid valve 40a to a closed state and the second solenoid valve 40b to an open state, while controlling the motor 50 to drive. As a result, the brake fluid is released from the first wheel cylinder 24 to the first accumulator 26, the hydraulic pressure of the brake fluid in the first wheel cylinder 24 is reduced, and the braking force of the front wheels 4 is reduced, thereby unlocking the rotation of the front wheels 4 or preventing the front wheels 4 from locking. In addition, the brake fluid released to the first accumulator 26 is pumped up by the first pump 27 driven by the motor 50 and returned to an area of ​​the first main fluid path 23b that is closer to the first master cylinder 21 than the first solenoid valve 40a.

[0053]

[0032] Furthermore, for example, as control of the anti-lock brake operation of the rear wheels, when it is determined based on the detection results of various sensors that the rear wheels 5 are locked or may lock, the control board 70 executes a pressure reducing operation to reduce the hydraulic pressure of the brake fluid in the second wheel cylinder 34. During the pressure reducing operation of the second wheel cylinder 34, the controller 71 controls the third solenoid valve 40c to a closed state and the fourth solenoid valve 40d to an open state, while controlling the motor 50 to operate. As a result, the brake fluid is released from the second wheel cylinder 34 to the second accumulator 36, the hydraulic pressure of the brake fluid in the second wheel cylinder 34 is reduced, and the braking force of the rear wheels 5 is reduced, thereby unlocking the rotation of the rear wheels 5 or preventing them from locking. In addition, the brake fluid released to the second accumulator 36 is pumped up by the second pump 37 driven by the motor 50 and returned to the area of ​​the second main fluid path 33b closer to the second master cylinder 31 than the fourth solenoid valve 40d.

[0054]

[0033] The brake fluid pressure control device 10 may be configured to include a fluid pressure sensor that detects the fluid pressure of the brake fluid input from the first master cylinder 21 and the second master cylinder 31, and / or a fluid pressure sensor that detects the fluid pressure of the brake fluid output to the first wheel cylinder 24 and the second wheel cylinder 34. Such a fluid pressure sensor may be, for example, arranged in the main flow path or sub-flow path of the brake fluid pressure control device, or arranged in a brake fluid pipe connected to the main flow path, or arranged in the master cylinder or wheel cylinder.

[0055]

[0034] The brake fluid pressure control device 10 may also be configured to include a fluid path or the like that allows the first pump 27 to pump up brake fluid from the first reservoir 22 and output the brake fluid to the first wheel cylinder 24. In such a configuration, the control board 70 may be configured to perform a front wheel pressure-increasing operation that increases the hydraulic pressure of the brake fluid in the first wheel cylinder 24 with the brake fluid output by the first pump 27 when it is determined, for example, based on the detection results of various sensors, that the braking force of the front wheels 4 is insufficient or may become insufficient. In such a configuration, the pressure-increasing operation can increase the braking force of the front wheels 4, thereby making up for the lack of braking force.

[0056]

[0035] The brake fluid pressure control device 10 may also be configured to include a fluid path or the like that allows the second pump 37 to pump up brake fluid from the second reservoir 32 and output the brake fluid to the second wheel cylinder 34. In such a configuration, the control board 70 may be configured to perform a rear wheel pressure-increasing operation that increases the hydraulic pressure of the brake fluid in the second wheel cylinder 34 with the brake fluid output by the second pump 37 when it is determined, for example, based on the detection results of various sensors, that the braking force of the rear wheels 5 is insufficient or may become insufficient. In such a configuration, the rear wheel pressure-increasing operation increases the braking force of the rear wheels 5, thereby compensating for the insufficient braking force.

[0057]

[0036] As shown in Figures 3 and 4, the brake fluid pressure control device 10 is configured by unitizing a base body 60 in which part of the brake fluid path described above is formed as an internal fluid path, first to fourth solenoid valves 40a to 40d, a first pump 27 and a second pump 37, a first accumulator 26 and a second accumulator 36, a motor 50, a control board 70, and a housing 80 that houses the control board 70 and the like.

[0058]

[0037] The base 60 is formed, for example, from a rectangular parallelepiped block of aluminum. The first main liquid path 23b, the first sub-liquid path 23c, the second main liquid path 33a, and the second sub-liquid path 33c are formed inside the base 60.

[0059]

[0038] A motor hole 61H for accommodating the motor 50 is formed in approximately the center of the first surface 60A that constitutes the exterior of the base 60. Four valve holes 62H for accommodating the first to fourth solenoid valves 40a to 40d are formed around the motor hole 61H in the first surface 60A of the base 60. In addition, bolt holes 63H for engaging bolts 18 that secure the housing 80 to the base 60 are formed in the first surface 60A of the base 60. A second surface 60B, which continues from the first surface 60A of the base 60 and constitutes the exterior, and a third surface 60C, which faces the second surface 60B, are formed with pump holes 64H, which respectively accommodate plungers (not shown) of the first pump 27 and the second pump 37. A fourth surface 60D, which continues from the first to third surfaces 60A to 60C of the base 60 and constitutes the exterior, is formed with accumulator holes 65H, which accommodate the first accumulator 26 and the second accumulator 36. Each surface that constitutes the exterior of the base 60 may include a stepped portion or a curved portion.

[0060]

[0039] A fifth surface 60E of the base 60, which faces the fourth surface 60D and constitutes the exterior, is provided with a first master cylinder port P1 that constitutes a part of the first fluid path 23 and is connected to a brake fluid pipe 23a that connects the first master cylinder 21 and the first main fluid path 23b, a second master cylinder port P2 that constitutes a part of the second fluid path 33 and is connected to a brake fluid pipe 33a that connects the second master cylinder 31 and the second main fluid path 33b, a first wheel cylinder port P3 that constitutes a part of the first fluid path 23 and is connected to a brake fluid pipe 23d that connects the first wheel cylinder 24 and the first main fluid path 23, and a brake fluid pipe 23d that connects the second fluid path 33b. 3 and is formed with a second wheel cylinder port P4 to which a brake fluid pipe 33d, which connects the second wheel cylinder 34 and the second main fluid line 33b, is connected.

[0061]

[0040] The motor 50 is attached to the base 60 with one end of its output shaft 51 inserted into the motor hole 61H. An eccentric body 52 that rotates together with the output shaft 51 is attached to one end of the output shaft 51. The motor 50 also has an electrical terminal 53 that is electrically connected to the control board 70 at the end opposite to the side where the output shaft 51 is provided. In this embodiment, the motor 50 is attached to the base 60, but the motor may also be attached to a housing, for example.

[0062]

[0041] As will be described later, the plungers of the first pump 27 and the second pump 37 are disposed inside each pump hole 64H so as to be pressed against the outer circumferential surface of the eccentric body 52 (see FIG. 5). As the eccentric body 52 rotates, the plungers of the first pump 27 and the second pump 37 reciprocate in the axial direction of the pump hole 64H, thereby pumping brake fluid from the suction side of the first pump 27 and the second pump 37 to the discharge side.

[0063]

[0042] The first to fourth solenoid valves 40a to 40d each include a valve body and a coil. The first to fourth valve bodies 41a to 41d of the first to fourth solenoid valves 40a to 40d are inserted into the valve holes 62H, and the first to fourth coils 42a to 42d of the first to fourth solenoid valves 40a to 40d are installed on the first surface 60A of the base 60, thereby assembling the first to fourth solenoid valves 40a to 40d to the base 60.

[0064]

[0043] The first accumulator 26 and the second accumulator 36 are assembled by being housed in the accumulator holes 65H, respectively.

[0065]

[0044] As will be described later, the control board 70 includes a substrate 72 on which a controller 71, electrical wiring constituting an electronic circuit, and various electronic components (such as an integrated circuit chip 73) are arranged. The electronic circuit of the control board 70 is electrically connected to an electrical terminal 53 of the motor 50, electrical terminals 43a to 43d of the first to fourth coils 42a to 42d, output terminals of various sensors (not shown), and a connector 75 connected to an external device (not shown) provided outside the brake fluid pressure control device 10.

[0066]

[0045] The housing 80 is made of, for example, resin and is formed in a substantially rectangular parallelepiped shape. The housing 80 includes a first housing 81 that houses the first to fourth solenoid valves 40a to 40d and the motor 50, and a second housing 87 that houses the control board 70. Each surface that constitutes the exterior of the housing 80 may be formed into a shape that includes a stepped portion, a curved portion, or the like.

[0067]

[0046] The first housing 81 is a member attached to the base 60, and for example, a silicone-based sealing material (not shown) is arranged between the first housing 81 and the base 60. The first housing 81 includes an enclosing portion 81a that encloses the first to fourth solenoid valves 40a to 40d and the motor 50 when attached to the base 60, and a connector portion 81b that is formed on the side of the enclosing portion 81a and that houses the connector 75.

[0068]

[0047] When the first housing 81 is attached to the base 60, the surrounding portion 81a includes a first surface 82A facing the base 60 and a second surface 82B facing the control board 70. A first opening 84 is formed on the second surface 82B side of the surrounding portion 81a in an area facing the control board 70. The control board 70 is housed in the surrounding portion 81a through the first opening 84. Furthermore, a second opening 85 facing the first surface 60A of the base 60 is formed on the first surface 82A side of the surrounding portion 81a. The first to fourth coils 42a to 42d and the motor 50 are housed within the surrounding portion 81a through the second opening 85.

[0069]

[0048] The surrounding portion 81a has a through hole 83H through which the above-mentioned bolt 18 is inserted from the first surface 82A side and passes through to the second surface 82B side. When the bolt 18 is inserted into the through hole 83H and engages with the bolt hole 63H in the base 60, the first housing 81 is clamped and fixed between the head of the bolt 18 and the base 60. The surrounding portion 81a also has insertion holes (not shown) through which the electrical terminal 53 of the motor 50 and the electrical terminals 43a to 43d of the first to fourth coils 42a to 42d are inserted from the first surface 82A side and pass through to the second surface 82B side. The bolt 18 that secures the first housing 81 to the base 60 may be one or more, and the bolt holes 63H in the base 60 and the through holes 83H in the first housing 81 may be formed corresponding to the number of bolts. The base 60 and the housing 80 may also be secured together with an adhesive.

[0070]

[0049] The second housing 87 is formed as a separate member from the first housing 81, and when attached to the first housing 81, it covers the control board 70 and closes the first opening 84 of the first housing 81. A silicon-based sealing material mainly composed of silicon is arranged between the first housing 81 and the second housing 87.

[0071] For example, with the second housing 87 having a silicone-based sealant 95 applied to the area facing the edge of the first opening 84 of the first housing 81, the second housing 87 is moved in the attachment direction D and attached to the first housing 81. This bonds the first housing 81 and the second housing 87 together, sealing the gap between the first housing 81 and the second housing 87 and preventing moisture and the like from penetrating into the housing 80 from between the first housing 81 and the second housing 87. In other words, the silicone-based sealant 95 also functions as an adhesive.

[0072]

[0051] The first housing 81 has a protrusion 86 protruding from its outer surface, and the second housing 87 has an engagement portion 88 that engages with the protrusion 86 of the first housing 81 when the second housing 87 is attached to the first housing 81. When the second housing 87 is moved in an attachment direction D (see FIG. 4) for attachment and attached to the first housing 81, the protrusion 86 is inserted into an opening formed in the engagement portion 88 and engages with the engagement portion 88, thereby fixing the second housing 87 to the first housing 81.

[0073] <Regarding the first pump and the second pump> The first pump 27 and the second pump 37, which are mounted on the base 60 and driven by the motor 50, will be described with reference to Fig. 5. Fig. 5 is a cross-sectional view showing the periphery of the first pump 27 mounted on the base 60, taken along a plane perpendicular to the rotation axis of the output shaft 51 of the motor 50. The second pump 37 has the same configuration as the first pump 27, and therefore its description will be omitted. The first pump 27 and the second pump 37 may be collectively referred to simply as pumps.

[0074]

[0053] As described above, the motor 50 includes an output shaft 51 and an eccentric body 52 (see FIG. 4). The output shaft 51 is rotated by a rotor and a stator (not shown) of the motor 50. The eccentric body 52 is provided at one end of the output shaft 51 and rotates eccentrically about the center of rotation of the output shaft 51. A bearing 52a that rotates in the rotational direction of the eccentric body 52 is provided on the outer periphery of the eccentric body 52, and the outer periphery of the bearing 52a presses against the plunger 27e of the first pump 27 to cause it to reciprocate (see FIGS. 4 and 5). The plunger of the second pump 37 is disposed on the axis of the reciprocating motion of the plunger 27e of the first pump 27 so as to face the plunger 27e of the first pump 27 across the eccentric body 52 (not shown).

[0075]

[0054] As shown in FIG. 5, the first pump 27 includes a cylinder 27a disposed in a pump hole 64H formed in the base 60, a plunger 27e, and a spring 27g.

[0076] The cylinder 27a is formed with a compression chamber 27b in which the brake fluid is compressed by the reciprocating motion of a plunger 27e, an inlet hole 27c through which the brake fluid flows into the compression chamber 27b, and an outlet hole 27d through which the brake fluid compressed in the compression chamber 27b flows out. The inlet hole 27c is connected to the first accumulator 26 side of the first sub-fluid passage 23c via a first check valve (not shown) provided in the base 60. The outlet hole 27d is connected to the first main fluid passage 23b side of the first sub-fluid passage 23c via a second check valve (not shown) provided in the base 60. In addition, the cylinder 27a is pressed into the pump hole 64H to seal the pump hole 64H.

[0077]

[0056] One end of plunger 27e abuts against and is pressed by eccentric body 52, and the other end is urged toward eccentric body 52 by spring 27g. When the rotational motion of eccentric body 52 is converted into linear motion, the other end reciprocates within compression chamber 27b, compressing the brake fluid. A seal member 27f (e.g., an O ring) is disposed on the outer circumferential surface of plunger 27e to seal between the outer circumferential surface and the inner circumferential surface of pump hole 64H, thereby preventing brake fluid from leaking from the compression chamber 27b side within pump hole 64H toward eccentric body 52 of motor 50.

[0078]

[0057] The plunger 27e is made of a thermoplastic resin (such as a polyamide synthetic resin) that transitions to a rubbery state when the motor 50 is driven. The thermoplastic resin is, for example, a polyamide synthetic resin having a glass transition point Tg, which is the boundary temperature at which the resin transitions from a glassy state to a rubbery state, of 50 to 80°C. The plunger 27e may be made of any resin that transitions to a rubbery state when the motor 50 is driven. The thermoplastic resin can transition to a rubbery state when the motor 50 is driven by having its glass transition point Tg within the operating temperature range (e.g., room temperature to approximately 140°C) of the pump when the motor 50 is driven. A portion of the plunger 27e of the first pump 27 may be made of the thermoplastic resin.

[0079]

[0058] The first pump 27 operates within a predetermined operating temperature range (for example, room temperature to approximately 140°C) by controlling the operation of the motor 50 using the control board 70. The temperatures of the first pump 27 and the motor 50 rise due to, for example, heat generated when the brake fluid is compressed by the operation of the first pump 27, or heat generated due to copper loss in the motor 50 that drives the first pump 27. The temperatures of the first pump 27 and the motor 50 change depending on the ambient temperature in which the brake fluid pressure control device 10 is used, the magnitude of the load on the first pump 27, the length of continuous operation time of the first pump 27, etc. When the first pump 27 is driven under a relatively high load even within the normal operating range of the brake fluid pressure control device 10, or when the first pump 27 is driven continuously for a relatively long period of time even within the normal operating range, the temperatures of the first pump 27 and the motor 50 may become relatively high (e.g., 80°C) even within the predetermined operating temperature range, and the temperature of the first pump 27 may exceed the glass transition point Tg of the thermoplastic resin that forms the plunger 27e. A similar temperature change occurs in the second pump 37, and the temperature of the second pump 37 may exceed the glass transition point Tg of the thermoplastic resin that forms the plunger.

[0080]

[0059] Here, in an electric motor, the higher the temperature, the higher the electrical resistance of the coils tends to be and the magnetic flux of the magnets tends to be, so the output torque of the motor 50 may decrease due to an increase in its temperature. For example, an increase in the temperature of the motor 50 may cause the output torque of the motor 50 to decrease by approximately 30%. In a conventional brake fluid pressure control device, in preparation for such a decrease in motor output torque due to an increase in temperature, it is necessary to select a motor with a higher maximum output torque even at normal temperatures, which may result in the brake fluid pressure control device and motor becoming larger and more expensive.

[0081] In contrast, the plunger 27e of the first pump 27 of the brake fluid pressure control device 10 of this embodiment is made of a thermoplastic resin whose glass transition point Tg is within the operating temperature range of the first pump 27. Therefore, when the first pump 27 is in a driving state, that is, when the motor 50 is in a driving state, the temperature of the plunger 27e exceeds the glass transition point Tg of the thermoplastic resin, causing at least a part of the plunger 27e to transition to a rubbery state. Note that the plunger 27e returns to a glassy state when the temperature of the first pump 27 falls below the glass transition point Tg of the thermoplastic resin.

[0082] When the plunger 27e is transitioning to the rubbery state, it is more susceptible to deformation due to pressure than before the transition to the rubbery state. For example, the plunger 27e is compressed by being pressed against the eccentric body 52 during the compression stroke of the first pump 27, or by being pressed by the brake fluid pressure, and is deformed so as to shorten the dimension in the axial direction of the reciprocating motion. The higher the brake fluid pressure and the higher the load on the pump, the greater the pressing force acting on the plunger 27e by the eccentric body 52 and the brake fluid, and the greater the deformation of the plunger 27e. For example, when the plunger 27e transitioning to the rubber state is compressed, the axial dimension of the reciprocating motion of the plunger 27e is shortened by 1 mm, thereby shortening the stroke length of the reciprocating motion of the plunger 27e and reducing the output torque of the motor 50 required to drive the first pump 27 by approximately 10%. Furthermore, when the plunger 27e is compressed, the gap between the outer peripheral surface of the plunger 27e and the inner peripheral surface of the pump hole 64H increases, reducing the sliding resistance and fluid resistance of the plunger 27e and reducing the output torque of the motor 50 required to drive the first pump 27.

[0083] As described above, in the first pump 27 of this embodiment, when the motor 50 is driven and the temperature of the motor 50 rises and the output torque decreases, the temperature of the first pump 27 exceeds the glass transition point Tg of the thermoplastic resin of the plunger 27e, thereby shortening the stroke of the plunger 27e and reducing the torque required to drive the first pump 27. As a result, in the brake fluid pressure control device 10, the first pump 27 can be driven by the motor 50, which has a relatively small maximum output torque, and the brake fluid pressure control device and motor can be made smaller and less expensive.

[0084] In this embodiment, one end of the plunger 27e is in direct contact with and pressed by the eccentric body 52. ​​Alternatively, another member that is in contact with and pressed by the eccentric body 52 may be disposed between the plunger 27e and the eccentric body 52, and the plunger 27e may be pressed by the eccentric body 52 via the other member. For example, a steel tappet may be disposed between the plunger 27e and the eccentric body 52, and the plunger 27e may be pressed by the eccentric body 52 via the tappet. With such a configuration, it is possible to reduce deformation of the plunger 27e, which is made of thermoplastic resin, due to a force applied from the eccentric body 52 in a direction intersecting the axis of reciprocating motion. In addition, wear on one end of the plunger 27e can be reduced.

[0085] [ 0 0 6 4 ]

[0086] <Regarding Operation and Effect 1> Conventionally, some straddle-type vehicles (e.g., motorcycles, etc.) have been equipped with brake fluid pressure control devices that control the hydraulic pressure of brake fluid in a brake system that brakes the wheels. One such brake fluid pressure control device is, for example, one that is driven by an electric motor and includes a pump that pumps brake fluid. When the electric motor is in a driven state, it generates heat when current is applied, causing its temperature to rise. As the temperature of the magnets included in the electric motor increases, the magnetic flux density tends to decrease, and the output torque of the electric motor decreases as the temperature of the electric motor increases. When the electric motor is in a driven state, the increase in temperature can cause the output torque of the electric motor to decrease below the torque required to continue rotating the pump. In such a case, the pump may stop rotating, making it difficult for the brake fluid pressure control device to control the brake fluid pressure.

[0087]

[0065] In contrast, the brake fluid pressure control device 10 of this embodiment is a brake fluid pressure control device that controls the hydraulic pressure of brake fluid in a brake system 100 mounted on a motorcycle 1 as a straddle-type vehicle, and includes a base 60 in which a first fluid path 23 that is a fluid path for brake fluid is formed, a first pump 27 that pressurizes the brake fluid in the first fluid path 23, a motor 50 that drives the first pump 27, and a control board 70 that controls the operating state of the motor 50. The motor 50 includes an output shaft 51 and an eccentric body 52 that is provided on the output shaft 51 and rotates eccentrically about the center of rotation of the output shaft 51. The first pump 27 includes the eccentric body 52. The plunger 27e includes a plunger 27e that reciprocates when pressed by the eccentric body 52, and a spring 27g that presses the plunger 27e toward the eccentric body 52. ​​The plunger 27e contains thermoplastic resin, and at least a part of the thermoplastic resin is transformed into a rubber state when the motor 50 is in a driven state.

[0088]

[0066] According to this configuration, in the brake fluid pressure control device 10, the plunger 27e of the first pump 27 contains thermoplastic resin, and when the motor 50 is in a driving state, at least a part of the thermoplastic resin is transformed into a rubber state. Therefore, the plunger 27e that has transformed into the rubber state is compressed by being pressed by the eccentric body 52 and by being exposed to the hydraulic pressure of the brake fluid, and the axial dimension of the reciprocating motion of the plunger 27e is reduced. As a result, when the motor 50 is driven, the stroke of the plunger 27e can be shortened, thereby reducing the torque required to drive the first pump 27. Even if the output torque of the motor 50 decreases as its temperature rises, the first pump 27 can continue to rotate, allowing the brake fluid pressure control device 10 to continue controlling the brake fluid pressure.

[0089] In the brake fluid pressure control device 10 of this embodiment, the plunger 27e of the first pump 27 contains thermoplastic resin, and the thermoplastic resin is polyamide synthetic resin. With this configuration, the plunger 27e can transition to a rubber state when the motor 50 is driven.

[0090]

[0068] The brake fluid pressure control device 10 of this embodiment includes a motor 50 that drives a first pump 27, and the motor 50 is provided on an output shaft 51 and includes an eccentric body 52 that rotates eccentrically about the center of rotation of the output shaft 51, and the eccentric body 52 is configured to include a bearing portion 52a provided on the outer periphery of the eccentric body 52.

[0069] According to this configuration, the eccentric body 52 of the brake fluid pressure control device 10 includes the bearing portion 52a provided on the outer periphery of the eccentric body 52. ​​Therefore, when the rotational motion of the eccentric body 52 is converted into the linear motion of the plunger 27e, the load acting in a direction intersecting the axial direction of the reciprocating motion of the plunger 27e is absorbed by the rotational motion of the bearing portion 52a, and only the load acting in the axial direction of the reciprocating motion of the plunger 27e can be transmitted to the plunger 27e. This reduces deformation of the plunger 27e due to the load from the eccentric body 52 acting in a direction intersecting the axial direction of the reciprocating motion of the plunger 27e.

[0091] The motorcycle 1, which is a straddle-type vehicle according to this embodiment, is configured to include the above-described brake fluid pressure control device 10. With this configuration, the same effects as those of the above-described brake fluid pressure control device 10 can be achieved.

[0092]

[0071] In this embodiment, the plunger 27e of the first pump 27 is configured to contact and be pressed by the eccentric body 52. ​​However, the plunger 27e may be configured to be indirectly pressed by the eccentric body 52. ​​For example, a metal member (such as a tappet) made of a metal material may be disposed between the plunger 27e and the eccentric body 52, and the plunger 27e may be pressed by the eccentric body 52 via the metal member. Alternatively, a resin member may be disposed between the plunger 27e and the eccentric body 52, and the plunger 27e may be pressed by the eccentric body 52 via the resin member. With this configuration, deformation of the plunger 27e due to the load from the eccentric body 52 acting in a direction intersecting the axial direction of the reciprocating motion of the plunger 27e can be reduced.

[0093]

[0072] The brake fluid pressure control device 10 of this embodiment is equipped with a second pump 37 driven by a motor 50. The second pump 37 has the same configuration as the first pump 27 and provides the same effects as the first pump 27.

[0094]

[0073] Although the brake fluid pressure control device 10 according to this embodiment has been described above, the brake fluid pressure control device according to the present invention is not limited to the description of this embodiment. For example, only a part of this embodiment may be implemented.

[0095] [ 0 0 7 4 ]

[0096] Second Embodiment A brake fluid pressure control device according to a second embodiment of the present invention will be described. Note that the configuration of the brake fluid pressure control device of this embodiment includes the same configuration as that of the first embodiment described above, and therefore differences will be mainly described here.

[0097]

[0075] Whereas in the brake fluid pressure control device 10 of the first embodiment described above, the plunger 27e of the first pump 27 is composed of a single member, in the brake fluid pressure control device 10 of the second embodiment, the pump plunger is composed of multiple members. Hereinafter, the pumps of the second embodiment will be referred to as the third pump 200 and the fourth pump 300. Note that the fourth pump 300 has the same configuration as the third pump 200, so a description thereof will be omitted. The third pump 200 and the fourth pump 300 may be collectively referred to simply as pumps.

[0098] [ 0 0 7 6 ]

[0099] <Regarding the third pump and the fourth pump> The third pump 200, which is mounted on the base 60 of the brake fluid pressure control device and driven by the motor 50, will be described with reference to Fig. 6. Fig. 6 is a cross-sectional view showing the periphery of the third pump 200 mounted on the base 60, taken along a plane perpendicular to the rotation axis of the output shaft 51 of the motor 50.

[0100]

[0077] The brake fluid pressure control device 10 is assembled to a base 60 and includes a first fluid passage 23. The first component 221 has an end 221a that reciprocates within the compression chamber 211. The second component 222 is disposed at an end 221b of the first component 221 opposite to the end 221a. The third component 223 has an end 223a that abuts against the eccentric body 52, and the third component 223 is disposed at an end of the second component 222 opposite to the end at which the first component 221 is disposed. The first part 221, the second part 222, and the third part 223 are configured to move integrally. One end 223a of the plunger 220 is in contact with and pressed by the eccentric body 52, and the other end 221a is inserted into the compression chamber 211, so that the plunger 220 reciprocates within the pump hole 64H.

[0101]

[0082] An inflow passage 225 is formed in the first part 221 and the second part 222 of the plunger 220, and guides the brake fluid flowing into the third pump 200 via the inflow hole 224, which communicates with the first sub-fluid path 23c, to the compression chamber 211. A check valve 226 is disposed in the inflow passage 225, which allows the brake fluid to flow from the inflow hole 224 to the compression chamber 211 and restricts the reverse flow, i.e., the flow of brake fluid from the compression chamber 211 to the inflow hole 224. The brake fluid flowing through the first sub-fluid path 23c toward the third pump 200 flows into the compression chamber 211 via the check valve 226 and is compressed.

[0102]

[0083] A sealing member 227 is disposed between the outer peripheral surface of the third part 223 of the plunger 220 and the inner peripheral surface of the pump hole 64H to provide a seal, thereby preventing brake fluid from leaking out through the sealing member 227 toward the eccentric body 52.

[0103]

[0084] The spring 230 is disposed outside the inflow passage 225 and the compression chamber 211, and urges the plunger 220 toward the eccentric body 52. ​​The spring 230 is sandwiched between the cylinder 210 and the first part 221 of the plunger 220 on the outer periphery of the plunger 220, with the spring 230 being shorter than its natural length. By providing the spring 230 outside the inflow passage 225 and the compression chamber 211, the diameter of the spring 230 can be formed to be larger than the diameter of the inflow passage 225. This makes it easy to arrange the spring 230 in the third pump 220, and facilitates the manufacture of the brake fluid pressure control device 10.

[0085] In the third pump 200, the end 223a of the plunger 220 is pressed by the eccentric body 52. ​​As the eccentric body 52 is rotated by the motor 50 and its outer circumferential surface approaches the compression chamber 211, the end 221a of the plunger 220 operates to be inserted into the compression chamber 211, compressing the brake fluid in the compression chamber 211. The compressed brake fluid is then discharged toward the first master cylinder 21 through the first main fluid path 23b. Furthermore, since the plunger 220 is biased by the spring 230, when the outer peripheral surface of the eccentric body 52 moves away from the compression chamber 211, the plunger 220 moves following the outer peripheral surface of the eccentric body 52 with its end 223 a in contact with the eccentric body 52. ​​In other words, the plunger 220 moves following the eccentric rotational motion of the eccentric body 52 and operates to escape from the compression chamber 211, thereby reducing the pressure inside the compression chamber 211 and sucking brake fluid from the first sub-fluid path 23 c and the first accumulator 26.

[0104]

[0086] The first part 221 and the second part 222 of the plunger 220 are made of a thermoplastic resin (such as a polyamide synthetic resin) that transitions to a rubbery state when the motor 50 is driven. The thermoplastic resin is, for example, a polyamide synthetic resin having a glass transition point Tg of 50 to 80°C. The first part 221 and the second part 222 may be made of any resin that transitions to a rubbery state when the motor 50 is driven. The thermoplastic resin can transition to a rubbery state when the motor 50 is driven by having its glass transition point Tg within the operating temperature range of the pump when the motor 50 is driven (for example, room temperature to approximately 140°C). In addition, one of the first part 221 and the second part 222 may be formed from the thermoplastic resin, or a part of the first part 221 or the second part 222 may be formed from the thermoplastic resin.

[0105]

[0087] In the third pump 200 of the brake fluid pressure control device 10 of this embodiment, the first part 221 and the second part 222 of the components of the plunger 220 are configured to be made of a thermoplastic resin whose glass transition point Tg is within the operating temperature range of the third pump 200. Therefore, when the third pump 200 is in a driving state, that is, when the motor 50 is in a driving state, the temperature of the plunger 220 exceeds the glass transition point Tg of the thermoplastic resin, and at least a part of the first part 221 and the second part 222 of the plunger 220 transitions to a rubber state. The first part 221 and the second part 222 transition to a glassy state when the temperature of the third pump 200 drops below the glass transition point Tg of the thermoplastic resin.

[0106]

[0088] When the first component 221 and the second component 222 have transitioned to the rubbery state, they are more susceptible to deformation by pressure than before they transition to the rubbery state. For example, they are compressed by being pressed against the eccentric body 52 during the compression stroke of the third pump 200, or by being pressed by the brake fluid pressure, and are deformed so as to shorten the dimension in the axial direction of the reciprocating motion. The higher the brake fluid pressure and the higher the load on the pump, the greater the pressing force acting on the first component 221 and the second component 222 by the eccentric body 52 and the brake fluid, and the greater the deformation of the plunger 220. For example, when the plunger 220, in which the first part 221 and the second part 222 have transitioned to a rubber state, is compressed, the axial dimension of the reciprocating motion of the plunger 220 becomes shorter by 1 mm, thereby shortening the stroke length of the reciprocating motion of the plunger 220 and making it possible to reduce the output torque of the motor 50 required to drive the third pump 200 by approximately 10%. Furthermore, when the plunger 220 is compressed, the sliding resistance and fluid resistance of the plunger 220 decrease, making it possible to reduce the output torque of the motor 50 required to drive the third pump 200.

[0107] As described above, in the third pump 200 of this embodiment, when the motor 50 is driven and the temperature of the motor 50 rises and the output torque decreases, the temperature of the third pump 200 exceeds the glass transition point Tg of the thermoplastic resin of the first part 221 and the second part 222 that constitute the plunger 220. This shortens the stroke of the plunger 220 and reduces the torque required to drive the third pump 200. As a result, in the brake fluid pressure control device 10, the third pump 200 can be driven by the motor 50, which has a relatively small maximum output torque, and the brake fluid pressure control device and motor can be made smaller and less expensive.

[0108]

[0090] The plunger 220 of the third pump 200 is configured such that the first part 221, the second part 222, and the third part 223 constituting the plunger 220 are made of a thermoplastic resin, but it is sufficient that at least a portion of the plunger 220 is made of the thermoplastic resin. For example, the first part 221, the second part 222, and the third part 223 may all be made of the thermoplastic resin.

[0109]

[0091] The plunger 220 of the third pump 200 is configured such that, of the first part 221, the second part 222, and the third part 223 constituting the plunger 220, the third part 223 that abuts the eccentric body 52 is made of metal. However, the third part 223 may be made of a thermoplastic resin whose glass transition point Tg is higher than the operating temperature range of the third pump 200, that is, a thermoplastic resin that does not transition to a rubbery state when the motor 50 is driven.

[0110] [ 0 0 9 2 ]

[0111] <Regarding operational effects 2> In conventional brake fluid pressure control devices, when the electric motor is in a driving state, the temperature of the electric motor rises, causing the output torque of the electric motor to fall below the torque required to continue rotating the pump, causing the pump to stop rotating, and making it difficult for the brake fluid pressure control device to control the brake fluid pressure.

[0112]

[0093] In contrast, the brake fluid pressure control device 10 of this embodiment is a brake fluid pressure control device that controls the hydraulic pressure of brake fluid in a brake system 100 mounted on a motorcycle 1 as a straddle-type vehicle, and includes a base 60 in which a first fluid path 23 that is a fluid path for brake fluid is formed, a third pump 200 that pressurizes the brake fluid in the first fluid path 23, a motor 50 that drives the third pump 200, and a control board 70 that controls the operating state of the motor 50. The motor 50 includes an output shaft 51 and an eccentric body 52 that is provided on the output shaft 51 and rotates eccentrically about the rotation center of the output shaft 51. The third pump 200 includes the eccentric body 52. The plunger 220 includes a plunger 220 that moves back and forth when pressed by a spring 230, and a spring 230 that presses the plunger 220 toward the eccentric body 52. ​​The plunger 220 includes a first part 221 and a second part 222 that are made of thermoplastic resin, and when the motor 50 is in a driving state, at least a part of the thermoplastic resin of the first part 221 and the second part 222 is transformed into a rubber state.

[0113]

[0094] In the brake fluid pressure control device 10 having such a configuration, the plunger 220 of the third pump 200 includes the first part 221 and the second part 222 made of thermoplastic resin. When the motor 50 is driven, at least a part of the thermoplastic resin of the first part 221 and the second part 222, i.e., at least a part of the plunger 220, is transformed into a rubber state. The plunger 220 that has transformed into the rubber state is compressed by being pressed by the eccentric body 52 and by being exposed to the hydraulic pressure of the brake fluid, and the axial dimension of the reciprocating motion of the plunger 220 is reduced. As a result, when the motor 50 is driven, the stroke of the plunger 220 can be shortened, thereby reducing the torque required to drive the third pump 200. Even if the output torque of the motor 50 decreases as its temperature rises, the rotation of the third pump 200 can be continued, and the brake fluid pressure control device 10 can continue to control the brake fluid pressure.

[0114] In the brake fluid pressure control device 10 of this embodiment, the plunger 220 of the third pump 200 includes a first part 221 and a second part 222 formed from a thermoplastic resin, and the thermoplastic resin is a polyamide synthetic resin. With this configuration, the first part 221 and the second part 222 of the plunger 220 can transition to a rubber state when the motor 50 is driven.

[0115]

[0096] In the brake fluid pressure control device 10 of this embodiment, the plunger 220 of the third pump 200 includes a first part 221 that reciprocates within the compression chamber 211 of the third pump 200, and a third part 223 that is arranged between the first part 221 and the eccentric body 52 and abuts against the eccentric body 52, wherein the first part 221 is made of a thermoplastic resin that transitions to a rubbery state when the motor 50 is driven, and the third part 223 is made of a metal that does not transition to a rubbery state when the motor 50 is driven.

[0116]

[0097] According to this configuration, the third part 223 that comes into contact with the eccentric body 52 is made of metal, and therefore, it is possible to reduce deformation of the plunger 220 due to the load of the eccentric body 52 that acts in a direction intersecting the axial direction of the reciprocating motion of the plunger 220.

[0117]

[0098] In this embodiment, the third part 223 of the plunger 220 of the third pump 200 is made of metal. However, the third part 223 may be made of a thermoplastic resin that does not transition to a rubber state when the motor 50 is driven. Even with this configuration, it is possible to reduce deformation of the plunger 220 due to the load from the eccentric body 52 acting in a direction intersecting the axial direction of the reciprocating motion of the plunger 220.

[0118]

[0099] The brake fluid pressure control device 10 of this embodiment includes a motor 50 that drives a third pump 200. The motor 50 is provided on an output shaft 51 and includes an eccentric body 52 that rotates eccentrically about the center of rotation of the output shaft 51. The eccentric body 52 includes a bearing portion 52a that is provided on the outer periphery of the eccentric body 52.

[0119]

[0100] According to this configuration, the eccentric body 52 of the brake fluid pressure control device 10 includes the bearing portion 52a provided on the outer periphery of the eccentric body 52. ​​Therefore, when the rotational motion of the eccentric body 52 is converted into the linear motion of the plunger 220, the load acting in the direction intersecting the axial direction of the reciprocating motion of the plunger 220 is absorbed by the rotational motion of the bearing portion 52a, and the load acting in the axial direction of the reciprocating motion of the plunger 220 can be transmitted to the plunger 27e. This reduces deformation of the plunger 220 due to the load from the eccentric body 52 acting in the direction intersecting the axial direction of the reciprocating motion of the plunger 22e.

[0120]

[0101] The motorcycle 1, which is a straddle-type vehicle of this embodiment, is configured to include the above-described brake fluid pressure control device 10. With this configuration, the same effects as those of the above-described brake fluid pressure control device 10 can be achieved.

[0121]

[0102] The brake fluid pressure control device 10 of this embodiment is equipped with a fourth pump 300 driven by a motor 50. The fourth pump 300 has the same configuration as the third pump 200 and provides the same effects as the third pump 200.

[0122]

[0103] Although the brake fluid pressure control device 10 according to this embodiment has been described above, the brake fluid pressure control device according to the present invention is not limited to the description of this embodiment. For example, only a part of this embodiment may be implemented.

[0123] [Explanation of symbols]

[0124] [ 0 1 0 4 ]

[0125] 1 Motorcycles (saddle-type vehicles)

[0126] 1 〇 Brake fluid pressure control device 3 First fluid line (fluid line) 7 First pump (pump) 7 e Plunger 7 g Spring 7 Second pump (pump) 〇 Motor (electric motor) 1 Output shaft 2 Eccentric body 〇 Base 〇 Control board 〇 〇 Brake system 〇 〇 Third pump (pump) 2 〇 Plunger 3 〇 Spring 〇 〇 Fourth pump (pump)

Claims

[Document name] Scope of claims

1. A brake fluid pressure control device for controlling a hydraulic pressure of brake fluid in a brake system (100) mounted on a saddle-ride type vehicle (1), comprising: a base (60) in which a hydraulic path (23) of the brake fluid is formed; a pump (27, 200) for pumping the brake fluid in the hydraulic path (23); an electric motor (50) for driving the pump (27, 200); and a control board (70) for controlling an operating state of the electric motor (50), wherein the electric motor (50) comprises an output shaft (51) and an eccentric body (52) provided on the output shaft (51) and rotating eccentrically with respect to a rotation center of the output shaft (51), a plunger (27e, 220) which is pressed by the eccentric body (52) to reciprocate, and a spring (27g, 230) which presses the plunger (27e) toward the eccentric body (52), wherein the plunger (27e, 220) contains a thermoplastic resin, and at least a part of the thermoplastic resin is transformed into a rubber state when the electric motor (50) is in a driving state.

2. The brake fluid pressure control device as described in claim 1, wherein the thermoplastic resin is a polyamide synthetic resin.

3. The brake fluid pressure control device according to claim 1 or 2, wherein the plunger (220) includes a first part (221) that reciprocates within a compression chamber (211) of the pump (200), and a second part (223) that is arranged between the first part (221) and the eccentric body (52) and abuts against the eccentric body, wherein the first part (221) is made of the thermoplastic resin, and the second part (223) is made of a material that does not transition to a rubber state when the electric motor (50) is in a driving state.

4. The brake fluid pressure control device according to claim 3, wherein the second part is made of a synthetic resin that does not transition to a rubber state when the electric motor (50) is in a driving state.

5. The brake fluid pressure control device according to claim 3, wherein the second component (223) is made of a metal material.

6. A brake fluid pressure control device as claimed in claim 1 or 2, wherein the eccentric body (52) is provided with a bearing portion (52a) provided on an outer periphery of the eccentric body (52).

2. A saddle-type vehicle equipped with a brake fluid pressure control device (10) according to claim 1 or 2.

Images