Patent Description:
Some of existing vehicles are equipped with a brake hydraulic pressure control system for causing a brake system to execute an anti-lock braking operation. In a state where a passenger of a vehicle is manipulating an input part such as a brake lever, this brake hydraulic pressure control system amplifies or reduces the pressure of brake fluid inside a brake fluid circuit to adjust a braking force to be generated on wheels. Some of such brake hydraulic pressure control systems are formed by unitizing components such as : a flow channel which constitutes a part of the brake fluid circuit; a motor which is a driving source for a pump device configured to amplify the pressure of brake fluid inside the brake fluid circuit; and a control board for the motor (see <CIT>, for example).

Specifically, the unitized brake hydraulic pressure control system includes: a substrate in which a flow channel for brake fluid is formed; a motor which is a driving source for a pump device provided in the flow channel for brake fluid; a control board for the motor; and a housing which houses therein the control board. The substrate of the brake hydraulic pressure control system substantially has the shape of a rectangular solid, and the housing is attached to one surface thereof. Here, let us assume that the surface of the substrate to which the housing is attached is a first surface, and a surface of the substrate opposed to the first surface is a second surface. When the first surface and the second surface are defined in this manner, in the existing brake hydraulic pressure control systems, the motor which is a driving source for the pump device is attached to the second surface of the substrate. In other words, in the unitized brake hydraulic pressure control system, the motor which is a driving source for the pump device is provided outside the substrate and the housing.

<CIT> describes a brake hydraulic pressure control device with a substrate, a motor for a pump device, a control board of the motor, and a housing of the control board. The motor is a brushless motor. An output shaft of the motor is secured to a rotor of the motor in such a way that both a first end part and a second end part of the output shaft protrude from the rotor, wherein a first bearing is used to rotatably support the output shaft at a position between the first end part and the rotor and a second bearing is used to rotatably support the output shaft at a position between the second end part and the rotor. The first bearing and the second bearing are held by a motor housing. The brake hydraulic pressure control device further includes a detection mechanism which is configured to detect a rotation state of the output shaft.

Further examples of conventional brake hydraulic pressure control devices are disclosed in <CIT> and <CIT>.

A straddle-type vehicle being one type of a vehicle has low flexibility in the layout of components and low flexibility in the installation of a brake hydraulic pressure control system as compared to vehicles such as an automatic four-wheeled vehicle. For this reason, there is a problem of the growing demand for reduction in size of a brake hydraulic pressure control system to be installed in a straddle-type vehicle.

The present invention has been made in view of the above problem. A first objective of the present invention is to achieve a brake hydraulic pressure control system for a straddle-type vehicle which makes it possible to reduce its size as compared to existing ones. In addition, a second objective of the present invention is to achieve a straddle-type vehicle equipped with such a brake hydraulic pressure control system.

The present invention provides a brake hydraulic pressure control system for a straddle-type vehicle with the features of claim <NUM> and a straddle-type vehicle with the features of claim <NUM>.

In the brake hydraulic pressure control system according to the present invention, the motor is disposed in the space surrounded by the substrate and the housing. Accordingly, the brake hydraulic pressure control system according to the present invention makes it possible to reduce its size as compared to existing brake hydraulic pressure control systems.

In the meantime, the motor of the brake hydraulic pressure control system according to the present invention is a brushless motor. Thus, the brake hydraulic pressure control system according to the present invention requires the detection mechanism which is configured to detect the rotation state of the output shaft of the motor. In order for the detection mechanism to accurately detect the rotation state of the output shaft, what is important is the positional accuracy at the time of installing the motor in the space surrounded by the substrate and the housing. Here, the installation space for the motor is limited in the space surrounded by the substrate and the housing. Hence, the brake hydraulic pressure control system according to the present invention positions the motor by inserting the first bearing of the motor into the first concave part of the substrate. The first bearing which is configured to rotatably support the output shaft is originally included in the motor. In other words, the brake hydraulic pressure control system according to the present invention positions the motor using the first bearing originally included in the motor. Accordingly, in the brake hydraulic pressure control system according to the present invention, it is possible to improve the positional accuracy of the motor even in the case of installing the brushless motor in the space surrounded by the substrate and the housing.

Hereinbelow, a brake hydraulic pressure control system and a straddle-type vehicle according to the present invention are described using the drawings.

Note that, although the following description is provided as to a case in which the present invention is employed in two-wheeled motor vehicles, the present invention may be employed in straddle-type vehicles other than the two-wheeled motor vehicles. Examples of the straddle-type vehicles other than the two-wheeled motor vehicles include three-wheeled motor vehicles and buggies using at least one of an engine and an electric motor as its driving source. Other examples of the straddle-type vehicles other than the two-wheeled motor vehicles include bicycles. The bicycles denote all kinds of vehicles capable of driving forward on a road by effort applied to pedals. In other words, the bicycles include normal bicycles, pedal-assisted electric bicycles, electric bicycles, and the like. Meanwhile, the two-wheeled motor vehicles or the three-wheeled motor vehicles denote so-called motorcycles, and the motorcycles include motorbikes, scooters, electric scooters, and the like. Meanwhile, although the following description is provided as to a case in which the brake hydraulic pressure control system includes dual hydraulic circuits, the number of hydraulic circuits in the brake hydraulic pressure control system is not limited to two. The brake hydraulic pressure control system may include only a single hydraulic circuit, or alternatively may include triple or larger-line hydraulic circuits.

In addition, the configuration, operation, and the like described below is one example, and the brake hydraulic pressure control system and the straddle-type vehicle according to the present invention are not limited to the case of having such a configuration, operation, and the like. Moreover, in the drawings, the same reference signs are given to the same or similar members or portions, or no reference signs are given to one or some of the same or similar members or portions. Further, their detailed structures are either illustrated in a simple manner or not described as needed. Furthermore, redundant description is either given in a simple manner or not given as needed.

Hereinbelow, a brake system for a straddle-type vehicle equipped with the brake hydraulic pressure control system according to this embodiment.

The configuration and operation of the brake system according to this embodiment is described.

<FIG> is a view illustrating the configuration of the straddle-type vehicle equipped with the brake system according to the embodiment of the present invention. <FIG> is a view illustrating the configuration of the brake system according to the embodiment of the present invention.

As illustrated in <FIG> and <FIG>, a brake system <NUM> is mounted to a straddle-type vehicle <NUM> such as a two-wheeled motor vehicle. The straddle-type vehicle <NUM> includes: a trunk <NUM>; a handlebar <NUM> which is turnably held by the trunk <NUM>; a front wheel <NUM> which is turnably held by the trunk <NUM> together with the handlebar <NUM>; and a rear wheel <NUM> which is pivotally held by the trunk <NUM>.

The brake system <NUM> includes: a brake lever <NUM>; a first hydraulic circuit <NUM> which is filled with brake fluid; a brake pedal <NUM>; and a second hydraulic circuit <NUM> which is filled with brake fluid. In other words, the brake system <NUM> is equipped with two brake fluid circuits (the first hydraulic circuit <NUM> and the second hydraulic circuit <NUM>). The brake lever <NUM> is provided to the handlebar <NUM> and manipulated by the hands of a user. The first hydraulic circuit <NUM> is configured to apply a brake force, corresponding to the amount of manipulation of the brake lever <NUM>, to a rotor 3a that is configured to rotate together with the front wheel <NUM>. The brake pedal <NUM> is provided below the trunk <NUM> and manipulated by the feet of the user. The second hydraulic circuit <NUM> is configured to apply a brake force, corresponding to the amount of manipulation of the brake pedal <NUM>, to a rotor 4a that is configured to rotate together with the rear wheel <NUM>.

Note that, the brake lever <NUM> and the brake pedal <NUM> are one example of a brake input part. For example, a brake pedal other than the brake pedal <NUM> provided to the trunk <NUM> may be employed as a brake input part instead of the brake lever <NUM>. In addition, for example, a brake lever other than the brake lever <NUM> provided to the handlebar <NUM> may be employed as a brake input part instead of the brake pedal <NUM>. Further, the first hydraulic circuit <NUM> may be configured to apply a brake force, corresponding to the amount of manipulation of the brake lever <NUM> or the amount of manipulation of the brake pedal other than the brake pedal <NUM> provided to the trunk <NUM>, to the rotor 4a that is configured to rotate together with the rear wheel <NUM>. Furthermore, the second hydraulic circuit <NUM> may be configured to apply a brake force, corresponding to the amount of manipulation of the brake pedal <NUM> or the amount of manipulation of the brake lever other than the brake lever <NUM> provided to the handlebar <NUM>, to the rotor 3a that is configured to rotate together with the front wheel <NUM>.

The first hydraulic circuit <NUM> and the second hydraulic circuit <NUM> have the same configuration. Thus, in the following description, the configuration of the first hydraulic circuit <NUM> is described on their behalf.

The first hydraulic circuit <NUM> includes: a master cylinder <NUM> which is embedded with a piston (not illustrated in the drawing) ; a reservoir <NUM> which is attached to the master cylinder <NUM>; a brake caliper <NUM> which is held by the trunk <NUM> and has a brake pad (not illustrated in the drawing); and a wheel cylinder <NUM> which is configured to activate the brake pad (not illustrated in the drawing) of the brake caliper <NUM>.

In the first hydraulic circuit <NUM>, the master cylinder <NUM> and the wheel cylinder <NUM> communicate with each other via: a fluid duct which is connected between the master cylinder <NUM> and a master cylinder port MP formed in a substrate <NUM>; a main flow channel <NUM> which is formed in the substrate <NUM>; and a fluid duct which is connected between the wheel cylinder <NUM> and a wheel cylinder port WP formed in the substrate <NUM>. In addition, a sub-flow channel <NUM> is formed in the substrate <NUM>. Via this sub-flow channel <NUM>, brake fluid inside the wheel cylinder <NUM> is released to a main flow channel midstream part 25a that is a midstream part of the main flow channel <NUM>. Further, in this embodiment, a pressure amplifying flow channel <NUM> is formed in the substrate <NUM>. Via this pressure amplifying flow channel <NUM>, brake fluid inside the master cylinder <NUM> is fed to a sub-flow channel midstream part 26a that is a midstream part of the sub-flow channel <NUM>.

An inlet valve <NUM> is provided to the main flow channel <NUM> in a region closer to the wheel cylinder <NUM> than the main flow channel midstream part 25a. The flow rate of brake fluid passing through this region is controlled by opening and closing operations of the inlet valve <NUM>. To the sub-flow channel <NUM> in a region upstream of the sub-flow channel midstream part 26a, an outlet valve <NUM> and an accumulator <NUM> which is configured to store brake fluid are provided in this order from the upstream side. The flow rate of brake fluid passing through this region is controlled by opening and closing operations of the outlet valve <NUM>. In addition, a pump device <NUM> is provided to the sub-flow channel <NUM> in a region downstream of the sub-flow channel midstream part 26a. A switching valve <NUM> is provided to the main flow channel <NUM> in a region closer to the master cylinder <NUM> than the main flow channel midstream part 25a. The flow rate of brake fluid passing through this region is controlled by opening and closing operations of the switching valve <NUM>. A pressure amplifying valve <NUM> is provided to the pressure amplifying flow channel <NUM>. The flow rate of brake fluid passing through the pressure amplifying flow channel <NUM> is controlled by opening and closing operations of the pressure amplifying valve <NUM>.

Meanwhile, a master cylinder hydraulic pressure sensor <NUM> which is configured to detect the hydraulic pressure of brake fluid inside the master cylinder <NUM> is provided to the main flow channel <NUM> in a region closer to the master cylinder <NUM> than the switching valve <NUM>. In addition, a wheel cylinder hydraulic pressure sensor <NUM> which is configured to detect the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> is provided to the main flow channel <NUM> in a region closer to the wheel cylinder <NUM> than the inlet valve <NUM>.

In other words, the main flow channel <NUM> causes the master cylinder port MP and the wheel cylinder port WP to communicate with each other via the inlet valve <NUM>. In addition, the sub-flow channel <NUM> is a flow channel defined as a part or all of the flow channel which releases brake fluid inside the wheel cylinder <NUM> to the master cylinder <NUM> via the output valve <NUM>. Further, the pressure amplifying flow channel <NUM> is a flow channel defined as a part or all of the flow channel which feeds brake fluid inside the master cylinder <NUM> to the sub-flow channel <NUM>, at a position upstream of the pump device <NUM>, via the pressure amplifying valve <NUM>.

The inlet valve <NUM> is an electromagnetic valve which is configured to switch, when changed from de-energized to energized state for example, its mode from opening to closing of passage of brake fluid flowing through its installed position. The outlet valve <NUM> is an electromagnetic valve which is configured to switch, when changed from de-energized to energized state for example, its mode from closing to opening of passage of brake fluid flowing through its installed position toward the sub-flow channel midstream part 26a. The switching valve <NUM> is an electromagnetic valve which is configured to switch, when changed from de-energized to energized state for example, its mode from opening to closing of passage of brake fluid flowing through its installed position. The pressure amplifying valve <NUM> is an electromagnetic valve which is configured to switch, when changed from de-energized to energized state for example, its mode from closing to opening of passage of brake fluid flowing through its installed position toward the sub-flow channel midstream part 26a.

The pump device <NUM> of the first hydraulic circuit <NUM> and the pump device <NUM> of the second hydraulic circuit <NUM> are driven by a shared motor <NUM>. In other words, the motor <NUM> is a driving source for these pump devices <NUM>.

The substrate <NUM>, the components provided to the substrate <NUM> (such as the inlet valve <NUM>, the outlet valve <NUM>, the accumulator <NUM>, the pump device <NUM>, the switching valve <NUM>, the pressure amplifying valve <NUM>, the master cylinder hydraulic pressure sensor <NUM>, the wheel cylinder hydraulic pressure sensor <NUM>, and the motor <NUM>), and a control unit (ECU) <NUM> constitute a brake hydraulic pressure control system <NUM>. Note that, in this embodiment, the components such as the inlet valve <NUM>, the outlet valve <NUM>, the accumulator <NUM>, the pump device <NUM>, the switching valve <NUM>, the pressure amplifying valve <NUM>, the master cylinder hydraulic pressure sensor <NUM>, the wheel cylinder hydraulic pressure sensor <NUM>, and the motor <NUM> are sometimes collectively referred to as a brake fluid hydraulic pressure control mechanism. In other words, the brake fluid hydraulic pressure control mechanism is a mechanism used for controlling the hydraulic pressure of brake fluid in the first hydraulic circuit <NUM> and the second hydraulic circuit <NUM>.

The number of the control unit <NUM> may be one or more than one. In addition, the control unit <NUM> may be attached to the substrate <NUM>, or alternatively may be attached to a member other than the substrate <NUM>. In addition, for example, a part or all of the control unit <NUM> may be constituted of a component such as a microcomputer and a microprocessor unit, or alternatively may be constituted of an updatable component such as firmware, or alternatively may be a program module and the like executed by commands from a CPU and the like.

Note that, as is to be described later, in the brake hydraulic pressure control system <NUM> according to this embodiment, at least a part of the control unit <NUM> is constituted of a control board <NUM>. In addition, in this embodiment, the control board <NUM> has a function to control start, stop, and the like of the motor <NUM>. In other words, it is possible to say that the brake hydraulic pressure control system <NUM> according to this embodiment includes the control board <NUM> for the motor <NUM>. Besides, in this embodiment, the control board <NUM> also performs control over the components constituting the brake fluid hydraulic pressure control mechanism. In other words, it is also possible to say that the brake hydraulic pressure control system <NUM> according to this embodiment includes the control board <NUM> for the brake fluid hydraulic pressure control mechanism.

For example, in a normal state, the inlet valve <NUM>, the output valve <NUM>, the switching valve <NUM>, and the pressure amplifying valve <NUM> are controlled to be de-energized by the control unit <NUM>. When the brake lever <NUM> is manipulated in this state, in the first hydraulic circuit <NUM>, the piston (not illustrated in the drawing) of the master cylinder <NUM> is depressed to amplify the hydraulic pressure of brake fluid inside the wheel cylinder <NUM>, whereby the brake pad (not illustrated in the drawing) of the brake caliper <NUM> is pressed against the rotor 3a of the front wheel <NUM> to brake the front wheel <NUM>. Meanwhile, when the brake pedal <NUM> is manipulated, in the second hydraulic circuit <NUM>, the piston (not illustrated in the drawing) of the master cylinder <NUM> is depressed to amplify the hydraulic pressure of brake fluid inside the wheel cylinder <NUM>, whereby the brake pad (not illustrated in the drawing) of the brake caliper <NUM> is pressed against the rotor 4a of the rear wheel <NUM> to brake the rear wheel <NUM>.

Outputs from the various sensors (such as the master cylinder hydraulic pressure sensor <NUM>, the wheel cylinder hydraulic pressure sensor <NUM>, a wheel speed sensor, and an acceleration sensor) are input to the control unit <NUM>. In response to such outputs, the control unit <NUM> outputs commands, controlling the operations of the motor <NUM>, the valves, and the like, to execute a pressure reducing control operation, a pressure amplifying control operation, and the like.

For example, when the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the first hydraulic circuit <NUM> is excessive or likely to be excessive, the control unit <NUM> executes an operation to reduce the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the first hydraulic circuit <NUM>. In this event, in the first hydraulic circuit <NUM>, the control unit <NUM> drives the motor <NUM> while performing control to energize the inlet valve <NUM>, to energize the outlet valve <NUM>, to de-energize the switching valve <NUM>, and to de-energize the pressure amplifying valve <NUM>. Meanwhile, when the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the second hydraulic circuit <NUM> is excessive or likely to be excessive, the control unit <NUM> executes an operation to reduce the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the second hydraulic circuit <NUM>. In this event, in the second hydraulic circuit <NUM>, the control unit <NUM> drives the motor <NUM> while performing control to energize the inlet valve <NUM>, to energize the outlet valve <NUM>, to de-energize the switching valve <NUM>, and to de-energize the pressure amplifying valve <NUM>.

Thereby, the brake hydraulic pressure control system <NUM> is capable of executing an anti-lock braking operation of the first hydraulic circuit <NUM> by controlling the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the first hydraulic circuit <NUM>. In addition, the brake hydraulic pressure control system <NUM> is capable of executing an anti-lock braking operation of the second hydraulic circuit <NUM> by controlling the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the second hydraulic circuit <NUM>. In other words, the motor <NUM> which is the driving source for the pump devices <NUM> is driven at least at the time of decreasing the hydraulic pressures of the first hydraulic circuit <NUM> and the second hydraulic circuit <NUM>. To put it another way, the pump devices <NUM> are configured to decrease at least the hydraulic pressures of the first hydraulic circuit <NUM> and the second hydraulic circuit <NUM>.

On the other hand, for example, when the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the first hydraulic circuit <NUM> is deficient or likely to be deficient, the control unit <NUM> executes an operation to amplify the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the first hydraulic circuit <NUM>. In this event, in the first hydraulic circuit <NUM>, the control unit <NUM> drives the motor <NUM> while performing control to de-energize the inlet valve <NUM>, to de-energize the outlet valve <NUM>, to energize the switching valve <NUM>, and to energize the pressure amplifying valve <NUM>. Meanwhile, when the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the second hydraulic circuit <NUM> is deficient or likely to be deficient, the control unit <NUM> executes an operation to amplify the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the second hydraulic circuit <NUM>. In this event, in the second hydraulic circuit <NUM>, the control unit <NUM> drives the motor <NUM> while performing control to de-energize the inlet valve <NUM>, to de-energize the outlet valve <NUM>, to energize the switching valve <NUM>, and to energize the pressure amplifying valve <NUM>.

Thereby, the brake hydraulic pressure control system <NUM> is capable of executing an automatic pressure amplifying operation of the first hydraulic circuit <NUM> by controlling the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the first hydraulic circuit <NUM>. In addition, the brake hydraulic pressure control system <NUM> is capable of executing an automatic pressure amplifying operation of the second hydraulic circuit <NUM> by controlling the hydraulic pressure of brake fluid inside the wheel cylinder <NUM> of the second hydraulic circuit <NUM>.

In the brake hydraulic pressure control system <NUM>, the substrate <NUM>, the motor <NUM>, and the control board <NUM> are unitized. Note that, in this embodiment, the components other than the motor <NUM> which are provided to the substrate <NUM> (such as the inlet valve <NUM>, the outlet valve <NUM>, the accumulator <NUM>, the pump device <NUM>, the switching valve <NUM>, the pressure amplifying valve <NUM>, the master cylinder hydraulic pressure sensor <NUM>, and the wheel cylinder hydraulic pressure sensor <NUM>) are also unitized with the substrate <NUM> and the control board <NUM>. In the following description, the configuration of the unitized portion of the brake hydraulic pressure control system <NUM> is described.

<FIG> is a view illustrating, as seen from above, the unitized portion of the brake hydraulic pressure control system according to the embodiment of the present invention in a state where the unitized portion of the brake hydraulic pressure control system according to the embodiment of the present invention is mounted to the straddle-type vehicle, a part of which is illustrated by cross section.

The substrate <NUM> described above is formed of metal such as aluminum, and has the shape of a substantially rectangular solid, for example. This substrate <NUM> includes a first surface 80a and a second surface 80b. A housing <NUM> is connected to the first surface 80a. In addition, the control board <NUM> is housed in the housing <NUM>. The second surface 80b is the opposite surface of the first surface 80a. Note that, the surfaces of the substrate <NUM> may include a stepped portion or a curved portion.

The motor <NUM> is attached to the substrate <NUM>. This motor <NUM> includes: a stator <NUM>; a rotor <NUM>; an output shaft <NUM>; a bearing <NUM>; a bearing <NUM>; and a motor housing <NUM>. A substantially cylindrical through hole is formed in the stator <NUM>. The rotor <NUM> has a substantially cylindrical shape, and is disposed inside the through hole of the stator <NUM> so as to be rotatable with respect to the stator <NUM>. The output shaft <NUM> is secured to this rotor <NUM>. The output shaft <NUM> is secured to the rotor <NUM> in such a way that both an end part 45a and an end part 45b of the output shaft <NUM> protrude from the rotor <NUM>.

The bearing <NUM> is configured to rotatably support the output shaft <NUM> at a position between the end part 45a and the rotor <NUM>. The bearing <NUM> is configured to rotatably support the output shaft <NUM> at a position between the end part 45b and the rotor <NUM>. The motor housing <NUM> constitutes the outline of the motor <NUM>. In this embodiment, the motor housing <NUM> includes: a metal part 50a which is formed of metal; and a resin part 50b which is formed of a material containing resin. The metal part 50a is formed by sheet metal machining, for example, while the resin part 50b is formed by molding, for example. The stator <NUM> and the rotor <NUM> are housed in the motor housing <NUM>. In addition, the motor housing <NUM> holds the bearing <NUM> and the bearing <NUM>. Specifically, the bearing <NUM> is held by the resin part 50b, while the bearing <NUM> is held by the metal part 50a. Further, in this embodiment, the bearing <NUM> is held by the motor housing <NUM> in such a way that a part of the bearing <NUM> protrudes from the motor housing <NUM> toward the end part 45a of the output shaft <NUM>.

Here, existing motors include a pair of bearings (corresponding to the bearing <NUM> and the bearing <NUM> according to this embodiment) which rotatably support an output shaft. In addition, in the existing motors, the output shaft is loosely fitted to at least one of the pair of bearings with a clearance therebetween. As in the case of the existing motors, in the motor <NUM> according to this embodiment, when the output shaft <NUM> is fitted to the bearing <NUM> and the bearing <NUM>, the output shaft <NUM> is loosely fitted to at least one of the bearing <NUM> and the bearing <NUM> with a clearance therebetween. Specifically, in this embodiment, the output shaft <NUM> of the motor <NUM> is tightly fitted to the bearing <NUM> with no clearance therebetween, and is loosely fitted to the bearing <NUM> with a clearance therebetween.

The motor <NUM> according to this embodiment is a brushless motor. By using a brushless motor as the motor <NUM>, it is possible to make the brake hydraulic pressure control system <NUM> longer lasting as compared to the case of using a brushed motor as the motor <NUM>. In this embodiment, since the motor <NUM> is a brushless motor, the stator <NUM> includes a coil <NUM>. In addition, the coil <NUM> is connected to the control board <NUM> with wires, terminals, or the like (not illustrated in the drawing). When power is supplied to the coil <NUM> from the control board <NUM>, electric current flows through the coil <NUM>, whereby a magnetic field is generated. The action of this magnetic field on the rotor <NUM> makes the rotor <NUM> and the output shaft <NUM> rotate about a rotational axis 45c. Then, the rotation of the rotor <NUM> and the output shaft <NUM> drives the pump device <NUM> in the following way.

The pump device <NUM> includes a piston 31a which is configured to perform a translatory reciprocating movement. In addition, an eccentric body <NUM> which is configured to bear an end part of the piston 31a is attached to the output shaft <NUM> of the motor <NUM> in a region between a portion of the output shaft supported by the bearing <NUM> and the end part 45a. The central axis of the eccentric body <NUM> is eccentric with respect to the rotational axis 45c. Thereby, when the eccentric body <NUM> rotates together with the rotor <NUM> and the output shaft <NUM>, the piston 31a of the pump device <NUM> that is pressed against the outer circumferential surface of the eccentric body <NUM> performs a reciprocating movement, whereby brake fluid is conveyed from the inlet side toward the outlet side of the pump device <NUM>.

Note that, the motor <NUM> may have a configuration other than the configuration described above. For example, the motor <NUM> may have such a configuration that the motor includes multiple gears such as planetary gears, and the output shaft <NUM> and the eccentric body <NUM> are connected to each other via these gears. Alternatively, for example, the motor <NUM> may include a cover, which covers the configuration of the motor <NUM>, at a position outside the motor housing <NUM>.

Here, in existing brake hydraulic pressure control systems, a motor which is a driving source of a pump device is attached to a second surface of a substrate. In other words, in the existing brake hydraulic pressure control systems, the motor which is a driving source of the pump device is provided outside the substrate and the housing. On the other hand, in the brake hydraulic pressure control system <NUM> according to this embodiment, the motor <NUM> is attached to the first surface 80a of the substrate <NUM>. Thereby, in a state in which the housing <NUM> is connected to the substrate <NUM>, the motor <NUM> is disposed in a space surrounded by the substrate <NUM> and the housing <NUM>. By installing the motor <NUM> in this manner, it is possible to reduce the size of the brake hydraulic pressure control system <NUM> as compared to the existing brake hydraulic pressure control systems.

In addition, in this embodiment, a region of the output shaft <NUM> between the portion where the eccentric body <NUM> is attached and the end part 45a is free. To put it another way, the region of the output shaft <NUM> between the portion where the eccentric body <NUM> is attached and the end part 45a is not supported by any bearing. Thereby, it is not necessary to prepare a space for installing such a bearing in the substrate <NUM>, whereby the brake hydraulic pressure control system <NUM> can be further reduced in size.

Further, in the existing brake hydraulic pressure control systems, the motor is secured to the substrate by being fastened thereto with bolts. Specifically, in the existing brake hydraulic pressure control systems, multiple through holes are formed in a flange part of the motor, and the bolts are inserted into the respective through holes. Meanwhile, in the existing brake hydraulic pressure control systems, multiple female screw parts are formed in the substrate. Thus, in the existing brake hydraulic pressure control systems, the motor is secured to the substrate in such a way that the bolts inserted in the through holes of the flange part of the motor are respectively screwed into the female screw parts of the substrate and thereby the flange part of the motor is pinched between the heads of the bolts and the substrate.

In the brake hydraulic pressure control system <NUM> according to this embodiment, the motor <NUM> may also be secured to the substrate <NUM> by fastening with bolts as in the case of the existing systems. However, in this embodiment, the motor <NUM> is secured to the substrate <NUM> by so-called crimping. Here, the direction of the rotational axis 45c of the output shaft <NUM> is assumed as the direction of thrust. A portion where the motor <NUM> is secured to the substrate <NUM> by crimping mainly bears a load in the direction of thrust. Specifically, the motor housing <NUM> of the motor <NUM> includes a flange <NUM> which protrudes outward. More specifically, the metal part 50a of the motor housing <NUM> includes the flange <NUM> which protrudes outward. A concave part <NUM> into which the flange <NUM> is inserted is formed in the substrate <NUM>. Note that, a bottom part <NUM> of the concave part <NUM> may include a stepped portion or a curved portion. As described above, in this embodiment, the motor <NUM> is disposed in the space surrounded by the substrate <NUM> and the housing <NUM>. Thus, the concave part <NUM> is open toward the housing <NUM>. In addition, a plastic deformation part <NUM> is formed in the inner circumferential surface of the concave part <NUM>. The plastic deformation part <NUM> according to this embodiment is a stepped part such that the inner circumferential surface of the concave part <NUM> is shifted in a direction away from the outer circumferential surface of the motor <NUM>. For example, the plastic deformation part <NUM> is disposed in the inner circumferential surface of the concave part <NUM> at a pitch of <NUM> degrees.

When the motor <NUM> is secured to the substrate <NUM>, the flange <NUM> of the motor housing <NUM> is inserted into the concave part <NUM> so that the eccentric body <NUM> attached to the output shaft <NUM> is located inside the substrate <NUM>. Moreover, the flange <NUM> of the motor housing <NUM> is inserted into the concave part <NUM> until the flange is brought into contact with the bottom part <NUM> of the concave part <NUM>. In this state, a jig is inserted into a space of the plastic deformation part <NUM> of the concave part <NUM> on the first surface 80a side, and the plastic deformation part <NUM> is plastic deformed by application of pressure. In this way, the motor <NUM> is secured to the substrate <NUM> in such a way that the flange <NUM> of the motor housing <NUM> is pinched between the plastic deformation part <NUM>, formed in the inner circumferential surface of the concave part <NUM>, and the bottom part <NUM> of the concave part <NUM>. By securing the motor <NUM> to the substrate <NUM> by crimping in this manner, it is not necessary to prepare bolts for securing the motor <NUM>, and also not necessary to form female screw parts, into which the bolts are screwed, in the substrate <NUM>. Accordingly, the brake hydraulic pressure control system <NUM> can be further reduced in size.

In the meantime, in the case of using a brushless motor, a detection mechanism which is configured to detect the rotation state of an output shaft of the brushless motor is heretofore provided. The brake hydraulic pressure control system <NUM> according to this embodiment also includes a detection mechanism <NUM> for detecting the rotation state of the output shaft <NUM> of the motor <NUM> which is a brushless motor. Specifically, in this embodiment, the detection mechanism <NUM> is used to detect the rotation position and the rotation speed of the output shaft <NUM> as the rotation state of the output shaft <NUM>.

The detection mechanism <NUM> includes: a rotation element <NUM> which is configured to rotate together with the output shaft <NUM>; and a sensor <NUM> which is configured to detect the rotation position of the rotation element <NUM>. Various rotation elements having been used in existing detection mechanisms can be used as the rotation element <NUM>. Likewise, various sensors having been used in existing detection mechanisms can be used as the sensor <NUM>. For example, a permanent magnet can be used as the rotation element <NUM>. In this case, a sensor using a Hall element can be used as the sensor <NUM>, for example. Alternatively, for example, a disc having a through hole formed therein or a disc to which a reflector plate is mounted can be used as the rotation element <NUM>. In this case, a sensor using a light emitting element and a light receiving element can be used as the sensor <NUM>, for example.

In order for the detection mechanism <NUM> to accurately detect the rotation state of the output shaft <NUM>, what is important is the positional accuracy at the time of installing the motor <NUM> in the space surrounded by the substrate <NUM> and the housing <NUM>. Here, the installation space for the motor <NUM> is limited in the space surrounded by the substrate <NUM> and the housing <NUM>. To deal with this, in this embodiment, the motor <NUM> is disposed in the space surrounded by the substrate <NUM> and the housing <NUM> in the following way.

A concave part <NUM> which is open toward the housing <NUM> is formed in the substrate <NUM>. In this embodiment, the concave part <NUM> is formed in the bottom part <NUM> of the concave part <NUM>. In addition, the bearing <NUM> of the motor <NUM> is inserted into the concave part <NUM>. Specifically, as described above, the bearing <NUM> is held by the motor housing <NUM> in such a way that a part of the bearing <NUM> protrudes from the motor housing <NUM> toward the end part 45a of the output shaft <NUM>, and the part of the bearing <NUM> protruding from the motor housing <NUM> is inserted into the concave part <NUM>. The bearing <NUM> which is configured to rotatably support the output shaft <NUM> is originally a member included in the motor <NUM>. In other words, the brake hydraulic pressure control system <NUM> according to this embodiment positions the motor <NUM> using the bearing <NUM> originally included in the motor <NUM>. Accordingly, in the brake hydraulic pressure control system <NUM> according to this embodiment, it is possible to improve the positional accuracy of the motor <NUM> even in the case of installing the motor <NUM> in the space surrounded by the substrate <NUM> and the housing <NUM>.

Further, in this embodiment, the bearing <NUM> is fitted into the concave part <NUM>. With such a configuration, it is possible to further improve the positional accuracy of the motor <NUM>. In addition, such a configuration can also bring about the following effect. When the pump device <NUM> is driven, a load from the piston 31a of the pump device <NUM> acts on the output shaft <NUM> of the motor <NUM> which is a driving source of the pump device <NUM> via the eccentric body <NUM>. Since the bearing <NUM> is fitted into the concave part <NUM>, a region between the bearing <NUM> and the concave part <NUM> can also bear this load in addition to the portion where the motor <NUM> is secured to the substrate <NUM> by crimping. Accordingly, since the bearing <NUM> is fitted into the concave part <NUM>, it is possible to improve the reliability of the brake hydraulic pressure control system <NUM>. In addition, in this embodiment, the bearing <NUM> is loosely fitted into the concave part <NUM> with a clearance therebetween. With such a configuration, it is possible to fit the bearing <NUM> into the concave part <NUM> easily, and thus reduce the number of man-hours for assembling the brake hydraulic pressure control system <NUM>.

Note that, the output shaft <NUM> of the motor <NUM> may be tightly fitted to the bearing <NUM> with no clearance therebetween as well as being tightly fitted to the bearing <NUM> with no clearance therebetween. Thereby, it is possible to inhibit the runout of the output shaft <NUM> from occurring when a load acts on the output shaft <NUM> at the time of driving the pump device <NUM>. In other words, the runout of the rotation element <NUM> that rotates together with the output shaft <NUM> is also inhibited. Accordingly, it is possible to detect the rotation state of the output shaft <NUM> further accurately.

In addition, in this embodiment, the rotation element <NUM> is located between the output shaft <NUM> and the control board <NUM>. Specifically, in this embodiment, the rotation element <NUM> is attached to the end part 45b of the output shaft <NUM>. Since the rotation element <NUM> is located between the output shaft <NUM> and the control board <NUM>, it is possible to mount the sensor <NUM> to the control board <NUM>. This makes it unnecessary to provide an additional control board other than the control board <NUM> for mounting the sensor <NUM> thereto, whereby the brake hydraulic pressure control system <NUM> can be further reduced in size.

In the meantime, those skilled in the art having known the brake hydraulic pressure control system <NUM> according to this embodiment might be concerned about an excessive temperature increase of the coil <NUM> of the motor <NUM> by the installation of the motor <NUM> in the space surrounded by the substrate <NUM> and the housing <NUM>. However, the brake hydraulic pressure control system <NUM> according to this embodiment can suppress a temperature increase of the coil <NUM> of the motor <NUM>. Specifically, as described above, the stator <NUM> of the motor <NUM> includes the coil <NUM>. In addition, the stator <NUM> of the brake hydraulic pressure control system <NUM> according to this embodiment includes a mold part <NUM> which covers the coil <NUM> with a mold member. Further, this mold part <NUM> is in contact with the motor housing <NUM>. In this embodiment, the mold part <NUM> is in contact with both the metal part 50a and the resin part 50b of the motor housing <NUM>. The motor housing <NUM> is surely in contact with some sort of object other than the mold part <NUM>. For this reason, in the brake hydraulic pressure control system <NUM> according to this embodiment, heat generated by the coil <NUM> is transmitted to the object, which is in contact with the motor housing <NUM>, by way of the mold part <NUM> and the motor housing <NUM>.

The coil <NUM> has a substantially circular shape in cross section. For this reason, in the case of not including the mold part <NUM>, even if the outer circumferential surface of the coil <NUM> and the motor housing <NUM> are in contact with each other, the area of contact between the coil <NUM> and the motor housing <NUM> is small. Specifically, when the cross section of the coil <NUM> is observed, the coil <NUM> having a substantially circular shape in cross section and the motor housing <NUM> are in point contact with each other. For this reason, in the case of not including the mold part <NUM>, even if the outer circumferential surface of the coil <NUM> and the motor housing <NUM> are in contact with each other, the amount of heat transmitted from the coil <NUM> to the motor housing <NUM> is small. On the other hand, in the case of including the mold part <NUM>, the mold part <NUM> can be in contact with a larger area of the outer circumferential surface of the coil <NUM>. In addition, the mold part <NUM> can be in contact with a larger area of the motor housing <NUM> than the area of contact in the case where the coil <NUM> and the motor housing <NUM> are in direct contact with each other.

For this reason, by including the mold part <NUM>, it is possible to increase the amount of heat transmitted from the coil <NUM> to the motor housing <NUM> as compared to the case where the coil <NUM> and the motor housing <NUM> are in direct contact with each other. Thus, by including the mold part <NUM>, it is possible to transmit heat generated by the coil <NUM> sufficiently to the object, which is in contact with the motor housing <NUM>, by way of the mold part <NUM> and the motor housing <NUM>. Accordingly, by including the mold part <NUM>, it is possible to discharge heat generated by the coil <NUM> to outside the space surrounded by the substrate <NUM> and the housing <NUM>, and thereby suppress a temperature increase of the coil <NUM> of the motor <NUM>.

Note that, a specific kind of the mold member of the mold part <NUM> is not particularly limited. For example, a material such as glass or metal can be used as the mold member. Alternatively, a material containing resin may also be used as the mold member, for example. In this embodiment, resin containing glass fiber is used as the mold member of the mold part <NUM>. Molding of the mold part <NUM> becomes easier by using a material containing resin as the mold member of the mold part <NUM>. Note that, in this embodiment, the mold part <NUM> and the resin part 50b of the motor housing <NUM> are molded into one unit.

Here, in this embodiment, the motor housing <NUM> is in contact with the substrate <NUM>. The substrate <NUM> is a component relatively large in size among the components constituting the brake hydraulic pressure control system <NUM>. In addition, the substrate <NUM> is made of metal. Thus, since the motor housing <NUM> is in contact with the substrate <NUM>, it becomes easier to discharge heat generated by the coil <NUM> to outside the space surrounded by the substrate <NUM> and the housing <NUM>, whereby a temperature increase of the coil <NUM> of the motor <NUM> can be further suppressed.

Further, in this embodiment, as described above, the bearing <NUM> held by the motor housing <NUM> is in contact with the substrate <NUM>. For this reason, in the brake hydraulic pressure control system <NUM> according to this embodiment, heat generated by the coil <NUM> can be transmitted to the substrate <NUM> also by way of a path passing through the mold part <NUM>, the motor housing <NUM>, and the bearing <NUM>. Accordingly, the brake hydraulic pressure control system <NUM> according to this embodiment can further suppress a temperature increase of the coil <NUM> of the motor <NUM>.

In the meantime, the brake hydraulic pressure control system <NUM> according to this embodiment includes at least one plate spring <NUM>. The brake hydraulic pressure control system <NUM> according to this embodiment grounds the control board <NUM> using the plate spring <NUM> to suppress the electrostatic charging of the control board <NUM>. Hereinbelow, the configuration of the plate spring <NUM> and therearound is described using <FIG> and <FIG> and <FIG> to be described later.

<FIG> is an enlarged view of a portion A of <FIG>. Meanwhile, <FIG> is a view as seen in the direction of the arrow B in <FIG>. In other words, <FIG> is a view illustrating, as seen from above, the plate spring <NUM> and therearound in the unitized portion of the brake hydraulic pressure control system <NUM> in a state where the unitized portion of the brake hydraulic pressure control system <NUM> is mounted to the straddle-type vehicle <NUM>. Meanwhile, <FIG> is a view illustrating, as seen in the transverse direction, the plate spring <NUM> and therearound in the unitized portion of the brake hydraulic pressure control system <NUM> in a state where the unitized portion of the brake hydraulic pressure control system <NUM> is mounted to the straddle-type vehicle <NUM>.

The plate spring <NUM> is made of metal. Note that, the material of the plate spring <NUM> is not limited to metal as long as it is conductive, and may be a material such as fiber-reinforced resin. Here, the brake hydraulic pressure control system <NUM> includes a component which is disposed in the space surrounded by the substrate <NUM> and the housing <NUM> and is electrically connected to the substrate <NUM>. Hereinbelow, the component which is disposed in the space surrounded by the substrate <NUM> and the housing <NUM> and is electrically connected to the substrate <NUM> is referred to as an electrically connected component. When the electrically connected component is defined in the above manner, the plate spring <NUM> is provided between the control board <NUM> and the electrically connected component. Note that, examples of the electrically connected component include pistons of the inlet valve <NUM>, the outlet valve <NUM>, the switching valve <NUM>, and the pressure amplifying valve <NUM>. In addition, another example of the electrically connected component is the motor housing <NUM>. In this embodiment, the plate spring <NUM> is provided between the control board <NUM> and the motor housing <NUM>. Hereinbelow, the detailed configuration of the plate spring <NUM> is described using the motor housing <NUM> as an example of the electrically connected component.

The plate spring <NUM> is expandable and contractable in a direction in which the control board <NUM> and the motor housing <NUM> are opposed to each other. In addition, the free length of the plate spring <NUM> is longer than the distance between the control board <NUM> and the motor housing <NUM>. To put it differently, the plate spring <NUM> is compressed between the control board <NUM> and the motor housing <NUM>. Besides, an end part <NUM> of the plate spring <NUM> is connected to the control board <NUM>, whereas an end part <NUM> of the plate spring <NUM> is connected to the motor housing <NUM>. Specifically, in this embodiment, the end part <NUM> of the plate spring <NUM> is connected to the metal part 50a of the motor housing <NUM>.

Concretely, the end part <NUM> of the plate spring <NUM> is electrically connected to the control board <NUM>. In addition, since soldered to the control board <NUM>, the end part <NUM> of the plate spring <NUM> is connected to the control board <NUM> also mechanically. Note that, the state where the end part <NUM> of the plate spring <NUM> is connected to the control board <NUM> includes not only a state where the end part <NUM> of the plate spring <NUM> is directly connected to the control board <NUM> but also a state where the end part <NUM> of the plate spring <NUM> is indirectly connected to the control board <NUM>. For example, in order to allow the end part <NUM> of the plate spring <NUM> and the control board <NUM> to be electrically connected to each other reliably for a long period of time, it is conceivable to provide a member formed of a material not easily oxidized, such as silver, between the end part <NUM> of the plate spring <NUM> and the control board <NUM>. In this case, in this embodiment, the end part <NUM> of the plate spring <NUM> is also referred to as being connected to the control board <NUM>.

In addition, the end part <NUM> of the plate spring <NUM> is electrically connected to the motor housing <NUM>. Note that, the state where the end part <NUM> of the plate spring <NUM> is connected to the motor housing <NUM> includes not only a state where the end part <NUM> of the plate spring <NUM> is directly connected to the motor housing <NUM> but also a state where the end part <NUM> of the plate spring <NUM> is indirectly connected to the motor housing <NUM>. For example, in order to allow the end part <NUM> of the plate spring <NUM> and the motor housing <NUM> to be electrically connected to each other reliably for a long period of time, it is conceivable to provide a member formed of a material not easily oxidized, such as silver, between the end part <NUM> of the plate spring <NUM> and the motor housing <NUM>. In this case, in this embodiment, the end part <NUM> of the plate spring <NUM> is also referred to as being connected to the motor housing <NUM>.

In other words, in the brake hydraulic pressure control system <NUM> according to this embodiment, the control board <NUM> is electrically connected to the substrate <NUM> via the plate spring <NUM> and the motor housing <NUM>. This enables the brake hydraulic pressure control system <NUM> according to this embodiment to ground the control board <NUM>, and thereby suppress the electrostatic charging of the control board <NUM>.

Here, some of existing brake hydraulic pressure control systems proposed ground the control board with a coil spring made of metal provided between the control board and the electrically connected component. In this respect, the coil spring is susceptible to deform under vibration in a direction perpendicular to a direction in which the coil spring expands and contracts. The direction in which the coil spring expands and contracts indicates the direction in which the control board and the electrically connected component are opposed to each other. If the coil spring is deformed in the direction perpendicular to the direction in which the coil spring expands and contracts, it results in a state where the coil becomes no longer in contact with at least one of the control board and the electrically connected component, and thus grounding of the control board is no longer available. To deal with this, in the existing brake hydraulic pressure control systems, a through hole is formed in a member disposed between the control board and the electrically connected component, and the coil spring is inserted into this through hole. Thereby, the coil spring is held by an inner wall of the through hole. Thus, even when the brake hydraulic pressure control system vibrates, it is possible to inhibit the coil spring from being deformed in the direction perpendicular to the direction in which the coil expands and contracts.

Accordingly, in the existing brake hydraulic pressure control systems which ground the control board using the coil spring, the through hole into which to insert the coil spring needs to be formed in the member disposed between the control board and the electrically connected component. Because this through hole needs to hold the coil spring with its inner wall, high positional accuracy and dimensional accuracy are required at the time of machining the through hole. For this reason, in the existing brake hydraulic pressure control systems which ground the control board using the coil spring, the manufacturing cost of a component having the member disposed between the control board and the electrically connected component inevitably increases, which results in an increase of the manufacturing cost of the brake hydraulic pressure control system.

On the other hand, the plate spring <NUM> is less susceptible to deform in the direction perpendicular to the direction in which the plate spring <NUM> expands and contracts as compared to the coil spring. Hence, in the brake hydraulic pressure control system <NUM> according to this embodiment, it is not necessary to insert the plate spring <NUM> into a through hole, formed in a member disposed between the control board <NUM> and the motor housing <NUM>, for the purpose of inhibiting the plate spring <NUM> from being deformed in the direction perpendicular to the direction in which the plate spring <NUM> expands and contracts. In other words, in the brake hydraulic pressure control system <NUM> according to this embodiment, it is not necessary to form the through hole in the member disposed between the control board <NUM> and the motor housing <NUM>. In addition, even when the brake hydraulic pressure control system <NUM> according to this embodiment has such a configuration that the plate spring <NUM> is inserted in to the through hole formed in the member disposed between the control board <NUM> and the motor housing <NUM>, it is not necessary to cause the through hole to hold the plate spring <NUM> with its inner wall. For this reason, even when the brake hydraulic pressure control system <NUM> according to this embodiment has such a configuration that the plate spring <NUM> is inserted in to the through hole formed in the member disposed between the control board <NUM> and the motor housing <NUM>, positional accuracy and dimensional accuracy at the time of machining the through hole may be lower than those of the existing through hole for holding the coil spring. To put it another way, in the brake hydraulic pressure control system <NUM> according to this embodiment, it is possible to reduce the manufacturing cost of the component having the member disposed between the control board <NUM> and the motor housing <NUM> as compared to the existing brake hydraulic pressure control systems which ground the control board using the coil spring. Accordingly, the brake hydraulic pressure control system <NUM> according to this embodiment makes it possible to suppress an increase of the manufacturing cost as compared to the existing brake hydraulic pressure control systems which ground the control board using the coil spring.

In addition, in this embodiment, as described above, the motor housing <NUM> is used as the electrically connected component. In order for the plate spring <NUM> and the electrically connected component to be electrically connected to each other stably, it is preferable to make flat a portion of the electrically connected component with which the end part <NUM> of the plate spring <NUM> is in contact. In the case of the motor housing <NUM>, since the portion with which the end part <NUM> of the plate spring <NUM> is in contact can be easily formed flat, the control board <NUM> can be grounded more stably.

Further, in this embodiment, the plate spring <NUM> includes, in its end part <NUM>, a planar part <NUM> which is in contact with the control board <NUM>. Due to the planar part <NUM>, the area of contact between the plate spring <NUM> and the control board <NUM> is increased, whereby the control board <NUM> can be grounded more stably. Moreover, in this embodiment, the plate spring <NUM> includes, in its end part <NUM>, a planar part <NUM> which is in contact with the motor housing <NUM>. Due to the planar part <NUM>, the area of contact between the plate spring <NUM> and the motor housing <NUM> is increased, whereby the control board <NUM> can be grounded more stably.

Note that, as seen in the width direction of the plate spring <NUM>, the plate spring <NUM> can have various shapes such as an arc shape. Note that, the width direction of the plate spring <NUM> indicates the width direction of a plate member for forming the plate spring <NUM>. The width direction of the plate spring <NUM> is a direction orthogonal to the paper surface of <FIG>, and is a lateral direction with respect to the paper surface of <FIG>. Here, the plate spring <NUM> according to this embodiment has the following shape. The plate spring <NUM> includes, at at least one position of a portion between the end part <NUM> and the end part <NUM>, a bend part <NUM> which bends in the thickness direction of the plate spring <NUM>. Note that, the thickness direction of the plate spring <NUM> indicates the thickness direction of the plate member for forming the plate spring <NUM>. To put it differently, when the plate spring <NUM> includes one bend part <NUM>, the plate spring <NUM> substantially has the shape of a V as seen in the width direction of the plate spring <NUM>. Meanwhile, when the plate spring <NUM> includes multiple bend parts <NUM>, the plate spring <NUM> has a zigzag shape as seen in the width direction of the plate spring <NUM>. By forming the plate spring <NUM> in such shapes, the plate spring <NUM> can be formed easily.

In addition, in this embodiment, the plate spring <NUM> includes a first plate spring <NUM> and a second plate spring <NUM>. Further, the bend part <NUM> of the first plate spring <NUM> and that of the second plate spring <NUM> bend in opposite directions from each other. When how the plate spring <NUM> is deformed in the direction perpendicular to the direction in which the plate spring <NUM> expands and contracts is observed at the time when the brake hydraulic pressure control system <NUM> vibrates, the plate spring <NUM> is more likely to deform in the direction perpendicular to the width direction of the plate spring <NUM> than in the width direction of the plate spring <NUM>. The direction perpendicular to the width direction of the plate spring <NUM> is a lateral direction with respect to the paper surface of <FIG>. Besides, when the brake hydraulic pressure control system <NUM> vibrates, the likelihood of deformation of the plate spring <NUM> in the left direction with respect to the paper surface of <FIG> and the likelihood of deformation of the plate spring <NUM> in the right direction with respect to the paper surface of <FIG> vary depending on the direction of bend of the bend part <NUM>. Thus, in this embodiment, the bend part <NUM> of the first plate spring <NUM> and that of the second plate spring <NUM> bend in opposite directions from each other. By forming the first plate spring <NUM> and the second plate spring <NUM> in this manner, in the lateral direction with respect to the paper surface of <FIG>, these plate springs are likely to bend in opposite directions from each other. As a result, by forming the first plate spring <NUM> and the second plate spring <NUM> in this manner, the first plate spring <NUM> and the second plate spring <NUM> as a whole become less likely to deform in both directions in the lateral direction with respect to the paper surface of <FIG>. Accordingly, by forming the first plate spring <NUM> and the second plate spring <NUM> in this manner, the control board <NUM> can be grounded more stably. Note that, in this embodiment, the planar part <NUM> of the first plate spring <NUM> and the planar part <NUM> of the second plate spring <NUM> are formed in one unit, and the planar part <NUM> of the first plate spring <NUM> and the planar part <NUM> of the second plate spring <NUM> are formed in one unit.

Here, in this embodiment, the state where the bend part <NUM> of the first plate spring <NUM> and that of the second plate spring <NUM> bend in opposite directions from each other does not mean that the bend part <NUM> of the first plate spring <NUM> and that of the second plate spring <NUM> bend in exactly opposite directions from each other. Specifically, the second plate spring <NUM> in this embodiment takes such a posture that the first plate spring <NUM> is rotated by <NUM> degrees while a virtual line, extending in the direction in which the control board <NUM> and the motor housing <NUM> are opposed to each other, is used as the reference of rotation. While not limited thereto, the second plate spring <NUM> may take such a posture that the first plate spring <NUM> is rotated by less than <NUM> degrees while the virtual line, extending in the direction in which the control board <NUM> and the motor housing <NUM> are opposed to each other, is used as the reference of rotation. In this respect, the second plate spring <NUM> may take any posture as long as it takes such a posture that the first plate spring <NUM> is rotated by more than <NUM> degrees while the virtual line, extending in the direction in which the control board <NUM> and the motor housing <NUM> are opposed to each other, is used as the reference of rotation. Even when the second plate spring <NUM> takes the above posture, in this embodiment, such a posture is also referred to as the state where the bend part <NUM> of the first plate spring <NUM> and that of the second plate spring <NUM> bend in opposite directions from each other.

In addition, as illustrated in <FIG>, when the first plate spring <NUM> and the second plate spring <NUM> are observed in the direction perpendicular to the width direction of the first plate spring <NUM>, in this embodiment, the first plate spring <NUM> and the second plate spring <NUM> are arranged so as not to overlap with each other. While not limited thereto, when the first plate spring <NUM> and the second plate spring <NUM> are observed in the direction perpendicular to the width direction of the first plate spring <NUM>, the first plate spring <NUM> and the second plate spring <NUM> may overlap with each other. Besides, as illustrated in <FIG>, when the first plate spring <NUM> and the second plate spring <NUM> are observed in the width direction of the first plate spring <NUM>, in this embodiment, the first plate spring <NUM> and the second plate spring <NUM> are arranged so as to overlap with each other. While not limited thereto, when the first plate spring <NUM> and the second plate spring <NUM> are observed in the width direction of the first plate spring <NUM>, the first plate spring <NUM> and the second plate spring <NUM> do not necessarily have to overlap with each other.

Here, the brake hydraulic pressure control system <NUM> according to this embodiment is mounted to the straddle-type vehicle <NUM> while the plate spring <NUM> takes a posture as illustrated in <FIG>. Specifically, when the brake hydraulic pressure control system <NUM> is mounted to the straddle-type vehicle <NUM>, the plate spring <NUM> takes such a posture that the width direction of the plate spring <NUM> does not extend horizontally. More specifically, in this embodiment, when the brake hydraulic pressure control system <NUM> is mounted to the straddle-type vehicle <NUM>, the plate spring <NUM> takes such a posture that the width direction of the plate spring <NUM> extends in a vertical direction.

The straddle-type vehicle <NUM> is likely to vibrate in the vertical direction during traveling. Meanwhile, as described previously, the plate spring <NUM> in which the bend part <NUM> is formed is likely to deform in the direction perpendicular to the width direction of the plate spring <NUM>. For this reason, by setting the brake hydraulic pressure control system <NUM> in such a posture that the width direction of the plate spring <NUM> does not extend horizontally when the system is mounted to the straddle-type vehicle <NUM>, the direction in which the plate spring <NUM> is likely to deform becomes different from the vertical direction in which the straddle-type vehicle <NUM> is likely to vibrate greatly during traveling. Accordingly, by setting the brake hydraulic pressure control system <NUM> in such a posture that the width direction of the plate spring <NUM> does not extend horizontally when the system is mounted to the straddle-type vehicle <NUM>, it is possible to further inhibit the plate spring <NUM> from becoming not in contact with the motor housing <NUM>, whereby the control board <NUM> can be grounded more stably.

The effect of the brake hydraulic pressure control system <NUM> according to this embodiment is described.

The brake hydraulic pressure control system <NUM> according to this embodiment includes: the substrate <NUM> in which the sub-flow channel <NUM> for brake fluid is formed; the motor <NUM> which is a driving source for the pump device <NUM> provided in the sub-flow channel <NUM>; the control board <NUM> for the motor <NUM>; and the housing <NUM> connected to the substrate <NUM>. The motor <NUM> includes; the stator <NUM>; the rotor <NUM>; and the output shaft <NUM> secured to the rotor <NUM>. The control board <NUM> is housed in the housing <NUM>. The motor <NUM> is a brushless motor, and is disposed in the space surrounded by the substrate <NUM> and the housing <NUM>. The output shaft <NUM> is secured to the rotor <NUM> in such a way that both the end part 45a which is a first end part and the end part 45b which is a second end part of the output shaft <NUM> protrude from the rotor <NUM>. The motor <NUM> also includes: the bearing <NUM> which is a first bearing; the bearing <NUM> which is a second bearing; and the motor housing <NUM>. The bearing <NUM> is configured to rotatably support the output shaft <NUM> at a position between the end part 45a and the rotor <NUM>. The bearing <NUM> is configured to rotatably support the output shaft <NUM> at a position between the end part 45b and the rotor <NUM>. The stator <NUM> and the rotor <NUM> are housed in the motor housing <NUM>. In addition, the motor housing <NUM> holds the bearing <NUM> and the bearing <NUM>. The brake hydraulic pressure control system <NUM> further includes the detection mechanism <NUM> which is configured to detect the rotation state of the output shaft <NUM>. In addition, the concave part <NUM> which is a first concave part open toward the housing <NUM> is formed in the substrate <NUM>, and the bearing <NUM> of the motor <NUM> is inserted into the concave part <NUM>.

In the brake hydraulic pressure control system <NUM> having the above configuration, since the motor <NUM> is disposed in the space surrounded by the substrate <NUM> and the housing <NUM>, it is possible to reduce the size of the brake hydraulic pressure control system <NUM> as compared to the existing brake hydraulic pressure control systems. In addition, the brake hydraulic pressure control system <NUM> having the above configuration positions the motor <NUM> by inserting the bearing <NUM>, originally included in the motor <NUM>, into the concave part <NUM>. Accordingly, in the brake hydraulic pressure control system <NUM> having the above configuration, it is possible to improve the positional accuracy of the motor <NUM> even in the case of installing the motor <NUM> in the space surrounded by the substrate <NUM> and the housing <NUM>.

It is preferable that the pump device <NUM> includes the piston 31a which is configured to perform a translatory reciprocating movement. In addition, the eccentric body <NUM> which is configured to bear the end part of the piston 31a is attached to the output shaft <NUM> in the region between the portion of the output shaft supported by the bearing <NUM> and the end part 45a. Besides, the region of the output shaft <NUM> between the portion where the eccentric body <NUM> is attached and the end part 45a is free. With such a configuration, it is not necessary to prepare, in the substrate <NUM>, a space for installing a bearing which is configured to support the output shaft <NUM> so that it is rotatable in this region, whereby the brake hydraulic pressure control system <NUM> can be further reduced in size.

It is preferable that the bearing <NUM> is fitted into the concave part <NUM>. With such a configuration, it is possible to further improve the positional accuracy of the motor <NUM>. In addition, it is preferable that the bearing <NUM> is loosely fitted into the concave part <NUM> with a clearance therebetween. With such a configuration, it is possible to fit the bearing <NUM> into the concave part <NUM> easily, and thus reduce the number of man-hours for assembling the brake hydraulic pressure control system <NUM>.

It is preferable that the motor housing <NUM> includes the flange <NUM> which protrudes outward. The concave part <NUM> which is a second concave part open toward the housing <NUM> and into which the flange <NUM> is inserted is formed in the substrate <NUM>. The motor <NUM> is secured to the substrate <NUM> in such a way that the flange <NUM> is pinched between the plastic deformation part <NUM>, formed in the inner circumferential surface of the concave part <NUM>, and the bottom part <NUM> of the concave part <NUM>. With such a configuration, it is not necessary to prepare bolts for securing the motor <NUM>, and also not necessary to form female screw parts, into which the bolts are screwed, in the substrate <NUM>. Accordingly, the brake hydraulic pressure control system <NUM> can be further reduced in size.

It is preferable that the detection mechanism <NUM> includes: the rotation element <NUM> which is configured to rotate together with the output shaft <NUM>; and the sensor <NUM> which is configured to detect the rotation position of the rotation element <NUM>. The rotation element <NUM> is located between the output shaft <NUM> and the control board <NUM>, and the sensor <NUM> is mounted to the control board <NUM>. Such a configuration makes it unnecessary to provide an additional control board other than the control board <NUM> for mounting the sensor <NUM> thereto, whereby the brake hydraulic pressure control system <NUM> can be further reduced in size.

Claim 1:
A brake hydraulic pressure control system (<NUM>) for a straddle-type vehicle (<NUM>) comprising:
a substrate (<NUM>) in which a flow channel (<NUM>) for brake fluid is formed;
a motor (<NUM>) which includes a stator (<NUM>), a rotor (<NUM>), and an output shaft (<NUM>) secured to the rotor (<NUM>), and is a driving source for a pump device (<NUM>) provided in the flow channel (<NUM>);
a control board (<NUM>) of the motor (<NUM>); and
a housing (<NUM>) which houses therein the control board (<NUM>), and is connected to the substrate (<NUM>), wherein
the motor (<NUM>) is a brushless motor, and is disposed in a space surrounded by the substrate (<NUM>) and the housing (<NUM>),
the output shaft (<NUM>) is secured to the rotor (<NUM>) in such a way that both a first end part (45a) and a second end part (45b) of the output shaft (<NUM>) protrude from the rotor (<NUM>),
the motor (<NUM>) includes
a first bearing (<NUM>) which is configured to rotatably support the output shaft (<NUM>) at a position between the first end part (45a) and the rotor (<NUM>),
a second bearing (<NUM>) which is configured to rotatably support the output shaft (<NUM>) at a position between the second end part (45b) and the rotor (<NUM>), and
a motor housing (<NUM>) which houses therein the stator (<NUM>) and the rotor (<NUM>), and holds the first bearing (<NUM>) and the second bearing (<NUM>),
the brake hydraulic pressure control system (<NUM>) further includes a detection mechanism (<NUM>) which is configured to detect a rotation state of the output shaft (<NUM>),
a first concave part (<NUM>) which opens toward the housing (<NUM>) is formed in the substrate (<NUM>), and
the first bearing (<NUM>) of the motor (<NUM>) is inserted into the first concave part (<NUM>),
wherein the pump device (<NUM>) includes a piston (31a) which is configured to perform a translatory reciprocating movement
characterized in that
an eccentric body (<NUM>) which is configured to bear an end part of the piston (31a) is attached to the output shaft (<NUM>) in a region between a portion of the output shaft supported by the first bearing (<NUM>) and the first end part (45a), and
a region of the output shaft (<NUM>) between the portion where the eccentric body (<NUM>) is attached and the first end part (45a) is free.