Hydraulic control unit and saddle-type vehicle

Abstract

According to the present invention, there is obtained a hydraulic control unit for a saddle-type vehicle, wherein said hydraulic control unit can be made more compact than before. A hydraulic control unit according to the present invention comprises an accumulator that stores a brake fluid flowing in from a wheel cylinder. The accumulator comprises: a cylinder chamber; a piston which is provided so as to be able to reciprocate in the cylinder chamber and which partitions the interior of the cylinder chamber into a reservoir part for storing the brake fluid and a spring accommodating part; and a spring which is accommodated in the spring accommodating part and which presses the piston toward the reservoir part. The piston comprises a protruding part that protrudes into the spring accommodating part and is inserted into the inner-circumferential side of the spring, and when the piston moves in a direction such that the reservoir part expands, a leading-end portion of the protruding part abuts an end portion of the cylinder chamber on the spring accommodating part side, thus acting as a stopper.

Description

[0001] [Document name] Statement

[0002] [Title of invention] Hydraulic pressure control unit and saddle-type vehicle

[0003] [Technical Field]

[0004]

[001] The present invention relates to a hydraulic control unit for a saddle-ride type vehicle, and to a saddle-ride type vehicle equipped with the hydraulic control unit.

[0005] [Background technology]

[0006] [. 0 0 2] Some conventional vehicles are equipped with a hydraulic control unit that controls the pressure of brake fluid in a hydraulic circuit. For example, when the driver of the vehicle operates a brake operating device such as a brake lever, the hydraulic control unit increases or decreases the pressure of the brake fluid in the hydraulic circuit to adjust the braking force generated on the wheels and perform anti-lock brake control. Such a hydraulic control unit is equipped with an accumulator that stores brake fluid released from the wheel cylinder. Furthermore, the accumulator in a conventional hydraulic control unit is configured as follows:

[0007]

[003] The accumulator of a conventional hydraulic control unit includes a cylinder chamber, a piston, and a spring. The piston is reciprocally movable within the cylinder chamber. The piston divides the interior of the cylinder chamber into a fluid reservoir that stores brake fluid released from the wheel cylinder, and a spring accommodating chamber that accommodates a spring. The spring housed in the spring accommodating chamber presses the piston toward the fluid reservoir. The pressing force of the spring forces the brake fluid stored in the fluid reservoir out of the fluid reservoir and back into the master cylinder. In the accumulator of a conventional hydraulic control unit, the piston has a recess at the end on the spring accommodating chamber side into which the spring is inserted. In other words, the piston-side end of the spring is inserted into a recess in the piston, and the outer periphery is supported by the piston (see, for example, Patent Document 1).

[0008] [Prior art documents]

[0009] [Patent documents]

[0010]

. 0 0 4

[0011] [Patent Document 1] Patent No. 7013488

[0012] Summary of the Invention

[0013] [Problem to be solved by the invention]

[0014]

[005] Compared to vehicles such as four-wheeled automobiles, straddle-type vehicles have limited installation space for hydraulic control units, so there is a demand for miniaturization of hydraulic control units installed in straddle-type vehicles. To miniaturize a hydraulic control unit, the accumulator that constitutes the hydraulic control unit must also be miniaturized. On the other hand, with regard to the spring inside the accumulator, if an attempt is made to suppress a decrease in the spring's pressing force, the spring may need to be made larger. This may result in an increase in the outer diameter of the piston and therefore in a larger cylinder chamber, making it difficult to miniaturize the accumulator. As such, conventional hydraulic control units for straddle-type vehicles have had the problem that it is difficult to miniaturize the accumulator, and therefore the hydraulic control unit itself.

[0015] The present invention has been made in light of the above-mentioned problems, and has as its first object to provide a hydraulic control unit that can be made smaller than conventional units. Also, as a second object of the present invention, it is possible to provide a saddle-ride type vehicle equipped with such a hydraulic control unit.

[0016] [Means for solving the problem]

[0017]

[007] A hydraulic control unit according to the present invention is a hydraulic control unit for a brake system mounted on a saddle-ride type vehicle and capable of performing antilock brake control, and comprises: a main flow path that communicates a master cylinder with a wheel cylinder; an inlet valve that is provided in the main flow path and opens and closes the main flow path; a secondary flow path having one end connected to an area of ​​the main flow path that is on the wheel cylinder side with respect to the inlet valve; a release valve that is provided in the secondary flow path and opens and closes the secondary flow path; an accumulator that is connected to the other end of the secondary flow path and stores brake fluid that has flowed from the wheel cylinder into the secondary flow path, and the accumulator comprises: a cylinder chamber connected to the other end of the secondary flow path; and a spring that is accommodated in the spring accommodating portion and presses the piston toward the fluid reservoir, forcing the brake fluid stored in the fluid reservoir out of the fluid reservoir. The piston has a protrusion that protrudes into the spring accommodating portion and is inserted into the inner periphery of the spring, and when the piston moves in the direction in which the fluid reservoir expands, its tip abuts against the spring accommodating portion side end of the cylinder chamber, which is the end of the spring accommodating portion side, to serve as a stopper.

[0018]

[0008] The saddle-type vehicle according to the present invention is equipped with the hydraulic control unit according to the present invention.

[0019] [Effects of the Invention]

[0020]

[0009] The present invention provides a hydraulic control unit that can be made smaller than conventional units. The present invention also provides a saddle-type vehicle equipped with such a hydraulic control unit.

[0021] BRIEF DESCRIPTION OF THE DRAWINGS

[0022] [ 0 0 1 0 ]

[0023] FIG. 1 is a diagram showing the schematic configuration of a saddle-type vehicle equipped with a brake system equipped with a hydraulic pressure control unit according to an embodiment of the present invention.

[0024] [Figure 2] A diagram showing the general configuration of a brake system equipped with a hydraulic control unit according to an embodiment of the present invention.

[0025] [Figure 3] A side view showing, in partial cross section, the base portion of the hydraulic control unit according to the present invention.

[0026] [Figure 4] A side view showing, in partial cross section, the base portion of the hydraulic control unit according to the present invention.

[0027] [Figure 5] A side view showing, in partial cross section, the base portion of a modified example of the hydraulic control unit according to the present invention.

[0028] [Figure 6] A diagram showing the schematic configuration of a brake system equipped with a modified example of a hydraulic control unit according to an embodiment of the present invention.

[0029] [Figure 7] A side view showing, in partial cross section, the base portion of the hydraulic control unit provided in the brake system shown in Figure 6.

[0030] [Mode for Carrying Out the Invention]

[0031]

[0011] Below, an example of a hydraulic control unit and a saddle-ride type vehicle according to the present invention will be described with reference to the drawings.

[0032]

[0012] Note that, although the following description will be given of the present invention as applied to a bicycle (e.g., two-wheeled vehicle, three-wheeled vehicle, etc.), which is an example of a straddle-type vehicle, the present invention may also be applied to other straddle-type vehicles other than bicycles. Examples of other straddle-type vehicles other than bicycles include motorcycles, three-wheeled vehicles, and buggies that use at least one of an engine and an electric motor as a drive source. Furthermore, the term "bicycle" refers to any vehicle that can be propelled along a road by applying pedal force to the pedals. In other words, bicycles include standard bicycles, electrically assisted bicycles, and electric bicycles. Furthermore, motorcycles and three-wheeled vehicles refer to so-called motorcycles, and motorcycles include motorcycles, scooters, electric scooters, etc.

[0033]

[0013] Furthermore, the configurations, operations, etc. described below are merely examples, and the hydraulic control unit and saddle-ride type vehicle according to the present invention are not limited to such configurations, operations, etc. For example, although the following describes a case in which the hydraulic control unit has one hydraulic circuit system, the number of hydraulic circuits in the hydraulic control unit is not limited to one system. The hydraulic control unit may have two or more hydraulic circuits system.

[0034]

[0014] In addition, in each drawing, the same or similar members or parts are given the same reference numerals, or the reference numerals are omitted. In addition, illustrations of detailed structures are simplified or omitted as appropriate. In addition, duplicated explanations are simplified or omitted as appropriate.

[0035]

[0015] Embodiment <Installation of brake system with hydraulic pressure control unit on straddle-type vehicle> Installation of a brake system with a hydraulic pressure control unit according to this embodiment on a straddle-type vehicle will be described. Fig. 1 is a diagram showing the schematic configuration of a straddle-type vehicle on which a brake system with a hydraulic pressure control unit according to an embodiment of the present invention is installed.

[0036]

[0016] A saddle-type vehicle 200, for example a bicycle, includes a frame 210, a turning unit 230, a saddle 218, pedals 219, a rear wheel 220, and a rear wheel braking unit 260.

[0037]

[0017] The frame 210 includes, for example, a head tube 211 that pivotally supports the steering column 231 of the turning unit 230, a top tube 212 and a down tube 213 that are connected to the head tube 211, a seat tube 214 that is connected to the top tube 212 and the down tube 213 and holds a saddle 218, and stays 215 that are connected to the upper and lower ends of the seat tube 214 and hold a rear wheel 220 and a rear wheel braking unit 260.

[0038]

[0018] The turning unit 230 includes a steering column 231, a handle stem 232 held by the steering column 231, a handlebar 233 held by the handle stem 232, a brake operating unit 240 attached to the handlebar 233, a front fork 216 connected to the steering column 231, a front wheel 217 rotatably held by the front fork 216, and a front wheel braking unit 250. The front forks 216 are provided on both sides of the front wheel 217. One end of the front fork 216 is connected to the steering column 231, and the other end is connected to the center of rotation of the front wheel 217.

[0039]

[0019] The brake operating unit 240 includes a mechanism used as an operating unit for the front wheel braking unit 250 and a mechanism used as an operating unit for the rear wheel braking unit 260. For example, the mechanism used as an operating unit for the front wheel braking unit 250 is disposed on the right end side of the handlebar 233, and the mechanism used as an operating unit for the rear wheel braking unit 260 is disposed on the left end side of the handlebar 233.

[0040] The saddle-type vehicle 200 configured as described above includes a hydraulic pressure control unit 1. In this embodiment, the hydraulic pressure control unit 1 is attached to the front fork 216 of the turning section 230. The hydraulic pressure control unit 1 may be attached to a structure other than the front fork 216. The hydraulic pressure control unit 1 is a unit that controls the pressure of the brake fluid in the front wheel braking section 250. The rear wheel braking section 260 may be a braking section that generates braking force by increasing the pressure of the brake fluid, or may be a braking section that generates braking force mechanically (for example, a braking section that generates braking force by generating tension in a wire).

[0041]

[0021] The saddle-riding type vehicle 200 also includes a power supply unit 270 that serves as the power source for the hydraulic control unit 1. The power supply unit 270 is attached, for example, to the down tube 213 of the frame 210. The power supply unit 270 may be a battery or a generator. Examples of generators include those that generate electricity when the saddle-riding type vehicle 200 is traveling (for example, a hub dynamo that generates electricity through the rotation of the front wheel 217 or the rear wheel 220, or an electric motor that is the drive source for the front wheel 217 or the rear wheel 220 and generates regenerative power), and those that generate electricity using sunlight.

[0042]

[0022] In other words, the saddle-riding type vehicle 200 is equipped with a brake system 100 including at least a brake operating unit 240, a front wheel brake unit 250, a hydraulic pressure control unit 1, and a power supply unit 270. The brake system 100 can perform, for example, anti-lock brake control by controlling the pressure of the brake fluid in the front wheel brake unit 250 using the hydraulic pressure control unit 1.

[0043] [ 0 0 2 3 ]

[0044] <Configuration of Brake System> The configuration of a brake system equipped with a hydraulic control unit according to this embodiment will be described. Fig. 2 is a diagram showing the schematic configuration of a brake system according to this embodiment. The hydraulic control unit 1 has a base body 10. A master cylinder port 11 and a wheel cylinder port 12 are formed in the base body 10. The hydraulic control unit 1 also has an accumulator 30. The accumulator 30 is provided in the base body 10 and stores brake fluid released from a wheel cylinder 251 (described below) during anti-lock brake control.

[0045]

[0024] The base 10 also has a main flow path 13, a sub-flow path 14, and a return flow path 15 as flow paths for brake fluid. The main flow path 13 is a flow path that connects the master cylinder port 11 and the wheel cylinder port 12. One end 14a of the sub-flow path 14 is connected to an intermediate portion 13a of the main flow path 13. The other end 14b of the sub-flow path 14 is connected to an accumulator 30. That is, the accumulator 30 stores brake fluid that flows into the sub-flow path 14 from a wheel cylinder 251 (described later). The return flow path 15 connects the accumulator 30 to the master cylinder port 11. In this embodiment, one end 15a of the return flow path 15 is connected to the accumulator 30. The other end 15b of the return flow path 15 is connected to an intermediate portion 13b of the main flow path 13.

[0046]

[0025] A brake operating unit 240 is connected to the master cylinder port 11 via a fluid pipe 101. The brake operating unit 240 includes a brake lever 241, a master cylinder 242, and a reservoir 243. Of the components of the brake operating unit 240, the master cylinder 242 is connected to the fluid pipe 101. That is, the fluid pipe 101 communicating with the master cylinder 242 is connected to the master cylinder port 11. The master cylinder 242 also includes a piston (not shown) that moves in conjunction with the driver's operation of the brake lever 241, and is connected to a main flow path 13 via the fluid pipe 101 and the master cylinder port 11. Piston movement The return flow path 15 is a flow path that communicates between the master cylinder 242 and a fluid reservoir 41 (described later) of the accumulator 30. The rotor 252 is held by the front wheel 217 and rotates together with the front wheel 217. As the piston of the wheel cylinder 251 moves, brake pads (not shown) are pressed against the rotor 252, braking the front wheel 217.

[0047]

[0027] The hydraulic control unit 1 also includes an inlet valve 21 and a release valve 22 provided on the base 10. The inlet valve 21 is provided in the main flow path 13. Specifically, the inlet valve 21 is provided in the region of the main flow path 13 between the intermediate portions 13a and 13b. That is, the end portion 14a of the secondary flow path 14 is connected to the region of the main flow path 13 on the wheel cylinder 251 side with respect to the inlet valve 21. The opening and closing operation of the inlet valve 21 opens and closes the portion of the main flow path 13 where the inlet valve 21 is provided, thereby controlling the flow rate of brake fluid flowing through this region. The release valve 22 is provided in the secondary flow path 14. The opening and closing operation of the release valve 22 opens and closes the flow path portion of the sub-flow path 14 where the release valve 22 is installed, thereby controlling the flow rate of the brake fluid flowing through this area.The opening and closing operation of the inlet valve 21 and the release valve 22 controls the pressure of the brake fluid.

[0048]

[0028] For example, when the inlet valve 21 is de-energized, it allows the flow of brake fluid in both directions. When the inlet valve 21 is energized, it is closed and blocks the flow of brake fluid. That is, in this embodiment, the inlet valve 21 is a solenoid valve that is open when de-energized. Also, for example, when the release valve 22 is de-energized, it blocks the flow of brake fluid. When the release valve 22 is energized, it is open and allows the flow of brake fluid in the direction toward the accumulator 30. That is, in this embodiment, the release valve 22 is a solenoid valve that is closed when de-energized.

[0049]

[0029] The hydraulic control unit 1 also includes a hydraulic pressure detection sensor 103 for detecting the pressure of the brake fluid in the wheel cylinder 251. In this embodiment, the hydraulic pressure detection sensor 103 is provided in an area of ​​the main flow path 13 on the wheel cylinder 251 side relative to the inlet valve 21.

[0050]

[0030] The hydraulic control unit 1 also includes a control device 80. Signals from various sensors, such as hydraulic pressure detection sensors 103 and wheel speed sensors (not shown) for detecting the rotational speed of the front wheels 217, are input to the control device 80. The various components of the control device 80 may be arranged together or may be distributed. The control device 80 may include, for example, a microcomputer, a microprocessor unit, or the like, or may include updatable firmware, or may include a program module executed by commands from a CPU, or the like.

[0051]

[0031] The control device 80 controls the supply of electricity to the inlet valve 21 and the release valve 22. In other words, the control device 80 controls the opening and closing operations of the inlet valve 21 and the release valve 22, thereby controlling the pressure of the brake fluid in the wheel cylinder 251, i.e., the braking force of the front wheel 217.

[0052]

[0032] For example, when the front wheels 217 are being braked by the driver operating the brake lever 241, if the control device 8〇 determines from the signal of the wheel speed sensor (not shown) that the front wheels 217 are locked or there is a possibility of locking, it starts anti-lock brake control.

[0053]

[0033] When anti-lock brake control is initiated, the control device 80 closes the inlet valve 21 and blocks the flow of brake fluid from the master cylinder 242 to the wheel cylinder 251, thereby suppressing an increase in the brake fluid pressure in the wheel cylinder 251. Meanwhile, the control device 80 opens the release valve 22 and allows the flow of brake fluid from the wheel cylinder 251 to the accumulator 30, thereby reducing the pressure of the brake fluid in the wheel cylinder 251. This releases or prevents the front wheels 217 from locking. When the control device 80 determines from the signal of the hydraulic pressure detection sensor 103 that the brake fluid in the wheel cylinder 251 has been reduced to a predetermined value, it closes the release valve 22 and opens the inlet valve 21 for a short period of time to increase the pressure of the brake fluid in the wheel cylinder 251. The control device 80 may increase or decrease the pressure of the wheel cylinder 251 only once, or may repeat this process multiple times.

[0054]

[0034] When anti-lock brake control ends, the control device 80 opens the inlet valve 21 and closes the release valve 22. When the anti-lock brake control ends and the brake lever 241 is returned, the pressure of the brake fluid in the master cylinder 242 decreases and approaches atmospheric pressure. When the brake fluid pressure in the master cylinder 242 falls below a specified pressure, the brake fluid in the wheel cylinder 251 passes through the inlet valve 21 and is returned to the master cylinder 242. The brake fluid in the accumulator 30 is discharged outside the accumulator 30 without boosting (i.e., without a pump), flows into the return flow path 15, and returns to the master cylinder 242.

[0055]

[0035] <Configuration of hydraulic control unit> Figures 3 and 4 are side views, partly in cross section, showing the base portion of the hydraulic control unit according to the present invention. Fig. 3 shows a state in which the piston 50 of the accumulator 30 has moved to the end of its movement on the liquid reservoir 41 side. Fig. 4 shows a state in which the piston 50 of the accumulator 30 has moved to the end of its movement on the spring accommodating section 42 side.

[0056]

[0036] As described above, the hydraulic control unit 1 includes a base 10 and an accumulator 30 provided on the base 10. The base 10 is a metal component made of, for example, an aluminum alloy. The base 10 is, for example, a substantially rectangular parallelepiped. Each side surface of the base 10 may be flat, may include a curved portion, or may include a step.

[0057]

[0037] The accumulator 30 includes a cylinder chamber 40, a piston 50, and a spring 31. In this embodiment, the cylinder chamber 40 is configured as follows: The base 10 includes, for example, a cylindrical accumulator recess 16 that opens on one side surface. The opening of this accumulator recess 16 is closed with a lid 18 to form the cylinder chamber 40. An end 14b of a sub-flow path 14 and an end 15a of a return flow path 15 are connected to the cylinder chamber 40. In this embodiment, the bottom of the accumulator recess 16 is the reservoir side end 43 against which the piston 50 abuts when it moves to the end of its movement on the reservoir 41 side. Also, the lid 18 is the spring accommodating side end 44 against which the piston abuts when it moves to the end of its movement on the spring accommodating portion 42 side.

[0058]

[0038] The piston 50 has, for example, a generally cylindrical shape. The piston 50 is provided in the cylinder chamber 40 so as to be able to reciprocate freely. The piston 50 also divides the interior of the cylinder chamber 40 into a fluid reservoir 41 and a spring accommodating portion 42. An end 14b of the secondary flow path 14 and an end 15a of the return flow path 15 are connected to the fluid reservoir 41 in the cylinder chamber 40. That is, the fluid reservoir 41 is a portion of the accumulator 30 that collects brake fluid that has flowed from the wheel cylinder 251 into the secondary flow path 14. The spring 31 is accommodated in the spring accommodating portion 42 in the cylinder chamber 40. The spring 31 presses the piston 50 toward the reservoir 41, forcing the brake fluid stored in the reservoir 41 out of the reservoir 41.

[0059]

[0039] In the accumulator 30 configured in this manner, during antilock brake control, the brake fluid flowing from the wheel cylinder 251 to the accumulator 30 flows into the fluid reservoir 41. As a result, the piston 50 is pressed by the brake fluid and moves in the direction that expands the fluid reservoir 41. Furthermore, the piston 50 moving in the direction that expands the fluid reservoir 41 stops when it abuts the spring accommodating portion side end 44. This state is the state in which the piston 50 has moved to the moving end on the spring accommodating portion 42 side. When anti-lock brake control ends and the force of spring 31 pressing against the piston becomes greater than the force of the brake fluid in reservoir 41 pressing against the piston, the difference in force causes piston 50 to move in the direction that reservoir 41 contracts. As a result, the brake fluid in reservoir 41 is pushed out into return flow path 15 and returns to master cylinder 242. Then, when piston 50, moving in the direction that reservoir 41 contracts, comes to abut reservoir side end 43 and stops, the brake fluid in reservoir 41 is no longer pushed out into return flow path 15. This is the state in which piston 50 has moved to the end of its movement on the reservoir 41 side.

[0060]

[0040] Here, compared to vehicles such as four-wheeled automobiles, straddle-type vehicles have limited installation space for hydraulic control units, so there is a demand for miniaturization of hydraulic control units installed in straddle-type vehicles. To miniaturize the hydraulic control unit, the accumulator, which is a component of the hydraulic control unit, must also be miniaturized. On the other hand, with regard to the spring inside the accumulator, suppressing a decrease in the spring's pressing force can lead to an increase in the size of the spring. This can lead to an increase in the outer diameter of the piston and, therefore, a larger cylinder chamber, making it difficult to miniaturize the accumulator. Thus, conventional hydraulic control units for straddle-type vehicles have had the problem that it is difficult to miniaturize the accumulator and therefore the hydraulic control unit itself.

[0061]

[0041] Specifically, in a conventional accumulator, the piston-side end of the spring is supported by the piston. In this case, in a conventional hydraulic control unit for a saddle-ride type vehicle, the piston-side end of the spring is supported by the piston as follows: The piston of a conventional hydraulic control unit for a saddle-ride type vehicle has a recess into which the spring is inserted at the end on the spring accommodating chamber side. That is, the piston-side end of the spring is inserted into the recess of the piston, and the outer periphery is supported by the piston. In addition, in a conventional hydraulic control unit for a saddle-ride type vehicle, the tip of the recess of the piston abuts against the end of the cylinder chamber when the piston moves in the direction in which the liquid reservoir expands, and also functions as a stopper. If the components of a conventional accumulator configured in this way were to be miniaturized without changing their shape, the thickness of the side wall of the recessed portion of the piston, which functions as a stopper, could not be made too thin, so the spring would be small and the spring's pressing force would be insufficient. If the spring diameter, natural length, etc. were increased to ensure the spring's pressing force, the outer diameter of the piston would also increase, which would increase the cylinder chamber, making it difficult to miniaturize the accumulator. As such, in conventional hydraulic control units for saddle-ride type vehicles, it was difficult to miniaturize the accumulator, and therefore the hydraulic control unit itself.

[0062]

[0042] On the other hand, in the hydraulic control unit 1 according to this embodiment, the piston 50 has a protrusion 51 that protrudes into the spring accommodating portion 42 and is inserted into the inner peripheral side of the spring 31. When the piston 50 moves in the direction in which the liquid reservoir 41 expands, the tip end 52 of the protrusion 51 abuts against the spring accommodating portion side end 44, which is the end of the cylinder chamber 40 on the spring accommodating portion 42 side, to serve as a stopper. In other words, the piston 50 of the hydraulic control unit 1 according to this embodiment is configured to support the inner peripheral side of the spring 31 by the protrusion 51 inserted into the inner peripheral side of the spring 31. For this reason, the accumulator 30 of the hydraulic control unit 1 according to this embodiment can use a spring 31 that is larger than conventional ones, even if the outer diameter of the piston 50 is the same as the outer diameter of a conventional piston (or even if it is smaller than the outer diameter of a conventional piston). In other words, even if a spring 31 larger than conventional ones is used to ensure the pressing force of the spring 31, it is possible to prevent the outer diameter of the piston 50 from becoming too large, making it easy to reduce the size of the cylinder chamber 40. Therefore, the hydraulic control unit 1 according to this embodiment can reduce the size of the accumulator 30 without making the spring 31 smaller than conventional ones. For this reason, the hydraulic control unit 1 according to this embodiment can be made smaller than conventional hydraulic control units for saddle-ride type vehicles.

[0063]

[0043] Here, it is preferable that the hydraulic control unit 1 according to this embodiment has the following configuration.

[0064] 3 and 4, the hydraulic control unit 1 according to this embodiment includes an inner peripheral surface 45 of the cylinder chamber 4 extending along the reciprocating direction of the piston 50 (left-right direction on the paper in FIGS. 3 and 4), and an outer peripheral surface 53 of the piston 50 extending along the reciprocating direction of the piston 50, and a ring 32 that seals between them. The piston 50 also includes a groove 54 on the outer peripheral surface 53 that accommodates the ring 32. When the piston 50 of the hydraulic control unit 1 has a groove portion 54 in this manner, preferably, in a direction perpendicular to the reciprocating direction of the piston 50 (the vertical direction on the paper in Figures 3 and 4), the distance L1 between the inner surface 45 of the cylinder chamber 40 and the bottom 55 of the groove portion 54 is shorter than the distance L2 between the convex portion 51 of the piston 50 and the inner surface 45 of the cylinder chamber 40.

[0065]

[0045] As shown in Fig. 4, when the piston 50 has moved to the end of its travel on the spring accommodating portion 42 side, the force pressing the piston 50 by the brake fluid in the fluid reservoir 41 is supported by the convex portion 51. Therefore, when the piston 50 has moved to the end of its travel on the spring accommodating portion 42 side, shear stress is generated in the piston 50 at the position shown by the two-dot chain line in Fig. 4. For this reason, the length of the piston 50 on the two-dot chain line needs to be long enough to ensure rigidity that can withstand the shear stress. In this case, when two pistons 50 having the same length in the reciprocating direction are compared, the piston 50 in which the distance L1 is shorter than the distance L2 can have a longer length on the dashed double-dashed line than the piston 50 in which the distance L1 is equal to or greater than the distance L2. Therefore, when the piston 50 of the hydraulic control unit 1 has the groove portion 54, the hydraulic control unit 1 in which the distance L1 is shorter than the distance L2 can be made smaller.

[0066]

[0046] As shown in Figures 3 and 4, in the hydraulic control unit 1 according to this embodiment, the end 14b of the secondary flow path 14 opens to the inner circumferential surface 45 of the cylinder chamber 40. In the case of the hydraulic control unit 1 in which the end 14b of the secondary flow path 14 opens to the inner circumferential surface 45 and the piston 50 is provided with the groove portion 54, preferably, when the piston 50 has moved to the end of its movement on the liquid reservoir portion 41 side, the end 56 of the groove portion 54 on the liquid reservoir portion 41 side faces the end 14b of the secondary flow path 14. In a hydraulic control unit 1 having this configuration, the length of the piston 50 in the reciprocating direction can be made shorter than when the end 56 is positioned closer to the spring accommodating section 42 than the end 14b when the piston 50 has moved to the end of its movement on the liquid reservoir section 41 side. Therefore, the hydraulic control unit 1 having this configuration can be made smaller.

[0067]

[0047] In this case, preferably, when the piston 50 has moved to the end of its movement on the liquid reservoir 41 side, the center 32a of the ring 32 in the reciprocating direction of the piston 50 is located in an area on the spring accommodating section 42 side, with the end 14b of the sub-flow path 14 as the reference point. In the hydraulic control unit 1 configured in this manner, when a configuration is adopted in which the end 56 of the groove 54 faces the end 14b of the sub-flow path 14, it is possible to prevent the ring 32 from interfering with and being damaged by the edge of the end 14b of the sub-flow path 14, and the reliability of the hydraulic control unit 1 is improved.

[0068]

[0048] Furthermore, when the end 14b of the sub-flow path 14 opens to the inner circumferential surface 45 of the cylinder chamber 40, the center 14c of the end 14b of the sub-flow path 14 is preferably located in an area on the liquid reservoir 41 side with respect to the central axis of the release valve 22. Specifically, in this embodiment, the base 10 has a release valve recess 17 into which the release valve 22 is inserted. That is, the central axis 17a of the release valve recess 17 becomes the central axis of the release valve 22. The center 14c of the end 14b of the sub-flow path 14 is located in an area on the liquid reservoir 41 side with respect to the central axis 17a. The hydraulic control unit 1 configured in this manner can shorten the length of the piston 50 in the reciprocating direction of the piston 50, thereby making the hydraulic control unit 1 more compact.

[0069]

[0049] When the hydraulic control unit 1 is provided with a return flow path 15, it preferably includes a check valve 23, as shown in FIG. 2, provided in the return flow path 15 to regulate the flow of brake fluid from the master cylinder 242 to the fluid reservoir 41. The hydraulic control unit 1 provided with the return flow path 15 requires a mechanism to regulate the flow of brake fluid from the master cylinder 242 through the return flow path 15 to the fluid reservoir 41 of the accumulator 30 when the brake lever 241 is operated by the driver. When an opening / closing valve is provided in the return flow path 15 as the mechanism, the control device 80 controls the opening / closing state of the opening / closing valve based on the pressure of the brake fluid in the master cylinder 242. That is, when an on-off valve is provided in the return flow path 15 as the mechanism, the hydraulic control unit 1 needs to be provided with a hydraulic pressure detection sensor that detects the pressure of the brake fluid in the master cylinder 242. On the other hand, when the check valve 23 is provided in the return flow path 15, the check valve 23 mechanically switches between an open and closed state depending on the difference between the pressure of the brake fluid in the fluid reservoir 41 and the pressure of the brake fluid in the master cylinder 242. Therefore, when the hydraulic control unit 1 is provided with the return flow path 15, by providing the check valve 23 in the return flow path 15, it can be configured without a hydraulic pressure detection sensor that detects the pressure of the brake fluid in the master cylinder 242. Therefore, when the hydraulic control unit 1 has a return flow path 15, the manufacturing cost of the hydraulic control unit 1 can be reduced by providing a check valve 23 in the return flow path 15.

[0070] Preferably, the protrusion 51 has a tapered shape that becomes thinner from the base to the tip 52. For example, the protrusion 51 has a conical or truncated conical shape. When the piston 50 reciprocates in the cylinder chamber 40, the central axis of the piston 50 may be tilted with respect to the reciprocating direction of the piston 50. In this case, if the protrusion 51 has a tapered shape that becomes thinner from the base to the tip 52, it is possible to prevent the tip 52 of the protrusion 51 from getting caught on the spring 31. Therefore, a hydraulic control unit 1 having a tapered protrusion 51 that becomes thinner from the base to the tip 52 has improved reliability.

[0071] [ 0 0 5 1 ]

[0072] <Modification> Fig. 5 is a side view, partially in cross section, of a base portion of a modification of a hydraulic control unit according to the present invention. The piston 50 of the hydraulic control unit 1 shown in Fig. 5 has a sliding protrusion 58 that protrudes into the spring accommodating portion 42. The sliding protrusion 58 is provided on the outer periphery of the spring 31. When the piston 50 reciprocates in the cylinder chamber 40, the sliding protrusion 58 slides on the inner periphery 45 of the cylinder chamber 40. The sliding protrusion 58 has, for example, a hollow cylindrical shape. In addition, in the reciprocating direction of the piston 50, the distance between the protrusion 51 and the spring accommodating portion side end 44 is shorter than the distance between the sliding protrusion 58 and the spring accommodating portion side end 44. In other words, when the piston 50 has moved to the end of its movement on the spring accommodating portion 42 side, the sliding convex portion 58 does not come into contact with the end portion 44 on the spring accommodating portion side.

[0073]

[0052] When the piston 50 reciprocates in the cylinder chamber 40, the outer peripheral surface 53 of the piston 50 slides on the inner peripheral surface 45 of the cylinder chamber 40. In order for the piston 50 to reciprocate smoothly in the cylinder chamber 40, the portion of the piston 50 that slides on the inner peripheral surface 45 of the cylinder chamber 40 needs to have a specified length in the reciprocating direction of the piston 50. Here, when the piston 50 is provided with the sliding protrusion 58, the length of the piston 50 in the reciprocating direction can be shortened compared to when the piston 50 does not have the sliding protrusion 58, and the above-mentioned specified length of the part of the piston 50 that slides on the inner circumferential surface 45 of the cylinder chamber 40 can be ensured. Therefore, the hydraulic control unit 1 having the piston 50 that is provided with the sliding protrusion 58 can be While an example of a hydraulic control unit according to the present invention has been described above in the embodiment, the hydraulic control unit according to the present invention is not limited to the description of the embodiment. For example, the hydraulic control unit according to the present invention may be implemented with only a part of the description of the embodiment. Furthermore, conventional hydraulic control units for saddle-ride vehicles include a pump that returns brake fluid stored in a reservoir of an accumulator to a master cylinder and a motor that drives the pump. The hydraulic control unit according to the present invention may be configured with such a pump and motor.

[0074] [Explanation of symbols]

[0075] [ 0 0 5 9 ]

[0076] 1 hydraulic control unit, 10 base, 11 master cylinder port, 12 wheel cylinder port, 13 main flow path, 13a midway portion, 13b midway portion, 14 sub-flow path, 14a end, 14b end, 14c center, 15 return flow path, 15a end, 15b end, 16 accumulator recess, 17 release valve recess, 17a central axis, 18 cover, 21 inlet valve, 22 release valve, 23 check valve, 30 accumulator, 31 spring, 32 ring, 32a center, 40 cylinder chamber, 41 fluid reservoir portion, 42 spring accommodating portion, 43 Fluid reservoir side end, 44 Spring accommodating side end, 45 Inner peripheral surface, 5〇 Piston, 51 Convex portion, 52 Tip portion, 53 Outer peripheral surface, 54 Groove portion, 55 Bottom portion, 56 End portion, 58 Sliding convex portion, 8〇 Control device, 100 Brake system, 101 Fluid pipe, 102 Fluid pipe, 103 Fluid pressure detection sensor, 200 Saddle-ride type vehicle, 210 Frame, 211 Head tube, 21

[0077] 2 Top tube, 2 1 3 Down tube, 2 1 4 Seat tube, 2 1 5 Stem, 2 1 6 Front fork, 2 1 ? Front wheel, 2 1 8 Saddle, 2 1 9 Pedals, 2 2 〇 Rear wheel, 2 3 0 Swivel part, 2 3 1 Steering column, 2 3 2 Handle stem, 2

[0078] 33 Handlebar, 240 Brake operating section, 241 Brake lever, 242 Master cylinder, 243 Reservoir, 250 Front wheel braking section, 251 Wheel cylinder, 252 Rotor, 260 Rear wheel braking section, 270 Power supply unit.

Claims

[Document name] Scope of claims

1. A hydraulic control unit (1) for a brake system (100) mounted on a saddle-ride type vehicle (200) and capable of performing antilock brake control, comprising: a main flow path (13) that connects a master cylinder (242) and a wheel cylinder (251); an inlet valve (21) provided in the main flow path (13) for opening and closing the main flow path (13); a sub-flow path (14) having one end (14a) connected to an area of ​​the main flow path (13) that is on the wheel cylinder (251) side with respect to the inlet valve (21); and a release valve provided in the sub-flow path (14) for opening and closing the sub-flow path (14). and an accumulator (30) connected to the other end (14b) of the sub-flow path (14) and storing the brake fluid that has flowed into the sub-flow path (14) from the wheel cylinder (251). The accumulator (30) comprises: a cylinder chamber (40) connected to the other end (14b) of the sub-flow path (14); and a piston (50) reciprocally provided in the cylinder chamber (40) and dividing the interior of the cylinder chamber (40) into a fluid reservoir section (41) connected to the other end (14b) of the sub-flow path (14) and storing the brake fluid, and a spring accommodating section (42). and a spring (31) accommodated in the spring accommodating portion (42) to press the piston (50) toward the fluid reservoir portion (41) and push the brake fluid stored in the fluid reservoir portion (41) out of the fluid reservoir portion (41), wherein the piston (50) protrudes into the spring accommodating portion (42) and is inserted into the inner circumferential side of the spring (31), and when the piston (50) moves in a direction in which the fluid reservoir portion (41) expands, a spring accommodating portion side end portion (The hydraulic pressure control unit (1) has a protrusion (51) that serves as a stopper when the tip end (52) abuts against the protrusion (51) of the hydraulic pressure control unit (44).

2. The hydraulic control unit (1) according to claim 1, wherein the piston (50) has a sliding protrusion (58) that protrudes into the spring accommodating portion (42) and is provided on the outer circumferential side of the spring (31), and slides on an inner circumferential surface (45) of the cylinder chamber (40) that extends along the reciprocating direction of the piston (50).

3. The hydraulic control unit (1) according to claim 2, wherein a distance between the convex portion (51) and the spring accommodating portion side end (44) in the reciprocating direction of the piston (50) is shorter than a distance between the sliding convex portion (58) and the spring accommodating portion side end (44).

4. The piston (50) has an outer peripheral surface (53) extending along the reciprocating direction of the piston (50) with a groove (54) for accommodating a ring (32) that seals between an inner peripheral surface (45) of the cylinder chamber (40) extending along the reciprocating direction and the outer peripheral surface (53), and a distance (L1) between the inner peripheral surface (45) and a bottom S (55) of the groove (54) in a direction perpendicular to the reciprocating direction is shorter than a distance (L2) between the convex portion (51) and the inner peripheral surface (45).

5. The other end (14b) of the sub-flow path (14) is open to an inner circumferential surface (45) of the cylinder chamber (40) extending along the reciprocating direction of the piston (50), and the piston (50) has an outer circumferential surface (53) extending along the reciprocating direction, and the inner circumferential surface (54) of the cylinder chamber (40) is open to the outer circumferential surface (53) of the piston (50) extending along the reciprocating direction. a groove (54) for accommodating a ring (32) that seals between the outer peripheral surface (53) and the surface (45) of the piston (50), and an end (56) of the groove (54) on the liquid reservoir (41) side faces the other end (14b) of the sub-flow path (14) when the piston (50) has moved to the end of movement on the liquid reservoir (41) side.

6. The hydraulic control unit (1) according to claim 5, wherein, when the piston (50) has moved to the end of movement on the liquid reservoir portion (41) side, the center (32a) of the O-ring (32) in the reciprocating direction is located in an area on the spring accommodating portion (42) side, with the other end (14b) of the sub-flow path (14) as a reference. [Claim ?] The hydraulic control unit (1) according to claim 5, wherein a center (14c) of the other end (14b) of the sub-flow path (14) is located in an area on the liquid reservoir (41) side with respect to a central axis (17a) of the release valve (22).

8. The hydraulic control unit (1) according to any one of claims 1 to 3, comprising: a return flow path (15) that connects the fluid reservoir (41) and the master cylinder (242); and a check valve (23) that is provided in the return flow path (15) and that regulates the flow of brake fluid from the master cylinder (242) toward the fluid reservoir (41).

9. The hydraulic control unit (1) according to claim 8, wherein the hydraulic control unit (1) does not include a hydraulic pressure detection sensor that detects the pressure of the brake fluid in the master cylinder (242). [Claim 1 ○] A hydraulic control unit (1) according to any one of claims 1 to 3, wherein the brake fluid that has flowed from the wheel cylinder (251) into the fluid reservoir (41) is returned to the master cylinder (242) by a pump press.

11. A hydraulic control unit (1) according to any one of claims 1 to 3, wherein the convex portion (51) has a tapered shape that narrows from the base portion toward the tip portion (52). [Claim 1 2] A saddle-ride type vehicle (200) equipped with a hydraulic pressure control unit (1) according to any one of claims 1 to 3.

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