JP5012820B2 - Brake control device - Google Patents

Description

  The present invention relates to a brake control device that controls braking force applied to wheels provided in a vehicle.

  For example, Patent Document 1 describes a brake control device using a so-called brake-by-wire. The brake-by-wire detects the driver's braking operation as a braking request and generates a braking force requested by the driver through electronic control. In this brake control device, it is possible to execute regenerative cooperative control that gives the required braking force by the sum of the regenerative braking force and the hydraulic braking force. The combined use of the regenerative braking force improves the fuel efficiency of the vehicle. Further, in this brake control device, it is possible to control each wheel cylinder pressure in common by a pair of linear control valves, and from the viewpoint of cost reduction compared to providing a linear control valve for each wheel cylinder. preferable.

  In this brake control device, when the regenerative braking force reaches the maximum value, the control of the pressure increase control valve is stopped, and the hydraulic pressure is obtained from the regulator instead. By providing the differential pressure valve downstream of the regulator, the hydraulic pressure corresponding to the maximum regenerative braking force can be reduced from the regulator pressure and supplied to the wheel cylinder. Thereby, the operation frequency of the pressure increase control valve can be reduced and the durability can be improved.

JP 2007-153206 A

  In the brake-by-wire, the master cylinder and the wheel cylinder are separated in response to a braking request, and the wheel cylinder can be controlled to a hydraulic pressure different from that of the master cylinder. In some cases, the wheel cylinder pressure is controlled to be considerably higher than the master cylinder pressure (for example, several times to 10 times). This high pressure is usually introduced from a high pressure hydraulic source including, for example, an accumulator. Therefore, the pressurization by the driver's stepping force in the master cylinder cannot be used for the pressure increase of the wheel cylinder.

  Therefore, an object of the present invention is to provide a brake control device that controls the wheel cylinder pressure by effectively utilizing the hydraulic fluid pressure applied by the driver's pedaling force.

  A brake control device according to an aspect of the present invention includes a plurality of wheel cylinders that apply a braking force to each of a plurality of wheels according to a hydraulic fluid pressure, a power hydraulic pressure source that accumulates hydraulic fluid by supplying power, A master cylinder that pressurizes the stored hydraulic fluid in accordance with a defined brake pedal stroke and hydraulic fluid pressure, and the hydraulic fluid source is used as a high pressure source to adjust the hydraulic fluid according to the hydraulic fluid pressure of the master cylinder. A manual hydraulic pressure source including a regulator for pressure, and a hydraulic fluid flow path connecting the manual hydraulic pressure source and the plurality of wheel cylinders in parallel. A wheel cylinder pressure control system that controls the upstream pressure common to the wheel cylinders, and calculates the common upstream pressure according to the stroke to generate the calculated upstream pressure. And a control unit for controlling the wheel cylinder pressure control system. The control unit lowers the upstream pressure generated by the wheel cylinder pressure control system from the hydraulic fluid pressure obtained according to the relationship between the stroke and the hydraulic fluid pressure in the manual hydraulic pressure source.

  According to this aspect, in a brake system having a manual hydraulic power source and a power hydraulic pressure source as parallel hydraulic pressure sources for a plurality of wheel cylinders, the wheel cylinder upstream pressure as the control hydraulic pressure is higher than the manual hydraulic pressure source. Low pressure. For this reason, a manual hydraulic pressure source can be used when further pressurization is required for the control hydraulic pressure. Therefore, the hydraulic fluid pressure applied by the driver's pedaling force can also be effectively used for wheel cylinder pressure control.

  The control unit may calculate the common upstream pressure in accordance with a relationship between the stroke and the hydraulic fluid pressure that increases the hydraulic fluid pressure and decreases the increase rate of the hydraulic fluid pressure as the stroke increases. When the stroke is small, the upstream pressure of the wheel cylinder is higher than the hydraulic pressure in the manual hydraulic pressure source when the stroke is small. The relationship may be such that the hydraulic pressure changes linearly according to the stroke, with an inclination set so that the upstream pressure of the wheel cylinder is lower than the hydraulic pressure in the hydraulic pressure source.

  According to this aspect, a manual hydraulic pressure source can be used for pressurization when the stroke is large, and a desired control hydraulic pressure can be applied when the stroke is small. Therefore, the high pressure of the manual hydraulic pressure source due to the driver's large stroke can be effectively used, and the brake feeling when the stroke is small can be adjusted more preferably. Further, in the manual hydraulic pressure source, since the working hydraulic pressure can be linearly changed according to the stroke, the manual hydraulic pressure source can be manufactured relatively easily, which contributes to cost reduction.

  The control unit may make the upstream pressure of the wheel cylinder lower than the working hydraulic pressure in the manual hydraulic pressure source in a stroke larger than a predetermined stroke.

  According to this aspect, the manual hydraulic pressure source can be used for pressurization when the stroke is large, that is, when a large hydraulic pressure is required. Thereby, the control flow volume in a wheel cylinder pressure control system can also be reduced. Therefore, the driver's pedaling force can be utilized, and the wheel cylinder pressure control system can be reduced in size and energy can be saved.

  The control unit may make the upstream pressure of the wheel cylinder higher than the hydraulic hydraulic pressure in the manual hydraulic pressure source at least during an idle stroke.

  According to this aspect, it is possible to more preferably adjust the brake feeling in a relatively small stroke range including the idle stroke.

  You may further provide the regulator cut valve provided in the hydraulic fluid flow path which connects the said regulator and these wheel cylinders. The controller determines whether or not the upstream pressure should be controlled with higher responsiveness than normal, and when it is determined that the control should be performed with high responsiveness, the control of the wheel cylinder pressure control system is stopped. The hydraulic fluid may be supplied to the wheel cylinder through the regulator cut valve.

  According to this aspect, when high responsiveness is required for the control hydraulic pressure, for example, sudden braking or ABS control, a high regulator pressure can be applied to the wheel cylinder through the regulator cut valve. Therefore, the wheel cylinder pressure can be controlled with good responsiveness.

  You may further provide the regulator cut valve provided in the hydraulic fluid flow path which connects the said regulator and these wheel cylinders. The control unit controls the upstream pressure by the wheel cylinder pressure control system when the target value of the common upstream pressure during ABS control is smaller than a predetermined value, and the target value is larger than the predetermined value. Alternatively, the upstream pressure may be controlled by controlling the regulator cut valve.

  According to this aspect, the hydraulic pressure source for ABS control is switched between the high stroke region and the low stroke region. That is, the regulator is selected in the high stroke region, and the power hydraulic pressure source is selected in the low stroke region. Thereby, ABS control can be established even in a low stroke region. In addition, since the regulator is selected in the high stroke region, the operation frequency of the wheel cylinder pressure control system is reduced.

  Another aspect of the present invention is also a brake control device. This device includes a manual hydraulic pressure source that pressurizes hydraulic fluid according to a first relationship between a stroke of a brake pedal and hydraulic fluid pressure, and a second relationship between a stroke and hydraulic fluid pressure that is different from the first relationship. And a control unit that controls the hydraulic fluid pressure to be applied to the wheel cylinder. The hydraulic fluid pressure obtained according to the second relationship according to the stroke was made lower than the hydraulic fluid pressure obtained according to the first relationship according to the stroke.

  According to this aspect, the hydraulic pressure generated in the manual hydraulic pressure source by the driver's brake operation becomes higher than the control hydraulic pressure. Therefore, the hydraulic fluid pressure that is pressurized by the driver's pedaling force can be effectively utilized for further pressurization of the control hydraulic pressure.

  According to the present invention, the hydraulic fluid pressure that is pressurized by the driver's pedaling force can also be effectively used for wheel cylinder pressure control.

It is a systematic diagram showing a brake control device according to each embodiment of the present invention. It is a figure which shows the relationship between the brake pedal stroke in 1st Example, and hydraulic fluid pressure. It is a figure which shows the relationship between the brake pedal stroke and hydraulic fluid pressure in a 2nd Example.

  According to one embodiment of the present invention, the brake control device may be configured such that the wheel cylinder pressure is lower than the hydraulic fluid pressure that is pressurized according to the brake pedal stroke in the master cylinder with a hydraulic booster. Good. That is, the hydraulic pressure of the master cylinder with a hydraulic booster may be higher than the wheel cylinder pressure. Therefore, in addition to a high pressure source for controlling the wheel cylinder pressure, a master cylinder with a hydraulic booster can be used as a spare high pressure source. For this reason, the master cylinder pressure pressurized by the driver's stepping force can also be effectively utilized for wheel cylinder pressure control.

  The brake control device may include a manual hydraulic pressure source that pressurizes the stored hydraulic fluid in accordance with a driver's brake operation input. The manual hydraulic pressure source pressurizes the stored hydraulic fluid according to a driver's brake operation input, for example, a first relationship between the brake pedal stroke and the hydraulic pressure. The manual hydraulic pressure source may include a master cylinder that pressurizes the stored hydraulic fluid according to a driver's brake operation input, and a regulator that regulates the hydraulic fluid according to the hydraulic pressure of the master cylinder. The manual hydraulic pressure source may include a hydraulic booster that generates a hydraulic pressure obtained by amplifying the driver's brake operation input by a predetermined boost ratio. In this case, the driver's brake operation input is amplified to generate a master cylinder pressure and a regulator pressure.

  In addition, the brake control device has a wheel cylinder pressure control system for controlling the hydraulic fluid pressure to be applied to the wheel cylinder, using a hydraulic power source that boosts the hydraulic fluid by supplying power and stores high-pressure hydraulic fluid as a high-pressure source. You may prepare. The hydraulic fluid pressure to be applied to the wheel cylinder may be the wheel cylinder pressure itself or a wheel cylinder upstream pressure common to a plurality of wheel cylinders. The power hydraulic pressure source may be connected to the regulator so as to be used as a high pressure source for regulating pressure in the regulator. A control valve for applying a control hydraulic pressure to the wheel cylinder using the power hydraulic pressure source as a high pressure source may be provided between the power hydraulic pressure source and the wheel cylinder. The brake control device may separate the manual hydraulic pressure source from the wheel cylinder during control by the wheel cylinder pressure control system. For example, the brake control device may include a control unit that closes a control valve provided in a flow path connecting the manual hydraulic pressure source and the wheel cylinder during control by the wheel cylinder pressure control system.

  The brake control device may include a control unit that controls the hydraulic fluid pressure to be applied to the wheel cylinder in accordance with the second relationship between the brake pedal stroke and the hydraulic fluid pressure. The control unit may control the wheel cylinder pressure control system based on the second relationship. The second relationship may be different from or the same as the first relationship between the stroke and the hydraulic pressure in the manual hydraulic pressure source. By separately setting the first relationship and the second relationship, it is possible to achieve both cost and performance more efficiently. For example, the first relationship can be set with emphasis on ease of manufacture of the manual hydraulic pressure source, and the second relationship can be set with emphasis on brake feeling.

  The brake control device may be configured such that the hydraulic fluid pressure obtained according to the second relationship is lower than the hydraulic fluid pressure obtained according to the first relationship in the manual hydraulic pressure source. In this case, the first relationship and the second relationship may be set so that the second relationship gives a lower hydraulic fluid pressure than the first relationship over the entire stroke range of the brake pedal. Alternatively, the second relationship gives a lower hydraulic fluid pressure than the first relationship over a predetermined stroke range, and the second relationship gives a higher hydraulic fluid pressure than the first relationship outside the range. The 1st and 2nd relationship may be set. In other words, the first profile representing the relationship between the stroke and the fluid pressure in the manual fluid pressure source and the second profile representing the relationship between the stroke and the control fluid pressure have the first intersection so as to have at least one intersection. And the 2nd profile may be set up.

  The first profile may be set to a stroke-hydraulic pressure characteristic in which the hydraulic fluid pressure changes substantially linearly according to the stroke. In this case, the first profile can be expressed by a linear function. Alternatively, the first profile may be non-linear. The first profile is determined in consideration of, for example, ease of manufacturing a manual hydraulic pressure source and brake feeling. When the first profile is linear, the first profile may not have a constant inclination over the entire stroke range, but may have a polygonal characteristic, that is, a characteristic in which the inclination changes stepwise. In this case, for example, it may have a relatively large first inclination below a predetermined stroke and a relatively small second inclination above that stroke. That is, as the stroke increases, the hydraulic fluid pressure increases relatively abruptly in the stroke range of the first slope, and the hydraulic fluid pressure increases relatively slowly in the stroke range of the second slope. One profile may be set. Note that since a so-called idle stroke is normally set for the manual hydraulic pressure source, no hydraulic pressure is generated in this idle stroke range.

  On the other hand, the second profile may be adjusted to give a desired brake feeling. The second profile may be set to a stroke-hydraulic pressure characteristic in which the hydraulic fluid pressure changes substantially in a curve according to the stroke. For example, the second profile may be set such that the hydraulic fluid pressure increases and the hydraulic fluid pressure increase rate decreases as the stroke increases. Alternatively, the second profile may be obtained by applying a predetermined differential pressure to the first profile. That is, the second profile may be obtained by subtracting a predetermined pressure from the first profile.

  Typically, in both the first and second profiles, the hydraulic pressure increases monotonically as the stroke increases. If the rate of increase in hydraulic fluid pressure decreases as the stroke of the second profile increases, the hydraulic fluid pressure in the small profile range is lower than that of the first profile in the small stroke range. The hydraulic pressure of the second profile is lower than that of the first profile. That is, the first profile and the second profile can have no intersection.

  Further, if the first and second profiles are set so that the second profile gives a higher hydraulic pressure than the first profile in the small stroke range, the magnitude relationship can be reversed in the large stroke range. That is, the first profile and the second profile have an intersection. The second profile gives a higher hydraulic pressure than the first profile at a stroke smaller than the stroke at the intersection, and the second profile gives a lower hydraulic pressure than the first profile at a stroke larger than the intersection stroke. It will be. By setting the hydraulic fluid pressure in the first and second profiles to the same level (for example, 0.5 to 2 times), the intersection stroke can be set smaller than the maximum pedal stroke. In this way, the control hydraulic pressure can be made higher than the manual hydraulic pressure source in the stroke range below the intersection stroke, and the control hydraulic pressure can be made lower than the manual hydraulic pressure source in the stroke range exceeding the intersection stroke.

  Conversely, the first and second profiles are set so that the second profile gives a lower pressure than the first profile in the small stroke range, and the second profile gives a higher pressure than the first profile in the large stroke range. It may be set. That is, the control hydraulic pressure may be lower than the manual hydraulic pressure source when the stroke is small, and the control hydraulic pressure may be higher than the manual hydraulic pressure source when the stroke is large. For example, when it is ensured that the regenerative braking force can be used in the small stroke region, the control hydraulic pressure can be reduced when the stroke is small.

  Note that the first and second profiles may be set so that the first profile and the second profile have a plurality of intersections. For example, when the first profile has a polygonal line characteristic, the first profile and the second profile may have a plurality of intersections.

  The brake control device may be configured to generate the required braking force by using both the hydraulic braking force and the regenerative braking force. The brake control device may include a regenerative braking unit that generates a regenerative braking force by regenerative control of the electric motor, and a hydraulic brake unit that generates a hydraulic braking force by supplying hydraulic fluid from a hydraulic pressure source.

  In this case, the brake control device may include a control unit that controls the control hydraulic pressure to be lower than the manual hydraulic pressure source in a predetermined stroke range regardless of whether or not the regenerative braking force is used. The control unit controls the control hydraulic pressure, which would be necessary when the required braking force is satisfied with the hydraulic braking force without using the regenerative braking force, to be lower than the manual hydraulic pressure source within a predetermined stroke range. Also good. That is, the control unit may set the maximum value of the control hydraulic pressure required when the required braking force is satisfied only by the hydraulic braking force to be lower than the manual hydraulic pressure source within a predetermined stroke range.

  In addition, the brake control device includes a first path for supplying hydraulic pressure from a high pressure source to the wheel cylinder through the first control valve, and a master cylinder adjusted according to a brake pedal stroke using the hydraulic pressure of the high pressure source. And a second path for supplying pressure to the wheel cylinder through the second control valve. The brake control device may further include target hydraulic pressure determining means for determining the target hydraulic pressure, and determination means for determining whether or not the target hydraulic pressure is equal to or higher than a predetermined value. The brake control device may further include means for selecting supply of hydraulic pressure from the second path when it is determined that the target hydraulic pressure is greater than or equal to a predetermined value. On the other hand, the brake control device may select the hydraulic pressure supply from the first path when it is determined that the target hydraulic pressure is less than the predetermined value.

  In this way, when the pressure is to be greatly increased, the driver's pedaling force can be effectively utilized using the master cylinder pressure. By using the first path and the second path properly, the frequency of use can be distributed to the first control valve and the second control valve. In particular, by restricting the use of the first path and the first control valve to a normal case that does not require large pressurization, the flow rate and the operation frequency of the first path and the first control valve can be reduced. Therefore, it is possible to reduce the size of the first path and the first control valve, save energy, and improve durability.

  FIG. 1 is a system diagram showing a brake control device 20 according to each embodiment of the present invention. A brake control device 20 shown in the figure constitutes an electronically controlled brake system (ECB) for a vehicle, and controls braking force applied to four wheels provided on the vehicle. The brake control device 20 according to the present embodiment is mounted on, for example, a hybrid vehicle that includes an electric motor and an internal combustion engine as a travel drive source. In such a hybrid vehicle, each of regenerative braking that brakes the vehicle by regenerating kinetic energy of the vehicle into electric energy and hydraulic braking by the brake control device 20 can be used for braking the vehicle. The vehicle in the present embodiment can execute brake regenerative cooperative control that generates a desired braking force by using both the regenerative braking and the hydraulic braking together.

  As shown in FIG. 1, the brake control device 20 includes disc brake units 21FR, 21FL, 21RR and 21RL provided for each wheel, a master cylinder unit 27, a power hydraulic pressure source 30, a hydraulic pressure, Actuator 40.

  Disc brake units 21FR, 21FL, 21RR, and 21RL apply braking force to the right front wheel, the left front wheel, the right rear wheel, and the left rear wheel of the vehicle, respectively. The master cylinder unit 27 as the manual hydraulic pressure source in the present embodiment sends the brake fluid pressurized according to the operation amount by the driver of the brake pedal 24 as the brake operation member to the disc brake units 21FR to 21RL. To do. The power hydraulic pressure source 30 can send the brake fluid as the working fluid pressurized by the power supply to the disc brake units 21FR to 21RL independently from the operation of the brake pedal 24 by the driver. is there. The hydraulic actuator 40 appropriately adjusts the hydraulic pressure of the brake fluid supplied from the power hydraulic pressure source 30 or the master cylinder unit 27 and sends it to the disc brake units 21FR to 21RL. Thereby, the braking force with respect to each wheel by hydraulic braking is adjusted.

  Each of the disc brake units 21FR to 21RL, the master cylinder unit 27, the power hydraulic pressure source 30, and the hydraulic actuator 40 will be described in more detail below. Each of the disc brake units 21FR to 21RL includes a brake disc 22 and wheel cylinders 23FR to 23RL incorporated in the brake caliper, respectively. The wheel cylinders 23FR to 23RL are connected to the hydraulic actuator 40 via different fluid passages. Hereinafter, the wheel cylinders 23FR to 23RL are collectively referred to as “wheel cylinders 23” as appropriate.

  In the disc brake units 21FR to 21RL, when brake fluid is supplied to the wheel cylinder 23 from the hydraulic actuator 40, a brake pad as a friction member is pressed against the brake disc 22 that rotates together with the wheel. Thereby, a braking force is applied to each wheel. In this embodiment, the disc brake units 21FR to 21RL are used, but other braking force applying mechanisms including a wheel cylinder 23 such as a drum brake may be used.

  In this embodiment, the master cylinder unit 27 is a master cylinder with a hydraulic booster, and includes a hydraulic booster 31, a master cylinder 32, a regulator 33, and a reservoir. The hydraulic booster 31 is connected to the brake pedal 24, amplifies the pedal effort applied to the brake pedal 24, and transmits it to the master cylinder 32. When the brake fluid is supplied from the power hydraulic pressure source 30 to the hydraulic pressure booster 31 via the regulator 33, the pedal effort is amplified. The master cylinder 32 generates a master cylinder pressure having a predetermined boost ratio with respect to the pedal effort.

  A reservoir 34 for storing brake fluid is disposed above the master cylinder 32 and the regulator 33. The master cylinder 32 communicates with the reservoir 34 when the depression of the brake pedal 24 is released. On the other hand, the regulator 33 is in communication with both the reservoir 34 and the accumulator 35 of the power hydraulic pressure source 30, and the reservoir 34 is used as a low pressure source, the accumulator 35 is used as a high pressure source, and the hydraulic pressure is approximately equal to the master cylinder pressure. Is generated. Hereinafter, the hydraulic pressure in the regulator 33 is appropriately referred to as “regulator pressure”. The master cylinder pressure and the regulator pressure do not need to be exactly the same pressure. For example, the master cylinder unit 27 can be designed so that the regulator pressure is slightly higher.

  The master cylinder 32 and the regulator 33 have a so-called idle stroke. The idle stroke is a stroke from when the brake operation is not performed until the brake pedal 24 is depressed and the connection between the master cylinder 32 and the regulator 33 and the reservoir 34 is cut off. During the idle stroke, the fluid pressure in the master cylinder 32 and the regulator 33 does not increase because the reservoir 34 is in communication. The master cylinder unit 27 of the present embodiment is configured such that when the brake pedal is depressed, the idle stroke of the regulator 33 is first reduced as the stroke increases, and then the idle stroke of the master cylinder 32 is reduced. That is, the connection with the reservoir 34 is cut off in the order of the regulator 33 and the master cylinder 32.

  The power hydraulic pressure source 30 includes an accumulator 35 and a pump 36. The accumulator 35 converts the pressure energy of the brake fluid boosted by the pump 36 into the pressure energy of an enclosed gas such as nitrogen, for example, about 14 to 22 MPa and stores it. The pump 36 has a motor 36 a as a drive source, and its suction port is connected to the reservoir 34, while its discharge port is connected to the accumulator 35. The accumulator pressure is maintained within a set range to be maintained by the pump 36 (this may be referred to as an allowable range in the present specification). Based on the measurement value of the accumulator pressure sensor 72, the brake ECU 70 turns on the pump 36 to increase the accumulator pressure when the accumulator pressure falls below the lower limit of the allowable range, and when the accumulator pressure exceeds the upper limit of the allowable range. The pressurization is finished by turning off the pump 36.

  The accumulator 35 is also connected to a relief valve 35 a provided in the master cylinder unit 27. When the pressure of the brake fluid in the accumulator 35 increases abnormally to about 25 MPa, for example, the relief valve 35 a is opened, and the high-pressure brake fluid is returned to the reservoir 34.

  As described above, the brake control device 20 includes the master cylinder 32, the regulator 33, and the accumulator 35 as a supply source of brake fluid to the wheel cylinder 23. A master pipe 37 is connected to the master cylinder 32, a regulator pipe 38 is connected to the regulator 33, and an accumulator pipe 39 is connected to the accumulator 35. These master pipe 37, regulator pipe 38 and accumulator pipe 39 are each connected to a hydraulic actuator 40.

  The hydraulic actuator 40 includes an actuator block in which a plurality of flow paths are formed, and a plurality of electromagnetic control valves. The flow paths formed in the actuator block include individual flow paths 41, 42, 43 and 44 and a main flow path 45. The individual flow paths 41 to 44 are respectively branched from the main flow path 45 and connected to the wheel cylinders 23FR, 23FL, 23RR, 23RL of the corresponding disc brake units 21FR, 21FL, 21RR, 21RL. Thereby, each wheel cylinder 23 can communicate with the main flow path 45.

  In addition, ABS holding valves 51, 52, 53 and 54 are provided in the middle of the individual flow paths 41, 42, 43 and 44. Each of the ABS holding valves 51 to 54 has a solenoid and a spring that are ON / OFF controlled, and both are normally open electromagnetic control valves that are opened when the solenoid is in a non-energized state. Each of the ABS holding valves 51 to 54 in the opened state can distribute the brake fluid in both directions. That is, the brake fluid can flow from the main flow path 45 to the wheel cylinder 23, and conversely, the brake fluid can also flow from the wheel cylinder 23 to the main flow path 45. When the solenoid is energized and the ABS holding valves 51 to 54 are closed, the flow of brake fluid in the individual flow paths 41 to 44 is blocked.

  Further, the wheel cylinder 23 is connected to the reservoir channel 55 via pressure reducing channels 46, 47, 48 and 49 connected to the individual channels 41 to 44, respectively. ABS decompression valves 56, 57, 58 and 59 are provided in the middle of the decompression channels 46, 47, 48 and 49. Each of the ABS pressure reducing valves 56 to 59 has a solenoid and a spring that are ON / OFF controlled, and is a normally closed electromagnetic control valve that is closed when the solenoid is in a non-energized state. When the ABS pressure reducing valves 56 to 59 are closed, the flow of brake fluid in the pressure reducing flow paths 46 to 49 is blocked. When the solenoid is energized and the ABS pressure reducing valves 56 to 59 are opened, the brake fluid is allowed to flow through the pressure reducing flow paths 46 to 49, and the brake fluid flows from the wheel cylinder 23 to the pressure reducing flow paths 46 to 49 and It returns to the reservoir 34 via the reservoir channel 55. The reservoir channel 55 is connected to the reservoir 34 of the master cylinder unit 27 via a reservoir pipe 77.

  The main channel 45 has a separation valve 60 in the middle. By this separation valve 60, the main channel 45 is divided into a first channel 45 a connected to the individual channels 41 and 42 and a second channel 45 b connected to the individual channels 43 and 44. The first flow path 45a is connected to the front wheel wheel cylinders 23FR and 23FL via the individual flow paths 41 and 42, and the second flow path 45b is connected to the rear wheel wheel cylinder via the individual flow paths 43 and 44. Connected to 23RR and 23RL.

  The separation valve 60 has a solenoid and a spring that are ON / OFF controlled, and is a normally closed electromagnetic control valve that is closed when the solenoid is in a non-energized state. When the separation valve 60 is in the closed state, the flow of brake fluid in the main flow path 45 is blocked. When the solenoid is energized and the separation valve 60 is opened, the brake fluid can be circulated bidirectionally between the first flow path 45a and the second flow path 45b.

  In the hydraulic actuator 40, a master channel 61 and a regulator channel 62 communicating with the main channel 45 are formed. More specifically, the master channel 61 is connected to the first channel 45 a of the main channel 45, and the regulator channel 62 is connected to the second channel 45 b of the main channel 45. The master channel 61 is connected to a master pipe 37 that communicates with the master cylinder 32. The regulator channel 62 is connected to a regulator pipe 38 that communicates with the regulator 33.

  The master channel 61 has a master cut valve 64 in the middle. The master cut valve 64 is provided on the brake fluid supply path from the master cylinder 32 to each wheel cylinder 23. The master cut valve 64 has a solenoid and a spring that are ON / OFF-controlled, and the valve closing state is guaranteed by the electromagnetic force generated by the solenoid when supplied with a prescribed control current, so that the solenoid is in a non-energized state. It is a normally open electromagnetic control valve that is opened in some cases. The master cut valve 64 in the opened state can cause the brake fluid to flow in both directions between the master cylinder 32 and the first flow path 45 a of the main flow path 45. When a prescribed control current is applied to the solenoid and the master cut valve 64 is closed, the flow of brake fluid in the master flow path 61 is interrupted.

  A stroke simulator 69 is connected to the master channel 61 via a simulator cut valve 68 on the upstream side of the master cut valve 64. That is, the simulator cut valve 68 is provided in a flow path connecting the master cylinder 32 and the stroke simulator 69. The simulator cut valve 68 has a solenoid and a spring that are ON / OFF controlled, and the valve opening state is guaranteed by the electromagnetic force generated by the solenoid upon receipt of a specified control current, and the solenoid is in a non-energized state. It is a normally closed electromagnetic control valve that is closed in some cases. When the simulator cut valve 68 is closed, the flow of brake fluid between the master flow path 61 and the stroke simulator 69 is blocked. When the solenoid is energized and the simulator cut valve 68 is opened, the brake fluid can be circulated bidirectionally between the master cylinder 32 and the stroke simulator 69.

  The stroke simulator 69 includes a plurality of pistons and springs, and creates a reaction force corresponding to the depression force of the brake pedal 24 by the driver when the simulator cut valve 68 is opened. As the stroke simulator 69, in order to improve the feeling of brake operation by the driver, it is preferable to employ one having a multistage spring characteristic.

  The regulator flow path 62 has a regulator cut valve 65 in the middle. The regulator cut valve 65 is provided on the brake fluid supply path from the regulator 33 to each wheel cylinder 23. The regulator cut valve 65 also has a solenoid and a spring that are ON / OFF controlled, and the valve closing state is guaranteed by the electromagnetic force generated by the solenoid upon receipt of a specified control current, and the solenoid is in a non-energized state. It is a normally open electromagnetic control valve that is opened in some cases. The regulator cut valve 65 that has been opened can cause the brake fluid to flow in both directions between the regulator 33 and the second flow path 45 b of the main flow path 45. When the solenoid is energized and the regulator cut valve 65 is closed, the flow of brake fluid in the regulator flow path 62 is blocked.

  In the hydraulic actuator 40, an accumulator channel 63 is also formed in addition to the master channel 61 and the regulator channel 62. One end of the accumulator channel 63 is connected to the second channel 45 b of the main channel 45, and the other end is connected to an accumulator pipe 39 that communicates with the accumulator 35.

  The accumulator flow path 63 has a pressure-increasing linear control valve 66 in the middle. Further, the accumulator channel 63 and the second channel 45 b of the main channel 45 are connected to the reservoir channel 55 via the pressure-reducing linear control valve 67. The pressure-increasing linear control valve 66 and the pressure-decreasing linear control valve 67 each have a linear solenoid and a spring, and both are normally closed electromagnetic control valves that are closed when the solenoid is in a non-energized state. In the pressure-increasing linear control valve 66 and the pressure-decreasing linear control valve 67, the opening degree of the valve is adjusted in proportion to the current supplied to each solenoid.

  The pressure-increasing linear control valve 66 is provided as a common pressure-increasing control valve for each of the wheel cylinders 23 provided corresponding to each wheel. Similarly, the pressure-reducing linear control valve 67 is provided as a pressure-reducing control valve common to the wheel cylinders 23. That is, in this embodiment, the pressure-increasing linear control valve 66 and the pressure-reducing linear control valve 67 are a pair of common control valves that control the supply and discharge of the working fluid sent from the power hydraulic pressure source 30 to each wheel cylinder 23. It is provided as. Thus, if the pressure-increasing linear control valve 66 and the pressure-decreasing linear control valve 67 are made common to the wheel cylinders 23, it is preferable from the viewpoint of cost as compared to providing a linear control valve for each wheel cylinder 23.

  Here, the differential pressure between the inlet and outlet of the pressure-increasing linear control valve 66 corresponds to the differential pressure between the pressure of the brake fluid in the accumulator 35 and the pressure of the brake fluid in the main flow path 45, and the inlet / outlet of the pressure-reducing linear control valve 67. The pressure difference therebetween corresponds to the pressure difference between the brake fluid pressure in the main flow path 45 and the brake fluid pressure in the reservoir 34. Further, the electromagnetic driving force according to the power supplied to the linear solenoid of the pressure increasing linear control valve 66 and the pressure reducing linear control valve 67 is F1, the spring biasing force is F2, and the pressure increasing linear control valve 66 and the pressure reducing linear control valve are Assuming that the differential pressure acting force according to the differential pressure between the inlet / outlet of 67 is F3, the relationship of F1 + F3 = F2 is established. Therefore, the differential pressure between the inlet and outlet of the pressure-increasing linear control valve 66 and the pressure-reducing linear control valve 67 is controlled by continuously controlling the power supplied to the linear solenoids of the pressure-increasing linear control valve 66 and the pressure-reducing linear control valve 67. can do.

  In the brake control device 20, the power hydraulic pressure source 30 and the hydraulic actuator 40 are controlled by a brake ECU 70 as a control unit in the present embodiment. The brake ECU 70 is configured as a microprocessor including a CPU, and includes a ROM that stores various programs, a RAM that temporarily stores data, an input / output port, a communication port, and the like in addition to the CPU. The brake ECU 70 can communicate with a host hybrid ECU (not shown) and the like, and based on control signals from the hybrid ECU and signals from various sensors, the pump 36 of the power hydraulic pressure source 30 and the hydraulic pressure The electromagnetic control valves 51 to 54, 56 to 59, 60, and 64 to 68 constituting the actuator 40 are controlled.

  Further, a regulator pressure sensor 71, an accumulator pressure sensor 72, and a control pressure sensor 73 are connected to the brake ECU 70. The regulator pressure sensor 71 detects the pressure of the brake fluid in the regulator flow path 62 on the upstream side of the regulator cut valve 65, that is, the regulator pressure, and gives a signal indicating the detected value to the brake ECU 70. The accumulator pressure sensor 72 detects the pressure of the brake fluid in the accumulator flow path 63, that is, the accumulator pressure on the upstream side of the pressure increasing linear control valve 66, and gives a signal indicating the detected value to the brake ECU 70. The control pressure sensor 73 detects the pressure of the brake fluid in the first flow path 45a of the main flow path 45, and gives a signal indicating the detected value to the brake ECU 70. The detection values of the pressure sensors 71 to 73 are sequentially given to the brake ECU 70 every predetermined time, and are stored and held in a predetermined storage area of the brake ECU 70.

  When the separation valve 60 is opened and the first flow path 45 a and the second flow path 45 b of the main flow path 45 communicate with each other, the output value of the control pressure sensor 73 is the low pressure of the pressure-increasing linear control valve 66. This indicates the hydraulic pressure on the high pressure side of the pressure-reducing linear control valve 67 and the output value can be used to control the pressure-increasing linear control valve 66 and the pressure-reducing linear control valve 67. When the pressure-increasing linear control valve 66 and the pressure-decreasing linear control valve 67 are closed and the master cut valve 64 is opened, the output value of the control pressure sensor 73 indicates the master cylinder pressure. Further, the separation valve 60 is opened so that the first flow path 45a and the second flow path 45b of the main flow path 45 communicate with each other, and the ABS holding valves 51 to 54 are opened, while the ABS pressure reducing valves 56 are opened. When? 59 is closed, the output value of the control pressure sensor 73 indicates the working fluid pressure acting on each wheel cylinder 23, i.e., the wheel cylinder pressure.

  Further, the sensor connected to the brake ECU 70 includes a stroke sensor 25 provided on the brake pedal 24. The stroke sensor 25 detects a pedal stroke as an operation amount of the brake pedal 24 and gives a signal indicating the detected value to the brake ECU 70. The output value of the stroke sensor 25 is also sequentially given to the brake ECU 70 every predetermined time, and is stored and held in a predetermined storage area of the brake ECU 70. In the present embodiment, the stroke sensor 25 has two contact points, and can output two measured values to the brake ECU 70 as if they seemed to be two sensors.

  Further, a stop lamp switch is connected to the brake ECU 70. The stop lamp switch is turned on when the brake pedal 24 is depressed. As a result, the stop lamp is turned on. When the depression of the brake pedal 24 is released, the stop lamp switch is turned off and the stop lamp is turned off. A signal indicating the lighting state of the stop lamp switch is input from the stop lamp switch to the brake ECU 70 every predetermined time, and is stored and held in a predetermined storage area of the brake ECU 70.

  The brake control device 20 configured as described above can execute brake regeneration cooperative control. The brake control device 20 starts braking in response to a braking request. The braking request is generated when a braking force should be applied to the vehicle, for example, when the driver operates the brake pedal 24. In response to the braking request, the brake ECU 70 calculates a required braking force, and calculates a required hydraulic braking force that is a braking force to be generated by the brake control device 20 by subtracting the braking force due to regeneration from the required braking force. Here, the effective value of the braking force by regeneration is supplied from the hybrid ECU to the brake control device 20. Then, the brake ECU 70 calculates the target hydraulic pressure of each wheel cylinder 23FR to 23RL based on the calculated required hydraulic braking force. The brake ECU 70 determines the value of the control current supplied to the pressure-increasing linear control valve 66 and the pressure-decreasing linear control valve 67 based on the feedback control law so that the wheel cylinder pressure becomes the target hydraulic pressure.

  As a result, in the brake control device 20, the brake fluid is supplied from the power hydraulic pressure source 30 to the wheel cylinders 23 via the pressure-increasing linear control valve 66, and braking force is applied to the wheels. Further, brake fluid is discharged from each wheel cylinder 23 through the pressure-reducing linear control valve 67 as necessary, and the braking force applied to the wheel is adjusted. In the present embodiment, a wheel cylinder pressure control system is configured including the power hydraulic pressure source 30, the pressure-increasing linear control valve 66, the pressure-decreasing linear control valve 67, and the like. A so-called brake-by-wire braking force control is performed by the wheel cylinder pressure control system. The wheel cylinder pressure control system is provided in parallel to the brake fluid supply path from the master cylinder unit 27 to the wheel cylinder 23. The brake control device 20 according to the present embodiment can naturally control the braking force by the wheel cylinder pressure control system even when the required braking force is provided only by the hydraulic braking force without using the regenerative braking force. .

  When brake-by-wire braking force control is performed, the brake ECU 70 closes the regulator cut valve 65 so that the brake fluid delivered from the regulator 33 is not supplied to the wheel cylinder 23. Further, the brake ECU 70 closes the master cut valve 64 and opens the simulator cut valve 68. This is because the brake fluid sent from the master cylinder 32 in accordance with the operation of the brake pedal 24 by the driver is supplied not to the wheel cylinder 23 but to the stroke simulator 69. During the brake regeneration cooperative control, a differential pressure corresponding to the magnitude of the regenerative braking force acts between the upstream and downstream of the regulator cut valve 65 and the master cut valve 64. The brake ECU 70 opens the separation valve 60. Thereby, each wheel cylinder pressure is controlled to a common hydraulic pressure.

  FIG. 2 is a diagram showing the relationship between the brake pedal stroke and the hydraulic fluid pressure in the first embodiment of the present invention. In FIG. 2, the horizontal axis indicates the pedal stroke amount of the driver, and the vertical axis indicates the hydraulic fluid pressure generated according to the stroke. In FIG. 2, the relationship between the pedal stroke and the regulator pressure is indicated by a solid line, and the relationship between the pedal stroke and the control hydraulic pressure is indicated by a broken line. In this embodiment, the control hydraulic pressure is the upstream pressure of the wheel cylinder 23, that is, the hydraulic pressure in the main flow path 45, and is measured by the control pressure sensor 73.

  In the first embodiment, the power hydraulic pressure source 30 and the master cylinder unit 27 are selectively used as the hydraulic pressure source for controlling the wheel cylinder pressure. Specifically, the brake ECU 70 selects either the accumulator 35 or the regulator 33. The brake ECU 70 controls the wheel cylinder pressure by controlling the pressure-increasing linear control valve 66 when selecting the accumulator 35 as a hydraulic pressure source, and controls the regulator cut valve 65 when selecting the regulator 33. To control the wheel cylinder pressure. The brake ECU 70 may control the wheel cylinder pressure through both the pressure-increasing linear control valve 66 and the regulator cut valve 65 by using the accumulator 35 and the regulator 33 together as a hydraulic pressure source.

  In the first embodiment, the control hydraulic pressure by the pressure-increasing linear control valve 66 is controlled to be lower than the regulator pressure over the entire stroke range from the non-braking state to the state where the driver depresses the brake pedal 24 to the maximum. That is, the control hydraulic pressure is lower than the regulator pressure until the pedal stroke reaches the maximum stroke.

  As shown in FIG. 2, the regulator pressure does not rise until the stroke reaches the idle stroke A. When the stroke exceeds the idle stroke A, the regulator pressure increases in proportion to the stroke. On the other hand, the control hydraulic pressure increases with a relatively large gradient in the stroke when the brake pedal is initially depressed, and gradually increases as the stroke increases. Both the regulator pressure and the control hydraulic pressure increase monotonously with increasing stroke. In a range where the stroke is relatively small, the control hydraulic pressure follows the regulator pressure with a substantially constant differential pressure. As the stroke increases, the difference between the regulator pressure and the control hydraulic pressure increases. As described above, when the regenerative braking force is used, the brake ECU 70 reduces the hydraulic pressure corresponding to the regenerative braking force from the control hydraulic pressure shown in FIG. Therefore, the control hydraulic pressure shown in FIG. 2 is the control hydraulic pressure when the required braking force is satisfied only by the hydraulic braking force, that is, the maximum control hydraulic pressure corresponding to a certain stroke value.

  In this embodiment, the control hydraulic pressure has an idle stroke B larger than the idle stroke A of the regulator pressure, but is not limited to this. For example, the control hydraulic pressure may have an idle stroke equal to the idle stroke A of the regulator pressure, or may have an idle stroke smaller than the idle stroke A of the regulator pressure. The control hydraulic pressure may not have an idle stroke (ie, the idle stroke may be zero).

  By making the control hydraulic pressure lower than the regulator pressure in this way, it becomes possible to control the wheel cylinder pressure using the regulator 33 as a hydraulic pressure source. The brake ECU 70 normally controls the wheel cylinder pressure using the pressure-increasing linear control valve 66 and the pressure-decreasing linear control valve 67 as described above, but may also control the wheel cylinder pressure using the regulator cut valve 65. It becomes possible.

  The brake ECU 70 may determine whether or not to control the wheel cylinder upstream pressure with higher responsiveness than usual. What requires higher responsiveness than usual is, for example, during sudden braking or ABS control. ABS control is an example of control for stabilizing the behavior of the vehicle by suppressing the slip of each wheel with respect to the road surface. ABS control is a known control method for suppressing tire locking that occurs when braking is applied suddenly or on a slippery road surface. For example, the brake ECU 70 may determine that the control should be performed with high response when the target hydraulic pressure exceeds a predetermined value. Alternatively, when the differential pressure between the target hydraulic pressure and the actual hydraulic pressure exceeds a predetermined value, or when the increase rate of the target hydraulic pressure exceeds a predetermined value, it may be determined that the control should be performed with high response. .

  If the brake ECU 70 determines that the wheel cylinder upstream pressure should be controlled with high responsiveness, the brake ECU 70 stops the control of the pressure increasing linear control valve 66 and the pressure reducing linear control valve 67 and opens the regulator cut valve 65. As a result, the regulator 33 is connected to the wheel cylinder 23, and a high regulator pressure is introduced into the wheel cylinder 23. Therefore, the wheel cylinder pressure can be quickly increased. In this case, the brake ECU 70 may perform on / off duty control instead of simply opening the regulator cut valve 65, or may control the regulator cut valve 65 as a linear control valve.

  In this way, the hydraulic fluid pressure generated in the master cylinder with a hydraulic pressure booster by the driver's pedaling force can be efficiently utilized. For this reason, the control flow rate of the linear control valve can be reduced. Therefore, power consumption at the linear control valve can be reduced. A smaller linear control valve can also be employed.

  Also, as shown in FIG. 2, the differential pressure between the regulator pressure and the control hydraulic pressure increases as the stroke increases. Therefore, for example, a higher regulator pressure can be used as the stroke becomes larger as in sudden braking, which is more efficient and preferable.

  FIG. 3 is a diagram showing the relationship between the brake pedal stroke and the hydraulic fluid pressure in the second embodiment of the present invention. The second embodiment is the same as the first embodiment except that the control hydraulic pressure is made higher than the regulator pressure in a stroke smaller than the predetermined stroke. In the following description, description of the same points as in the first embodiment will be omitted as appropriate.

  In the second embodiment, as shown in FIG. 3, from the non-braking state to the switching stroke C, the control hydraulic pressure is set higher than the regulator pressure. Further, in the stroke exceeding the switching stroke C, the control hydraulic pressure is made lower than the regulator pressure as in the first embodiment. That is, the control hydraulic pressure is set to be higher than the regulator pressure in the low stroke region (low hydraulic pressure region) with reference to the switching stroke C, and the control hydraulic pressure is lower than the regulator pressure in the high stroke region (high hydraulic pressure region). Is set.

  The regulator pressure increases in proportion to the stroke in the stroke range exceeding the idle stroke A as in the first embodiment. In the second embodiment, no idle stroke is set for the control hydraulic pressure. The control hydraulic pressure starts increasing at a relatively large gradient from the beginning of the depression of the brake pedal, and gradually increases as the stroke increases. Therefore, the regulator pressure and the control hydraulic pressure have an intersection in the switching stroke C. In the high stroke region exceeding the switching stroke C, the difference between the regulator pressure and the control hydraulic pressure increases as the stroke increases.

  The switching stroke C is set to a value larger than the idle stroke A. Therefore, the brake feeling in the low stroke region including the idle stroke can be adjusted more preferably. In the low stroke region, the brake feeling can be set to a desired feeling independently from the master cylinder with a hydraulic booster.

  Thus, by setting the control hydraulic pressure to be lower than the regulator pressure in the high stroke region, it becomes possible to control the wheel cylinder pressure using the regulator 33 as a hydraulic pressure source. The brake ECU 70 normally controls the wheel cylinder pressure using the pressure-increasing linear control valve 66 and the pressure-decreasing linear control valve 67 as described above. However, in the high stroke region, the brake ECU 70 uses the regulator cut valve 65 to control the wheel cylinder pressure. Can also be controlled.

  The brake ECU 70 may switch the hydraulic pressure source of the wheel cylinder upstream pressure in the ABS control between a low stroke region (low hydraulic pressure region) and a high stroke region (high hydraulic pressure region). In this case, the brake ECU 70 controls the wheel cylinder upstream pressure by the pressure-increasing linear control valve 66 using the accumulator 35 as a hydraulic pressure source in the low stroke region below the switching stroke C, and the regulator 33 in the high stroke region exceeding the switching stroke C. The wheel cylinder upstream pressure is controlled by the regulator cut valve 65 using the pressure as a hydraulic pressure source. The brake ECU 70 calculates a target value of the wheel cylinder upstream pressure based on the pedal stroke. The brake ECU 70 switches the above-described hydraulic pressure source according to the stroke at the time when the ABS control is started (that is, the magnitude relationship between the control hydraulic pressure and the regulator pressure). In this way, the pressure-increasing linear control valve 66 does not have to be used for ABS control in a high hydraulic pressure region, so the load on the pressure-increasing linear control valve 66 is reduced and durability can be improved. .

  20 brake control device, 23 wheel cylinder, 27 master cylinder unit, 31 hydraulic booster, 32 master cylinder, 33 regulator, 34 reservoir, 60 separation valve, 64 master cut valve, 65 regulator cut valve, 66 pressure increase linear control valve, 67 pressure-reducing linear control valve, 70 brake ECU, 71 regulator pressure sensor, 72 accumulator pressure sensor, 73 control pressure sensor.

Claims (4)

A plurality of wheel cylinders for applying a braking force to each of the plurality of wheels according to the hydraulic fluid pressure;
A power hydraulic pressure source for accumulating hydraulic fluid by supplying power;
A master cylinder that pressurizes the stored hydraulic fluid according to a predetermined relationship between the brake pedal stroke and the hydraulic fluid pressure, and the hydraulic fluid source is used as a high-pressure source to adjust the hydraulic fluid in accordance with the hydraulic fluid pressure of the master cylinder. A manual hydraulic pressure source including a regulator for regulating pressure;
A wheel that is provided in parallel to a hydraulic fluid flow path that connects the manual hydraulic pressure source and the plurality of wheel cylinders, and controls upstream pressure common to the plurality of wheel cylinders using the power hydraulic pressure source as a high pressure source. A cylinder pressure control system;
A controller that calculates the common upstream pressure in accordance with a stroke and controls the wheel cylinder pressure control system to generate the calculated upstream pressure;
The wheel cylinder pressure control system includes a first path for supplying hydraulic pressure from the power hydraulic pressure source to the wheel cylinder through a first control valve, and the common upstream pressure is controlled by the first control valve. And
The hydraulic fluid flow path connecting the manual hydraulic pressure source and the plurality of wheel cylinders includes a second path for supplying the hydraulic pressure of the regulator to the wheel cylinder through a second control valve,
The control unit controls the upstream pressure generated by the wheel cylinder pressure control system to be lower in at least a predetermined stroke range than the hydraulic pressure obtained according to the relationship between the stroke and the hydraulic pressure in the manual hydraulic pressure source. The stroke range is a stroke larger than a predetermined stroke,
The control unit controls the upstream pressure higher than the working hydraulic pressure in the manual hydraulic pressure source during an idle stroke of the manual hydraulic pressure source,
In the stroke range, the control unit is configured such that the target hydraulic pressure exceeds a predetermined value, the differential pressure between the target hydraulic pressure and the actual hydraulic pressure exceeds a predetermined value, or the increase rate of the target hydraulic pressure is a predetermined value. When the pressure exceeds the hydraulic pressure supply, the brake control device switches the hydraulic pressure supply from the first path to the hydraulic pressure supply from the second path. The control unit calculates the common upstream pressure according to the relationship between the working fluid pressure and the working fluid pressure that increases as the stroke increases and the rate of increase in the working fluid pressure decreases.
When the stroke is small, the upstream pressure of the wheel cylinder is higher than the hydraulic pressure in the manual hydraulic pressure source when the stroke is small. 2. The relationship according to claim 1, wherein the hydraulic fluid pressure linearly changes according to the stroke with an inclination set so that the upstream pressure of the wheel cylinder is lower than the hydraulic fluid pressure in the hydraulic pressure source. The brake control device described. A regulator cut valve provided in a hydraulic fluid flow path connecting the regulator and the plurality of wheel cylinders ;
A master cut valve provided in a hydraulic fluid flow path connecting the master cylinder and the plurality of wheel cylinders ,
The controller determines whether or not the upstream pressure should be controlled with higher responsiveness than normal, and when it is determined that the control should be performed with high responsiveness, the control of the wheel cylinder pressure control system is stopped. the brake control apparatus according to claim 1 or 2, characterized in that supplying hydraulic fluid to said wheel cylinder in a state of closing the master cut valve through the regulator cut valve. A regulator cut valve provided in a hydraulic fluid flow path connecting the regulator and the plurality of wheel cylinders ;
A master cut valve provided in a hydraulic fluid flow path connecting the master cylinder and the plurality of wheel cylinders ,
When the master cut valve is closed and the target value of the common upstream pressure during ABS control is smaller than a predetermined value, the control unit controls the upstream pressure by the wheel cylinder pressure control system, The brake control device according to claim 1 or 2 , wherein when the target value is greater than the predetermined value, the upstream pressure is controlled by controlling the regulator cut valve.

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