JP6111920B2 - Hydraulic brake device for vehicles - Google Patents

Description

  The present invention relates to a hydraulic brake device for a vehicle that applies a braking force to wheels using hydraulic pressure of hydraulic fluid.

  Conventionally, an example of this type of vehicle hydraulic brake device is described in Patent Document 1 below. This hydraulic brake device for a vehicle described in Patent Document 1 includes a master cylinder having a reaction force fluid chamber and a drive fluid chamber, and an electric hydraulic pressure source that operates in response to a brake operation of a brake pedal. Using the four control valves (two-position solenoid valves) provided in the communication path between the hydraulic pressure source and the reaction force fluid chamber and the drive fluid chamber in the master cylinder, the fluid pressure and drive fluid in the reaction force fluid chamber It is comprised so that the hydraulic pressure of a chamber may be adjusted separately. In this case, as the four control valves, the first control valve provided in the first communication path between the electric hydraulic pressure source and the reaction force hydraulic chamber, and the electric hydraulic pressure source and the driving hydraulic chamber are provided. A second control valve provided in the second communication path, a third control valve provided in a third communication path between the reaction force liquid chamber and the reservoir, and a fourth communication between the drive liquid chamber and the reservoir. A fourth control valve provided in the path is used.

JP 2012-20707 A

  By the way, in the hydraulic brake device for a vehicle having the above-described configuration, the reaction force fluid chamber is obtained by variably controlling the valve opening degree of the third control valve at the start of the brake operation of the brake pedal and discharging part of the hydraulic fluid to the reservoir. The fluid pressure is adjusted. However, in the case of such control that discharges a part of the hydraulic fluid to the reservoir, there is room for improvement in energy saving because the energy consumed by the electric hydraulic pressure source increases.

  Accordingly, the present invention has been made in view of the above points, and one of the objects thereof is to reduce energy consumption in an electric hydraulic pressure source for supplying hydraulic fluid in a vehicle hydraulic brake device. It is to provide an effective technique for achieving this.

  In order to achieve this object, a hydraulic brake device for a vehicle according to the present invention is a device that is mounted on a vehicle to apply a braking force to a wheel using the hydraulic pressure of hydraulic fluid, and includes a master cylinder, A reservoir, an electric hydraulic pressure source, a first control valve, a second control valve, a third control valve, a fourth control valve, and a control unit are included. The master cylinder has a driving fluid chamber for driving a master piston for applying a braking force to the wheels by the hydraulic pressure of the hydraulic fluid in the master cylinder body and a reaction force corresponding to the brake operation of the brake pedal. A reaction force liquid chamber generated by pressure. The reservoir functions to store hydraulic fluid. The electric hydraulic pressure source operates in accordance with the brake operation of the brake pedal and pressurizes and discharges the hydraulic fluid stored in the reservoir by the electric pump. The first control valve is provided on the first supply path connecting the electric hydraulic pressure source and the reaction force liquid chamber so as to be able to be opened and closed. The second control valve is provided in a second supply path that connects the electric hydraulic pressure source and the driving fluid chamber so as to be able to be opened and closed. The third control valve is provided on the first discharge path connecting the reservoir and the reaction force liquid chamber so as to be openable and closable. The fourth control valve is provided on the second discharge path connecting the reservoir and the driving fluid chamber so as to be able to be opened and closed. It is also possible to add a separate control valve to each of the two supply paths and the two discharge paths.

  The control unit functions to control each of the electric hydraulic pressure source, the first control valve, the second control valve, the third control valve, and the fourth control valve in accordance with the brake operation of the brake pedal. In particular, this control unit executes the brake operation start time control mode when the brake pedal starts to be operated. In this brake operation start time control mode, the control unit outputs a closing instruction signal to the third control valve until the predetermined switching condition is satisfied in a state in which the first control valve and the second control valve are opened and driven. The valve opening degree of the fourth control valve is variably controlled based on the fluid pressure in the fluid chamber. Thereafter, the control unit switches from the brake operation start time control mode to the normal control mode when a predetermined switching condition is satisfied. In the normal control mode, the control unit variably controls the opening degree of the third control valve based on the hydraulic pressure of the reaction force liquid chamber in a state in which the first control valve and the second control valve are opened, and the driving fluid The valve opening degree of the fourth control valve is variably controlled based on the fluid pressure in the chamber.

  According to the vehicle hydraulic brake device having the above-described configuration, the reaction force fluid chamber is obtained by forcibly closing the third control valve by the close instruction signal at the start of the brake operation of the brake pedal or by maintaining the closed state. From the working fluid to the reservoir. As a result, it is possible to reduce the required discharge amount (pump rotation speed) of the electric pump by suppressing the amount of excess hydraulic fluid discharged to the reservoir, thereby reducing energy consumption in the electric hydraulic pressure source. Can be achieved. Further, when the third control valve is closed when the brake operation of the brake pedal is started, the working fluid in the reaction force fluid chamber is supplied toward the drive fluid chamber. Therefore, the rising of the hydraulic pressure in the driving fluid chamber is improved, and the braking force required for the wheels can be quickly achieved.

  In the vehicle hydraulic brake device having the above-described configuration, the control unit, in the brake operation start time control mode, generates a difference between the two paths of the first control valve in the first supply path when the electric hydraulic pressure source is activated. It is preferable to determine that a predetermined switching condition is satisfied when the hydraulic pressure in the driving fluid chamber reaches the hydraulic pressure in the reaction force fluid chamber due to the pressure. Thus, switching from the brake operation start time control mode to the normal control mode can be set based on the relative relationship between the hydraulic pressure in the driving fluid chamber and the hydraulic pressure in the reaction force fluid chamber.

  In the vehicle hydraulic brake device having the above-described configuration, the control unit sets the target hydraulic pressure for generating the reaction force according to the brake operation of the brake pedal in the brake operation start control mode. It is preferable to determine that a predetermined switching condition is satisfied when the time is reached. Thereby, switching from the brake operation start time control mode to the normal control mode can be easily set based only on the hydraulic pressure of the reaction force liquid chamber.

  In the vehicle hydraulic brake device having the above-described configuration, the control unit establishes a predetermined switching condition when a preset set time elapses after the brake operation of the brake pedal is started in the brake operation start control mode. It is preferable to determine that it has been. Thereby, switching from the brake operation start time control mode to the normal control mode can be easily set using a preset set time.

  As described above, according to the present invention, in the vehicle hydraulic brake device, it is possible to reduce energy consumption in the electric hydraulic pressure source for supplying hydraulic fluid.

1 is a diagram schematically showing a configuration of a vehicle hydraulic brake device 100 according to an embodiment of the present invention. It is a figure which shows a part of hydraulic brake device 100 for vehicles in FIG. 1 in a non-operation state. 3 is a diagram showing a brake operation state when the electrical system is normal in the vehicle hydraulic brake device 100 in FIG. 2 and a brake operation start control mode is being executed by the brake ECU 50. FIG. FIG. 3 is a diagram showing a brake operating state when the electrical system is normal in the vehicle hydraulic brake device 100 in FIG. 2 and a normal control mode is being executed by a brake ECU 50. It is a figure for demonstrating the switching timing from a brake operation start time control mode to normal control mode. It is a figure which shows a brake operating state when an electric system is abnormal in the hydraulic brake device for vehicles 100 in FIG. It is a figure which shows a part of vehicle hydraulic brake device 200 which concerns on the example of a change of the hydraulic brake device for vehicles in FIG. 2 in a non-operation state.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a vehicle hydraulic brake device (hereinafter also simply referred to as “brake device”) 100 according to an embodiment of the present invention. The brake device 100 is mounted on a vehicle so as to apply a braking force to a wheel by using hydraulic pressure of hydraulic fluid, and includes a brake pedal 10, a master cylinder 20, and four wheel cylinders FL assigned to the wheel. , FR, RL, RR, brake hydraulic pressure control actuator 30, hydraulic pressure control circuit 40, and brake ECU 50.

  The brake pedal 10 is a brake operation member applied to a driver's brake operation (depression operation), and the master cylinder 20 is operated based on the brake operation of the brake pedal 10. The master cylinder 20 includes a master cylinder body composed of a first cylinder body 21 and a second cylinder body 22, and has a plurality of components in the master cylinder body. This master cylinder body corresponds to the “master cylinder” of the present invention. Specifically, the first cylinder body 21 of the master cylinder 20 is formed in a long cylindrical shape having a cylinder inner hole 21a, and the input piston 23 assembled in the cylinder inner hole 21a is used as a brake of the brake pedal 10. It is configured to be pressed by an operation and drive in the first direction D1. The operation amount of the brake pedal 10 (hereinafter also referred to as “actuation amount”) is detected by both the stroke sensor S1 and the pedal force sensor S2, and detection signals of the stroke sensor S1 and the pedal force sensor S2 are transmitted to the brake ECU 50. Instead of the brake pedal 10, a brake operation member such as a brake lever may be employed.

  A reaction force liquid chamber (also referred to as “reaction force chamber”) C <b> 1 defined by the input piston 23 is provided in the cylinder inner hole 21 a of the first cylinder body 21. The reaction force fluid chamber C1 is connected to a master reservoir Rm in which hydraulic fluid (also referred to as “brake fluid”) is stored and a hydraulic pressure control circuit 40. The hydraulic fluid is connected to each connection destination. Distribution is possible. The reaction force fluid chamber C1 functions to generate a reaction force according to the brake operation of the brake pedal 10 by the hydraulic pressure of the hydraulic fluid. This reaction force liquid chamber C1 corresponds to the “reaction force liquid chamber” of the present invention. The input piston 23 includes a small diameter portion 23 a that protrudes from the cylinder inner hole 21 a of the first cylinder body 21 to the cylinder inner hole 22 a of the second cylinder body 22.

  The master cylinder 20 includes a second cylinder body 22 that is coaxially connected to the first cylinder body 21. The second cylinder body 22 has a long cylindrical shape having a cylinder inner hole 22a, and a pair of master pistons 24 and 25 and a pair of springs 26 and 27 are assembled to the cylinder inner hole 22a. In this case, the first master piston 24 and the second master piston 25 are arranged in this order from the input piston 23 side in the cylinder axial direction of the master cylinder 20, and the spring 26 elastically moves the first master piston 24 in the second direction D2. The spring 27 elastically biases the second master piston 25 in the second direction D2. The cylinder bore 22a of the second cylinder body 22 is connected to each of the master reservoir Rm, the brake hydraulic pressure control actuator 30 and the hydraulic pressure control circuit 40, and hydraulic fluid flows between these connection destinations. It is possible.

  A driving fluid chamber (also referred to as a “servo chamber”) C2, a pressure chamber C3, and a pressure chamber C4 are provided in the cylinder inner hole 22a of the second cylinder body 22. The driving fluid chamber C <b> 2 is partitioned by the small diameter portion 23 a of the input piston 23 and the first master piston 24. The small diameter portion 23a of the input piston 23 can be engaged and disengaged with respect to the first master piston 24 by driving in the cylinder axial direction, and is in the initial position (also referred to as “return position”) shown in FIG. Is arranged at a predetermined distance L from the first master piston 24 in the cylinder axial direction of the master cylinder 20. The first master piston 24 resists the elastic biasing force of the spring 26 in the second direction D2 by the pressing force of the small diameter portion 23a of the input piston 23 in the first direction D1 or by the hydraulic pressure of the hydraulic fluid in the driving fluid chamber C2. Driven. This driving liquid chamber C2 corresponds to the “driving liquid chamber” of the present invention. The pressure chamber C <b> 3 is partitioned by the first master piston 24 and the second master piston 25. The pressure chamber C4 is formed on the opposite side of the pressure chamber C3 with the second master piston 25 interposed therebetween. The second master piston 25 is driven against the elastic biasing force of the spring 27 in the second direction D2 by the elastic biasing force of the spring 26 in the first direction D1 or by the hydraulic pressure of the hydraulic fluid in the pressure chamber C3.

  The reaction force fluid chamber C1 and the driving fluid chamber C2 are connected to the fluid pressure control circuit 40, respectively. On the other hand, each of the pressure chamber C3 and the pressure chamber C4 is connected to the brake fluid pressure control actuator 30. The reaction force liquid chamber C1 and the pressure chambers C3 and C4 communicate with the master reservoir Rm when the pistons 23, 24, and 25 are at the initial positions in FIG. On the other hand, the reaction force liquid chamber C1 and the pressure chambers C3 and C4 are disconnected from the master reservoir Rm when the pistons 23, 24, and 25 move in the first direction D1 from the initial position in FIG.

  The hydraulic pressure in the pressure chamber C3 increases when the first master piston 24 moves in the first direction D1, and the hydraulic pressure in the pressure chamber C4 increases when the second master piston 25 moves in the first direction D1. . In this case, the hydraulic pressure in the pressure chamber C3 and the hydraulic pressure in the pressure chamber C4 are transmitted to each of the wheel cylinders FL, FR, RL, RR via the brake hydraulic pressure control actuator 30, and braking force is applied to the wheels. The In this case, in particular, the driving fluid chamber C2 functions to drive the master pistons 24 and 25 that apply braking force to the wheels by the hydraulic pressure of the working fluid.

  Note that the configuration of the master cylinder 20 other than those described above is referred to the master cylinder of the vehicle hydraulic brake device described in FIG. 1 of Japanese Patent Application Laid-Open No. 2012-20707. Further, the configuration of the wheel cylinders FL, FR, RL, RR and the configuration of the brake hydraulic pressure control actuator 30 for driving the wheel cylinder are described in FIG. 1 of Japanese Patent Application Laid-Open No. 2012-20707. Reference is made to wheel cylinder and brake fluid pressure control actuator configurations.

  As shown in FIGS. 1 and 2, the hydraulic pressure control circuit 40 includes an atmospheric pressure reservoir Ra, an electric hydraulic pressure source 41, a suction path 42, a discharge path 43, a first supply path 44, a first discharge path 45, A second supply path 46, a second discharge path 47, a circulation path 48, a plurality of valves (valves) V1 to V7, and pressure sensors S3 and S4 are included.

  The atmospheric pressure reservoir Ra functions to store hydraulic fluid. The electric hydraulic pressure source 41 includes an electric pump P that is driven by the electric motor M in its operating state. The electric pump P draws hydraulic fluid (brake fluid) stored in the atmospheric pressure reservoir Ra from the suction passage 42. Inhaled, pressurized and discharged into the discharge passage 43. In addition to the electric pump P, pressure accumulation means such as an accumulator can be used as the electric hydraulic pressure source 41. The electric hydraulic pressure source 41 and the atmospheric pressure reservoir Ra mentioned here correspond to the “electric hydraulic pressure source” and the “reservoir” of the present invention, respectively.

  The first supply path 44 communicates with the discharge path 43 and connects the electric hydraulic pressure source 41 and the reaction force liquid chamber C1. In particular, in the first supply path 44, a path cross-sectional area (also referred to as “flow path diameter”) is set so that a differential pressure is generated between the upstream side and the downstream side of the first control valve V1 described later. Yes. Specifically, the cross-sectional area of the first supply path 44 on the reaction force fluid chamber C1 side of the first control valve V1 is smaller than the cross-sectional area of the electric hydraulic pressure source 41 side of the first control valve V1. It is configured as follows. The first discharge path 45 is a path that connects the atmospheric pressure reservoir Ra and the reaction force liquid chamber C <b> 1 by connecting the connection portion X <b> 1 on the first supply path 44 and the circulation path 48. On the other hand, the second supply path 46 communicates with the discharge path 43 and is a path for connecting the electric hydraulic pressure source 41 and the driving fluid chamber C2. The second discharge path 47 is a path that connects the atmospheric pressure reservoir Ra and the driving fluid chamber C2 by connecting the connection portion X2 on the second supply path 46 and the circulation path 48. The circulation path 48 is a path for connecting the first discharge path 45 and the second discharge path 47 to the atmospheric pressure reservoir Ra.

  The pressure sensor S3 is a sensor that detects the pressure (hydraulic fluid pressure) in the first supply path 44, and the detection information is transmitted to the brake ECU 50. The pressure sensor S4 is a sensor that detects the pressure (hydraulic fluid pressure) in the second supply path 46, and the detection information is transmitted to the brake ECU 50.

  The first control valve V1 is a normally open and electromagnetic on-off valve (on / off valve (two-position electromagnetic valve)), and is upstream of the connecting portion X1 (on the discharge path 43 side) in the first supply path 44. It is provided so that opening and closing control is possible. The second control valve V2 is a normally open and electromagnetic on-off valve (on / off valve (two-position electromagnetic valve)), and is upstream of the connection portion X2 (on the discharge path 43 side) in the second supply path 46. It is provided so that opening and closing control is possible. The first control valve V1 and the second control valve V2 correspond to the “first control valve” and the “second control valve” of the present invention, respectively. The main check valve V3 is provided in the discharge path 43 of the electric hydraulic pressure source 41, and functions to restrict the flow of hydraulic fluid to the electric hydraulic pressure source 41 side. The first check valve V4 is arranged in parallel to the first control valve V1 in the first supply path 44, and fulfills a function of regulating the flow of hydraulic fluid to the downstream side (connecting part X1 side). The second check valve V5 is arranged in parallel to the first control valve V2 in the second supply path 46, and fulfills the function of regulating the flow of hydraulic fluid to the downstream side (connecting part X2 side).

  The third control valve V6 is a normally closed electromagnetic linear control valve, and is provided in the first discharge path 45 so that the valve opening degree can be variably controlled. The third control valve V6 functions to control the hydraulic pressure of the hydraulic fluid supplied from the electric hydraulic pressure source 41 to the reaction force fluid chamber C1 through the first supply path 44 in accordance with the operation amount of the brake pedal 10. . That is, the valve opening degree of the third control valve V6 is variably controlled so that the fluid pressure in the reaction force fluid chamber C1 (detected value of the pressure sensor S3) becomes a target value corresponding to the operation amount of the brake pedal 10. The fourth control valve V7 is a normally closed electromagnetic linear control valve, and is provided in the second discharge path 47 so that the valve opening degree can be variably controlled. The fourth control valve V7 functions to control the hydraulic pressure of the hydraulic fluid supplied from the electric hydraulic pressure source 41 to the driving fluid chamber C2 through the second supply path 46 according to the operation amount of the brake pedal 10. That is, the valve opening degree of the fourth control valve V7 is variably controlled so that the hydraulic pressure in the driving fluid chamber C2 (detected value of the pressure sensor S4) becomes a target value corresponding to the operation amount of the brake pedal 10. In this case, typically, the target value of the hydraulic pressure in the driving fluid chamber C2 is set to exceed the target value of the hydraulic pressure in the reaction force fluid chamber C1. The third control valve V6 and the fourth control valve V7 here correspond to the “third control valve” and the “fourth control valve” of the present invention, respectively.

  In the brake device 100 having the above-described configuration, the brake ECU 50 is configured to operate the electric hydraulic pressure source of the hydraulic pressure control circuit 40 according to the brake operation of the brake pedal 10, specifically based on detection information from the sensors S1 to S4. 41, each operation of the first control valve V1, the second control valve V2, the third control valve V6, and the fourth control valve V7 is controlled. The brake ECU 50 corresponds to the “control unit” of the present invention.

  In the following, when the electrical system is normal, typically when the electrical equipment of the hydraulic control circuit 40 and the brake ECU 50 are not broken, and when the electrical system is abnormal, the electrical system typically The operation of the hydraulic pressure control circuit 40 will be described with reference to FIGS. 3 to 6 in the case where the electrical equipment of the hydraulic pressure control circuit 40 and the brake ECU 50 break down due to failure. Among these drawings, particularly in FIGS. 3, 4 and 6, the path through which the hydraulic pressure of the hydraulic fluid is constantly acting is indicated by a thick solid line.

  When the electrical system is normal, the brake ECU 50 activates the electric hydraulic pressure source 41 by detecting the brake operation of the brake pedal 10. That is, the electric hydraulic pressure source 41 is operated in accordance with the brake operation of the brake pedal 10 and the hydraulic fluid stored in the atmospheric pressure reservoir Ra is pressurized and discharged by the electric pump P. The present embodiment is characterized in that the brake ECU 50 executes the brake operation start time control mode shown in FIG. 3 at the start of the brake operation (at the beginning of the brake operation). In this brake operation start time control mode, the brake ECU 50 outputs a close instruction signal to the third control valve V6 until a predetermined switching condition is satisfied with the first control valve V1 and the second control valve V2 opened. In addition, the valve opening degree of the fourth control valve V7 is variably controlled based on the hydraulic pressure in the driving fluid chamber C2 (substantially detection information of the pressure sensor S4).

  According to this brake operation start time control mode, the third control valve V6 that is open in the initial state is forcibly closed by the close instruction signal, thereby causing the hydraulic fluid from the reaction force liquid chamber C1 to the atmospheric pressure reservoir Ra. Is blocked. As a result, the required discharge amount (pump) of the electric pump P is suppressed by suppressing the amount of excess hydraulic fluid discharged from the electric hydraulic pressure source 41 using the electric pump P to the atmospheric pressure reservoir Ra through the first discharge path 45. The number of revolutions) can be reduced, and thus the energy consumption in the electric hydraulic pressure source 41 can be reduced. Further, the third control valve V6 is forcibly closed, so that the working fluid in the reaction force fluid chamber C1 is supplied toward the driving fluid chamber C2. Therefore, the rising of the hydraulic pressure in the driving fluid chamber is improved, and the braking force required for the wheels can be quickly achieved. At this time, there is a predetermined time lag for the electric hydraulic pressure source 41 to operate and the driving fluid chamber C2 to rise to a desired hydraulic pressure, so that the brake pedal 10 is particularly suddenly operated by the driver. Sometimes it is difficult to obtain the desired braking force. Therefore, as in the present embodiment, the control for forcibly closing the third control valve V6 in the above-described brake operation start time control is particularly effective during the sudden brake operation.

  Thereafter, the brake ECU 50 switches from the aforementioned brake operation start time control mode to the normal control mode shown in FIG. 4 when a predetermined switching condition is satisfied. In this normal control mode, the brake ECU 50 performs the first operation based on the fluid pressure in the reaction force fluid chamber C1 (substantially detected information from the pressure sensor S3) with the first control valve V1 and the second control valve V2 opened. 3 The valve opening of the control valve V6 is variably controlled, and the valve opening of the fourth control valve V7 is variably controlled based on the hydraulic pressure in the driving fluid chamber C2 (substantially the detection information of the pressure sensor S4). In this case, the fluid pressure in the reaction force fluid chamber C1 and the fluid pressure in the drive fluid chamber C2 are adjusted separately. As a result, the reaction force fluid chamber C1 and the driving fluid chamber C2 are adjusted to the target fluid pressure corresponding to the operation amount of the brake pedal 10, and appropriate reaction force and braking force are obtained.

  Here, FIG. 5 is referred to for the switching timing from the brake operation start time control mode to the normal control mode, that is, the end of the brake operation start time control mode. As shown in FIG. 5, in the brake operation start time control mode, the third control valve V6 is set at the time ta when it is determined that the brake operation of the brake pedal 10 is started based on the detection information of the stroke sensor S1 and the pedal force sensor S2. A closing instruction signal is output. Accordingly, the hydraulic pressure in the reaction force chamber C1 increases with the passage of time from this time point ta. At this time, the liquid in the second supply path 46 is activated by the operation of the electric hydraulic pressure source 41 by the differential pressure structure between the upstream side and the downstream side of the first control valve V1 in the first supply path 44 as described above. Until the pressure increases, the fluid pressure P1 in the reaction fluid chamber C1 exceeds the fluid pressure P2 in the drive fluid chamber C2. Furthermore, the hydraulic pressure P2 in the driving fluid chamber C2 rises until reaching the fluid pressure P1 in the reaction force fluid chamber C1 at time tb, and then the reaction force fluid chamber is further generated by the differential pressure generated between the two paths of the first control valve V1. It rises until it exceeds the hydraulic pressure P1 of C1. In the present embodiment, the brake ECU 50 determines that the above-mentioned “predetermined” when the hydraulic pressure P2 of the driving fluid chamber C2 reaches the hydraulic pressure P1 of the reaction fluid chamber C1 based on the detection information of both the pressure sensors S3 and S4. It can be determined that the “switching condition” is satisfied.

  Regarding this determination, instead of using the detection information of both the pressure sensors S3 and S4, a form using only the detection information of the pressure sensor S3 can be adopted. Specifically, when the hydraulic pressure in the reaction force fluid chamber C1 reaches a target hydraulic pressure for generating a reaction force according to the brake operation of the brake pedal 10, it is determined that a predetermined switching condition is satisfied. it can. Thereby, switching from the brake operation start time control mode to the normal control mode can be easily set based only on the hydraulic pressure of the reaction force liquid chamber C1. As a further modification, a predetermined switching condition is used when a preset time elapses from the start of the brake operation of the brake pedal 10 by means such as a timer without using detection information of the pressure sensors S3, S4, etc. It can also be determined that Thereby, switching from the brake operation start time control mode to the normal control mode can be easily set using a preset set time.

  As shown in FIG. 6, when the electrical system is abnormal, typically, when the electrical equipment of the hydraulic control circuit 40 and the brake ECU 50 are broken due to the failure of the electrical system, the instruction signal to each control valve is By not outputting, both the first control valve V1 and the second control valve V2 are opened, and the third control valve V6 and the fourth control valve V7 are both closed. As a result, in the state where the flow of the hydraulic fluid from the first supply path 44 and the second supply path 46 to the discharge path 43 is regulated by the main check valve V3, the reaction force liquid chamber C1 has the first supply path 44 and the first supply path 44. 2 It communicates with the driving fluid chamber C2 through the supply path 46. Therefore, when the electric system is abnormal, the hydraulic fluid in the reaction force liquid chamber C1 is delayed to the driving fluid chamber C2 through the first supply path 44 and the second supply path 46 according to the operation amount of the brake pedal 10. The first master piston 24 and the second master piston 25 operate without any invalid stroke. For this reason, it becomes possible for the master cylinder 20 to operate properly to generate a desired braking force.

  In the above-described embodiment, when regenerative braking is required during normal braking operation, the brake ECU 50 controls the driving fluid from the electric hydraulic pressure source 41 through the second supply path 46 by controlling to close the second control valve V2. The hydraulic fluid is prevented from being supplied to the chamber C2. In this case, it is possible to set a state in which a braking force is obtained by a regenerative braking device (not shown) and a reaction force corresponding to a brake operation is obtained by the master cylinder 20 but a braking force cannot be obtained. is there. As a result, it is possible to obtain a brake operation that ensures high regeneration efficiency.

  The present invention is not limited to the above exemplary embodiment, and various applications and modifications are possible. For example, each of the following embodiments to which the above embodiment is applied can be implemented.

  In the above embodiment, when the hydraulic pressure P2 of the driving fluid chamber C2 reaches the hydraulic pressure P1 of the reaction force fluid chamber C1 as the switching timing from the brake operation start control mode to the normal control mode, the reaction force fluid chamber C1. In the present invention, three cases have been described in which the preset hydraulic pressure reaches the target hydraulic pressure and a preset set time has elapsed from the start of the brake operation. However, in the present invention, other timings are set as necessary. You can also. For example, when the hydraulic pressure P2 in the driving fluid chamber C2 reaches the target hydraulic pressure, or when the differential pressure between the hydraulic pressure P2 in the driving fluid chamber C2 and the hydraulic pressure P1 in the reaction fluid chamber C1 reaches the target value. Switching from the brake operation start control mode to the normal control mode can be executed.

  In the above-described embodiment, the case where one component of the hydraulic control circuit 40 includes one electric hydraulic pressure source 41 and four control valves V1, V2, V6, and V7 has been described. Then, the number and arrangement of the electric hydraulic pressure source and the control valve can be appropriately changed as necessary. For example, the brake device 200 including the hydraulic pressure control circuit 140 to which FIG. 7 is referred can be employed.

  In the hydraulic control circuit 140 shown in FIG. 7, instead of one normally closed linear control valve (third control valve V6) of the hydraulic control circuit 40, one normally open linear control valve V6a and one A normally closed control valve (on / off valve (two-position electromagnetic valve)) V6b is connected in series, and one normally closed linear control valve (fourth control) of the hydraulic pressure control circuit 40 is used. Instead of the valve V7), one normally open type linear control valve V7a and one normally closed type control valve (on / off valve (two-position solenoid valve)) V7b are connected in series. Yes. In this configuration, in the aforementioned brake operation start control, both the linear control valve V6a and the linear control valve V7a are controlled to be closed by the close instruction signal, and both the control valve V6b and the control valve V7b are open by the open instruction signal. Controlled. In the subsequent normal control, both the valve opening degrees of the linear control valve V6a and the linear control valve V7a are variably controlled while the control valve V6b and the control valve V7b are both in the open state. On the other hand, when the electric system fails, the instruction signal is not output, so that both the linear control valve V6a and the linear control valve V7a are opened, and both the fail-safe control valve V6b and the control valve V7b are closed. According to the hydraulic pressure control circuit 140, the hydraulic pressure control can be optimized by using the normally open linear control valves V6a and V7a which are superior in controllability to the normally closed linear control valve. On the other hand, in the above-described hydraulic pressure control circuit 40, the cost can be reduced by limiting the number of electromagnetic valves provided in the first discharge path 45 to two of the third control valve V6 and the fourth control valve V7. .

  DESCRIPTION OF SYMBOLS 100, 200 ... Hydraulic brake device for vehicles, 10 ... Brake pedal (brake operation member), 20 ... Master cylinder, 21 ... 1st cylinder body, 21a ... Cylinder bore, 22 ... 2nd cylinder body, 22a ... In cylinder Hole, 23 ... Input piston, 23a ... Small diameter portion, 24 ... First master piston, 25 ... Second master piston, 26, 27 ... Spring, 30 ... Brake fluid pressure control actuator, C1 ... Reaction force fluid chamber, C2 ... Drive fluid chamber, C3 ... pressure chamber, 40, 140 ... hydraulic pressure control circuit, 41 ... electric hydraulic pressure source, 42 ... suction path, 43 ... discharge path, 44 ... first supply path, 45 ... first discharge path, 46 ... Second supply path, 47 ... Second discharge path, 48 ... Reflux path, 50 ... Brake ECU (control unit) FL, FR, RL, RR ... Wheel cylinder, Ra ... Atmospheric pressure reservoir, Rm Master reservoir, V1 ... first control valve, V2 ... second control valve, V3 ... main check valve, V4 ... first check valve, V5 ... second check valve, V6 ... third control valve, V7 ... first 4 control valve, S1 ... stroke sensor, S2 ... pedaling force sensor, S3, S4 ... pressure sensor

Claims (4)

A vehicle hydraulic brake device mounted on a vehicle,
In the master cylinder body, a driving fluid chamber for driving the master piston for applying a braking force to the wheels by the hydraulic pressure of the hydraulic fluid and a reaction force corresponding to the brake operation of the brake pedal are generated by the hydraulic pressure of the hydraulic fluid. A master cylinder having a reaction force liquid chamber,
A reservoir for storing hydraulic fluid;
An electric hydraulic pressure source that operates in accordance with a brake operation of the brake pedal and pressurizes and discharges the hydraulic fluid stored in the reservoir by an electric pump;
A first control valve provided in a first supply path connecting the electric hydraulic pressure source and the reaction force liquid chamber so as to be capable of opening and closing;
A second control valve provided in a second supply path connecting the electric hydraulic pressure source and the driving fluid chamber so as to be capable of opening and closing;
A third control valve provided in a first discharge path connecting the reservoir and the reaction force liquid chamber so as to be capable of opening and closing;
A fourth control valve provided in a second discharge path connecting the reservoir and the driving fluid chamber so as to be capable of opening and closing;
A controller that controls each of the electric hydraulic pressure source, the first control valve, the second control valve, the third control valve, and the fourth control valve in accordance with a brake operation of the brake pedal. ,
The controller is
When a brake operation of the brake pedal is started, a closing instruction signal is output to the third control valve until a predetermined switching condition is satisfied with the first control valve and the second control valve being opened, and the drive Executing a brake operation start time control mode for variably controlling the opening degree of the fourth control valve based on the fluid pressure in the fluid chamber;
When the predetermined switching condition is satisfied, the first control valve and the second control valve are controlled to be opened from the brake operation start time control mode based on the fluid pressure in the reaction force fluid chamber. 3. A vehicular hydraulic brake device that variably controls the valve opening of the three control valves and switches to a normal control mode in which the valve opening of the fourth control valve is variably controlled based on the hydraulic pressure of the driving fluid chamber. The hydraulic brake device for a vehicle according to claim 1,
In the control mode at the time of starting the brake operation, the control unit is configured to drive the driving fluid chamber by a differential pressure generated between both side paths of the first control valve in the first supply path in a state where the electric hydraulic pressure source is operated. The vehicle hydraulic brake device determines that the predetermined switching condition is satisfied when the hydraulic pressure reaches the hydraulic pressure of the reaction force hydraulic chamber. The hydraulic brake device for a vehicle according to claim 1,
In the brake operation start time control mode, the control unit performs the predetermined operation when the hydraulic pressure of the reaction force liquid chamber reaches a target hydraulic pressure for generating a reaction force according to a brake operation of the brake pedal. A vehicle hydraulic brake device that determines that the switching condition is satisfied. The hydraulic brake device for a vehicle according to claim 1,
The control unit determines that the predetermined switching condition is satisfied when a preset set time has elapsed after the brake operation of the brake pedal is started in the brake operation start control mode. Hydraulic brake device.

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