KR20220152641A - Braking System of Vehicle Capable of Regenerative Braking and Hydraulic Braking and Controlling Method Thereof - Google Patents

Abstract

Disclosed is a brake system of a vehicle that performs regenerative braking and hydraulic braking. According to one embodiment of the present disclosure, the brake system comprises: a master cylinder; a reaction disc; an electric booster unit including a motor piston disposed to pressurize at least a portion of the reaction disc and a screw shaft disposed to pressurize the motor piston and configured to pressurize the master cylinder by adjusting the displacement of the motor piston; a rod assembly including an operating rod disposed to adjust the displacement depending on the depression of a brake pedal of a driver and an elastic body having one end in contact with a portion of the operating rod and the other end in contact with at least a portion of the electric booster unit; and a control unit configured to control the electric booster unit and perform control to brake a vehicle using at least one of regenerative braking and hydraulic braking. Accordingly, the present invention can make a driver feel no sense of difference in depression.

Description

Brake system of vehicle performing regenerative braking and hydraulic braking and its control method

The present disclosure relates to a brake system of a vehicle that performs regenerative braking and hydraulic braking and a control method thereof.

The content described in this section simply provides background information for the present disclosure and does not constitute prior art.

Regenerative braking is a braking method in which a motor is driven as a generator using driving inertia of a vehicle and resistance generated by driving the motor is used as a braking force.

In the case of an HEV (Hybrid Electric Vehicle) vehicle, when braking the vehicle, as the regenerative braking unit and the hydraulic braking unit cooperate to brake (hereinafter referred to as 'coordinated braking'), the vehicle can supply a stable braking force.

The vehicle further includes an electric booster unit for boosting a driver's pedal effort. The electric booster unit uses the rotational torque of the electric motor provided in the electric booster unit to increase the force by which the operating rod presses the inside of the master cylinder. In addition, the electric booster unit is configured to provide a required pedal feel to the driver when forming a pedal feel. Specifically, the electric booster unit is configured such that an appropriate leg force corresponding to a pedal stroke is formed by pressing a reaction disc by the electric booster unit.

Meanwhile, when a vehicle equipped with a conventional cooperative braking function performs regenerative braking, hydraulic pressure is reduced by using electronic stability control (ESC) by a braking compensation amount according to regenerative braking. To this end, a conventional vehicle requires an ESC having specifications capable of cooperatively controlling regenerative braking and hydraulic braking. Specifically, since the ESC additionally requires a pressure reducing device such as an accumulator to reduce the hydraulic pressure, the specifications of the ESC increase. Accordingly, there is a problem of cost increase.

In addition, when regenerative braking is released during cooperative braking of a vehicle equipped with a conventional cooperative braking function, the amount of hydraulic oil in the brake system is increased by using the ESC to increase the braking force of hydraulic braking. In order to increase the amount of hydraulic oil in the brake system, a pump is operated to draw hydraulic oil from the master cylinder. As a result, the pressure formed inside the master cylinder is lowered, and the driver can feel the difference in pedal effort.

Therefore, the main object of the present disclosure is to reduce the regenerative braking force by receiving the regenerative braking stop signal and to eliminate the sense of incongruity of the step that occurs when the hydraulic braking force is increased by using an electric booster.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to an embodiment of the present disclosure, a brake system configured to perform cooperative braking in which regenerative braking and hydraulic braking are performed together in a braking situation of a vehicle, comprising: a master cylinder; a reaction disc having an elastic material arranged to pressurize the master cylinder; An electric booster unit including a motor piston disposed to pressurize at least a portion of the reaction disk and a screw shaft disposed to pressurize the motor piston, and configured to pressurize the master cylinder by adjusting the displacement of the motor piston. ); An operating rod disposed to adjust the displacement according to the driver's depression of the brake pedal of the vehicle, and an elastic body disposed such that one end is in contact with a portion of the operating rod and the other end is in contact with at least a portion of the electric booster unit. rod assembly; and a control unit configured to control the electric booster unit and perform control to brake the vehicle using at least one of regenerative braking and hydraulic braking.

In addition, in the control method of a brake system configured to perform cooperative braking in which regenerative braking and hydraulic braking are performed together in a braking situation of the vehicle, (a) when the brake pedal is depressed, the pedal travel sensor calculating a total required braking force for braking the vehicle based on the stroke of the brake pedal measured by (b) calculating a required regenerative braking force based on the total required braking force; (c) driving the regenerative braking unit to have braking power equal to the required regenerative braking power; (d) determining whether regenerative braking should be stopped; (e) when it is determined that regenerative braking should be stopped, calculating a hydraulic braking force required according to stopping regenerative braking; (f) calculating a required displacement of the motor piston according to the required hydraulic braking force; (g) driving the electric booster unit to pressurize the reaction disk by moving the motor piston by the required displacement; And (h) while the motor piston is moved by the required displacement, one end is in contact with the brake pedal and the other end is in contact with a part of the electric booster unit, and a process of performing control so that the magnitude of the leg force is maintained as a whole using an elastic body and a reaction disk. A brake system control method is provided.

As described above, according to the present embodiment, the brake system of a vehicle performing regenerative braking and hydraulic braking uses a reaction disk made of an elastic material, in a situation where the total braking force is maintained but the regenerative braking force decreases and the hydraulic braking force increases. , there is an effect of preventing the driver from feeling a sense of difference in stepping.

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.
도 5는 제동 중 제어부가 회생제동만을 수행하는 상황에서 회생제동을 해제하는 동안에 답입량이 증가하는 경우 시간에 따른 총 답력, 탄성체의 답력, 리액션디스크의 답력, 회생제동력 및 유압제동력의 관계를 설명하기 위한 그래프이다.
도 6은 도 5에서 시작점,

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.
도 7은 제동 중 제어부가 회생제동 및 유압제동을 수행하는 상황에서 회생제동을 해제하는 경우 시간에 따른 총 답력, 탄성체의 답력, 리액션디스크의 답력, 회생제동력 및 유압제동력의 관계를 설명하기 위한 그래프이다.
도 8은 도 7에서 시작점,

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.
도 9는 제동 중 제어부가 회생제동과 유압제동을 함께 수행하는 상황에서 회생제동을 해제하는 동안에 답입량이 증가하는 경우 시간에 따른 총 답력, 탄성체의 답력, 리액션디스크의 답력, 회생제동력 및 유압제동력의 관계를 설명하기 위한 그래프이다.
도 10은 도 9에서 시작점,

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.
도 11은 본 개시의 일 실시예에 따른 브레이크 시스템 제어방법의 흐름도이다.1 is a cross-sectional view of a brake system according to an embodiment of the present disclosure.
2 is a schematic diagram for explaining the relationship between a reaction disk having an elastic material, an operating rod and a motor piston, and a leg force.
FIG. 3 is a graph for explaining the relationship between total pedal force, elastic body pedal force, reaction disk pedal force, regenerative braking force, and hydraulic braking force over time when regenerative braking is released in a situation where the controller only performs regenerative braking during braking.
Figure 4 is the starting point in Figure 3,

, and

It is a schematic diagram for explaining the operation at the point of in.
FIG. 5 illustrates the relationship among total pedal force, elastic body pedal force, reaction disk pedal force, regenerative braking force, and hydraulic braking force over time when the amount of depression increases while regenerative braking is released in a situation where the control unit only performs regenerative braking during braking. It is a graph for
6 is a starting point in FIG. 5;

, and

It is a schematic diagram for explaining the operation at the point of in.
7 is a graph for explaining the relationship between total pedal force, elastic body pedal force, reaction disk pedal force, regenerative braking force, and hydraulic braking force over time when regenerative braking is released in a situation where a controller performs regenerative braking and hydraulic braking during braking. to be.
8 is a starting point in FIG. 7;

, and

It is a schematic diagram for explaining the operation at the point of in.
9 is a graph showing the total pedal force, the elastic body pedal force, the reaction disk pedal force, the regenerative braking force, and the hydraulic braking force over time when the amount of depression increases while regenerative braking is released in a situation in which the control unit performs both regenerative braking and hydraulic braking during braking. It is a graph to explain the relationship of
10 is a starting point in FIG. 9;

, and

It is a schematic diagram for explaining the operation at the point of in.
11 is a flowchart of a brake system control method according to an embodiment of the present disclosure.

Hereinafter, some embodiments of the present disclosure will be described in detail through exemplary drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible, even if they are displayed on different drawings. In addition, in describing the present disclosure, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present disclosure, the detailed description will be omitted.

In describing the components of the embodiment according to the present disclosure, symbols such as first, second, i), ii), a), and b) may be used. These codes are only for distinguishing the component from other components, and the nature or sequence or order of the corresponding component is not limited by the codes. In the specification, when a part is said to 'include' or 'include' a certain component, it means that it may further include other components, not excluding other components unless explicitly stated otherwise. .

1 is a cross-sectional view of a brake system according to an embodiment of the present disclosure.

Referring to FIG. 1 , a brake system 1 according to an embodiment of the present disclosure includes a pedal master unit 10, an electric booster unit 20, and a housing 30. ), a disc unit (42) and a control unit (electric control unit, 50).

The pedal master unit 10 includes all or part of a pedal 11, a rod assembly 60, a push rod 13, a master cylinder 14, and a return spring 15. do.

The pedal 11 is a part that the driver presses to decelerate or stop the vehicle. When the driver pushes down on the pedal 11 to press one end of the operating rod 12 to a certain pressure or higher, the operating rod 12 moves toward the reaction disc 420. At this time, the stroke of the pedal 11 may be sensed by a separately provided pedal travel sensor (not shown). One end of the operating rod 12 may be placed in contact with the central portion of the reaction disk 420 .

The rod assembly 60 includes an operating rod 12, an elastic body 17, and an elastic body connecting portion 16.

The operating rod 12 is a medium that transfers the driver's pedal effort to the reaction disk 420. One end of the operating rod 12 is connected to the pedal 11. The operating rod 12 may pressurize the master cylinder 14 by pushing the reaction disk 420 together with the motor piston 28 toward the master cylinder 14 side. In an initial state where the depression of the pedal 11 starts, the other end of the operating rod 12 may be spaced apart from the reaction disk 420 . As the pedal 11 is depressed, the other end of the operating rod 12 moves forward toward the reaction disk 420.

One end of the elastic body 17 is in contact with the operating rod 12, and the other end is disposed to be in contact with the elastic body connecting portion 16. As shown in FIG. 1, the elastic body connection part 16 may be formed on one side of the screw shaft, but as shown in FIG. 4, a part of the other side opposite to the side where the motor piston 28 comes into contact with the reaction disk 420. can be formed in In addition, the elastic connecting portion 16 may be formed in a space that can move along with the linear motion of the motor piston 28 .

The elastic body 17 forms an elastic force according to the movement of the operating rod 12 . Specifically, when the driver depresses the pedal 11, the operating rod 12 compresses the elastic body 17 while moving in the direction toward the reaction disk 420. The compressed elastic body 17 forms a reaction force called elastic force and provides leg force to the driver. Since the other end of the elastic body 17 is disposed in contact with the elastic body connecting portion 16, the elastic body 17 is affected only by the displacement of the operating rod 12 and the displacement of the motor piston 28. Even if reaction force is not formed from the reaction disk 420 because the operating rod 12 is not in contact with the reaction disk 420, the driver can feel the leg force due to the reaction force generated by the elastic body 17.

The elastic body 17 may be composed of a spring or a combination of a spring 171 and a damper 172 . In the present disclosure, the spring 171 and the damper 172 are shown as being connected in series, but are not necessarily limited thereto, and the spring 171 and the damper 172 may be connected in parallel.

At least a part of the push rod 13 is inserted into the master cylinder 14 . The push rod 13 reciprocates in the longitudinal direction of the master cylinder 14 inside the master cylinder 14, and when the push rod 13 moves forward, the brake fluid stored inside the master cylinder 14 is pressurized. can do.

The master cylinder 14 is configured to contain brake fluid therein. The brake fluid inside the master cylinder 14 is pressurized and hydraulic pressure used for braking is formed. The formed hydraulic pressure is transmitted to a plurality of wheel brakes (not shown).

The return spring 15 is disposed inside the master cylinder 14, and is compressed or expanded by the reciprocating motion of the push rod 13. The return spring 15 may preferably be a coil spring. However, the present disclosure is not necessarily limited thereto and may be composed of an elastic body such as a leaf spring or rubber. Also, although not shown in the present disclosure, the return spring 15 may be disposed inside the housing of the electric booster unit 20 . The return spring 15 is inside the master cylinder 14 or inside the electric booster 20 so as to be pressed by a portion of the force transmitted by any one or more of the operating rod 12 or the electric booster 20. can be placed.

The electric booster unit 20 is configured to boost the driving force of the driver. The electric booster unit 20 includes all or part of a motor 22, a gear device 24, a screw shaft 26, and a motor piston 28.

The motor 22 is configured to rotate in a forward or reverse direction around an axis of the motor 22 according to a signal from the control unit 50 .

The gear device 24 is configured to transmit rotational torque of the motor 22 to the screw shaft 26. The gear unit 24 includes all or part of a first gear 240 , a second gear 242 , and a third gear 244 .

The first gear 240 primarily receives rotational torque transmitted from the motor 22 and transmits it to the second gear 242 . The second gear 242 transfers the rotational torque received from the first gear 240 to the third gear 244 . The third gear 244 transmits the rotational torque received from the second gear 242 to the screw shaft 26 . Based on the ratio of the number of teeth of the first gear 240 to the third gear 244, the rotational speed decreases at a certain rate while the rotational torque is transmitted to the first gear 240 to the third gear 244, or can increase

The screw shaft 26 is configured to convert the rotational torque transmitted by the gear unit 24 into linear motion. The screw shaft 26 includes all or part of a first shaft 260 and a second shaft 262 .

The first shaft 260 is constrained to the third gear 244 to rotate. The second shaft 262 is configured to convert rotational motion of the first shaft 260 into linear motion. Preferably, the first shaft 260 may be configured as a pinion and the second shaft 262 may be configured as a rack. One end of the second shaft 262 is connected to the motor piston 28 . Due to this, as the motor 22 is driven, the second shaft 262 performs forward movement toward the reaction disk 420 or backward movement in the opposite direction.

The motor piston 28 reciprocates in the longitudinal direction of the master cylinder 14 by the force transmitted by the combination of the gear unit 24 and the screw shaft 26. The motor piston 28 is disposed so that one side is pressed by the second shaft 262 and the other side presses the reaction disk 420 .

The motor piston 28 is disposed close to the first shaft 260 when the pedal 11 is not pressed, that is, when there is no braking request signal.

The housing 30 is formed to surround at least a portion of the pedal master unit 10 , at least a portion of the electric booster unit 20 and at least a portion of the disk unit 42 .

When the control unit 50 performs hydraulic braking, the disc unit 42 presses the master cylinder 14 to provide hydraulic pressure to a plurality of wheel brakes (not shown). The disk unit 42 includes a reaction disk 420 and a reaction disk container 422 .

The reaction disk 420 is arranged to be pressed by at least one of the operating rod 12 and the motor piston 28 . In FIG. 1 of the present disclosure, the reaction disk 420 and the motor piston 28 are shown in contact. However, if a braking request signal is not generated by the controller 50, the motor piston 28 may be in a state of being spaced apart from the reaction disk 420.

The reaction disk 420 is arranged so that the outer circumference of the reaction disk 420, that is, the outer circumference, is pressed by the motor piston 28, and the center of the reaction disk 420 is pressed by the operating rod 12. can To this end, the longitudinal section of the motor piston 28 may be formed in a substantially annular shape, and the operating rod 12 may pass through a hollow formed in the center of the motor piston 28 . At this time, the operating rod 12 and the reaction disk 420 are disposed coaxially. Meanwhile, the present disclosure is not limited thereto, and any brake system configured with a device capable of pressurizing the reaction disk 420 due to depression of the pedal 11 and driving of the motor 22 is included in the present disclosure.

The reaction disk 420 is made of a compressible elastic material. For example, at least a part of the reaction disk 420 may be formed of a rubber material. When the reaction disk 420 is pressurized by one or more of the operating rod 12 and the motor piston 28, the reaction force formed by the pressurized force is transmitted to the driver through the operating rod 12, and the driver feels It forms part of pedal feel.

The reaction disk accommodating portion 422 is formed to accommodate at least a portion of the reaction disk 420 in an accommodating space formed therein. When one side of the reaction disk accommodating portion 422 is pressed by one or more of the operating rod 12 and the motor piston 28, the other side of the reaction disk accommodating portion 422 presses the push rod 13.

The total leg force provided to the driver may be determined as the sum of the leg force formed by the reaction disk 420 to the compressive force and the leg force formed by the reaction force to the compressive force of the elastic body 17 .

The controller 50 forms a braking request signal based on the depression signal received from the pedal travel sensor (not shown). The braking request signal is an electrical signal that causes at least a portion of a plurality of wheel brakes (not shown) to form a braking force.

The control unit 50 calculates a total required braking force for braking the vehicle based on the depression signal. In addition, the controller 50 determines whether to perform one or more of regenerative braking and hydraulic braking, and applies regenerative braking force or controls the electric booster unit 20 differently depending on whether regenerative braking and/or hydraulic braking is performed. can do. Here, the total required braking force may be a value obtained by adding the hydraulic braking force and the regenerative braking force. A plurality of modes may be set in the braking mode. For example, the controller 50 sets a hydraulic braking mode for braking using only hydraulic braking force, a regenerative braking mode for braking using only regenerative braking force, and a cooperative braking mode for braking using both hydraulic braking force and cooperative braking force to brake the vehicle. can

2 is a schematic diagram for explaining the relationship between a reaction disk having an elastic material, an operating rod and a motor piston, and a leg force.

2(a) is a schematic diagram for explaining the leg force according to the displacement of the operating rod 12 in a state where the displacement of the reaction disk 420 does not change. 2(b) is a schematic diagram for explaining the leg force according to the magnitude of the pressure applied in the master cylinder 14 when the relative displacement of the motor piston 28 and the operating rod 12 is constant. .

Referring to (a) of FIG. 2 , it can be confirmed that the leg force increases when the operating rod 12 moves toward the reaction disk 420 and decreases when the operating rod 12 moves in the opposite direction. However, when the difference between the displacement of the operating rod 12 and the displacement of the reaction disk 420 is within a certain range, there is almost no change in the effort felt by the driver. This is due to the fact that the reaction disk 420 is made of an elastic material.

Referring to (b) of FIG. 2, the difference between the displacement of the motor piston 28 and the displacement of the operating rod 12 is kept constant, and the hydraulic pressure in the master cylinder 14 is increased by pressing the reaction disk 420. In this case, the leg force felt by the driver increases according to the hydraulic pressure in the master cylinder 14, not the displacement of the motor piston 28 and the operating rod 12, respectively.

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.FIG. 3 is a graph for explaining the relationship between total pedal force, elastic body pedal force, reaction disk pedal force, regenerative braking force, and hydraulic braking force over time when regenerative braking is released in a situation where the controller only performs regenerative braking during braking. Figure 4 is the starting point in Figure 3,

, and

It is a schematic diagram for explaining the operation at the point of in.

은 총 답력,

는 탄성체(17)의 답력,

는 리액션디스크(420)의 답력,

는 회생제동력, 및

는 유압제동력을 나타낸다.In the graphs shown in FIGS. 3, 5, 7 and 9 below,

silver total answer,

Is the leg force of the elastic body 17,

Is the leg force of the reaction disk 420,

is the regenerative braking force, and

represents the hydraulic braking force.

시점에서의 동작, 및 도 4의 (c)는 도 3의

시점에서의 동작을 도시하고 있다.Figure 4 (a) is the operation at the starting point of Figure 3, Figure 4 (b) is the

Operation at the point of view, and Figure 4 (c) of Figure 3

It shows the operation at the point of view.

)으로서 총 답력(

)이 형성된다. 오퍼레이팅 로드(12)가 리액션디스크(420)의 중앙부(423)와 이격된 상태에 있으므로 리액션디스크(420)의 반력에 의한 답력(

)은 아직 형성되지 않는다. 운전자가 페달(11)을 답입하는 초기 지점인 시작점과

시점 사이의 구간에서는 탄성체의 답력(

)만이 증가한다.The starting point of FIG. 3 is the point at which the driver starts to press the pedal 11 (

) as the total power (

) is formed. Since the operating rod 12 is in a state of being spaced apart from the central portion 423 of the reaction disk 420, the leg force by the reaction force of the reaction disk 420 (

) is not yet formed. The starting point, which is the initial point at which the driver presses the pedal 11, and

In the section between the viewpoints, the leg force of the elastic body (

) only increases.

시점과

사이의 구간에서는 리액션디스크(420)의 반력에 의한 답력(

)이 증가한다. 모터피스톤(28)이 마스터실린더(14)측 방향으로 이동하여 디스크부(42)를 가압하여, 리액션디스크(420)의 중앙에 돌출되는 중앙부(423)가 형성된다. 중앙부(423)는

시점에 오퍼레이팅 로드(12)와 접한다. 디스크부(42)가 가압되는 정도가 증가할수록 리액션디스크(420)의 반력으로 인해 오퍼레이팅 로드(12)를 통하여 운전자에게 답력을 제공한다. 따라서 이 구간에서는 페달(11)의 답입량에 상응하는 총 답력(

)은 증가한다. 다만 모터피스톤(28)이 마스터실린더(14)측 방향으로 이동하여 탄성체(17)가 팽창됨에 따라 탄성체(17)에 의한 답력의 증가폭은 총 답력(

)의 증가폭만큼 증가하지 않을 수 있다.

point of view and

In the interval between, the leg force by the reaction force of the reaction disk 420 (

) increases. The motor piston 28 moves toward the master cylinder 14 and presses the disk unit 42 so that a central portion 423 protruding from the center of the reaction disk 420 is formed. The central portion 423 is

At the point of view, it comes into contact with the operating rod 12. As the degree of pressurization of the disk unit 42 increases, a reaction force of the reaction disk 420 provides a driver with a leg force through the operating rod 12 . Therefore, in this section, the total pressing force corresponding to the depression amount of the pedal 11 (

) increases. However, as the motor piston 28 moves in the direction of the master cylinder 14 and the elastic body 17 expands, the increase in the leg force by the elastic body 17 is the total leg force (

) may not increase as much as the increase in

시점 사이의 구간에서는 제동력이 형성되지 않는다. starting point and

The braking force is not formed in the section between viewpoints.

시점과

시점 사이의 구간은 운전자의 페달(11) 답입량이 증가하면서 그에 따른 제동력이 형성되는 구간이다. 도 3에서는 제어부(50)가 회생제동모드를 개시하여 차량을 제동하는 경우로서, 이 구간에서는 유압제동력(

)은 형성되지 않는 동시에 회생제동력(

)이 점진적으로 증가한다.

point of view and

The section between viewpoints is a section in which braking force is formed as the driver's depression amount of the pedal 11 increases. In FIG. 3, the control unit 50 starts the regenerative braking mode to brake the vehicle, and in this section, the hydraulic braking force (

) is not formed and at the same time regenerative braking force (

) gradually increases.

시점과

시점 사이의 구간은 운전자의 페달(11) 답입량이 유지되는 구간이다. 이 구간에서는 운전자가 요구하는 제동력의 크기가 변하지 않으므로 회생제동력(

) 또한 일정하게 유지된다.

시점에서는 도 4의 (b)와 같이 모터피스톤(28)이 디스크부(42)를 가압하여 디스크부(42)의 변위가 도 4에 도시된

에서

로 이동하지만, 유압제동력(

)을 형성할 정도로 이동하지 않는다.

point of view and

The section between the viewpoints is a section in which the driver's depression amount of the pedal 11 is maintained. In this section, the amount of braking force requested by the driver does not change, so the regenerative braking force (

) is also kept constant.

At this point, the motor piston 28 presses the disk unit 42 as shown in FIG.

at

, but the hydraulic braking force (

) does not move enough to form

시점과

시점 사이의 구간은 제어부(50)가 회생제동모드를 해제하고 유압제동모드를 개시하는 구간이다. 이 구간에서는 회생제동력(

)은 감소하고, 감소된 제동력만큼 유압제동력(

)이 증가한다.

시점과

시점 사이의 구간은 유압제동력(

)이 증가되는 구간이다. 본 개시의 일 실시예에 따른 브레이크 시스템은,

시점과

시점 사이의 구간에서 유압제동력을 발생시키기 위해 전동부스터부(20)를 구동하여 모터피스톤(28)을

에서

으로 이동시켜 마스터실린더(14)를 가압한다.

지점이 되면 도 4의 (c)에 도시된 바와 같이, 오퍼레이팅 로드(12)의 변위는

에서 변하지 않고 모터피스톤(28)의 변위만 변하게 된다.

point of view and

The section between the viewpoints is a section in which the control unit 50 releases the regenerative braking mode and starts the hydraulic braking mode. In this section, regenerative braking (

) is reduced, and the hydraulic braking force (

) increases.

point of view and

The interval between the viewpoints is the hydraulic braking force (

) is an increasing interval. A brake system according to an embodiment of the present disclosure,

point of view and

In order to generate hydraulic braking force in the section between the viewpoints, the motor piston 28 is driven by driving the electric booster unit 20.

at

to pressurize the master cylinder 14.

When the point is reached, as shown in (c) of FIG. 4, the displacement of the operating rod 12 is

Only the displacement of the motor piston 28 is changed without changing in .

이라 하고, 도 4의 (c)에서 운전자가 느끼는 답력을

라고 할 때,

및

는 수학식 1을 만족한다.In (b) of FIG. 4, the driver feels the effort

, and the pedal force felt by the driver in (c) of FIG.

When you say

and

satisfies Equation 1.

는 도 4의 (b)에서 리액션디스크(420)가 오퍼레이팅 로드(12)에게 가하는 압력,

는 도 4의 (b)에서 리액션디스크(420)와 오퍼레이팅 로드(12)가 접하는 면적,

는 탄성체(17)의 탄성계수,

는 도 4의 (b)에서 탄성체(17)가 압축된 거리,

는 도 4의 (c)에서 리액션디스크(420)가 오퍼레이팅 로드(12)에게 가하는 압력, 및

는 도 8의 (c)에서 탄성체(17)가 압축된 거리를 의미한다.here,

Is the pressure applied by the reaction disk 420 to the operating rod 12 in FIG. 4 (b),

Is the contact area between the reaction disk 420 and the operating rod 12 in FIG. 4 (b),

Is the elastic modulus of the elastic body 17,

is the compressed distance of the elastic body 17 in FIG. 4 (b),

Is the pressure applied to the operating rod 12 by the reaction disk 420 in FIG. 4 (c), and

Means the distance at which the elastic body 17 is compressed in FIG. 8(c).

지점으로 유지되고 있는 반면에 모터피스톤(28)의 변위가

지점에서

지점으로 이동하므로

이다. 따라서

이다.Between FIG. 4(b) and FIG. 4(c), the displacement of the operating rod 12

The displacement of the motor piston 28 while remaining at the point

at the branch

as it moves to the point

to be. therefore

to be.

). 이 경우 리액션디스크(420)의 중앙부(423)의 돌출되는 증가하더라도 중앙부(423)와 오퍼레이팅 로드(12)가 서로 접하는 면적에는 변화가 없다.In (c) of FIG. 4 , the motor piston 28 is further advanced toward the master cylinder 14 because the hydraulic braking force must be increased by the reduced regenerative braking force. Since the motor piston 28 presses the reaction disk 420 more strongly while maintaining the displacement of the operating rod 12, the central portion 423 of the reaction disk 420 having an elastic material protrudes more, and the reaction disk (420) will have a greater pressure (

). In this case, even if the protrusion of the central portion 423 of the reaction disk 420 increases, there is no change in the contact area between the central portion 423 and the operating rod 12 .

이지만,

이므로

이다. 따라서 운전자는 회생제동력이 감소하고 유압제동력이 증가하는 동안에도 이질감 없는 답력을 느낄 수 있다.

as,

Because of

to be. Therefore, the driver can feel the pedal power without any heterogeneity even while the regenerative braking force decreases and the hydraulic braking force increases.

가 되도록 하는 리액션디스크(420)를 설계하여 회생제동력이 감소하고 유압제동력이 증가하는 동안에도 운전자가 느끼는 답력인

과

의 차이가 없도록 하는 것이 바람직하다.In the present disclosure, the reaction disk 420 is made of an elastic material, and the degree of protrusion and the area in contact with the operating rod 12 may vary depending on the difference in the degree of elasticity of the reaction disk 420 .

By designing the reaction disk 420 so that the regenerative braking force decreases and the hydraulic braking force increases, the driver feels the leg force

class

It is desirable that there be no difference in

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.FIG. 5 illustrates the relationship among total pedal force, elastic body pedal force, reaction disk pedal force, regenerative braking force, and hydraulic braking force over time when the amount of depression increases while regenerative braking is released in a situation where the control unit only performs regenerative braking during braking. It is a graph for 6 is a starting point in FIG. 5;

, and

It is a schematic diagram for explaining the operation at the point of in.

시점에서의 동작, 및 도 6의 (c)는 도 5의

시점에서의 동작을 도시하고 있다. 여기서, 도 5에 도시된 그래프의 시작점과

시점 사이 구간에서 브레이크 시스템의 동작은 도 3에 도시된 그래프의 시작점과

시점 사이 구간에서의 동작과 유사하므로 이하 설명은 생략한다.Figure 6 (a) is the operation at the starting point of Figure 5, Figure 6 (b) is the

Operation at the point of view, and FIG. 6 (c) of FIG.

It shows the operation at the point of view. Here, the starting point of the graph shown in FIG. 5 and

The operation of the brake system in the interval between the viewpoints is the starting point of the graph shown in FIG.

Since it is similar to the operation in the section between viewpoints, the following description is omitted.

시점에서는 제어부(50)가 회생제동모드를 해제하고 유압제동모드를 설정하기 시작하는 지점이다.

시점과

시점 사이의 구간에서는 회생제동력(

)이 감소하고 유압제동력(

)이 증가하게 되는데, 도 5에 도시된 바와 같이 이 구간에서 운전자가 답입량을 증가시키므로 요구 유압제동력(

)은 기존의 회생제동력(

)의 최대 제동력보다 더 크다.

At this point, the control unit 50 releases the regenerative braking mode and starts setting the hydraulic braking mode.

point of view and

In the section between the viewpoints, the regenerative braking force (

) decreases and the hydraulic braking force (

) increases. As shown in FIG. 5, as the driver increases the amount of depression in this section, the required hydraulic braking force (

) is the existing regenerative braking power (

) is greater than the maximum braking force of

시점과

시점 사이의 구간에서보다 도 5의

시점과

시점 사이의 구간에서 유압제동력(

)이 증가하는 차이가 더 크다.of Figure 3

point of view and

5 than in the interval between the viewpoints.

point of view and

Hydraulic braking force in the section between viewpoints (

) increases, the difference is larger.

In the brake system according to an exemplary embodiment of the present disclosure, even in this case, the driver does not feel a sense of difference in stepping. It is explained in detail below.

에서

으로 이동하게 된다. 모터피스톤(28) 역시 전동부스터부(20)의 구동에 의해 디스크부(42)를 가압하고, 이로 인해 디스크부(42)의 변위가

에서

로 이동하면서 마스터실린더(14)를 가압해 유압을 생성하게 된다. 리액션디스크(420)에게 가압되는 압력이 점점 증가함에 따라 그에 대한 반력으로 중앙부(423)는 더욱 돌출되고 오퍼레이팅 로드(12)에게 가하는 압력이 증가하게 된다. 그 결과 리액션디스크(420)의 반력에 의한 답력(

)의 크기가 증가하게 되지만, 탄성체(17)가 팽창함에 따라 탄성체(17)에 의한 답력(

)의 크기는 감소하게 된다. 이는 상기 수학식 1에 대해 설명한 원리가 그대로 적용되어, 마스터실린더(14) 내 유압이 변하더라도 운전자는 답입에 대한 이질감을 느끼지 않을 수 있다. 즉, 모터피스톤(28)이 리액션디스크(420)를 가압하여 리액션디스크(420)의 답력(

)이 증가하는 동시에, 모터피스톤(28)이 마스터실린더(14)측으로 이동함에 따라 탄성체(17)가 팽창하여 탄성체(17)의 답력(

)을 감소시키기 때문에 운전자는 답력에 대한 이질감을 느끼지 않는다.6(b) and 6(c), the displacement of the operating rod 12 increases as the driver increases the amount of depression.

at

will move to The motor piston 28 also presses the disk unit 42 by the driving of the electric booster unit 20, which causes the displacement of the disk unit 42.

at

While moving to pressurize the master cylinder 14 to generate hydraulic pressure. As the pressure applied to the reaction disk 420 gradually increases, the central portion 423 further protrudes as a reaction force thereto, and the pressure applied to the operating rod 12 increases. As a result, the leg force due to the reaction force of the reaction disk 420 (

) increases, but as the elastic body 17 expands, the leg force by the elastic body 17 (

) decreases in size. This is because the principle described in Equation 1 is applied as it is, so even if the hydraulic pressure in the master cylinder 14 changes, the driver may not feel a sense of difference in depression. That is, the motor piston 28 presses the reaction disk 420 so that the reaction disk 420 has a leg force (

) increases, and as the motor piston 28 moves toward the master cylinder 14, the elastic body 17 expands and the leg force of the elastic body 17 (

) is reduced, so the driver does not feel a sense of heterogeneity in the leg power.

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.7 is a graph for explaining the relationship between total pedal force, elastic body pedal force, reaction disk pedal force, regenerative braking force, and hydraulic braking force over time when regenerative braking is released in a situation where a controller performs regenerative braking and hydraulic braking during braking. to be. 8 is a starting point in FIG. 7;

, and

It is a schematic diagram for explaining the operation at the point of in.

시점에서의 동작, 및 도 8의 (c)는 도 7의

시점에서의 동작을 도시하고 있다.Figure 8 (a) is the operation at the starting point of Figure 7, Figure 8 (b) is the

Operation at the point of view, and FIG. 8 (c) of FIG.

It shows the operation at the point of view.

지점 사이 구간에서 브레이크 시스템의 답력 형성을 위한 동작은 도 3에서 도시된 그래프의 시작점과

지점 사이 구간에서의 동작과 유사하므로 이하 설명은 생략한다.Here, the starting point of the graph shown in FIG. 7 and

The operation for forming the leg force of the brake system in the section between the points is the starting point of the graph shown in FIG.

Since it is similar to the operation in the interval between points, the following description is omitted.

에 위치하고 있고, 총 답력(

)이 형성된다. 오퍼레이팅 로드(12)가 리액션디스크(420)의 중앙부(423)와 이격된 상태에 있으므로 리액션디스크(420)의 반력에 의한 답력(

)은 형성되지 않는다.At the starting point of FIG. 7, the operating rod 12 is the point at which the driver starts to press the pedal 11.

, and the total response force (

) is formed. Since the operating rod 12 is in a state of being spaced apart from the central portion 423 of the reaction disk 420, the leg force by the reaction force of the reaction disk 420 (

) is not formed.

시점과

시점 사이의 구간에서는 제동력이 형성되지 않는다. 이 구간에서는 탄성체(17)의 압축 및 리액션디스크(420)의 접촉에 의해 형성되는 답력(

)이 증가한다.The point at which the driver depresses the pedal 11

point of view and

The braking force is not formed in the section between viewpoints. In this section, the leg force formed by the compression of the elastic body 17 and the contact of the reaction disk 420 (

) increases.

시점과

시점 사이의 구간은 운전자의 페달(11) 답입량이 증가하면서 그에 따른 제동력이 형성되는 구간이다. 도 7의 경우에서는 제어부(50)가 우선 회생제동모드를 개시하여 차량을 제동하는 경우로서, 이 구간에서는 유압제동력(

)은 형성되지 않는 동시에 회생제동력(

)이 점진적으로 증가한다.

point of view and

The section between viewpoints is a section in which braking force is formed as the driver's depression amount of the pedal 11 increases. In the case of FIG. 7 , the control unit 50 first initiates the regenerative braking mode to brake the vehicle, and in this section, the hydraulic braking force (

) is not formed and at the same time regenerative braking force (

) gradually increases.

시점과

시점 사이의 구간은 운전자가 페달(11)을 더 답입하는 등 제어부(50)가 유압제동모드를 개시해야 한다고 판단하여 유압제동력(

)을 형성하는 구간이다. 이 구간에서는 회생제동력(

)은 유지되지만, 전동부스터부(20)가 구동되어 모터피스톤(28)을 가압하면서 복수의 휠브레이크(미도시)에게 공급하는 유압을 증가시킨다. 이러한 과정에서 오퍼레이팅 로드(12)는 마스터실린더(14)측으로 더 이동해 리액션디스크(420)의 돌출된 중앙부(423)를 가압하게 된다. 오퍼레이팅 로드(12)가 리액션디스크(420)의 중앙부(423)와 접하게 됨으로써 운전자는 리액션디스크(420)의 답력(

)을 추가적으로 느끼게 된다. 여기서 총 답력(

)은 탄성체(17)의 답력(

)과 리액션디스크(420)의 답력(

)을 더한 값이다.

point of view and

In the interval between the viewpoints, the hydraulic braking force (

) is a section that forms In this section, regenerative braking (

) is maintained, but the electric booster unit 20 is driven to increase the hydraulic pressure supplied to a plurality of wheel brakes (not shown) while pressing the motor piston 28. In this process, the operating rod 12 moves further toward the master cylinder 14 and presses the protruding central portion 423 of the reaction disk 420 . As the operating rod 12 comes into contact with the central portion 423 of the reaction disk 420, the driver presses the reaction disk 420's leg force (

) is felt additionally. Total response here (

) is the leg force of the elastic body 17 (

) and the effort of the reaction disk 420 (

) is the sum of

시점과

시점 사이의 구간은 운전자의 페달(11) 답입량이 유지되는 구간이다. 이 구간에서는 운전자가 요구하는 제동력의 크기가 변하지 않으므로 회생제동력(

) 및 유압제동력(

) 또한 일정하게 유지된다.

시점에서는 도 8의 (b)와 같이 모터피스톤(28)이 리액션디스크(420)를 가압하여 디스크부(42)의 변위가 도 8에 도시된

로 이동하고, 유압제동력(

)의 형성이 시작되는 지점인

지점을 지난다. 모터피스톤(28)의 가압으로 인해 리액션디스크(420)의 중앙부(423)가 도 8의 (a)에서보다 더 돌출되고, 오퍼레이팅 로드(12)와 접한다. 이 구간에서는 운전자가 유압제동력(

)을 형성하기 위해 답입량을 증가시킴에 따라 오퍼레이팅 로드(12)의 변위도

로 이동한다.

point of view and

The section between the viewpoints is a section in which the driver's depression amount of the pedal 11 is maintained. In this section, the amount of braking force requested by the driver does not change, so the regenerative braking force (

) and hydraulic braking force (

) is also kept constant.

At this point, the motor piston 28 presses the reaction disk 420 as shown in FIG.

, and the hydraulic braking force (

), which is the point at which the formation of

pass the point Due to the pressurization of the motor piston 28, the central portion 423 of the reaction disk 420 protrudes more than in FIG. 8(a) and contacts the operating rod 12. In this section, the driver has hydraulic braking force (

) The displacement of the operating rod 12 as the amount of depression is increased to form

go to

시점과

시점 사이의 구간은 제어부(50)가 회생제동모드를 해제하고, 감소된 회생제동력의 크기만큼 유압제동력을 증가시키는 구간이다.

point of view and

The section between the viewpoints is a section in which the control unit 50 releases the regenerative braking mode and increases the hydraulic braking force by the amount of the reduced regenerative braking force.

시점과

시점 사이의 구간에서 유압제동력을 증가시키기 위해 전동부스터부(20)를 구동하여 모터피스톤(28)을

에서

으로 이동시켜 마스터실린더(14)를 더 가압한다.

시점이 되면 도 8의 (c)에 도시된 바와 같이, 오퍼레이팅 로드(12)의 변위는

에서 변하지 않고 모터피스톤(28)의 변위만 변하게 된다. 오퍼레이팅 로드(12)는 계속 리액션디스크(420)와 접하고 있으므로, 총 답력(

)은 탄성체(17)의 답력(

) 및 리액션디스크(420)의 답력(

)의 영향을 받는다. 다만, 리액션디스크(420)의 답력(

)의 영향을 받는다 하더라도 총 답력(

)의 크기는 상기 수학식 1에 대해 설명한 바와 같이 변하지 않는다. 즉, 모터피스톤(28)이 리액션디스크(420)를 가압하여 리액션디스크(420)의 답력(

)이 증가하는 동시에, 모터피스톤(28)이 마스터실린더(14)측으로 이동함에 따라 탄성체(17)가 팽창하여 탄성체(17)의 답력(

)을 감소시키기 때문에 운전자는 답력에 대한 이질감을 느끼지 않는다.A brake system according to an embodiment of the present disclosure,

point of view and

In order to increase the hydraulic braking force in the section between the viewpoints, the motor piston 28 is operated by driving the electric booster unit 20.

at

to further pressurize the master cylinder 14.

At this point, as shown in (c) of FIG. 8, the displacement of the operating rod 12

Only the displacement of the motor piston 28 is changed without changing in . Since the operating rod 12 is in continuous contact with the reaction disk 420, the total effort (

) is the leg force of the elastic body 17 (

) and the reaction force of the disk 420 (

) is affected by However, the leg force of the reaction disk 420 (

), even if it is affected by the total effort (

) does not change as described in Equation 1 above. That is, the motor piston 28 presses the reaction disk 420 so that the reaction disk 420 has a leg force (

) increases, and as the motor piston 28 moves toward the master cylinder 14, the elastic body 17 expands and the leg force of the elastic body 17 (

) is reduced, so the driver does not feel a sense of heterogeneity in the leg power.

, 및

인 시점에서의 동작을 설명하기 위한 개략도이다.9 is a graph showing the total pedal force, the elastic body pedal force, the reaction disk pedal force, the regenerative braking force, and the hydraulic braking force over time when the amount of depression increases while regenerative braking is released in a situation in which the control unit performs both regenerative braking and hydraulic braking during braking. It is a graph to explain the relationship of 10 is a starting point in FIG. 9;

, and

It is a schematic diagram for explaining the operation at the point of in.

시점에서의 동작, 및 도 10의 (c)는 도 9의

시점에서의 동작을 도시하고 있다. 여기서, 도 9에 도시된 그래프의 시작점과

시점 사이 구간에서 브레이크 시스템의 동작은 도 7에 도시된 그래프의 시작점과

시점 사이 구간에서의 동작과 유사하므로 이하 설명은 생략한다.Figure 10 (a) is the operation at the starting point of Figure 9, Figure 10 (b) is the

Operation at the point of view, and FIG. 10(c) of FIG. 9

It shows the operation at the point of view. Here, the starting point of the graph shown in FIG. 9 and

The operation of the brake system in the section between the viewpoints is the starting point of the graph shown in FIG.

Since it is similar to the operation in the section between viewpoints, the following description is omitted.

시점에서는 제어부(50)가 회생제동모드를 해제하고 유압제동력(

)을 증가시키기 위해 전동부스터부(20)를 구동하는 지점이다.

시점과

시점 사이의 구간에서는 회생제동력(

)이 감소하고 유압제동력(

)이 증가하게 되는데, 도 9에 도시된 바와 같이 이 구간에서 운전자가 답입량을 증가시키므로 요구 유압제동력(

)은 기존의 회생제동력(

)의 최대 제동력보다 더 크다.

At this point, the control unit 50 releases the regenerative braking mode and the hydraulic braking force (

) is the point at which the electric booster unit 20 is driven to increase.

point of view and

In the section between the viewpoints, the regenerative braking force (

) decreases and the hydraulic braking force (

) increases. As shown in FIG. 9, as the driver increases the amount of depression in this section, the required hydraulic braking force (

) is the existing regenerative braking power (

) is greater than the maximum braking force of

시점과

시점 사이의 구간에서보다 도 9의

시점과

시점 사이의 구간에서 유압제동력(

)이 증가하는 변화량이 더 크다.of Figure 7

point of view and

9 than in the interval between the viewpoints.

point of view and

Hydraulic braking force in the section between viewpoints (

) increases, the greater the change.

In the brake system according to an exemplary embodiment of the present disclosure, even in this case, the driver does not feel a sense of difference in stepping.

에서

으로 이동하게 된다. 모터피스톤(28) 역시 전동부스터부(20)의 구동에 의해 리액션디스크(420)를 가압하고, 이로 인해 디스크부(42)의 변위가

에서

로 이동하면서 마스터실린더(14)를 가압해 유압이 증가하게 된다. 도 10의 (b)에서 도 10의 (c)로 구동되는 동안에, 오퍼레이팅 로드(12)는 리액션디스크(420)의 중앙부(423)와 계속 접하고 있으나, 수학식 1에 대한 설명에서 설명한 바와 같이 운전자가 느끼는 답력은 거의 변함이 없다. 따라서 마스터실린더(14) 내 유압이 변하더라도 운전자는 답입에 대한 이질감을 느끼지 않는다.As shown in FIGS. 10(b) and 10(c), the displacement of the operating rod 12 increases as the driver increases the stepping amount.

at

will move to The motor piston 28 also presses the reaction disk 420 by driving the electric booster unit 20, which causes displacement of the disk unit 42.

at

While moving to pressurize the master cylinder 14, the hydraulic pressure is increased. While being driven from FIG. 10(b) to FIG. 10(c), the operating rod 12 continues to contact the central portion 423 of the reaction disk 420, but as described in the description of Equation 1, the driver The feeling of response is almost unchanged. Therefore, even if the hydraulic pressure in the master cylinder 14 changes, the driver does not feel a sense of difference in the depression.

11 is a flowchart of a brake system control method according to an embodiment of the present disclosure. The flowchart shown in FIG. 11 is a description of some of the many braking methods, and the control unit 50 does not necessarily include the algorithm of FIG. 11, but may include a plurality of braking algorithms including this. In the case of FIG. 11 , as a flowchart prepared under the premise that the regenerative braking unit is driven, the control unit 50 may include other methods of braking by driving only hydraulic braking force.

The controller 50 receives a brake pedal signal (S10). That is, the control unit 50 receives the signal of the brake pedal 11 to determine whether the driver presses the pedal 11 or not. When the brake pedal signal is not received, the controller 50 determines that a braking situation does not occur and does not proceed with the control process of FIG. 11 .

When receiving the brake pedal signal, the control unit 50 calculates the total required braking force (S20). The total required braking force is determined according to the amount of depression of the pedal 11 by the driver, and may be additionally determined by the control unit 50 equipped with the autonomous driving function. The control unit 50 calculates a total required braking force for braking the vehicle based on a depression amount of the pedal 11 measured by a pedal travel sensor (not shown) when the driver depresses the pedal 11 .

The controller 50 calculates the required regenerative braking force based on the total required braking force (S20). After calculating the required regenerative braking force, the control unit 50 drives a regenerative braking unit (not shown) based on the calculated required regenerative braking force (S40).

While the regenerative braking unit (not shown) is operating, the control unit 50 determines whether to stop regenerative braking (S50). The controller 50 may directly determine whether or not to stop regenerative braking, but may determine whether to stop regenerative braking using a regenerative braking stop signal received from the outside.

When it is determined that regenerative braking is stopped, the control unit 50 calculates the hydraulic braking force required according to the stop of regenerative braking (S60). When the controller 50 releases the regenerative braking mode, the regenerative braking force decreases. The controller 50 detects the magnitude of the reduced regenerative braking force and calculates a required hydraulic braking force to compensate for the detected braking force.

The control unit 50 calculates the required displacement of the motor piston 28 according to the requested hydraulic braking force (S70). Here, the required displacement of the motor piston 28 is determined based on the displacement of the motor piston 28 at the point at which the controller 50 starts to stop regenerative braking.

The control unit 50 drives the electric booster unit 20 so that the motor piston 28 moves by the required displacement (S80). The control unit 50 moves the motor piston 28 toward the master cylinder 14 so as to press the reaction disk 420 by driving the electric booster unit 20 . Here, the reaction disk 420 has an elastic material, and the motor piston 28 may come into contact with the outer portion of the reaction disk 420 .

While the motor piston 28 is moved by the required displacement, the control unit 50 uses the elastic body 17 and the reaction disk 420 to control the amount of leg force felt by the driver as a whole (S90).

Here, the elastic body 17 has one end in contact with the brake pedal 11 and the other end in contact with a part of the electric booster unit 20, and when the motor piston 28 moves toward the master cylinder 14 side, the driver's effort can be reduced. have.

While the motor piston 28 presses the reaction disk 420, the central portion 423 of the reaction disk 420 may protrude toward the operating rod 12 side. When the protruding reaction disk 420 comes into contact with the operating rod 12, it provides a reaction force to the operating rod 12, and this reaction force is a part of the pedal force felt by the driver. In the present disclosure, as described in Equation 1 above, even if the reaction disk 420 and the operating rod 12 come into contact with each other, no sense of difference in stepping is felt in a section where the regenerative braking force decreases and the hydraulic braking force increases.

After completing the process S90, this algorithm ends.

The braking logic for FIGS. 3 to 11 is exemplary, and the present disclosure does not necessarily reduce the driver's sense of discomfort for the braking logic shown in the drawings, and the driver feels the difference in the feeling of pressing in any braking logic. It has an effect that is not felt.

The above description is merely an example of the technical idea of the present embodiment, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical idea of the present embodiment, but to explain, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The scope of protection of this embodiment should be construed according to the claims below, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of rights of this embodiment.

10: pedal master unit 20: electric booster unit
30: housing 40: leg force forming unit
50: control unit 60: rod assembly

Claims (14)

A brake system configured to perform cooperative braking in which regenerative braking and hydraulic braking are performed together in a braking situation of a vehicle,
master cylinder;
a reaction disc having an elastic material disposed to press the master cylinder;
An electric booster unit including a motor piston disposed to pressurize at least a portion of the reaction disk and a screw shaft disposed to pressurize the motor piston, and configured to pressurize the master cylinder by adjusting displacement of the motor piston. (electric booster unit);
An operating rod arranged to adjust displacement according to the amount of depression of the brake pedal by the driver of the vehicle and an elastomer arranged such that one end contacts a portion of the operating rod and the other end contacts at least a portion of the electric booster unit A rod assembly including a (rod assembly); and
and a control unit configured to control the electric booster unit and perform control to brake the vehicle using at least one of the regenerative braking and the hydraulic braking. According to claim 1,
The elastic body,
The brake system, characterized in that in contact with the motor piston or the screw shaft of the configuration of the electric booster. According to claim 2,
The screw shaft,
A first shaft arranged to perform rotational motion and a second shaft arranged to convert the rotational motion of the first shaft into linear motion to press the motor piston,
The elastic body is the brake system, characterized in that in contact with the second shaft. According to claim 1,
When the control unit brakes the vehicle by performing at least the regenerative braking among the regenerative braking and the hydraulic braking,
The brake system according to claim 1 , wherein the control unit drives the electric booster unit to press the reaction disk when the regenerative braking is released. According to claim 1,
The brake system of claim 1 , wherein a central portion of the reaction disk is disposed to press the operating rod, and an outer portion of the reaction disk is disposed to press the motor piston. According to claim 5,
The brake system of claim 1 , wherein when the motor piston presses the reaction disk, a central portion of the reaction disk protrudes in a direction toward the operating rod according to the pressing degree. According to claim 6,
When the central part comes into contact with the operating rod by pressing the brake pedal by the driver of the vehicle, the pressure applied to the operating rod by the central part increases as the pressure applied to the reaction disk by the motor piston increases. The brake system, characterized in that the area in contact with the operating rod remains the same. According to claim 1,
When the hydraulic pressure in the master cylinder is maintained, if the difference between the displacement of the motor piston and the displacement of the operating rod is the same as the motor piston moves farther toward the reaction disk than the operating rod,
The brake system, characterized in that the magnitude of the leg force is maintained regardless of the degree to which the reaction disk presses the master cylinder. According to claim 1,
The elastic part,
A brake system comprising at least a spring among a spring and a damper. A control method of a brake system configured to perform cooperative braking in which regenerative braking and hydraulic braking are performed together in a braking situation of a vehicle,
(a) calculating a total required braking force for braking the vehicle based on a stroke of the brake pedal measured by a pedal travel sensor when the brake pedal is depressed;
(b) calculating a required regenerative braking force based on the total required braking force;
(c) driving a regenerative braking unit to have braking power equal to the requested regenerative braking power;
(d) determining whether the regenerative braking should be stopped;
(e) if it is determined that the regenerative braking should be stopped, calculating a hydraulic braking force required according to the stopping of the regenerative braking;
(f) calculating a required displacement of the motor piston according to the required hydraulic braking force;
(g) driving the electric booster to pressurize the reaction disk by moving the motor piston by the required displacement; and
(h) A process of performing control so that the size of the leg force is maintained as a whole by using an elastic body and the reaction disk disposed at one end in contact with the brake pedal and at the other end in contact with a part of the electric booster unit while the motor piston is moved by the required displacement
Brake system control method comprising a. According to claim 10,
The motor piston is a brake system control method, characterized in that made of an elastic material. According to claim 10,
The brake system control method according to claim 1 , wherein an outer portion of the reaction disk is disposed so that the motor piston presses the reaction disk. According to claim 10,
In the process (g),
The brake system control method according to claim 1 , wherein the magnitude of reaction force formed when the motor piston presses the reaction disk is constant. According to claim 10,
In the process (f),
The brake system control method according to claim 1 , wherein the required displacement is calculated in consideration of whether the reaction disk and the operating rod are in contact.

Images