Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided to fully convey the spirit of the present invention to a person having ordinary skill in the art to which the present invention belongs. The present invention is not limited to the embodiments shown herein but may be embodied in other forms. For the sake of clarity, the drawings are not drawn to scale, and the size of the elements may be slightly exaggerated to facilitate understanding.
Fig. 1 is a hydraulic circuit diagram showing the non-synchronized state of the electromagnetic brake system 1 according to the embodiment of the present invention.
1, the electronic brake system 1 typically includes a master cylinder 20 for generating hydraulic pressure, a reservoir 30 coupled to the top of the master cylinder 20 for storing oil, a brake pedal (not shown) An input rod 12 which pressurizes the master cylinder 20 in accordance with the pressing force of the brake pedal 10 and a wheel cylinder 40 which transmits hydraulic pressure to brake the wheels RR, RL, FR and FL, A pedal displacement sensor 11 for detecting the displacement of the brake pedal 10 and a simulation device 50 for providing a reaction force in response to the power of the brake pedal 10.
The master cylinder 20 may be configured to include at least one chamber to generate hydraulic pressure. In one example, the master cylinder 20 is configured to have two chambers, each chamber being provided with a first piston 21a and a second piston 22a, the first piston 21a being connected to the input rod 12 ). The master cylinder 20 may form first and second hydraulic ports 24a and 24b, respectively, through which fluid pressure is discharged from the two chambers.
On the other hand, the master cylinder 20 has two chambers to ensure safety in case of failure. For example, one of the two chambers may be connected to the right front wheel FR and the left rear wheel RL of the vehicle, and the other chamber may be connected to the left front wheel FL and the right rear wheel RR. Thus, by independently configuring the two chambers, it is possible to braking the vehicle even if one of the chambers fails.
Or one of the two chambers may be connected to the two front wheels FR and FL, and the other chamber may be connected to the two rear wheels RR and RL, as shown in the figure. In addition, one of the two chambers may be connected to the left front wheel FL and the left rear wheel RL, and one chamber may be connected to the right rear wheel RR and the right front wheel FR. That is, the positions of the wheels connected to the chambers of the master cylinder 20 can be variously configured.
A first spring 21b is provided between the first piston 21a and the second piston 22a of the master cylinder 20 and a second spring 21b is provided between the end of the master cylinder 20 and the second piston 22a. 2 spring 22b may be provided.
The first spring 21b and the second spring 22b are respectively provided in the two chambers and as the displacement of the brake pedal 10 changes, the first piston 21a and the second piston 22a are compressed, The elastic force is stored in the spring 21b and the second spring 22b. When the pushing force of the first piston 21a becomes smaller than the elastic force, the first and second pistons 21a and 22a are returned to the original state by using the elastic force stored in the first spring 21b and the second spring 22b .
On the other hand, the input rod 12 for pressing the first piston 21a of the master cylinder 20 can be brought into contact with the first piston 21a in close contact with each other. That is, a gap between the master cylinder 20 and the input rod 12 may not exist. Therefore, when the brake pedal 10 is depressed, the master cylinder 20 can be directly pressed without a pedal invalid stroke section.
The simulation apparatus 50 may be connected to a first backup passage 251 to be described later to provide a reaction force according to the pressing force of the brake pedal 10. The reaction force is provided as much as the driver's compensation is compensated for, so that the driver can finely adjust the braking force as intended.
1, the simulation apparatus 50 includes a simulation chamber 51 configured to store oil flowing out from the first hydraulic port 24a of the master cylinder 20 and a reaction force piston (not shown) provided in the simulation chamber 51 And a simulator valve 54 connected to the pedal simulator and the rear end of the simulation chamber 51. The simulator valve 54 is connected to the rear end of the simulation chamber 51,
The reaction force piston 52 and the reaction force spring 53 are installed so as to have a certain range of displacement in the simulation chamber 51 by the oil introduced into the simulation chamber 51.
On the other hand, the reaction force spring 53 shown in the drawings is only one embodiment capable of providing an elastic force to the reaction force piston 52, and may include various embodiments capable of storing elastic force by shape deformation. For example, it includes various members capable of storing an elastic force by being made of a material such as rubber or having a coil or a plate shape.
The simulator valve 54 may be provided in a flow path connecting the rear end of the simulation chamber 51 and the reservoir 30. [ The front end of the simulation chamber 51 is connected to the master cylinder 20 and the rear end of the simulation chamber 51 can be connected to the reservoir 30 through the simulator valve 54. Therefore, even when the reaction force piston 52 returns, oil in the reservoir 30 flows through the simulator valve 54, so that the entire interior of the simulation chamber 51 can be filled with the oil.
In the meantime, several reservoirs 30 are shown in the figure, and each reservoir 30 uses the same reference numerals. However, these reservoirs may be provided with the same parts or may be provided with different parts. For example, the reservoir 30 connected to the simulation apparatus 50 can store the oil separately from the reservoir 30 connected to the master cylinder 20, or to the reservoir 30 connected to the master cylinder 20 It can be a repository.
On the other hand, the simulator valve 54 may be constituted by a normally closed type solenoid valve that keeps the normally closed state. The simulator valve 54 can be opened when the driver applies pressure to the brake pedal 10 to deliver the brake fluid between the simulation chamber 51 and the reservoir 30. [
Further, a simulator check valve 55 may be provided between the pedal simulator and the reservoir 30 so as to be connected to the simulator valve 54 in parallel. The simulator check valve 55 allows the oil of the reservoir 30 to flow into the simulation chamber 51 while the oil of the simulation chamber 51 flows into the reservoir 30 through the flow path in which the check valve 55 is installed You can block things. A quick return of the pedal simulator pressure can be ensured since the oil can be supplied into the simulation chamber 51 through the simulator check valve 55 when the brake pedal 10 is depressed.
The simulating chamber 51 which pushes the reaction force spring 53 while compressing the reaction force piston 52 of the pedal simulator when the driver applies the pressing force to the brake pedal 10 will be described. Is delivered to the reservoir 30 through the simulator valve 54, in which the driver is provided with a feeling of a pedal. When the driver releases his / her foot to the brake pedal 10, the reaction force spring 52 pushes the reaction force piston 52 to return the reaction force piston 52 to its original state, and the oil of the reservoir 30 is returned to the simulator valve 54 may flow into the simulation chamber 51 through the flow path where the check valve 55 and the check valve 55 are installed, so that the oil can be filled in the simulation chamber 51.
Since the inside of the simulation chamber 51 is filled with oil at all times, friction of the reaction force piston 52 is minimized during operation of the simulation apparatus 50 to improve the durability of the simulation apparatus 50, Can be blocked.
An electronic brake system 1 according to an embodiment of the present invention includes a hydraulic pressure supply device 100 (hereinafter, referred to as " brake ") that receives mechanical signals of a driver's braking intent from a pedal displacement sensor 11 that senses displacement of a brake pedal 10, And first and second hydraulic circuits 201 and 202 for controlling the flow of hydraulic pressure transmitted to the wheel cylinders 40 provided in the two wheels RR, RL, FR and FL, respectively, A first cut valve 261 provided in a first backup passage 251 for connecting the first hydraulic pressure port 24a and the first hydraulic circuit 201 to control the flow of hydraulic pressure, A second cut valve 262 provided on a second backup passage 252 connecting the hydraulic port 24b and the second hydraulic circuit 202 to control the flow of the hydraulic pressure, An electronic device for controlling the supply device 100 and the valves 54, 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 231, 232, 241, (ECU) (not shown).
The hydraulic pressure supply device 100 includes a hydraulic pressure supply unit 110 for supplying oil pressure to the wheel cylinder 40, a motor 120 for generating a rotational force by an electrical signal of the pedal displacement sensor 11, And a power converting unit 130 that converts the rotational motion of the motor 120 into a rectilinear motion and transmits the rectilinear motion to the hydraulic pressure providing unit 110. Or the hydraulic pressure providing unit 110 may be operated not by the driving force supplied from the motor 120 but by the pressure provided by the high pressure accumulator.
The hydraulic pressure providing unit 110 includes a cylinder block 111 in which a pressure chamber to be stored with oil is formed, a hydraulic piston 114 housed in the cylinder block 111, a hydraulic piston 114 and a cylinder block 111 And a sealing member 115 which is provided between the pressure chambers and seals the pressure chambers.
The pressure chamber includes a first pressure chamber 112 positioned rearward (backward direction, rightward in the figure) of the hydraulic piston 114 and a second pressure chamber 112 positioned forward (forward direction, leftward in the drawing) of the hydraulic piston 114 And may include a second pressure chamber 113. That is, the first pressure chamber 112 is divided by the cylinder block 111 and the rear end of the hydraulic piston 114. The volume of the first pressure chamber 112 is changed according to the movement of the hydraulic piston 114, Is divided by the front end of the cylinder block 111 and the hydraulic piston 114 and is provided such that the volume thereof changes according to the movement of the hydraulic piston 114. [
The first pressure chamber 112 is connected to the first hydraulic fluid passage 211 through the first communication hole 111a formed on the rear side of the cylinder block 111 and the second pressure chamber 113 is connected to the cylinder block 111 111 through a second communication hole 111b formed on the front side of the second hydraulic oil path 212. [ The first hydraulic oil path 211 connects the hydraulic pressure providing unit 110 to the first hydraulic circuit 201 and the second hydraulic fluid path 212 connects the hydraulic pressure providing unit 110 and the second hydraulic circuit 202 do.
The sealing member 115 seals between the first pressure chamber 112 and the second pressure chamber 113. That is, the hydraulic pressure or the negative pressure of the first pressure chamber 112 generated by the forward or backward movement of the hydraulic piston 114 is blocked by the sealing member 115 and is not leaked to the second pressure chamber 113, Lt; RTI ID = 0.0 > 211 < / RTI >
The pressure chamber is connected to the reservoir 30 by the dump channels 116 and 117 and can receive and store oil from the reservoir 30 or transfer the oil in the pressure chamber to the reservoir 30. The dump passage includes a first dump passage 116 branched from the first hydraulic oil passage 211 and connected to the reservoir 30 and a second dump passage 116 branched from the second hydraulic oil passage 212 and connected to the reservoir 30, 2 dump flow path 117. In the embodiment shown in FIG.
In addition, the electronic brake system 1 according to the embodiment of the present invention may further include dump valves 231 and 232 for controlling the opening and closing of the dump channels 116 and 117. The dump valves 231 and 232 may be provided as solenoid valves of a normal closed type (Norm Cloesd type) which are normally closed and operated to open the valves when an open signal is received.
The dump valve includes a first dump valve 231 installed in the first dump passage 116 for controlling the oil flow and a second dump valve 232 installed in the second dump passage 117 for controlling the oil flow do. The dump passages 116 and 117 in which the dump valves 231 and 232 are installed are connected to the pressure chambers 112 and 113 and the hydraulic oil passages 211 and 212 of the hydraulic pressure supply device 100, When the pressure is higher than the set target pressure value according to the power, it can be controlled to follow the target pressure value.
Further, the hydraulic pressure providing unit 110 of the electromagnetic brake system 1 according to the embodiment of the present invention can operate in a double-acting manner. The hydraulic pressure generated in the second pressure chamber 113 while the hydraulic piston 114 advances is transmitted to the second hydraulic circuit 202 to be supplied to the wheel cylinders 40 ). ≪ / RTI > The negative pressure generated in the first pressure chamber 112 while the hydraulic piston 114 advances is transmitted to the first hydraulic circuit 201 and is transmitted to the wheel cylinders 40 ). ≪ / RTI >
The hydraulic pressure generated in the first pressure chamber 112 while the hydraulic pressure piston 114 moves backward is transmitted to the first hydraulic circuit 201 and is transmitted to the wheel cylinders 40 ). ≪ / RTI > The negative pressure generated in the second pressure chamber 113 while the hydraulic piston 114 is reversed is transmitted to the second hydraulic circuit 202 to be supplied to the wheel cylinders 40 ). ≪ / RTI >
The motor 120 is a device for generating a rotational force by a signal output from an electronic control unit (ECU) (not shown), and can generate a rotational force in a forward or reverse direction. The rotational angular velocity and rotational angle of the motor 120 can be precisely controlled. Since the motor 120 is a well-known technology, its detailed description will be omitted.
On the other hand, the electronic control unit includes valves (54, 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 231, 232, 241, and 242, respectively. The operation in which a plurality of valves are controlled according to the displacement of the brake pedal 10 will be described later.
The driving force of the motor 120 causes the displacement of the hydraulic piston 114 through the power conversion unit 130 and the hydraulic pressure generated by the sliding movement of the hydraulic piston 114 in the pressure chamber is transmitted to the first and second hydraulic oil RL, FR, and FL through wheel cylinders 211 and 212, respectively.
The power converting unit 130 is a device for converting the rotational force into a linear motion. The power converting unit 130 may include a worm shaft 131, a worm wheel 132, and a drive shaft 133, for example.
The worm shaft 131 may be formed integrally with the rotation shaft of the motor 120, and is formed with a worm on the outer circumferential surface thereof to be engaged with the worm wheel 132 to rotate the worm wheel 132. The worm wheel 132 is connected to the drive shaft 133 to linearly move the drive shaft 133. The drive shaft 133 is connected to the hydraulic piston 114 to slide the hydraulic piston 114 in the cylinder block 111 .
A signal sensed by the pedal displacement sensor 11 is transmitted to an electronic control unit (ECU) (not shown) while a displacement occurs in the brake pedal 10, The worm shaft 131 is rotated in one direction. The rotational force of the warm shaft 131 is transmitted to the drive shaft 133 via the worm wheel 132 and the hydraulic piston 114 connected to the drive shaft 133 moves forward to generate a hydraulic pressure in the pressure chamber.
On the other hand, when the brake pedal 10 is depressed, the electronic control unit drives the motor 120 in the opposite direction so that the worm shaft 131 rotates in the opposite direction. The worm wheel 132 also rotates in the opposite direction and the hydraulic piston 114 connected to the drive shaft 133 returns.
A signal sensed by the pedal displacement sensor 11 is transmitted to an electronic control unit (ECU) (not shown) while a displacement occurs in the brake pedal 10 and the electronic control unit drives the motor 120 in one direction, Thereby rotating the shaft 131 in one direction. The rotational force of the worm shaft 131 is transmitted to the drive shaft 133 via the worm wheel 132 and the hydraulic pressure piston 114 connected to the drive shaft 133 moves forward to generate a hydraulic pressure in the second pressure chamber 113.
On the other hand, when the brake pedal 10 is depressed, the electronic control unit drives the motor 120 in the opposite direction so that the worm shaft 131 rotates in the opposite direction. Accordingly, the worm wheel 132 also rotates in the opposite direction and generates a negative pressure in the second pressure chamber 113 while the hydraulic piston 114 connected to the drive shaft 133 returns (moves backward).
On the other hand, the hydraulic pressure and the negative pressure can be generated in the opposite direction. That is, when a displacement occurs in the brake pedal 10, a signal sensed by the pedal displacement sensor 11 is transmitted to an electronic control unit (ECU) (not shown), and the electronic control unit drives the motor 120 in the opposite direction Thereby rotating the worm shaft 131 in the opposite direction. The rotational force of the warm shaft 131 is transmitted to the drive shaft 133 via the worm wheel 132 and the hydraulic pressure piston 114 connected to the drive shaft 133 moves backward to generate the hydraulic pressure in the first pressure chamber 112.
On the other hand, when the pressing force is removed from the brake pedal 10, the electronic control unit drives the motor 120 in one direction so that the worm shaft 131 rotates in one direction. Accordingly, the worm wheel 132 also rotates in the opposite direction and generates a negative pressure in the first pressure chamber 112 while the hydraulic piston 114 connected to the drive shaft 133 returns (advances).
The hydraulic pressure supply device 100 transfers the hydraulic pressure to the wheel cylinder 40 or sucks the hydraulic pressure to the reservoir 30 according to the rotational direction of the rotational force generated from the motor 120.
On the other hand, when the motor 120 rotates in one direction, a hydraulic pressure may be generated in the second pressure chamber 113, or a negative pressure may be generated in the first pressure chamber 112. The hydraulic pressure may be used for braking, Whether to release the braking operation can be determined by controlling the valves 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 231, 232, 241 and 242. This will be described later in detail.
Although not shown in the drawing, the power conversion unit 130 may be formed of a ball screw nut assembly. For example, a screw formed integrally with the rotating shaft of the motor 120 or connected to rotate as the rotating shaft of the motor 120, and a ball nut screwed with the screw in a limited rotation state and linearly moving according to the rotation of the screw . The hydraulic piston 114 is connected to the ball nut of the power converting unit 130 to press the pressure chamber by linear motion of the ball nut. The structure of such a ball screw nut assembly is a device that converts rotational motion into linear motion and is a well-known technique that has been well known in the art, and thus a detailed description thereof will be omitted.
It should be understood that the power converting unit 130 according to the embodiment of the present invention can adopt any structure as long as it can convert rotational motion into linear motion in addition to the structure of the ball screw nut assembly.
The electromagnetic brake system 1 according to the embodiment of the present invention may also include first and second backup oil passages (not shown) capable of supplying the oil discharged from the master cylinder 20 directly to the wheel cylinder 40 when the oil brake system is operating abnormally 251, and 252, respectively.
A first cut valve 261 for controlling the flow of oil is provided in the first backup passage 251 and a second cut valve 262 for controlling the flow of oil is provided in the second backup passage 252 have. The first backup hydraulic passage 251 connects the first hydraulic pressure port 24a and the first hydraulic pressure circuit 201 and the second backup hydraulic passage 252 connects the second hydraulic pressure port 25b and the second hydraulic circuit 202 can be connected.
The first and second cut valves 261 and 262 may be provided with a normally open type solenoid valve that is opened in a normal state and operates to close the valve when receiving a close signal from the electronic control unit have.
Next, the hydraulic control unit 200 according to an embodiment of the present invention will be described with reference to FIG.
The hydraulic control unit 200 may include a first hydraulic circuit 201 and a second hydraulic circuit 202, each of which receives hydraulic pressure and controls two wheels, respectively. For example, the first hydraulic circuit 201 controls the right front wheel FR and the left rear wheel RL, and the second hydraulic circuit 202 can control the left front wheel FL and the right rear wheel RR . The wheel cylinders 40 are provided on the respective wheels FR, FL, RR, and RL to supply hydraulic pressure to perform braking.
The first hydraulic circuit 201 is connected to the first hydraulic oil path 211 and is supplied with hydraulic pressure from the hydraulic pressure supply device 100. The first hydraulic oil path 211 is connected to the right front wheel FR and the left rear wheel RL It branches to two connected channels. Similarly, the second hydraulic circuit 202 is connected to the second hydraulic oil path 212 to receive the hydraulic pressure from the hydraulic pressure supply device 100, and the second hydraulic oil path 212 is connected to the left front wheel FL and the right rear wheel RR ). ≪ / RTI >
The hydraulic circuits 201 and 202 may have a plurality of inlet valves 221 (221a, 221b, 221c and 221d) to control the flow of hydraulic pressure. For example, the first hydraulic circuit 201 may be provided with two inlet valves 221a and 221b connected to the first hydraulic oil path 211 and controlling the hydraulic pressures transmitted to the two wheel cylinders 40, respectively . The second hydraulic circuit 202 may be provided with two inlet valves 221c and 221d which are connected to the second hydraulic fluid path 212 and control hydraulic pressures transmitted to the wheel cylinders 40, respectively.
The inlet valve 221 is disposed on the upstream side of the wheel cylinder 40 and is provided with a solenoid valve of a normally closed type which is normally closed and operates to open the valve when receiving an open signal from the electronic control unit .
Further, the hydraulic control unit 200 may further include a plurality of outlet valves 222 (222a, 222b, 222c, 222d) connected to the reservoir 30 to improve the performance at the time of braking release. The outlet valve 222 is connected to the wheel cylinder 40 to control the hydraulic pressure from the wheels RR, RL, FR and FL, respectively. That is, the outlet valve 222 senses the braking pressure of each of the wheels RR, RL, FR and FL and is selectively opened to control the pressure when the pressure reduction braking is required.
And the outlet valve 222 may be provided with a solenoid valve of a normal closed type which is normally closed and operates to open the valve when receiving an open signal from the electronic control unit.
Further, the hydraulic control unit 200 can be connected to the backup channels 251 and 252. The first hydraulic circuit 201 is connected to the first backup hydraulic line 251 to receive the hydraulic pressure from the master cylinder 20 and the second hydraulic circuit 202 is connected to the second backup hydraulic line 252 The hydraulic pressure can be supplied from the master cylinder 20.
At this time, the first backup oil passage 251 can join the first hydraulic circuit 201 downstream of the first inlet valve 221a. Similarly, the second backup oil passage 252 can join the second hydraulic circuit 202 downstream of the fourth inlet valve 221d. Accordingly, when the first and second cut valves 261 and 262 are closed and the plurality of inlet valves 221a, 221b, 221c, and 221d are opened, the hydraulic pressure provided by the hydraulic pressure supply device 100 is switched between the first and second The first cut valve 261 and the second cut valve 262 are opened and the plurality of inlet valves 221a, 221b, 221c and 221d are closed to the wheel cylinders 40 through the hydraulic oil passages 211 and 212, The hydraulic pressure supplied from the master cylinder 20 can be supplied to the wheel cylinder 40 through the first and second backup oil channels 251 and 252. [
The hydraulic control unit 200 may further include balance valves 241 and 242 connecting the first hydraulic circuit 201 and the second hydraulic circuit 202. [ The balance valve includes a first balance valve 241 for connecting one of two flow paths in which the first hydraulic fluid path 211 is branched and another flow path of the two flow paths in which the second hydraulic fluid path 212 is branched, And a second balance valve 242 connecting the remaining two flow paths.
The first hydraulic oil passage 211 is branched in the middle and is connected to the right front wheel FR and the left rear wheel RL respectively and the second hydraulic oil passage 212 is branched on the way to connect the left front wheel FL and the right rear wheel RR, Respectively. For example, the first balance valve 241 connects the flow path connected to the right front wheel FR and the flow path connected to the left front wheel FL, and the second balance valve 242 connects the right rear wheel RR And the oil passage connected to the left rear wheel RL can be connected to each other.
The balance valves 241 and 242 are provided in a flow path connecting the first hydraulic circuit 201 and the second hydraulic circuit 202 to connect or disconnect the first and second hydraulic circuits 201 and 202 Role.
The first and second balance valves 241 and 242 may be provided as normally open type solenoid valves that normally open and operate to close the valve when receiving a close signal from the electronic control unit .
Reference numeral " PS11 " is a first hydraulic oil pressure sensor for sensing the hydraulic pressure of the first hydraulic circuit 201, "PS12" is a second hydraulic oil for sensing the hydraulic pressure of the second hydraulic circuit 202, Quot; PS2 "is a back-up hydraulic pressure sensor for measuring the oil pressure of the master cylinder 20. [ And "MPS" is a motor control sensor for controlling the rotation angle of the motor 120 or the current of the motor.
Hereinafter, the operation of the electronic brake system 1 according to the embodiment of the present invention will be described in detail.
2 and 3 illustrate a state in which the electromagnetic brake system 1 according to the embodiment of the present invention is normally braked. Fig. 2 shows a situation in which the hydraulic piston 114 provides a braking pressure while advancing, 3 is a hydraulic circuit diagram showing a situation in which the hydraulic pressure piston 114 provides a braking pressure while moving backward.
When the braking by the driver is started, the amount of brake demand of the driver can be sensed through the pedal displacement sensor 11 through information such as the pressure of the brake pedal 10 depressed by the driver. An electronic control unit (not shown) receives the electrical signal output from the pedal displacement sensor 11 and drives the motor 120.
The electronic control unit includes a backup hydraulic pressure sensor PS2 provided at the outlet side of the master cylinder 20 and first and second hydraulic oil pressure sensors PS11 and PS12 provided at the first and second hydraulic circuits 201 and 202, The magnitude of the regenerative braking amount is input through the regenerative braking amount controller PS12 and the size of the frictional braking amount is calculated according to the difference between the demand braking amount and the regenerating braking amount of the driver.
2, when the driver depresses the brake pedal 10 at the beginning of braking, the motor 120 is operated to rotate in one direction, and the rotational force of the motor 120 is transmitted to the hydraulic pressure providing unit 130 by the power transmitting unit 130. [ And the hydraulic pressure piston 114 of the hydraulic pressure providing unit 110 advances to generate the hydraulic pressure in the second pressure chamber 113. The hydraulic pressure discharged from the hydraulic pressure providing unit 110 is transmitted to the wheel cylinders 40 provided on the four wheels through the first hydraulic circuit 201 and the second hydraulic circuit 202 to generate the braking force.
Specifically, the hydraulic pressure provided in the second pressure chamber 113 is transmitted to the wheel cylinder 40 provided on the two wheels RR and FL through the second hydraulic oil passage 212 connected to the second communication hole 111b. Lt; / RTI > At this time, the third and fourth inlet valves 221c and 221d, which are respectively installed in the two flow paths branched by the second hydraulic oil path 212, are switched to the open state. The third and fourth outlet valves 222c and 222d provided in the flow paths branched respectively from the two flow paths branched from the second hydraulic fluid path 212 and the second dump valve 232 are kept closed to prevent the liquid pressure from leaking to the reservoir 30.
When the pressure transmitted to the first and second hydraulic circuits 201 and 202 is measured to be higher than the target pressure value corresponding to the leg power of the brake pedal 10, the second dump valve 232 is opened, As shown in FIG.
Since the first balance valve 241 and the second balance valve 242 are in an open state, the hydraulic pressure of the second hydraulic circuit 202 can be transmitted to the first hydraulic circuit 201. Therefore, the hydraulic pressure is also transmitted to the wheel cylinders 40 provided on the remaining two wheels FR and RL.
Specifically, the hydraulic pressure that branches off from the second hydraulic oil path 212 and moves to the left front wheel FL is transmitted to the wheel cylinder 40 provided on the right front wheel FR through the first balance valve 241, The hydraulic pressure that branches from the second hydraulic oil passage 212 to the right rear wheel RR is transmitted to the wheel cylinder 40 provided on the left rear wheel RL through the second balance valve 242. [
At this time, the first dump valve 231 provided in the first dump passage 116 is switched to the open state. The oil of the reservoir 30 flows into the first pressure chamber 112 through the first dump passage 116 as the hydraulic pressure piston 114 advances and the volume of the first pressure chamber 112 becomes larger. In addition, the first inlet valve 222a and the second inlet valve 222b of the first hydraulic circuit 201 are kept closed.
The first and second hydraulic oil passages 251 and 252 connected to the first and second hydraulic ports 24a and 24b of the master cylinder 20 generate hydraulic pressure in the hydraulic pressure supply device 100, The second cut valves 261 and 262 are closed so that the hydraulic pressure discharged from the master cylinder 20 is not transmitted to the wheel cylinder 40.
The pressure generated in response to the pressing force of the brake pedal 10 in accordance with the pressure of the master cylinder 20 is transmitted to the simulation apparatus 50 connected to the master cylinder 20. [ At this time, the normally closed simulator valve 54 disposed at the rear end of the simulation chamber 51 is opened, and the oil filled in the simulation chamber 51 through the simulator valve 54 is transferred to the reservoir 30. Further, a pressure corresponding to the load of the reaction force spring 53, in which the reaction force piston 52 is moved and which supports the reaction force piston 52, is formed in the simulation chamber 51 to provide an appropriate pedal feeling to the driver.
2, the braking force can be generated in the wheel cylinder 40 even when the hydraulic piston 114 moves in the opposite direction, that is, when the hydraulic piston 114 moves backward.
3, when the driver depresses the brake pedal 10 at the beginning of braking, the motor 120 is operated to rotate in the opposite direction, and the rotational force of the motor 120 is transmitted to the hydraulic pressure supply unit 130 by the power transmission unit 130. [ And the hydraulic pressure piston 114 of the hydraulic pressure providing unit 110 moves backward to generate the hydraulic pressure in the first pressure chamber 112. [ The hydraulic pressure discharged from the hydraulic pressure providing unit 110 is transmitted to the wheel cylinders 40 provided on the four wheels through the first hydraulic circuit 201 and the second hydraulic circuit 202 to generate the braking force.
Specifically, the hydraulic pressure provided in the first pressure chamber 112 is transmitted to the wheel cylinder 40 provided on the two wheels FR and RL through the first hydraulic oil path 211 connected to the first communication hole 111a. Lt; / RTI > At this time, the first and second inlet valves 221a and 221b installed in the two flow paths branched from the first hydraulic oil path 211 are switched to the open state. The first and second outlet valves 222a and 222b provided in the flow paths branched respectively from the two flow paths branched from the first hydraulic fluid path 211 and the first dump valves 222a and 222b provided in the first dump flow path 116 231 are kept closed to prevent the liquid pressure from leaking to the reservoir 30.
When the pressure transmitted to the first and second hydraulic circuits 201 and 202 is measured to be higher than the target pressure value corresponding to the leg power of the brake pedal 10, the first dump valve 231 is opened, As shown in FIG.
Since the first balance valve 241 and the second balance valve 242 are in the open state, the hydraulic pressure of the first hydraulic circuit 201 can be transmitted to the second hydraulic circuit 202. Therefore, the hydraulic pressure is also transmitted to the wheel cylinders 40 provided on the remaining two wheels FR and RL.
Specifically, the hydraulic pressure that is branched from the first hydraulic oil path 211 and moves to the right front wheel FR is transmitted to the wheel cylinder 40 provided in the left front wheel FL through the first balance valve 241, The hydraulic pressure that branches from the first hydraulic oil passage 211 and moves to the left rear wheel RL is transmitted to the wheel cylinder 40 provided on the right rear wheel RR through the second balance valve 242. [
At this time, the second dump valve 232 installed in the second dump passage 117 is switched to the opened state. The oil of the reservoir 30 flows into the second pressure chamber 113 and is filled through the second dump passage 117 as the hydraulic piston 114 moves backward and the volume of the second pressure chamber 113 increases. In addition, the third inlet valve 222c and the fourth inlet valve 222d of the second hydraulic circuit 202 are kept closed.
Next, the case of releasing the braking force in the braking state in the normal operation of the electromagnetic brake system 1 according to the embodiment of the present invention will be described.
4 and 5 show a state in which the electromagnetic brake system 1 according to the embodiment of the present invention is normally released. Fig. 4 shows a state in which the hydraulic pressure piston 114 is released and the braking pressure is released, 5 is a hydraulic circuit diagram showing a situation in which the hydraulic pressure piston 114 is advanced and the braking pressure is released.
4, when the pedal force applied to the brake pedal 10 is released, the motor 120 generates a rotational force in the opposite direction to deliver the rotational force to the power converting unit 130, The shaft 131, the worm wheel 132 and the drive shaft 133 are rotated in the opposite direction to rotate the hydraulic piston 114 back to its original position to release the pressure in the second pressure chamber 113 . The hydraulic pressure providing unit 110 receives the hydraulic pressure discharged from the wheel cylinder 40 through the first and second hydraulic circuits 201 and 202 and transfers the hydraulic pressure to the second pressure chamber 113.
The negative pressure generated in the second pressure chamber 113 is transmitted to the wheel cylinder 40 provided on the two wheels RR and FL through the second hydraulic fluid passage 212 connected to the second communication hole 111b. Lt; / RTI > At this time, the third and fourth inlet valves 221c and 221d, which are respectively installed in the two flow paths branched by the second hydraulic oil path 212, are switched to the open state. The third and fourth outlet valves 222c and 222d provided in the flow paths branched respectively from the two flow paths branched from the second hydraulic fluid path 212 and the second dump valve 232 are kept closed to prevent the oil of the reservoir 30 from being introduced.
When the negative pressure transmitted to the first and second hydraulic circuits 201 and 202 is measured to be higher than the target pressure release value corresponding to the release amount of the brake pedal 10, the second dump valve 232 is opened, It is possible to control to follow the pressure value.
Since the first balance valve 241 and the second balance valve 242 are in an open state, the negative pressure of the second hydraulic circuit 202 can be transmitted to the first hydraulic circuit 201. Therefore, the pressure of the wheel cylinder 40 provided on the remaining two wheels FR and RL can be released.
Specifically, the negative pressure that branches off from the second hydraulic fluid path 212 and moves to the left front wheel FL is transmitted to the wheel cylinder 40 provided on the right front wheel FR through the first balance valve 241, The negative pressure which branches from the second hydraulic oil passage 212 to the right rear wheel RR is transmitted to the wheel cylinder 40 provided on the left rear wheel RL through the second balance valve 242. [
At this time, the first dump valve 231 provided in the first dump passage 116 is switched to the open state. The oil in the first pressure chamber 112 is transferred to the reservoir 30 through the first dump passage 116 as the hydraulic piston 114 moves backward and the volume of the first pressure chamber 112 decreases. In addition, the first inlet valve 222a and the second inlet valve 222b of the first hydraulic circuit 201 are kept closed.
The first and second hydraulic oil passages 251 and 252 connected to the first and second hydraulic ports 24a and 24b of the master cylinder 20 generate hydraulic pressure in the hydraulic pressure supply device 100, The second cut valves 261 and 262 are closed so that the negative pressure sucked by the master cylinder 20 is not transmitted to the wheel cylinder 40. [
Unlike Fig. 4, the braking force of the wheel cylinder 40 can be released even when the hydraulic piston 114 moves in the opposite direction, i.e., advances.
5, when the pedal force applied to the brake pedal 10 is released, the motor 120 generates a rotational force in the opposite direction to deliver the rotational force to the power converting unit 130, The shaft 131, the worm wheel 132 and the drive shaft 133 are rotated in opposite directions to advance the hydraulic piston 114 to the original position, thereby releasing the pressure in the first pressure chamber 112 or reducing the negative pressure . The hydraulic pressure providing unit 110 receives the hydraulic pressure discharged from the wheel cylinder 40 through the first and second hydraulic circuits 201 and 202 and transfers the hydraulic pressure to the first pressure chamber 112.
The negative pressure generated in the first pressure chamber 112 is transmitted to the wheel cylinder 40 provided on the two wheels FR and RL through the first hydraulic oil path 211 connected to the first communication hole 111a. Lt; / RTI > At this time, the first and second inlet valves 221a and 221b installed in the two flow paths branched from the first hydraulic oil path 211 are switched to the open state. The first and second outlet valves 222a and 222b provided in the flow paths branched respectively from the two flow paths branched from the first hydraulic fluid path 211 and the first dump valves 222a and 222b provided in the first dump flow path 116 231 are kept closed to prevent the oil of the reservoir 30 from being introduced.
When the negative pressure transmitted to the first and second hydraulic circuits 201 and 202 is measured to be higher than the target pressure release value corresponding to the release amount of the brake pedal 10, the first dump valve 231 is opened, It is possible to control to follow the pressure value.
Since the first balance valve 241 and the second balance valve 242 are in the open state, the negative pressure of the first hydraulic circuit 201 can be transmitted to the second hydraulic circuit 202. Therefore, the pressure of the wheel cylinder 40 provided on the remaining two wheels FL and RR can be released.
Specifically, the negative pressure that is branched from the first hydraulic fluid path 211 and moves to the right front wheel FR is transmitted to the wheel cylinder 40 provided in the left front wheel FL through the first balance valve 241, The negative pressure that branches from the first hydraulic oil passage 211 and moves to the left rear wheel RL is transmitted to the wheel cylinder 40 provided on the right rear wheel RR through the second balance valve 242. [
At this time, the second dump valve 232 installed in the second dump passage 117 is switched to the opened state. The oil in the second pressure chamber 113 is transferred to the reservoir 30 through the second dump passage 117 as the hydraulic piston 114 advances and the volume of the second pressure chamber 113 becomes smaller. In addition, the third inlet valve 222c and the fourth inlet valve 222d of the second hydraulic circuit 202 are kept closed.
The simulation apparatus 50 is configured such that the oil in the simulation chamber 51 is transferred to the master cylinder 20 as the reaction force piston 52 is returned to the home position by the elastic force of the reaction force spring 53, A quick return of the pedal simulator pressure is ensured by refilling the oil into the simulation chamber 51 through the connected simulator valve 54 and simulator check valve 55.
The electronic brake system 1 according to the embodiment of the present invention is also applicable to the wheel cylinders 40 provided in the respective wheels RR, RL, FR, FL of the two hydraulic circuits 201, The control range can be specified and controlled by controlling the valves 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 241, and 242 provided in the hydraulic control unit 200.
6 and 7 show a state in which the electromagnetic brake system 1 according to the embodiment of the present invention is actuated by the ABS. Fig. 6 shows a state in which the hydraulic piston 114 is selectively braked while advancing, Is a hydraulic circuit diagram showing a situation in which the hydraulic pressure piston 114 brakes selectively while being reversed.
6 and 7 show a state in which only the corresponding wheel cylinder 40 is to be braked during ABS operation. Fig. 6 shows a state in which only one wheel is braked. Fig. 7 shows a state in which only one wheel is braked. RL, FR) is shown.
When the motor 120 is operated according to the urging force of the brake pedal 10, the rotational force of the motor 120 is transmitted to the hydraulic pressure providing unit 110 through the power transmitting portion 130, thereby generating hydraulic pressure. At this time, the first and second cut valves 261 and 262 are closed so that the hydraulic pressure discharged from the master cylinder 20 is not transmitted to the wheel cylinder 40.
6, hydraulic pressure is generated in the second pressure chamber 113 while the hydraulic piston 114 advances, and the fourth inlet valve 221d is switched to the open state and is transmitted through the second hydraulic oil path 212 The wheel cylinder 40, which is located at the right rear wheel RR, is operated to generate the braking force.
At this time, the first to third inlet valves 221a, 221b and 221c, the first to fourth outlet valves 222a, 222b, 222c and 222d and the second dump valve 232 are closed . The second balance valve 242 is switched to the closed state and the hydraulic pressure of the second hydraulic circuit 202 is not transmitted to the first hydraulic circuit 201. Then, the first dump valve 231 is switched to the open state to fill the first pressure chamber 112 from the reservoir 30 with oil.
7, when the hydraulic pressure piston 114 is moved backward, a hydraulic pressure is generated in the first pressure chamber 112 and the first and second inlet valves 221a and 221b are switched to the open state, 212 to generate a braking force by operating the wheel cylinders 40 in which the hydraulic pressure is transmitted to the right front wheel FR and the left rear wheel RL.
At this time, the third and fourth inlet valves 221c and 221d, the first to fourth outlet valves 222a, 222b, 222c and 222d, and the first dump valve 231 are kept closed. Then, the first and second balance valves 241 and 242 are switched to the closed state, so that the hydraulic pressure of the first hydraulic circuit 201 is not transmitted to the second hydraulic circuit 202. Then, the second dump valve 232 is switched to the open state to fill the reservoir 30 to the second pressure chamber 113 with oil.
Meanwhile, as described above, the refrigerant is transmitted to the wheel cylinder 40 through the opening and closing operations of the inlet valve 221, the first and second dump valves 231 and 232, and the first and second balance valves 241 and 242 An embodiment of the present invention is characterized in that an inlet valve 221, an outlet valve 222, first and second dump valves 231 and 232, It should be understood that it includes various control modules capable of increasing or decreasing the hydraulic pressure delivered to each of the wheels RL, RR, FL, FR by independently opening and closing the two balance valves 241, 242.
That is, the electromagnetic brake system 1 according to the embodiment of the present invention controls the operation of the motor 120 and the respective valves 54, 221, 222, 231, 232, 241, 242, 261, 262 independently The hydraulic pressure can be selectively transmitted to or discharged from the wheel cylinders 40 of the wheels RL, RR, FL and FR according to the required pressure, thereby enabling precise pressure control.
Next, the case where the above-described electronic brake system 1 does not operate normally will be described. 8 is a hydraulic circuit diagram showing a state in which the electromagnetic brake system 1 according to the embodiment of the present invention operates abnormally.
8, when the electromagnetic brake system 1 is not operated normally, the valves 54, 221, 222, 231, 232, 241, 242, 261, and 262 are set in a non- do. When the driver presses the brake pedal 10, the input rod 12 connected to the brake pedal 10 advances. At the same time, the first piston 21a contacting the input rod 12 advances, The second piston 22a also advances by the pressure or movement of the piston 21a. At this time, since there is no gap between the input rod 12 and the first piston 21a, braking can be performed quickly.
The hydraulic pressure discharged from the master cylinder 20 is transmitted to the wheel cylinder 40 via the first and second backup oil channels 251 and 252 connected to the backup brake for realizing the braking force.
At this time, the first and second cut valves 261 and 262 provided in the first and second backup oil passages 251 and 252 and the first hydraulic circuit 201 and the second hydraulic circuit 291, which are provided downstream of the inlet valve 221, The first and second balance valves 241 and 242 for connecting the first and second balance valves 202 and 202 are normally open type solenoid valves and include a simulator valve 54, an inlet valve 221, an outlet valve 222, And the second dump valves 231 and 232 are constituted by the normally closed solenoid valves, the hydraulic pressure is directly transmitted to the four wheel cylinders 40. Therefore, stable braking can be performed and the braking stability can be improved.
9 is a hydraulic circuit diagram showing a state in which the electronic brake system 1 according to the embodiment of the present invention is operated in the dump mode.
The electromagnetic brake system 1 according to the embodiment of the present invention can discharge only the braking pressure provided to the wheel cylinder 40 through the first to fourth outlet valves 222a, 222b, 222c, and 222d.
9, the first to fourth inlet valves 221a, 221b, 221c and 221d and the first to third outlet valves 222a, 222b and 222c are kept closed and the second balance valve When the fourth outlet valve 222d is switched to the open state, the hydraulic pressure discharged from the wheel cylinder 40 provided on the right rear wheel RR is transmitted to the fourth outlet valve 222d And is discharged to the reservoir (30).
Although not shown in the drawing, the fourth outlet valve 222d is opened to discharge the hydraulic pressure of the wheel cylinder 40, and the first to third inlet valves 221a, 221b, and 221c are opened, , The first balance valve 241 may be opened to supply the liquid pressure to the remaining three wheels FR, RL, FL.
In this manner, by independently controlling the valves 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 241 and 242 of the hydraulic control unit 200, , RR, FL, FR), and precise pressure control becomes possible.
Fig. 10 is a hydraulic circuit diagram showing the non-synchronized state of the electromagnetic brake system 2 according to another embodiment of the present invention.
1, the electronic brake system 2 according to an embodiment of the present invention shown in FIG. 10 is similar to the electronic brake system 1 of FIG. 1 except that the outlet valve 222 There is no difference between the two. The remaining components will be replaced by the description in the electronic brake system 1 according to the embodiment of the present invention.
11 is a hydraulic circuit diagram showing a state in which the electronic brake system 2 according to another embodiment of the present invention is operated in the first dump mode.
The electromagnetic brake system 2 according to another embodiment of the present invention includes first to fourth inlet valves 221a, 221b, 221c and 221d, first and second balance valves 241 and 242, It is possible to discharge only the braking pressure provided to the wheel cylinder 40 through the two-dump valves 231 and 232. [
11, the first, third and fourth inlet valves 221a, 221c and 221d and the first dump valve 231 are kept closed and the second inlet valve 221b is opened When the second balance valve 242 is switched to the closed state, the hydraulic pressure in the wheel cylinder 40 provided in the left rear wheel RL is discharged to the first pressure chamber 112. [ This is because the pressure in the first pressure chamber 112 is smaller than the pressure in the wheel cylinder 40. Further, the second dump valve 232 may be switched to the open state to discharge the liquid pressure of the second pressure chamber 113 to the reservoir 30.
The first hydraulic oil pressure sensor PS11 installed in the first hydraulic oil path 211 is connected to the wheel cylinder 40 provided on the left rear wheel RL (hereinafter simply referred to as the wheel cylinder 40) Can be detected. Therefore, the flow rate discharged from the wheel cylinder 40 can be controlled by controlling the hydraulic pressure supply device 100 in accordance with the output of the pressure sensor PS11 with the first hydraulic oil. Specifically, the flow rate and discharge speed of the wheel cylinder 40 can be controlled by controlling the advance distance and the advance speed of the hydraulic piston 114.
The flow rate discharged from the wheel cylinder 40 becomes larger as the difference between the pressure in the wheel cylinder 40 and the pressure in the first pressure chamber 112 increases. For example, as the hydraulic piston 114 advances and the volume of the first pressure chamber 112 increases, a larger flow rate can be discharged from the wheel cylinder 40.
11 shows that the first dump valve 231 is maintained in a closed state, but it is also possible to open the first dump valve 231 in a different manner. In this case, the hydraulic pressure of the wheel cylinder 40 can be discharged to the first pressure chamber 112 as well as to the reservoir 30 through the first dump passage 116.
12 is a hydraulic circuit diagram showing a state in which the electronic brake system 2 according to another embodiment of the present invention is operated in the second dump mode.
12, the first, third and fourth inlet valves 221a, 221c and 221d are kept closed, the second inlet valve 221b is switched to the open state, and the first dump valve When the second balance valve 242 is switched to the closed state, the hydraulic pressure in the wheel cylinder 40 provided on the left rear wheel RL is transmitted to the reservoir (not shown) through the first dump passage 116 30). This is because the pressure in the reservoir 30 is smaller than the pressure in the wheel cylinder 40. Usually, the pressure of the reservoir 30 is set at atmospheric pressure.
On the other hand, since the pressure in the wheel cylinder 40 is considerably higher than the atmospheric pressure, the hydraulic pressure of the wheel cylinder 40 can be quickly discharged to the reservoir 30 when the first dump valve 231 is opened.
Comparing the first dump mode shown in Fig. 11 and the second dump mode shown in Fig. 12, the first dump mode is used to control the hydraulic pressure discharge of the wheel cylinder 40, The second dump mode can be used.
Fig. 13 is a hydraulic circuit diagram showing the non-synchronized state of the electromagnetic brake system 3 according to another embodiment of the present invention.
In comparison with the electronic brake system 1 according to the embodiment of the present invention shown in Fig. 1, the electronic brake system 2 according to the embodiment of the present invention shown in Fig. 13 corresponds to the second and the There is a difference in that there is no outlet valve 222b or 222c. The remaining components will be replaced by the description in the electronic brake system 1 according to the embodiment of the present invention.
14 to 16 are hydraulic circuit diagrams showing a state in which the electronic brake system 3 according to another embodiment of the present invention is operated in the dump mode.
The electromagnetic brake system 3 according to another embodiment of the present invention can discharge only the braking pressure provided to the wheel cylinder 40 through the first and fourth outlet valves 222a and 222d.
Fig. 14 shows a state in which the hydraulic pressure of the wheel cylinder 40 to which the outlet valves 222a and 222d are connected is discharged.
14, the first to fourth inlet valves 221a, 221b, 221c and 221d and the first to third outlet valves 222a, 222b and 222c are kept closed and the second balance valve When the fourth outlet valve 222d is switched to the open state, the hydraulic pressure discharged from the wheel cylinder 40 provided on the right rear wheel RR is transmitted to the fourth outlet valve 222d And is discharged to the reservoir (30).
Although not shown in the drawing, the fourth outlet valve 222d is opened to discharge the hydraulic pressure of the wheel cylinder 40, the first to third inlet valves 221a, 221b and 221c are opened, The first balance valve 241 may be opened to supply the liquid pressure to the remaining three wheels FR, RL, FL.
In this manner, by independently controlling the valves 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 241 and 242 of the hydraulic control unit 200, , RR, FL, FR), and precise pressure control becomes possible.
The electromagnetic brake system 3 according to another embodiment of the present invention includes first to fourth intake valves 221a, 221b, 221c and 221d, first and second balance valves 241 and 242, Only the braking pressure provided to the wheel cylinder 40 through the second dump valves 231 and 232 may be discharged.
15 and 16 show a state in which the hydraulic pressure of the wheel cylinder 40 to which the outlet valve is not connected is discharged.
15, the first, third and fourth inlet valves 221a, 221c and 221d and the first dump valve 231 are kept closed and the second inlet valve 221b is opened When the second balance valve 242 is switched to the closed state, the hydraulic pressure in the wheel cylinder 40 provided on the left rear wheel LR is discharged to the first pressure chamber 112. [ Further, the second dump valve 232 may be switched to the open state to discharge the liquid pressure of the second pressure chamber 113 to the reservoir 30.
16, the first, third and fourth inlet valves 221a, 221c and 221d are kept closed, the second inlet valve 221b is switched to the open state, and the first dump valve When the second balance valve 242 is switched to the closed state, the hydraulic pressure in the wheel cylinder 40 provided on the left rear wheel RL is transmitted to the reservoir (not shown) through the first dump passage 116 30).